摘要:

ANNUAL REPORTSON THEPROGRESS OF CHEMISTRYANNUAL REPORTSON THEPROGRESS OF CHEMISTRYF O R 1911.ISSUED BY THE CHEMICAL SOCIETYQornmiftet o f gublicrrtion :HORACE T. BROWN, LL. D., F.R.S.J. N. COLLIE, Ph.D., F.R.S.A. W. CROSSLEP, D.Sc., Ph,D., F.R.S.BERNARD DYER, D.Sc.M. 0. FORSTER, D.Sc., Ph.D., F.R.S.P. F. FRANKLAND, Ph. D., LL. D., F.R.S.C. E. GROVES, F.R.S.J. T. HEWITT, M.A., D.Sc., Ph.D.,A. MCKENZIE, M.A., D.Sc., Ph.D.G. T. MORGAX, D.Sc.J. 0. PHILIP, D.Sc., Ph.D.Sir WILLIAM RAMSAY, K.C.B., LL.D.,A. SCOTT, M.A., D.Sc., F.R.S.F.R.S.F. R. S.gbitur :J. C. CAIN, D.Sc., Ph.D.Sltb-&?lfor :A. J. GREENAWAY.Bi;antribufars :H. B. BAKER, M.A., D.Sc., F.R.S.F. D. CHATTAWAY, M.A., D.Sc., Ph.D.,A. D. HALL, M.A., F.R.S.W. D.HALLIBURTON, M.D., F.K.S.F. R. S.A. HUTCHINSON, M.A., PhD.G . CECIL JONES, F. I.C.T. M. LOWRY, D.Sc.S. SMILES, D.Sc.F. SODDY, M.A., F.R.P.VOl. VIII.LONDON:GURNEY & JACKSON, 33, PATERNOSTER ROW, E.C.1913RICHARD CLAY & SONS, LIMITED,BRUNSWICK STREET, STAMFORV STREET, S.E., ANDBUNGAY, SUFFOLKCONTENTS.PAGEGENERAL AND PHYSICAL CHEMISTRY. BY ‘r. M. LOWRY, D.SC. 1INORGANIC CHEMISTRY. By H. €3. RAKER, M.A., D.Sc., F.R.S. . 23ORGANIC CHEMISTRY. By F. D. CHATTAWAY, M.A., U.Sc., Ph.D.,F.R.S., and 5. SMILES, D.Sc. . . . . . . . . 49ANALYTICAL CHEMISTRY. By G. CECIL JONES, F.I.C. . . . 163PHYSIOLOGTCAL CHEMISTRY. By W. D. HALLIBURTON, M.D., F.R.S. 182AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY.By A. D. HALL, M.A., F.R.S. .. . . . . . . 214MINERALOGICAL CHEMISTRY. By ARTHUR H~~rcmNsoN, M. A., Ph.D. 238RADIOACTIVITY. By FREDERICK SODDP, M.A., F.R.S. . . . 26TABLE OF ABBREVIATIONS EMPLOYED I N THEREFERENCES.ABBREVL4TE.D TITLE. JOURNAL.A. . . . . . Abstracts in Journal of the Chemical Society.”Amer. Chem. J.. . . American Chemical Journal.Amer. J. Physiol . . American Journal of Physiology.Amer. J. Sci. . . . American Journal of Science.Anal. Fis. Quim. . . Anales de la Sociedad Espaiiola Fisica y Qnimica.Analyst . . . . The Analyst.Annalen . . . . Justus Liebig’s Annalen der Chemie.Ann. Chiin. Phys. . . Annales tfe Chimie et de Physique.Ann. FaZsif. . . . Annales des Falsifications.Ann. of Botany . . . Annals of Botany.Ann. Physlsik . . .Annalen der Physik.Ann. Report . . . Annual Reports of the Chemical Society.Ann. sci. Univ. Jassy . Annales scientifiques de l’Universit6 de JassyArch. expt. Path. Pharm. . Archiv. fur experimentelle Pathologie und Pharmako-. logie.Arch. Nkerland , . . Archives NQelandaises des sciences exactes etnaturelles.Arch. Pharm. , . . Archiv der Pharmazie.Arch. Sci. phys. nat. . .Arkiv Kem. Hin, Geol. .Atti R. Accad. Sci. Torino.Atti X. Accad. Lincei .Ber. . . . . . Berichte der Deutschen chemischen Gesellschaft.Ber. Deut. bot. Ges. . . Berichte der Deutschan botanischen Gesellschaft.Ber. Deut. physikal. Qes. . Berichte der Deutschen physikalischen Gesellschaft.Bio-Chem. J. . . . The Bio-Chemical Journal.Biochem. Zeitsch. , . Biochemische Zeitsrhrift.Boll. chim.farm. . . Bollettino chimico farmaceutico.Bull. Acad. Sci. Craeow . Bulletin international de 1’Acadbie des Sciences deBull. Acd. Sci., St. Pdters- Bulletin de 1‘Academie ImpQriale des Sciences deBUZZ. Soc. chim. . . Bulletin de la Societd chimique de France.Bull. Xoc. franq. Min.Bull. SOC. g h l . BelgiqucCentr. Bakt. Par. . . Centralblatt fur Bakteriologie, Parasitenkunde undCentr. Min. . . . Centralblatt fur Rlineralogie, Geologie und Pdaeonto-Chem. News . . . Chemical News.Chein. Weekblad . . Chemisch Weekblad.Chem. Zeit. . . . Chemiker Zeitung.Chem. Zentr. , . . Chemisches Zentralblatt.Compt. rend. , . . Comptes rendus hebdomadaires des SQances deFold. Ko’zZ6ny . . . Foldtani Kozlony.Gazzetta . . . . Gazzetta chimica italiana.Qummmi-Zeit. .. . Gu:nnii-Zeitung.J. Agric. Sci. . . . Journal of Agricultural Science.The year is not inserted inmferences t o 1911.Archives des Sciences physiques et naturelles.Arkiv for Kemi, Mineralogi och Geologi.Atti della Reale Accademia delle Scienze di Torino.Atti della Reale Accademia dei Lincei.Cracovie.bourg . . . . St. PBtersbourp. . Bulletin de la Soci6td fraqaise de MinQralogie.Bulletin de la Sociktt2 gkologique de Belgique.Infektionskrankheiten.logie.l’tlcaddmie des Sciencesviii TABLE OF ABBREVlATIONS EMPLOYED IN THE REFERENCES.ABBREVIATED TITLE.Jahrb. Min. . . .Jnhrb. Min. Beil-Bd.Jahrb. Badioaktiv. Elektro-n i k . , . . .J. Anzcr. Chcm. SOC. . .J. Biot. Chem. . . .J. Ind. Eng Chcm.. .J. Path. Bctct. . . .J. Phccrm. Chiin. . .J. Physical Chcrn. . .J. Plzysiol. . . .J. pr. Chcm. .J. Rzcss. Php. Chcm. boc. .‘J. Soc. Chem. Ind. . .Landw. JahrB. . . .Mein. Cdl. Sci. Eng., Ry6t6,We in. illanc hestcr Phil. Xoc.Landw. vCTSl6Chs- st&. .Min. Jug. . . . .Monatsh. . . . .Xon. sci. . . . .Osterr. Zeitsch. Berg. Hut-tcnwcscn . . . .PJilgcr’s Archw . . .Phil. Ha:\. . . .Phil. Trcc?~s. . . .Phyrikal. Zeitsch. . .Proc. . . . . .Proc. Camb. Phil. SOC.Proc. K. Akad, Wetensch:Proc. London Phys. Soc. ,Proc. Physaol. SOC. * . .Proc. Izoy. Soc. . . .Proc. Row. SOC. Edin. .Quart. cJ. i%?icro-#cienca .Rec. trav. chim. . . .Amsterdam.Rend. Accnd. Sci. Fis. Mat.Xapoli . . . .Rev. ye’n. Chim pure appl.Sci.Proc. Roy. Dubl. Soc. .Sitzungsber. I<. Akad. Wiss.Trans. . . . .Trans. Bag. Ceramic Soc. .Trans. Faraday SOC. . .Y’rans. Eoy. SOC. Canada .Tsch. Zin. Jfitt. . .Zeitsch. anal. Chcm. . .Zeitsch. angcw. Chnt. .Zeitsch. morg. CJzcm. . .Berlin.JOURNAL.Neuee Jahrbuch fur Mincralogie, Geologie undNeues Jahrbuch fiir Mineralogie, Geologie iindJahrbuch der Radioaktivitat und Elektronik.Journal of the American Chemical Society.Journal of Biological Chemistry, New York.Journal of Industrial and Engineering Chemistry.Journal of Pathology and Bacteriology.Journal de Pharmacie et de Chimie.Journal of Physical Chemistry.Journal of Physiology.Journal fiir praktische Chemie.Journal of the Physical and Chemical Society 01Journal of the Society of Chemical Industry.Landwirtschaftliche Jahrbucher.Die landwirtschaftlichen Versuchs-Stationen.Memoirs of the College of Science and Engineering,Memoirs and Proceedings of the Manchester LiteraryMineralogical Magazine and Journal of the Mineral-Monatshefte fiir Chemie und verwandte Theile andererNoniteur scientifique.Osterreiehischc Zeitschrift fur Berg- und Hiitten-Archiv fiir die gessmmte Physiologie des MenschenPalaeontologie.Palaeontologie.Beilage-Band.Russia.Kyat6 Imperial University.and Philoqophical Society.ogical Society.Wissenschaften.wesmnnd der Thiere.Philosophical Magazine (The London, Edinburgh andPhilosophical Transactions of the Royal Society ofDublin).London.Physikalische Zeitschrift.Proceedings of the Chemical Society.Proceedings of the Cambridge Philosophical Society.Koninklijke Akademie van Wetenschappen te Amster-Proceedings of the London Physical Society.Proceedings of the Physiological Society.Proceedings of the Royal Society.Proceedings of the Royal Society of Edinburgh.Quarterly Journal of Microscopic Science.Rzceuil des travaux chimiques des Pays-Bas et de laRendiconto dell’ Accademia delle Sienze Fisiche eRevue g6nBrale tle Chimie pnre et appliqu6e.Scientific Proceedings of the Royal Dublin Society.Sitzungsberichte der Koniglich Preussischen AkademieTransactions of the Chemical Society.Transactions of the English Ceramic Society.Transactions of the Paraday Society.Transactions of the Royal Society of Canada.Tschermak’s Mineralogische Mitteilungen.Zeitschrift fiir analytische Chemie.Zeitschrift fiir angewandte Chemie.Zeitschrift fiir nnorgaiiische Chemic.dam.Proceedings (English version).Belgique.Matematiche-Napoli.der Wissenschaften zu BerlinTABLE OF ABBREVIATIONS EMPLOYED Ih’ THE REFERENCES. i XABBREVIATED TITLE.Zeitsch. Biol. .Zeitsch. Chent. Ind. Koiloide:Zeitsch. Elektrochem. , .Zeitsch. Krtjst. Man. . . .Zeitsch. Nahr. Genz6ssm .Zeitsch. lifentl. Chew. .Zeitsch. physikal. Chem. .Zeitsch. physiol, Chem. .Zentr. Physiol. . . .JOUHNAL.Zeitschrift fiir Biologie.Zeitschrift fiir Chemie und Iiidustrie der Kolloide.Zeitschrift fiir Elektrochemie.Zeitschrift fiir Krystallographie und Mineralogie.Zeitschrift fur Un tersuchung der Nahrungs- undZeitschrift fur offer] tliche Chemie.Zeitschrift fiir physikalische Chemie, StochiometrieHoppe-Seyler’s Zeitschrift fur physiologische Chemie.Zentralblatt fur Physiologie.Genussmittel.und Verwandtschaftslehre

ISSN:0365-6217    

DOI:10.1039/AR91108FP001

出版商:RSC    

年代:1911

数据来源: RSC

摘要:

INORGANIC CREMISTRY.IN the Annual Report of the work of 1911, some variation hasbeen made in the subjects in which a summary has been attempted.This variation is due t o the special attention which has been givento particular branches of inorganic chemistry during the course ofthe year. Ot.her subjects might have been selected, but in someof them much more experimental work is necessary before a usefulsurvey could be made. One such subject, for instance, the theoryof the lead chamber-process, has been investigated for some yearspast by Raschig; his results have been criticised by Divers, buta t the present time the subject is in so chaotic a state that onlyfurther experiment can decide which, if any, of the substancesstated to be the intermediate products are really effective in thetransformation.No summary of the year’s work can be complete without specialreference to the very important theory put forward by ProfessorT.W. Richards on the compressibility of atoms. The experimentalevidence adduced in favour of the theory is of the strongest kind,and there is little doubt that other workers will co-operate inaccumulating still further proofs of the theory.Atomic T17eights.The chief alterations recommended by the International Com-mittee on Atomic Weights2 up t o October, are that on thestrength of two papers by Richards and Hiinigschmid theatomic weight of calcium. is decreased from 40.09 to 40.07. Theatomic weight of iron likewise is decreased from 55-85 to 55-84.Mercury has been increased from 200.0 to 200-6 on the work ofEasley, a change which one may hope is not premature.Since thsreport of the Committee has been published, an interesting redeter-mination of the KClO, : KCl ratio has appeared.3 The determina-tion of the products of decomposition of potassium chlorate is amatter of great difficulty if the decomposition is effected by heating.:: A. Stiihler and F. Nryer, Zeilsch. anorg. Chem., 1911, 71, 378 ; A., ii, 881.Faraday Lecture, Trans., 1911, 99, 1201. Bid., 186724 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.This salt occludes water to it considerable extent when crystallising,and this water cannot be removed below the temperature at whichthe salt itself is slightly decomposed. The authors of the papersurmount the difficulty by weighing the chlorate and then fusingi t in an apparatus of quartz, the water given off being collectedand weighed.By subtracting the weight of this water from theweight of original chlorate taken, the weight of the dry salt isobtained. The chlorate was decomposed by hydrochloric acid atOo; the chlorine and oxides of chlorine were, as a precaution, col-lected in a vessel containing liquid air, and the residual chloride wasdried and weighed. The liquefied gases which were condensed wereallowed to evaporate, and the slight residue of pottassium salt whichhad passed over in spray was converted into perchlorate andweighed. The ratio, assuming K : C1= 1.102641, gives K = 39.097and Cl=35*458, atomic weights which differ only in the third placeof decimals from the accepted values.The work of Flint 4 on the supposed fractionation of tellurium,in which an atomic weight of 124.32 was obtained, has beenrepeated5 on material lent for the purpose by Marckwald.Theconditions of Flint's experiments were reproduced as far as possible,and after four successive precipitations of the tetrachloride bywater, the atomic weight, determined by conversion of the elementinto the bromide, showed no alteration. This treatment in thehands of Flint gave a drop of a whole unit in the atomic weight.I n further similar treatment of the material, the oxide was observedto have a yellow colour, which Flint also mentions as occurring inhis fractionation. The authors showed that this colour was due tothe presence of trioxide, the formation of which was traced to theuse of hydrochloric acid which had been exposed to light and hencecontained chlorine.By employing tellurium trioxide instead ofthe dioxide in Flint's atomic-weight determination, an apparentatomic weight of 118.32 was obtained. I f , therefore, Flint's dioxidecontained trioxide, the lowering of his atomic weights is explained.Electric Discharge and Chemical Action.The work of Sir J. Dewar and H. 0. Jones6 on carbon mono-snlphjde, which, in a pdymerised state, mas shown t'o be formedby the action of nickel carbonyl on thiocarbonyl chloride, has beencontiriued with very interesting results. The new method 7 employedwas the action of the silent discharge on the vapour of carbonAmv J.Ski., 1910, [iv], 30, 209; A., 1910, ii, 845.A. G . Vernon Harcourt and H. B. Baker, Tmjts., 1911, 99, 1311.Proc. Roy. SOC.. 1910, A, 83, 408, 526; A . , ii, 408.7 Jbid., 1911, A, 85, 5 7 4 ; A., 1912, ii, 46INORGANIC CHEMISTRY. 25disulphide. This substance was purified carefully by four distinctmethods, the same result being obtained whichever method wasused. The sribstance collected in a U-tube, cooled by liquid air,was at first white, but soon became brown, the transformation beingaccompanied by a flash and sometimes by a detonation sufficientlyviolent to shatter the tube. I f the condenser was cooled t o -210°,the deposit was quite white, but even at this low temperature trans-formation took piace in fifteen minutes.No electric disturbancewas found t o accompany the transformation. The gaseous substanceproduced in the silent discharge tube was found to be still gaseousa t - 1 2 0 O . It disappeared when pamed over cocoa-nut charcoal.The brown substance was analysed, and it was found to correspondalmost exactly with the formula (CS),, thus disproving the assertionof Losanitscha that the brown substance which he prepared in asimilar way was a polymeride of carbon disulphide. The mostremarkable of the chemical reactions of the monosulphide is itsaction on concentrated sulphuric acid. This becomes yellow, thenorange-red, and then deposits sulphur, a brisk effervescence of gas,consisting of carbon monoxide, carbon dioxide, and sulphur dioxide,taking place all the time.The properties of the monmulphidecorrespond closely with those of the brown substance obtained bySidot 9 by the action of light on carbon disulphide.The research which has perhaps aroused more interest and causedmore discussion than any other published during the year, is oneon the chemically active modification of nitrogen.10 It is wellknown that after an electric discharge has been passed through avacuum tube containing small quantities of gas, an after-glow isseen, which may last for some minutes. It has often been suspectedthat the residual glow might be due to a recombination of atomst o re-form the moiecirles which had been broken up by the discharge.Strutt brings evidence t o show that in the case of nitrogen the gashas properties which are not possessed by ordinary 'nitrogen.Acurrent of nitrogen a t low pressures was drawn through a bulbthrough which a high-tension discharge was being passed. Theglowing gas was subjected to vaxious treatment in a tube some20 cm. further on. The glow was found to be destroyed whenthe tube was heated, but re-appeared when the gas reached a coolerpart of the tube. Ordinary phosphorus was converted into amor-phous phosphorus, an increase in weight of 15 mg. being found afterthe passage of two and a-half litres of the nitrogen. Iodine givesBcr., 1907, 40, 4656; A . , 1908, ii, 32.Cowpt. rend., 1872, 74, 179 ; A . , 1875, 1236.lo R. J. Strutt, Proc. Roy. SOC., 1911, A, 85, 219 (Bakerian Lectnre) : A . , ii, 482 ;bid., 1911, A, 86, 5626 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.a bright blue glow, sulphur and arsenic give faint blue and greenglows, selenium, antimony, and carbon are without action.Sodiumand mercury give the nitrides, line spectra of the metals beingdeveloped, and line spectra of cadmium, zinc, lead, magnesium, andpotassium are also obtained when the glowing nitrogen is passedover the metals. Hydrogen merely acts as a diluent of the glow,no ammonia being observed ; oxygen destroys it, apparently withoutany oxidation taking place. On mixing the glowing nitrogen withnitric oxide, nitrogen trioxide is produced, which can be condensedas a blue solid in liquid air. By weighing the nitrogen trioxideformed, an estimate of the percentage of nitrogen rendered activewas arrived at; it was 2-46.A similar estimate obtained from theabsorption by phosphorus gave a percentage of 0.48.It is extremely difficult to estimate the value of the discovery,for a discovery it undoubtedly is, and an important one. Whetherit is really a chemical action, as the author believes, resulting inthe splitting up of nitrogen into charged atoms, true chemical ions,much further work will be necessary in order to decide. The dur&tion of the active character a.fter the electrical discharge is stoppedis very small. The visibility of the glow, and presumably its activecharacter, is not affected on passing through an electric field of3000~volts per centirnetre, and hence gaseous ions cannot be respons-ible for its behaviour.It must be remembered that all the chemicalactions described can be brought about by the electric discharge,and it is conceivable that some hitherto unknown electrical influencemight survive the passage through an electric field. The authoris probably right in assuming that the fact that no liquefactiontakes place at the temperature of liquid air proves that no poly-meride of nitrogen has been formed. If liquid hydrogen were usedas a condensing agent, something different from ordinary liquidnitrogen might be obtained. It is possible that some support maybe gained for the author’s atomic nitrogen hypothesis by thebehaviour of the glowing gas on cooling. The brightening of theglo-N as the gas was cooled may be due to the increased number ofatoms undergoing recombination, or, on the other hand, it mayonly be caused by the increased number of glowing particles inunit volume. The effect of heat in destroying the glow would bedifficult t o understand on the a,tomic nitrogen theory, whilst itrecalls very vividly the behaviour of a vacuum tube through whicha discharge is actually passing.If a point of the tube is heated,the luminosity of the discharge is visible only on either side of theheated suriace. This phenomenon has been noticed by the writerwith tubes conbaining oxygen, nitrogen, bromine, iodine, anINORGANIC c! HEMISTRY. 2'7helium.of the very great interest attaching to the experiments.Whateve'r their ultimate explanation, there is no doubt.Catalytic Action.Since the time wheu Berzelius first introduced the term catalysisinto chemical literature, the efforts of chemists have continued,without cecasing, to endeavour to explain the large number ofchemical actions which, because they are not understood, a.re calledcatalytic.One such class of actions which seems aa far off as everas regards an explanation, is the influence of finely divided metals.The action of iron and nickel on the behaviour of hydrogen withvarious substances has been studied by Neogi and Adhicary.11 Theauthors were unable to confirm the statement of Ramsay andYoung,lz that iron was able to bring about some union betweennitrogen and hydrogen, although reduced iron as well as iron wirewere tried, and a t varying temperatures and different degrees ofdryness.Nickel in various forms was found to be equally ineffec-tive. Reduced nickel was, however, able to induce the reduction ofnitric oxide by hydrogen, ammonia being produced in almost quan-titative amount. The reaction began a t 300°, but once started, itwould go on a t as low a temperature as 120O. Hydrogen sulphideand hydrogen phmphide were also produced by the interaction ofhydrogen and reduced nickel with the oxides of the elements. Itis probable that .in the last two cases nickel sulphide and nickelphosphide were produced as intermediate compounds.In order to test the truth of a theory of Sir J. J. Thomson 1s thatthe catalytic effect of water vapour was due to its high specificinductive capacity, Klein 14 has confirmed and extended someprevious experiments on the influence of various liquids on the dryhydrogen sulphide and sulphur dioxide mixture.15 Eight carefullydried organic liquids were found to bring about an immediatedeposition of sulphur, eight produced a gradual change, while tenmore were without effect.The author can find no relation betweenthe specific inductive capacity of the liquids and their activity ascatalysts, and he believes that his experiments support in all casesan intermediate compound theory of catalysis.The decomposition of hydrogen peroxide by the agency of chromicacid has been the subject of discussion between Spitalsky 16 andZcitsch. nnorg. Chenz., 1910, 69, 209 ; A., ii, 107.j 2 Tt*am., 1884, 45, 93.l4 J.Physical C'lrem., 1910, 15, 1 ; A., ii, 200.l8 H. B. Baker (Wiide Lecture), Mesa. Mccnchester PhiZ, SOC., 1909, 53, 3.l6 Rcr., 1910, 43, 3187 ; A . , ii, 37.l3 Phil. Mag., 1894, [v], 36, 32128 ANNUAL REPORTS ON THE PROGRESS OF CHEMJSTRP.Riesenfeld.17 The former regarded i t its purely a catalytic actionbrought about by the mixture of chromium tri- and sesqui-oxides.The latter, however, shows that the action is a normal one,proceeding according to the equation :4H,Cr,07+ 7H@2=CrZ(Cr2O7)3 + llH20+ 502.A research of a very interesting character by D. L. Chapman andH. E. Jones 18 deals with the decomposition of ozone. It was statedmany years ago by Shenstonel9 that very dry ozone is much lessstable than the moist gas. Armstrong suggested that the cause ofthe rapid decomposition of the dried ozone was that traces of oxidesof nitrogen were formed from small quantities of nitrogen in theoxygen used.The authors have proved that this supposition iscorrect. I n the dried state the oxides of nitrogen act as catalystsin decomposing the ozone, whilst in presence of moisture theseoxides are removed from the sphere of action by being convertedinto nitric acid, which is deposited on the walls of the vessel. Itwits shown that ozone can be kept for some weeks without muchdecomposition even in presence of phosphoric oxide, but if the sealedtubes containing the phosphoric oxide were heated to looo thecatalytic effect of the drying agent was very considerable. I n theactual experiments, therefore, the end of the tube containing theoxide was made to project from the steam jacket, so that it remainedcool while the rest of the tube was kept a t looo.It would doubtlesshave been better if this part of the tube had been sealed off beforethe experiment was commenced, but in order to do this a constric-tion would have been necessary, which would have very muchincreased the length of time necessary for drying the gas. Theresults of six experiments are given, in which tubes containingmoist ozone were heated under the same conditions as tubes con-taining the gas which had been kept for periods of frQm ten daysto three weeks in contact with the drying agent. No appreciabledifference in the amount of decomposition could be found, and itmust be concluded that this action must be added to the list ofthose in which the presence of moisture is not necessary.The otherchemical actions in this cgtegory, as far as the writer is aware, are(1) the combustion of cyanogen,20 (2) the combustion of carbondisulphide,21 (3) the combustion of marsh gas and ethylene,22 (4) theaction of the halogens on mercury.23 The authors give a, newmethod for the preparation of very pure phosphoric oxide, which17 Ber., 191 1, &, 137 ; A., ii, 107.20 H. B. Dixon, ibid., 1886, 49, 384. * Bone and Wheeler, ihid., 1906, 89. 852.23 W. A. Sheustone, ibid., 1897, 71, 471.Trans., 1911, 99, 1811. Ibid., 1897, 71, 471.21 H. B. Baker, ihid., 1894, 65, 616INORGANIC CHEMISTRY. 29for its simplicity and effectiveness will be much appreciated bythose who have hitherto spent many hours in obtaining 1 or 2 gramsof the distilled oxide from 100 grams of the commercial substance.The Rustifig of Iron.Still more evidence has been brought to bear on this problemduring the past year, but it cannot yet be said that agreement ast o the mechanism of the action has been reached. There is nodoubt that pure iron does not rust in contact with pure oxygenand pure water,z4 and further that as much as one-fifth of theoxygen can be replaced by carbon dioxide without rusting takingplace.25 Commercial iron, however, behaves quite differently, and itis with regard to the rusting of this iron, containing perhaps aslittle as 0.3 per cent.of impurity, that so much discussion hastaken place.The recent paper of Dunstan and Hill26 throws muchnew light on the subject. The authors have sought for an explana-tion of the fact that the presence of many substances in solutionprevents rusting, and they have established an important relationbetween the inhibiting effect of such substances and the power ofsuch substances to render iron passive to diluted nitric acid and tocopper sulphate solution. It was shown that the passive state ofiron could be produced by allowing the metal to remain for com-paratively long periods in solutions of highly oxygenated salts, suchas chromic acid, and the permamganate, chlorate, bromate, iodate,and arsenate of potassium, as well as hydrogen peroxide and nitricacid. Besides these, the hydroxides of sodium, potassium, am-monium, and barium, and the carbonates of sodium and potassiumwere found tjo induce the passive condition of the metal.The ironwm passive to nitric acid (D 1.2) and to copper sulphate, but itshould be noticed that the passivity induced by some of thesesolutions was of comparatively short duration. In all cases,however, it was found that those solutions which prevented rustingalso produced the passive state, and since it wits also proved thatdilute acids, even carbonic acid, destroy the passivity, many previousresults, such as those of Friend 27 and of Moody,28 can be explainedwithout the supposition that carbon dioxide is the primary causeof rusting. It must be pointed out, however, that although thesetwo workers used iron which had been made passive by potassiumhydroxide and chromic acid respectively, it does not follow thatthe iron in their experiments would have rusted if it had not beenso treated; indeed, Dunstan and Hill describe an experiment in‘‘I Latnbert and Thornson, Tram., 1910, 97, 2426.35 Lnmbert ( p i v .c o m m . ) ,27 Pruc., 1910, 26, 179.26 Trans., 1910, 99, 1835.28 Truns., 1906, 89, 72030 ANNUAL REPORTS ON THE PXOGRESS OF CHEilIIS'I'RY.which commercial iron immersed in water in contact with oxygenremained bright for six months, and it was only at the end of thisperiod that rusting began. It might quite reasonably be suggestedthat the cause of rusting in this experiment was not the slowdiffusion of dissolved oxygen, which according to the authorsrequired six months to traverse a 14-inch tube, but that it wasreally due to carbon dioxide produced by the oxidation of theindia-rubber stoppers or the paraffin which covered them.Theauthors propose no theory of rusting, but they argue stronglyagainst the so-called electrolytic theory of Walker, Cederholm,and Bent. This might be called a solution-tension theory, butthere is in it no element of true electrolytic action. Dunstan andHill's experiments support the really electrolytic theory of Ti1den.mThe clearest and most forcible statement of this theory has beengiven by Armstrong.30 For rusting to take place, iron must notbe uniformly pure; one part must be capable of becoming electro-negative to the other, and also the water must be sufficiently impureto be a conductor.I f the iron is pure or the water is pure, norusting can take place. Hence, pure iron in water containingcarbon dioxide would not rust, neither would iron containing ironcarbide in ideally pure water, because in neither cam could anelectric current be started. Armstrong does not deal, however, withthe question of the inhibiting action of alkalis. I f impure iron iskept in AT/ lo-sodium hydroxide solution, it will remain unrustedfor an indefinitle period. Here we have il condition of things whichshould f avour chemical action, namely, the impurities capable ofbecoming electronegative to the pure metal, and the couple in con-tact with a conducting solution. How then is the freedom fromrustto be explained on the electrolytic theory? It may be that theimpurities are destroyed by the alkali, a supposition which is perhapssupported by the observation of Dunstan and Hill that a solutioncontaining less than 0.13 per cent.of sodium carbonate will allowrusting to take place. A more likely hypothesis is suggested by theelectrolytic theory. The surface of commercial iron may be regardedas made up of pure iron and impurities such as the sulphide, phos-phide, or carbide of iron and free carbon. These are electronegativeto pure iron, and would become the cathode when the metal wasplaced in an alkaline solution. A transient electrolysis would takeplace, and either or both of two things might happen. The impuri-ties might be coated with hydrogen or the pure metal might receivea superficial coating of oxide.I n any case, electrolysis would stop,and the metal would become passive. Dunstan and Hill describean interesting experiment in which iron is placed in a dilute sodium'JD Trum., 1908, 93, 1356. Scieiicc I'royress, 1911, 22, 311INORGANIC CHEMlSTHY. 31chloride solution containing a few drops of phenolplithalein. I nabsence of air nothing happened, but when air was admitted patchesof pink colour appeared on the surface of the metal, rusting takingplace on the parts which were not coloured. This is to be explained,not by supposing '' a difference of potential set up on the surfaceof the iron b'y the action of the air," but by assuming that thepolarisation of the cathode is destroyed by oxidation, and thattherefore a continuous current can flow and the chemical actionproceed. One must regard the question as still an open one, butthere can be no question as t o the value of the additionalexperimental evidence which Dunstan and Hill have amassed.I n a recent paper,30a Friend states that if iron is kept for someweeks in a 6AT-solution of sodium or potassium hydroxides, thenwashed and allowed to remain in distilled water for some hours,i t is possible to detect sodium or potassium in the water.Heconsiders that the experiments prove that the metal is porous to thealkaline solution, and that it is the absorbed alkali which inducesthe apparent passivity of the iron when placed in water. It is tobe hoped that the experiments will be repeated, especialJy as onlythe exceedingly delicate flame test was used for the detection ofthe metals.The danger of the adventitious introduction of thesemetals in small quantities is, of course, well known, and Friendstates that in his control experiments none was detecJed. Thewriter, after allowing electrolytic iron to remain for a month insolutions of barium hydroxide and sodium hydroxide (2N and Nrespectively), and using rigid precautions to exclude dust, wasnot able to detect the presence of either metal after an exposureof the washed iron to distilled water for five days.Comb ustion.I n the Presidential Address31 Professor H. B. Dixon gave anaccount of the further series of experiments which he and hiscollaborators have made on the important question of the ignition-point, of an expiosive mixture of gases.When the ignition isbrought about by the adiabatic compresion of the gases by arapidly moving piston, it is found that before the ignition-point,that is, the point a t which rapid self-heating takes place, there isa small amount of chemical combination. By 'stopping the pistonbefore the ignition-point is reached, and repeating the compressionseveral times, there is, for example, about 1 per cent. of carbondioxide formed in a mixture of carbon monoxide and oxygen. Thiscombination is called the pre-flame combustion, and it has, byTravis., 1912, 101, 50. y1 Ibid., 1911, 99, 58932 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the heat produced, an influence in bringing the gases up to theignition-point. I n the actual experiments the piston was forcedinto the glms tube containing the explosive mixture by means of aheavy pendulum allowed to fall from a given height.The pistoncould be artificially stopped when the ignition-point was reached.Photographs of the explosion were taken on a rapidly movingphotographic film. By an ingenious arrangement the duration ofthe pre-flame period could be determined; it was of the order of1/1OOth of a second. With a mixture of carbon monoxide andoxygen the ignition-point was found to be 5 0 4 O , whilst Falk, whoused a similar method, but who allowed his piston to move until itwas stopped by the force of the explosion, found 601O for theignition-point of the same gaseous mixture.It is in the pre-flameperiod of combustion that Dixon believes the influence of watervapour is exerted, and when the ignition-point has been reached,the action will proceed independently of its action. Theseresearches are of the very highest importance, since it must be bythe minute study of the simplest cases of chemical action that,if ever, the nature of chemical attraction will be ascertained.The study of some cases of combustion from an entirely differentpoint of view has been undertaken by Bloch.32 Two years agode Broglie and Brizard33 showed that the products of combustionof hydrogen and of hydrocarbons were strongly ionised, while thecarbon dioxide produced by the burning of carbon monoxide hadno conducting power.It seemed that, therefore, there might besome discrimination possible between the character of the chemicalaction in the one case and the other, which might possibly becorrelated with other differences, and that valuable evidence as tothe nature of chemical change might be obtained by the study ofthe ionisation of the products of the change. The results, however,of Bloch lead only to this generalisation, that the flames only of'hydrogen and of substances containing hydrogen are accompaniedby ionisation; other flames, some of which are hot and someaccompanied by little increase of temperature, give rise to noionisation. Among these are the burning of sulphur in air, sulphurin chlorine, and arsenic in chlorine Other chemical actions whichproceed in the dry way give rise to no ionisation, the combinationof hydrogen and sulphur, the combination of sulphur dioxide andoxygen in the presence of spongy platinum, the decomposition ofarsine, and the action of zinc on dried hydrogen Itoccurred to the writer that it might be possible to connect thefive known chemical actions which proceed in the absence of waterchloride.32 Ann.Ckim. Phys., 1911, [viii], 23, 28.Compt. rend., 1909, 148, 1596 ; A , , 1909, ii, 637INORGANIC CHEMISTRY. 33vapour with the production of gaseous ionisation. The combustionof carbon disulphide, whether taking place i ~ 9 a " cold " flame, orburning vigorously in a quartz tube, or exploding with violence,produced no conductivity which could be measured by an electro-meter.Hence it may be concluded that no connexion can beestablished between the two phenomena. It is suggested by Blochthat it is possible that the ionisation which has been observed inthe combustion of hydrogen-containing substances is connected withthe condensation of the water formed and the ionisation producedby the escape of dissolved gases bubbling from the drops. Theexplanation is a possible one, but it may be that the temperatureof these flames being higher than that of the other flames whichgive no result, there is ionisation produced from the heating of thematerial of the jet.The study of the chemistry of explmions in coal mines which isbeing carried out in a really scientific way at the laboratory estab-lished by the Mining Association has produced some papers ofgreat practical, as well as theoretical, importance.The research ofBurgess and Wheeler34 on the lower limit of inflammation ofmixtures of the paraffin hydrocarbons with air has, of course, avery direct bearing on mine explosions, and it is also valuable fromthe scientific point of view. The experiments were performed in alarge spherical globe, so as to eliminate as far its possible the influ-ence of the walls of the vessel. Electric sparks were used to ignitethe mixtures, the electrodes being arranged in the centre of theglobe. It was found that changes in the length of the spark hadno influence on the proportions of the gases which would justinflame between the limits of 10 mm.and 50 mm. Small changesin the initial temperature and pressure, such as might take placein a, mine, had no measurable influence on the limiting proportionsof gas and air. A simple relation between the calorific value andthe proportion of combustiLle gas necessary to form a lower limitmixture was found to hold for five of the simpler parafEnhydrocarbons.IVat er of Cry stallisation.The study of the hydration of salts by a dynamical method isthe subject of a paper by P a r t i n g t ~ n . ~ ~ His results confirm thoseof Tammann,36 and show that the vapour tension of hydrated saltsas determined by t,he dynamic method is always higher than thatdetermined by a static method. The author discusses three possiblehypotheses for the explanation of this fact: (1) that it is owingto the incorrectness of the assumption that water vapour obeya theAnn. Phys.Chem., 1888, [GI, 33, 329 ; rl., 1888, 403.34 Trans., 1911, 99, 2013. 35 &d., 1910, 99, 466.REP.-VOL. VIII. 34 ANXUAL REPORTS OK THE PROGRESS OF CHEMISTRY.gas laws. This he rules out on the ground that the phenomenonappears in the initial stages of a tensimetric measurement. (2) Thatit is due to the presence of a saturated solution retained on thecrystals or occluded in their .interior. This the author considersunlikely, since he believes that with the small crystals used thewater must, if present at all, have been adherent to the surfaceof the crystals, and not included. I f this were the case thepressures recorded would be higher in the first experiments thanin the later ones, whereas the contrary is the case.The authorprefers the third hypothesis, which demands the supposition ofthe existence of an unstable lower hydrate or amorphous salt whichslowly passes into a stable, crystalline modification. The work,however, of T. W. Richards37 shows that included water exists evenin the smallest crystals, and nothing short of molecular divisionwould be able 60 exclude its presence. The second hypothesis seems,therefore, to completely explain the facts, and the supposition ofunstable modifications is unnecessary.Another paper33 describes work which had for its aim thequestion whether salts with water of crystallisation could beobtained of sufficiently constant water content to allow of their usefor atomic-weight determinations.The work had its origin in thediscussion of a, paper by Marckwald,S9 who had determined theatomic weight of tellurium by determining the loss in weight ofcrystallised telluric acid, H,TeO,, and from these determinationshad concluded that tellurium should oocupy its proper place in theperiodic table. The authors determined, not only the total loss ofweight, but also the water produced when the acid was decomposed.The results showed that in spite of the crystals having been driedfor six months over phosphoric oxide, an excess of water over thacalculated amount was present, which must have been shut up inthe body of the crystal. In. estigations were also made to findout if water could pass through a crystal when one face was exposedto a, dried atmosphere and the other to a considerable pressure ofwater vapour.It was found that anhydrous crystals, or thosewhich contained water in chemical combination, such as telluricacid, were impermeable to water vapour, while true hydratesallowed the vapour to pass through them. Crystals were also shownto be impermeable to air a t a pressure of an atmosphere. Themethod used for obtaining the true amount of water of hydrationin crystals consisted of (1) the total dehydration of the salt, so asto get rid of adherent as well as of occluded water; (2) the:Ip Zcitscli. physiknl. Chew%., 1904, 46, 216.w 14. B. Bakcr and G. H. J. Adlam, Traiis., 1911, 99, 507.3g Be?.., 1907, 40, 4370 ; A., 1908, ii, 33INORGANIC CHEMISTRY.35re-hydration in an atmosphere containing water vapour, and finallydrying over a mixture of the anhydrous and hydrated salt. Aninteresting point is that the hydrated substance which contains asnearly as possible the true amount of water shows no crystallineform under the microscope.Rosenstiehl40 suggests that evidence as to the degree of poly-merisation of water can be obtained by observing the manner inwhich water is driven off from hydrated salts, his idea being thatthe same relation would hold as regards the complexity of thewater molecules in the salts as in the water solution from whichthey were crystdised. The author hoped to obtain evidence con-firming or disproving the present view that ordinary water consistsof a mixture of H,O, (H20)?, and (H,O),. One hundred and seventy-nine salts were examined, and it was found that salts can be dividedinto three classes: (1) those containing 1 or 2 and some containing3 molecules of water.(2) Saltswhich contain 3, 6, 9, 12, 15, 18, and 24 molecules of water. Thesesalts lose their water in multiples of 3H,O. (3) Salts containing4, 5, 7, 8, and 10 molecules of water. These give results which mayivdicate that each salt contains two different kinds of water, somecontaining H,O and (H,O),, and others H20 and (€120),. Thereis ingenuity in the idea, but the possibility of the higher polymeridesremaining undissociated at the temperature of dehydration is highlyproblematical.Metals and Alloys.These lose their water at one step.The earlier researches in this field of work were largely directedtowards the solution of the question as to the mode in which themetals in an alloy were united, whether as a chemical compound,a solid solution, or a eutectic mixture.The field is obviously avery large one, and many chemists regard the investigation of thealloys of any particular pair or triplet of metals with littie favour.There is at present a tendency to limit research in this directionto the study of alloys which have some direct use. Dental alloyswhich contain silver and tin have been investigated by Joyner.**In practice these alloys are used as a mercury amalgam, 2nd aremarkable difference has long been noticed as regards t h e amountOF mercury taken up by the filings of the alloy, according as thefilings are used a t o11ce or kept for some rnontlis.Thc " aged "alloy takes up only about half the mercury which the fresh filingsabsorb. The "ageing" can be brought about by Iicciting to 100°for half an hour, and according to the author it makes no differencewhether the heating takes place in air or in hydrogen. Attempts to40 Bull. SOC. chim., 1511, [iv], 9, 281 ; A., ii, 386.41 Truns., 1911, 99, 19536 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.explain the reason of the change in the alloy all failed, althoughsix hypotheses were examined. The author gives no details of themethod used to prevent oxidation of the filings during the heating,but he seems to be unaware of the very great ease with whichmetals can undergo oxidation when ground in an agate mortar.42It seems just possible that the “ageing” may be due to a super-ficial film of oxide.It is demonstrated that at the ordinarytemperature there is no solid amalgam of tin, silver, and mercury.Alloys of aluminium and magnesium, containing only a smallproportion of the latter, have been shown 43 to acquire hardness byheating and quenching in cold water. I f quenched from 500° incold water, the metal is a t first soft, but the hardness increasesin the course of a few days. It was also found that aluminiumalloyed with a small quantity of manganese is not wetted bymercury.A quantitative separation of lead from tin has been effected bydistillation44 in a quartz tube heated in an electric furnace in amercury-pump vacuum.No trace of tin was carried over, even byheating t o a very high temperature. By a special furnace andusing a cathode-light vacuum, it was found that the tig could bevaporised in it porcelain tube.Continuing his researches on the solubility of hydrogen in metals,Sieverts 45 has determined the solubility of this gas in copper, iron,and nickel for pressures up to one and a-half atmospheres and a ttemperatures between 400° and 1600O. The solubility is indepen-dent of the surface of the metal, so that it is due to true solution,and not to adsorption. A t constant temperature the solubility inthe solid and the fused metals is proportional to the square rootof the pressure. A t constant pressure the solubility increases withthe temperature, and there is a sudden increase in the solubilitywhen the metal melts.The temperature-coefficient is greater withfused than with solid copper. The change frofm a- to P-iron is notrecognisable on the solubility curve, but there is a rapid increasein solubility between 800° and 900°, corresponding with the changefrom /3- to y-iron. A t the respective melting points, as the metalsare cooling down, copper gives up 2 volumes, iron 7 volumes, andnickel 12 volumes of the gas, the solidification being accompaniedby “ spitting.”The occlusion of hydrogen by gold-palladium alloys has beenstudied by Berry.** The method is a delightfully simple one, but4y M. C. Carey Lea, Phil. Mag., 1894, [v], 37, 31.43 Wilm, Metallurgie, 1911, 8, 225 ; A., ii, 493.44 Tiede and Fischer, Bcr., 1911, 44, 1711 ; A , , ii, 731.J5 Zeitsch.physikal. Chem., 1911, 77, 691 ; A , , ii, 895.J8 Trans., 1911, 99, 463INORGANIC CEEMISTRT. 37it seems to be open to two objections. The supersaturation of thehydrogen (stated by Troost and Hautefeuille to be about 30 percent. of the whole for the pure metal) is assumed t o bear a constantrelation to the total hydrogen absorbed by the different alloys, andsecondly, dilute sulphuric acid was used for the electrolyte. Sincepalladium is known to be very sensitive to it trace of hydrogensulphide, and this substance is produced at the cathode in theelectrolysis of even very dilute sulphuric acid, i t is probable thatthe results of Hoitzema,47 as well as those of the author, may beinvalidated on this account.In the experiments of Troost andHautefeuille M potassium hydroxide was used as the electrolyte,and since the hydrogen obtained by this method is almost pure, it,is probable that their results are the more trustworthy.Group I .The study of the hehaviour of hydrogen under pressure withsolutions of metallic salts has bem continued by Ipatieff and Werk-howsky.49 The authors had shown that the replacement of metalby hydrogen in these circumstances was accompanied by the forma-tion of oxides, hydroxides, and basic salts. It has now been provedthat, hydrolysis is an important feature in the reaction. A t 25 atmo-spheres pressure and 90°, a N/lO-solution of copper sulphate givesafter fifteen hours a basic sulphate, CUSO,,~CU(HO)~; on furthertreatment this disappears and cuprous oxide is formed, whilst afterfifty hours metallic copper makes its appearance.I n a later paper 5OIpatieff has studied the behaviour of copper nitrate and hydrogenunder a pressure of 100 atmospheres and at temperatures of looo to1 8 0 O . With 2N-solutions of copper nitrate it was found that thebasic nitrate, C'u(N03),,3Cu(HO~,, was produced, as well as nitrousacid. I f the time was prolonged (one hundred and eighty hours),cupric oxide and copper were formed, and the liquid had an alkalinereaction. With N-solution only traces of the basic nitrate wereproduced, cuprous oxide and copper being the main products; butthe liquid after only twenty-four hours became alkaline.With2N-cupric chloride and hydrogen at 100 atmospheres pressure heatedto 1 5 5 O for twenty hours, cuprous chloride was the only solidproduct, whilst if the N/5-solution were used, copper and cuprouschloride were produced. This action was shown to be reversible.Well-defined crystals of nickel were also obtained when A'/ 5-nickelchloride solution was heated to 230° with hydrogen at 100 atmo-spheres pressure.47 Zeitsch. physikal. C?Lem., 1895, 17, 1 ; A . , 1895, ii, 388.43 Compt. rcnd., 1874, 78, 968 ; A . , 1874, 660.4y Uer., 1911, 44, 1755; A., ii, 716. 50 Ibid., 3452 ; A , , 1912, ii, 5038 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Continuing his work on tlhe salts and double salts of the alkalimetals, Barker61 has prepared a, new periodate of lithium,LiIO,,H,O ; a double rubidium magnesium chromate,and the corresponding salt of caesium, C~~Mg(Cr0,)~,6H,0.Theisolation of the last two salts has rendered it possible to show thatthe isomorphous relationship which exists between the simplechromates and sulphates also holds for the double salts,The lithium periodate unfortunately is not chemically similar t othe periodates of potassium, rubidium, and msium,52 since it crystal-lises with water. This prevented the testing of the rule, establishedby the author, that only those members of an isomorphous groupof salts which have nearly equal molecular volumes are capable offorming zone crystals or parallel growths on one another.It hadbeen hoped that lithium periodate, if it could have been preparedin the tetragonal anhydrous state, would have formed parallelgrowths on scheelite (CaWO,), since its molecular volume wouldpresumably be about equal to that of this mineral. It was found,as was to be expected on the author's theory, that no parallelgrowths are formed on scheelite by the periodates of potassium,rubidium, and czsium, since their molecular volumes are muchgreater.During the last, few years a large amount of evidence has beenaccumulated which tends to show that the chemical activity ofsome substances in solution bears no relation t o the electricalconductivity, and therefore to the ionisation of the'solution. It isa pity that this evidence is ignored to a very great extent by theupholders of the dissociation theory.New experiments have beenmade by Gates53 on the replacement of metals in non-aqueoussolutions. They show that in various organic solvents, such asnitrobenzene, carbon disulphide, carbon tetrachloride, ether, andoleic acid, copper salts of organic acids are soluble, and althoughthe conductivity of these solutions are of the order of 2 x 10-10 mho,copper is depwited by the action of cadmium, lead, zinc, bismuth,magnesium, cobalt, tin, iron, aluminium, silver, antimony, andnickel, the activities of the metals being in the order given. It isnoticeable that the order o'f the metals is quite different from theorder of the metals reacting on copper salts in aqueous solutions.Oleic acid, the cunductivity of which is less than 2 x 10-10 mho,dissolves sodium, calcium, and potassium at the ordinary tempera-ture, and copper, zinc, lead, and cadmium at looo.Rb2Mg (CW2,6H,O ;R,Mgl (CM) 0,],,6H20.51 Trans., 1911, 99, 1326.yy J.I'?~?ysicd Chrm., 1911, 15, 97 ; A., ii, 394.52 Barker, ibid., 1908, 93, 15INORGANIC CHEMISTRY. 39The reaction between hypophosphorous acid and copper sulphatehas been examined by Firth and Myers.54 They confirm the originalstatement by Wurtz that a t 70° the precipitate consists of purecuprous hydride. After a few minutes’ keeping in the liquid theprecipitate was found to contain both copper oxide and copperphosphate. The hydride was found to be unstable in the driedstate; it could not be kept, even in absence of air, for more thana day.Group IZ.The preparation of peroxides of zinc and cadmium has beeneffected 55 by the addition of excess of hydrogen peroxide to solutionsof the hydroxides of the metals in ammonia.They are said tohave the composition 10Zn0,,4Zn0,5H,O ; 8Zn0,,4Zn0,7H20 ;5Cd02,Cd0,3H,0, and 5CdQ2,3Cd0,5H,0. They are probablymixtures. The true peroxide of zinc has probably been obtainedby Kazanecky56 by the action of 30 per cent. hydrogen peroxideon potassium or sodium zincoxide. It is white and crystalline,having the composition ZnO,,H,O, but none of the react.ions givendistinguishes it from the possible alternative substance, Zn0,Hz02.The problem of the luminosity of the sulphides of the alkalineearth metads after exposure to light is a very attractive one, andbut little is known as to the cause of the luminoeity.It has beenlong known that the pure sulphides do not exhibit the phenomenon,and that; the luminosity can be very largely increased by thepresence of traces of other metals. Vanino and Zumbusch57 adda fwrther contribution to our knowledge of the subject in showingthat polysulphides of the metals must be present for the exhibitionof luminosity, but the proportion of the polysulphides needs onlyto be very small. Vaillant58 in an attempt to find out the reasonof the luminosity has determined the electrical conductivity of thesulphide. The powder was compressed between two conductingsurfaces, and the system placed in a circuit with a galvanometerand forty accumulators.The conductivity in the dark being 100,thirty-five minutes’ exposure to a 5 c.p. lamp doubled it, and amaximum conductivity of 328 was reached in two hundred and tenminutes. With a 16 c.p. lamp the maximum conductivity of 697was reached in seventy minutes. On removing the light, the con-ductivity showed a further increase, and then €ell quickly for afew minutes. I n the third stage the conductivity decreased5 4 l’rans., 1911, 99, 1329.55 Teletoff, J. Rms. Plzys. C h e m Soc., 1911, 43, 131 ; A , , ii, 490.5756 Compt. rend., 1911, 152, 151.B i d . , 1910, 42, 1452 ; A., ii, 252.pi.. Cheni., 1911, [ii], 84, 305 ; A., ii, 58540 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.steadily in proportion to the time, and, finally, the decrease wasslow and irregular.One cannot fail to be struck with the simi-larity of these results with the results of similar experiments onthe so-called selenium cells, the activity of which, it must berecalled, was shown by Bidwell to be due, not to selenium itself,but to metallic selenides. It has been suggested that the luminosityof the sulphides after exposure to light is due to increased oxida-tion set up by the illumination. The writer finds, however, thatwith sulphides which have been sealed up in very pure nitrogenand in as good a vacuum as can be obtained with a mercury pump,the power of becoming luminous is retained unimpaired for threeyears, during which time traces of oxygen would probably havebeen absorbed.Group ZZZ.The existence of the various hydrates of boron trioxide whichhave been described has been doubtful for a long time.Experi-ments have now been made bD which prove that metaboric, pyroboric,and orthoboric acids are the only hydrates which have a realexistence, and metaboric and pyroboric acids cannot exist in solution.A new material which will be of great service to chemish hasbeen made by fusing alumina in the electric furnace. The crystal-line oxide is powdered and mixed with some binding substance, andmoulded into crucibles, tubes, etc. It bears sudden changes oftemperahre without cracking, and its melting point is so highthat it can be used for melting platinum. The crucibles haveone special advantage in being porous, and can be used instead ofGooch crucibles without any asbestos pad.Filtration and washingof precipitates is very rapid, and a Bunsen burner can be appliedwithout preliminary heating to dry the precipitate. A determina-tion of barium by precipitation with sulphuric acid, made in thewriter’s laboratory, required only twenty minutes, exclusive of thet h e of cooling in the desiccator and the final weighing of thebarium sulphate. The surface of the crucibles is very slightlyhygroscopic, but it is possible that this disadvant’age may beremoved to a great extent by glazing all but the bottom of thecrucible.Group ZV.The behaviour of the diamond a t high temperatures has beenstudied by Doelter.60 It is found that there is no evidence of theconversion of diamond into graphite when heated in carbon dioxideto 1350°, in hydrogen to 1550°, in nitrogen to 1300°, and in chlorine59 Holt, Mcm.Manchester Phil. Soc., 2911, 55, No. 10; 1 ; A., ii, 720.6o Monntsh., 1911, 32, 275 ; A., ii, 601INORGANIC CHEMISTRY. 41to 1200O. In some cases only, the diamond darkens in colour, butthis is probably due t.0 the presence in the diamond of some occludedimpurities. It may be remembered that different specimens ofdiamond behave very differently when exposed to radium eman*tion, the one exhibited by Sir William Crookes a t the British Association meeting in South Africa having been changed from a purewhite to a splendid green, whilst the colours of other diamondsexposed in the same way have been changed to a muddy-brown.Doelter determined the electrical conductivity of the diamond a thigh temperatures in an atmosphere of nitrogen and hydrogen.The resistance undergoes a remarkable fall from 58,800 ohms at950° to 370 ohms at 1220°, which increases to 930 ohms a t 1260Oand falls again to 590 ohms a t 1290O.The interesting series of photochemical researches by D.L.Chapman and his ceworkers is continued in a paper on the combina-tion of carbon monoxide and chlorine.61 Great pains were takento obtain the gases in a pure condition, but the authors concludethat they were not entirely successful, since there always was a11induction period of a short duration on exposing the mixture tolight. This period was so short, however, that when one considersthe effect of a very minute trace of impurity on the rate of change,the gases must have been of a very high degree of purity. Theeffect of adding small quantities of oxygen, ozone, nitric oxide,and nitrogen chloride was found to be the same on the rate ofreaction of carbon monoxide and chlorine as it is with hydrogenand chlorine.The effect with nit>ric oxide is very striking. Whenonly 0.3 per cent. of this gas was present, the mixture was exposedto a carbon arc lamp, and the rate of union was found to beextremely slow.The effect of raising the temperat,ure led to a surprising and whatmust be considered a very important result, that the rate of com-bination in the mixture whicb wits heated to 350° was scarcelyaffected by exposure to light.It was also found that the additionof the gases which were found to inhibit the photochemical changehad no effect on the rate of combination brought about by heat.These results distinguish in a way which has never been so clearlydemonstrated before, the difference between the effect of heat andlight on chemical change.A paper of considerable interest on the gases adsorbed by thewalls of tubes has been published by Guichard.62 Measuring thegases with a MacLeod gauge, it was found that for 100 sq. cm.surface Jena glass gave off 0-03 C.C. of gas a t 600°, porcelain 1.9 C.C.61 Chapman and Gee, Trans., 1911, 99, 1726.Gmpl. rend., 1911, 152, 876; A . , ii, 39642 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.at 1170°, and silica 1.8 C.C.a t 1040O. In the last case the gasconsisted of carbon monoxide, hydrogen, and carbon dioxide. Theresults prove how necessary is the preliminary heating of vesselsused for very accurate work with highly purified gases.Kassner stated some years ago that lead monoxide undergoesoxidation in dry air when exposed to sunlight. The experimenthais been repeated,G3 and it has been found that if the air is driedby means of phosphoric oxide, no oxidahion takes place, even afterseven years’ exposure.Group V .Lobry de Bruyn 64 obtained a crystalline substance by the actionof sodium on hydrazine hydrate, to which he assigned the formulaN2H,*ONa, ammonia and hydrogen being also produced in thereaction. Scand0ls,~5 however, working under slightly differentconditions, comes to a different conclusion.Hydrazine hydrate wasadded drop by drop to finely granulated sodium suspended inether, and the mixture was heated with a reflux condenser on thewater-bath. A white substance was produced, which exploded ondrying, but which on long contact with ether lost this property.The explosive substance decomposes a t 58O, and burns when heatedon platinum foil with a slight explosion. It reduces Fehling’ssolution and ammoniacal silver nitrate. The substance is regardedby the author as a derivative of azoimide.Hydrazine sulphate is decomposed by liquid ammonia at - 3 3 O ,giving ammonium sulphate and hydrazine,66 and by filtering offthe former and allowing the ammonia to volatilise, the hydrazinemay be obtained.It has been found that sulphur dissolves in hydrazine and inhydrazine hydrate,R7 giving a dark brown solution, which on pouringinto water deposits sulphur.A t the ordinary temperatureanhydrous hydrazine dissolves 60 per cent. of its weight of sulphur.After a short time nitrogen is evolved, and an unstable hydro-sulphide remains in solution. Attemptsl made to isolate a hydro-sulphide by the interaction of hydrogen sulphide and hydrazineresulted in the formation of a crystalline substance, which isprobably N,EI,,R,S. Sulphur trioxide is at once reduced byhydrazine, sulphur sequioxide, S,O,, being formed.Riiy,69 in his long and painstaking researches on the nitrites, has‘j:) Arch,. Yhnmn., 1911, 249, 22 ; A . , ii, 284.6.5 Chem.Zmtr., 1910, ii, 544 ; A , ii, 279.67 F. Ephmirn and H. Piotrowski, Bw., 1911, 4.41, 386 ; A, ii, 275.Bec. t m v . chi?n., 1896, 15, 174 ; A . , 1897, ii, 22.Browne and Velsh, J. Amer. Chem. SOC., 1911, 33, 1728 ; A , , ji, 1084.Trans,, 1911, 99, 1012INORGANIC CHEMISTRY. 43studied the effect of adding various nitrates in small quantity tonitric acid while it is allowed to act on mercury. It has been found,whilst the nitrates of sodium, potassium, and manganese have anaccelerating effect on the action, ferric nitrate had a distinctlyretarding effect. The mechanism of the retarding effect in the lastcase is not quitme clear, but it is undoubtedly connected with theinfluence of ferric nitrate in preventing to a great extent the forma-tion of nitrous acid. The explanation which seems to the writeras most likely is that the ferric nitrate is reduced to ferrous saltby mercury,Ga and that the ferrous salt inhibits the formation ofnitrousA very similar problem has been investigated by Rennie andCoAke71 in continuation of their former work.72 The effect wasmeasured of the addition of small quantities of nitrates of thealkali metals on the rate of solution of copper in nitric acid.Itwas found that the accelerating or retarding effects of the nitratesof potassium, rubidium, and cssium were found to be functionsof the temperature and of the concentration of the acid.The monoxide of phosphorus which was prepared by Besaon 73 bythe interaction of phosphoryl bromide and hydrogen phosphide, onthe existence of which as a separate entity some doubts have beencast, has been prepared by Besson and Fournier74 by passing thesilent discharge through a mixture of hydrogen and phmphorylchloride.The reddish-yellow powder produced has propertiesidentical with those of the oxide previously described.The complex and much disputed question of the relations of thethree phosphoric acids has been investigated by Holt and Myers.75It has been shown that pyrophosphoric acid is an intermediateproduct in the hydration of Inetaphosphoric to ort.hophosphoric acid.The result was only obtained qualitatively, since the authors coulddiscover no process for estimating the pyrophosphoric acid in pres-ence of the other two acids. Determinations of the molecularweight of the acids by the freezing-point method pointed to theformula H,PO, for phosphoric acid.For pyrophosphoric acid asample obtained by the decomposition of lead pyrophosphate byhydrogen sulphide gave also a normal molecular weight, whilstanother variety obtained by the dehydration of orthophosphoricacid was probably a mixture of (H4P207), and (H4P207)5. Three69 Carnegie, Trmrs., 1885, 53. 471.'O Veley, Proc. Boy. Soc.. 1593, 52, 27; A . , 1593, ii, 413.71 Trans., 1911, 99, 1035.72 .?bid., 1908, 93, 1162.73 Compt. rend., 1897, 125, 1032; A, 1893, ii, 216.74 Zbid., 1910, 151, 876; A., ii, 35.75 Tmns., 1911, 99, 38444 ANNUAL REPORTS ON THE PROGlRESS OF CHEMISTRY.specimens of metaphmphoric acid prepared in different ways wereexamined, and were found to be HYO,, (HPO,),, and (HPO,),, theacid prepared from the lead salt being again of simplest formula.Phosphoric acid has been found76 to be a useful solventfor certain substances which are only with great difficultyattacked by other reagents.When heated with this acid a t 230°for three hours, silicon was dissolved, giving a colourless solutionand a gelatinous substance in suspension. Zirconium was dissolvedin a few minutes, ferrosilicon, ferrotitanium, titanium nitride, andboron nitride gave clear liquids, and carborundum was entirelydecomposed in three hours. Addition of water to the solutions wasfound to give no precipitate.Group VZ.Jt has seemed strange that whilst liquid nitrogen and liquidhydrogen can be easily converted into the solid state by evapora-tion a t diminished pressure, this conversion has not hitherto beeneffected with oxygen.Sir James Dewar77 has, however, succeededin obtaining solid oxygen by evaporating the liquid at the very lowpressure obtainable by his cooled charcoal method. The melting-point pressure was found to be as low as 1.11 mm., and even whenthis was attained solidification did not at once take place, so greatis the possibility of supercooling in the liquid oxygen.A new method for the production of ozone by chemical meanshas been discovered by Malaq~in.7~ When 20 grams of ammoniumpersulphate mixed with nitric acid are gently heated in an atmo-sphere of carbon dioxide, Ozone is given off, which, purified bypassing through dilute alkali, gives a mixture containing 3 - 4 percent.of Ozone, the rest of the gas being mainly oxygen.An interesting preparation of concentrated hydrogen peroxideis described by F. Fischer and M. Wolf.79 The silent discharge waspassed through a mixture of hydrogen and oxygen under a pressureof 3 mm., a t which pressure the mixture is not explosive, the tem-perature being maintained at the temperature of liquid air. Theyield of hydrogen peroxide in these circumstances is low, but it canbe largely increased if the ordinary pressure is used. I n this case theexplosive mixture must be largely diluted with hydrogen. When3 per cent. of oxygen and 97 per cent. of hydrogen is used, theyield of hydrogen peroxide was 6.4 at 0*22O, 33 per cent.at -20°,76 M. Wunder arid R. Janneret, Compt Tend., 1911, 152, 1770 ; A , , ii, 719.77 Proe. h y . SOC., 1911, A, 85, 589 ; A . , 1912, ii, 40.78 J. Pltmm. Chim., 1911, [vii], 3, 329i9 Ber., 1911, 44, 2956; A . , ii, 1082.-4., ii, 357INORGANIC CHEMISTRY. 4664 per cent. at -80°, and 87 per cent. a t the temperature of liquidair. I f oxygen was used to dilute the explosive mixture, ozonewas produced, but no hydrogen peroxide.Sodium hypoeulphit e has been obtained in concentrated solutionby the electrolysis of sodiuni hydrogen sulphite, using a high currentdensity. Contrary to the opinion generally held, that the salt isdecomposed electrolytically, Jellinek 8O has shown that the decom-position is a spontaneous one. The preparation of pure hyposul-phite from the commercial product is described in another paper.81To a solution in water, sodium chloride is added, and the hypo-sulphite is precipitated as Na2S20,,2H20.This is unstable, but bycareful dehydration a t 60° the stabler anhydrous salt is formed.It is washed with 50 per cent. alcohol and then with absolutealcohol, and dried in a desiccator at 60°. It can then be kept formonths without decomposition. Preezing-point determinationsconfirm the formula lXa.$$O4.A new method of preparing colloidal solutions of selenium isdescribed by Pochettino.82 Solvents of high boiling points, such asanthracene, phenol, or paraffin, are heated with selenium, andacquire a dark red colour. When solidified, the solution (or suspen-sion) appears red by reflected and blue by transmitted light. Evenwhen heated above the transformation temperature, the red doesnot pass into the grey selenium.The selenium can be transferredfrom the solution in which it was prepared to another solvent, forexample, from anthracene to ca.rbon disulphide, without change.When platinum plates connected with the poles of a Wimshurstmachine are placed in such a solution, the selenium is depositedusually on the pmitive pole; from a, solution in carbon disulphide,however, the selenium is deposited on the negative pole. This isa remarkable deveIopment of the most interesting and at the sametime most puzzling experiments made by Picton and Linder83 manyyears ago.An unstable telluride of carbon is produced84 by passing an arcbetween a tellurium cathode and a graphite anode immersed incarbon disixlphide ; the solvent acquires a brownish-red colour andan intolerable odour.On cooling the solution to - looo, glistening,brown crystals separate, which re-dissolve when the temperature isallowed t o rise. The substance is apparently decomposed whenthe solution is heated in a sealed vacuous tube at 185O, free carbonand free tellurium being produced. These were separated by8o ieitsch. Elektrochenc., 1911, 17, 245 ; A . , ii, 482.8l Zcitsch. anorg. Chcm., 1911, 70, 93 ; A . , ii, 2 i 8 .b2 Alti A. Accad. Lincei, 1911, [v], 20, i, 428 ; A., ii, 597.yJ A. Stock and H. Rlumeuthal, Bcr., 1911, 44, I832 ; A , , ii, 722.Trans., 1897, 71, 56846 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTXY.volatilising the tellurium from the weighed precipitate, and assum-ing that they were the sole products of the decomposition of thedissolved substance, the formula CTe, is indicated for the newcompound.The substance has the same unpleasant physiologicaleffects which so many of the compounds of tellurium possess.N o hexahalide derivatives of uranium have hitherto been known,although such compounds of sulphur and chromium are well definedand stable substances. The hexafluoride of uranium has now beenisolated by treating the pentachloride with fluorine at -4OO. Therrksture of tetrafluoride and hexafluoride which is obtained isseparated by distillation. The hexafluoride is an extremely activesubstance, attacking glass in presence of moisture, and reactingvigorously with water, alcohol, ebher, and benzene.It boils at 56’2O.Group VZI.Some experiments have been done by Kiimmell on the electricalleak between two platinum plates at a difference of potential of200 volts, which, if confirmed, will be of great importance. Whenplaced in moist or dry hydrogen, nitrogen, carbon dioxide, oroxygen, only a small leak was noticed when the system wasexposed to an arc light. I n dry c h l o h e the leak was about thesame. When, however, moist chlorine was used, even in the dark,a larger leak was noticed, and this was further increased onexposure to light. Air to which hydrogen chloride had been addedwas found to give the larger leak. The positively charged platinumcylinder was found to be acted on, but not the plate which wasea,rthed. It should be remembered that, Sir J.J. Thomsm hasshown in a somewhat similar series of experiments that no electricalleak is discoverable when moist hydrogen and chlorine are exposedti, light. Experiments in the writer’s laboratory similar to thoseof Kiimmell led to contradictory results, the difference of potentialused, however, being only 100 volts.Higgins 86 in a paper on the action of chlorine on alkalis advancessome objections to the theory of the action of bleaching powderput forward by Taylor.s7 This theory states that the action ofchlorine on alkalis is a reversible one, and that the action of carbondioxide on solutions of bleaching powder is similar to that of otheracids in decomposing both the hypochlorite and chloride present.Taylor showed that the bleaching powder became more active whenfree alkali was removed or by adding calcium chloride to thesolution, provided that no great quantity of free alkali was present,ys Zeitscl~ E’lelclrochem., 1911, 17, 409 ; A., ii, 796.* Trans., 1911, 99, 858.y7 Ibid., 1910, 97, 2541INORGANIC CHEMISTRY. 47Higgins bases his objection to the latter statement by some experi-ments in which lime-water, and lime-water to which calcium chloridehad been added, were exposed to air in similar beakers. Thecalcium carbonate precipitated was weighed, and from the resultsthe conclusion is drawn that there is an increased attraction of thecalcium chloride solution for the carbon dioxide of the air. It seemsto the writer that no certain conclusion can be drawn from suchexperiments. The liquids should have been stirred constantlyduring the whole period to obtain anything like comparable results,especially as the author states that in the pure lime-water thecalcium carbonate formed mostly at the surface of the solution,tending to shield the lime-water from the further action of the air.A further paper has been published by Taylor88 describing somenew experiment’s which strongly support his iormer conclusions.Iodine tetroxide has been the subject of a research by Kappeler,89who has shown that the vasious oxides described as being formedby the action of nitric acid on iodine are only iodine tetroxide,&04. The same substance is also produced by the action of ozonisedoxygen on iodine, which Fichter and Rohner 90 considered tobe Ie09.A useful method of preparing the anhydrous chlorides of metalshas been found by Chauvenet.91 The oxides are heated to a low redheat in the vapour of carbonyl chloride, and a very good yield isobtained.Group VZZI.Claude g2 has submitted neon containing only 5 small quantity ofhelium to electric discharge between small copper electrodes. Themetal volatilises, and on dissolving the sublimed metal in nitricacid it was found to give off eight times as much gas as the sameweight of the unvolatilised electrode. The gas from the sublimatewas found to contain a large proportion of helium. I n repeatingthe experiment 93 with aq tube in the form of a cross with four copperelectrodes, the discharge was passed between one pair of the coppersurfaces, and then between the second pair. It was found thatthe sublimate from the first contained much helium, whilst thatfrom the second contained almost pure neon. Instead, therefore,of being a transmutation of neon into helium as appeared at firstsight possible, it is only a case of selective absorption of helium inpreference to t,he neon by the metallic copper.yx T?*am., 1911, 99, 1906.>+) Eu., 1911, &, 3496; A., 1912, ii, 39.w Ibid., 1909, 42, 4093 ; A., ii, 991.‘’I Compt. ?-end, 1911, 152, 87 ; A., ii, 109.92 Ibid., 1911, 152, 1377 ; A., ii, 602.Zbid., 1911, 153, 713; A., i i , 108748 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.I n order to find out, if possible, if the position of argon, whichfollows potassium instead of preceding it in the periodic classificct-tion, is due to impurity in the argon, F. Fischer and V. FroboeseD4have accomplished the difficult task of fractionally crystallisingargon. The melting point of solid argon lies between the boilingpoint of freshly liquefied air and that which by keeping has lostmuch of its nitrogen. An apparatus was designed by which thesolidand the liquid could be separated at the low temperatures employed.No difference in density, however, was found for the gas which wasobtained from the different fractions, and hence the anomalousposition of argon, like that of tellurium, still remains unexplained.t)4 BcT., 1911, 44, 92 ; A., ii, 20f.H. B. BAKER

ISSN:0365-6217    

DOI:10.1039/AR9110800023

出版商:RSC    

年代:1911

数据来源: RSC

摘要:

ORGANIC CHEMISTRY.OWING to the enormous number of researches now annually carriedout, and t o the difficulty in regarding them in true perspective,it is both laborious and perplexing to report on the progress madeduring a single year in organic chemistry. Rapid as its develop-ment is, a review of twelve months in its history gives but a verybrief glimpse of the highway of progress, and unless some notablediscoveries stand out as guiding marks, it is not easy even to detectthe direction taken. Looking back to ascertain whether organicchemistry is moving in alignment with its past or taking a newdirection, i t seems that recent development might perhaps have beenpredicted after considering the reports of the last few years.In these, attention has been several times drawn to the gradualgrowth among chemists of a conviction that the usual spacial andstructural formulz are in many respects deficient, and of a tendencyto seek the aid of dynamic hypotheses and the conception of residualaffinity.In the yea<r now under review this tendency has becomemore marked, and the most interesting recent applications of theconception of residual affinity are those put forward by Emil Fischerand Alfred Werner in discussing the Walden inversion.Hitherto the theories of residual affinity have been applied intwo chief ways, either in justifying the assumption that certainindispensable additive products are formed during a reaction, orin explaining abnormal phenomena as due to the mutual influenceof unsaturated atoms in the molecular complex.The explanationsoffered of the mechanism of the Walden inversion afford an illus-tration of the former method, whilst Thiele’s theory may be quotedas an example of the latter.Many of those chemists who entertain the view that unsaturatedatoms occurring in the same molecuiar structure may influence theactivity of one another, have drawn some support for their conten-tion from anomalies in certain optical properties of substances.This subject has received attention during the pmt year, the chiefworkers having as their object the correlation of various physicalproperties and the study of the influence of various types ofREP.-VOL. VJII. 50 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.unsaturation. Perhaps one of the more interesting deductions fromthis line of research is the suggestion that the mutual interference ofunsaturated atoms is not confined to cases where these are actuallyunited, but may be found in substances which contain such atomssituated close to one another in space.The number of elements that can act as the central atoms ofmolecules in which there is found no plane of symmetry has beenextended during the year by the synthesis cif optically activecompounds of phosphorus, cobalt, and chromium.The possibilityof the existence of these active cobalt and chromium compounds hadbeen predicted by Werner’s theory of the octahedral structureof compounds containing complexes of the form [MeAs], and theirisolation is valuable evidence of the fundamental correctness of theassumptions underlying his theory of molecular compounds. Thistheory has been repeatedly shown to be capable of withstandingthe severest test to which a theory can be subjected, since itcontinually leads to predictions which subsequent experimentsrealise in the most striking manner.Turning from theory to the more immediate results of experi-ment, it is seen that very considerable progress has been made inelucidating the constitution of substsnces occurring in nature.Among the researches attacking these problems from the analyticalpoiut of view, a prominent place must be given to those dealingwith chlorophyll and hzematin.The synthetical method continuesto be used with great su(xess in work on terpenes and alkaloids.The growing importance of organic arsenic compounds in thetreatment of diseases of protozoal origin is shown by the energywith which their synthesis is being prosecuted, and by the carefulprotection by patent of every new method and compound. For thisreason, as well as on account of their intrinsic interest, they havebeen dealt.with in some detail.Some Physical Properties.The greater portion of the work to be reported under this headinghas dealt with optical propert.ies, such as refractive and rotatorypowers and absorption spectra, and of these perhaps the first-namedhas occupied most attention. Those engaged in work on the refrac-tivities of organic substances will welcome the careful revision 1 ofthe atomic constants which appeared a t the beginning of the year ;the values, being based on more accurate data, replace thoseformerly calculated by Conrady.The chief feeture of the work with this property is the confirma-P.Eisenlolir, Zeitsch. phy,,iknl. Chem., 1910, 75, 585 ; A . , ii, 81ORQANIC CHEMISTRY. 51tion and expansion of the rule laid down by Bruhl : that the occur-rence of unsaturated carbon atoms adjacent to one another causesan anomaly in the refractive and dispersive power of the substance ;thus a study of the dioximes2 has demonstrated that only thosewhich contain the oximinegroups in adjaicent positions areanomalous, whilst others in which these groups are separatedconform to the additive rule. Bruhl's law has been furtherextended, in a direction indicated by its discoverer, to substanceswhich contain other adjacent elements of unsaturated nature, orthoae which are capable of existing in higher states of valency.sExamples of such elements are the halogens, phosphorus, sulphur,and nitrogen.As might be anticipated, the magnitude of theanomaly varies according to the nature of the other elements towhich those in the conjugated system are attached; for example,the acid chlorides (I) exhibit a distinct exaltation, whilst chloro-derivatives of unsaturated hydrocarbons (11) are almost normal :I n some cases a depression may be set up, and it is shown thatthis state is not, as previously suspected, confined t o heterocycliccompounds, but may be exhibited by widely different classes ofsubstances.With the aid of the new atomic constants an exhaustive recalcu-lation4 has been made of the numerical data on which the causalrelation between conjugation and anomaly is based.The chiefobject of this revision seems to have been to trace the effect ofsubstitution in the conjugated system on the magnitude of theexaltation. From the results it is quite clear that substitutiontends to reduce the anomaly; but it seems doubtful whether theaverage values ascribed to various types of conjugated groups canbe accepted as accurate. The influence of substitution may beillustrated by the unsaturated ketones :Type. E.CH:CH%H: CH*CR:O 3.3*CH :CR-CH:CH*CR:O 2.7*CH: CR* CH :CR*CR : 0 2.1Further, it is demonstrated that the position of the substituentsas well as their nature influences the magnitude of the anomaly;F.H. Getmau, Airier. Chew. J., 1911, 46, 539 ; A., ii, 677.K. Auwers and F. Eisenlohr, J. pr. C'hewz., 1911, [ii], 84, 1, 37 ; A . , ii, 781.3 P. Eisenlohr, Ber., 1911, 44, 3188 ; A,, 1912, ii, 2.E 52 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.thus in the three types of grouping, where R is a hydrocarbongroup :c: c*c:c* *CK:C*C:C *C:CR*C:C-(1.1 11. ) (111.)the first shows the greatest and the last the smallest exaltation;but if substituents containing oxygen are inserted in place of R,the exaltation is much increased.5 Complex arrangements of con-jugated unsaturated groups, such as those usually termed '' crossedconjugations," for example :uniformly lead to enhanced exaltation.Other work which is probably of more general interest to thechemist has been undertaken 6 in the study of the relations betweenoptical anomaly and chemical reactivity.By comparing derivativesof ethylenediamine with similar derivatives of piperazine, forexample :it is found that on forming the cyclic system the reactivity of thenitrogen atoms is increased, and this increase in chemical activityis accompanied by an exaltation of refractive power, the open-chaincompound being optically normal. It is thus clear that theformerly accepted rule that ring format'ion is without effect onrefractive power does not always hold, and it is suggested that thiscondition is here due to the conjugation of the unsaturated nitrogenatoms by virtue of their proxiirrity in space.It is interesting tonotice that the evidence for this type of conjugation, or :' space con-jugation" as it is termed, has obtained support7 from anotherphysical property.From this very brief account of recent research in the subjectit is evident that the additive laws laid down by the pioneers ofthe work are becoming narrowed in their scope, and are beingreplaced by other more numerous sets of additive relations. Nodoubt a t some future date the latter will, in their turn, besuperseded.Other investigations have dealt with the influence of unsaturatedgroups on the general absorptive power of substances. This worksK. Auwers, Rer., 1911, M, 3514 ; A . , 1912, 3 , 3. See, however, MissI. Smedley, Truns., 1910, 97, 1475, 1484.H.T. Clarke, Tram., 1911, 99, 1432.7 T. P. Hilditcli, ibid., 1909, 95, 1578.8 C. R. Crymb!e, A. W. Stewart, R. Wright, mil W. G. Glentlinning, ihid., 1911,99, 451ORGANIC CHEMISTRY. 53llas shown that ethylenic compounds exert greater general absorp-tion than the corresponding saturated derivatives ; but if conjuga-tion of the unsaturated groups occurs, there is a marked increasein absorption. I n other respects, however, the relations. of thisproperty to unsaturation differ from those found with refractivepower, for systems containing the crossed conjugation exhibit adiminished absorptive effect. With simple compounds containingiodine it has been observed that a characteristic absorption band isdeveloped when two or more atoms of that element are broughttogether, as in methylene iodide and iodoforrng; and this effect isevidently due to some influence analogous to conjugation.Itappears also probable that a similar relation may hold with com-pounds of sulphur. This element,l* under certain conditions suchas those occurring in the group >C:S, may function as part of achromophore, and in many cases its absorptive effect is greater thanthat of oxygen.Other very interesting researches on the relation betweeu absorp-tive power and the constitution of derivatives of ketopentamethylenehave been madell; but nothing more can be done in this placethan to draw attention to these and to others12 conducted withvapours of simple benzenoid compounds, with hydrazones ofcamphorquinone,l3 and with nitro-derivatives of dimethyltoluidine.14Researches conducted with optically active compounds haveshown that the property is influenced by the presence of unsatur-ated groups and by their relative situation.I n studying aproperty of such highly constitutive nature as this, it is difficulteven approximately to eliminate all disturbing factors, and it isthus impossible to state any general rule 15 as t o the relative influ-ence of the ethylenic and acetylenic systems. Nevertheless, i t hasbeen made clear that the conjugation of unsaturated groups hasa distinct influence16 on optical activity, but, it is interesting tonotice that the magnitude of the anoma,ly depends on the relativesituations of the asymmet.ric and conjugated systems, as well ason other external factors such as the solvent. The generalstudy17 of the influence of the solvent has an important bearing'J C.R. Crytnhle, A. W. Stewait, and R. Wright, Ber., 1910, 43, 1153, 1188,1191 ; A., ii, 470 ; ibid., 1911, 44, 2819 ; A . , ii, 1043.J. E. Pnrvis, H. 0. Jones, and H. S. Tasker, 7'rm%, 1910, 97, 2297.l 1 J. E. Pnrvis, ibid., 1911, 99, 107, 1953.l2 J. E. Purvis, ibid., 811, 1699.l3 F. R. Lankshear and A. Lapworth, ibid., 1785.l5 P. P'. Frankland and H. H. O'Sullivan, ibld., 2325 ; T. P. Hilditcli, ibid., 218.l 8 T. P. Hilditch, zbid., 224.T. S. Patterson and Miss E. F. Stevenson, ibitl., 1910, 97, 2110 : E. C. C. Baly,G. T. Morgan and A. Clayton, ibid., 1941.Zeitsch.ElektTochern., 1911, 17, 211 : A., ii, 45154 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.on this question, whilst other researches with liquids have beenundertaken in order to elucidate 18 the finer influences of constitu-tion on the property. From the data obtained with alcohols con-taining a single asymmetric carbon atom it has been found thatin the homologous series the rotation tends to reach a limitingvalue.Within the two past years magnetic susceptibility has beenaddedlg to the list of physical properties recommended as an aidto the study of constitution in organic substances. The additiveand constitutive features of magnetic susceptibility are fairly evenlybalanced, although the property is undoubtedly more sensitive thanrefractive power to the influence of constitution, and in generalcharacter it may be placed at about a level with magnetic rotation.It has been shown that the molecular magnetic susceptibility maybe represented by the sum of certain atomic values, but the lattervary according to the mode of saturation of the atoms, and afurther allowance in the summation must be made for the generalstructure of the molecule.Nevertheless, if these conditions aretaken into a’ccount, the calculation of molecular value may beperformed with considerable actcuracy.The apphation of the method to determining the constitutionof beuzene does not give decisive results in favour of any of theusual formuh, but if any definite conclusion may be drawn fromthe data, i t seems that the “centric” formula must be chosen.The magnetic susceptibilities of compounds containing the keto-metliylene group have also been measured, and in many instancesthe data point to the presence of the enolic isomeride.It is note-worthy that according to this method freshly prepared acetoaceticester would contain about 70 per cent. and the equilibrium mixtureabout 17 per cent, of the enolic form. As preliminary results, theseare interesting, but since they are a t variance with those givenby chemical inethods20 and by other physical data, it seems thatfurther research is necessary before the property can be appliedwith confidence to problems of this nature.Polgmorphism a?id lsom erism.The terms polymorphism (including, of course, di-, tri-, and tetra-morphism, etc.) and isomerism have been long in use in connexionwith phenomena of an extremely fundamental charactey, and it is18 P.Pascal, Bull. Soc. chim., 1909, [iv], 5, 1110 ; 1910, [iv], 7, 17, 45 ; 1911,[iv], 9, 6, 79, 184, 177, 336, 809, 868 ; L‘umpt. end., 1910, 150, 1167 ; 1911,152,862 ; 24., 1910, ii, 100, 179, 580 ; 1911, ii, 91, 183, 251, 252, 464, 850R. H. Picliard arid J. Kenyon, Tiatace., 1911, 99, 45.20 See laterORGANIC CHEMISTRY. 55therefore of the utmost importance to have a correct understand-ing of the connotation implied. Suppose a substance of a givenchemical composition appears in more than one crystallineform: when this is attributable, not to differences within thechemical molecule, but to a difference in the manner in whichthe molecules as a whole mutually arrange themselves during theact of crystallisation, we are dealing with a polymorphons sub-stance.It is evident that the polymorphous appearance is whollybound up with the crystalline (solid) state; when this condi-tion is lost either by melting, dissolving, or vaporising, all differ-ences disappear. If, on the other hand, the different formsare due to differences within the chemical molecule, they can alsopersist in the liquid, dissolved, or gaseous states, and the formsmust be regarded as isomeric. It’ is seen that polymorphism andisomerism exhaust all the theoretical possibilities. There wouldseem to be an opinion, however, in many quarters that the twoterms merge into one another, and there is a tendency to explaincertain cases as lying on the border line.The non-existence ofsuch a border line has been recently emphasised in an able paperby Biilmann.Z1 Substances are to be regarded as polymorphousprovided that in no1 circumstances are properties exhibited whichare not explicable by a single chemical formula. Great hesitationshould therefore be exercised before designat’ing two forms asisomeric, unless one is finally forced t o that assumption by directobservations resulting from a study either of chemical actions or ofsuch physical properties as have been proved to be of a constitu-tive nature. It may be added that Biilmann’s work on the twomodifications of picrylphenylmethylamine, formerly studied byMantzsch,22 and considered by him to be “ homochromoisomeric ”(see Below), makes it extremely probable that they constitute anordinary case of dimorphism. The same would also seem to applyto many of Hantzsch’s chromoisomeric compounds, but furtherwork is necessary before a final decision can be arrived at.Anotherexample in which two forms have been for long regarded asisomeric, whilst more recent research poixts to dimorphism,is the much discussed case of the cinnamic acids. Stobbe23has made an exceedingly careful study of the mutual transforma-tions of allo- (m. p. 6 W ) and the two iso- (m. p. 4 2 O and 58O) cinna-mic acids. Extreme care was taken to avoid accidental seeding, asis proved by the concordant results obtained. By melting eitherof the three acids, ident,ical fusions are obtained, the identity beinga1 E.Biilinnnn, BL). .. 1911, 44, 827 ; A., i, 307.22 A. Hantzsch, ibid., 1910, 43, 1651 ; A m . A!qwrL, 1910, 78.23 H. Stobbe, Bm., 1911, 44, 2739 ; A., i, 85956 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.proved optically by Stobbe and R ~ u s s , ~ ~ and the introduction of acrystal fragment of any particular modification into the super-cooled fusion always leads to a complete solidification into thatmodification. I n this way, then, any one of the three acids canbe transformed into either of the other two. Transformation ofthe two iso- into the allo-acid may also be effected by inoculationwithout previous melting, the progress of the transformation beingvisible in a melting-point. tube by the growing opacity of the clearcrystals, or under the polarising microscope by the change of inter-ference tint.The 4 2 O acid may be directly transformed into the6S0 acid, or indirectly by changing into the 58" with a subsequenttransformation, but the reverse change caniiot be effected (withoutmelting), so that the 68" acid may be regarded as stable, the 5 8 Ometastable, and the 4 2 O labile. These results are not contrary toexpectation, but t.he further observation that the velocity of trans-formation of the iso-acids into the allo-acid is extraordinarilyincreased by lowering the temperature to - 8 O O or - 1 8 0 O is veryremarkable. It is, however, perhaps not in opposition to theory,for Kruyt 23 shows that the maximum velocity of transformationmay well obtain a t low temperatures, for it will depend, not onlyon the number of crystallisation nuclei, but also on their rateof growth, and these two factors when taken together may yield thehighest result a t low temperatures.A somewhat similar existenceand mutual transformation are met with in the tetramorphouschloroacetjc acid, in which there is no possibility of chemicalisomerism; hence Stobbe draws the conclusion that all three formsof cinna.mic acid are to be regarded as polymorphous forms of theC6H5.!?H Although this workCO,H.C*H.' trimorphous cis-cinnamic acid,does not., perhaps, altogether close the question of the constitutionof the cinnamic acids, it certainly is an indication that the numberof structurally isomeric cinnamic acids is by no means greater thanthe two allowed by geometrical theory.Chromoisomerism and Homochromoisomerism.-These two termshave been proposed and employed for some years by Hantzsch toconnotate the appearance of substances in more than one solidmodification : '' Chromoisomerides are those which are characbr-ised by similar, o r only slightly dissimilar, behaviour in thechemical sense, but which differ from each other in colour, andhence have a different light absorption ; homcxhromoisomerides aredistinguished from the former in that they possess the same colourand identical absorption spectra, molecular extinction, and refrac-11.StobJ3e and F. Reiiss, Bm., 1911, 44, 3735 ; A . , i, 859.25 H. R. Kruyt, ibid., 3108 ; A ., i, 975ORGANIC CHEMISTRY. 57tion.” As examples of homochromoisomerides, Hantzsch citeecertain nitroanilines, stereoisomeric oximes, and coloured salts ofdinitrecompounds.The results of Hantzsch’s former work in this field of research,which related chiefly to the nitrophenols and nitroanilines, weredescribed in last year’s report (p. 78). I n the nitroaniline seriesthe case of 2 : 4-dinitrophenyl-o-tolylamine,is especially noteworthy, as it exists in four different solid m d i -fications, two being orange and two yellow. Now Hantzsch himselfadmits that all the four forms, as indeed is general with all chromo-isomerides, yield optically identical solutions ; they also yield thesame derivatives. Since, then, the difference is restricted to thesolid form, it does not seem necessary to postulate isomerism a t all,but merely polymorphism.It may be remarked that polymorphousmodifications are not invariably of the same colour, and in thosecases where the colour is the same the shade is appreciably different.A close perusal of Hantzsch’s papers certainly gives the impres-sion that the great majority of chromoisomerides are in realitypolymorphous modifications; at any rate, the evidence in favourof polymorphism as opposed to isomerism is overwhelmingly pre-ponderant. Hantzsch avers that polymorphism is out of thequestion, since solutions of certain chromoisomerides in differentmedia are of quite a different colour; and since the solute is alwaysfound to be unimolecular, it can be assumed that the differencein colour of the solution is due to the presence of different chromoisomerides. I n a later pa.per, however, Hantzsch recognises thepossibility, and even regards i t as likely, that the difference incolour is due to the formation of “ solvates,” that is, compounds ofsolvent and solute.As mentioned previously, the chromoisomerism in the nitroanilineseries is only evident in the solid condition, all differences dis-appearing on solution, .and in order t o prove the existence ofisomerism Hantzsch is therefore restricted to a comparison of thephysical properties of certain homologous series ; thus the membersof the homologous series,NO2NO,/-\NR,, \-/where R is methyl, ethyl, or propyl, all dissolve in chloroform,yielding yellow solutions, and the increments in molecularrefraction on replacing methyl by ethyl, and ethyl by propyI ar58 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.respectively 9.5 and 9.4-values which are in close agreement withthe theoretical value 9.2 (Bruhl).On the other hand, in thecorresponding 3 .4-dinitroanilines, the solutions in pyridine of thediniethyl and diethyl compounds are respectively yellow and orange,and the observed increment is only 7.8 instead of 9.2. From thisHantzsch draws the conclusion that the pair of substances cannotbelong to an homologous series, but to two different isomeric series,and hence the difference of colour is due to isomerism. It seemsplausible to suggest, however, that the anomalous result, whichindeed is beyond the range of experimental error, may be due tothe formation in solution of different amounts of the additivecompound of solvent and solute, for pyridine is strongly basic andthe nitroanilines are slightly acidic.During the current year Hantzsch 26 has considerably extendedhis observations, and has prepared a large series of chromoisomericderivatives in the pyridine, quinoline, and acridine series.Ofthese, by far the most numerous and stable forms are afforded bythe phenylacridonium and phenylmethylacridonium salts :CPh CPh/’\Me XPnenylacridonium hydrogen sulphate, for example, exists in threeforms-yellow, red, and green-whilst phenylmethylacridoniumsulphite yields four forms-yellow, red, green, and brown.With allthe new derivatives the solutions obtained from the variouslycoloured modifications are identical ; but the colour of the solutiondepends greatly on the solvent used, as is evident from thefollowing table relating to phenylmethylacridonium sulphite :Ethyl alcohol. Glacial Acetylene di-7- Amy1 acetic and tetra- Aceto- Nitro- Nitro-Absolute. Moist. alcohol. acid. chloride. nitrile. methane. benzene,Red Greenish- Greetiish- Red Green Golden- Yellowish- BrownThe difference of colour in different solvents Hantzsch attributes,not to association or polymerisation, but to the formation insolution of solvates. With respect to the number of chromoiso-merides, Ilantzsch is of the opinion that there are three, namely,yellow, green, and red, all the other coloured varieties beingregarded as due to equilibrium mixtures of these three in differentproportions.Phenylacridonium sulphrtte yields only the three pure26 A. Hantzsch, Ber., 1910, 44, 1783; A . , i, 673.Sellow brown yellow browORGANIC CHEMISTRY. 59isomerides, but phenylmethylacridonium sulphite yields in additionthe dark brown salt, which is to be regarded as a mixture of thegreen and red salts, for on contact with etlier it gives the ether-stable green salt, whereas with chloroform the red salt is obtained.Fo?bmzrlation of Chromoisomerides.-The view formerly held, thatthis isomerism is due to polymerism or association, is now given upby Hant’zsch, in favour of an application of Werner’s theory ofvalency isomerism.As is well known, according to this theory inthe formation of an ammonium salt the acidic and basic partsof the molecule are held together by their auxiliary valencies orresidual affinities :Now in the parent ammonium salts, NH,X, there is no possibilityof isomerism, but with NIE,B/X we have two possibilities:R , i N . . . J:‘X and J2,R‘i.L.. . . KY,and the greater the difference in character between R and R’ themore likely are the t3wo to possess stable individuality. This wouldespecially hold good for the pyridonium arid other bases, becausein them the anion would be united either to H (or CHd or to theunsaturated carbon ring :H,N + E L C ‘ I -+ 11,N.. . . HCI.C,H,N . . . CH,X X*C,H,N*CH, ;(1.1 (1 1.1by addition of methyl iodide to pyridine we should get the twoforms :C,H,N*CH,T! or C,H,iN . .. Ci13T,I-C,H,N*CH, or I*C,HEI,.. . N*CE13.I n the acridine series there is a particularly good agreement betweenthe number of isomerides theoretically possible and those found :R X K\/ R1R-X KThese three formulse correspond with the threeforms-yellow, green, and red.Hantzsch’s work has furnished organic chemistryachromoisomericwith a numberof new compounds, which exist in two or even more differentlycoloured modifications, but his conclusions seem to be more far-reaching than the experimental evidence warrants. It is much tobe regretted that in the examination of the supposed isomeridesHantzsch has not employed any crystallographic methods ; in somecases, it is true, determinations of melting point were made, but i60 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.others the only property employed for discrimination betweensupposedly different modifications was colour, and this is perhapsmore than any other affected by alight impurity.S t e r c o c h e m i s t r y.The Walden Inversion.Some sixteen years ago Walden,27 who was then investigating theoptically active modifications of halogen substituted succinic acids,was led to the wholly unexpected conclusion that in certain reactionsit is possible to convert an active compound containing an asym-metric carbon atom into its enantiomeride, without previouslyracemising it and then resolving the racemic compound.Phenomena of this character, which have been grouped togetherby Emil Fischer 28 under the designation " The Walden Inversion,"although among the most surprising discovered in connexion withoptically active substances, have gp to the present time foundno generally accepted theore tical explanation.The results as yet obtained may be appropriately summarisedhere, as several explanations have been put forward during thepast year to account for them.They all relate to changes in which halogen, hydroxy-, and a.mino-acids are converted the one into the other.As is well known,29 aspartic acid, C0,H*CH(NH,)*C~,*C~2H,can be converted into malic acid, C0,H*CH(OH)*C'H2*C0,H, bynitrous acid, and into chlorosuccinic acid, CO,H*CHCl=CH,*CO,H,by nitrosyl chloride.Again the action of silver oxide convertschlormuccinic acid into malic acid, whilst phosphorus pentachlorideeffects the reverse change.Walden found that if these reactions are carried out withoptically active material, compounds are obtained the signs ofrotation of which are represented in the following scheme:soGI -+ I-chlorosnccinic acid t Pc15 - d-malic acid/- I + I I-Aspartic acid 4gzO AgzO' %o,//P C ~ -+ d-chlorosuccinic acid --+ I-rnalic acid -J.~7 P.Walden, Bar., 1895, 28, 1287 ; ibid., 1896, 29, 133 ; ibid., 1897, 30, 3146 ;ibid., 1899, 32, 1833, 1855 ; P. Walden and 0. Liitz, ibid., 1897, 30, 2795.11:. Fischer, ibid., 1906, 39, 2895.'Ls) Compare Piria, Annulen, 1848, 68, 349 ; Pasteur, Ann. C h i m Ph y3., 1852,[iii], 34, 46 ; Pintti, Rer., 1886, as, 1693 ; Tilden aiid Marshall, Tmnc.., 1895, 67,494OKGANlC CHEMISTRY.61Not only lavorotatory, but also dextrorotatory, chlorosuccinicacid can thus be obtained from one and the same lavorotatoryaspartic acid, according as the amino-group is replaced by chlorineby means of nitrosyl chloride, or is first replaced by hydroxyl bymeans of nitrous acid, the hydroxyl being subsequently replacedby chlorine with the aid of phosphorus pentachloride. Further,lzvorotatory or dextrorotatory chlorosuccinic acid can be convertedeach into its enantiomeride on replacing the chlorine atom by ahydroxyl group through the agency of silver oxide, and thenre-introducing the chlorine in place of the hydroxyl group by meansof phosphorus pentachloride.An optical cycle of changes is thusaccomplished, during which a change of configuration occurs.As simple derivatives of uptically active compounds, in the forma-tion of which no change of configuration is likely to have taken place,frequently show a sign of rotation opposite to that of the parentcompound, it cannot be decided offhand a t which stage of theprocess : action of phosphorus pentachloride or action of silver oxide,change of configuration occurs, and much work has been done inattempts to decide this point.Walden showed that different enantiomerides of malic acid couldbe obtained from the chlorosuccinic acids by simply altering thereagent by which the replacement of hydroxyl was effected, forwhilst either dextro- or lzevo-rotatory chlorosuccinic acid whenacted un by silver oxide yields a malic ac7d of the same sign, it isconverted by potassium hydroxide into a malic acid of the oppositesign, thus: + Ag,O -+ E-irtslic acid+ KOH -+ d-malic acidZ-Chlorosuccinic acid+AgzO -+ d-malic acid+KOH -+ Z-malic acidd-Chlorosuccinic acidOn the ground of prevailing views on the nature of solution,Walden drew the conclusion that in these reactions probably phos-phorus pentachloride and potassium hydroxide act opticallynormally, that is, act without altering the configuration, but thatthe reverse is to be assumed for silver oxide.H e found that although exceptions occur, as a, rule strong basescause a reversal of the rotatory power, whilst feeble bases give amalic acid of similar sign, and suggested that the formation of thedifferent optical isomerides was possibly due to one being producedby direct substitution of hydroxyl for halogen by the interactionof ions, and the other by the intermediate formation of an additivecompound of the base and the acid62 ANNUAL REPOKTS ON THE PROGRESS OF CHEMISTRY.The position reached by Walden can be summarised in thefollowing s,cheme :I-clliorxxjiiccinic acid t P C I ~ I_ d-malic acidNOCl/--+ -------I n all such optical cycles atoms or groups must obviously playa part, which, in the equations ordinarily used to represent thereact;ons, are not showu to be concerned.Similar changes ofconfiguration have been long known to occur during racemisation,but these find a limit in a state of equilibrium characterised byinactivity due to the presence of equal amounts of each activeform.I n the chmges investigated by Walden an acid distinguished byan entirely reversed direction of rotation is obtained.Some years later Emil Fischer30 was led to the subject in thecourse of his work on the amino-acids, and discovered that a similarreversal of rotatory power is effected when the latter are convertedinto the bromo-acids and these are reconverted into the amino-acidsby the action of ammonia.He showed that, as a rule, a cyclicseries of reactions could be carried out, which may be represented,for example, by the scheme:d-Alanine f--- -- d-a-bromopr opionic acid? I.1 I NOBr NOBrI-a-Bromopropionic acid __ NH3 + I-alaoineand noted that the change of configuration might take place eitherduring the action of the nitrosyl bromide or of the ammonia.It is seen from the above scheme that when the halogen of anactive a-bromopropionic acid is replaced by an amino-group,31 analanine of similar rotatory power is obtained.Fischer found thatthis is the case when either the free acid or its ester is employed,but that working in the opposite direction and changing an activealanine into an active a-bromopropionic acid by means of nitrosylbromide, the direction of rotation of the halogen acid produced isE. Fisclier, / ; e ~ . , 1907, 40, 489 ; A., 1907, i, 192.31 It may be noted that in the case of the cl-brorno-fatty acids this replacenlent canbe carried out very easily, whilst Walden was nilable to effect a similar replacementof lialogen by an amiuo-group in the halogen substitute1 succinic acidsORGANIC CHEMISTRY.63different according it8 free alanine or its ethyl ester is employed,in the latter case the product being subsequently hydrolysed, thus:d-Abnine (NH,*CHMe*CO,H) - NOBr -+ I-a-bromoprpionic acid.d-illanine ester(NH2*CHM wC0,Et)NOBr and + 11 yclrol ysisd-a-bromopropionic acid.I n one case or the other, therefore, change of configuration musthave been brought about, and Fischer consequently thought itprobable that optical inversion in the compounds studied by himwas caused by nitrogyl chloride or bromide, that is, its action wassterically abnormal, whilst the replacement of bromine by theaminclgroup through the agency of ammonia was sterically normal,and that therefore d- and I-alauine correspond in configuration withd- and I-a-bromopropionic acid respectively.Similar differences of behaviour between amino-acids and theiresters have been observed in other cases,32 but an exception isfound in a-aminoisovaleric acid, CHMe,*CH(NH,)*C'O,H, or ~ a l i n e , 3 ~as it is called.The a-bromoisovaleric acid obtained by the action of nitrosylbromide on Z-valine gives again the original I-valine when acted onby ammonia, thus:Further investigation, however, has increased the number ofinstances where slight alterations in the groups at,tached t o theasymmetric carbon atom cause reactions t o proceed in opticallydifferent manners.Fischer,34 for example, found that the products obtained fromthe a-halogen fatty acids by the action of silver oxide were opticallydifferent, according as the silver oxide was made to act on thefree halogen fatty acid or the product obtained by coupling its acidchloride with glycine ; thus, whilst I-a-bromopropionic acid yieldsI-lactic acid, &lactic acid is obtained by hydrolysis of the productobtained from I-a-bromopropionylglycine :I-CHMeBr*CO,H - hgaO + d-OH*CHMe*CO,H.Z-CHMeBr*CO.NH*CH,*CO,H j.I-OH-CHMe*CO,H. Ag20 andAgain,35 the action of ammonia on derivatives of the a-halogenfatty acids, although in most cases it yields products of the sameE. Fischer, Ber., 1907, 40, 502 ; A . , 1907, i, 192 ; E. Fischer and 1L Raske,Uer., 1907, 40, 1052; A!., 1907, i, 381 ; 12.Fischer and W. Schoeller, Amalen,1907, 357, 11 ; A . , 1907, i, 1037.33 E. Fischer a d H. Scheibler, Ber., 1908, 41, 880 ; A . , 1905, i, 364.34 Fischer, L'cr., 1907, 40, 494; A . , 1907, i, 192.36 E. Fischer and H. Scheibler, Ber., 1908, 41, 559, 2591 ; A., 1908, i, 324, 85764 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.sign, whether the free acids or their esters or their combinationswith glycine are employed, yet gives optically different a-amineisovaleric acids when d-a-brom&sovaleric acid,CHMe,*CiHBr*CO,H,and d-a-bromoisovalerylglycine, C'HMe,*CHBr*CO*NH*CH,*CO,H,are employed, thus:d-a-Bromoisovaleric acid - NHB + Z-valine.d-a-6romoisova~ery~g~ycine - NH3 and hydrolysis + d-vali ue.The fact that change of configuration does not necessarily accom-pany any particular reaction, but that the reagent effecting itplays an important part, was first established by Wdden when hediscovered that d-malic acid is produced when the halogen Dfd-chlorosuccinic acid is replaced by hydroxyl through the agencyof silver oxide, whilst Lmalic acid results when potassium hydroxidais employed.Other instances have since been discovered, for example,s3Z-a-hydroxy-a-phenylpropionic acid or its ester is converted byphosphorus pentachloride into the corresponding d-chloro-acid, andby thionyl chloride into the corresponding Z-acid, thus :Most cases of the Walden inversion have been observed in trans-formations of a-substituted acids and their derivatives, which aremuch more readily obtained and react more easily than the corre-sponding &derivatives, and it a t first appeared that the inversioncould not be affected where the carboxyl group was not directlyattached to the asymmetric carbon atom; for example, no reversalof the configuration waq shown in the following transformations 37 :Z-OH*CHMe*CH,*CO,H r- -f d-CH1SlleCI*C€I;C02H.PCl5Ag20 or waterHBr or PBr5Ag2O or wateror Na2C03d-NH2*CHPh*CH2*C02H - 11x02 + Z-OH*CHPh*CH,*CO,H,d-NH,*CHPh*CH,*CO,Et - H x O a + t-OH*CHPh~CH,*CO,Et.andZ-OH*CHPh*CH,*CO,H r+ d-CHPhBr-C tl,-C02Hand36 A.McKeiizie and G. W. Clough, Tmns., 1910, 97, 1016, 2566.37 E. Fisclier and H. Scheibler, Ber., 1909, 42, 1219 ; A . , 1909, i, 359 ; A .McKeiizieand 13.B. Y. Humphiies, Trans., 1910, 97, 121 ; E. Fischer, €1. Scheihler,and R. Groh, Ber., 1910, 48. 2020; A., 1910, i, 672ORGANIC CHEMISTRY. 65It has, however, recently been shown38 that each of the activeP-aminobutyric acids39 can be converted into either of the twooptically opposed active P-hydroxybutyric acids, according as theconversion is effected by using nitrous acid, or by first employingnitrosyl chloride and afterwards heating the resulting 8-chloro-butyric acid with water; thus, for example:- H N O ~ + d-N H, C €I &!I em C H2- C: 0, HJ.Z-OH*CPI11Le*CH2.C0,HI NOClI I ~ O -+ cl-OH*CHiHe*CH,*CO,H E-CHMeCl*CH2*C02H -From this i t follows that at least in one of the reactions employeda change of configuration takes place, and the phenomenon istherefore no longer limited to the a-substituted acids.This conclusion has been lately confirmed by the optical inversionof the active P-hydroxy-0-phenylpropionic acids by means ofthionyl chloride, which is found to act differently from hydrochloricacid and phosphorus pentachloride.The interconversion of the hydroxy-acids was realised 40 in accord-ance with the following scheme, which therefore represents the firstoptical cycle actually carried through with the P-hydroxy-acids :d-OH*CHPh*CH,*CO,H - sOCl2 + d-CHPhC1.C H ,*CO,T-f4 I 7'" i10 Z-CHPhCl*CH,*CO,H t SOClz - 2-0 H* CH Ph*CH,* C0,H.During the past year several suggestions have been put forwardregarding the processes which bring about tihe Walden inversion.These are of especial interest, as they involve the abandonment ofthe idea that a carbon atom exerts its affinity by means of fourdirected units, and a reversion to the earlier conception of affinityas a force which acts uniformly outwards from the centre of theassumed spherically shaped atom.Emil Fischer41 regards the Walden inversion as brought aboutby processes which precede substitution, and which depend on anycarbon atom being able t o exert an attractive force on groups notdirectly united with i t nor forming part of the molecule in whichit occurs.38 E.Fischer and H. Scheibler, Sitxungsber. K. Akad. Wiss. Berlin, 1911, 566 ;Annalen, 1911, 383, 337 ; A., i, 527.39 For the purpose of this investigation 8-aminobutyric acid, which had previouslyonly been known in the racemic form, was resolved into its active components bycrystallisation of the d-camphorsulphonate of its methyl ester ; the salt which firstseparates contains the ester of the laevorotatory amino-acid in excess.A.McKenzie and F. Barrow, Trans., 1911, 99, 1910.J1 E Fisclrrr, Annnlen, 1911, 381, 123 ; A . , i, 418.REP.-VOL. V I I I 66 ANNUAL REPORTS ON THE PROGRESS OF CIIEMISTRY.He considers t h a t when an atom or group connected to a carbonatom is replaced, the replacing atom or group need not necessarilyenter in the place of the one which separates, but may just as welltake up another position, which will naturally lead to a differentconfigmation when the substitution takes place on an asymmetriccarbon atom.I n other words, the Waldeii inversion is not t o beregarded as a transformation in the ordinary sense, but as a norma1process which in general can occur as easily as its opposite.Whether the configuration reinains the same during substitutionor is changed, or whether racemisation occurs, is conditioned, onthe oile hand, by the nature of the substituting agent employed, andon the other hand by the nature of the groups attached t o theasymmetric carbon atom.Rejecting the conception of directed valencies, he falls back onthe old idea, revived by Werner, of affinity as a force which actsfrom the centre of the assumed spherical atom to all parts of thesurface. He regards substitution as taking place by the formationof an additive compound, which subsequently breaks down in amanner which may not or may cause a new spatial arrangementof the groups attached to the carbon atom according as the newgroup enters in tlie place previously occupied by the detachedgroup or elsewhere.In the latter case, if substitution takes place on an asymmetriccarbon atom, change of configurztion occurs.Both modes of decom-position may go on simultaneously, when racemisation, which mayeither be partial or complete, occurs. This well agrees with experi-ence, for in all substitution on an asymmetric carbon atom a part oithe product is always racemised, but cases in which racemisxtion occursexclusively or in predominating amount he regards as abnormal.I n order to represent the views thus outlined, he uses a veryingeniously constructed model.A small wooden sphere covered with bristles serves fcr the carbonatom, whilst the attached groups or atoms are represented bycoloured celluloid balls fastened by a wooden peg t o a piece of cork,also provided with bristles.The attached groups can thus conveniently be fixed in any position cn the carbon atom and as easilyremoved, and if the bristle-covered faces fastened to the celluloidballs are so large t h a t they occupy tlie msin part of the sphericalsurface of the carbon atom, an arbitrary change of the spatia!order is prevented.J n using the model one is a t liberty t o assume t h a t sll the foursubstituents may shift themselves a t the same time and in the samesense over the spherical surface, or t h a t the single substituents maymake restricted movements into positions adjacent to the previouspositions of equilibriumORGANIC CHEMISTRY. 67The formation of additive compounds through the secalledresidual affinity or auxiliary valencies may be shown on the modelby the use of the device represented in Fig.2, made out of a wedge-sha.ped piece of cork furnished with brushes, and a wooden pegalso terminated by a brush. The molecule to be added may beaffixed to the carbon atom by the opposite brush surfaces.As an example, Fischer illustrates by the use of this model thetransformation of an active a-bromopropionic acid into a correspond-ing a-aminclacid through the agency of ammonia.For the sake of simplicity he assumes that the additive compoundconsists of one molecule of ammonium a-bromopropionate and onemolecule of ammonia.This is shown in Fig. 1. The balls numberedFig. I. Fig. 1:1, 2, 3, and 4 represent the four groups H, Br, CH,, and CO,NH,attached to the asymmetric carbon atom; the balls numbered5 and 6 represent the NE2 group and the hydrogen atom into whichthe moleculo NH, must divide before substitution takes place.These are to be attached to the carbon atom by its residual valency,as shown in the figure, although Fischer is careful to state thatthis is not an essential condition of his theory, but is assumed forthe sake of simplicity. I f now the halogen (numbered 2) is liber-ated from the carbon atom, either the NH, group (numbered 5) cant,ake its place, the configuration being thus not altered, or one ofk ' 68 BNNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the three other substituents may move into the pmition originallyoccupied by the halogen, and therefore leave its place vacant forthe NH, to pass into.The latter procedure represents the Waldeninversion.I f , finally, both processes occur simultaneously, partial or completeraceniisation follows.Werner 42 has reached very similar conclusions regarding thenature of the process causing the Walden inversion.From a study of many complex inorganic compounds he has beenled to conclude that the central atom of a complex radicle is ableto exert an attraction on groups outside its first sphere of influence,that is, outside the space occupied by the atoms or groups directlyattached to it, the magnitude of the attraction which tends to drawthem into the first sphere depending on the nature of all thegroups.As the attractive force of the central atom on outside groups isconcentrated in a definite direction in space, the position withinthe first sphere which is taken up by any entering group mustcorrespond with this, and consequently be a definite one.The entry of a new group into the first sphere of attraction of asaturated molecule can only occur if some other group passee outof this sphere.Naturally, that group will be expelled which isleast firmly attached, and this will not in any way be determinedby the position which the entering group takes up.Therefore, when an atom or group attached to a central asym-metric carbon atom is replaced by another, the position taken upby the entering substituent is not dependent on the position ofthe group ultimately replaced, but is only dependent on thedirection in which the carbon atom exerts its residual affinity.This is determined by the combined effect of all the groups alreadypresent and by the nature of the attracted molecule, and mayconsequently lead t o change of configuration.Considering, for example, the replacement by halogen of ahydroxyl group attached to an asymmetric carbon atom, we mayD represent the molecule by the formula i>C<oa, or by atetrahedral model, thus :B49 A.Werner, Bey., 1911, a, 873; A . , i, 424ORGANIC CHEMISTRY. 69The four planes through which the attractive force of the centralcarbon atom may make itself felt are the planes ABD, AB(OH),AD(OHj, and BD(0H).I f the attractive force of the central carbon atom happens tobe exerted in the direction of one of the last three faces of thetetrahedron, the resulting new compound will correspond in con-figuration with the compound from which it was derived, inter-change of position within the first sphere of attraction being tacitlyexcluded.If the attraction, however, makes itself felt in the directionof the plane ABD, the optical mirror image of the former compoundwill be produced.Since the residual attractive force of the carbon atom must beexerted in the direction of the same plane in the enantiomeride ofthe original hydroxy-compound on grounds of the general symmetryof the molecule, it follows that if the dextrorotatory halogen deriv-ative is produced from the lzevorotatory hydroxy-compound, thelzvorotatory halogen deriva.tive must be produced from the dextro-rotatory h y dr oxy-comp ound .If the halogen is again replaced by hydroxyl, for example,through the agency of a metallic hydroxide, MeOH, an inter-mediate additive compound, [; C gbJe ]OH, will be formed.Thedirection in which the attractive force of the central carbon atomis exerted on the hydroxyl group can now be different accordingto the nature of the metal which has gone to the halogen atom,because the affinity which the metal has for the halogen is dependenton its nature. Considering now only the cam in which under thisinfluence the attraction of the central carbon atom is exertedoutwards through one of the planes ABX, ADX, or B D X :it is seen that the lzvorotatory hydroxy-compound will be obtainedfrom the laworotatory halogen derivative and the dextrorotatoryhydroxy-compound similarly from the dextrorotatory halogenderivative.I f , however, the attraction is exerted through the plane ABD,each active halogen derivative will yield its hydroxyl enantiomeride.In such a pair of operations there is a possibility of a Waldeninversion being brought about in either of two ways, the chang70 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of configuration occurring at the first or second stage.Inversionmight even occur twice when the configuration of the compoundultimately obtained would be the same as that of the original one.Werner’s view differs from Fischer’s, which was published simul-taneously, only in attempting to give a more explicit presentmentof what may actually take place during replacement.Pfeiffer“3 has more recently stated that in consequence of hiswork on the molecular compounds of the tin series, he had inde-pendently developed ideas regarding the Walden inversion differingbut little from those of Fischer and Werner.He agrees with themin assuming a primary addition of the reagent to the asymmetriccarbon atom, but differs from Fischer in ascribing a substantialinfluence on the end result to the special field of the carbon atomin which addition occurs, and does not follow Werner in assumingthat the primary addition takes place outside the sphere occupiedby the directly attached groups. His views, however, presentnothing new.Either Fischer’s or Werner’s explanation of the process in whichthe Walden inversion is brought about, although inevitablyindefinite owing to our limited knowledge of the nature of affinity,agrees well with known facts.Unfortunately we have little or noexperimental evidence of the actual existence of the additive pro-ducts assumed to be formed. These, however, since they only have atransient existence, must be very unstable, and it may not bepossible actually to isolate them.A further difficulty arises from the circumstance that two opera-tions are necessary to prove the occurrence of a change of con-figuration.It has not hitherto been possible in the case of anypair of reactions to say with certainty in which of the two theactual change of configuration occurs, since very simple operationslike the neutralisation of an acid in which no change of configur&tion can be regarded as probable frequently cause a reversal of thesign of rotation.All the arguments brought forward by Walden, Fischer, andothers to show that the configuration probably alters in one orother of the general reactions employed by them, appear defectivewhen critically examined.It may also be objected that the explanations do not allow thechange of configuration likely to occur in uninvestigated cases tobe predicted. We can, however, only hope to formulate definiterules after our knowledge of these transformations has been verymuch increased.49 P.Pfeiffer, AnnaZen, 1911, 383, 123 ; A., i, 788ORGANIC CHEMISTRY. 71Molecular Asymmetry.W. H. Perkin and W. J. Pope44 have published a paper on the" Optically Active Derivatives of l-MethylcycZohexylidene4-aceticAcid." The paper also contains an account of some opticallyinactive compounds derived from the same acid. The acid itself,having the formulaUH,>C<CH2.CFI 2>c: '<c;*2H9 HH IJH,*CII,was resolved into its optically active components d- and Z- by Perkin,Pope, and Wallach.45 The same authors also found that the inactivedl-acid could be converted into the inactive dl-l-methyl-As-cyclo-hexene-4-acetic acid by the shifting of the double linking from thea& to the By-position. The latter acid wits discovered originallyby Merckwald and Meth.46 Perkin and Pope now find that theactive L1-methylcycEohexylidene-4-acetic acid is also converted intothe inactive dl-acid of Marckwald and Meth.The optically activeacid :is here converted into the inactive &mixture:The addition of hydrogen t o l-methylcyclohexylidene-4-acetic acid,whether dZ-, d-, or E-, gave the same l-methylcyclohexyl-4-acetic acid,of the formula :and the addition of hydrogen bromide gave 4-bromo-l-methylcyclo-hcxyl-4-acetic acid :Both the hydrogenated and the bromo-saturated acids wereoptically inactive. This is in accordance with the theory, the twoformulae only admitting of a, cis- and trans-isomerism respectivelywithout rotatory power.The bromo-acid, when acted on by sodium carbonate solution,gave, by elimination of the bromine and carboxyl groups, theunsaturated hydrocarbon 4-methylene-l-methylcycZohexane,Qt Trans., 1911, 99, 1510.46 Bcr., 1906, 39, 1171, 2404 ; A , , 1906, i, 360, 663.li Ibid., 1909, 95, 178572 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.This hydrocarbon is the same as that obtained by Wallach 47.by theslow distillation, both of the original unsaturated acid, and alsoof &Iarclrwald and Meth's acid. This hydrocarbon is also inactive,its formula not admitting either of optical or of cis- and trans-isomerism.The addition of bromine to the unsaturated acid furnishes com-pounds of especial interest.Here, in addition to a cis- and trans-isomerism, there is also asymmetry of the molecule giving rise tothe possibility of four isomerides. These four isomerides have beenobtained by the authors. Their constitution is represented by thefollowing formulae :Cis-form, d- and I-.CH CH,*CHd>c<CH,*C H:>c<%C13r C0,HThe authors having a t present no method for discriminatingbetween the cis- and tram-forms, propose t o distinguish the twoforms provisionally as a- and P-isomerides. The four isomeridesshowed the following properties :Trans-form, d- and I - .I-P-acid, m. p. 154O, [a]= -24'5O.d-P-acid, m. p. 154O, [a], +24.3O.I'-a-acid,46 m. p. 102O, [a]= +8*6O.d'-a-ac!d,4* ni. p. 102O, [a], not determined.The properties of bhe racemic mixtures were:&&acid, m.p. 145--146O, inactive.d'U-a-acid, m. p. 105-106°, inactive.The I-1-methylcyclohexylidene-4-acetic acid gives the ,?'-a- and theI-P-dibromides, whilst the &unsaturated acid gives the other twoisomerides. The sign of rotation is unchanged for the 8-acids, andreversed for the a-acids.When the dibromide is acted on by sodium carbonate solution,the carboxyl group is eliminated with bromine in the &position,and 1-methyl-4-br~momethylenecycZohexane is obtained :This was obtained in two optically opposite forms, dl- of[ a ] , -50.39O and U- of [a], +50*15O. The a- and P-forms of the47 Anvnlen, 1906, 347, 345; 1909, 365, 267 ; A . , 1906, i, 563; 1909, i, 383.To avoid any possible confusion the suggestion of E.Fischer (Ber., 1907, 40,[i], 102) as to nomenclature has heen adopted ; thus I represents a lzvorotatorycorn pound obtained from a IEVO, whilst I' represents a dextrorotatory compoundobtained from a Izvo. d and d' are used in a similar senseORGANIC CHEMISTRY. 73dibromide gave the same product. The sign of rotation is reversedfrom that of the parent unsaturated acid.By the addition of chlorine t o the compound just described, adichloride was obtained of the formula:sign from thatsuggest that thebeing a mixtureof concentratedthe original acidThis compound was optically active, but had a very slight rotatorypower, the d-form giving [aJD +0*35O, with another reversal ofof the labmentioned compound.The authorslow rotatory power may be due to the preparationof dextro- and hvo-a- and 6-isomerides. The actionpotassium hydroxide solution on the dibromide ofgave a bromeunsaturated acid of the formula :Here, also, the a- and P-isomerides gave the same unsaturated acid,and there is no reversal of sign from that of the original substance :Perkin, Pope, and Wallach 49 claimed that in l-methylcyclo-hexylidene-4-acetic acid there is no asymmetric atom. This viewhas been criticised by E ~ e r e s t , ~ ~ who considers that carbon atmom (1)d-acid, [a]Hgpreen + 12.8’; Z-acid, [a]Hggreen - 12.4O.is asymmetric :because the configuration of the molecule is not the same whentaken either way round the ring relakive to the carbon atom (1).Perkin and Pope reply that their original conclusion stands, andadd : ‘‘ If Everest’s view that a carbon atom is non-asymmetric onlywhen ‘the configuration of the remainder of the molecule is thesame when taken either way, relative to the carbon atom,’ isaccepted, every atom, carbon, oxygen, or hydrogen, in the moleculeof 1-methylcyclohexylidene-4-acetic acid-and, indeed, of anyoptically active substance-is asymmetric.”It does not seem clearly indicated here what the authors wouldhave us to understand by asymmetric hydrogen and oxygen atoms;as regards carbon, however, their contention cannot be sustained,inasmuch as the greater number of the carbon atoms, beingattached by two at least of their affinities to the same groups, forexample, hydrogen atoms, must, e z hypothesi, be symmetrical,whatever may be the nature of the other groups to which.they areattached.Marsh 52 asserts that Everest has replied,51 upholding his view.4g LOC. cit.51 Prm., 1911, 27, 285.Chem. News, 1909, 100, 295; Proc., 1911, 27, 285.52 Ibid., 31774 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the three carbon atoms (I), (4), and (7) are asymmetric, in accord-ance with the definition given by him in 1888.53It may here be recalled that van’t Hoff in 1874 defined an asym-metric carbon atom t o be an atom combined with four differentgroups. Itwas not called asymmetric because it was combined with fourdifferent groups, but (‘ il a 6t6 appel6 asym6trique parceque toutesym6trie fait d6faut dans le groupement qu’il relie.54Every optically active compound must contain an asymmetricatom, although i t did not follow that the presence of asymmetriccarbon in a molecule necessarily entailed optical activity.Van’tHoff, in 1874, had explained isomerism of the maleic and fumarictypes, and in La Chimie duns I’espace (1875) extended his viewsI n 1887 he explained why he called it asymmetric.to ring-linking isomerism and to the type a>C:C:C<d where b e ’he predicted optical activity.In 1888 Baeyer 55 discovered the isomeric hexahydroterephthalicacids, and explained their isomerism on the analogy of maleic andfumaric acids, introducing the terms cis-cis for the maleinoid andcis-trans for the fumaroid forms. €Ie considered the carbon atomsto which the carboxyl groups are attached to be asymmetric, bothwhen linked in the ring and also when doubly linked, and for thiskind of asymmetry where there is no optical activity, and wherethe asymmetry of each atom depends on that of both, he proposedthe term “ relative asymmetry.” I n 1888 Marsh,56 holding theview that a carbon atom situated in a ring could not be regardedin any real sense as combined with four different groups, suggesteda~ a test of asymmetry that, if any two groups attached to one ofthe carbon ato’rns by exchanging positions bring about a change inthe formula as a whole, that carbon atom will be asymmetric.Thisexchange of groups he called the replacement of the carbon atomby its image. The formula obtained by this replacement may bethe mirror image of the original one, or may differ from it in otherrespects without being necessarily itself asymmetric.With regard to the particular instance under consideration here(1-methylcyclohexylidene-4-acetic acid), it is clear that the exchangeof position of methyl and hydrogen attached to C(l) changes thewhole formula into its mirror image.The same change is broughtabout if the ring attachments to C(4) are reversed, and also byexchanging the positions of the CO,H and H attached t o C(7). Onthe other hand, no change is brought about in the formula if thegroups attached to any one of the other carbon atoms change places,53 Phil. McY,~., 1888, [v], 26, 426.54 Dix anndees dam I’histoire d’z69ze the’oric, 1887, p. 25.55 Annaten, 1888, 245, 128 ; A ., 1888, 1069. 56 LOG. citORGANIC CHEMISTRY. 75Optically Active A mino-oxides.Although according to current, views compounds of the typeNa,bcd should exist in two enantiomerides, up to a few years agothe actual isolation of such active compounds had not been realised.Meisenheimer 57 then showed that methylethylaniline oxide, whichis a weak base, could be resolved into two active components byconversion into its d-camphorsulphonate.A t that time it could not be decided whether the free activebases ought to be regarded as true amino-oxides or as the correspond-ing dihydroxy-compounds :as they could only be obtained as viscid, hygroscopic liquids. Thequestion has now been decided in favour of the first alternative,both the dextrorotatory and the lzevorotatory ensntiomeride havingbeen obtained 58 in crystalline form, and their rotations measuredwhen dissolved in anhydrous benzene.I n this solvent the cornpoundscan only be present as oxides, although it is possible that in aqueoussolution they exist in the dihydroxylic forms. Methylethyl$-naphthyla.mine oxide has also been prepared and similarly resolved,as has also kairoline oxide, a, cyclic amino-oxide:c; H,/\//'\QH2I 1\ / V C H 2N/\Me 0It is therefcre probable that all amino-oxides and other com-pounds containing nitrogen, doubly linked to oxygen and alsoattached to three different groups, can exist in two enantiomericforms. Up to the present all attempts to resolve compounds witha double linking between the central nitrogen atom and carbonhave failed, and it seems probable that such compounds can onlyexist in one inactive form.These consequences follow from the assumption that the fournon-ionisable radicles group themselves about the central nitrogenatom in a first sphere of attraction in the relative positions of theangles of a tetrahedron, of which it is the centre, whilst the ionisablemobile group is more loosely attached in a second outer zone insome position opposite the centre of one of the tetrahedral faces.57 J.Meisenheimer, Bcr., 1908, 41, 2966 ; A . , 1909, i, 20.5s J. Meisenheimer, AnnuZen, 1911, 385, 117 ; A . , 1912, i, 2576 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Meisenheimer considers that the different behaviour of compoundscontaining nit'rogen doubly linked to carbon or oxygen may beexplained on the assumption that in the former class the doublelinking takes the place of two non-ionisable radicles of the groupNabcde, whilst in the latter it replaces the ionisable and one of thenon-ionisable groups.It is seen that only in the latter case areer.an tiomerides possible.Optically A ctive Phosphorus Compounds.Two years ago some indications that certain derivatives of phos-phorus should be capable of resolution into optically activeconstituents were observed.59The behaviour of the * 1-menthylamide of phenyl p-tolyl hydrogenphosphate :pointed to its being a mixture.By fractional crystallisation t'his amide was separated into twoisomerides.For the more sparingly soluble or a-isomeride, whichmelted a t llOo, [alD = - 3 2 . 3 O , whilst for the P-isomeride obtainedfrom the mother liquor of the a-form, and probably not quite freefrom it and which melted at 85--8G0, [a], = -37'9O.The Z-menthylamide of phenyl P-naphthyl hydrogen phosphatecan be similarly separatedgO into a sparingly soluble and a moresoluble constituent. The first or a-isomericfe melts at 135-136O,and gives [alD -37.2O; the second or B-isomeride melts at 94-96O,and gives [aID about -29O.Meisenheimer and Lichtenstadt 61 have recently shown thatplienylmethylethylphosphoric oxide :can exist in optically active forms, and have thus first obtained aderivative of phosphorus, the optical activity of which is withoutdoubt due to the asymmetric distribution of the radicles aroundthe phosphorus atom.They were led to attempt the resolution of this compound by thesurprising ease with which the racemic amino-oxides could beseparated into pure optically active components ; this was effected59 R.D. W. Luff and F. S. Kipping, Trans., 1909, 95, 1993.F. S. Kipping and F. Challenger, ibid., 1911, 99, 626,J. Meisenheimer and L. Lichtenstadt, Ber., 1911, 44, 356 ; A., i, 344ORGANIC CHEMISTRY. 77in the case, for example, of kairoline oxide by a single crystallisationof the d-tartrate or d-bromocamphorsulphonate.The phenylmethylethylphosphoric oxide required was prepared bycombining methyl iodide with diphenylethylphosphine, and thenheating the base set free from this by silver oxide with water,when benzene was split off and the oxide obtained:C,%\ C P 5 \ C2H5\ CH UH,-\C H -P --+ C,H5-P<ICH" -+ C H -P<OH3 --f C2H5--P:0.CiH:/ C,HJ C:H:/ C 6 dWhen brought together with the equivalent quantity of d-bromo-camphorsulphonic acid dissolved in ethyl acetate, the base and acidcombine, and after a time a well crystallised salt separates.This melts a t 94--95O, and in aqueous solution gives [a], + 67*4O,these values not changing on recrystallisation.The value [MID + 3 2 3 O for the rotation, obtained from this,indicates the presence of an optically active phosphorus ion,PhMeEtP-OH, with a rotation of +48O.This optical activity can only arise from the asymmetric groupingof the radicles about the phosphorus atom, which, therefore, likethe nitrogen atom, can give rise to optically active compounds whenits five valencies are saturated by different radicles.The phenylmethylethylphosphoric oxide which is obtained as acolourless, crystalline compound by passing dry ammonia into abenzene solution of the d-bromocamphorsulphonate of the activebase is also optically active, having [a],, + 23'1" in water, + 2 5 O inN-hydrochloric acid, and + 3 3 ' 8 O in benzene.This shows that, as with nit'rogen, the saturation of the fivevalencies of a phosphorus atom by only four different radicles issufficient to give an symmetric configuration t o the molecule.Asymmetric Cobalt Compounds.Werner's theory of molecular compounds based on the assump-tion of principal and auxiliary valencies has been frequently appliedby him with great success to group together numerous classes ofcompounds not previously very clearly brought into relation.During the past year a number of deductions from this theoryrelating to the possibility in certain cases of the existence ofenantiomerides have been most strikingly verified, and have givena weighty confirmation of the fundamental correctness of theunderlying assumptions.According to this theory the six groups, so frequently associatedwith a metallic atom in complexes62 of the form [Me A6], are62 Me =metallic atom.A or B = co-ordinated atom or group78 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.arranged in space around this central atom in the relative positionsof the angles of an octahedron (I), which is conventionallyrepresented and numbered as in (11):(1.1 (11.)This representation leads to various conclusions capable of beingput to the test of experiment; for example, when the six co-ordin-ated groups are the same, as in [Me A& or contain a single othergroup as in [Me+], the resulting compounds should exist in one- -form only, whilst.those having the composition Me 4 should exist 1 il in cis- and trans-isomeric series, having configurations which maybe represented thus :A ? B A B A I ___-Me ' I , I --A f i AThis important deduction, as is well known, has been confirmedin the case of compounds of the elements platinum, cobalt, andchromium.-4gain, in certain cases the theory predicts the existence of opticalisomerism; for example, if the groups B, C, and D are situatedrelatively to the central atom in the positions of the angles of oneface of the octahedron, compounds containing complex radicles ofthe form [: Me 31 should give pairs of optically opposedisomerides of the configurations :A ? C C B A/T-7I Me IU j i Awhilst compounds containing complexes of the compositionc", Me if the groups attached to the metallic atom have thORGANIC CHEMISTltY.79following relative positions, should similarly be capable of resolutioninto oppositely active components :B y cIT-/I Me IIn such compounds i t is not indeed necessary for four or eventhree different groups to be present if two pairs are connected, foronly a different spacial orientation of the connecting chain is neededto cause molecular asymmetry.Such a possibility exists, for example, in compounds where thegroups C C and D D axe replaced by ethylenediamine,that is, among compounds containing the complex radicles :(NN,*CI1,*CH2-NH, =en),If the configuration f ormuke of such compounds are constructedfor the cases where the groups A 23 and A A are attached toadjacent angles, that is, are in the cis-position, it is seen that inboth non-superpwable mirror images are possible :(11.1whilst in the cases in which the A and B or A groups are in thetrans-position the mirror images are superposable :AIh(111.80 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Compounds of the types (I) and (11) should therefore be capableof resolution into optically opposed active components, whilstcompounds of the types (111) and (IV) should not be so resolvable.Numerous examples of these types are known among the com-pounds of cobalt, and Werner has recently been able t o resolvemembers of the first two classes into their optical enantiomerides,and to show that members of the last two cannot be so resolved.Among compounds of the first type members of the followingtwo series:l-Chloro-2-amniincdiethylenedia1ninecobaltic salts.and1 -Brorno-2-amminediethylenediamin ecobaltic salts.by the help of the d-bromocarnphorsulphonates have been resolved 83into optically active components, which may be represented by theabove configuration formulz.I n both cases the d-bromocamphor-sulphonate of the d-form is less soluble than that of the 2-form.The procedure adopted was as follows : l-chloro-2-amminediethylene- [[:I 23N Co en, Cl,, dissolved in warm diaminecobaltic chloride,water was mixed with a solution of the silver salt of d-bromo-camphorsulphonic acid of appropriate strength.After separationof the silver chloride, the d-chloroamminediethylenediaminecobalticd-bromocamphorsulphonate first crystallised out, the mother liquorfrom these crysta.1s then solidifying after some hours to a pulp ofcrystals of the corresponding 1Evo-salt. Each could be recrystallisedfrom hot water. The corresponding active bromo-salts were similarlyobtained.63 A. Werner, Ber., 1911, M, 1887 ; A . , i, 613.ORGANIC CHEMISTRY. 81From the d-bromocamphorsulphonates other salts can be preparedwithout difficulty.The bromides, for example, are obtained byadding concentrated hydrobromic acid to the sulphonates. Thelatter dissolve, and after a short time the bromides crystallise out.The rotatory power of the salts of the active components is con-siderable. For the 1 * chlor+2-amminediethylenediaminecobalticbromides, [a], = & 43O ; for the 1-bromo-2-amminediethylenediamine-cobaltic bromides, [a] = & 46.25O.The active compounds are very stable; the aqueous solutions ofthe bromides, for example, [EN Coen2]Br2, can be kept for along time a t the ordinary temperature or even heated just toboiling without undergoing rac2misation.The activiby is also maintained when the non-ionisable halogenatom in the complex radicle is removed with silver nitrate accordingto the equation:showing that the nquoamminediethylenediaminecobaltic salts alsocan exist in optically active forms.A further increase64 in our knowledge of this type of compoundhas resulted from the resolution of l-chloro-2-nitlrodiethylene-c1 diaminecobaltic salts of the general formulaoptically active components, which may be represented : .Co m,]X intoThese differ from the 1-halogen - 2 - amminediethylenediamine-cobaltic salts in the circumstance that they contain two acidresidues within the complex [g:N Co en2], which in consequence isunivalent, whilst in salts of the former class only one acid residueis included within the bivalent complex [gap Coen,].Resolution was effected by taking advantage of the- circumstancethat I-1-chloro-2-nitrodiethylenediaminecobaltic d-camphorsulphon-ate is sparingly soluble, and d-1-chloro-2-nitrodiethylenediamine-cobaltic d-camphorsulphonate is very easily soluble, whilst theG4 A.Werner, Ber., 1911, 44, 3272; A., 1912, i, 10.XEP.-VOL. VIII c82 ANNUAL REPORTS ON THE PROGRESS OF CI-IEMIS'I'RY.reverse is the case with the corresponding d-bromocamphor-sulp honates.The difference in solubility is so great that on mixing a concen-trated solution of racemic 1-chloro-2-nitrodiethylenediaminecobalticchloride with a suitably concentrated solution of ammoniumd-camphorsulphonate or d-bro~mofcamphorsulphonate respectively,the corresponding salt of the lzvoc or dextro-component separatesin a pure condition.The active 1-chloro-2-nitrodiethylenediamine-cobaltic salts show the phenomenon of mutarotation in aqueoussolution, the initial rotation not remaining constant, but rapidlyincreasing; [a], initially = 20°, rapidly increases to 53O, where i tremains constant. This is due to the conversion of the chloronitro-into the nquonitro-salt, the non-ionisable chlorine ato'm showing arelatively great reactivity, and in aqueous solution going withreadiness into ionisable union, thus :The aquonitrcsalts, like the aquoammine saIts, can thereforeexist in optically active forms.The active chloronitro-salts can be converted into other seriesof similar compounds without loss of optical activity, for example,by the action of potassium thiocyanate the a'ctive thiocyanatonitroecompounds are produced, thus :[(l) c1 Co en2 Cl+ 2KNCS = 2KC1+ [F:: Co en, INCS.(2) O2N 1Among compounds of the second type members of the followingtwo series have been resolved into active compounds, the configura-tion of which is shown:[ 2; c o en,]^1 : 2-Dinitrodiethylenediaminecobaltic salts.65811 /I-- ' en\ I and1 : 2-Dichlorodiethylenedianiinecobaltic sal ts.6665 A.Werner, Ber., 1911, 44, 2445 ; A . , i, 838.ti6 A. Werner, ibid., 3279; A., 1912, i, 10ORGANIC CHEMISTRY. 83In each series resolution was effected by a method resemblingthat used with the analogous chloronitro-salts. It consists inthrowing out of solution the more sparingly soluble camphor-sulphonate or bromocamphorsulphonate by the help of theammonium salts of the two acids, the relative solubility of thesalts of the active radicles being found in all cases to be reversedin the case of the two acids, that is, if the d-camphorsulphonate ofthe lEvo-base is the less soluble, the d-bromocamphorsulphonate ofthe dextrocbase is the less soluble, and vice versa; for example,Z-dinitrodiethylenediaminecobaltic d-camphorsulphonate is sparinglysoluble, whilst the corresponding salt of the d-radicle is easilysoluble ; on the other hand, when d-bromocamphorsulphonic acid isused, the less soluble salt is that yielded by the d-radicle.Thed-camphorsulphonate of the Z-radicle and the d-bromocamphor-sulphonate of the d-radicle can thus be obtained pure, and servefor the preparation of their salts.The observed specific rotations of the 1 : 2-dinitrodiethylene-diaminecobaltic salts are of the same order as those observed withthe active chloro- and bromo-amminediethylenediaminecobalticsalts; for example, in 1 per cent.solutions the following wereobtained 67 : chloride, [a], +$.”; bromide, [a], +“,?.The active 1 : 2-dinitrodiethylenediaminembaltic salts show a, verypronounced anomalous rotation dispersion, the D line being stronglyrotated, whereas the C line is rotated to a very small extent or nota t all.The rotatory power of the active dichlorodiethylenediamine-cobaltic salts is very much greater than that of salts of the otheroptically active cobalt series ; for example, for the chloride,[C12Co enJC1, [a] i::::.- Whilst ~ the- chloroammine-, bromoammine-, and dinitro-cobalticsalts are stable in aqueous solution and show a constant rotatorypower, the rotatory power of the dichlorocobaltic salt diminishefivery rapidly, and as a rule after some hours completely disappears.This is due to the action of the water used as solvent, for in thedry state their activity remains unchanged. The auto-racemisationof these salts is connected witch the fact that the dichloro-salts take67 A.Werner, Ber., 1911, &, 2445 ; A . , i, 538.G 84 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.up water, being converted into the chloroaquo- and diaquo-salt,s,thus :andCl,+H,O = [H20Co H2O en2]C1,.Whether it is a consequence of the formation of a trans-compoundor of some other kind of change has not yet been decided.In certain cases the two intracradicle chlorine atoms of thedichlormalts can both be replaced by other acid residues withoutloss of optical activity.This is brought about, for example, by theaction of potassium carbonate, which causes the formation of acarbonatdiethylenediaminecobaltic salt. By this replacement,which can be formulated thus:[Ci,Co en,]^^ + K(,CO, -+ OC<~>CO * en2 1. [there is formed an active carbonato-salt which is relatively easyto isolate. The direction of rotation of the carbonatocsalt formedis opposite to that of the dichloro-salt from which it is produced.The experimental evidence given so far has been of a positivecharacter.The theory, however, also requires that compoundsof the composition [A,Me en2]X,in which the A radicles are in thetrans-position, should not exist in optically active form.I n agreement with this predict’ion Werner has shown68 that itis not possible t o separate the 1 : 6-dinitrodiethylenediaminecobalticsalts which have the nitregroups in the trans-position, thus :NO2 ld07 I““1I NO,into active components, although a splendidly crystallised camphor-sulphonate of this radicle can be obtained.Werner 69 notes that the mirror image isomerism of compoundsof the second type is of a, simpler nature than that of the first,inasmuch aa a less number of distinct groups are involved.H e considers that compounds of type I contain an asymmetriccobalt atom, whilst compounds of type I1 possess a kind ofmolecular asymmetry, which he designates as molecular asym-metry I, since the octahedral formula admits of still other kinds ofmolecular asymmetry. The distinction, however, can scarcely be68 A.Werner, Ber., 1911, 44, 2454 ; A . , i, 839.69 A. MTeriier, ibid., 2446 ; A., i, 839ORGANIC CHEMISTRY. 85justified. What is established .in both cases is the fact that ametallic atom can act as the central atom of a stable asymmetricallyordered molecule, in which there exists no plane of symmetry, andit might perhaps be well to abandon the current mode of speakingof an asymmetric atom, reserving the term asymmetric for theentire molecule, to which alone it can be consistently applied.The results above outlined show that Werner’s conception ofthe octahedral structure of these compounds is capable of with-standing the severest tests to which a theory can be subjected, sinceit continually leads to predictions which subsequent experimentsmost strikingly verify.They also appear t o negative the idea that there is any realdifference between ordinary compounds and the so-called molecularcompounds.The cases of isomerism known up to the present time among thediacidodiethylenediaminecobaltic salts are summarised by Werner 70as follows :(1) Cis-tram-isomerism :Flavo-salts.(2) Salt-isomerism :Croceo-salts.1 : 2-Dinitritodietliylene- Flavo-salts.diaminecobal ti-salts.and also the 1 : 6-dinitrodiethylenediaminecobaltic salts and thec r oceo-salts .(3) Ionisation metamerism :etc.X can be either C1, Br, or SCN,(4) Co-ordination polymerism :(5) Mirror image isomerism :d- and [(2) ( l ) O%o 0,N en2]X.Asymmetric Chromium Compounds.As the co-ordinated compounds of chromium show great analogywith those of cobalt, the discovery of optically active cobalt deriv-70 Ber., 1911, 44, 2449 ; A , , i, 84086 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.atives led to the conclusion that the corresponding chromiumcompounds, if obtainable, should be similarly capable of resolutioninto optically active components. Although up t o the present nogreat number of chromium compounds have been prepared whichshould theoretically exhibit optical isomerism, Werner 71 has suc-ceeded in resolving the members of one series, the 1 :Z-dichloro-diethylenediaminechromic salts of the composition [Cl,Cr en,]X,into their optically active components.The complex radicles of the two enantiomerides are representedby the configuration formuk :2'1 ClI & I/ /\ c1 "\I --and shows molecular asymmetry I, similar t o that observed in thecase of the 1 : 2-dinitro- and 1 : 2-dichloro-diethylenediaminecobalticsalts.Like the corresponding cobaltic salts, the 1 : 2-dichlorodiethylene-diaminechromic salts are very unstable in aqueous solution, as theyvery readily take up water and pass over into the chloroaquo- anddiaquo-salts, thus : [z: Cr en2]Cl + H,O = [t;" Cr en,]^^,,[$O Cr en,]^^^ + H,O = [:$ Cr en,]^^,.Owing to this circumstance, resolution with silver d-bromocam-phorsulphonate could not be effected.A method resembling thak used in the case of the analogouslyreactive cohaltic salts was, however, successful.It was found that when ammonium d-bromocamphorsulphonatewas added to a freshly prepared saturated solution of racemic1 : 2-dichlordiethylenediaminechromic chloride, perfectly purecrystals of the d-bromocamphorsulphonate of the, Iaevo-radicle quicklyseparated, whilst when ammonium I-bromocamphorsulphonate wasemployed, d - dichlorodiethylenediaminechromic I - bromucamphor-sulphonate was similarly thrown down.From these sulphonates thechlorides, bromides, and nitrat'es of the two active radicles wereprepared.For the optical rotation the following values were obtained:chloride, [a] ;;g; bromide, [a] q:z; nitrate, [a] ;:$.The activedichlorodiethylenediarninechromic salts very quickly lose their.71 A. Werner, Ber., 1911, 44, 3231 ; A. i, 951ORGANIC CHEMISTRY.activity in aqueous solution; but the cause of this has not yet beenfully cleared up.The active chromic salts show it much smaller rotatory powerthan the corresponding cobaltic compounds, the difference inmolecular rotation being about 140-150°, from which it followsthat the rotatory power is dependent, not only on the nature of thegroups attached to the central atom, but on that of the centralatom itself.Novel Reactions and Others of General Interest.Among the chief reactions to be noticed under this heading aresome new processes for preparing halogen derivatives.The simplestof these consists of treating the corresponding alcohol with twomolecular proportions of thionyl chloride or bromide and one suchproportion of a tertiary base.72 Under favourable conditions themethod gives yields of over 90 per cent., and i t may be appliedto alcohols of various types, for example, isoamyl alcohol, cinnamylalcohol, and esters of hydroxy-acids. An advantage of the methodis seen in the case of ethyl I-malate, where less racemisation takesplace than with the use of phosphorus pentachloride. However,the process cannot be applied to phenols, and, with substancessuch as cyclohexand, dehydration may occur.Another method 73 leads to these halogen derivatives from theprimal7 amines.The benzoyl derivatives of the latter substancesare warmed with phosphorus pentachloride, when the followinginteraction occurs :R*NH*COPh + PCl, = POCI, + PhCN -+ RC1;but this is by no means quantitative, and there is sometimes troublein separating the chloride from the benzonitrile which is alwaysformed. It is recommended that the latter be converted into thecrystalline hydrochloride of benziminoethyl ether, which is verysparingly soluble in alcohol. The process has been applied to mono-and di-amines, the latter substances leading to di-halogen deriv-atives, such as ap-dichlorododecane, which may prove of use inother synthetical reactions. The catalytic bromination of the side-chain in aromatic compounds may be effected 74 with the aid ofozone, but it remains €or future research to decide whether thisagent can be universally applied.An elegant method of chlorinat-ing aromatic substances has been developed from the results ofprevious experiments 75 on the behaviour of N-chloroacylamines in78 G. Darzeris, Compt. rend., 1911, 152, 1314, 1601 ; A., i, 513, 517.73 J. von Braun and W. Sobeckj, Ber., 1911, M, 1464 ; A., i, 597.74 L. Rruner and Z. Lahociriski, BILL?. Acad. Sci. Cracow, 1910, 560 ; A., ii, 242.75 K. J. P. Orton and W. J. Jones, Trccns., 1909, 95, 1456.888 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.presence of hydrogen chloride. It may be recalled from formerreports that when these substances are mixed under suitable condi-tions the reversible change (i):takes place, but if the aromatic nucleus is easily chlorinated afurther irreversible reaction (ii) :Ar-NH*Ac+C12 -+ ArCl'NH*Ac+HC1 ., (ii)sets in. By choosing a chloroanine-such as acetylchloroamino-2 : 4-djchlorobenzene-in which the nucleus is already profoundlysubstituted by chlorine, the further chlorination of that substanceis inhibited, and the action of the free chlorine (ii) is transferredto any other aromatic compound which is present. The methodis admirably adapted to the measurement of the speed of inter-action, and the influence of the constitution of acylamines on theirrenct'ivity has been closely studied76 Moreover, the method permitsthe preparation 77 olf chloro-derivatives from substances which aretoo violently attacked by the usual reagents.I n a new process78 for preparing aliphatic 8-diketones, use hasbeen made of the enhanced reactivity of the acetylenic linkingwhen adjacent to the carbonyl group; thus acetylenic ketones ofthe type (I) rea.dily unite with secondary amines (as in II), andAr-NCl*Ac+HCl g? Ar*NH*Ac+CI, .. (9RC i C* C 0 R R$! :CH*CO*R R C 0 C H CO YL(111.)NR2(1- 1 (11.1when the products are hydrolysed with acid the correspondingP-diketones (111) are formed. A similar reaction may be used toconvert 79 a@-ethylenic ketones (I) into unsaturated alcohols, for thefirst-named substances form additive products with secondaryamines (11), which may be reduced to the secondary alcohols. TheiN e C 0 CR : CH 3Xe-CO*HCR*CH2*NR2(1.1 (11.1latter, when treated successively with methyl iodide and silver oxide,yield the ammonium hydroxides (111), which easily decompose withloss of water and tertiary amine, giving the unsaturated alcoholMe*CH(OH)*CHR*CH,*NR2Me*OH -+ Me*CH(OH)*CR:CH,A new method of inserting the carboxyl group into complex76 K.J. P. Orton and H. King, Trans., 1911, 99, 1370; H. King and K. J. P.77 H. King, Proc., 1511, 27, 266.78 E. AndrB, Compt. rend., 1911, 152, 525, 1488 ; A., i, 268, 545.(IV) :(111.) (IV.)Orton, ibid., 1377.Farbenfabriken vorm. F. Bayer & Co., D.R.-P. 233519 ; A., i, 598ORGANIC CHEMISTRY. 89aromatic hydrocarbons 80 is provided by oxalyl chloride. Thisreactive substance attacks some hydrocarbons, such as anthraceneor phenanthrene, when heated alone with them; but the yields ofcarboxylic acids are better when the cold reagent is employed inpresence of aluminium chloride.Under the latter conditions othersubstances are apt to be formed; thus anthracene yields the newquinone of aceanthrene (I), whilst di-p-tolyl gives 2 : 7-dimethyl-phenanthraquinone (11) :CO-coThe use of the organo-magnesium compounds in synthetical workhas been as extensive as ever, but the discovery of new methods ofapplying this reagent has somewhat abated. With regard to thetheory of the reagent, some confirmation has been found for thehypothesis81 that oxonium salts of the type R,O*X are formedas intermediate substances. I f such exist, it is to be supposed thatin suitable cases some evidence of heterospasis would be found;thus an oxonium salt, R,R’O*X, might decompose in either oftwo mays:ReX+ROR +-- R,R‘O*X --+ R,O+R’*X.Evidence of this decomposition has been obtained82 in the caseof the interaction of magnesium with propyl iodide and triphenyl-methyl ethyl ether in xylene solution.An interesting study of the application of this reagent todihalogen derivatives has been made.83 It is evident that from anormal dihalogen compound (I) a variety of products might beformed, for, on the one hand, if the metal acts merely by removalof halogen, polymethylenes of the structures shown in (11) and (111)Br* [CH,],*Br l-[CH,]n-l I-[CH2], [C H 2]9z-i(1.) (11.1 (111.)might occur in the final product, whilst on the other, open-chainderivatives such as :BrMg*[CH,],*MgBr or BrMg*[CH,], [CH,j,-MgBr~ _____(IV.) (V.1might result.In the cases of ethylene and trimethylene bromidesthe former type of reaction is the more prominent, but it is remark-8o C. Liebermann, BcT., 1911, 44, 202, 1153 ; A , , i, 202, 656.S1 W. W. Tscheliiizeff, A., 1905, i, 40.gL G. L. Stadnikoff, Ber., 1911, 44, 1157 ; A . , i, 435.Sy J. von Rmnn and W. Sobecki, ibid., 1915 ; A., i, 73190 ANNUAL REPORTS ON THE PKOGRESS O F CHEMISTRY.able that with as-dibromobutane and the higher members of theseries this does not take! place, substances of types (IV) and (V)being produced ; thus arc-di-iododecane yielded eicosane and tetra-contane, and a€-dibromopentane yielded n-decane, pentadecane, andeicosane mixed with yet higher homologues.Other applications 84 of this reagent have furnished two newmethods of preparing nitriles, which are obtained by treating themagnesium derivative with cyanogen or its chloride.The employment of peroxides as oxidising agents has continuedt o increase.Among the researches dealing with this type of reagent,that concerning the interaction 85 of organic peroxides with unsatur-ated cornpounds is of particular interest. Benzoyl hydroperoxidereadily reacts with ethylenic derivatives in neutral solvents, givingexcellent yields of the ethylene oxide :0/\C,H,*CO*O*OH + >C:C< = C,H,*CO,H + >C--C<'from which the corresponding glycols may be obtained. A t thesame time it is shown that even in the case of substances containingconjugated unsaturation, an accurate estimate may be formed ofthe number of ethylenic groups present in the original compound.Moreover, the character of the unsaturated group may be inferredfrom the behaviour of the oxide with acid reagents, for those con-taining the *CH-CH, group yie'ld aldehydes, CHO*CH,*, and those\/0containing the structure *CIT--CH* give ketones, -CR,*CO-, by\ /0isomeric change in the presence of acids.Other work with thistype of reagent has dealt with the interaction of hydrogen peroxideand alkaloids, those of the morphine group 86 yielding amino-oxides.With sulphur compounds it has been observed that in the caseof thiobenzanilides7 addition of oxygen to sulphur takes place,whilst with thiophen 88 hydroxy-derivatives of the nucleus areformed.The formation of ozonides and the decomposition of these bywater has been extensively applied to determining the structureof ethylenic compounds, the method being particularly useful in84 V.Grignard, Compt. rend., 1911, 152, 385 ; A., i, 292.85 N. Prileschakeff, J. Rzcss. Phys. Clzcm. S'OC., 1910, 42, 1387 ; A . , 1910, i, 86,86 M. Freund and J1:. Speyer, Ber., 1910, 43, 3310 ; A., i, 76.87 E. de B. Barnett, Proc., 1911, 27, 115.88 M. Lanfry, Compt. rend., 1911, 153, 73, 821 ; A , , i, 740, 1009.255ORGANIC CHEMISTRY. 91the case of the polymerisation products of divinyl and its deriv-ati~es.8~A preliminary investigation has been made90 of the use of silvernitrate as a catalyst in presence of persulphates, and the resultsgive promise of a.n interesting method of obtaining sensitiveoxidation products.On turning to reducing agents i t is evident? that the methodwhich possesses the greatest interest a t the moment is that depend-ing on the contact action of certain metals or their oxides inpresence of hydrogen. I n view of the thoroughness wit,h which thissubject has been treated in the previous report, and of the admir-able summary which has been given by Sabatier91 in an addressto the German Chemical Society, the remarks now made need beonly few and of a general character.As wo'rk proceeds with thismethod, the possibilities of employing i t for selective reductionbecome more and more apparent, I n a comprehensive paperg2dealing with the behaviour of hydroaromatic compounds in thepresence of hydrogen and colloidal palladium, it has been shownthat reduction may be carried out; under conditions which practi-cally exclude intramolecular rearrangement.Moreover, unsaturatedketones containing more than one ethylenic linking may be com-pletely reduced without interfering with the carbonyl groups.Other work93 has shown that by choosing suitable conditions thecyclopropane system can be guarded from reduction, whilstethylenic linkings present are removed. It is further evident thatthe selective action of this type of reagent can be varied by alteringthe temperature of interaction or the pressure of the hydrogen 9 4 ;thus, when phenanthrene vapour and hydrogen are passed overpalladium a t 160°, the octahydride is formed, but if reduction iscarried out a t the ordinary temperature in cyclohexane solutiononly tetrahydrophenanthrene is obtqained.The reduction ofphoroneg5 serves to illustrate the effect of altering the pressure ofhydrogen during the reduction. Using colloidal platinum as thecatalyst, a pressure of one and a-half atmospheres confines thereduction to the ethylenic linkings, but with increasing pressuremore and more complete interaction is obtained :89 C. D. Harries, Annalen, 1911, 383, 157 ; A . , i, 798 ; S. V. Lebedeff, J. Rzcss.Phys. Chem. Soc., 1910, 42, 949 ; A., i, 26.9~ P. C. Austin, !Fra??s., 1911, 99, 264.91 P. Snbatier, Rer., 1911, 44, 1984 ; A . , i, 702.92 0.Wallnch, Annnben, 1911, 381, -5l ; A., i, 469; G. Vavon, Compt. rend.,93 L. A. Tschugaeff, Comnpt. rend., 1910, 151, 1658 ; A . , i, 72.g4 P. Breteau, ibid., 1368; A , , i, 123.95 A. Skita and H. Ritter, Ber. 1910, 43, 3393 ; A., i, 71.1911,152, 1675 ; A . , i, 65792 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.1-5 ata. (Eg3>CH*CH2) CO c C H s > ~ : ~ ~ - ~ ~ - ~ ~ : €1, c<::; -+3 2Phorone. Valerone.2 ats. -+ ( ~ ~ ~ > c H ~ c H , ) CH-OH3 2Diisobutylcarbinol.CHS>CH-OH 5 ats. --+ c4a9Methylisobutylcarbinol.Active search is being made for other catalysts which mightreplace the more expensive platinum or palladium, and amongthose discovered especial mention may be made of copper and itsoxide.96 The experiments with these substances were carried outby heating the unsaturated compound with hydrogen and thecatalyst in an iron tube; but the remarkable fact was observedthat with tubes of copper no reduction took place, whence i tappears that two catalysts should be simultaneously present.I nany case, however, copper oxide is not so efficient as nickel oxide.Attention may be here directed to the interesting fact that thesame catalyst obtained in different ways may lead to varyingresults. A recent example of this behaviour is the reduction ofa-pinene with palladium at the ordinary temperature.97 When thecatalyst is prepared from palladium ammonium chloride with formicacid in the presence of alkali, reduction proceeds normally to hydro-pinene, but with palladium made from palladous chloride and thesame reagents, isopinene is formed.This is one of the few cases ofintramolecular change which have been observed with this reducingagent, and it is probably due to subsequent oxidation of the hydro-pinene formed in the preliminary stages of the action.There is a general desire among organic chemists to explain theaction of these catalysts by the formation of some intermediatesubstance; for example, in the case of nickel 98 it is probable thatsome unstable hydride is formed, which easily yields hydrogen tosubstances brought into contact with it. This conception furnishesan explanation of the oxidising power exerted by the metal whenheated aIone with a saturated substance, for hydrogen and theunsaturated derivative are then formed.In fact, it is probablethat during all these catalytic reductions the reverse action 99 takesplace at the same time, and in many cases by choosing conditionsone or other process may be made to predominate. Many experi-96 W. N. Ipatieff, Bey., 1910, 43, 3387, 3545 ; A., i, 31, 137.97 N. D. Zelinsky, ibid., 1911, 44, 2782; A., i, 997.9E Sabatier, ibid., 1998 ; A . , i, 702.g9 A. Skita and H. Ritter, ibid., 668 ; A., i, 272 ; N. i). Zeliiislry and N. Gliuka,ibid., 2305; A . , i, 870 ; N. D. Zelinsky, ibid., 3121; A., i, 958ORGANIC CHEMISTRY. 93ments have shown that the presence of oxygen in the nickelemployed has a favourable influence on the course of the reduction;this circumstance has been explained by assuming that the waterformed from the oxide and hydrogen immediately attacks thereduced nickel with renewed liberation of hydrogen in an activecondition.When working with liquids at the ordinary temperaturei t has been suggested 1 that subst.ances of the following type (I) areR’CH--CHR’(1.1 \/ -+ RCH,*CH,R’ + M(0H)YnH,M(OH)mformed, which pass into solution in the colloidal state, and thendecompose as indicated, regenerating the oxide and liberating thesaturated substance .More recent research has tended t o complicate rather than tosimplify the question of the catalytic mechanism. It has beenpointed out 2 that all metals which behave as reduction-catalystscontain small quantities o€ oxygen, and the opinion has beenexpressed that the various metallic hydrides merely convert thisinto the hypothetical perhydride of oxygen, OH,, which then maydecompose into oxygen and hydrogen, and so furnish the materialeither for reduction or for oxidation.Against this hypothesis the consideration may be offered thatany agent which is capable of reducing oxygen to this extent wouldalso probably be sufficiently powerful to reduce unsaturated carbon,so that so far as reduction is concerned the assumption appearsto be unnecessary. In the present state of affairs the simplerexplanation forms a quite satisfactory working hypothesis, and, inthe opinion of the writer, it will be difficult to overthrow withoutquantitative experiment.For better illustration of the specific action of contact substancesi t is necessary to turn t o the interaction of alcohols and acids inpresence of metallic oxides.In decompositions of this type it wouldbe almost impossible, without assuming the formation of derivativesof the catalyst, t o give a satisfactory account of the origin of thediverse products. The question has been very carefully studied.3When a mixture of an alcohol and an acid are passed over a hotoxide (MO) which functions as the catalyst, four different types ofinteraction may take place:I. N O + 3R*C02H = H20 + (WCO,),M = MO + CO, + H, + R*CO*R.11. MO + 2C,Ha,+iOK 2 H20 + (C,H2fi+10)2M.iII. M(OC,H2,t+1)2= MO + H,O + 2C,Hzn.I V. M(OC,H2,+1).L + 2R*C02H = MO + 2R*CO2*C,H2,+1 + H,O.S. Fokin, J. Guss. Chern. Phys. Soc., 1910, 42, 1074; A., i, 1.N.D. Zelirisky and N.Glinka, Zoc. cit.P. Sabatier and A. Mailhe, Compt. rend., 1911, 152, 358, 494 ; A., i, 20894 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.An explanation of the varying results with different acids andcatalysts is found on considering these various interactions. Gener-ally speaking, the yield of ester depends on whether the acid readilyundergoes the first of these decompositions; if it does not, thenester-formation (IVj predominates, and reactions (I), (IIZ and (111)are negligible. I n the presence of thoria at 400°, acetic acid readilyinteracts according to ( I j ; hence the amount of ester obtainedunder these conditions is small, all four types of decomposition thenoccurring. The yields of ester may be very much improved bychoosing an acid, such as benzoic, which does not easily give theketone decomposition (I) ; in such a case the formation od esterswith fatty alcohols almost accords with theory, being as high as95 per cent.On the other hand, the same result may be attainedby chofosing a catalyst, such as titanium oxide at 280-300°, whichdoes not decompose the acid (I); and by adopting this plan goodyields of the esters of acetic and other fatty acids may be obtained.Another method of attaining the desired esters is to modify thetemperature of interaction; thus with thoria a t 150° even formic4acid may be esterified.The catalytic decomposition of esters, which forms the reverseaspect of this question, has also been studied.5 Hydrolysis of theester will take place as follows:and it is shown that the stability of these products in presence ofthe catalyst will determine the nature of the ensuing decompmition.According to theory three cases are possible.I f the alcohol andacid are equally stable in respect to the catJalyst, the ethylenichydrocarbon and the ketone will be simultaneously produced ; if theacid is the less stable, the ketone will appear in larger quantitywith the alcohol, and some of the unsaturated compound; whilst i fthe alcohol is the less stable," the bulk of tlie product will consistof the ethylenic derivative, and only a small amount of ketonemay be formed. I n this manner the varying types of decompositionobserved with esters in presence of different catalysts may be satis-factorily explained.The discussion or" many o€ these cases wouldbe of interest, but this is precluded by considerations of space andthe nature of this report; however, it is hoped that enough hasbeen said to show the state of development which the theory ofthese catalytic actions has attained during the past year. On theother hand, the practical application of the catalytic method hasP. Sabatier and A. Mailha, Coinpt. re71d., 1911, 152, 1044 ; A., i, 416.P. Sabatier and A. Mailhe, ibicl., 669 ; A,, i, 348.6 See W. N. Ipatieff, Ber., 1910, 43, 3383; A., i, 25ORGANIL CHEMISTRY. 95been extended to the preparation of phenolic ethers,’ amines? andunsaturated hydrocarbons.9 Finally, it may be remarked that aperusal of the patent literature of the past two or three years willconvince the reader of the general value of the process.J.E. Marsh10 has obtained liquid compounds of certain halogendouble salts with ether. Among the salts which give such liquid com-pounds are lithium, sodium and potassium mercuri-iodides, lithiummercuribromide, j ithium silver iodide, and lithium cuprous iodide.These liquids take up only a limited amount of ether, and arenearly insoluble in excess of ether. The potassium mercuri-iodidecompound was mentioned in last year’s report.ll Some of thehalogen double salts also bring about a complete mixture of etherand water, f ormiiig a homogeneous solution. I f these ether-aqueoussolutions are warmed, they may separate into two, and even intothree, Iistinct solutions, forming separate layers in it tube, whichare permanent if the temperature is kept constant, and becomemiscible again on cooling. Among the salts which have been foundto give ether-aqueous solutions separating into three layers onwarming are sodium, potassium, and rubidium mercuri-iodides,ammonium mercuribrornide, and lithium mercurichloride.Thisseparation into layers can be explained with the help of the theoryof Le Chatelier 12 and of van’t Hoff.ls Ether dissolves potassiummercuri-iodide with evolution of heat ; water dissolves it withabsorption of heat. Moreover, heat is given out when ether is mixedwith the aqueous solution and when water is mixed with the ethersolution. Hence on warming the homogeneous solution, it tends toexpel ether and water, and also to drive the salt out of the etherinto the water solution; thus the three layers consist of a weakether solution, an ether-aqueous solution, and a strong watersolution, the latter containing excess of potassium iodide, since thesalt itself is partly separated into its constituents.Werner l4 has discovered a remarkable series of group-inversionsanalogous in some respects to the Walden inversion.These inver-sions take place among the diethylenediaminecobaltic compounds,and consist in a conversion of the cis-form into the tram-, and thetrans-form into the cis-. According to Werner’s theory, the cis-and trans-form are represented by the following models, where7 A. Mailhe, Chcm. Zeit., 1911, 35, 485.* A.Mailhe, ibid., 1910, 34, 1173, 1182, 1201.lo T~ans., 1910, 97, 2293 ; PTOC., 1911, 27, 328.l2 Compt. rend., 1885, 100, 441 ; A . , 1885, 473.l3 Arch. Nkcrland, 1886, 20, 53.l4 Ber., 1911, 44, 873 ; A . , i, 424.W. N. Ipatieff, Ber., 1910, 43, 3383 ; A . , i, 25.Ann. Aeport, 1910, 3596 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the six groups occupy the angles of an octahedron, of whichcobalt atom occupies the centre:X XthexCis-form, 1 : 2. Trans-form, 1 : 6.en = NH,*CH,-C'H,*NH,.There are three types of reactions by which the change is broughtabout : (1) substitution reactions, (2) additive reactions, (3) disrup-tive reactions. The follolwing examples will serve to illustratethem.(1) Substitution reactions :(2) Additive reactions :CWISNco en2 GI,.1 [[l; Ei Co en,]CI + NH, =(3) Disruptive reactions :That we have not to do here with the formation of the onlypossible isomeride, or even of the most stable isomeride, is shownby the bahaviour of the isomerides themselves, for example : [[:I :i Co eo,]X gives with potassium hydroxide [[li :$ Co en2 X,, I andX gives with ammonia [(I) Ho Co en,]X,.(6) *2OSometimes also the reactions result in the formation of a mixtureof both the cis- and trans-isomerides. . Further, some groups, suchits halogens, NO,, NCS, enter more readily than others into theoctahedral sphere of attraction of the cobalt, and this entrance orexit is dependent also on the nature of the acid group or ionwith which the cobalt complex is associated.In reactions of sub-stitution there is evidence that the reagent which is going to bringabout the substitution forms, in the first place, an additivORGllNiC CHEMlSTRY. 97compound with the cobalt complex, an additive compound whichit is in some cases possible to isolate; for example, the compound [EN Go en,]NO, gives with silver nitrate a compoundSCNwhich is soluble in water and precipitated by nitric acid; onwarming the solution, silver chloride is precipitated.ZEings containing six carbon atoms have long been known tounite directly with one another in two ways. I n omne the rings areunited by one carbon atom of each ring, as in diphenyl. I n theother the union is effected by means of two carbon atoms commonto both rings, as in naphthalene and phenanthrene.So far, however, no hydrocarbon has been described in whichtwo benzene rings are directly united by the linking of two carbonatoms of one ring to two carbon atoms of another.Special interest therefore attaches to the preparation ofdiphenylene, C6H,:C,H,,A-/\I 1-1 I -\/ \/This was obtained in almost theoretical amount by heating anethereal solution of 2 : 2/-dibromodiphenyl with sodium until allaction ceased.15 The constitution of the hydrocarbon follows fromits mode of preparation, its molecular weight, and from the factthat i t yields phthalic acid when oxidised by chromic acid mixture.Acetylene is slowly absorbed by iodine at about 150°, and amixture of two isomeric di-iodides is obtained.This can beseparated into a solid and a liquid isomeride.lG Fumaric acid havingbeen obtained from the solid compound by means of potassiumcyanide and hydroxide, it has usually been regarded as the trans-or fumaric form, and the liquid isomeride as the cis- or maleicform :Solid acetylene di-iodide(melts at 73").Liquid acetylene di-iodide(boils at 185").This view has now been confirmed,l7 and it has been shown thatsolid acetylene di-iodide can be converted into fumaric acid, andits liquid isomeride into maleic acid.The differences of opinion which show themselves whenever diazo-compounds are under discussion indicate that up to the presentno general agreement as to their constitution has been reached.l5 J.J. Dobbie, J. J. Fox, and A. J. H.Gauge, Tmiis., 1911, 99, 653.16 E. H. Keiser, Arner. Chern. J., 1899, 21, 261 ; A., 1899, i, 398.E. H. Keiser and L. McMaster, ibid., 1911, 46, 518 ; A . , i, 949.REP. -VOL VIII 98 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Morgan and Miss Blicklethwait18 note that all the availableevidence strongly supports the assumption that the diazotisabilityof a base depends on the association of its amino-group with anunsaturated organic complex. This complex need not necessarily bearomatic or even cyclic, but it is, apparently, essential that it shouldbe unsaturated, for hitherto no amine possessing a fully saturatedradicle has ever been diazotised. The existence of a certain degreeof residual affinity is a necessary condition for the production of adiazonium salt.Among aromatic compounds this residual affinity is supplied bythe fourth valency of each carbon atom of the six-membered rings.The authors conclude that maximum stability of the diazoniumsalt results when the residual affinities of the organic radicle andthe diazonium complex satisfy each other t o the fullest extent.I n an aromatic moriodimnium salt the residual affinity of thenitrogen atoms is availlable for saturating the six fourth valenciesof the carbon atoms.Acetaldehydephenylhydrazone was first obtained from the inter-action of acetaldehyde and phenylhydrazine by E.Fischer, whoshowed 19 that it could exist in two forms, and possibly in a third.The smcalled @-variety having the lower melting point wasobtained by distilling under diminished pressure the originalproduct. This was transformed into the a-variety having a muchhigher melting point by boiling an alcoholic solution for a fewmoments with a little sodium hydroxide. When recrystallised undercertain undetermined conditions a product of lower melting point,regarded as possibly a third form, was frequently obtained.Lockemann and Liesche some years later 2o carefully examined thecompound, and found that it really existed in two modifications:a stable form termed the a-modification melting a t 98-101°, and alabile form termed the @-modification melting a t 57O.They foundthat the latter gradually changes into the a-modification, but thatthe transformation is hastened by the action of bases such assodium hydroxide or ammonia.The change from the a- to the&form is effected very rapidly by treatment with aqueoussulphurous acid. These interesting phenomena have been recentlyre-investigated by E. G. Laws and N. V. Sidgwick.2i They find thatin the preparation from aldehyde and phenylhydrazine a variablemixture of the two modifications is obtained. The a-forrh (m. p. 9 8 O )is best obtained by carefully crystallising the original material fromaqueous alcohol containing a trace of potassium hydroxide, and theG . T. Morgan and MissF. M. G. Micklethwait, Tmtis., 1910, 97, 2561.I9 Ber., 1896, 29, 795 ; A., 1896, i, 361.2o A?ma;Ze?z, 1905, 342, 14 ; A., 1906, i, 111.21 Truns., 1911, 99, 2085ORGANIC CHEMISTRY. 99@-modification (m. p. 5 6 O ) by similar crystallisation from the samesolvent containing a trace of sulphur dioxide.Acetaldehydephenyl-liydrazone thus possesses the remarkable property that either formcan be converted into the other almost quantitatively by the actiouof a mere trace of acid or alkali.Transformation also is easily brought about without any appreci-able alteration in the appearance of the crystals by exposing 8- ora-crystals to an atmosphere of ammonia or sulphur dioxiderespectively.No change of optical properties could be recognised when afairly large crystal of the a-modification was converted into the&modification under the influence of a drop of acid.The peculiarity of the isomerism is obviously connected with thevery small difference in energy content, and therefore in the relativestability of the two forms.On the other hand, there can be nodoubt that the a-form is more stable in presence of alkali and thep- in presence of acid, and that a trace of acid or alkali can bringabout a change from one to the other, proceeding through a massof crystals without their passing into solution. It therefore followsthat there is a difference between crystals in contact with acidand crystals in contact with alkali. This can only come about byadsorption of acid or alkali into the crystals, which causes adifference in energy greater than the difference between the twoabsolutely pure forms.Distillation in steam or recrystallisation yields an equilibriummixture of the two forms. There seems to be little ground for theauthors’ conclusion that the modifications are stereoisomerides.s-Dichlorocarbamide, NHCl*CO-NHCl, was obtained Z2 some yearsago by passing chlorine into a cold saturated aqueous solution ofcarbamide ; monochlorocarbamide, NH,*CO*NHCl, the formation ofwhich must precede that of dichlorocarbamide, has recently 23 beenprepared in a similar manner by passing the requisite amount ofchlorine into an aqueous solution of carbamide, and cooling inmethyl chloride.The compound resembles in properties the moreeasily prepared s-dichlorocarbamide, but is more soluble in water.It has been shown24 that when phenylhydrazine is heated underordinary atmospheric ptessure to its boiling point, 241-242°, itdecomposes comparatively rapidly into aniline, ammonia, nitrogen,and benzene, thus:2C6H5*NH*NH2 = C,H,*NH, + NH3 + N, + C,H,.2~ F.D. Chattaway, Proc. Boy. Soc., 1908, 81, 381; Chent. News, 1908, 98, 285;23 A. BBhaland A. Detcmf, Compt. rend., 1911, 153, 681 ; A . , i, 957.Trans., 1909, 95, 129.F. D. Cliattaway and M. Aldriclge, Trmw., 1911, 99, 404.H 100 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Other aromatic hydrazines when heated undergo similarly simul-taneous oxidation and reduction. As the precise course of any suchaubreduction depends only on the group to which the hydrazineconcerned belongs, these interactions may be expressed by generalequations.Primary hydrazines yield a primary amine, nitrogen, ammonia,and a hydrocarbon:2R*NH*NHa=RNB,+ N,+ NH, + RH.Unsymmetrical secondary hydrazines yield a secondary amine,nitrogen, and ammonia :3RR’N*NH2 = 3RR’NH + N, + NH,.Symmetrical secondary hydrazines yield a primary smine and anazclcompound :2RNH*NHR’= RNH, +- R’NH, + ItN:NR’.Desmo tropic Sub s t a m e s .During the past year our knowledge of this important apd interest-ing group of substances has been considerably enlarged, and, takinga general view of the discoveries made, it may be said that researchhas proceeded in three chief direct’ions.New experimental processeshave been devised for the isolation of desmotropic forms in thepure condition, quantitative methods have been applied to theanalysis of equilibrium-mixtures or to determining the speed ofinterchange of the isomerides, and several new examples of thistype of substa.nce have been discovered.It has long been known that the speed with which equilibriumis attained in allelotxopic mixtures is retarded by decrease intemperature, but the logical development of this relation has onlyrecently been realised by Knorr, who has skilfully applied thetechnique of low temperature work t o the isolation of the pureisomeric forms of acetoacetic e~ter.~5 The ketonic form of aceteacetic ester hax been isolated in the crystalline state by coding to-80° solutions of the ordinary ester in suitable media; but thepure product, which does not exhibit the ferric chloride reaction, canonly be preserved a t low temperatures.zven at the atmospherictemperature the change into the enolic form begins.To obtainthe latter substance the pure sodium salt of the ester is suspendedin the cold medium and treated with less than a molecular propor-tion of dry hydrogen chloride. The difficulty of preparing thisisomeiide is very much increased by the necessity of performingat the temperature of -78O all operations such as filtration of the25 L. Knorr, 0. Rothe, and H. Averbeck, Ber., 1911, 44, 1138, 2767 ; A., i, 516,976OKGANIC CHEMISTRY. 101reacting mixture and evaporation of the solvent, for the substancechanges into the ketonic form some fifty times more rapidly thani t is formed from the latter. It is noteworthy that, in accordancewith previous experiments26 on other types of tautomeric change,the presence of slight impurities emanating from the glass of thevessels employed or from the atmosphere may enormously increasethe speed of isomerisation.The isolation of these isomerides in the pure condition has ledto renewed discussion of the composition of the equilibriummixtures of acetoacetic ester, but the results obtained by differentworkers are jmt strictly concordant.The simplest method employedin determining the relative quantities of the isomerides present isto compare27 the refractive index of the mixture with those of thepure isomerides or artificial mixtures. The results show that theequilibrium mixture in the case of acetoacetic ester contains about2 per cent. of the enolic isomeride. It is noteworthy that thisprocess is more trustworthy than the previous application of refrac-tive power t o the problem, for i t does not involve the assumptionof a theoretical value for the enolic compound which is certainlyinaccurate ; moreover, experimental sources of error appear t o befewer than in other methods recently devised for the same purpose.One of the latter is based on the observation28 of Lapworth thatthe enolides very rapidly react with bromine, forming the bromin-ated ketones, and it is shown 29 that the latter may be quantitativelyreduced to ketones by hydriodic acid, iodine being liberated.Accordingly, to determine the quantity of enolic isomeride presentin a semple of the ester, a cold solution of the latter is mixed withan alcoholic solution of bromine, &naphthol being immediatelyadded to rernove excess of this halogen; potassium iodide is thena.dded, and, the solution having been warmed, the free halogen istitrated in the usual manner.Experiments with acetoacetic estergave results showing the presence of about 74 per cent. of the enolicisomeride. There is no doubt that the chief source of error in thisprocess is the transformation of the ketonic into the enolic formafter the latter has been removed from the equilibrium mixtureby conversion into bromo-ketone. It is true that the process canbe very rapidly performed, and that the author of the methodestimates the maximum error from the source mentioned at aboutone-fifth per cent. ; but it nevertheless seems impossible accuratelyto gauge the error thus introduced until blank experiments have26 T.M. Lowry, Trans., 1903, 83, 953.27 L. Knorr, 0. Rothe, and H. Averbeck, Zoc. cit.z3 A. Lapworth, Trans., 1904, 85, 30.K. H. Meyer, Annalciz, 1911, 380, 212; A., i, 350 ; K. H. Meyer and P.Kappelmeier, Ber, 1911, 44, 2718 ; A . , i, 832102 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.been made to find the rate of enolisation in presence of the sameconcentration of free hydrobromic acid. In fairness, however, itmust be added that a recalculation of the data obtained byHantzsch 30 in his spectroscopic investigation is stated 31 to lead tothe same result, but it is impossible to form an estimate of theweight of this evidence until fuller details are published.Yet a third method32 has been proposed for the estimation ofthe relative amounts of the tautomeric forms present in a mixture,and, although it has not yet been applied to the case of acetoaceticester, it is worthy of description.Use is made of the fact that thecolour produced by the interaction of ferric chloride and an enoliccompound reaches a maximum intensity when equimolecularproportions of the reagents are present, the interaction being asexpressed by the following equation :R*OH + FeCl, = FeCl,*OR + HCl.Standard solutions are made from the pure enolide and therequisite proportions of ferric chloride, and these are compared ina colorirneter with solutions of the desmotropic mixture containinga corresponding amount of the iron salt. I n this connexion it isinteresting to notice that Knorr has succeeded in obtaining thepure ferric salts of the enolides-(RO),Fe--by decomposing thesodium derivatives with ferric chloride in ethereal solution ; thesemay be employed in preparing the standard solution of ferric mono-enolides by mixing them in suitable solvents with ferric chlorideand hydrochloric acid in the proportions required by the followingequation :Fe(OR), + 3FeC1, + 3HC1= 3FeCl,*OR + 3HC1.This scheme of estimating the enolic isomeride has been appliedwith int>eresting results to methyl mesityl-oxide-oxalate in solutionand in the fused condition.Although it is evident that the complete investigation has notyet, been published, in criticism it may be submitt.ed tlhat themethod is probably limited in application to substances, such asthat mentioned above, which are not too rapidly enolised.Experi-ments from another source with acetoacetic ester indicate thatferric chloride acts on that substance as a powerful enolisingagent 33; a t the same time it is noteworthy that a complete studyof the conditions has shown that the process of enolisation involvesa unimoleculai reaction-a result in harmony with the conclusion30 I<. H. Meyer, Eoc. cit.31 A. Hantzsch, Ucr., 1910, 43, 3049: A . , 1910, i, 811.32 L. Knorr and H. Scliubert, ibid., 1911, 44, 2772 ; A., i, 948.33 K. H. Meyer, ibid., 2725 ; A., i, 833. See, however, A. Hantzsch and C. 11.Desch, Annulen, 1902, 323, 1 ; R., 1902, i, 708ORGANIC CHEMISTRY. 103previously attained by Lapw-orth in studying the action of brominewith these substances.Other enolising agents have been studied, and attention may bedirected to the influence of iodine in presence of mineral acids.Experiments $4 made with this reagent and ketones of the structureR*CO-C,H,,+, have shown that the rate of enolisation dependson the nature of the alkyl groups present.In comparison withthose of normal structure the isoalkyl grouping exerts a markedrestraining influence ; indeed, in general character the relationsappear to be similar to those obtained by other methods of measur-ing the activity of the carbonyl group, such as the rate of additionof bisulphite35 and of oxime formation,SB and the selectiveabsorption of light.37The question of the influence of the solvent has also receivedattention. Experiments 3 made with the ethyl ester of 5-hydroxy-1-phenyltriazolecarboxylic acid (I) :N € ' h < ~ ~ ~ > U *CO,Et NPh<:?i>CH*CO,Etin numerous solvents show that the velocity of isomerisation of thissubstance and the state of equilibrium do not depend on thedielectric constant of the solvent, but are influenced by the relativesolubilities of the isomerides. Without the fortunate discovery ofthe desmotropic pair :(1.)Neutral. Acid.ethyl 5-amino-1-phenyltriazolecarboxylate and ethyl 5-anilinotri-azolecarboxylate, some difficulty would have been experienced inobtaining isomerides of a, nature permitting the accurate determiria,-tion of this induence. With the substances in question it was foundthat the specific influence of a solvent on the equilibrium is afunction of the solubility of the reacting substances, and it isremarkable that this relation has been already deduced by van'tHoff from theoretical premises.Expressing this law in generalterms it may be said that two isomerides which are mutually inter-convertible attain equilibrium in any given solvent when the relationbetween the ratio of their concentrations and the ratio of theirsolubilities reaches a certain value; the latter is called the absolute3J H. M. Dawson and R. Wheatley, Trans., 1910, 97, 2048 ; H. M. Dawson and€1. Ark, ibicl., 1911, 99, 1740.35 A. 11'. Stewart, ibicl., 1905, 87, 185.37 A. \V. Stewart aucl E. C. C. Baly, ibid., 1906, 89, 480.38 0. Dimrotli, Annalen, 1911, 377, 127 ; A., ii, 31.36 Ibid., 410104 ANNUAL REPORTS ON THE PROGRESS OF CHEMIS'I'RY.equilibrium constant, and i t is independent of the nature of thesolvent.Assuming the truth of this law, further deductions maybe made concerning the velocity of change of an isomeride; it thenappears that this is either inversely proportional to the solubilityof the reacting isomeride o r directly proportional to the solubilityof the isomeride which is being formed; but it must be observedthat accurate experimental data in s u p p ~ r t of this relation arestill wanting. The influence of concentration of the equilibrium ofacetoacetic ester in various solvents has been examined39 with theaid of the titrimetric process described in a foregoing paragraph.The results indicate that the enolic form of the ester present insolution increases as dilution proceeds, whence i t follows that theequilibrium depends on the concentration.An attempt to explainthis circumstance has been made by taking into consideration thefact that the solvent varies during the series of measurements, beingcomposed of varying amounts of ester and pure solvent. ToharmoniFe the results with the theory deduced from the behaviourof the triazole derivatives i t seems necessary to assume that additionof the ester increases the solubility of the ketonic form, and soaugments the proportion of that isomeride; but experiments toverify this assumption have not yet been made.I n concluding this short review of new research dealing withdesmotropic substances, mention may be made of the isolation ofthe isomeric forms of some of the more common representatives ofthis class.The methyl ester of benzoylacetic acid 4O when cooled to- 7 8 O yields the crystalline enolic isomeride, and not, as withacetoacetic ester, the ketonic form. The latter, however, is rapidlyformed from the enolide a t the atmospheric temperature, equilibriumbeing reached with varying speeds according to the nature of theglass in which t>he substance is contained. Also acetylacetone yieldsthe crystalline enolide, which likewise undergoes rapid ketonisation.Other work has dealt with anthranolY4l from which the two desmo-tropic forms :(1.1 (11.1ha,ve now been isolated. The substance, which is obtained by reduc-ing anthraqujnone with acid reagents, appears to be the pureketonic isomeride, anthrone (I) ; but when the ice-cold alkalinesolution is mixed with acid, the phenolic derivative, anthranol (11),L.Knorr, Ber., 1911, 44,2767 ; A., i, 976 ; I<. H. Mcyer, ibid., 2729 ; A . , i, 865.I<. 11. Meyer, Annulen, 1911, 379, 37 ; A . , i, 194.39 K. H. Meyer and 1'. Kappelnieier, luc. citORGANIC CHEMISTRY. 105is obtained in the pure condition. I n suitable solvents an equili-brium between these substances may be established. A similarpair of isomerides having the constitution of anthraquinol (111)(111.) m. 1and hydroxyanthrone (IV) have also been obtained. The former isyielded by the interaction of anthraquinone with alkaline reducingagents, and the latter by warming bramoanthrone (V) with aqueous/\/-co-\/\\/\CHBrI A/ I I(V.)acetone.The velocity of interconversion of these isomerides is verysmall, but with catalytic agents such i ~ s alkali hydroxide it assumesa very high value, the equilibrium being greatly in favour of thedihydroxy-derivative. The isolation of these desmotropic pairsaffords some information on the question of tautomerism in thephenols. The assumption made by Thiele that the high reactivityof the phenols is due to change into the ketonic form seems to becontrsdicted by the behaviour of these compounds, for in the twopairs examined the phenolic derivative is the more reactiveisomeride.Polymerisation of Unsaturated Substances and SomePhotochemical Changes.I n view of the probability that polymerisation may take somepart in the natural synthesis of complex substances, it may be ofinterest to review the results of recent researches on this subject,especially since in some cases the effect in question has beenproduced by the aid of light.Considering the novelty of thesubject, the researches carried out during the past year have beenrelatively numerous, and it is obvious t o suggest that this suddengrowth is due to thg stimulus given by recent experiments on theformation of caoutchouc and similar substances.The polymerisation of unsaturated substances may be effectedby heat or by the influence of light, the ultra-violet rays beingparticularly efficient; but with either reagent the effect may bereversed.The temperature, and no doubt also the pressure, atwhich the condensation is carried out influences the characterof the products, although the nature of the latter does not depen106 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.on the period of heating. I n most cases a mixt,ure of complexsubstances is formed, and f o r obvious reasons attention has beenmainly directed to the simpler of these.It seems impossible in the present state of affairs to lay downany comprehensive rules governing the structure of the productsobtained from these intermolecular actions, but generally speakingi t may be said that cyclic compounds are produced. However,substances containing the open-chain structure have been occasion-ally observed ; for example, the ap-unsaturated ketone, methylene-acetone (I), on being heated42 yieIds the octenedione (11), whilstCH,:CFI*CO*CH, CU,* CO CH,*CH,*CH,* CO* CH:CH,(I.) (11.)CH,* CO*C'FI,.CH,*CR,*CO*CH,*CH,*OH(111.)if water and alkali carbonate are present the octadionol (111) isobbained.With ethylenic compounds, such as the derivatives of cinn-amylidene and of diallyl, i t appears that mild conditions of poly-merisation tend to produce four- and eight-membered cyclic systems,whilst more intense conditions yield substances containing the six-membered arrangement. To illustrate this rough generalisationthe following researches may be quoted. Numerous experimentshave shown that cinnamic 43 and do-cinnamic 44 acids are convertedby the influence of light into a- and B-truxillic acids which containthe four-membered ring; but i t has now been observed's thatprolonged heating of ethyl cinnamate yields the ester of the sixmembered polycinnamic acid :CO,Et* QH*CHPh*QH*CO,EtC,H,* CH* CHPh- CH C0,Et'Other researches have dealt with the action of light on cinn-amylidene compounds, with the uniform result that the cyclobutanederivative was obtained ; thus a-cyanocinnamylideneacetic acidyields the cyclic compound:CO,Et*C( CN) :CH*$?H*QH*C,H,C, H,*CH*CH* CH: C( CN) C0,Et 'whilst similar substances were furnished by cinnamylideneaceto-4a Farbenfabriken vorrn.F. Bayer & Go., D.R. -P. 227176,227177 ; A . , i, 102, 11 4.43 C. N. Riibcr, Ber., 1902, 35, 2908 ; A , 1902, i, 785 ; G.1,. Ciaiiiician and P.A4 A. W. K. de Jong, Proc. K. Akad. Wetem-ch. Amsterdam, 1911, 14, 100; A . ,45 C . Liebermanii ; t i i d M. Zsuffa, Bcr., 1911, 44, 841 ; A., i, 370.Silber, ibfrl., 1903, 46, 4 2 6 6 ; A . , 1904, i, 161.i, 639.31. Reiuier, Amw. Cheni. J., 1911, 45, 417 ; A . , i, 447ORGANIC CHEMISTRY. 107ph enone,47 cinnatmylidenemaldnic 48 and a-methylcinnamylideneaceticacids.49 The more violent conditions of polymerisation have notyet been applied to the latter group of compounds. The formationof cyclic compounds has also been observed in the polymerisationof ethylene under pressure a t high temperatures, which furnishes aproduct consisting chiefly of polymethylenes, accompanied byparaffins and more complex ethylenic hydrocarbons. Since indepen-dent experiment has est,ablished the fact that the cyclic arrange-ment is prone to decomposition under these conditions, it appearsprobable that the formation of these open-chain derivatives is duet a secondary decomposition of the parental polymethylenes.The question of the relation between the conditions of polymerisa-tion and the nature of the products has been more carefullystudied 51 with derivatives of divinyl which contain a, conjugatedsystem of ethylenic linkings.These substances yield mixtures of acyclohexene derivative and a resinous compound, which contains thecyczooctadiene system, divinyl, for example, giving ethenylcyclo-hexene (I) and the polymeric derivative of cyclooctadiene (11) :(1.) (11.1In this instance and those of isoprene and diisopropenyl it hasbeen found that the milder conditions, such as a relatively lowtemperature or under the influence of light, favour the productionof the eight-membered ring, whilst higher temperatures augmentthe quantity of the cydohexene derivative.From the numerousdata available it seems that the cyclobutane ring is not formedfrom substances containing a system of conjugated ethyleniclinking; but it may be remarked that Thiele's hypothesis addsweight to the supposition that this ring may be formed by intra-molecular condensation under conditions which have not yet beenrealised in experiment. It appears, moreover, that the cyclobutanesystem is easily formed from hydrocarbons of the peculiar allenetype, the condensation being as usual intermolecular.52 Experimentswith as-dimethylallene (I) yielded two isomeric derivatives of cyclo-bctane (I1 and 111), together with dipentene and other morecomplex substances :47 H.Stobbe and C. Riicker, Ber., 1911, 44, 869 ; A . , i, 385.C. X. Riiber, ibid., 1902, 35, 2411 ; A . , 1902, i, 617.A. L. Macleod, Amcr. Chenz. J., 1910, 44, 331 ; A4., 1910, i, 845.so W. N. Ipatieff, Ber., 1911, 44, 2978, 2987 ; i l . , i, 937.51 54. V. Lebedeff, J. Rms. Phys. C h c ? ~ SOC., 1910, 42, 949 ; A , , i, 26 ; set!52 S. V. I,ebedeff, ihid., 1911, 43, 820 ; d 4 . , i, 774.also D.R.-1'. 235686 ; A . , i, 1003108 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.CH,:C :CMe, QH,*Q:CMe, yH,-Q:CMe,(1.) (11.1 (111.)The polymerisation products containing the cyclowtadienearrangement exhibit physical and chemical properties which aresimilar t o those of the natural caoutchouc, and hence especialattention has been paid to the conditions that govern their forma-tion.The caoutchoucs derived from isoprene, divinyl, anddimethylbutadiene are best prepared by heating these hydrocarbonsin sealed vessels without the presence of a solvent at temperaturesnear l@Oo for several days,53 only slightly different conditions beingrequired in each case to obtain a masimum yield of the product.The caoutchoucs obtained by this method of polymerisation havebeen termed the '' normal C ~ O U ~ C ~ ~ U C S , ~ ~ for investigation of theirozonides shows that they are analogous with the natural product.However, the diozonides obtained from these synthetic caoutchoucsare not homogeneous, for they may be resolved into two isomeridesof different solubility, the more soluble being present only in smallamount.On being decomposed with water these isomerides yielddifferent products, which may be interpreted as indicating that theparental hydrocarbons differ from one another by the relativesituation of the ethylenic linkings in the octadiene complex ; forexample, since the less soluble ozonide obtained from isoprene-caoutchouc breaks down into lzvulaldehyde, the hydrocarbon maybe regarded as a derivative of the dimethylwtadiene shown in thefollowing formula (I), whilst the more soluble isomeride is probablyQH2*CH:CMe*yH, QH2*CH:CMe-RHC H;CMe: CH* CH,(1.1 (11.1CH,*C:CMe, CMe,*C:CH,CH,*CHMe*CH,*CHderived from some such system as that shown in forrnula (11), fori t yields methylglyoxal on treatment with water.The polymerisa-tion of these unsaturated hydrocarbons may be effected a t lowertemperatures by the influence of metallic sodium, but the products,although of similar physical character, do not exhibit the samechemical behaviour its the normal caoutchoucs. For the presenttheir nature remains undetermined.The production of isoprene and its congeners is of technicalimportance f n the preparation of a synthetic caoutchouc, and manyexperiments have been recently made on that question. Among themethods devised during the past year for the production of isoprene,that originating with acetnne deserves especial notice.With theaid of maglLesium ethyl bromide, acetone is converted into tert.-amyl53 C. D. Hairies, Annnleit, 1911, 383, 157 ; A., j, 798.54 C. D. Harries, loc. citORGANIC CHEMISTRY. 109alcohol (I), and thence into trimethylethylene (11). The dibromideof the latter (lII), when allowed slowly to drop on to hot soda-limeof suitable character, furnishes excellent yields of the requiredhydrocarbon. Another noteworthy method 55 consists in passingthe vapours of dipentene over a spiral of metallic wire which isheated with the electric current, whilst a patented method appliesthe process of exhaustive methylation to as-diaminobutane and itsderivative^.^^The study of the condensation of keten 57 and its derivatives 58has yielded further interesting data on the question of polymeris*tion.The extreme ease with which these substances polymeriseand depolymerise might give rise to the suspicion that thebimolecular compounds are merely physical aggregates of thesimpler molecules, but this is negatived by interaction with certainreagents which yield derivatives of the diketomethylene group,*CO*CH,*CO*CH,*, thus proving the presence of the cyclobutanonestructure.Many of the simpler ketens yield the cyclobutane derivativeswhen kept at the ordinary temperature; in the case of keten itselfthe polymerisation may proceed further to the six-membered systemof dehydracetic acid, but this does not appear t o take place soeasily with the substituted compounds.The ease with which thecyclobutane ring is broken by the aid of heat is remarkable, forsimple distillation of the polymeride renders an almost theoreticalyield of the keten. Use has been made of this tendency to depoly-merise in obtaining some derivatives of keten which only appearas polymerides in the usual methods of preparation. I n this mannerethyl ethylketencarboxylate has been isolated, but it can bepreserved only at low temperatures. With this substance thetemperatures of polymerisation and depolymerisation seem to lieclose together :CO,Et*CEt: CO - ---) CO,Et-yEt* 70CO:CEt*CO,Et CO-CEtoC0,Et.Taking into account the general behaviour of substances whichform cyclic carbon compounds on polymerisation, the general rulemight be framed that those cyclic systems which are formed more55 C.a. Harries and K. Gottlob, AnnuZen, 1911, 383, 228 ; A,, i, 798; H.Staudinger and H. W. Klever, Ber., 1911, 44, 2212 ; A., i, 731.MT D.R.-P. 231806.Miss F. Chick and N. T. M. Wilsmore, Tmns., 1910, 97, 1978.63 H. Staudinger, Ber., 1911, 4.4, 521; 1909, 42, 4903; A . , i, 306; 1910, i, 89110 ANNUAL REPORl'S ON THE PROGRESS OF CHEMISTRY.easily are the more prone to decompose. It seems, however, thatthis rule cannot be applied to all cyclic substances, for exceptionalcases are met with in other products formed from ketens by similarprocesses ; for example, ketones unite with certain ketens,59 giving6-lactones, which decompose on heating into these components orinto carbon dioxide and the ethylene derivative:With these substances ring-formation proceeds with difficulty, anddecomposition occurs easily.On the other hand, the B-lactam whichis easily formed from diphenylketen and benzophenoneanil60 :$?Ph2*70 CPh,:COCPh,*NPh, CPh,: NPh 7-Ais not very easily split into the components.I n addition to those performed with ethylenic derivatives, experi-ments have been made on the behaviour of other types of compoundsin the presence of light. The majority of the researches carriedout on these lines during the past year have dealt with the reactionsof ketones with various substances. I n these interactions it is raret o find a homogeneous product, for the reacting substancesfrequently undergo decomposition.However, it may be stated asa general rule that ketones yield a compound of the l 1 hydrol"type if a substance containing the available hydrogen is present :OH CR,:O + HR' = CR,<R, .The peculiarity of the influence of light on these interactionsis the unexpected activity which it confers on certain methylenegroups ; for example, those contained in ethers,B1 alcohols,62 esters,83and acids.64 'M.Tith ketones these substances yield the followingtypes of compounds :A similar class of product has been obtained from phenanthrene-59 H. Staudinger, Bcr., 1908, 41, 1365; A., 1908, i, 410; AsmaZen, 1911, 380,60 H. Staudinger, Ber., 1911, 4, 365 ; A . , i, 215.61 G. L. Cianiician and P. Silbcr, ibid., 1354; A , , i, 650.62 Ibid., 1280 ; A ., i, 513.G3 E. Pateriib and G. Forli-Forti, Gazzetta, 1910, 40, ii, 332 ; A., i, 66.6' E:. Patcrnb and G. Chieffi, ibid., 321 ; A., i, 65.243 ; A., i, 459ORGANIC CHEMISTRY. 111quinone and various aldehydes,Gs the interaction proceeding asfollows :I tI ~ @ & + CHO*Ph = y==cOH d*COPh'I n all these cwes subsidiary products are formed, which are ulti-mately due either to polymerisation or to decomposition of one ofthe reagents. I f ethers, alcohols, or esters are employed, consider-able reduction of the ketone is apt to take place, the phenomenonbeing undoubtedly due t o the nascent hydrogen which is formedwhen these substances are submitted66 to the influence of light.Some very interesting experiments have been made on the trans-formation of ethylenic isomerides by the influence of light.Fromthe numerous data now available it seems that the process may begenerally applied 67 to the preparation of the unstable isomerides oflow melting point from the more stable. In no case, however, isthe transformation complete, since an equilibrium is established ;in fact, there is no reason to doubt that the process is reversible,for with many pairs of isomerides the change has a t one time oranother been realised68 in both directions. So general does thisphotochemical process appear to be, that it has been recommendedas a means of deciding whether a pair of isomerides are stereo-chemically related. The application of the method to coumaricand coumarinic acids has resulted in favour of this relation betweenthe two series.Also, with oximes the conversion of syn- into anti-isomerides, and vice versa, has been observed.Some of these observations are of particular interest in theirbearing on the attractive hypothesis69 that the change of onestereoisomeride into the other takes place through the intermediatesynthesis of a tetramethylene derivative, which ultimately breaksdown in such a way as to yield the latter. One of the chief diffi-culties which stands in the way of this hypothesis has arisen fromthe circumstance that in the few cases in which the cyclic producthas been isolated this has been too stable to permit the assumptionof spontaneous decomposition. The objection is now somewhatweakened by the discovery of extremely unstable derivatives oftetramethylene, although it has not yet been shown that light caneffect the requisite depolymerisation.There is no doubt that a more intimate knowledge of the processes65 H.Klinger and W. Roerdansz, Annnlen, 1911, 382, 211 ; A . , i, 633.D. Berthelot and H. Gaudechon, Compt. re7zd.: 1911, 153, 383 ; A . , ii, 835.67 R. Stoermer, Ber., 1911, 44, 637 ; A . , i, 295 ; 1910, i, 114.68 For example, funiaric and maleic acids: G . L. Cianiician and P .Silber, ibid.,69 A. W. Stewart, Proc., 1905, 21, 73.1903, 36, 4266 ; A . , 1904, i, 161; R. Stoeriiicr, loc. cit112 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.which occur during these photochemical interactions can only beattained by quantitative experiment.Important researches of thistype have been carried out within a recent period.The photochemical transformation of maleic into fumaric acidi n presence of small quantities of bromine has been quantitativelystudied.70 One of the more important results of these experimentsis the proof that the reaction is unimolecular. Moreover, thevelocity of inversion seems independent of the temperature, andwhen equilibrium is attained the percentage of fumaric acid presentis approximately proportional t o the amount of bromine taken.Unlike some other photochemical interactions the conversion ofmaleic into fumaric acid does not continue after the stimulatingsource of light has been removed. This peculiar after-effect hasbeen observed in the photobromination of toluene, and the causehas now been revealed'l by a series of exhaustive experiments.These show that the after-effect is caused by the presence of atmo-spheric oxygen, which forms a catalyst, probably an oxide of bromine,by combination with the halogen present.Bromination of toluene in the side-chain may be accomplishedeven in the dark with the aid of this catalyst; in fact, if ozonisedair is passed into the unilluminated bromination mixture the inter-action is violent; thus ozone may be used with advantage as a" halogen carrier " for substitution in the side-chain of aromaticcompounds, and in this respect i t is unique.The quantitative studyof the photobromination of these substances has hitherto beenrendered impassible by the after-effect in question; but the disturb-ance may be eliminated by the addition of a very small amount ofiodine, which decomposes the unstable catalyst. Using this precau-tion, measurements were obtained which show that the interactionis unimolecular.Carbohydrates and Allied Substances.During the past year the chemistry of the aldoses has been con-siderably developed, but mainly along the lines laid down by thepioneers of this work.The chief difficiilty which stood in the wayof the expansion of research in this direction was the scarcity ofmaterials from which further syntheses might be started; but therecent discovcry of some of this material in natural products hasremoved the obstacle, and the opportunity has been seized; thus,of the sixteen possible methylpentoses, eight are now known, whilstthe group of hexoses has been almost completed by the discovery7O L.Bruner and M. Krdlikowski, Bull. Acad. Sci. Crmow, 1910,192 ; A . , i, 9.L. Bruner, S. Czamecki, and Z. Lahocifiski, ibid., 23, 516, 560 ; A., i, 242ORGANIC CHEMISTRY. 113of d-allose and d-altrose, only the lzevclisomerides of these sugarsbeing required to complete the group.Very interesting experiments have been performed on thesynthesis of carbohydrates from simple substances by means ofultra-violet light or sunlight ; for instance, an alkaline solution ofglycerol is found72 to contain a-acrose after being exposed to ultra-violet light in the presence of air; and the important observationhas been made73 that under the influence of these rays carbondioxide and hydrogen yield carbohydrates, but only when the latter-named reagent is in the nascent condition.An aqueous solution offormaldehyde, when subjected to the action of ultra-violet rays,furnishes 74 a volatile substance of reducing properties which appearsto be glycollaldehyde ; and other experiments 76 with formaldehydein the presence of oxalic acid lead ta the isolation of a crystallinereducing sugar, which resemblm sorbwe. The study of the reverseaspect of this question has shown that in aqueous solution carbo-hydrates are decomposed by ultra-violet light. The few experimentswhich have been made seem to show that with polysaccharides apreliminary hydrolysis takes place,76 the simpler sugars being thendegraded to various products.MethyZpentoses.-A very thorough investigation 77 of the hydrcllytic products obtained from the complex glucoaide convolvulin hasshown that this substance contains no less than three methyl-pentoses, namely, rhamnose, rhodeose, and isorhodeoss.Cautioushydrolysis of the glucoside with aqueous barium hydroxide yieldsconvolvulinic acid, a-methylbutyric acid, and purgic acid ; thefirst-named of these acids yields on further hydrolysis with mineralacid a mixture of rhamnose and rhodeose, whilst from the last-named isorhodeose is obtained.The configuration of rhodeose has been determined by oxidisingthe lactone of rhodeonic acid. Using nitric acid as the oxidisingyo,* f,'HO QH 0H*Y*OH H*Y*OH H-Y*OHOH*?." OH*$?*H H*V*OHOH-Y'H OH-7.H OH-q'HC0,H 7H.O" YH*OHCH3(11.1C*,I-Trihydroxyglutaric acid.(1.)72 H. Bierry and V. Henri, Compt. rend., 1911, 152, 535 ; A., i, 255.73 J. Stoklasa and W. Zdobnickj, Biochcm. Zeitsch., 1911, 30, 433 ; A., i, 178.74 R. Pribram and A. Franke, Ber., 1911, 44, 1035 ; A . , i, 420.75 G. Inghilleri, Zeitsch. phtyiol. Chem., 1911, 71, 105 ; A., i, 354.Compare L Massol, Compt. rend., 1911, 152, 902 ; A., i, 356 ; H. Bierry, V.Henri, and A. Ram, i b d , 1629 ; A., i, 524.77 E. VotoEek, Ber., 1910, 43, 476 ; A., 1910, i, 274.REP. -VOL. VIII 114 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.agent, Z-trihydroxyglutaric acid was obtained, whence i t is evidentthat the aldose must be represented by either of two alternativeconfigurations ; but since rhoddtol, the corresponding alcohol, is notattacked by the sorbose-bacterium, it appears that the former ofthese is correct.This deduction is confirmed by submitting thesugar t o the cyanohydrin reactim, and subsequently oxidising therhodeohexonic acids then obtained. It will be seen that if formula(I) were correct, mannosaccharic and saccharic acids would then beformed, whilst the latter alternative demands the production ofmucic and talomu'cic acids. Actually saccharic acid was isolated,and no trace of mucic acid could be detected in the oxidationproduct of the rhodeohexonic acids. It may also be observed thatthe rotatory power78 of rhdeonolactone is in harmony with thisconfiguration.isoRhodeose 79 is evidently the optical antipode of isorhamnose,for apart, from the fact that this is indicated by the physicalproperties of the sugar and its derivatives, chemical evidence leadsto the same conclusion.When oxidised with nitric mid, isorhodeosefurnishes the inactive trihydroxyxyloglutaric acid :78 C. S. Hudson, J. Amer. Chrn. SOC., 1911, 33, 405; A . , i, 355.79 E. VotoEek, Ber., 1911, M, 819; A., i, 354ORGANIC CHEMISTRY. 115Moreover, on converting iscrhodeonic acid into the epimeric 8oacid by heating with pyridine, and applying to the productFischer's series of reactions-reduction, addition of hydrocyanicacid, and re-oxidation-mucic acid is obtained. The bearing of thisfact on the configuration of isorhodeose is explained by theaccompanying formulz.The evidence in favour of this structure iscompleted by the fact that the methyltetrose, obtained by degrada-tion of isorhodeose, on being oxidised,*l yields E-tartaric acid.By heating rhodeonic acid with pyridine in aqueous solution theisomeric epirhodeonic acid has been obtained,@ and when thelactone of this acid was reduced in the usual manner a newmethylpentose, epirhodeose, was formed :F O P p 2 H YHOH*V*OH HO.7.H 0H-Y-H (p2HOH*Q*H 0H.C-H OH*$.H OH*V*H0H.Q.H OH+H OH*q*H 0H.Y.H$!H*OH $!H*OH $!"-OH OH*7'"C02HTrihydroxyribo - Rhodeonic acid. epiRhodeonic acid. epiR)hodeose.glntaric acid.This sugar has not yet been obtained in the crystalline state; itfurnished the same phenylosazone as that given by rhodeose, andon oxidation it was converted into trihydroxyriboglutaric acid,which, somewhat remarkably, was isolated as a weakly activelactone.Bexoses.--The discovery that d-ribose is a component of manynucleosides has led to the accumulation of a considerable quantityof this substance ; thus the preparation of the correspondinghexoses by the cyanohydrin process has come within the range ofexperiment.When d-ribose was submitted83 to this reaction, amixture of two hexonic acids was obtained, and these wereseparated by means of their calcium salts. The less soluble, whichwas named d-altrunic acid, must correspond with the configurationshown in the following scheme, for it gives talomucic acid onoxidation :CH* CH3 CH,8o It has been proposed (VotoEek, lac.cit.) to apply the term epimerism toexpress the relation between two aldoses which differ only in the configuration of thecarbon atom adjacent to the aldehyde grouping.E. Votoc'ek and C. Krauz, Ber., 1911, 44, 3287 ; A., 1912, i, 8.e2 E. VotoEek, ibid., 362 ; A . , i, 179.83 P. A. Levene and W. A. Jacobs, ibid., 1910, 43, 3141 ; A., i, 14.I 116 ANNIJAL REPORTS ON THE PROGRESS OF CHEMISTRY.H H H HOH*CH,* &-6--6--6*CO,H -+/+ 6H 6H i)H i>HFHO d-Allonic acid.H*q*OH H H H HH*$!*OH 6H 6H 6H i)HH*F*OH OH-CH,. 6--&-6---6c~0CH,*OH d- Allose.&Ribose. \ H H H O HO H ~ H , . & 6 - - ~ - - 6 0 ~ ~ , ~ -+6H 6H OH hd-Altronic acid./ Ic x \H H H O H FI H H OK6H 6H i)H HOH*CH,* &-6--&-bCHO CO,I-I* 6--&- &-6*CO,H6H 6 H 6H Hd-Altrose.d-Talomucic acid.hence the formula for the corresponding aldehyde, d-altrose. Theepimeric hexose, d-allose, is obtlaitled from the more solubled-allonic acid, which should yield allo-mucic acid on oxidation, but,the latter relation has not yet been verified by experiment. Thesynthesis of homologous aldoses from dextrose has been carried asfar as glucodec~se,~~ but there is nothing sufficiently remarkable inthis sugar or its relatives to warrant more than mention.A new line of research in this group has been opened by thestudy of aminomethylglucosides ; as yet the work has not proceededfar, but the preliminary results indicate that it will be of interest.An aminomethylglucoside has been prepared by two differentprocesses,85 which are indicated by the following schemes :Aminoglucose (from chitin) Met h ylglucosideI I + .+Aminotriacetyl bromogl ucose Bromotriacetylme thylglucosido! ! + J.Aminotriace tylmet h ylglucoside ( Aminotriacetylme t hylglucosid e)I I J.Amiiioniethylglucoside.J.Arninomethylgl ucosideThe products of these two methods are different, for that givenB4 L. H. Philippe, Compt. rend., 1910, 151, 956, 1366; 1911, 152, 1774; A . , i,85 E. Fischer and K. Zach, Ber., 1911, 441, 132 ; A., i, 117 ; J. C. Irvine, D.12, 112, 605.McNicoll, and A. Hynd, Tram., 1911, 99, 250ORGANIC CHEMISTRY. 117by the former may be hydrolysed to the ordinary glucosamine whichserved as the starting material, whilst that given by the latter yieldsa different aminoglucose.The precise relation between thesecompounds remains to be discovered.A new disaccharide, vicianose,86 has been obtained from theglucoside vicianin which occurs in the vetch. Since oxidation andsubsequent hydrolysis of the product yields gluconic acid andarabinose, the constitution of this sugar is probably :The production of synthetic glucosides has continued. In thesesyntheses advantage is taken of the reactivity of the halogen insub st a nces such as ace t ob r omoglucose and acet oc hlorogluc ose. Toobtain the glucosides of complex alcohols such as geraniol, cyclo-hexanol, and similar substances, it is sufficient to treata7 these inebhereal solution with the halogen derivative and silver oxide. Thesame method has led t o the production of glucosides derived fromthe phenolcarboxylic acids,88 the methyl esters being employed tomask the undesirable effect of the carboxyl group.The glucorjide solanine, (C2,H,,09N),,H,0, which is contained inSolanum sodomaeum, has been submitted to a thorough investiga-tion.89 When treated with hydrolytic agents i t furnishes galactose,a methylpentoae, and the base solanidine, C,,H3,0N.Little isyet known of the latter substance except that it contains hydroxyland the imino-group.Organic Compounds of Arsenic.Organic compounds of arsenic, although they have been knownfrom the middle of the eighteenth century,g0 did not attract muchattention until about four years ago; since that time, chieflythrough the circumstance that they are of extreme value in thetreatment of diseases of protozoal origin, their study has beeneagerly prosecuted.The new development of the chemistry of arsenic had its originin the discovery of Ehrlich and Bertheimgl that the compound,obtained in 1863 by B6cha,mpg2 by heating together aniline and86 G.Rertranci and G. Weisweiller, Compt. rend., 1910, 151, 884 ; A., i, 15.*7 E. Fischer and B. Helferich, Annalen, 1911, 383, 69 ; A . , i, 802.88 F. Mauthner, J. pr. Chem., 1911, [ii], 83, 556; A., i, 647.S9 G. Oddo atid M. Cesaris, Gazxetta, 1911, 41, 490, 534 ; A., i, 670, 671.9O Louis Claude Cadet-de-Gassicourt, Mem. Math. Phys. Acad. Roy., 1760,3, 635.91 P. Ehrlich and A. Bertheim, Ber., 1907, 40, 3292 ; A., 1907, i, 812.y2 11.A. RQohamp, Compt. rend. , 1863, 56, 1173118 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.arsenic acid and considered by him to be the anilide of arsenic acid,C,H,*NH*AsO(OH),, was in reality p-aminophenylarsinic acid ofthe structure :N H ,/-\AsO(OH), . \-/The proof that this co'mpound, the sodium salt of which hadcome into extensive therapeutic use under the name " atoxyl," wasnot a chemically indifferent anilide, but a stable amino-derivativecapable of taking part in the many reactions associated with suchcompounds, opened a wide field for investigation.As a result of the work of the last four years an immense numberof compounds containing arsenic similarly attached to variousaromatic residues has been prepared, these again serving as startingpoints for the elaboration of new substances varying enormously intoxicity and applicability as curative agents.Arsinic acids can be obtained from many aromatic amines andphenols having an unsubstituted para- or ortho-position by heatingthem with arsenic acid to a temperature approaching 200°, whenwater is eliminated, thus : 7 Or OHNH, or OH\I + AsO(OH), = H,O + /\I I v AsO( OH)2NH, or OH NH, or OHArylamines with a free para-position relative to the amino-groupyield p-arsinic acids ; thus,93 aniline, o-toluidine, m-toluidine,o-chloroaniline, p-xylidine, a-naphthylamine, and phenol yieldrespectively :p-Aminophenyl- 2-Aminotolyl- 5-Aminotolyl- 3-Chloro-4-amino-arsinic acid. 6-arsinic acid.2-arsinic acid. phenylarsinic acid.( Arsanilic acid.)93 p. Ehrlich and A. Bertheim, Ber., 1907, 40, 3292 ; A . , 1907, i, 812 ; 0. Adlerand R . Adler, ibid., 1908, 41, 931; A., 1908, i, 492; L. Benda and R. Kahn,ibid., 1672 ; A., 1908, i, 591 ; D.R.-P. 205616 ; A . , 1909, i, 279ORGANIC CHEMISTRY. 119NH, NH, OH&SO( OH),5- Amino-p-xylene-2-arsinic acid.\/\/AsO(OH),4- Aminonaphthyl-arsinic acid./\I 1\/AsO( 0 H )2p-Hy droxyp henyl-arsinic acid.Arylamines substituted in the para-position 94 relatively to theamino-group react similarly with arsenic acid, yielding aminoaryl-o-arsinic acids, but the, yields are generally poor; for example,p-toluidine, rn-xylidine, and p-chloroaniline yield :NH2 NH2 NH2/\AsO(OH), CH, /\ ,AsO(OH), ~ ) A ~ o ( o H ) ,\ \/ \/U1 CH34-Amino-m-xylene- 5-Chloro-2-aminophenyl-' i CH34-Aminotolyl-3-arsitiicacid.5-arsinic acid. arsinic acid,An important exception, however, is found in the case of p-nitro-aniline, which is relatively easily attacked,95 giving :N O,/-\N H,5-Nitro-2-aminophenylarsinic acid.Arsenic acid frequently oxidises arylamines, as in the well knownpreparation of magenta; the most advantageous methods ofprocedure have therefore been carefully worked out.The action between an arylamine and arsenic acid at 170-200°does not stop a t the formation of a monoarylarsinic acid, butproceeds if sufficient arylamine is present, and the heating is pro-tracted to the formation of a diarylarsinic acid,96 R,As*O-OH ; thusaniline yields di-p-aminophenylarsinic acid, and o-toluidine,di-2-aminotolyl-5-arsinic acid.97In this procezs, as in the alkylation, nitration, sulphonation, andhalogenation of arylamines, addition of the substituting agent tothe amino-group of the base undoubtedly first takes place, followedprobably by elimination of water and intramolecular rearrange-ment; for example, in the interaction of arsenic acid and anilinewe have:\-/AsO(OH),NJ32 NH,*OAsO(OH), NH*AsO(OH), NH,/\ /\ /\ /\I l - + I I -+ I I + I I\,/ \/ \/ \/AsO(OH),g4 L.Benda, Ber., 1909, 42, 3619; A., 1910,!i, 148.95 L. Benda, ibid., 1911, a, 3293; A., 1912, i, 61.96 L. Benda, ibid., 1908, 41, 2367 ; A., 1908, i, 747.97 See also F. L. Pyman and W. C. Reynolds, Tram., 1908, 93, 1180 ; L. Bendaand R.Kahn, Ber., 1908,41, 1672 ; A . , 1908, i, 591120 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the further interaction of the arsinic acid and aniline beingrepresented as :N H,*OAsO( C,H ,*NH,)* OH NH. AsO( C,,H,*NH,) *OH NH/\I I\//\ -+ I I -+/\ 0 \/ I N H 2.C6H4*A bO*OHMixed diaminodiarylarsinic acids can be similarly prepared byheating an arsinic acid with a base containing a different arylgroup.The aminic hydrogen atom of arsinic acids can be replaced byalkyl or similar groups ; for example, p-dimethylaminophenylarsinicacid, NMe2*C6H,*AsO( OH),,gs is obtained by the action of methylsulphate on an alkaline solution of sodium p-a,minophenylarsinate,whilst phenylglycine-p-arsinic acid,Q9CO,R*CH,*NH-C,H,*AsO( OH),,is obtained by heating for some hours a solution of the latter saltwith chloroacetic acid or by hydrolysing with alkali the nitrile,CN*CH~-NH*C,H,*AsO(OH),, produced by heating together inaqueous solution paminophenylarsinic acid, sodium cyanide, andformaldehyde.Phenylglycine-parsinic acid is of therapeutic valueon account of its slight toxicity.The aminic hydrogen atom can also be easily replaced by acylgroups 1 by ordinary methods ; p-acetylaminophenylarsinic acid(arsacetin), obtained by allowing acetic anhydride to react withp-aminophenylarsinic acid or its sodium salt, and the oxalylderivative, CO,H CO*NH*C6R,*As0 (OH),, prepared by heatingeither of the last two substances with oxalic acid,2 are of considerableimportance.The introduction of an acetyl group diminishes the toxic effectof the compound, whilst the presence of the oxalyl group confersgreater stability, and allows the compound to be used for thepreparation of various substitution derivatives.Carbamides 3 of the general formulaNRR'.CO*NH*C6H,*As0(OH),,where R and R' may be either hydrogen or an alkyl or aryl group,are yielded by the interaction of paminophenylarsinic acid withcyanic acid or its esters. Other arylarsinic acids behave similarly.g* A.Michaelis, Ber., 1908, 41, 1514 ; A., 1908, i, 590.~9 D.R.-P. 204664 ; A., 1909, i, 280.P. Ehrlich and A. Bertheim, Ber., 1907, 40, 3296 ; A . , 1907, i, 812 ; D.R.-PA. Bertheim, Ber., 1911, 44, 3092 ; A., i, 1055 ; D.R -P. 231969 ; A , i. 594.D.R.-P. 213165 ; A ., 1910, i, 148.191548 ; A., 1908, i, 591ORGANIC CHEMISTRY. 121Acyl derivatives of the methyl homologues of the arylarsinicacids are easily oxidised by potassium permanganate in alkalinesolution into the mrresponding carboxyarsinic acids ; fpr example,2-acetylamino~lyl-5-arsinic acid and 3-acetylaminotolyl-6-arsinicacid yield:NHAc NHAc/\and !,/CO,Hf\CO,HAsO( OH),\/AsO( OH),4-Acetylamino-3-carboxyphenyl- 4-Acetylaniino-2-carboxyphenyl-arsinic acid. arsinic acid.respectively.4By the action of hydrogen sulphide on the arsinic acids andtheir derivatives, the oxygen and hydroxyl groups are replaced bysulphur, with the formation of compounds of the general fformulz 6 :All the amino- and diamino-arsinic acids are easily diazotised,6the diazonium salts produced being able to take part in all thereactions characteristic of these compounds ; for example, whenheated with water they yield the corresponding hydroxy-compounds ;thus, p-h ydr oxyp hen ylarsinic acid, H O*C,H, As0 (0 H)2, 2-h ydroxy-tolyl-5-arsinic acid, HO*C,H,-AsO(OH),, 4-hydroxy-3-carboxyphenyl-arsinic acid (salicylarsinic acid), and 4 : 4’-dihydroxydiphenyl-arsinic acid (HO*C,H,),hO*OH, are obtained from paminophenyl-arsinic acid, 2-aminotolyl-5-arsinic acid, 4-amino-3-carboxyphenyl-arsinic a i d , and 4 : 4/-diamindiphenylarsinic acid respectively.The diamtised arsinic acids couple with various amines andphenols.I n all the axsinic acids and their derivatives the arsenic is inthe quinquevalent condition. As, however, compounds in whichit is in the more active tervalent condition have an enormouslygreater toxic effect on trypanmomes, many reduction products ofthe former have been prepared of the types R-AsO,R-AsOH-AsOH-R,‘ 0.Adler and It. Adler, Ber., 1908, 41, 931 ; A . , 1908, i, 492 ; R. Kahn and1,. Benda, ibid., 3859 ; A., 1909, i, 75. ‘ D.R.-P. 205617.R. Kahn and L. Bends, Ber., 1908, 41, 3859 ; A., 1909, i, 75 ; 0. Adler and It.Adler, ibid., 931 ; A., 1908, i, 492 : TA. Renda, ibid., 2367 ; A., 1908, i, 742 : M.Barrowcliff. F. L. Pyman, arid F. G. P. Remfry, Trun.?., 1908, 93, 1593122 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.and R*As:AsR. Reduction of an arsinic acid to one or other ofthese stages can be effected by employing a reducing agent ofappropriate strength.Among those7 which have been often used in the reduction ofaminoarylarsinic compounds are sodium amalgam in methyl alcohol,stannous chloride in concentrated hydrochloric acid, sometimes witha little hydriodic acid as catalyst, sulphur dioxide in the presence ofa little hydriodic acid as catalyst, and, lastly, sodium hyposulphite.Reduction of an arsinic acid to an arsenoccompound can becarried out in one operation, or an arsenious oxide may be isolatedas an intermediate product.Direct reduction appears simple, butat times yields a less pure product than when it is carried out intwo stages. Speaking generally, reducing agents act less readilyon compounds containing quinquevalent than on compoundscontaining tervalent arsenic.I n preparing the arylarsenious oxides, sulphur dioxide in presenceof a little hydriodic acid is very advantageously employed.Sulphurdioxide itself acts very slowly on arsinic acids, whilst the action ofhydriodic acid is reversible ; thus, for example :NH,*C,H,*ASO(OH)~ + 2HI NH,*C,H,*AsO + 2H,O + I,.The arylarsinic acids are therefore best reduced to the aryl-arsenious oxides by dissolving their sodium salts in water, addinga little potassium iodide, and passing sulphur dioxide for somehours. On aading ammonia, the arsenious oxides separate, usuallyas white, crystalline solids.p-Aminophenylarsenious oxide, NH2*C6H,*As0, p-hydroxyphenyl-arsenious oxide! HO*C,H,*AsO, 2-aminotolyl-5-arsenious oxide?NH2-C7H,-As0, and 3-amino-4-hgdroxyphenylarsenious oxide,loNH,*C,H,(OH)*AsO, are thus obtained from the correspondingarsinic acids.In paminophenylarsenious oxide the linking between arsenic andcarbon is very much looser than in arsinic acids, and when theoxide is heated with dilute hydrochloric acid, it is oonverted intoarsenious oxide and triaminotriphenylarsine 11 :3NH,*C,H,*AsO = (NH2*C6H4)3As + AqO,.This latter forms it well crpstallised triacetyl derivative, which,when dissolved in dilute acetic acid containing excess of sodiumacetate, is converted by the action of iodine into triacetylamino-7 P.Ehdich and A. Bertheim, Ber., 1910, 43, 917 ; A., 1910, i, 451 ; ibid., 1911,44, 1260; A , , i, 593.8 D.R.-P. 213594; A . , 1910, i, 148.9 D.R.-P.212205 ; A . , 1910, i, 84.lo D.R.-P. 235391 : A . , i, 1055.l1 P. Ehrlich and A. Rertheim, Ber., 1910, 43, 923 ; -4., 1910, i, 451ORGANIC CHEMISTRY. 123triphenylarsinic oxide, (CR3*CO*NH*C,H&AsO, a compound pre-viously obtained by acetylating triaminotriphenylarsine oxide,l2(NH,*C,H,)3As0, obtained by the prolonged interaction of arseniouschloride and aniline in boiling toluene, and subsequent decompmi-tion of the condensation product by boiling aqueous sodiumcar b onat e .p-Aminophenylarsenious oxide dissolved in sodium hydroxidereacts with cliloroacetic acid,13 forming p-aminophenylarsenoaceticacid, NH,~C,H,*As(OH)O*CHz*CO,H. The halogen alkyls reactsimilarly, giving a notable extension of G. Meyer’s method ofpreparing primary arsinic acids from sodium arsenate and halogenalkyl.The aminoarylarsenious oxides are converted by the action ofstrong solutions of the halogen hydrides into salts of the correspond-ing arsine dihalides ; for example, p-aminophenylarsine oxideyields wit’h concentrated hydrochloric acid the hydrochloride ofp-aminophenylarsine dichloride, ~ NHz*C,H,*AsCl,,HC1, and corre-sponding compounds with liydrobromic and hydriodic acids.14When paminophenylarsinic acid is similarly heated with fuminghydriodic acid the hydriodide of p-aminoarsine tetraiodide,NH,-C,H,-AsI,,HI, is formed.l54 : 4/-Diaminodihydroxyarsenobenzene,l6 the compound intermedi-ate between paminoarsenious oxide and 4 : 4’-diaminoarseno-benzene :NH,. C6H4*As0 4 N H,*C, H,.AS( OH)* AS( 0 H)*C,H, NH, -+NH,*CGH,*As:As*C,H4*NH~,has been obtained by reducing the former, dissolved in methylalcohol, with sodium amalgam.Sodium hyposulphite l 7 is anespecially useful reducing agent for converting t’he arsinic acids orarsenions oxides into arseno-campounds. It is generally employedin presence of alkali and magnesium chloride, the latter being foundto diminish the formation of by-products in such reductions.The arsinic acid is generally digested with a slightly warmedsolution of sodium hyposulp hite containing sodium hydronide andmagnesium chloride. Sodium p-aminophenylarsinaDe when thusreduced yields 4 : 4/-diaminoarsenobenzene, and sodium p-hydroxy-phenylarsinate yields 4 : 4/-dihydroxyarsenobenzene 18 :l2 G. IT. Morgan and Miss F.M. G. Micklethwait, Trans., 1909, 95, 1473.Is W. M. Dehn andS. J. McGrath, J. Amer. Chem. Xoc., 1906,28,347 ; A . , 1906,l4 A. Bertheim, Ber., 1911, M, 1070 : A . , i, 593.l5 A. Patta and P. Caccia, Roll. SOC. Ned. Chiriwg. Pavia, 1911 ; A , , i, 1554.l6 D.R.-P. 206057; A., 1909, i, 347.17 P. Ehrlich and A. Bertheim, Ber., 1911, 44, 1265 ; A., i, 593.-18 D.R -P. 206456 ; A , 1909, i, 347 ; ibid., 213594 ; A . , 1910, i, 148.i, 341124 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.NH, or OH NH,or OH NH, or OHA\ /\ /\Arseno-o-cresol, AS~(C,H,M~*OH)~, is similarly prepared from2-hydroxytolyl-5-arsinic acid, whilst tetrachlorcl, tetrabromo-, andtetraiodo-arsenophenols are obtained from the correspondinghalogenated derivatives of p-hydroxyphenylarsinic acid.19All amino- or hydroxy-phenylarsinic acids and their substitutionproducts yield their corresponding arsenwxmpounds.These arsen orcompminds can neither be distilled nor crystallised,and many possess colloidal properties.Even in the solid state theyoxidise in the air, and to be kept unchanged mlnst be sealed in tubesexhausted or filled with some indifferent gas.Arsenophenylglycine,zO As,(C6H4*NH*CH2*C~,H),, prepared byreducing phenylglycinearsinic acid, C02H*CH,*NH*C,H4*AsO(OH)z7on account of its low toxicity has been extensively employed inmedicine.21pArseno-o-tolylglycine 22 is similarly obtained from o-tolylglycine-5-arsinic acid :NH*CH,*CO,H CO,H*CH,*NH NH*CH,*CO,H/\ /\CH--+As=As\/AsO(OH),\/ \/' CH3J I I 1 3Phenylglycol-p-arsinic acid, ~~,H°C'R,oO~C6H4~AsO(OH)e, pre-pared by heating p-hydroxyphenylarsiic acid dissolved in aqueousalkali with chloroacetic acid, yields, when thus reduced, a r ~ e n c ~mandelic acid,,3 As,(C,R,*O*C'H,*CO,R),, a compound pwsessingpowerful trypanocidal properties.The arsenic acid residue, *AsO(OH),, which is so firmly attachedto the ring in arsinic acids that it is not affected in most reactionsin which these compounds take part, is easily removed by halogens;thus an aqueous solution of p-aminophenylarsinic acid gives analmost quantitative yield of s-tribromoaniline when mixed withbromine water.By very careful halogenation, however, Bertheimhas succeeded in preparing mono- and di-halogen aminoarylarsinicacids of the types :l9 D.R.-P.235430 ; A . , i, 1055.2o D.R.-P. 206057; A . , 1909, i, 347.P. Ehrlich, Ber., 1909, 42, 36.22 D.R.-P 212205; A . , 1910, i, 84.23 D.R.-P. 216270 ; A . , 1910, i, 452.24 A. Eertheim, Brr., 1910, 43, $29 : A , , 1910, i, 346ORGANIC CHEMISTRY. 125By careful treatment the hydroxyarylarsinic acids can be simi-larly substituted ; for example, sodium phydroxyphenylarsinategives with sodium hypochlorite or hypobromite the dihalogenatedacid.25The nitration of the arsinic acids has led t o results of greatimportance.Neither p-minophenylarsinic acid nor its acetyl derivative canbe nitrated without considerable decompmition. One nitregroupis, however, easily introduced if oxalyl-p-aminophenylarsinic acid,0O2H0CO*NH*C6H,*As0(013[)2, is cautiously nitrated with amixture of nitric and sulphuric acids.26 On hydrolysis, 3-nitro-4-aminophenylarsinic acid, NH,*C,H3(N0,)*AsO(OH)2, is obtained.The urethane, C0,Et*NH.~6H,oAso(OH)~, obtained by the actionof ethyl chlorocarbonate on p-aminophenylarsinic acid, can be usedin place of the oxalyl derivative.273-Nitrcl4-aminophenylarsinic acid has also been obtained byheating together arsenic acid and o-nitroaniline.28When the sodium salt of 3-nitroc4-aminophenylarsinic acid iscautiously reduced by the calculated amount of sodium hypwulphite,3 : 4-diaminophenylarsinic acid, C,H,(NH,),*ASO(OH)~, is pro-duced.29 This behaves as a typical orthodiamine, and forms anazimino-compound (I) with nitrous acid, a quinoxaline (11) withphenanthraquinone, and a cyclic carbamide (111) with carbonylchloride, thus :2526272829(111.)D.R.-P.235430; A., i, 1055.A. Bertheim, Ber., 1911, M, 3092; A., i, 1155; D.R.-P. 231969.D. R.-Y. 232879.E. Mameli, Boll. China. Purm., 1909, 48, 682 ; A., 1909, i, 980.A. Bertheim, Ber., 1911, M, 3092; A., i, 1055126 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.It is converted by energetic reduction into tetra-aminoarseno-benzene :It is noteworthy 30 that when 3-nitr0-4-aminophenylarsinic acidis heated to about 80° with a solution of potassium hydroxide, theamino-group is replaced by hydroxyl, ammonia being evolved, and3-nitre4-hydroxyphenylarsinic acid produced :NH2 OH{)NO2 -+ ()No2\/A sO(OH),\/AsO(OH),5-Nitro-2-aminophenylarsinic acid 31 and 3-nitr~2-aminotolyl-5-arsinic acid behave similarly.The therapeutically active hydroxyarylarsinic acids obtainedeither directly from the phenols or indirectly32 through the amino-arylarsinic acids can be nitrated more easily than the correspondingamino-compounds.Direct nitration of phydroxyphenylarsinic acid by a mixture ofnitric and sulphuric acids yields either the mono- or di-nitrecompound,33 according to the amount of nitric acid used and thetemperature a t which the operation is conducted :0 H OH OHWhen reduced by means of gentle reducing agents t'hese yield thecorresponding aminohydroxyphenylarsinic acids, whilst more vigor-ous reduction leads to the formation of arseno-derivatives.When 34 3-nitre4-hydroxyphenylarsinic acid is reduced by digest-ing its sodium salt dissolved in sodium hydroxide with excess ofsodium hyposulphite in the presence of magnesium chloride, it yields3 : 3I-diamin~4 : 4/-dihydroxyarsenobenzene :OH OH OH30 D.R.-P.235141; A., i, 1056.3 l L. Benda, Ber., 1911, 441, 9293 ; A., 1912, i, 61.32 L. Renda, ibid., 3449; A., 1912, i, 64.33 L. I3enda and A. Bertheim, ibid., 3445 ; A . , 1912,34 D.R.-1'. 224953 ; A., 1910, i, 803.63ORGANIC CHEMISTRY. 127The dihydrochloridel of this base is the much-discussed compound‘‘ salvarsan.”5-Nitre2-hydroxyphenylarsinic acid, prepared from the amino-acid obtained from p-nitroaniline, behaves in a similar way to itsisomeride.35 When nitrated it yields a dinitrederivative :and when strongly reduced, as, for example, by sodium hypoeulphite,5 : 5’-diamine2 : 2’-dihydroxyarsenobenzene is formed :/’)NO, /)NH2 /\NH2Hol 1 .\/ -+ HOI Hob AsO(OH), \/----- As---- AsThe dihydrochloride of this base is isomeric with salvarsan.Different nitroaminophenylarsinic acids, in which the nitregroupis in the meta-position relatively t o the arsinic wid residue, arefurnished by the nitration of oxalyl-p-aminoarsinic acid, and alsofrom p-nitroaniline; from either of these, by diazotisation andreplacement of the diazoniurn group by hydrogen, m-nitrophenyl-arsinic acid can be obtained. This when dissolved in methyl alcoholand reduced by sodium amalgam gives m-aminophenylarsinicacid 36 :NH-CO*CO,H NH, 1I /\ I --+- ( y o 2 \\/ ‘q AsO(OH), AsO(OH),AsO(OH), /\\/AsO( OH),N J 3 2 7Y2 I I --+ /)AsO( I OH),\/NO,5-Nii;ro-2-rninophenylarsinic acid when reduced in alkalinesolution by ferrous oxide yields 2 : 5-diaminophenylarsinic acid 3’ ;this, however, by diazotisation and replacement of the diazoniumgroup by hydrogen yields only the m-aminophenylarsinic acid, andnot, as might have been expected, the isomeric orthecompound.Further, 5-nitro-2-acetylaminophenylarsinic acid is so unstablethat i t cannot be reduced without hydrolysis occurring; the oxalyl35 L.Benda, Ber., 1911, 44, 3293 ; A., 1912, i, 61.36 A. Rertheim and L. Benda, ibid., 3297 ; A . , 1912, i, 62.L. Benda, ibid., 3300; A., 1912, i, 62128 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.derivative, however, obtained by heating the sodium salt of the acidwith oxalic acid to 175O, is more stable, and can be reduced to thecorresponding amino-compound by means of iron powder and diluteacetic acid.This on diazotisation and replacement of the diazoniumgroup by hydrogen yields an oxalyl derivative, from which o-amino-phenylarsinic acid is obtained by hydrolysis 38 :NH--GO-CO--N HNH-CO-CO--NHThe three possible aminophenylarsinic acids being now known, itwas possible t o identify the amino-acidS9 yielded on reduction ofthe acid obtained in the direct nitration of phenylarsinic acid.40This proved to be identical with m-aminophenylarsinic acid ; conse-quently the nitro-acid has the meta-configuration, and the arsinicacid residue belongs to the group of mbstituents, including theanalogous groups NO, and 80313, which direct other enteringgroups into the meta-position.3-Nitro-4-arninoph'enylarsinic acid on diazotisation yields adiazonium salt, which when heated for some time to 18O in diluteacid solution containing an excess of sodium acetate exchanges itsnitro-group for hydroxyl, giving a new diazonium salt, and thisin alkaline solution couples with P-naphthol.The colouring matterproduced yields on reduction either 4-amino-3-hydroxyphenyl-arsinic acid or 4 : 41-diamino-3 : 3/-dihydroxyarsenobenzene, accordingto conditions.The former of these when reduced by sulphurous acid and a littlehydriodic acid yields 4-amin~3-hydroxyphenylaraenious oxide,which itself can be further reduced to the arsenMompound *l:38 L.Benda, Ber., 1911, 44, 3304; A., 1912, i, 63.39 D.R.-P. 206344 ; A., 1909, i, 448.4O A. Michaelis, Ber., 1894, 27, 263 ; A . , 1894, i, 187 ; Annale78, 1902, 320,41 L. Eciida, (bid., 1911, 49, 3578.294ORGANIC CHEMISTRY. 129N2X N2X NH2( y o 2 -+ /)OH --t ()OH -+\/As0 (OH),\/AsO(OH),\/AsO( OH),--+The dihydrochloride of 4 : 4/-diamino-3 : 3'-dihydroxyarsenobenzeneis a third isomeride of salvarsan.Organic Compounds of Antimony.An interesting point has arisen in connexion with the preparstion of phenylstibine dichloride, C,H,-SbCl,. This was first obtainedby Hasenbaumer 42 by heating triphenylstibine with antimonytrichloride in xylene at 240O. In a recent communication Michaelisand Giinther43 state that they always obtain in this reactiondiphenylstibine chloride, (C6H,),SbC1.Both these observationsprove to be correct, the experiments of Morgan and Miss Mickleth-wait44 showing that the action is a balanced one in the senseindicated by the equations:2(C6H5),sb + SbC1, 3(C,H5),SbCL(C6H5),SbCl+ SbC1, 2C6H5*SbC12Diphenylstibine chloride when digested with aqueous sodium-carbonate yields diphenylstibine oxide, which when acted on byhydrogen sulphide gives the corresponding sulphide. It alsocombines with chlorine, forming diphenylstibine trichloride, whichis decomposed by hot alkalis, giving a solution from which dilutesulphuric acid precipitates diphmylstibinic acid :When treated with alcoholic silver nitrate, triphenylstibinedichloride is converted into triphenylstibine nitrate.45 This, how-ever, is not stable, and is converted by partial hydrolysis intotriphenylstibine hydroxynitrate, which may be recrystallised fromhot water without further change :(CgH5),SbCl, -+ (C,H,),Sb(NOs), -+(C6H,)sSb(OH)*N03.42 J.Hasenbaumer, Ber., 1898, 31, 2910 ; A . , 1899, i, 209.4a A. Michaelis and A. Gunther, ibid., 1911, %, 2316; A., i, 1056.44 G. T. Morgan and Miss P. M. G. Micklethwait, Trans., 1911, 99, 2283.46 G. T. Morgan and Miss F. M. G. Micklethwait, ibid., 1910, 97, 35.REP.--VOL. VIII 130 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Morgan and Miss Micklethwait 46 also find that phenylstibinicacid, diphenylstibinic acid, and triphenylstibine hydroxynitrate,when nitrated with a mixture of concentrated nitric and sulphuricacids, yield nitro-derivatives :/-\Sb6(OH), \-/N(-),m-Nitrophenylstibiuicacid. stibiuic acid.stibinic acid47one nitregroup entering each benzene nucleus in a meta-positionwith respect to the antimonic substituent.The presence of quinquevalent antimony in the benzene ring thusinfluences the introduction of a second group in accordance withthe met a-law of substitution.By reducing tri-m-nitrotriphenylstibinic acid, dissolved in boilingalcohol, by means of zinc dust and ammonium chloride, tri-m-amino-triphenylstibine, Sb(C6Ha*NH2)3, has been obtained.46 It forms acrystalline hydrochloride, Sb(C6H4*NH2,HC1),.Organic Cornpmnds of Sulphur.The readiness with which sulphur passes from the lower to thehigher states of valency and the reactivity with which i t is endowedwhen in the bi- and quadri-valent conditions give rise to manyreactions of peculiar interest in carbon compounds which containthis element.Although most of the chief types of these substanceswere known before 1870, very little attention was given to thestudy of their reactivity during the development of modern organicchemistry. It seems, however, from the continually increasingnumber of chemists working with these compounds that interestin this field of work is being somewhat revived, and there is nodoubt that thm0 who take up the investigation will find manyproblems of interest awaiting solution. Since i t would be out ofplace here to discuss these questions, attention may be at oncedirected to the work of the past year.When sulphur in organiccompounds is progressively saturated with oxygen, the stabilityof the complex continually rises until a maximum is reached insubstances mch as the sulphones, which contain this element in thesexavalent state. In the lower stages of oxidation the atability ofthe group is very much less, and it is not surprising that effortsto isolate the sulphoxylic acids, R-SOH, have not yet met withsuccess. Hitherto the fleeting existence of these substances hasbeen deduced, although not always with certainty, from the*6 G. T. Morgan and Miss F. M. G. Micklethwait, Trans., 1911, 99, 2288.47 P. May, ibid., 1910, 97, 1958ORGANIC CHEMISTRY. 131behaviour of certain unstable compounds of bi- and quadri-valentsulphur; but recently substances have been isolated which areevidently closely related to these acids.Hitherto the secalledperchloromethylmercaptan, CCl,*SCl, which may be regarded asthe chloride of the sulphoxylic mid, has been the only represent*tive of its class; but it has been shown 48 that a new series ofaromatic derivatives may be obtained by the interaction of chlorineand suitable disulphides ; for example :NO2*C,H~*S*S*C,H,.NO~ + C1, = 2N02*C6H,*SCl.As might be anticipated, the halogen in these substances may beeasily replaced by other groups, and it seems within the bounds ofprobability that by choosing a suitable condition of the benzenenucleus a relatively stable sulphoxylic acid might be isolated fromthem.Clear proof of the existence of the sulphoxylic acida has beenobtained 49 from the hydrolysis of the disulphides with concentratedsulphuric acid.It has. long been known that the mercaptans areconverted by oxidation with this reagent into the disulphides. Thefirst stage in this interaction is the oxidation of part of themercaptan to the sulphoxylic acid :ArSH + 0 = ArS*OH,the latter then reacting with excess of mercaptan, forming thedisulphide :It is also made evident that this interaction is reversible, althoughin most cases the equilibrium is greatly in favour of the disulphide;but by removing the sulphoxylic acid the balance may be upset, andhydrolysis of the disulphide rendered complete. Removal of thesulphoxylic acid may be effected by raising the temperature of thesolution or by adding some reactive aromatic compound to themixture.In the former case the previously observed synthesis ofo-thianthrens Go or of their para-isomerides 51 is obtained by inter-molecular condensation of the sulphoxylic acid :ArS*OH + ArSH Ai S-SAr + H,O.whilst in the latter case unsymmetrical monoeulphides are formed :ArS-Oa+ HAr'= ArSArt+ H20.The last-named prcxess may be applied to the synthesis ofderivatives of thioxanthone.6248 T. Zincke, Ber., 1911, 44, 769; d., i, 368.48 W. G. Prescott and S. Smiles, Tram., 1911, 99, 640.50 K. Fries and W. Volk, Ber., 1909, 42, 1170; A., 1909, i, 406.51 T. P. Hilditch, Trans., 1910, 97, '2579.52 Miss E. c f .Marsden and 8. Smiles, ibid., 1911, 99, 1353.K 132 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.A similar decompaition has been observed with the disulph-oxides,a which yield the sulphinic and sulphoxylic acids as follows :H,O + ArSO-SOAr =ArS-OH + ArS02H.If the hydrolytic mixture is heated, thianthren formation maytake place:but if reactive substances such as phenetole are present, the sulphinicacid is converted into the sulphonium salt (l), whilst the sulphoxylicacid yields the monosulphide (2):(1) ArS0,B + 2Ar’H =ArAr’,S*OH> + H,O.(2) ArS-OH + Ar’H =ArSAr’ + H,O.However, it may be observed that the course taken by these inter-actions depends to a great extent on the constitution of the reagents.The study of the additive products formed by hydrogen per-sulphide with organic compounds has led to results of generalinterest.This reagent, like others which contain the sulphydricgrouping, yields additive compounds with aromatic aldehydest4that furnished with benzddehyde being (I) :O H HO H292 s*s(1.) (11.1C6H.5. CH<S s>CH’ CcH5 -+ C,H5* CH<S.S>CH’ C,H,The isolation of these substances has led to a method of preparingthe carbithionic acids. With excess of hydrogen persulphide inpresence of a condensing agent, they are converted int-o resinoussubstances, which probably possess the structure (11) representedin the foregoing equation. The latter compounds are decomposedby potassium hydroxide, yielding the alkali s a l h of the carbithionicacids, Ph4S2’FI; but even in the pure condition these acids arenot very stable, being slowly oxidised by atmospheric oxygen tocomplex sulphides of the following type:ArC<s-S>CAr.s sIt is interesting to observe that with the accumulation of sulphurin the molecular complex an intense colour is developed, the phenylderivative being violet and its esters deep red; but this is scarcelysurprising in view of previow work55 on the absorptive powerexerted by this element in organic compounds. Camphorcarbithionic53 T. P. Hilditch, Tram., 1910, 97, 1091.54 I. Rloch, F. Hohn, and G. Bugge, J. pr. Chcm., 1910, [ii], 82, 473; A., i,46; F. Hohn and G. Bugge, ibid., 486; A., i, 48 ; G. Bugge and I. Bloch, ibid.,572; A . , i, 60.O5 J. E. Purvis, Proc. Canzb. Phil.S’oc., 1911, 16, 155 ; A . , ii, 560; J. E. Ptirvis,H. 0. Jones, and H. 8. Tasker, Ann. Report, 1910, 250ORGANIC CHEMISTRY. 133acid has been obtained 66 from the interaction of sodium camphorand carbon disulphide, but not much interest is attached to thesubstance; it decomposes with great ease into the components.Closer attention may be directed to the esters of the aliphaticcarbothionic acids which have been thoroughly investigated.67 Twomethods of preparing these compounds have been discovered : eitherby treating an imino-ether with hydrogen sulphide (l), or from theinteraction of magnesium alkyl halide and chlorothioformicestsr (2) :(1) RC‘(:NH)mOR+ H2S=NH3+ RCS*OR.The esters in question are slowly oxidised by atmospheric oxygen,and during the process a faint glow is emitted; the phenomenon hasbeen termed ‘‘ oxyluminescence.”Further experiments with hydrogen persulphide have dealt witht.he additive compounds which it forms with quinones.58 I f thereagent is added to a solution of p-benzoquinone in an anhydroussolvent, a brilliantly blue substance is obtained, to which theoxonium structure (I) is assigned:(2) Cl.CS*OR -+ RMgX = MgXCl -I- R*CS*OR.O:C,H4: O<--s H H ->O:C,H,: 0 O:C6H4:O<SK H3(I.) (11.1Other intensely coloured substances of similar constitution areformed from quinones with hydrogen monosulphide or potassiumhydrwulphide (11).The isolation of these substances is of someimportance, since it indicates the course of interaction of mercap-tans and similar substances with quinones.I n such cases the nuclearderivative of the type (I) is obtained; but it now seems probableJithat these are formed in some manner from the oxonium additiveproducts (11) which first occur.Other researches have dealt with the conditions under whichsulphur may become a component of the quinonoid arrangement.Observations on the simple thioquinones such as S:C$H,:S are stillwanting,Sg but the work of Kehrmann and others on the azo and56 L. A. Tschugaeff and G. Pigoulowsky, Compt. rend., 1911, 153, 388 ; A., i, 797.57 M. Matsui, Mem. COX Sci. Kyoto, 1908, 1, 285 ; A . , 1909, i, 463 ; M.Deldpine, Compt. rend., 1911, 153, 279; A., i, 768; Bull. SOC. chim., 1911, [iv], 9,901 ; A., i, 944.58 M. M. Richter, Ber., 1910, 43, 3599 ; A., i, 135.59 See T.Zincke and W. Frohneberg, ibid., 1909, 42, 2721 ; A., 1909, i, 643134 ANKUAL REPORTS ON THE PROGRESS OF CHEMISTRY.CH,/\Br CH3/)Br\/I i\/A jBr\.ORGANIC CHEMISTRY. 135transitory existence of another type of sulphonium-quinone hasbeen observed63 in the interaction of hydrogen chloride with ap-acetylaminmulphoxide (I). I n the first stage of the interactiona dichloride (11) is formed, but finally the chloro-amine (IV) isisolated, together with an unstable blue substance, t o which thequinonoid structure (111) is assigned :NHAc NHAc NH NH,I 1 - + I 1 -+ I I + I \/ MeS: Cl, Me.S.01 \.( 8Me \/(1.) (11.) (111.) W . )Here the assumption of the quinonoid structure is somewhatstrengthened from analogy to the case of the o-sulphoxides ofdiphenylamine, which are successively converted by hydrogenchloride into the phenazothionium salt and chloro-amine.Another set of experiments 64 has dealt with diorthohydroxy-sulphoxides, which are converted by cold sulphuric acid intoderivatives of phenothioxin (I). It is shown -that the only satisfac-tory account of this interaction is furnished by the assumption/\ /\ A /\c1\/Me-S:OOH(1.1 (11.)that these sulphoxides behave towards acids like those of diphenyl-a.mine, and yield the sulphonium-quinones (11), which are subse-quently converted into the cyclic compounds in question.Taking a general view of the researches which have now beendescribed, it appears that the simple benzenoid sulphonium-quinones are very unstable substances; but it seems probable thatmore stable derivatives of this type may be yet obtained by selectingparticular conditions of the aromatic nucleus.A sign-post pointingin the required direction may be observed in the existence of/3-naphthasulphonium-quinone (I). This constitution has beenassigned 65 t o the dehydrothi&napht?hol which was obtained someyears previously by treating &naphthol sulphide (XI) with mild(1.1 (11- 1It is a stable, although reactive, substance, and oxidking agents.in many respects resembles 8-naphthaquinone.63 T. Zincke and P. Jorg, Ber., 1909, 42, 3362 ; A . , 1909, i, 789.ds T. P. Hilditch and S. Smiles, Zoc. cil.T. P. Hilditch and 5. Smiles, Trans., 1911, 99, 973136.ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.A direct hint as to the manner in which the sulphonium-quinonesmay be obtained is given by the behaviour of certain cyclicsulphoxides. The orthwulphoxides of diphenylamine,66 diphenyl-sulphide 67 (I), and of diphenylmethane 68 (11) yield the correspond-c1C,H4<&>C6H4 --+ , 11 4<i>C,H4 ---3- C,H,<~>C,B,CIHCl01 )ing sulphoniam salts when treated with hydrogen chloride. Thesesubstances have been isolated, but they are not very stable, andunder certain conditions readily pass into chloro-derivatives con-taining bivalent sulphur. I n the ser@ of diphenylamine anddiphenyl sulphide, chlorination of the aromatic nucleus takes place,but with the sulphoxide of diphenylmethane the meso-chloro-deriv-ative is formed.It has been shown that the formation of thesulphonium salts may be satisfactorily explained by assuming theseparation of water or of hydrogen chloride from a salt of thesulphoxide; but with regard to the subsequent formation of thechloro-derivatives nothing definite is yet known, although it seemsprobable that the change involves some procew similar to thatsuggested in the chlorination of aromatic N-acylamines.69 Whatrever the correct interpretation may be, it is noteworthy that thechange is rendered more difficult, and the stability of the sulphoniumsalts consequently raised, by the insertion of halogen or of nitro-groups in the aromatic nuclei. With the simple amino-sulphoxidequoted on a previous page, it seems that the second or “chlorina-tion ” phase of the interaction proceeds too rapidly t o permit theisolation of the sulphonium salt; but the remedy is obvious.Finally, it may be observed that the conditions which determinethe conversion of this type of sulphoxide into the sulphonium-quinone are by no means completely elucidated, for in some casesthe change may be effected without the intervention of acid; forexample, when &naphthol sulphide is oxidised under conditionswhich in normal cases furnish the sulphoxide, the sulphonium-quinone is instead produced, whence it seems probable that the66 An?&.Report, 1910, .67 K. Fries and W. Vogt, Annnlen, 1911, 381, 312 ; A . , i, 555.6g K. 3. P. Orton, Brit. Assoc.*Report, 1910.T.P. Hilditch and S. Smiles, Trans., 1911, 99, 145ORGANIC CHEMISTRY. 137former is unstable and tends spontaneously to yield the lattercompound.Alkaloids.Among the researches carried out on this class of substances,those dealing with the isgquinoline group of alkaloids sbnd outmore prominently. The synthesis of cotarnine which was effected 70in 1910 has led to that of narcotine and gnoscopine.71 Perkin hasshown that the latter alkaloid may be directly synthesised frommeconine and cotarnine merely by warming a mixture of thosesubstances in alcoholic solution :OMe/\OMeCH-0o c oOMe CHO OMe CHGnoscopine or dZ-narcotine.The product is, of course, optically inactive, and it is identicalwith the naturally occurring gnoscopine ; moreover, .by resolutionwith a-bromocamphorsulphonic acid, narcotine was obtained, thusproving gnwcopine t o be &-narcotine, and confirming the opinionof Rabe,72 who deduced this relation from the fact that gnoscopineis formed by boiling narcotine with aqueous alcohol.Since the final step in the synthesis of alkaloids of the hydrastineand narcotine type turns upon the union of the meconine 'andcotarnine complexes, efforts are being made t o discover the precisestructural conditions which govern this reaction.The yieldsobtained in the synthesis of gnoscopine are poor, but experimentshave shown that insertion of substituents such as halogen or thenitregroup into the meconine nucleus greatly facilitates the inter-action. E. Hope and R. Robinson,73 who have investigated the inter-action of cotarnine with the simplest phthalide, have been led to theconclusion that the imino-group of cotarnine is an important factorin this condensation, and this opinion is supported by the work7470 A.H. Salway, Trans., 1910, 97, 1208.71 W. H. Perkin, jun., and R. Robinson, ibid., 1911, 99, 775 ; Proc., 1910,72 P. Rabe and A. McMillan, Ber., 1910, 43, 800 ; A . , 1910, i, 335.73 Trans., 1911, 99, 1153; Proc., 1910, 26, 228.74 Annalen, 1910, 377, 223; A., i, 77.26, 46138 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of Rabe and Mcllillan. The latter investigators, approaching thequestion from the opposite side, have studied the fission of thenarcotine complex. Their experiments show that the condition ofthe nitrogen group is undoubtedly an important factor in deter.mining the stability of union between the meconine and isoquinolinecomplexes. As previous experiments have frequently shown, thesegroups in narcotine and hydrastine are readily parted by theinfluence of alkaline reagents; but when the nitrogen in thesesubstances is converted into the quaternary state by addition ofmethyl iodide, the carbon-chain remains intact, narceine or methylhydrasteine being formed with alkalis.Pictet 75 has devised a veryinteresting method of synthesis for this group of alkaloids, and i thas been successfully applied to oxyberberine. The process is accom-plished in two distinct stages. The first consists of the productionof the requisite isoquinoline derivative by a method76 which apparently is of general application. Homopiperonylamine (I) iscondensed with formaldehyde, and the product, norhydrohydrastine(1.) (11.1(11), is converted by treatment with o-nitrobenzoyl chloride intothe N-acyl derivative.I n the second stage the latter substance iscondensed with methyl opianate (111), the product (IV) beingthen treated with alcoholic potassium hydroxide. The resultingsubstance (V) was identical with oxyberberine. Attempts to reduceoxyberberine t o berberine have not yet been successful :T5 A. Pictet and A. Gams, Ber., 1911, 44, 2036 ; A., i, 807.i6 A. Pictet and T. Spengler, ibid., 2030 ; A., i, 750ORGANIC CHEMISTRY. 139(111.)On the other hand, tetrahydroberberine has been produced 77 bysynthesis.The condensation product of homopiperonylamine andhomoveratroyl chloride (VI) loses the elements of water whentreated with dehydrating agents, furnishing the isoquinoline deriv-ative (VII). The product obtained by reducing the latter isveratrylnorhydrohydrastinine, and this yields tetrahydroberberineCH,(VIII) on treatment with formaldehyde and hydrochloric acid.Previous work has shown that berberine is readily obtained fromits tetrahydrclderivative by oxidation.Although the main outlines of the structure now assigned to77 A. Pictet and A. Gams, Compt. rend., 1911, 153, 386 ; A., i, 807140 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.berberine have been placed beyond question,78 some doubt existsas to the form taken by the nitrogen group.There is generalagreement that the salts are derived from the ammonium form, butfor the free base selection must be. made from the three formulznow represented :CH,IN*OHININHThe study 'of the absorption spectra of berberine 79 and certainderivatives of known structure seems t o show that in solution thebase may exist either as the ammonium hydroxide (I) or as thecarbinol (111), according to the solvent chosen, the former beingfavoured by solvents such as alcohol or water, and the latter byether, chloroform, or aqueous solutions of free alkali hydroxide.No evidence of the existence of the aldehydic form in solution couldbe obtained 80; in fact, the case closely resembles that of cotarnine,which has been studied by the same method.Before leaving thisgroup of alkaloids mention must be made of the interesting hypo-thesis advanced by Pictet, that the isoquinoline derivatives occur-ring in plants82 probably owe their origin to some process such asthat followed in the interaction of formaldehyde and derivatives of)3-phenylethylamine, C6H,*C-&,*CH2*NH,. It is noteworthy thatthis reaction takes place very readily with formaldehyde and phenyl-alanine, C,H,*CII,*CH(COzH)*NHZ, or tyrosine,HO*C",H4*CH,-CH( CO$€)*NH2,both of which are found among the hydrolytic products ofalbuminoids. There is no doubt that of all the hypothesesadvanced t o explain the formation of isoquinoline derivatives inplants, the present is the simplest and most conformable to practicalexperience.I n the morphine group further progress hns been made in eluci-dating the structure of the substances obtained by the interactionof these alkaloids with hydrochloric acid.The constitutions of78 See W. H. Perkin, jun., Trans., 1889, 55, 63 ; 1890, 57, 992 ; 1910, 97, 321.79 C. K. Tinkler, ibid., 1911, 99, 1340.** See, however, W. H. Perkin, jun., ibid., 1910, 97, 321 ; A. Kaufniann andP. Striibin, Ber., 1911, 44, 630; A., i, 321.81 J. J. Dobbie, A. Lauder, and C. K. Tinkler, Trans., 1903, 85, 598.A. Pictet and T. Spengler, Ber., 1911, 44, 2030 ; A . , i, 750ORGANIC CHEMISTRY. 141apomorphine 83 and of thebenine 84 have been successfully attackedin former years, and morphothebaine85 has now yielded to similarmethods.Previous work led to the suggestion of the followingformula (I) for this substance :H, NMe(I.) (11.) (111.)Morphothebaine has been submitted to exhaustive methylation,and on oxidisiug the product a carboxylic acid was obtained, whichwas found to be derived from a trimethoxyphenanthrene. I f thestructure suggested for morphothebaine is correct, this acid musthave the structure represented by (11), and when the carboxyl hasbeen replaced by a methoxyl group86 the product must be3 : 4 : 6 : 8-tetramethoxyphenanthrene (111). Setting out fromo-nitrovanillin methyl ether (IV) and 2 : 4-dimethoxyphenylaceticacid (V), Pschorr has succeeded in synthesising a substance of this/\f:HO /\1OMeCH;CO,HMe O!,,!N 0, \/ 0 Me OMe(IV.) ( V . )structure, and i t is identical with that obtained from morpho-thebaine; hence the suggested formula for this substance is con-firmed.Other work in this group has been commenced with theobject of attacking the constitution of morphine by breaking upthe cyclic complex which contains the two orthochydroxyl groups.The preliminary stage in this investigation87 appears to have beensuccessfully accomplished by treating morphine in solution withnitrous vapours. An orange substance, probably a quinonitrol, isthen formed, and this is decomposed by waher into a carboxylicacid, which has been termed morphinic acid. The developmentof this attack will be interesting. Numerous interesting derivatives84 R. Pschorr, H. Einbeck, and 0. Spangenberg, Ber., 1907, M , 1998 ; A., 1907,y4 R.Pschorr and H. Loewen, Amtalen, 1910, 373, 51 ; A., 1910, i, 424.y5 R. Pschorr and G. Knijffler, ibid, 1911, 382, 50 ; A., i, 669.86 R. Pschorr and H. Rettberg, ibid., 1910, 373, 51 ; A., 1910, i, 423.87 H. Wieiand and P. Kappelmeier, ibid., 1911, 382, 306 ; A . , i, 743.i, 635142 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of these alkaloids have been prepared,s8 but a detailed descriptionof their behaviour is unnecessary, for this has not yet been broughtto bear on the structure of the parent substances.Turning t o the group of cinchona alkaloids, we again findimportant progress in the work of synthesis. With the conversionof cinchotoxine into cinchoninone, Rabe 89 has accomplished thefinal stage of the synthesis of the bridged bicyclic system whichcharacterises this group of alkaloids.Since the process is likely tobe of importance in the complete synthesis of cinchonine, it maynow be fully described. Cinchotoxine (I) when treated with hypo-bromous acid furnishes the N-bromo-derivative (11), which, inpresence of sodium ethoxide, readily loses hydrogen bromide, beingC*H,:CH*CH-~H--CH, *YH--CH, *yH--CH,I ?H2 I yH2 j(p:' I -+ 7% I I y H 2 IC,H,N-CO CSH,S.C0 C',U,N.h*NBr CH2 *N--CHIi yHz ICH,*NH CH2I(1 1 (11.) (111 1converted into cinchoninone (111). Previous experiments 90 haveshown that the ketone may be reduced to the secondary alcoholcinchonine. The same investigator has shown that oximinoquino-toxine 91 may be resolved into the nitrile of meroquinine and quinicacid, but since the process has been carried out some years previ-ously with cinchotoxine (cinchonicine) no further comment isnecessary.A synthesis of the quinoline portion of the cinchoninecomplex has been effected 92 by treating quinoline methiodidewith potassium cyanide. The 4-cyano-derivative (I) which is thenformed yields, on oxidation with iodine, the methiodide of 4-cyano-H CN/\/\I l l\/\/N/\6H3 Me I(1.1 (11.)quinoline (11). This may be further oxidised to the a-quinolone,88 M. Freund and E. Speyer, Ber., 1911, 44, 2339 ; A . , i, 909 ; L. Knorr andP. Roth, ibid., 2754 ; A . , i, 1014 ; M. Freund and K. Lederer, ibid., 2353 ; A., i,910.8s P. Rabe, ibid., 2088 ; A., i, 742.90 P. Rabe, ibid., 1908, 41, 67 ; A ., 1908, i, 100.91 P. Rabe and E. Milarch, Annalen, 1911, 382, 365 ; A . , i, 741.sf! A.Kzufmann and R, Widmer, Ber., 1911, 44, 2058 : A., i, 749ORGANIC CHEMISTEY. 143which, on distillation with zinc dust, gives the nitrile of cinchonicacid. Other work has dealt 93 with the fluorescence of these alkaloidsand their derivatives, and it has been found that the wavelength ofthe emitted light is influenced by slight changes in the constitutionof the fluorescent molecule. In conclusion, it may be observed thatthose particularly interested in this group of alkaloids will findthe subject admirably dealt with in a recent monograph.94The recently discovered alkaloid, dioscorine, C13H1902N, has beensubmitted to a closer examinationF5 which has revealed the presenceof 8 lactone ring and the imino-methyl group.Exhaustivemethylation converts this substance into a hydrocarbon, CllH14, andthis is considered to be a derivative of cyclohexane, for, on additionof hydrogen bromide and removal of this substance with hotquinoline, another hydrocarbon is obtained which yields o-toluicacid on oxidation. A preliminary formula has been propwed toexpress these relations, as well as the fact that the physiologicalaction of this alkaloid is similar to that of picrotoxine.The physiological importance of the alkaloids containing theglyoxaline arrangement lends a general interest to the elegant syn-theses recently effected in this group. The discovery96 that thephysiological behaviour of ergot is partly due to the powerfulactivity of an aminoethylglyoxaline has been rapidly followed bythe synthesis of the c0mpound.~7 The steps involved are toonumerous to be repreented fully in this pIace, and it must sufficeto observe that the 2-thiol-4(or 5)-aminoethylglyoxaline (I) isobtained by interaction of potassium thiocyanate and diamineacetone :I I CH,*NH, bH2*OH.bH,Cl CH,* C H, *NH,(1.1 (11.) (111.) (IV. 1On treating this substance with nitric acid, the sulphur iseliminated, and the amino-group is replaced by hydroxyl; theproduct (11) yields the chloro-derivative (111) when submitted tointeraction with hydrogen chloride. Thence, by means of potassiumcyanide and subsequent reduction, 4(or 5)-/3-aminoethylglyoxaline(IV) is obtained, the product being identical with that isolated fromergot.The chloro-derivative which is above formulated (111) has served93 P.Rabe and 0. Marschall, Annalen, 1911, 382, 360 ; A . , i, 741.94 Comandueci, Samnclmy. chemisch. VoTtrage. , 1911, 16, 141.y5 I(. Gorter, Bee. trav. chim., 1911, 30, 161 ; A., i, 222, 561.y6 G. Barger mid H. H. Dale, Trans., 1909, 97, 2592.97 F. L. Pyman, ikid., 1911, 99, 668144 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.it3 the starting point of the synthesis of histidine.98 Thus, byheating it with ethyl sodiochloromalonate, an ester is formed, whichmay be hydrolysed, yielding the chloreacid (V), and the latter, byCH~*CHC~*CO,H CH,*CH(NH,)-CO,H(V. 1 VI. 1treatment with concentrated aqueous ammonia, in turn furnishesracemic histidine (VI).This noteworthy synthesis has beenrendered complete by the resolutiou of the inactive substance, andthe laevo-isomeride was found to be the same as that obtained fromnatural sources. The synthesis of other important physiologicallyactive substances in this group has been eff ected,99 but considerationsof space preclude a detailed account.It remains to be mentioned that the structure of the alkaloidhypaphorine has been elucidated by the demonstration 1 that it isthe betaine of tryptophane; in fact, the substance may be preparedby methylating tryptophane and decomposing the product withsilver oxide.Chlorophyll.Apart from the isolation of the fundamental pyrrole derivatives,the main feature of the work dealing with chlorophyll and haematinhas in the past been the preparation of a number of complexproducts of decomposition.To those not actudly engaged inthe woFk, the discovery of a large number of such derivativesand the lack of any definite information as to their nature naturallyappears to obscure the few simpler facts already known with regardto the parental compounds. However, in the year now underreview, Willstiitter has s h far succeeded in reducing to order thetangled mass of facts which hitherto represented the chemistry ofchlorophyll, that a general outline may now be sketched of thechemical nature of that substance and of the relations of itsdecomposition-products.The fresh material brought t o bear on the discussion of thechemistry of chlorophyll has been obtained by two distinct lines ofresearch ; either by investigating the substances isolated togetherwith chlorophyllin extrating the plant tissue, or by examining thedegradation produck obtained on attacking the chlorophyll nucleuswith various reagents.The amorphous chlorophyll, which isobtained by extracting the natural maberial under carefully regu-98 F. L. Pyman, Trans., 1911, 99, 1386.G . Barger and A. J. Ewins, ibid., 2336.P. van Romburgh and G . Barger, ibid., 2068ORGANIC CHEMISTRY. 145lated conditions, contains an unvarying amount-about 33 per cent.- o f phytol.2 The thoroughness with which this important relationhas been established may be imagined from the fact that the chloro-phyll from two hundred different kinds of plants has been compared.It may be observed in passing that the crystalline chlorophyllobtained by Borodin and others does not contain phytol, and ittherefore cannot be the unaltered natural pigment.The cautious hydrolysis of amorphous chlorophyll with cold dilutepotassium hydroxide removes phytol and methyl alcohol, furnishingthe potassium salt of a tricarboxylic acid which has been termedchlorophyllin.Hence it appears that the amorphous chlorophyllof nature is merely the di-ester of this chlorophyllin, in which twocarboxyl groups are esterified by methyl alcohol and by phytolrespectively,3 the third probably remaining free. The relationbetween the two substances are represented as follows:Of the two ethereal groups in question that containing the methylis by far the more stable, 50 that by using other hydrolytic agentsthe phytolic residue may be removed, leaving the methyl chloro-phyllin-a substance which is better known as chlorophyllide.Further investigation has elucidated the nature of crystallinechlorophyll,4 and its relation to the natural pigment.It has nowbeen found that the crystalline substance does not contain twomethoxyl groups as formerly supposed, but instead embracesmethoxyl and ethoxyl in equivalent proportions. This a t oncefurnishes a clue as to the method of its formation from amorphouschlorophyll, for it is prepared by extracting the plant substancewith ethyl alcohol, and free phytol is always simultaneouslyobtained. There is now abundant proof to show that prolongedcontact of the alcoholic solution of chlorophyll with the plant+substance permits the alcoholytic action of an enzyme, termedchlorophyllase,6 which is contained in the latter.Experimentsmade with amorphous chlorophyll and chlorophyllase in etherealsolution show that phytol is readily eliminated by this enzyme,chlorophyllide being formed. If ethyl alcohol is used as the solvent,the liberated carboxyl group is re-esterified, giving ethyl chloro-phyllide, and with methyl alcohol the new crystalline chlorophyll,methyl chlorophyllide, is produced. The ethyl chlorophyllideR. Willstatter and A. OppB, Amzalen, 1910, 378, 1 ; A . , i, 140.R. Willstatter and A. Stoll, ibid., 18; A . , i, 391.R. Willstatter and A.Stoll, loc. cit. 1bid.REP. --VOL. VIII 146 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.obtained in this manner is identical with the substance usuallytermed crystalline chlorophyll. Besides revealing these interestingrelations, the researches with this group of substances have led tothe synthesis 6 of chlorophyll from chlorophyllide and phytol bymeans of an enzyme, and there is scarcely room for doubt that thenat,ural synthesis of the pigment takes place on these lines. Asummary of the connexion between these substances is formulatedbelow :E H & “ Crystalline ” chlorophyll or+--- ethyl chlorophyllide + phytol,“ Amorphous ” chlorophyll -f - or phytyl chlorophyllide, I K(CO,°CI,oH,,)(CO,Me)*CO,H. enzyme R( CO,Et)(CO,Me).CO,H.-Chlorophyllide + phytol ’ 1 R(C02H)2*C0,Mr.‘3 Chlorophyllin +- CH,-OH + phytolThe investigation of the behaviour of chlorophyll and otherchlorophyllides with various hydrolytic agents has shown that eitherof two kinds of interaction may occur.Acid hydrolysis leads toelimination of the magnesium, whilst hydrolysis with alkalihydroxides leaves this metal intact and effects ot>her changes in thechlorophyll nucleus. It is therefore clear that successive stages inthe degradation of the complex may be attained by the consecutiveapplication of these reagents, the intermediate substances obtaineddifi’ering according to the order in which the application is made.For example, with alkali hydroxide under intensified conditions,phytyl chlorophyllide (chlorophyll) yields the “ phyllins,” and thesewith acid hydrolytic agents yield in turn the “porphyrins.” Onthe other hand, if the chlorophyllide be first submitted to the inter-action with acids, the “ phaeophorbides ’’ are produced, which areconverted by mild alkaline hydrolysis into a mixture of (‘phytcsrhodin-g ” and “ phytochlorin-e.” Finally, when (‘ phytochlorin-e ”is treated with hot alcoholic potassium hydroxide, carbonic acid iseliminated, and a member of the “ porphyrin ” seriw is produced.Rw2=)3*CO, + phyllins ””id, porphyrinsChlorophyll or /+ - C02+alkali Iphyi yl chlorophyllide phaeophy tin or phytochlorin-e >* phytylphaco- 2; phytorhodiu-gphorbide phytolPhytorhodin-g and phytochlorin-e have figured very prominentlyin the researches of the past year, and under close examinationthey have led to very important results.These substances are6 R. Willstatter and A. Stoll, Zoc. citORGANIC CHEMISTRY. 147produced from all other known phaeophorbides which contain thechlorophyll nucleus free from magnesium :-+ phytochlorin-eC hlorophyllin -+ yhaeophorbinChlorophyllide --t phaeophorbideMethyl chlorophyllide --+ methyl phaeophorbide --+ phytorhodir -yXthyl chlorophyllide -+ ethyl phaeophorbide -+and quantitative experiments 7 conducted with chlorophyllides ofvarious origin have shown that the two compounds in question arealways produced in the approximate ratio :-7phvtochlorin-e - 2.5ph y torhod I n-g- -1 'This circumstance may be interpreted either by supposing thatthe substances in question are contained in the required proportionby the chlorophyll molecule, or that they are separately producedby the hydrolysis of two kinds of the pigment.The formeralternative must be rejected, for the molecular weight of eithersubstance alone approximates to that of chlorophyll when allowanceis made for the phytol and methyl alcohol contained therein. Theconclusion thus reached as to the heterogeneity of the naturalpigment is not by any means novel, for it has been previouslyadvanced by several other workers, of whom, it may be noticed,Stokes was the earliest. However, definite proof has been nowattained by the separation of a chlorophyll derivative into twocomponents. The ethyl phaeophorbide, which is derived from" crystalline chlorophyll " by hydrolysis with cold acids, may beresolved by crystallisation 8 under special conditions into the a andb componeots.Moreover, it has been found that alkaline hydrolysisof the a and b ethyl phaeophorbides thus obtained yields respectivelyphytochlorin-e and phytorhodin-g. A similar separation, althoughnot so complete, has been made with crystalline chlorophyll, which-+ ethylphaeo-phorbide I LC .C37I&o5.~N4&lg.Ethyl chlorophyllide, contains 50 % of :tc t : b = 2 . 5 : 1b.C37H99%.5N*MbU hydt ate.c, IH37%.,N,M&(c -+ Phytochlorin-eCs4H3,O5N 4, also as hydrate (in varying proportions).b -+ Phytorhodin-gC34H3*07%R. Willstatter and M. Isler, AnnaZen, 1911, 380, 154 ; A., i, 392.E. Willstiitter arid M.Utzinger, ibid., 382, 129 ; A., i, 659.L 148 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.consists of the bluish-green a and the yellowish-green b forms. Thescheme on p. 147 represents the connexion between these substances.A clue to the relation between a and b chlorophyll has also beenobtained. Since the final products of degradation of phyto-chlorin-e and phytorhodin-g are the same, it is evident that bothcontain the same general structure, which, according to theanalytical data, must be present in either substance in a differentstage of oxidation. With this conclusion as premise, it follows thattho same relation holds between ar and b-chlorophylls, for there isno reason to suppose that oxidation or reduction occurs during thehydrolytic processes.This conception of the relation between thetwo chlorophylls is of importance, since it indicates that in theprocesses of assimilation the pigment may assume a chemicalfunction in addition to the physical role which is usually ascribedto it.Phytochlorin-e and phytorhodin-g are by no means the onlydegradation product8 of these types which have been isolated fromchlorophyll, for by adopting different conditions of hydrolysis itis possible t o obtain numerous isomerides.9 To discuss in detail oreven to enumerate the various cases would not only be inappropriate,but would alao add confusion t o a theme which is already suffi-ciently compJex, for as yet the bearing of these substanc_es on theconstitution of chlorophyll remains somewhat obscure.The preciserelations between the various phytorhodins and phytochlorins arenot yet firmly established, but it may be noticed that the substanceschiefly differ in their varying acidic or basic power. As Willstatterhas pointed out, there is no doubt that the existence of so manyisomerides is connected with the Occurrence of three carboxylgroups and a t least as many imino-groups in the chlorophyll complex.I n chlorophyll itself, where two of the carboxyl groups are esterifiedwith phytol and methyl alcohol, the third acid group almost certainlyexists in the lactam arrangement *CO*NH*, or the hydrated formthereof. It is therefore conceivable that under certain conditionsthe lactam system i n chlorophyll might undergo fission and sub-sequent regeneration ; moreover, if a different aminegroup isinvolved in the new lwtamic system, it is clear that an isomericchlorophyll of different basic or acidic character will be formed. Agraphic representation of this hypothesis is attempted in the follow-ing scheme; the different carboxyl and aminqroups are letteredaccordingly :R. Willstatter and M. Utzinger, Eoc. citORGANIC CHEMISTRY. 149Isomeride. Chlorophyll.c3, *CO,-C,GH,,HZ9 *CO;CH, Pa.y. N 3 ‘ Y O YMg i *NH PIsomeride.There is, indeed, experimental evidence in support of thehypothesis, for it is found when chlorophyll co has been kept forsome time in light petroleum, that phytochlorin-g is formed10 onhydrolysis, and not the e-isomeride, which is obtained from freshmaterial. Accordingly, there is no objection to assuming that thesame kind of process may take place with alkaline reagents, andwhen it is considered that these liberate two other carboxyl groupsthe increased possibiilities of isomerism a t once become apparent.Moreover, it is clear that the nature of the alkali will, to a, certainextent, determine which carboxyl and which amino-group willcombine t o give the lactam system.At present all that can be tentatively said of the structures ofthe phytochlorins and phytorhodins is that they are respectivelydi- and tri.carboxylic derivatives of a complex which contains thelactamic and pyrrolic arrangements :Phy tochl orin, Phy torhodin.Thus i t is seen that on passing from the “chlorin” to the‘‘ rhodin,” a carbon group of the nucleus is oxidised to carboxyl;but it may be observed that this step has apparently not yet beenrealised in experiment.Turning finally to consider the ultimate degradation products ofthis pigment, it is found 11 that reduction of the chlorophyll systemby various methods yields i ~ ’ mixture of three pyrrole derivatives:hzemopyrrole, isohmnopyrrole, md phyllopyrrole. The full evidencefor the structures assigned t o these compounds cannot be herelo R. Willstatter and M. Utzinger, Zoc. cit.l1 R. Willstatter and Y. Asahima, Anmatem, 1911, 385, 188 ; A., 1912, i, 41150 ANN'CTAL REPORTS ON THE PROGRESS OF CHEMISTRY.given; but it leads with apparent certainty to the followingformulae :Me- Et Me-Et Mc-EtMe' 'Me MA INH\/ ' IMeNHPhyllopyrrole. Hamopyrrole. isoHzmopyrrole.\/ \\/NHOn the other hand, oxidising agents yield products12 ofnature, such as methylethylmaleinimide and hzmatinic acidMeC==yEt60 co\/NHI n last year's reportof resemblance betweenMeC== ~* g;C H,*C N,*CO,H\/NHHaeniatinic acid.attention was drawn to the manyacidicpointschlorophyll and hzmatin, and recent workhas given emphasis to the likeness, for i t has been; found that thetwo haemopyrroles and phyllopyrrole are also obtained by reducinghzematin. With regard to the constitution of the latter, it maybe observed that the accumulated data have proved sufficient for adetailed discussion of the question and for the establishment of aprobable constitution for the substance. I n this place more cannotbe done than to refer the reader to the valuable summary ofPiloty,*3 since most of the data contained therein have beenpreviously published and discussed in the report of last year.The foundation of any formula assigned to haematin and its con-geners must be laid on the structures of phyllopyrrole and the hzm*pyrroles, and it must be confessed that the present formulae forthese substances can only be accepted with some hesitation, in spiteof the concluffive manner in which the analytical evidence favoursthem. The doubt arises from the recent synthetical experiments ofKnorr,lQ who has prepared 2 : 4-dimethyl-3-ethylpyrrole (11) byreducing the hydrazone of 3-acetyl-2 : 4-dimethylpyrrole :fiAc-sMe fiEt-gMeCMe CH -A CMe CH\/NH(1.1 (II.)The product was not identical with hzmopyrrole obtained fromthe natural pigment, although there was a strong resemblancebetween the two substances. To be obliged to leave the matter inthis condition is somewhat unsatisfactory, but a t the present statel2 R. Willstiitter and M. Utzinger, loc. cit.Is 0. Piloty, Annalen, 1911, 377, 314; A., i, 92.l4 L. Knorr and K. Hew, Bey., 1911, 44, 2758 ; A., i, 1019ORGANIC CHEMISTRY. 151of affairs it is scarcely profitable to discuss the alternative waysout of the difficulty, and hence the satisfaction of presenting a morecomplete narrative must be left to a reporter of the future.Attention has not been confined to the nitrogenous complex ofchlorophyll, and the alcohol with which this is esterified has beenvery thoroughly examined.15 The novel character and the impor-tance of this substance offer some excuse for reviewing the chieffacts which elucidate its constitution. Phytol, C,,H,*OH, is anunsaturated alcohol, and the situation of the ethylenic linking maybe inferred from the products of oxidation with Ozone or chromicacid. The latter-named reagent furnishes a mixture of phytenicacid, C,,H3,*G02H, which contains the same number of carbonatoms as the alcohol, and a ketone of the formula Cl5HS0O, whenceit is evident that phytol is a primary alcohol, containing theetheiioid group between the fifth and sixth carbon atoms. More-over, since phytenic acid readily yields a stable lactone, it appearsthat the unsaturated group is situated in the By-position withrespect to the terminal carbon atom. Of the three alternatives forthe arrangement of the first five carbon atoms, that outlined belowis the most probable; the other two need not be here described, butH O*CH,-CH Me*CMe: C1,H3,,the chief circumstance favouring that quoted is the occurrenceof the same peculiar arrangement in other parts of the molecularstructure. The Ozonolysk of phytol yields a ketone, C15H300, whichmay be transformed by a suitable process into the saturated acid,C,,H,O,, containing one carbon atom less; it therefore containsthe ketomethyl, *CO*CH,, arrangement. Further, when this ketoneis treated with oxidising agents a series of three other ketones isobtained by successive removal of pairs of carbon atoms, togetherwith acids which contain one carbon atom less than the ketonicproducts; thus it appears that these substances also are methylketones, and accordingly it follows that the seventh, ninth, eleventh,and thirteenth carbon atoms of phytol have a methyl group attached(see I). With regard to the structure of the remaining group ofseven carbon atoms which is represented within the brackets in theC,,H,,:CMe=CHMe.CH,*OH -+ C,,H,,O or C,, H,,*CO*CH, -+.7 9 11 13 1 Me M e Me Me Me Me i Me Me MeHO*CH,*qH*y=~-C:H*~H*~K* -vH*yH*FH*Me(1.)above formula, nothing is yet known with certainty; but on generall5 R. Willstatter, E.W. Meyer, and E. Hiini, Annalen, 1910, 378, 73 ; A., i, 144152 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.grounds the structure given seems probable. The methyl ketoneswhich have been prepared from phytol are interesting, not onlyon account of their bearing on the structure of that substance, butalso because of certain anomalies in their physical properties. Anexplanation of the latter has been sought in the assumption thatthe samples obtained consisted of the enolic isomerides.This brief account of the investigation of phytol may be closedby mention of the hypothesis put forward to explain the naturalsynthesis of the substance. It has been pointed out that the peculiarstructure of the alcohol suggests that it is formed by polperisa-tion of some hydrocarbon such as isoprene, four molecules beingcondensed by the intervention of water and hydrogen :4CbHg + HZO + 3Hz= C20H400.In spite of the slender basis on which this hypothesis lies, it isparticularly attractive on account of the genetic connexion whichit reveals between phytol and the terpenes, caoutchoucs, and othergroups of compounds.In concluding the report on organic chemistry i t has almostbecome a rule to remark that much important work of the pastyear has not been reviewed. The omissions in the present case willcertainly be evident to any who read the foregoing pages.The writers, feeling that a compromise has of necessity beenmade, wish to point out that in making a choice of the subjectsto be treated they have been guided by two motives: to choceefrom among the more important branches those in which sufficientprogress has been made to form a connected story, and from theminor subjects to select those which appeared of a novel characteror which enlisted their personal sympathies. The excuse for thelatter mode of selection is that it has added something more ofinterest to the work.F. D. CHATTAWAY.S. SMILES

ISSN:0365-6217    

DOI:10.1039/AR9110800049

出版商:RSC    

年代:1911

数据来源: RSC

摘要:

ANALYTICAL CHEMISTRY.REPORTERS on the progress of analytical chemistry in other yearshave sufficiently emphasised the fact that in this branch of chem-istry it is scarcely possible t o fulfil the object of the Reports asset forth in the “ Introduction ” to Vol. I. (1904). Recognisingthis fact, the writer of this report has ventured to depart some-what from the plan on which the corresponding report of previousyears has been based. I n the first place, fewer subjects have beentreated of, but these few subjects have been treated at greaterlength, the number of references is much smaller, and a ratherlarge proportion of these references are to papers published priorto 1911. This has necessitated the abandonment of the more minutesubdivision of the subject adopted in recent years, for the writerhas frankly abandoned the attempt to cover the whole groundof aualytical chemistry.I f , for example, no reference to wateranalysis is found, it must not be supposed that the writer holdsthe opinion that nothing useful has been accomplished in thisbranch during the year, but rather that he thinks this and othersubjects can be treated in a more interesting and connected mannerif left to the reporter of another year.General.An important communication has been made this year on thesubject Gf melting-point determinations. It was the author’s dutyto recommend a standard apparatus and standard procedure forincorporation in the forthcoming United States Pharmacopeia,but his work has a more general value than this might suggest.I neffect, he shows that the records of melting points, which aregenerally regarded as so important that they are copied into everyjournal of abstracts whatever else is omitted, are, in fact, of littlevalue, and will remain of little value until some uniform methodof determining melting points is agreed on. He also lays stresson the fact that a melting interval should always be reported.Although he is chiefly concerned with pharmaceutical preparations,which are often so far from pure that they exhibit a very wide15154 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRYmelting interval, there are a great many sharp melting points onrecord which no one except their authors has ever been able toconfirm, working with the purest material obtainable.The generaladoption of the custom of reporting a melting interval involvesa definition of its beginning and ending, but this is not very difficult,as the paper under notice shows. The apparatus recommendedby the author is of the simplest description.1By means of Bousfield’s pyknometer,2 it is possible to determinethe density of a liquid with an error of less than rfl in the fifthplace of decimals, but some 250 C.C. of the liquid are required, andthe degree of accuracy attained is, after all, not much in advanceof that attained with quite astonishing rapidity by routine workersin laboratories where the densities of large numbers of diluteaqueous solutions have to be determined daily. It is now shownthat a density determination accurate to +5 units in the sixthdecimal place may be made with simple precautions, using no morethan 25 C.C.of liquid.3The investigation of capillarity constants, easily determined byTraube’s dropping method, is one of the simplest of the physicalmethods applicable to analytical chemistry, but one which has beenalmost entirely neglected. The method should prove of specialvalue for the detection of minute traces of colloid poisons and forthe determination of adsorption- coefficient^.^This is presumably the place to call attention to a remarkablediscourse delivered a t the Royal Institution by Sir J. J. Thomsonon a new method of chemical analysis. It is found that the positiverays with which the author has been working for some years afforda means of gaining an insight into the nature of the gases in avacuum tube, and render possible a chemical analysis capable ofdetermining whether, for example, oxygen is present, and, inaddition, whether it is in the atomic or molecular condition or inmore complex aggregations.The rays after passing through a finetube in the cathode are exposed simultaneously to magnetic andelectric forces, the former so arranged as to produce a vertical,the latter a horizontal, deflexion of the rays. When neither forceis acting, the rays strike a point, 0, on a screen placed a t rightangles to their direction, but under the influence of both fieldsstrike another point, P. The length of the vertical line PN isproportional to the deflexion produced by the magnetic field, andhhat of the horizontal line ON t o the deflexion produced by theG.A. Menge, U.X. Treasury Dept., Hygienic Lab. K i d l e t i n 70.W. R. Bousfield, Trans., 1908, 93, 679.8 H. Hartley and W. H. Barrett, ibid., 1911, 99, 1072.4 I. Traube, Ber., 1911, 44, 556; A., ii, 328AN A L Y T I C A 1, CHEMISTRY. 155electric field. It is known that P N = A e : / v and ON=Bc/mv2,m-here A and B are constants depending on the strength of thefields and the geometrical data of the tube, e is the charge on theparticle, m its mass, and u its velocity; then - = - ON When6 / 5 *m-the rays strike a photographic plate, i t is affected, and on develop-ment yields a permanent record of their deflexion. From the valuesfor ON and PX obtained by measurement on the plates, one candetermine the value of m/e, which for the same type of 'carrier is aconstant, and this value can be compared for different rays bymeasuring the values of ON and PAr.The locus of P is a parabola,and not a point, because the rays are not all moving with the samevelocity, the slower ones suffering greater deflexion. Each type ofcarrier produces its own line on the plate, and there are as manycurves on the plate as there are kinds of carriers, but, from thedimensions of the curves there can at once be calculated theiratomic weights. It is in this last respect that the advantage ofthe new method over spectrum analysis is most obvious. The authorshows how the application of the method to atmospheric nitrogenmust have pointed to the existence of another gas with an atomicweight of 40, but the chief use of the method will, no doubt, bein the determination of atomic weights of forms of matter whichhave only a transient existence and exist in minute quantity only.The rays are registered within a millionth of a second of theirformation, and the metEiod will detect quantities of gas too minuteto produce any indication in a spectroscope, whilst if as much as0.01 milligram is available, an atomic-weight determination accurateto 5 1 per cent.is possible.5From among a large number of pieces of new apparatus describedwithin the year, attentioc may be called to an apparatus for theautomatic extraction of aquems liquids by means of specificallylighter solvents,6 and to as apparatus for precipitating, filtering,and drying in an inert gas,' these being operations which manyworkers will be glad to find simplified for them.I n connexion with quantitative microchemical analysis, severaluseful pieces of apparatus have beep devised, the most notableperhaps being a micrdilter? and an apparatus for volumetricanalysis with small quantities of 1iquid.Q[vi].21, 225 ; A . , ii, 457.Sir J. J. Thomaon, Xakwe, 1911, 86, 466 ; compare also Phi?. Mag., 1911,R. Kempf, Chem. Zeit., 1910, %, 1365; A . , ii, 106.J. B. Firth and J. E. Myers, PTOC., 1911, 27, 96.J. Donau. Momtsh., 1911, 32, 31 ; A . , ii,,225.F. Pilch, ibid., 21 ; A . , ii, 225156 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Gas Analysis.None of the well-known methods for the determination of nitrousoxide in a gaseous mixture of which it is the principal constituentis quite satisfactory.Explosion with hydrogen may lead to resultsfully 2 per cent. below the truth, far too large an error when theobject of analysis is t o compare two commercial brands of com-pressed gas of which few contain less than 95 per cent. and someover 99 per cent. of nitrous oxide. Exact results may be obtainedby the following indirect method. A measured volume of the gasis passed over ignited copper gauze previously reduced in a currentof hydrogen, and the current of gas is followed by one of hydrogen,t.he moisture formed during this second stage of the experimentbeing collected in a tared drying tube.The method, of course,measures not nitrous oxide alone, but the oxygen, free andcombined, in the gas. I n practice, however, the only correctionusually necessary is that corresponding with the percentage ofmoisture of the gas, since commercial nitrous oxide appems to befree from compounds of oxygen other than nitrous oxide, andalthough oxygen itself can be detected in nearly every sample, itsamount seems never to reach 0.1 per cent.10Nitric oxide is absorbed completely and quickly when shakenin a Hempel pipette with a saturated solution of ferrous sulphatemade faintly acid with sulphuric acid; but the method fails inpresence of nitrous oxide on account of the high solubility of thelatter gas in water, even when this is saturated with a salt such asferrous sulphate.Previous saturation of the ferrous sulphatesolution with nitrous oxide changes the large positive error to asmall, but not insignificant, negative one, for the absorption ofnitric oxide by the liquid reduces its capacity to hold nitrous oxidein solution, and this gas is set free. Divers' sodium sulphitemethod 11 possesses no advantages over the ferrous sulphate method,and the absorption is much dower. The gravimetric methods forthe eetimation of nitric oxide require such elaborate precautionsto renaer them quantitative that they are rarely applicable. Amongvolumetric methods, that which makes use of permanganate hasthe advantage that this reagent is without action on nitrous oxide,but the apparatus recommended by LungeB requires t o have itsair mntenh displaced by carbon dioxide, and this leads indirectlyto errors which cannot be kept below 2 per cent.An apparatushas at la& been designed which overcomes these difficulties, and10 C. BaskervilIeandR. Stevenson, J. Ind. Eng. Chon., 1911, 3, 579.11 E. Divers, Trans., 1899, 75, 82.12 G. Lunge, Zeitsch. angcw. Chem., 1890, 8, 567ANALYTICAL CHEMISTRY 15’7by its aid the accurate estimation of nitric oxide becomes oneof the easiest of analytical operation^.'^A test capable of detecting as little as 0.05 C.C. of hydrogen inadmixture with large volumes of other gases consists in passingthe gaseous mixture through a solution of sodium molybdatecontained in a test-tube, in which is also placed a piece of recentlyignited platinum.The substitution of palladium for platinumincreases the sensitiveness of the test, but requires certain precau-tions. I f the gaseous mixture contains hydrogen, the liquid in thetube assumes a greenish-blue mlour, a single bubble of purehydrogen yielding an intense blue. The gas to be tested must befree from certain other gases, of which hydrogen sulphide andcarbon monoxide are the mwt commonly occurring. Neithermethane, ethylene, acetylene, nor their homologues interfere.Methods and apparatus have been described for concentrating onpalladium sponge the hydrogen from large quantities of gas con-taining only minute traces of hydrogen, and subsequently demon-strating the presence of this hydrogen by means of the molybdatereagent .I*Zn0rgam.c Analysis.Ebler has still further developed his method of qualitativeanalysis which avoids the use of hydrogen sulphide.16 As originallydescribed, it involved the use of a rather troublesome process forthe separation of arsenic.It is now recommended that the separa-tion of arsenic should be the first operation of analysis, and thatit should be accomplished by distillation with hydrochloric acidand hydrazine bromide.16 The directions for the treatment ofinsoluble residues have been modified so as to be applicable tocomplex cyanides, and so as to avoid the formation of insolublesubstances of the type of chrome ironstone, which were occasionallyformed when working according to the original scheme, and gavetrouble in the subsequent analysis.17 Another method of qualitativeanalysis which avoids the use of hydrogen sulphide is that ofPamfi1,’s but this requires much more elaboration before it caa berecommended.1’Among qualitative reactions of the metals, the following perhapsI‘ C.Zenghelis, ibid., 1910, 49, 729 ; A., 1910, ii, 1106.l5 E. Ebler, Zeitseh. anorg. Chesn., 1905, 48, 61 ; A., 1906, ii, 126 ; Zeitsch. anal.l* P. Jannasch and T. Seidel, Ber., 1910, 43, 1218 ; A., 1910, ii, 1076.l7 E. Ebler, Zeitsch. anal. Chem., 1911, 50, 603, 610; A., ii, 932.I* G. P. Pamfil, Bon. Sei., 1910, [iv], 24, 11, 641 ; A., ii, 1030.l9 D. A. Roche, ibid., 1911, [v], 1, I, 87; A . , ii, 1031.L. Moser, Zeitsch. anal. Chem., 1911, 50, 401 ; A., ii, 598.Chm., 1908, 47, 555158 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.deserve notice here.Titanium trichloride serves for the detectionof one part of gold chloride in thirty million parts of water.20 Asolution of disodium 1 : 8-dihydroxynaphthalene-3 : 6-disulphonateserves to detect as little as 0.0008 milligram of chromium if presentas chromate.*' By the simultaneous action of nitrites and hypo-sulphites on solutions of nickel salts, a substance is formed whichgives the solution a colour resembling permanganate. The colouris not given by cobalt salts, and is sufficiently intense to serve forthe detection of nickel in presence of much cobalt.22 Anotherreaction which serves for the differentiation of cobalt and nickeldepends on the formation, in neutral solutions, of precipitates ofbasic chromate.The basic chromates of nickel and cobalt are bothbrown, but that of cobalt is much redder. However, their differen-tiation depends less on the colour of the precipitates than on thefact that the cobalt salt, unlike that of nickel, adheres firmly toglass vessels, and is precipitated even in the cold from comparativelydilute solutions.23 A microchemical reaction of nickel and cobaltis referred to later in this report.Possibly of more importance than any of thme qualitativereactions is the observation that in ordinary systematic qualitativeanalysis it is impossible t o detect small quantities of barium (up to50 milligrams in a 1 gram sample) by ammonium carbonate, owingto losses which occur at various stagm24Attention may be called to a useful paper in which a largenumber of reactions are described, which serve to distinguishbetween perborates, percarbonates, persulphates, perchlorates, andperiodates.25Among new microchemical reactions one may instance the useof dimethylaminobenzeneazobenzenesulphonic acid as a reagent fornickel and cobalt, the shape and size of the crystals of thenickel salt differing greatly from those of the cobalt salt formedunder the same conditions.26 Further notes have been publishedon the czsium alum test for aluminium,27 and on the use ofammonium uranyl acetate as a microchemical reagent for sodium,2*which render these tests more delicate and certain.2o A.Strihler and F. Bachran, Ber., 1911, 44, 2906; A., ii, 1096.21 P.Koenig, Chcm. Zeit., 1911, 35, 277 ; A., ii, 337.W. C. Ball, Proc., 1910, 27, 329.ZH H. Weil, Bull. SOC, chim., 1911, [iv] 9, 20 ; A., ii, 158.L. J. Curtman and E. Frankel, J. Arner. Chem. Xoc., 1911, 33, 721 ; A., ii, 659.25 W. Lcnz and E. Richter, Zeitsch. anal. Chcm., 1911, 50, 537 ; A., ii, 823.M. E. Pozzi-Escot, Bull. S'oc. chim., 1911, [iv], 9, 22.N. Schoorl, Zeitsch. anal. Chem., 1911, 50, 266 ; Chem. WeekbEad, 1911, 8,2e( W. Lenz andN. Schoorl, Zeitsch. anal. Chem.,.1911, 50,.263; Chcm. Wpekbtad,268 ; A., ii, 443.1911, 8, 266 ; A., ii, 439ANALYTICAL CHEMISTRY. 159So far as the quantitative determination of anions is concerned,the year under review has produced no work equal in importanceto that of Allen and Johnston on the exact determination ofsulphate. Formerly regarded as one of the most exact methodsa t the disposal of the analyst, it has been recognised for someyears that the estimation of sulphate as barium sulphate holdssources of error which are quite large, and that the degree ofaccuracy often, but by no means invariably, attained in practicedepends on a partial compensation of errors, opposite in sign.Beyond that, until last year nearly every statement in the litera-ture was misleading, authors appearing to have no other objectin view than the general adoption of their own empirical method.It is now known that $us errors may be entirely avoided, whilstthe sources of the minus ones have been traced, with the resultthat these can be kept low, and accurate corrections made for sucherror as cannot be avoided.The solubility of barium sulphate invery dilute hydrochloric acid is small, and, contrary to manypublished statements, is almost independent of the amount of alkalichloride present. Alkali chloride, present in most sulphate deter-minations and often present in very large amount, is, however, thechief source of error. All barium sulphate precipitates carry downwith them quantities of alkali sulphates. I n the c a e of pureacidulated sulphates, this quantity is not far from 0.5 per cent.,corresponding with an error of 0.35 per cent. if the sulphate bethat of sodium, whilst the error due to this cause may be doubledif alkali chlorides are present in quantity. Barium sulphate, whenprecipitated from aciciulated solutions of alkali sulphates, alwaysoccludes a certain amount.of “ free ” sulphuric acid. High concen-trations of acid increase the amount of sulphuric acid occluded,and alkali chlorides increase it so much that, where they are presentin large amount, it is the chief source of error. All barium sulphateprecipitates cqntain barium chloride. Compewation bethodsdepend on this, but, since the compensating errors are large andtheir exact amount dependent on conditions difficult to controlexcept in routine work on comparatively uniform material, it isfar better, as it is quite easy, to reduce this positive error tonegligible proportions. If the precipitation be made slowly, theprecipitate does not contain more than 0.15 per cent.of bariumchloride, and all but a trace of this is eliminated during ignition,the barium combining with the “free” sulphuric acid alwayspresent in =ore than equivalent quantity. On these observationsan exact method has been worked out for the determination ofsulphate under any conditions. It is a tedious method, involvingthe use of large quantities of material and the subsequent experi160 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.mental determination of certain correction^?^ but for work makingany pretence to scientific accuracy and for commercial referee work,except where some empirical method is specified in the contract,these would seem to be an obligation on the analyst to adopt thismethod, or at least to work with due regard to the facts its authorshave established.During the present year attempts have beenmade, in the light of the above-recorded results, to find a directmethod for the determination of sulphate, which should be generallyapplicable, exact, and require only small and easily determinedcorrections. There appears to be little chance of discovering as1exact method which shall be generally applicable and .require nocorrections, and yet not owe its accuracy to a compensation oferrors. Where, however, the composition of the solution is approxi-mately known-a condition which frequently obtains in practice-recourse may be had to a calibration method. Such a method, yield-ing results accurate to 0.05 per cent., has been worked out.Itdepends on keeping the individual errors as small it9 possible, andcorrecting for these by running a concurrent determination on aknown and approximately equal weight of pure potassium or sodiumsulphate in a medium such that the resulting solution is as nearly aspossible of the same composition as the solution to be analysed.30The distillation methods for the estimation of fluorine beingtedious, a precipitation method sufficiently exact for many purposesis a matter of interest. It depends on the comparative insolubilityof lead chlorofluoride, PbFCl, in water, and itis still more markedinsolubility in solutions of lead chloride. The solubility is not solow a3 could be wished in a compound chosen to serve as the basisof an analytical method, but quantities like 0.03 gram of fluorinec m be determined with an error not exceeding + 1 per cent., andthis without any correction based on the known solubility of theprecipitate in the liquids used for washing or on parallel experi-ments with known quantities of fluoride.An advantage of themethod is the high ratio of the weight of the precipitate to theweight of fluorine estimated.31An interesting method for the estimation of nitrite nitrogendepends on the use of hydrazine sulphate. When excess of thelatter is allowed to act on a solution of any ionised nitrite, nitrogen,nitrous oxide, and ammonia result, in accordance with the followingequation :2NH,*NH, + 3ON.013 = NH, + 2MB0 + N,+ 4HZO.21 E. T. AlIen and J. Johnston, J. Amer.CJmn SOC., 1910, 32, 588; A . , 1910,J. Johnston and L. H. Adams, J. Amer. Chem. Soc., 1911, 33,829 ; A., ii, 766.ii, 650; J. Ind. Eng. Chenz., 1900, 2, 196.31 G. Starck, Zeitsch. anory. Chem., 1911, 70, 173 ; 8.) ii, 436ANALYTICAL CHEMISTRY. 161If the reaction is allowed t o take pIace in a nitrometer, the nitrousoxide may be removed by washing with water, and the residualnitrogen measured. The method has been successfully applied tosome fifty nitrites, including tetramethylammonium nitrite andbenzylamine nitrite, as well as the nitrites of the alkalis, alkaliearths, and heavy metals. On the other hand, amyl nitrite,and in general non-ionised nitrites, do not give rise toany evolution of gas when brought in contact with hydrazinesulp hate.32A method has been described for estimating the activity ofoxidising agentsl by means of the quinonoid imoniurn salts ofbenzidine.If an oxidising agent be added t.0 an excess of anaqueous solution of benzidine, a blue precipitate, insoluble in dilutesaline solutions and sparingly soluble in water, is obtained. Thiscompound is an analogue of the meri-quinonoid salts of diphenclquinonedi-imine described by Schlenk, the negative radicle depend-ing on the particular oxidising agent employed. Since the com-pound retains in the active form the whole of the oxidising powerof the active oxygen employed in its formation, it affords a meansof estimating the oxidising power of solutions obtained in thecourse of physiological investigations and of coloured solutionswhich cannot be titrated direct.The blue compound is filtered off,decomposed with hydrochloric acid, and treated with potassiumiodide, the liberated iodine being subsequently titrated with thi+sulphate. The method has been chiefly used in the invedigationof blood and of peroxydases, and might equally well have foundmention in a later section of this report, but is assigned its presentplace because of the probability that the mechanism of the actionof oxydases, peroxydases, and catalases rests on an inorganicbasis.33A critical investigation of the volumetric methods for the estima-tion of mercury depending on reduction to metal has led to therecommendation of a modification of Feit's method.34 The newmethod surpasses any of its predecessors in accuracy, but, likeFeit's original method, has the disadvantage that the mercury inthe solution to be tested must all be in the mercuric state.Themercury is obtained in globules of such a size that solution ofmercury by iodine is very slow. This makes it possible to avoidfiltration without diminution of accuracy. The accuracy attainableis within 0.05 C.C. of thesolutions used, and is secured by carrying32 B. B. Dey and H. I<. Sen, Zeilsch. anorg. Chem., 1911, 71, 236 ; A . , ii, 822.W. Madelung, Ber., 1911, 44, 626; A., i, 323 ; Zeitsch. physiol. C'hcwz., 1911,71, 204 ; A., i, 411.34 W. Feit, Zeitsch. anal. Chem., 1889, 28, 318 ; A , , 1889, 927.REP.-VOL. VIII. 162 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.out the reduction by means of sodium arsenite in a non-oxidisingatmosphere.35 The method is less rapid than that of Rupp,M andRupp’s method has the advantage that it is applicable to mixturesof mercuric and mercurous salts, which are first reduced to metalby some reducing agent without action on iodine in acid solution,the mercury being then dissolved by excess of standard iodinesolution, and the excess of iodine determined by means of thio-sulphate.As originally described, however, Rupp’s method doesnot yield results of the highest accuracy, and the modifications ofit (for example, that of Muller37) complicate it without notableimprovement in the accuracy of the results.A portion of the copper in burned pyrites obstinately risistssolution by means of nitric acid, but the whole of the copper ineither pyrites or burned pyrites may be obtained in solution suitablefor electrolysis after heating for a few minutes with reduced ironin an ignition tube. The contents of the tube are treated withhydrochloric acid until all the iron is dissolved, and any coppernot already precipitated as sulphide is thrown down by meansof hydrogen sulphide.The insoluble matter is. then collected andwashed, and the copper brought into solution suitable forelectrolysis .3*A method described by Heath for the estimation of arsenic incopper will appeal to too narrow a, circle to justify more thanmere mention here, but there can be no doubt that it surpasses allolder methods in accuracy.39The separate estimation of tin and antimony when occurringtogether in solution ceased to be a difficult operation with theappearance of Low’s method 40 in 1907.The operation of dissolvingtin from its ores appears still to give trouble t o many workers, andfor this reason attention may be directed to two recent notes.41Although the existence of Low’s method deprives new methods forthe estimation of tin and antimony of much of the interest whichwould formerly have attached to them, attention must be calledto m e recent method which is wholly novel and almost as simpleas that of Low. It depends on the fact that, in acid solution, bothstannic and stannous sulphide yield stannic iodide on treatmentwith iodine, whilst. both antimonous and antimonic sulphide yield95 F.Reinthaler, Chern. Zeit., 1911, 35, 593 ; A, ii, 660.36 E. Rupp, Arch. Pharni., 1905, 243, 300 ; A . , 1905, ii, 484.47 J, A. Muller, BUZZ. soc. chim., 1907, [iv], 1, 1169 ; A . , 1908, ii, 227.38 W. N. Iwanoff, Chem. Zeit., 1911, 35, 551 ; A . , ii, 660.39 G. L. Heath, J. l n d . Eny. Chem., 1911, 3, 74.4O W. H. Low, J. Amer. Chem. Suc., 1907, 29, 66 ; A., 1907, ii, 304.41 H. Y. Loram, Proc., 1911, 27, 60 ; A. Gilbert, Zeitsch. ofentl. Chenz., 1910,16, I44 ; A., ii, 71ANALYTICAL CHEMISTRY. 163antimonous iodide, the whole of the sulphur separating as such ifiodine is present in excess.42For the estimation of chromium in steels which also containtungsten, the most accurate method is that of von Knorret3 butit is somewhat tedious, and calls for the continuous attention ofan experienced operator.Means have been found to simplify itso that the analysis may be completed ip less than two hours, anadvantage which may in many cases outweigh the slight decreasein the accuracy of the results.44 The reaction of chromates withdisodium 1 : 8-dihydroxynaphthalene-3 : 6-disulphonate, referred toamong qualitative reactions, may be made the basis of a colorimetricmethod for the estimation of extremely minute quantities ofclixomium.4~Although manganese is usually estimated by volumetric methodst o day, a paper which lays down the conditions under whichMnO, Mnz03, or Mn,O, can be completely converted into either ofthe other oxides must be regarded as important.46 With so manygood methods available for the estimation of manganese, no greatimportance attaches to a new one, unless the authors are right inthinking that for certain steels i t gives results slightly more accuratethan those obtained by other methods. It depends on the factthat, in presence of sufficient hydrofluoric acid, manganese reactsquantitatively with permanganate, all the manganese after thereaction being in the tervalent form.47Several papers have appeared during the year on the estimationof small quantities of lime in presence of much magnesia, but themethod of Murmann remains the only satisfactory method wherethe magnesia-lime ratio exceeds 50:l.The method depends onthe insolubility of calcium sulphate in 90 per cent. alcohol, andjudged from some abstracts of the paper might appear indistinguish-able from a method t o be found in many text-books.Reference tothe original, however, will show that this is no purpmeless modi-fi~ation.~* The same author has worked out a simpler method, whichgives results sufficiently accurate for many technical purposes whenthe magnesia-lime ratio is less than that stated. Essentially itconsists in the substitution of quinoline for ammonia in the ordinaryoxalate precipitation.4942 J. C. Beneker, J. Ind. Eng. Chem., 1911, 3, 637.43 G. v. Knorre, Stahl 16 Xiscn, 1907, 27, 1251.H. Wdowiszewski, Chem. Zeit., 1910, 34, 1365 ; A., ii, 157.P. Koenig, loc. cit., and Landw. Jahrb., 1910, 39, 775 ; A . , ii, 524.46 P. N. Raikow and P. Tischkoff, Chew Zeit., 1911, 35, 1013; A., ii, 936.47 F.J. Metzger and L. E. Marrs, J. ImZ. Eng. Chem., 1911, 3, 333.48 E. Miirmann, Zeitsch. anal. Chenz., 1910, 49, 688 ; A . , 1910, ii, 897.4g E. RIurmann, Monatsh., 1911, 32, 105; A., ii, 440.M 164 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,Rawson’s method for the separation of strontium from calcium 50has been finally discredited, and the opinion expressed that theether-alcohol method alone of existing methods has any claim toexa~tness.~~ Many will endorse this view, but almost simultane-ously a method was described which depends on the insolubilityof strontium chromate in 50 per cent. alcohol. If this methodproves sound, i t will become important, as i t forms part of a methodfor the separation of barium, strontium, and calcium which iscapable of a volumetric modification.5z A method has been describedfor the separation of barium from calcium and magnesium by theaction of acetyl chloride and acetone on the mixed chlorides.53Following up the work of Rothe, whose process for the etherseparation of irons4 from other metals has proved so valuable inwcrking out methods for the analysis of special steels, Mylius andHuttner have studied the behaviour of thirteen metallic chlorideswhen shaken with ether and water or with ether and hydrochloricacid of varying strength.55 The immediate result of this researchis the elaboration of a new wet method for the assay of goldbullion.Four or five extractions with ether suffice to obtain resultsaccurate to 1 per mille.For the most exact work of a mint, theether process is made use of to separate the bulk of the gold fromall the other metals. These and traces of gold are then recoveredfrom the acid-aqueous solution by the usual methods. The methoddiminishes the tediousness of a complete analysis of gold bullion,and in point of accuracy cannot be excelled, but its practical valuedepends perhaps more on the fact that it affords the most readymeans of preparing normal gold of the highest grade of purity.56The iodic acid method for the separation of thorium57 has beenfurther studied, as well a,s the conditions which determine itssuccessful application to the detection of traces of thorium inpresence of much cerium. I n its improved form the method affordsa means of separating scandium from thorium.58A method has been described for the separation of columbium,tantalum, titanium, and tungsten from the rare earth metals which50 C.Rawson, J. Soc. Chan7. Ind., 1897, 16, 113.61 L. Moser and L. Machieclo, Chem. Zeit., 1911, 35, 337 ; A., ii, 439.62 J. L. M. van der Horn van den Bos, Chem. Wcekblad, 1911, 8, 5 ; A., ii, 228.63 F. A. Gooch and C . N. Boynton, Zeitsch. anorg. Chem., 1911, 70, 400 ; A.,ti4 T. W. Rothe, ilfitt. d. Kgl. Techn. Vtmuchsamt., 1892, 132.55 F. Mylius and C . Huttner, Ber., 1911, 4, 1315 j A . , ii, 540.66 F. Mylius, Zeitsch. anorg. Chem., 1911, 70, 203 ; A . , ii, 444.67 R. J. Meyer and M. Speter, Chem. Zeit.: 1910, 341, 306 ; A., 1910, ii,b8 R. J. Meyer, Zeilsch.anorg. CJbem., 1911, 71, 65 ; A , , ii, 825.ii, 334.459ANALYTICAL CHEMISTRY. 165depends on the fact that the former may be volatilised as chloridesin a current of sulphur mono~hloride.~~It has been shown that the uncertain end-point in the titrationof ferrous iron in silicate rocks after decomposition of the rockby means of hydrofluoric and sulphuric acids is unconnected withthe presence of manganese, and that the usual precautions fail tomake the end-point even reasonably sharp with some rocks. Theserocks were in every case found to contain notable proportions oftitanium, but titanium dioxide, even in large amount, has nodisturbing effect on the titration. Addition of titanous acid,however, to a ferrous solution before titration with permanganate,leads, as might be expected, to indefinite end-points similar to thoseoccasionally observed in the course of rock analysis. It is suggestedthat, rocks may contain titanium as Ti,O,, as well as in one or otherof the crystalline modifications of the dioxide.This view is con-firmed by the f a c t that sharp end-reactions may be obtained by theaddition to the titration liquid of excess of finely divided silicaand a considerable amount of potassium sulphate. Ferric salts arebut slowly reduced by titanous acid in hydrofluosilicic acid solution,and high saline concentrations also tend t o retard the reaction.60It is now generally recognised that the exact determination ofvanadium, especially in chrome vanadium steels, is a far less easyoperation than might be supposed on reference to papers not manyyears old.Methods requiring the use of ferricyanide as indicatorfor ferrous salts, where quadrivalent vanadium and ferric salts areslso present, must of necessity be very uncertain. An error in allmethods where final titration is made against permanganate mayarise by failure to deduct the blank due to elements other thanvanadium. This error may amount to 100 per cent. in the case ofproducts of low vanadium content. The temperature of titrationis also important. I n methods in which iron is removed by etherextraction, ferrous salts are apt to be formed, and must bere-oxidised. If the evaporation of a solution of quadrivalent vana-dium with concentrated sulphuric acid, to eliminate hydrogenchloride, is too prolonged or conducted a t too high a temperature,oxidation may occur.61 I n methods in which, after an etherseparation, the remainder of the iron, as well as any chromium, istQ be separated from vanadium by pouring into a boiling solutionof alkali hydroxide, there are several sources of possible error.Vanadium is almost always carried down with the hydroxides ofiron and chromium, and two or three precipitations are necessary.69 W.B Hicks, J. Amer. Chem. SOC., 1911, 33, 1492 ; A., ii, 567.6o M. Dittrich, Chem. Zeit., 1911, 35, 1093 ; compare A . , ii, 543.E. Muller and 0. Diefenthaler, Zeitsch. anorg. Chem., 1911, 71, 243 ; A., ii, 824166 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY..Another source of error is due to manganese, which tends to becomeoxidised to peroxide during the boiling with alkali hydroxide, andthis peroxide oxidises chromium salts to chromate. Som!, but notall, of these errors are avoidable, and it will be apparent thatagreement between laboratories using different methods mustdepeiid in large measure on the exchange of “ analysed samples.”Such ‘‘ analysed samples,’’ especially when they can be obtainedby everyone, as in the case of those issued by the United S’tatesBureau of Standards, are useful, but they are a poor substitutefor an exact method.An exact method appears now to be availableto those who possess electrolytic appliances. Vanadium andchromium are precipitated together with a, little iron by adding alarge excess of cadmium carbonate to the boiling acid solution.The precipitate is dissolved in acid, freed from cadmium by meansof hydrogen sulphide, and the filtrate electrolysed, using a mercurycathode, until free from iron and chromium.I n the exhaustedelectrolyte the determination of vanadium is easy.62The tendency of precipitates of ferric hydroxide to carry downvanadium, referred to above as a fertile source of error in deter-minations of vanadium, is actually made use of in one recentlydescribed method. The method is available in presence ofchromium, but it is a colorimetric method, and therefore of limitedaccuracy, and it requires the preparation of standards containingapproximately the same amount of iron and acid as the solutionunder examination.63A new, rapid, and accurate method for the volumetric estimationof molybdenum, depending on its reduction by zinc and hydrechlorilc acid and the subsequent oxidation of the reduced solutionwith standard methylene-blue, is deserving of notice, but it is notapplicable to the analysis of steels containing titanium, tungsten,chromium, or vanadium.64 As our knowledge grows, the choice ofmethods for the determination of molybdenum in actual practicetends t o decrease; for example, molybdenum glance now comes intothe market containing notable amounts of magnesium, copper, andzinc, nearly the whole of which may get weighed as MOO, when thematerial is analysed in accordance with the directions to be foundin some recent text-books.For such material the method ofTrautmann 65 appears the only one available, and all but experienced62 J.R. Gain, J. Ind. Eng. Chcm., 1911, 3, 476.E3 C. R. M’Cabe, Chcna. Engineer, 1911, 13, 243 ; Chcm. Ncws, 1911, 104, 194,202.E. Xnecht and F. W. Atacli, Analyst, 1911, 36, 98 ; A., ii, 337.65 W. Trautmaxin, Chcm. Zcit., 1909, 33, 1106 ; A , , 1909, ii, 942 ; Zeitsch.miyew. CheTn., 1911, 24, 207 ; A . , ii, 230ANALYTICAL CHEMISTRY. 167workers will do well to weigh finally as^ MoS,, as suggested byCollett and Eckardt.66Several methods are available for the accurate determination oftungsten in wolfram concentrate, and useful notes on each havebeen published within the year.67 A volumetric method applicableto the analysis of commercial tungstic acid and to lamp filamentshas also been dexribed.68 The authors of the latter claim thattheir method is available for the rapid and exact determination oftungsten in steel, but give no test numbers for a chrome-tungstensteel.I f the method proves accurate for chrome-tungsten steel, itwill assume considerable importance for the best existing method-von Knorre’s benzidine method 69-cannot be described as morethan fairly satisf actory.70The use of alloys of tungsten, molybdenum, vanadium, etc., bysteel-makers has not only necessitated a strict re-investigation ofmethods for the estimation of these elements, but has also consider-ably complicated the determination of carbon, sulphur, and phos-phorus in steel and steel-works materials. As examples only ofwork in this direction, attention may be called to the recent state-ments that, in high-grade alloys of tungsten, molybdenum, orvanadium with iron, carbon and sulphur can be determined accu-rately only by direct dry combustion71; that, in ferrotitauiumalloys containing much silicon, carbon cannot be determinedaccurately by direct combustion unless the alloy be first decompmedin a current of chlorine72; and to a, paper on the estimation ofphosphorus in tungsten stee1.73It has been proposed to make use of sodium thiosulphate it5standard in alkalimetry. The proposal rests on the fact that whenexcess of mercuric chloride is allowed to a c t on thiosulphate, twomolecules of hydrogen chloride are set free by each molecule ofthiosulphate present.74E.Collett and M. Eckartlt, Chem. Zczt., 1909, 33, 968 ; A . , 1909, ii, 941.E. Ihecht and JZiss E. Hibbert, ibid., 96.67 H. W. Hutchin, Analyst, 1911, 36, 398 ; A . , ii, 940.69 G . v. Knorre, Zeitsch. anal. Chew, 1908, 47, 337 ; A , , 1908, ii, $79.$0 fi’. W. Hinrichsen and T. Dieckmann, Mitt. K. ~ ~ a t e r i a l p r u f u r ~ ~ s a ~ ~ t Gross-7l E. Miiller and B. Diethelm, Zeitsch. angcw. Chem., 1910, 23, 2114 ; A . , 1910,Liehtcrfeldc lVd, 1910, 28, 229,; A,, ii, 156.ii, 1110.W. Trautmann, ibid., 1911, 24, 877 ; A , , ii, 661.73 F. W. Hinrichsen, 7 t h Ixdern. Cony-. App. ch~?lZ., 1909, I, 116.74 TV. Feld, Zeitsch. anyezo. Chew,., 1911, 29, 1161 ; A , , ii, 769168 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Electrochemical Analysis.Whilst much careful and useful work is accomplished each year,so far as the determination of metals is concerned, the advanceto be recorded is mainly one of detail, which can find no noticehere.The work of Stoddard75 with the mercury cathode andstationary anode, however, seemed to herald a reaction towardssimpler forms of apparatus. Benner and others have not onlyconfirmed the work of St~ddard,'~ but have shown that rapid andaccurate work can be accomplished by means of a stationary anodeand gauze cathode.77 Other proposals to dispense with mechanicalagitation depend on the use of special but simple apparatus.According to one of these proposals, the electrolyte is agitated bymeans of a current of gas,7* whilst, according to another, agitationis effected by the gas evolved during electrolysis, the volume of thisgas being made sufficient for the purpose by working underdiminished pressure.79 If attention is directed to work of this kindrather than to work of the type represented by a paper of Sand,soi t is because work of the latter kind will necessarily be read byall who are actually engaged in electrochemical analysis, whilst aperusal of the papers quoted may cause some to reconsider anaversion to electrochemical methods engendered by the increasingcomplexity of the apparatus recommended in recent years.Where i t can be shown that results of the highest order ofaccuracy cannot be obtained by simpler means, no amount ofcomplexity is unreasonable. As an example of what electroanalysisis capable of, when there is no restriction on complexity ofapparatus or quantity of material to be taken for analysis, referencemay be made to a paper on the exact electrolytic assay of refinedcopper.The estimation of the acidity of tan liquors is rendered difficultby their dark colour, which tecds to mask the colour change ofordinary indicators.The electrometric method, based on thedetermination of the difference of potential between the liquidunder examination and a plate of platinised platinum saturatedwith hydrogen, was formerly more or less impracticable owing toThe results are accurate to 0.01 per cent.*'75 J. Stoddard, Ann. Report, 1910, 170 ; R. C. Renner, ibid.76 R. C. Benner and L. M. Hartmann, J.Amer. Chem. Soc., 1910,32, 1628 ; A.,77 R. C. Hennsr and W. H. ROSS, ibid., 1911, 3 3 , 493, 1106 ; A., ii, 443, 770.F. Fisher, C. Thiele, and E. Stecher, Zeitsch. Elektruchem., 1911, 17, 905ii, 148.d.,ii, 1129.79 Ibid., 906 ; A., ii, 1129.8o H. J. 5. Sand, Chew,. News, 1911, 103, 1 4 .a1 G. L. Heath, J. Ind. Eng. Chcm., 1911, 3, 74ANALYTICAL CHEMISTRY. 169complication of apparatus. Recently, however, the apparatus forsuch purposes has been so much improved for the purpose of theelectro-analytical separation o'f metals 82 that its application is nowan exceedingly simple matter, and two important papers on theestimation of the acidity of tan liquors by t,he electrometric methodhave been read and discussed within the year. The indications ofthe electrometric method have a degree of certainty and objective-ness not approached by other methods, but the interpretation ofthe results in terms of direct value to the tanner is a matterwhich now needs and merits research.83Organic Analysis.Few qualitative reactions are sufficiently important to findmention in such a report as this.One depending on the influenceof compounds of a certain type, on the crystalline form of iodoformis, however, interesting. First described some years ag0,84 andsupposed a t o'ne time to be specific for aromatic inner anhydrides,85it is now known that i t is given by aromatic hydroxy-acids with along side-chain and by polyhydro8xy-ketones, but with a slight modi-fication of the original procedure i t is said that the reaction maystill be accepted as proof of the presence of aromatic inneranhydrides.86A reaction capable of detelcting phenol or salicylic acid in adilution of 1 per million may prove useful on account of itsdelicacy, but, since it depends on the formation of tri-iodophenol,it is scarcely likely to prove ~pecific.8~As regards ultimate analysis, it has been pointed out that cobaltoxide has certain advantages over copper oxide, and that metallicnickel, prepared in a particular way, serves well for the reductionof oxides of nitrogen.@ A method has also been described for thesimultaneous estimation of carbon, hydrogen, oxygen, nitrogen,sulphur, and halogenspg whilst a simple and accurate method forthe determination of iodine in certain compounds, which yielderratic results when treated by Carius' method, has been based onthe fa.ct that the organic rnatter is completely oxidised when theb2 H.J. S. Sand, Trans. Fwraday Soc., 1909, 5 , 159.83 H. J. S. Sand and D. J. Law, J. SOC. Chenz. Ind., 1911, 30, 3 ; A., ii, 233.J. T. M700d, H. J. S. Sand, and D. J. Law, ibid., 872 ; A., ii, 942.w R. Bardach, Chem. Zeit., 1909, 33, 570 ; A., 1909, ii, 626.g5 B. Bardach, Zeilsch. anal. Chenz., 1911, 50, 545 ; A . , ii, 826.86 B. Rardach, Chem. Zeit., 1911, 35, 934; A., ii, 945.8' J. M. Wilkie, J. SOC. Chem. Ind., 1911, 30, 402; A., ii, 547.88 A. Kurtenacker, Zeitseh. amd. Chenz., 1911, 50, 548 ; A., ii, 823.89 J. A. A. Auzies, Bull. SOC. chim., 1911, [iv], 9, 815 ; A., ii, 92170 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.substance is treated with permanganate and nitric acid, thechlorine and bromine being converted into volatile products, whilstthe iodine remains as iodic acid.90 The nitrogen in oximes maybe estimated by oxidising these by means of a standard solution offerric chloride, the excess of which is subsequently determinediodometrically.The results are accurate within 0.05 C.C. of thestandard solutions wed.91Some years ago Sudborough and Hibbert outlined a generalmethod for the quantitative estimation of amines, based on themeasurement of the volume of methane evolved when these sub-stances are caused to react with magnesium methyl iodide.92 Theyalso employed a similar method for estimating hydroxyl compounds,and obtained satisfactory results in most ca~es.~3 Zerewitinoffsubsequently showed that this method could be used for the mostvaried types of hydroxy-derivatives, and also for estimating thereactive hydrogen in other groups of compounds, for example,hydrosulphides, imides, and amides.94 At a later date Sudboroughand Hibbert were able t o show that their original method wascapable of general application, not only for the estimation ofprimary and secondary amines, but also for the quantitative deter-mination of mixtures of these with tertiary amine~.~5 Zerewitinoff,having shown that the method is of service, even in the case ofsuch complicated compounds as sugar and flavone, has nowextended it to the alkaloids-derivatives of tertiary amines.Thesereact with magnesium methyl iodide in pyridine solution if theycontain hydroxyl groups, and the results at the ordinary tempera-ture are practically identical with those obtained on heating to85O; this is regarded as evidence that they contain no amino-group,since, as a, rule, aminegoups only react with one hydrogen at theordinary temperature, but on heating the mixture to 8 5 O thesecond hydrogen atom reacts quantitatively. Certain tautomericcompounds, containing the group CO-CH,, which is capable ofassuming the form C(OH):CH, yield results below the theoreticalunless the reactions be conducted a t a temperature approximatinglooo. Similarly, primary and sepndary nitro-compounds of thealiphatic series are capable of assuming a pseudo-acid form, inA.F. Seeker and W. E. Mathewson, U.X. Dept. of Agric., Bzereau of Chem.,Y1 R. Fabiiiyi, ith Intern. Cmgr. Appl. Chesz., 1909, IVY A l , 171 ; A.;Circular No. 65.ii, 534..T. J. Sudborough and H. Hibbert, Proc., 1904, 20, 165.93 J. J. Sudborongh arid H. Hibbert, Trms., 1904, 85, 933.94 T. Zerewitinoff, Ber., 1907,40, 2023 ; 1908, 41, 2233 ; A., 1907, ii, 509 ; 1908,96 J. J. Sudborough and H. Hibbert, Trans., 1909, 95, 477.i, 593ANALYTICAL CHEMISTRY. 1710 which they form salts in virtue of the labile group R*CH:NqOH,which reacts with magnesium methyl iodide. These also giveresults below the theoretical at the ordinary temperature, and thereaction is not quite complete even at lOOO.96 A recent proposalto use magnesium ethyl iodide and to determine the evolution ofethane by loss of weight,*7 instead of by direct measurement, mayprove serviceable in special circumstances, but the originalvolumetric method owes its importance largely to its rapidity andthe fact that only small quantities of substance are required.Following Fischer and Freudenberg’s observations on the proper-ties of ca.rbalkyloxy-derivatives of tannins?8 Daniel and Nierensteinhave based a method for the estimation of hydroxyl groups insubstances of the tannin class on the saponification of these deriv-atives, the preJparation of which offers the advantage that intra-molecular changes and splitting up of the sensitive tannincompounds are apparently excluded. The saponification takes placeaccording to the equation:R*O=CO,R’ + H,O = R*OH + CO, + R’*OH,and the quantitative estimation consists in weighing the carbondioxide split off.99The reaction of enolic compounds with ferric chloride plays animportant part in the study of cases of desmotropy for the detec-tion of the 2oint at which the ketonic form begins t o change intothe enolic form.By the use of suitable standards and a colorimeter,this reaction may be employed in a quantitative sense for the studyof the equilibria at different temperatures and in differentsolvents. The maximum colour intensity is attained when1 molecule of ferric chloride reacts with 1 molecule of the enol.A convenient standard is obtained by mixing a solution of the pureenolic form with an eyuimolecular quantity of dry ferric chloride.This solution is cosmpared with an equally concentrated solutionof the enol-ketone mixture to be examined containing the samequantity of ferric chloride a,s the standard solution.In some caseswhere the enolic form cannot be obtained in the pure state or isinsufficiently stable in solution, standards are prepared from thereadily iso1atc.d ferric snol salts of the general formula, FeR,, whichgive maximum colorations when mixed with 2 moleculm of ferricchloride and 3 molecules of hydrogen chloride. I n certain othercases it is possible to lase as standards stable solutions, in which the9G T. Zerewitiiioff, Bcr., 1910, 43, 3590; A., i, 101.97 B. Oddo, zbid., 1911, 44, 2048; A., ii, 826.‘Js E. Ii’ischer and K.Freudenbcrg, Anncclen, 1910, 372, 32 ; A., 1910, i, 265.99 K. C. R. Daniel and M. Nierenstein, Ber., 1911, 44, 701 ; A, i, 371172 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.equilibrium has been reached and the percentage of enol determinedby one of the other standards.1Of the several organic acids of the aromatic series which havebeen recommended for use as standards in acidimetry, p-aminclo-sulphobenzoicacid appears to be the most suitable for the purpose.It is a well-defined substance, elasily prepared in a pure condition,and as it is anhydrous it can be thoroughly dried in any convenientmanner without risk of alteration in composition. The endreaction on titration with phenolphthalein is sharp, and the quantityof sodium hydroxide required for neutralisation coincides so closelywith the theoretical quantity as to meet the most exact requirementsof volumetric analysis.2The use of titanium trichloride in volumetric analysis first sug-gested by Knecht and Miss Hibbert for the titration of azo- andnit.ro-compounds,3 and referred t o in previous report^,^ has beenextended to the estimation of quinones.5A method is now available for the estimation of small quantitiesof acetic anhydride in acetic acid.It depends on the fact that2 : 4-dichloroaniline reacts rapidly with acetic anhydride, but notwith acetic acid at' the ordinary temperature. The resulting anilideis readily and quantitatively converted into a chloroamine, and theaccurate estimation of the latter is extremely easy by reason of itsquantit,ative reaction with hydriodic acid, and the titration of thefree iodine with thiosulphate.6When Jorgensen's method for the differentiation of organicplant acids 7 is applied, aconitic acid is estimated partly as citricand partly as malic a,cid.By the application of a polarimetricmethod for the estimation of malic acids and by other means,Q i t isnow possible to estimate aconitic acid with some approach toaccuracy, even in admixture with many other vegetable acids. Oneof the first results of the application of the new method is theproof that aconitic acid is the preponderant acid in sugar-canejuice.I n 1905, Steineggerlo showed that the protein content of milk1 L. Knorr and H. Schubert, Bcr., 1911, 44, 2752 ; A., i, 948.3 E.Knecht and Miss E. Hibbert, Ber., 1903, 36, 1549 ; A., 1903, ii, 509.5 E. Knecht and Miss E. Hibbert, Ber., 1910, 43, 3455 ; A., ii, 76.6 Miss M. G. Edwards and K. J. P. Orton, Trans., 1911, 99, 1181.7 G. Jijrgensen, Zeitsch. Nahr. Gcnzcssm., 1907, 13, 241 ; A , , 1907, ii, 312.8 P. A. Yoder, J. Ind. Eng. Chcm.. 1911, 3, 563 ; also Zeitsch. A7ahr. Genzcsm,9 P. A. Yoder, J. Ind. Eng. Chem., 1911, 3, 640.10 R. Steineggcr, Zeitsch. Nahr. Genztssm., 1905, 10, 659; A , , 1906, ii, 130.J. H. Kastle, Amer. Chern. J., 1910, 44, 487 ; A., ii, 66.Ann. Report, 1905, 195 ; 1907, 211.1911, 22, 329 ; A., ii, 1141ANALYTICAL CHEMISTRY. 173wasingtheapproximately proportional to the values obtained by neutralis-the milk, adding excess of formaldehyde, and then titratingnow acid solution with alkali hydroxide.He appeared to haveno knowledge of the work of Schiff 11 on discrimination between basicand acidic funtctions in solutions of amino-acids and proteins, andhe termed his titration values the “ aldehyde figure” of the milk,although hf: was not measuring aldehyde, nor measuring anythingelse in terms of formaldehyde, but simply using the latter fo annulthe basic function of the protein molecules so that their carboxylgroups could be titrated. It is now known that Schiff’s reactionis reversible, but means have been found to make the end-point ofthe titration such that the hydrion concentration is as low asunder which conditions the reaction is approximately quantitative,l2 and the method has been widely applied in connexion withphysiological work.13 As applied to the estimation of proteins inmilk, i t is now shown that the method gives results of the sameorder of accuracy as the centrifugal methods for the estimation offat.14 With rare abnormal samples the error is considerable, andwith milk in which bacterial or enzymic action has proceeded fari t must necessarily give results above the truth i f the factor fornormal milk proteins be applied.Unfortunately, the titrationvalues continue t o be called the “aldehyde figure,” an expressionwhich is perplexing to many when they first encounter it, whereas“ aminocacid number ” would be readily intelligibIe, and would alsosuggest the limitations of the method.The cryoscopic method forthe detection of added water in milk15 has been applied to some2500 French samples, and the author concludes that the methodwill distinguish between genuine and watered milks, notwithstan$-ing differences of age, provided a suitable correction, given in thepaper, be made for the lactic acid present. A freezing point above-0’530O is said t o be conclusive evidence of watering, whereas anormal freezing point of -0.55OP should be accepted as proofof genuineness whatever be the results of chemical analysis.16The methods of Ewers and Fendler for the detection of cocoanutoil in butter, referred to in last year’s report 17 as likely to proveuseful, have scarcely fulfilled that expectation,l8 and the Polenskemethod remains the only chemical method by which small quanti-l1 H.Schiff, AnnaZen, 1902, 319, 59, 287 ; 325, 348 ; A . , 1902, i, 85, 250 ;1903, i, 232.l2 Ann. Report, 1908, 205. l8 Ibid., 1910, 181.l4 H. D. Richmond, Analyst, 1911, 36, 9 ; A., ii, 236.I6 L. Stoecklin, Ann. Falsif., 1911, 4, 232.l7 A m . Report, 1910, 177.l8 E. Nockmann, Zcitsck. Nahr. Genussm., 1911, 21, 754 ; A. Hepner, ibid., 758.W. R. G. Atkins, Chem. News, 1908, 97, 241 ; A , , 1908, ii, 641174 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ties of cocoanut oil can be detected and approximately estimated inbutter. Its alleged failure in certain cases can usually be tracedto a disregard to experimental details which are of the essence ofthe process. Kirschner’s extension l9 of the Reichert-Meissl processoffers little value over the Polenske method for cocoanut oil inbutter, but, as the result of an exhaustive research on the subject,t-he opinion has been expressed that it is the only published methoda t present available which will decide whether butter-f at is presentin a margarine containing cocoanut oil, even if the amount be only2 per cent.in conjunction with 75 per cent. or more of cocoanutoi1.20The utility of Fiehe’s test21 for the detection of artificial invertsugar in honey, which depends on the presence of a-hydroxy-6-methylfurfuraldehyde in all artificial invert sugar, continues to findconfirmationY22 and a simplified procedure using a different reagentfrom that employed by Fiehe has been described.23 Reactions char-acteristic of natural honey are of litt*le value f o r the detection ofadulteration unless they can be made quantitative and some‘‘ standard ” agreed on as representing genuine honey. Theseconditions appear to be fulfilled in the case of Langer’s interestingserological test,2* which can be made roughly quantitative, whilstthe quantitative results yielded by the genuine honeys so farexamined lie very close together.25The estimation of nicotine received an unusual amount of atten-tion during 1911.Tobacco extracts are now an important articleof commerce, and the prices of competing brands only differ byabout 10 per cent. from the mean price, whilst the percentage ofnicotine may be anything from 1.5 to 11 per cent.26 I n the interestalike of purchasers and of the more reputable manufacturers, theintroduction of the unit system of payment seems desirable. Thisimplies, however, the existence of one or more accurate methodsfor the estimation of nicotine, or, failing such, an internationalagreement as to the manner in which nicotine is to be estimated.Early in the year the latter course was recommended as the resultof experiments which showed that existing methods gave veryl9 Kirschner, Zeitsch.Nahr. Genumn., 1905, 9, 65 ; A . , 1905, ii, 213.a1 J. Fiehe, Ann. Report, 1910, 174.a G. Curtel, F. Muttelet, and E. Moreau, Ann. Falsif., 1910, 3, 497, 503, 513 ;W. Hartmann, Zeitsch. A-ahr. Genzcssm., 1911, 21, 374 ; H. Luhrig and A. Scholz,ibid., 721.C. Revis and E.R. Bolton, Analyst, 1911, 36, 333.23 E. Feder, Zeitsch. Nahr. Genussm., 1911, 21, 412.24 J. Langer, Ann. Report, 1910, 174.2K J. Thoni, Mitt. Lebensmittelunters. u. Hyg., 1911, 2, 80.26 J. Schroder, Zeitsch. anal. Chew., 1911, 50, 433AN A LY TI C A L C H EM I SI‘R Y . 175variable results.27 The immediate result of this proposal was acrop of papers in defence of old methods and descriptive of newones, and withal so hostile to yet other old ones that for a timeconfusion was rendered worse confounded. The net result,however, appears to be that there is no necessity for the impositionof any one method-always an undesirable proceeding when com-mercial interests can be served without resort t o it. In a recentpaper T6th has shown that his method, into which he has i n t wduced modifications,28 Kissling’s method among the older ones, anda new polarimetric method due to DegraziaFQ yield substantiallyidentical results, provided the extract under examination has notbeen sophisticated by addition of pyridine bases.I n their presenceKissling’s method over-estimates nicotine. The simple method ofUlex is said by many authors to give unduly high resulta, butthere is some doubt whether it has had a fair trial. Although theprinciple of the method has been made use of in many laboratoriesfor years, and has rightly been attributed to Ulex, it appears thatthat author never himself published the details of his method untilthe recent controversy.30I n the absence of any other good method for the determinationof codeine in opium, a new volumetric method which appears tobe accurate is worthy of reference.31 Nishi’s method32 for theestimation of quinine in organic liquids, such as urine, has beensimplified, and found to yield excellent results.It does not distin-guish between quinine and the other common cinchona alkaloids,but may be employed for the estimation of quinine in presence ofcaffeine.33 I n competition for the Hagen-Bucholz prizes of theDeutscher Apotheker Verein, A. Kneip, N. Ney, and F. Reimerseach investigated some twenty methods for the estimation ofcantharidin in cantharides and its tincture. Only one of the com-petitors recommends a method which can be described as new, buttheir results are valuable, and rendered more so by the fact thatthey are presented together in a single critical memoir by Emde.34Since the value of turpentine in practice depends on the rapiditywith which it absorbs oxygen, some interest attaches to a recentpaper, in which it is proposed to determine the relative value ofdifferent samples from this point of view, the method describedn J.Schriider, Chem. Zeit., 1911, 35, 30; A . , ii, 163.28 J . Tdth, abid., 926 ; A., ii, 943.29 J. voii Degrazia, Fach. Mitt. b’stcrr. Tabakregie, 1910, 149 ; A , , ii, 671.30 H. Ulex, Chem. &it., 1911, 35, 121 ; A . , ii, 344.31 A . E. Andrews, A?~nlysl, 1911, 36, 489; A , , ii, 1144.32 M. Nishi, Arch. e q . Path. Pharm., 1909, 60, 312; A., 1910, ii, 710.33 T. Cockburn and J. W. Blac’:, A?~fl.Z!jsL, 1911, 36, 396 ; A ., ii, 944.34 H. Emde, Arch. Pharm., 1911, 249, 259 ; A., ii, 669176 ANNUAL HEPORTS ON THE PROGRESS OF CHEMISTRY.depending on the oxidation of cymyl mercaptan by the peroxideformed in the turpentine.35The large number of abstracts appearing in this year's Journalon the direct estimation of caoutchouc in raw rubber by chemicalmethods may lead to the expectation of a somewhat extendedparagraph on the subject in this report, but in the writer's opinioni t is too early yet to attempt Lo cotllate the results obtained, whichin the present state of our knowledge appear irreconcilable. Byfar the greater number of papers are concerned with modificationsof the tetrabromide method,36 and this may perhaps be taken asevidence that a majority of those mmt interested think that thesolution of the problem is most likely to be found in this direction.I n support of this view are the facts that the composition of thetetrabromide is beyond question, and that it is sufficiently insolubleto serve as the basis of an analytical process.On the other hand,the conflicting results obtained by different workers under condi-tions supposed to be identical show that the conditions essentialfor the quantitative conversion of caoutchouc into the tetrabromidehave yet to be determined. I n these circumstances the proposal toextend the use of the method t o vulcanised articles seems prema-ture, and i t has been shown that it' may lead to ridiculous results.37The nitrosite method 38 finds fewer critics, but few supporters.Onemodification of i t may be noted,39 as it is said to give results inclose agreement with those yielded by the method, much in use,according to which caoutchouc is estimated by evaporation of thefiltered solution of the resin-free rubber. There is doubt, however,whether the so-called " nitrosite " has the composition assignedto i t by Harries, and some evidence that the results obtained bythe method depend for their accuracy on a compensation oferrors.40The valuation of crude glycerol has in recent years assumedgreater commercial importance owing to the increased value of thecommodity. The want of uniformity in the methods of analysis,together with the irregularity of the results obtained, emphasisedthe desirability for the standardisation of crude glycerol analysis,and with this object in view committees were formed in America,France, Germany, and Great Britain.These committees workedin the first place independently, but were ultimately broughttogether, and after a series of conferences a unanimous report was35 P. Klason, Chem. Zeit., 1911, 35, 537 ; A . , ii, 665.T. Budde, Ann. Report, 1907, 214.37 W. Esch, Chem. Zeit., 1911, 35, 971 ; A . , ii, 946.38 P. Alexander, Ann. Report, 1907, 214.39 0. Korneck, Gunmi-Zed., 1910, 25, 4, 42, 77); A , , ii, 545.40 P. Alexander, Zeitsch. angew. Chent., 1911, 24, 680 ; A., i, 389ANALYTICAL CHEMISTRY. 177agreed on. The methods detailed i a this report are stronglyrecommended as International Standards.41Agricultural Analysis.A paper which shows that the unavoidable error in samplingsoils is of the order of 5 per cent.t2 somewhat discounts the valueof refined analytical methods in soil analysis.I n one determirwtion, however, namely, that of humus, the uncertainty of theanalytical results has hitherto been far greater than this, and itis gratifying to be able to record the fact that a simple methodhas now been devised which reduces this uncertainty to very smalldimensions.43The products of the new processes for the fixation of atmmphericnitrogen having now reached the markets in considerable quanti-ties, means for their accurate analysis assume some importance, andthe past year hasl witnessed the appearance of a number of paperswhich, read together, appear to place this subject on a fairlysatisfactory footing, although there is not yet that exact accordbetween authors which Commercial interests might wish t o seeestablished.The analysis of calcium cyanamide, which appears incommerce in two distinct forms, distinguished in Germany by thenames " Stickstoffkalk )) and " Kalkstickstoff " (the former contain-ing calcium chloride), has necessarily engaged the attention ofCar0 and his collaborators. They have worked out a method forthe separate estimation of dicyanodiamide and carbamide, presentin small quantity in all commercial samples of calcium cyanamideand in larger quantity in samples which have been long stored, andthey show that the cyanamide can be estimated accurately byprecipitation with an ammoniacal solution of silver acetate anddetermination of the nitrogen in the washed precipitate byKjeldahl's method.The precipitate contains an amount of silverwhich varies with the conditions of the precipitation, but the wholeof the cyanamide is thrown down.44 The statement of Kappen45that i t is easy to secure a precipitate having the composition repre-sented by the formula CNoNAg,, must be received with caution,as, although his figures show that his precipitates closely approxi-mated this composition, his general statement conflicts, not onlywith that of Caro, but with that of at least two other authors.46, 4741 Hehner and others, Analyst, 1911, 36, 314.42 E. A. Mitscherlich and E. Merres, Landw.Jnhrb., 1910, 39, 345 ; A,, ii, 68.43 J. B. Rather, J. Tnd. Eng. Chem., 1911, 3, 660.44 N. Caro and others, Zeitsch. nngew. Chem., 1910, 23, 2407 ; A., i, 119.45 H. Kappen, Chem. Zeit., 1911, 35, 950 ; A., ii, 933.46 R. Monnier, ibid., 601 ; A., ii, 668.REP.-VOL. VIII. N47 A. Stutzer, ibid., 694 ; A., ii, 7771’78 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Kappen makes use of a slight modification of the first method48ever proposed for the estimation of cyanamide, and, after whathas been said, reference must be given to his first and detaileddescription of it.49 I n principle it depends on the precipitation ofcyanamide by a measured excess of an ammoniacal solution ofsilver nitrate of known strength, and titration of the excess ofsilver by means of thiocyanate.A statement has been repeated inmany journals to the effect that Caro’s method fails to estimatethe whole of the cyanamide, and that this failure appears to bedue to silver cyanamide being insufficiently insoluble to afford anaccurate basis on which to found an analytical process. An exam-ination of the original paper 60 in which the statement was firstmade shows, however, that its author, although he quotes Caro,did not use the latter’s method, but determined the silver insteadof the nitrogen in the precipitate.Of more importance, perhaps, from a commercial point of view,is the estimation of the total nitrogen in these new fertilisers. Itmight be expected that this would present no special difficulty, buta survey of the literature affords evidence to the contrary.It hasbeen variously stated that commercial calcium cyanamide does notyield all its nitrogen as ammonia when subjected to the Kjeldahlprocess unless salicylic acid and zinc dust or other reducingsubstamce are present,s1 that the unmodified Kjeldahl process givesaccurate re~ults,5~ and that neither process yields the whole of thenitrogen as ammonia. A t the date of this report the last wordrests with an author who adduces strong evidence to show thataccurate results may be obtained by the use of sulphuric aciddiluted with an equal bulk of water.53The analysis of Norwegian nitre, which is essentially a mixtureof calcium nitrate and hydroxide, with it variable but nevernegligible proportion of nitrite, presents fewer difficulties.Diffi-culty was formerly experienced in determining the moisturecontent, but this has been overcome in a simple manner.54 Theestimation of nitrite presents no difficulty, and the total nitrogenis readily estimated by reduction to ammonia by means of“ Devarda metal,” or may be determined by means of ‘‘ nitron ”after oxidation of the nitrite by permanganate. Experiments haveshown that oxidation of the nitrite by means of hydrogen peroxideis never quantitative, nor is it practicable to attempt the decom-a R. Porotti, Gazzetta, 1905, 35, ii, 228; A., 1905, ii, 870.4n H. Kappen, Landw. Versuchs.-Stat., 1909, 70, 445 ; A . , 1909, ii, 609.50 R. Monnier, Zoc. cit.51 Ibid., Zoc. cit.61 E. Dinslage, Chem. Zeit., 1911, 35, 1045 ; A ., ii, 1027.li4 Dinslage, Zoc. cit.52 Stutzer, loc. cit., and Kappen, Zoc. citANALYTICAL CHEMISTRY. 179position of the nitrite by means of hydrazine sulphate as a pre-liminary to a direct determination of nitrate, as such decompositionis never complete.5j The latter observations have significancebeyond the narrow limits of the subject under which the paper isindexed.Ph ysiolo yical.Van Slyke has further developed his modification of the Sachsse-Kormann method for the estimation of aliphatic amino-gro~ps,~~and his more recent papers57 are so detailed as to be intelligiblewhen read alone without reference to the earlier literature of thesubject. Every known aminsacid reacts quantitatively with one,and only one, nitrogen atom, except lysine, which reacts withtwo, and proline and oxyproline, which do not react at all.Onthis last fact has been founded an accurate method for the estima-tion of proline in admixture with other amino-acids.58 The factthat the copper salts of aminocacids separate copper hydroxide onboiling with alkali, whilst the copper compounds of peptones andpeptides are not decomposed on such treatment, may be made toserve for the detection of aminocacids among the products ofprotein hydrolysis, and for the study of the quantitat.ive relation-ships which exist between the nitrogenous substances of greater orless complexity a t successive stages in an experiment with proteo-clastic enzymes.59 The use of triketohydrindene hydrate for thedetection of proteins and their derivatives 60 has been further investi-gated.The reagent gives a blue coloration with a-aminsacids,polypeptides, peptones, and proteins, with certain exceptions, whichsuggest that the reaction is characteristic of compounds which haveboth a free mino-group and a free carboxyl group. The reactionis one of great sensitiveness, glycine and alanine being detectableby means of it even in dilutions of 1 : 10,000.61The writer of the last annual report made complaint of theunnecessary multiplication of analytical methods by physiologists,62and the last year affords a striking instance of this. Of the so-calledmethods for the detection of adrenaline,63 those depending on thecolour developed on treatment with iodine, mercuric chloride, and56 A.Stutzer and Goy, Chem. Zeit., 1911, 35, 891 ; A., ii, 933.56 Ann. .Report, 1910, 181.57 D. D. van Slyke, J. Biol, Chem., 1911, 9, 185; 10, 15 ; A . , ii, 779, 944.5* Ibid., 205 ; A., ii, 780.69 P. A. Kober, ibid., 1911, 10, 9 ; A., i, 824.S. Ruhemann, Trans., 1910, 97, 2025.E. Abderhalden and H. Schmidt, Zeitsch. physiol. Chem., 1911, 72, 37 ; A.,ii, 674.62 Ann. Report, 1910, 157. 6J ]bid., 1909, 155.N 180 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.iodic acid respectively have been shown to be substantially identical,that is to say, the reagent in each case acts as oxidising agent.A new reaction, said to be somewhat more sensitive than thosepreviously described, depends on the use of potassium persulphate,and the reaction in this case is known to be one of oxidation.64 Itis to be noted that several of the other reagents, suggested fromtime to time for the detection of adrenaline, are capable of func-tioning as oxidisers, but whether this is their r6le in the adrenalinetest remains to be determined. Nearly all these colour reactionsare given by other closely related compounds, and although it isclaimed for some that they are specific, such claims must be receivedwith caution. Now that i t is known that many of them dependon oxidation, systematic experiment with more or less powerfuloxidising agents might result in making the test more specific a tsome expense of sensitiveness, as has been done with the methodsfor the detection of methyl alcohol in presence of ethyl alcohol byoxidation of the former to formaldehyde.It has been found that the presence of hzemoglobin in urinecannot be detected by means of the absorption spectrum unless theurine is quite fresh, and there is some evidence that this is dueto destruction of the hzmoglobin by hippuric acid. Whether orno this is the true explanation of the disappearance of the char-acteristic absorption bands, the research has led to the observationthat by the simple expedient of adding a slight excess of ammoniato a sample of urine immediately after collection, it may bepreserved for a reasonable time in a state fit for spectroscopice~amination.~5 For the direct estimation of creatine in pathologi-cal urine, a method has been described which depends on the factthat diacetyl reacts with creatine, but not with creatinine.66 Thedetermination of lecithin should be rendered more certain by thework of Cohn, who has investigated the conditions governing theextraction of lecithin from substances containing it.67I n ano'ther section of this report attention has been called tothe use of a serological method for the identification of honey, andfor its approximate estimation in admixture with other substances.By the intravenous injection of ricin into rabbits, an anti-ricinserum has been prepared which serves as a precipitation reagentfor the detection of the poisonous constituents of castor seeds incattle foods,6* and a method dependent on the same principle hasbeen used for identifying various kinds of flesh, for example, horse-64 A. J. Ewiiis, J. Physiol., 1910, 40, 316 ; A . , 1910, ii, 557.65 F. A. McDermott, J. Amer. Chem. SOC., 1911, 33, 992 ; A . , ii, 674.66 G. S . Walpole, J. Physiol., 1911, 42, 301 ; A., ii, 671.67 R. Cohn, Zeitsch. ofentl. Chem., 1911, 17, 203 ; A., ii, 779.6@ W. Mooser, Landw. yersuchs-S'tat., 1911, 75, 107ANALYTICAL CHEMISTRY. 181flesh in sausages.69 Certain antiseptics, such as sulphites andformaldehydes, interfere with the latter test, but the interestattaching to these tests depends less on their intrinsic value,although that may prove considerable, than on the expectationthey raise that analytical chemistry will in the near future makemore extended use of similar methods.G. C’ECIL JONES.69 A. Saint-Sernin, Ann. Falsif., 1911, 4, 334

ISSN:0365-6217    

DOI:10.1039/AR9110800153

出版商:RSC    

年代:1911

数据来源: RSC

摘要:

PHYSIOLOGICAL CHEMISTRY.THE year 1911, so far as Physiological Chemistry is concerned, hasbeen one of quiet, uninterrupted progress, but i t cannot be describedas an eventful year. There is no great discovery to be chronicled,and no research or series of researches stands out conspicuouslyamong its fellows.Amongst those who have passed away, one must specially mentionthe names of Dr. Pavy and Professor Christian Bohr.Dr. Pavy was one of those few indefatigable spirits who, likeDr. Ringer, whose lo~sss we had to deplore last year, was able tocarry out important scientific work in the midst of a life of busymedical practice. He is best known as the redoubtable opponent ofClaude Bernard’s views on carbohydrate metabolism, and he con-tinued almost up to the day of his death, at the ripe age of eighty-four, to work a t the subject he had made his own.I n the last fewyears he became interested in the part played by the colourlesscorpuscles of the blood in the transport of substances absorbed fromthe intestine, and his la& paper,l published posthumously, dealswith the power these corpuscles have in incorporating dextrose intheir protoplasm. Pavy’s familiar figure will be much missed inmedical and physiological cir,cles, and the world will be the poorerby his absence.One iittle thought last year when penning the section of the reportdealing with the subject of respiration, that it would be necessarytwelve months later to deplore the loss of Christian Bohr, of Copen-hagen, the leader and inspirer of those researches which haveculminated in our present knowledge of the processes involved inbreathing.Although all of Bohr’s deductions from his experimentshave not been universally accepted, especially in relation to the partplayed by the so-called ‘’ vital factor,” i t cannot be denied that itwas the boldness and novelty of his conceptions that led others totake up the subject afresh, and test them by further experiment.Unlike Pavy, Bohr was a comparatively young man, and his beingF. W. Pavy and W. Godden, “Carbohydrate Metabolism and Glycosuria,”J. Physiol., 1911, 48, 199 ; A,, ii, 1001.18PHYSIOLOGICAL CHEMISTRY. 183suddenly cut off in his prime adds exceptional sadness to the regretat his death which is so universally felt.The year has been singularly destitute of chemical or physiologicalCongresses.The British Association and the British Medical Asso-ciation have had their usual annual meetings with their physielogical sections. I n the case of the latter body, physiology wascombined with anatomy in one section, and the major part of thepapers read were anatomical. The Portsmouth meeting of theBritish Association for the Advancement of Science was a cornpar*tively small one, but was not less interesting on that account. It, infact, often happens that interest and fullness of attendance are ininverse proportion. This was certainly the case with the sectionof Physiology, whilch was opened by a highly speculative addressby the President;, Professor Macdonald, and was followed by anumber of well-sustained discussions on important subjects, Thesection of Chemistry also was notable for the address of its President,Professor James Walker, on the history of Physical Chemistry,which is now so intimately associated with the latter-day developments of physiology.The foundation of the Bio-chemical Club in London during theyear is an indication that biechemists are realising, not only theirstrength, but also the importance of union, which forms so large anelement in strength.Its meetings hitherto have been highlysuccessful, and are combinations of scientific discussion with themore social intercourse which accompanies and follows the eatingof dinners. The Club is looking forward with hopefulness to a not-distant future when it will develop into a Society with a journalof its own.Among the new books of the year it is necessary to mention atext-book of comparative physiology by Professor Putter.2 Thisis not of the same ambitious character as that edited by Winter-stein, t o which allusion was made in last year’s Report, but it isnevertheless a comprehensive treatise, and not too bulky.I n theinvestigation of the lower, as well as of the higher, animals, chem-istry is playing a conspicuous part, and in Professor Putter’s bookspecial prominence is assigned to the r61e of physical chemistry inthe elucidation of vital problems.Another book which may be read with interest and profit isentitled, “ Chemical Phenomena in Life,” and its author is ProfessorFrederick Czapek,3 of Prague.It only extends over 148 smallpages, but the amount of information packed within this smallcompass is really remarkable. There is no indication of undue2 (‘ Vergleichende Physiologie.” A. Piitter. FiJcher ; Jena, 1911.3 Harper’s ‘‘ Library of Living Thought,” 1911184 ANNUAL REPORTS ON THE PROQRESS OF CHEMISTRY.compreseion; the facts are stated in a clear, convincing, and com-prehensible style. Professor Czapek is a botanist, but he dealswith his subject from the point of view of general biology. Heshows how many of the phenomena of life are rendered intelligiblein the light of colloid chemistry, and by the conception of enzymesas organic catalysts. The same subject may, of course, be studiedin larger and more elaborate treatises, but to those who are notphysical chemists, a little book of this nature is a veritable godsend;it gives in outline the main facts, the new ideas, and explainsl insimple terms the new language which has been introduced intoscience by the physical chemists.Periodical literature, as I have already indicated in my openingsentence, remains quite as voluminous as in former years.To siftthe chaff from the wheat is not possible a t present. That only canbe performed by the reviewer of the future. Many pieces oforiginal work which appear valueless a t the time of publicationoften turn out to be of exceptional importance, and the converseis equally true. It is also impossible to attempt, even in outline,a survey of the whole output of the year or to classify it.Thepublished papers deal with practically every branch of the subject.The only remaining alternative is to follow my custom of previousyears, and make a selection, which I trust will be found a judiciousone.I propose, then, in the first place, to deal with one or twopoints of nomenclature ; next, rapidly t o review a certainnumber of papers which appear in my judgment to beof exceptional interest, and, finally, to select for rather moreextended notice a few of the topics which are attracting attentiona t the present day. In this preliminary stage of my essay it isimpossible to forecast with certainty what these topics will be, buta t this point my intention is to deal with three only: first, theenzymes concerned in nuclein metabolism, a somewhat specialisedand technical albeit important subject; secondly, the vexed ques-tions which have centred around “Standard Bread,” a subject ofinterest even to the man in the street; and the third subject willbe a pathological one, namely, the causation of that tropical diseasewhich is named “beri-beri.”Some Questions of iVomenclatu>re.The terminology of enzymes has settled down in the majority ofcases to the following rule.They are usually named after the sub-stances they split up, and end in the affix ase ; for instance, maltase isthe name for the enzyme which decompmes maltose into the smallePHYSIOLOGICAL CHEMISTRY. 185molecules of dextrose, lipase for a fat-splitting enzyme, and so forth.In many cases the reaction is a reversible one, and the same agentwhich produces the decomposition under certain conditions, willunder certain other conditions produce a synthesis of the simplerinto the more complex material.The main condition which influ-ences the result is, w is well known, the law of the influence ofmass action. Hans Euler and S. Kullberg have, however, pointedout that in certain cases, a t any rate, one enzyme is employed inthe cleavage, and another enzyme comes into play in the syntheticact. They could find no evidence that the enzyme which builds upphosphoric acid esters of carbohydrates, and which is found inyeast and other moulds, has any action a t all in splitting up theseesters into their component parts.Euler5 suggests that in suchcases the termination ese should be adopted instead of ase, andconsequently speaks of the enzyme in the example just quoted asp7hosphates_ee. Another instance where such a system of terminologywould be useful is what E. S. London entitles, ‘‘ A reversible phenemenon in the action of intestinal juice on the products of caseindigestion”; at a certain stage the milk protein undergoes jellying,and the subsequent liquefaction is apparently the result of theaction of a different enzyme.Life, so far as its chemical activitim are concerned, has recentlybeen defined as consisting of a series of reversible reactions. Thisis probably as correct a definition of vital metabolism it5 is possiblein the present state of knowledge, but like all terse attempts tocompress within a very small nutshell a very complex problem, itlacks completeness, and allows of no exceptions, which are doubtlessplentiful.Be that as it may, reversibility is observable in living structuresin cases which permit of no obvious chemical explanation. In therealm of psychology, bhe only region in wliich, according toCzapek in the book already mentioned, physicechemical laws arenot a t present applicable, a- change of mind and a recantation ofviews are not entirely unknown.Coming, however, to more matterof fact phenomena, Sherrington has furnished many instances wherereversal of normal nerve action may be brought about under theinfluence of certain drugs, for example, chloroform. These ar0 notlimited to blood-pressure effects which he had studied in his earlierwork, but may occur also in reflexes carried out by skeletal muscles.7Another example is furnished by the investigation carried out byZcilsch.physiol. Chem., 1911, 74, 15; A., i, 1051.Ibid., 13 ; A, i, 1051. Ibid., 301 ; A . , ii, 1000.7 C. S. Sherrington and Miss S. C. M. Sowton, J. Physiol., 1911,42, 383 ; d., ii,753 ; see also Owen and Sherrington, Strychnine Reversal,” ibid., 43, 232186 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Dale and Laidlaw 8; they found that cytisine, the alkaloid oflaburnum seeds, has an action similar to that of nicotine in lessen-ing or reversing the usual effect of stimulation of the chorda tympaninerve in producing an increased flow of saliva.Another a.phorism a good deal older than the one quoted a fewparagraphs back, is that language was given to man in order toconceal $is thoughts. One cannot help thinking of this whendealing with the second case I take under the heading nomencla-ture; I mean the introduction of the appalling word aprrhegma;thus among this year’s Abstracts I find the title, “P-Alanine as aBacterial Aporrhegma.”g The word was first introduced a yearor two ago, but would be better expunged from the literature.The meaning of the word is a substance split off by biologicalaction.Another new and useful word is acupniu, which has been intro-duced by Dr.Yandell Henderson, and is gaining acceptance.Carbon dioxide has in the past been looked upon chiefly as a wasteproduct, and of but little use to the organism.We now know thatcarbon dioxide fulfils inter alia the useful office of being the normalstimulus to the respiratory centre, and it assists in the dissociation ofoxy-haemoglobin in the capillaries. I f , owing to forced and exagger-ated respiratory efforts, this gas is swept out of the blood so thatits quantity is reduced below a certain “ threshold,” the respiratorycentre is no longer thrown into action, and cessation of breathing(apncea) is the result. I n normal circumstances, when thecarbon dioxide again accumulates, respiration sets in once more.There are, however, certain conditions in which it lessening of thecarbon dioxide content in the blood may produce a cessation ofbreathing, which is serious or even fatal.Notable among theseconditions is that produced by surgical and other forms of shock.”Henderson has worked out this aspect of the question in a seriesof researches, and has bestowed the term “ acapnia ” to the diminu-tion of the carbon dioxide, which is the cause of the symptoms.The latest of this series10 appeared about the middle of the year,and in this it is pointed out that acapnia is a frequent concomitantof the glycosuric state, and that in certain forms of experimentaldiabetes, prevention of acapnia obviates disturbances of the sugar-regulating functions. As long ago as 1889, Labousse pointed outthat injection of “ peptone ’’ causes acapnia, although he did notemploy that expression; it is now found that this also leads to8 J.Physiol., 1911, 43, 196 ; A., ii, 997.9 D. Ackermann, Zeitsch. Biol., 1911, 56, 87 ; A., ii, 757.10 ‘(Acapnia and Glycosuria,” Y. Henderson and F. P. Underhill, Amer. J.Physiol., 1911, 28, 275 ; A., ii, 813PHYSIOLOGICAL CHEMIBTRY. 187hyperglycaemia. It is often a long time before physiological dis-coveries filter through to the rank and file of medical practitioners,but one is rejoiced to hear that practical physicians are alreadyappreciating the va.lue of Henderson's work, and are thus beginningt o realise, not only the importance of carbon dioxide in the body,but also the meaning of symptoms which previously puzzled them.A mention of diabetes prompt,s one a t this point to allude byway of parenthesis to an important paper by F.P. Underhill andM. S. Fine11 on pancreatic diabetes. The hypothesis they advancecan only be fully understood by studying the paper in full, a taskthat will amply repay the reader. The underlying assumptionis that there exists between the liver, pancreas, and adrenal bodiesan inter-relation which keeps the amount of blood sugar constant.The action of the internal secretion of the pancreas is to facilitatecarbohydrate katabolism ; therefore, when the pancreas is removedor its function is in abeyance, sugar aocumulates, because theopposing effect of the adrenals has full sway. On the other hand,if adrenal function is in abeyance, the deleterious effects of depan-creatisation are lessened ; they find that hydrazine prevents theglycosuria which occurs after extirpation of the pancreas, in allprobability because this drug diminishes adrenal activity.Pnein and antipmein are illustrations of names of unknownsubstances whiEh are derived from their physiological action.Pnein or pneumin is a thermostable material found, according toBat'telli and Stern,12 in most tissues which accelerate t.heir primaryrespiration processes.Antipnein or antipneumin is destroyed bya temperature of 6 5 O ; it is specially abundant in the spleen, andalmost absent in muscle. Its na.me indicates that it inhibits orhinders oxidative processes. Whether such terms " catch on " andlive depends on many circumstances. Many words become familiar-ised by long usage before their chemical composition is worked out,and so the old names stand. There is little doubt, for instance, thatadrenaline and secretin are destined for a long life.Peptone andprotagon are still used, although they can no longer be regardedas connoting chemical individuals. The prolonged existence ofPopielski's vmo-dilatin appears more questionable, and the con-tinued use of the word " ptomaine '' also appears undesirable. Thehistory of our knowledge of the bases obtainable from proteins is avery interesting 0118.13 Many of them can be obtained by simplyremoving carbon dioxide from amino-acids, and one of the latestof these obtained in this way from histidine is 4-p-aminoethylgly-l1 J. Biol. Chern., 1911, 10, 271 ; A . , ii, 1001.l2 Biochem. Zeitsch., 1911, 33, 315 ; 36, 114 ; A., ii, 748, 1008.l 3 See article by G.Barger, Science Progress, 1911, p. 221188 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.oxaline or ~-iminazolylethylamine.~4 This is a constituent of ergot,of the intestinal mucous membrane, and is probably identical withPopielski’s vaso-dilatin. Its effects are also similar to thoee whichare produced by a toxic substance formed in an anaphylactic animalby the injection of an innocuous protein.However desirable it may be for sentimental or historical reasonsto retain words which have become familiar, there can be no doubtwhatever that words framed on chemical misconceptions ought to beruthlessly expunged. Such a word, for instance, is “ quadriurate.”Rosenheim 15 was the first to prove that these substances, originallydescribed by the late Sir William Roberts, are mixtures of biuratesand uric acid.This view has been repeated and confirmed byR. Kohler16 during the present year, who was unacquainted withRosenheim’s work. W. E. Ringer17 has also investigated the samequestion, and although he lends no support to the chemical entityof these substances, suggests that the peculiar behaviour of uraticdeposits in urine, which originally led Sir W. Roberts to his viewthat uric acid and a biurate were united chemically, can be bestexplained on the view that this is a case of “ solid solution.”Another case of nomenclature, and the last on my list, is thatof caseinogen and casein. It was in the year 1890 18 that I proposedthese names for the principal proteins in milk and cheese respec-tively, as previous to that time the single word casein was usuallyapplied to both indiscriminately, and this led to confusion.Thewords certainly possess the merit of conveying to the mind easilythe relationship of the two substances to one another, and this isby no means unimportant, especially to those who have to deal withstudents. The terms were obviously suggested by the somewhatsimilar genetic relationship between fibrinogen and fibrin, and theanalogy still holds, although it may not be complete in every detail.They have been very generally adopted by those who write in theEnglish tongue, but those who write in German continue t o employthe word ‘‘ casein ” for the milk protein, and the word ‘‘ paracasein ”for the curdled prsduct.19 I n view of this international difficulty,14 Barger and Dale, J.Physiol., 1911, 41, 499 ; Dale and Laidlaw, ibid., 43, 182 ;d., i;, 217, 1017. See also, in this connexion, W. H. Harvey, J. Path. Bact.,1911, 16, 95 ; A., ii, 1013, on the part played by such bases in the production ofkidney disease ; and in the causation of high blood pressure, see Bain, Zancet, 1911,i, 1409 ; A., ii, 631.l5 Rosenheim and Tunnicliffe, Auncet, June 16th, 1900.16 Zeitsch. physiol. Chem., 1911, 70, 360 ; A., i, 243.l 7 B i d . , 75, 13, A., i, 1044.19 Recent intercsting {work on milk curdling, especially on the changes in theprotein antecedent to actual curdling, and amplifying Hammarsten’s classical workSee also Rosenheim, ibid.,71, 272 ; A., i, 403.l8 J.Physiol., 1900, 11, 448PHYSIOLOGICAL CHEMISTRY. 189I recently put the question to our newly-founded Bio-chemicalClub whether it would be wise to surrender the use of the wordscaseinogen and casein in favour of the German system, and I wasglad to find almost complete unanimity in favour of my own terms.They will therefore continue to live on, and if the Germans do notfall into line, no one need suffer, except perhaps the Germanstudents, who will continue to wonder why the protein of milkshould be called cheese, and why the protein of cheese is calledsomething else.Miscellaneous Papers of Interest .I now come t o the second item on my programme, namely, briefnotices of various papers whiich appear to me important ones.Finding it difficuh to arrange them in any logical order, I proposeto take them almost haphazard, and will first allude to some on thesubject to which I was referring in my last paragraph.Milk.-The vexed question whether pepsin and rennet aredifferent enzymes or not still continues to excite interest.The prosand cons are about equally balanced if one, counts numbers; butwhen one looks to the authoritative quality of the writers, thebalance of evidence this year, a t any rate, appears to be in favourof the old view that the two enzymes are distinct. The most con-vincing of these papers is that which has been written by theveteran ‘Olof Hammars*n,20 who from the first has dkputedPawloff’s view that the two enzymes are identical. One is glad tosee that Rammarsten, who has resigned his professorship, is stillactive in research.He has continued, for example, his work onthe bile of the rarer animals, and this year has investigated that ofthe hippopotamus,21 and found that further varieties of bile acidsexist in the animal kingdom than those which were previouslyknown. He has also since his retirement produced a new editionof his well known text-book,22 and that has been followed by anEnglish translation by Professor Mande1.23To some extent the milky mantle has fallen apon ProfessorHammarsten’s successor a t Upsala, Professor Hedin, who contri-butes a paper on the “Specific Inhibition of Rennet and Differencesbetween Rennets.”a He finds that by warming neutral infusionson the subject will be found in a paper by Bang (Sknnd.Arehiv. Physiol., 1911,25, 105 ; A . , i, 826).2o Zeitsch. physiol. Chem., 1911, 74, 142 ; A., ii, 998.21 Ibid., 123 ; A., ii, 1010.z2 “ Lehrbuch d. physiol. Chem.,” 7th edition, Wiesbaden, 1910.23 (‘ Textbook of Physiol. Chem.,” translation of the above, Wiley, New York,1911.2J Zeitsch. physiol. Chem., 1911, 74, 242 ; A., ii, 998190 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of the gastric mucous membrane of the guinea pig, calf, and pikewith dilute ammonia and then neutralising, substances are formedwhich inhibit rennetic action, but the inhibitory substances onlyinhibit the rennet of the animals used. The conclusion is drawnthat this specific action indicates that the enzymes they inhibit, arespecific also.This conclusion would have been strengthened if ithad also been shown that the rennet, say, of the calf did not producecurdling of the milk of other animals. There is no word aboutthis; in fact, all the evidence points the other way; so far as isknown, the rennet from any animal will curdle any species of milk.Heat Coagulation of Proteins.-This question has been taken upby Dr. C. J. Martin and Miss Chi~k.~5 They show in the new lightshed by physical chemistry on colloids, and in the new language ofthat science, that many of the old facts become intelligible. Heatcoagulation is not a mere temperature effect, but is really a reactionbekween protein and water, and is influenced by temperature inaccordance with the law of Arrhenius, the temperaiure-coefficient,however, being a very high one.This “ denaturation ” of the proteinis followed by the separation of the altered protein in particulateform (agglutination). The first step, denaturation, is, if meansare taken t o prevent changes in acidity, a reaction of the firstorder; as the protein is precipitated, free acid is progressivelyremoved from the solution, and this second change, “ agglutination,”occurs more rapidly than the, denaturation. A number of otherissues are disfcussed, such as the influence of salts on the pheno-menon, but these the reader must discover for himself. My objectis fulfilled by calling attention to this interesting research.The Use of Elastin for Isolating Pepsin.-The annual output byAbderhalden and his colleagues continues unabated.Most of itis useful spade work, working out details on the lines of previousresearches: the digger may chance to unearth a precious stone nowand then. Abderhalden’s 26 precious stone this year is the discoveryof the usefulness of elastin for the isolation and detection of pepsin.It has long been known that if fibrin is placed in a solution con-taining pepsin, the enzyme is adsorbed and removed, and can besubsequently washed out from the fibrin. Elastin and other solidproteins act in a similar way, but the special advantage of elastinis its comparative insolubiiity in digestive juices, so that subse-quently the enzyme can be obtained almost free from proteolyticproducts.Other enzymes are adsorbed in a similar way, but so farAbderhalden has confined his work almost exclusively to pepsin.25 J. Physiol., 1910, 40, 404; A., 1910, i, 597; ibid., 1911, 43, 1 ; A., i, 822.26 Zeitsch. physiol. Chem., 1911, 71, 315, 339, 449 ; 74, 67, 411 ; A . , i, 511 ; ii,506, 999PHYSIOLOGICAL CHEMl STRY. 191By this method i t has been shown that proteolytic enzymes areabsent from the fzeces, but by far the most important resultobtained is the presence of pepsin in an active form in the intestine,into which it is carried and protected by the elastin or other com-paratively insoluble proteins of the food. Hitherto, it has generallybeen supposed that the action of pepsin ceases beyond the confinesof the stomach.There is still a large amount of ignorance inrelation to the individual pax& played by pepsin, trypsin, anderepsin in protein cleavage, but it can hardly be doubted that inclearing away this ignorance investigators will have in the futureto consider a new factor, namely, the co-operation of the gastricenzyme pepsin with the others in the much more complete digestiveprocess which takes place in the small intestine.Origin of the Hydrochloric Acid of the Gastric Juice.-Passingnext to the inorganic ally of pepsin, we come across an interestingpa.per by Miss Fitzgerald.27 Many workers have employed variousmicrochemical tests in order to localise the seat of formation ofthe acid of the gastric juice, and although the evidence availableclearly points to the association of acid formation with the parietalor oxyntic cells of the gastric tubules, no absolute certainty hasbeen attained; neither has i t been proved beyond cavil that hydro-chloric acid exists in demonstrable form in the secretion before itreaches the free surface of the mucous membrane.This has nowbeen finally set at rest. Solutions containing potassium ferrocyanideand ammonium ferric citrate were injected into rabbits and guineapigs, and the animals were killed from three to thirty hours later.This mixture readily formed Prussian blue with hydrochloric acidof a much less concentration than that contained in gastric juice,but gave no reaction with sodium phosphate or carbon dioxide.Microscopic sections of the stomach showed the presence of Prussian-blue in the lumina of the gland tubules and in the canalicdi of theparietal cells.The acid is thus shown to be already in a free statein the secretion of the cells which form it. A faint blue colorationthroughout the protoplasm of the same cells seemed to indicateits presence there too. The chemical operations involved in theliberation of the free acid from chlorides is another questionaltogether; but excess of chlorides in the parietal cells as comparedwith the asmount in the pepsin-forming cells was shown to bepresent.The Physiological Protein Minimum.--I do not mean here toreopen the old question which the name Chittenden suggests, butto look a t the subject from another point of view. During stam&tion the loss of nitrogen per day soon reaches a constant level,27 Proc.Roy. Xoc., 1910, B, 83, 5 6 ; A., ii, 50192 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.and in this condition it might be thought that if protein wereadministered in such amount that its nitrogen equalled the lw, thedrainage of nitrogen from the body would be arrested. Theclassical experiments of Voit showed, however, that nitrogen equili-brium is not reached until the amount given is two or three timesgreater than the amount lost during inanition. In 1909 LouisMichaud 28 attacked this problem afresh, using dogs, as Voit did inhis experiments, with the conclusion that the result varies accordingto the sort of protein used in feeding. A mere nitrogen estimationin the food protein is not enough; the value of a protein dependsrather on the proportion between its cleavage products.If aprotein foreign to the body, such as edestin, is used, equilibriumwas not reached until excess was given as stated by Voit. But ifthe food protein employed was the flesh or other tissues of anotherdog, then equilibrium is reached more easily; in fact, it can beattained by giving just enough to replace the inmition daily waste.Horse flesh or casein were intermediate between edestin and dog’sflesh in this relationship.This paper attracted much attention, and, put in a sentence, themain conclusion is that a live dog can make its tissues most easilyfrom dead dog. I f this were pushed to a logical conclusion, wemight even formulate a scientific defence of cannibalism.Howeverlikely such a conlclusion might appear to the superficial thinker,it would really upset much of the recent knowledge acquired bypainstaking work on protein metabolism. We know with almostabsolute certainty that a small fraction only of the protein ingestedis actually used as a “flesh-forming food”; the larger fraction isalmost immediately cast out as waste in the form of urea. It is,however, quite conceivable that thisl waste might be lessened byusing protein food as near as possible in composition to the proteintissues peculiar to the species of animal under observation.A good many people have taken up the point. Frank and Schitten-helm29 confirm the general idea; they find that the minimumamount of protein capable of maintaining nitrogenous equilibriumafter inanition is appreciably less when the protein administeredis the protein of dog’s muscle than it is when any other kind ofprotein is employed for feeding purposes.Other workers,3O however,find that the advantage of feeding dog on dog, although present, isnot a very great one. This is what one would rather have antici-pated. Even Frank and Schittenhelm31 found in their further28 Zeitsch. physiol. Chem., 1909, 59, 405 ; A., 1909, ii, 498.2g Ibid., 1910, 70, 98 ; A . , ii, 127.30 See, for instance, von Hoesslin and Lesser, ibid., 1911, 73, 345 ; A., ii, 904.31 Ibid., 157 ; A., ii, 904.Also London and Rabinowitsch, ibid., 1911, 74, 312 ; A . , ii, 999PHYSIOLOGICAL CHEMISTRY.193work that in ordinary nutrition (apart from inanition) nitrogenousmetabolism runs practically the same course, whatever form ofprotein was given in the food.Synthesis of Amino-acds in the Uocly.-A series of papersinitiated by Franz Knoop on this subject bids fair to yield impor-tant results. He showed 32 that a-amino-acids after parting withtheir amino- and carboxxl groups are broken down in a mannersimilar to the next lower fatty acid, and that they may be acetylatedin the bodies of animals. Further, a-ketonic acids may take upnitrogen in the body with the production of optically active a-amino-acids ; a-hydroxy-acids may also be converted into a-amino-acids.Embden and Schmitz,33 by means of perfusion experiments on theliver, discovered that p-hydroxyphenylpyruvic acid was convertedinto tyrosine by that organ, and that after perfusion with p-phenyl-pyruvic acid, phenylalanine could be isolated in the form of a carb-amic acid; leucic acid gave rise to leucine-carbamic acid.I f the liverwas rich in glycogen, during simple perfusion part of the glycogenga-ve rise to alanine, lactic acid and pyruvic acid being apparentlyintermediate products. Knoop and Kertess 34 fed a dog on a-amin+y-phenylbutyric acid, and its urine contained the I-modification ofthis acid, its acetyl derivative, and d-a-hydroxy-y-phenylbutyric acid.In addition, butyric acid was formed, indicating degradation ofthe amineacid through the ketonic acid to the next lower fattyacid. When fed with the a-ketonic acid, the products wered-a-hydroxy-7-phenyibutyric, acetylaminophenylbutyric, and hip-puric acids.The formation of the same hydroxy-acid in bothinstances, and in larger quantity from the ketonic acid, is confirma-tory of the view that the amino- is converted into the ketonic acidin the animal body. The acetylamino-acid is also in each instancederived from a probably inactive intermediate compound, and notby direct acetylation, as Neubauer and Warburg 36 considered t ooccur in perfusion experiments on the dog’s liver.The Corpus Luteurn.-The year’s work contains a good deal aboutinternal secretions in general, and adrenaline in particular, but Ipass from these to consider one point only. It is well known thatafter the exit of the ovum from the ovary, its follicle is filled upby the growth of yellow-coloured cells, and that the corpus luteumso formed attains a great size if pregnancy ensues.It has beengenerally assumed that these cells form a hormone,” and thefunction generally attributed to this chemical messenger is to sssist32 Zuitsch. yhysiol. Chem., 1910, 67, 489 ; A . , 1910, ii, 880.yJ Bioc;h(vn. Zeitsch., 1910, 29, 423; A . , ii, 53.‘I4 %Cit.wh. physiol. Chem., 1911, 71, 252 ; A, ii, 514.35 Ibid., 1910, 70, 1 ; A . , ii, 53.KIt‘P. -VOL. VIII. 194 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in some way in the successful fixation of the ovum in the uterus.Another series of observations on the causation of growth in themammary glands, culminating in milk production, failed to revealthe presence of any secretory nerves in the milk glands, correspond-ing with what are known to exist in the salivary and sweat glands;and evidence that mammary growth occurs in cases where therecan be no possible nervous connexion between the generativeorgans and the mammary glands pointed to the conclusion thatthe correlation must here be chemical rather than nervous.A fewyears ago Professor E. H. Starling, working with Miss Lane-Claypon, thought that the hormone in question must be secretedby the foetus, because injection of faetal extracts led to a somewhatimperfect hypertrophy of mammary tissue. Doubt was, however,felt in many quarters whether this could be the whole explanation,for mammary evolution occurs in many virgin animals, in whichovulation is not followed by pregnancy.C. H. O’Donoghue36 hasinvestigated the question recently in the Marsupial cat known asDasyurus, which from many points of view, into which it is unneces-sary to enter here, is a particularly suitable animal for the solutionof the problem. He finds a close correspondence between the stagesin the development of the corpus luteum and the mammaxyglands, and finally concludes that it is the hormone secreted bythe former which is the inciting cause of the growth of the latter.On the other hand, F. $1. A. Marshall,37 who has investigated asimilar question in the dog, arrives at the conclusion that theinternal secretion from the ovary, which brings about I‘ heat,”originates in the interstitial cells of that organ.It is quite possiblethat the ovary may form more than one internal secretion, andonly one of these acts on the mammary glands.The Effect of Choline o n Blood Pressure.-Mott and I appear tohave been the first to recognise the physiological and pathologicalimportance of choline. It is a base derived from the cleavage ofcertain phosphatides, notably lecithin. Its presence in such fluidsas that which bathes the spinal cord and brain would be a tangibleproof of the disintegration of nervous matter such as occurs inmany of the grosser diseases of these organs, for phosphatides hereare much more abundant than in other tissues. Many physiologistshave taken up the choline question, and some have entirely deniedthe existence of choline in the cerebrespinal fluid, even after36 Proc.yhysiol. Soc., 1911, xvi. ; J. Physiol., 43 ; Quart. J. Micro. Scknce,1911, 57, 187. Another paper on the corpus luteurn calls attention to certain toxicefl’ects produced by a lipoid substance that can be extracted from i t (Bonin andAiicel, Compt. rend., 1910, 151, 1391 ; A . , ii, 129).j7 Proc. pl~ysiol. SOC., 1911, xxi ; J. Physiol., 43PHYSIOLOGICAL CHEMISTRY. 195massive disintegration. It may be freely admitted that the testahitherto devised for identifying the base are only relatively con-clusive, for sufficient material has never been collected for acomplete anaiysis. All, however, seem now to admit that thematerial which is undoubtedly present and so distinguishes thepathological from the normal fluid, is, if not choline itself, asubstance nearly related to it, perhaps a derivative of choline, andthe latest theory advanced is that it is trimethylamine, a cleavageproduct of choline.38 This is a question quite apart from that ofcholesterol, which all admit is present in cerebrclspinal fluid incases of chemical breakdown of nervous tissues.Another point in relation to choline is whether, when injectedinto the blood stream, it produces a rise or a fall of blood-pressure.This ought not t o be a difficult question to answer.The operativeprocedure is simple, and the preparation of pure choline or of itshydrochloride presents no great difficulties. The majority ofobservers are agreed that the effect is a fall of arterial pressure inaccordance with the original statements of Mott and myself.30 Butthe question has curiously enough raised a keen and bitter contreversy, because certain observers in Russia, Modrakowski andPopielski,40 have persistently maintained that everybody exceptthemselves is wrong, and that the typical effect of an injection ofcholine is to raise arterial pressure, and that the opposite resultobtained by others is due to their having used impure materials.One always distrusts observers who claim for themselves a monopolyin the capacity t o carry out correctly a simple piece of chemicalanalysis or physiological experimentation, and one cannot thereforebe sorry for the wholesome castigation administered to Popielskiand his colleagues by Abderhalden and F. Miiller.41 This is notby any means the first of their papers dealing with the subject, butit is the most thorough, and will in the minds of all reasonablepeople settle the question once and for all.Some of their prepara-tion was sent t o Popielski ih order that he might test the matterfor himself, and he reported that it produced a rise of blood-pres-sure. Unfortunately for Popielski, the specimen sent (by mistake)was an impure one, which according t o him should have produceda fall of blood-pressure. It did produce a fall of pressure inBerlin, and so did the pure specimen. Many strange things have38 C. Dorke and F. Golla, Bio-Chem. J., 1911, 5, 306 ; A . , ii, 212.39 These observers have recently been joined by the following : Z.Berlin (Zentr.Physiol., 1910, 24, 587 ; A., ii, 516) and A. Lohmann (Zeitsch. B i d , 191 1 , 56. 1 ;A., ii, 630).4o Popielski's riiost recent paper will be fouiid i n Zeitsch. physiol. Chern., 1910,70, 250 ; A., ii, 124.Ibid., 1911, 74, 253 ; A., ii, 994.0 196 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.occurred on the Russian frontier, but this transformation surelybeats the record.Manganese and Vanadium as Constituents of Animai? Tissues.-Everyone acquainted with the history of chemistry will rememberthat the element phosphorus was first discovered in an animalproduct, namely, urine. It was not until nearly half a, centurylater that it was found in the mineral kingdom. This discovery inthe eighteenth century evoked as much interest in the scientificworld as the discovery of radium has done in our own day.As arule, however, the discovery of new elements occurs in the inorganicworld, and later on search is made for them in animal tissues, andthe list of the elements present in the latter thus grows in length.The discovery of iodine, however, in 1811 dates from the investiga-tion of se*weeds, and it was not until about twenty years ago thatBaumann showed that it is also present in organic combination inthe secretion of the thyroid gland in animals. The long list ofelements found in animal tissues must now have added to it twomore, namely, manganese and vanadium. The presence of man-ganese in such tissues which had been occasionally noted in thepast was attributed to accident; and manganese, like copper andlead, was therefore supposed to be due to contamination with thematerial used in utensils employed for cooking, etc., or to the useof drugs. No doubt in the majority of instances this is the correctexplanation.Copper, however, we now know is contained in a tleast two physiological proximate principles, namely, haemocyanin,the blue pigment in the blood of many crustaceans and molluscs, andturacin, the red pigment in the feathers of the plantain-eating birds.It now seems equally necessary to include manganese as a normalbody constituent in certain forms of animal life. According t oPiccinini,42 it occurs in varying quantities in the different tissuesof the animal and human organism. It is obtained from the food,but does not disappear when a diet free from it is taken.Theaddition of manganese to the diet is also stated to increase the ironof the blood, liver, and spleen. One would hesitate from thisdeecrrption to include manganese among the normal constituentsof the body; its presence partakes more of the accidental order.and like many poisons, although manganese itself produces noobvious toxic symptoms in these doses, it appears to remain in thetissues, and is excreted with difficulty. But in the case of certainaquatic animals there is a different story to relate. Its presencein the fresh-water mussels or clams, Unio and Anodon, was firstnoted by Bradley in 1907,13 aud in their eggs. His promise to4L Arch. farm. sperim., 1910, 9 ; A., ii, 622.43 J .Biol. Chem., 1907, 3, 151 ; A . , 1907 ii, 567PHYSIOLOGICAL CHEMLSTRY. 197investigate the source of the metal and its physiological meaningwas only fulfilled last year.44 He found that the element can bedetected in most of the organs of the mussel, but is most abundantin gills and mantle. The source of the element is the food theseanimals ingest; and that, of course, is the source of any othersubstance found in the body. They feed on crenothrix and diatoms,which are able to concentrate manganese from its very dilutesolution in the water. I n lakes where the water is very pureneither crenothrix nor mussels are found, nor do they live ifplaced there ; the manganese has probably a respiratory functionin the tissues and blood of these larnellibranchs, much as iron hasin our own blood.No one had previously dreamt that the comparatively rare metalvanadium was a pmsible constituent of animal structures, butHenze 45 has found it in the blood-corpuscles of certain ascidians,Phallusia being the animal he made most of his observations on.These corpuscles are extremely acid t o litmus, and the acid is inlarge part volatile with steam, and probably organic. On exposureto air, the corpuscles turn yellowish-green t o blue; the chromogenof this pigment is soluble in water and in acetone; in time it turnsbrown. On incineration it yields about 15 per cent.of vanadicacid (V,O,). This is just one of those discoveries which impressesthe imagination; even in the well-tilled field of bio-chemistry thereare doubtless plenty of discoveries still awaiting discoverers.PhysioEogicaZ Climatology.-This paper by Professor Osborne, ofMelbourne,40 is the first of what promises to be an instructive andinteresting series.It illustrates the usefulness of long holidays andopportunities for travel. One compensation we have in the migra-tion of some of our younger physiologists to the colonies is that innew atmospheres they see things in fresh lights. The particularsubject treated of in the paper under consideration is the relationof the loss of water from the skin and lungs to the external tem-perature in actual climatic conditions. The usual text-book state-ment that heat lost by radiation and conduction from the skinmakes up the greater portion of the heat lost from the body, isonly true under certain conditions ; an air-temperature equal tothat of the body would reduce this loss to zero.I f the metabolismof the body is constant during rest, and the heat production there-fore is fairly constant too, it follows that if the air-temperature israised, and loss by radiation and conduction consequently lessened,the heat loss due to evaporation must make up the balance; other-44 J. BioL. Chcm., 1910, 7, xxxvi, and 8, 237 ; A., 1910, ii, 731, 979.45 Zcitsch. physiol. Chcm., 1911, 72, 494 ; A., ii, 740.J. Physiol., 1910, 41, 345 ; A., ii, 124‘198 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.wise heat accumulation will occur, and the body temperature willrise.It would be expected, therefore, that the water loss wouldbe a linear function of the air temperature. This simple relation-ship, however, does not occur, and the cause of the perturbationsin the straight line is not clothing, but is more complex; onefactor, at any rate, is t4he humidity of the air, and another is thevelocity of its movement. If the air is dry and in movement, itwill tend to dry the skin, and if body temperature and skin inbibi-tion are to be kept constant, then the metabolism must beaugmented. What apparently does occur is a compromise : theskin loses some of its water of imbibition, and the metabolismundergoes a moderate rise. This explains the unpopularity of theeast wind in N.W. Europe.Another factor is the amount of ventilation via the lungs; thisis increased when the atmospheric temperature is high, and isknown familiarly in the lower animals, as when a dog pants in thesummer time.How the respiratory centre is affected by a highair-temperature is a puzzle, for the body temperature does notrise; possibly the carotid blood may become heated in its passageup the neck.Osborne also found that the carbon dioxide excreted variesdirectly, not inversely, ag the external temperature. The increasein pulmonary ventilation will in part explain this; more carbondioxide is produced from the additional work of the respiratorymuscles, and more is “washed out” from the tissues. There is,further, some indication that the respiratory quotient rises withrising shade temperature.Harvey Sutton found this quotientapproached unity when the wet-bulb thermometer rose in a roomhe could artificially make warm and moist, and made some sugges-tions regarding the relation of this reaction to the preponderanceof carbohydrates in the diets of tropical aboriginnls.This imperfect and hasty outline of the paper will at leastindicate its practical importance, and make us await with interestfurther contributions on the subject from its author.Creatine and 0reatinine.-I had intended at this point to inserta brief review of the somewhat voluminous work on this subjectwhich has appeared throughout the year. Looking through thepapers once more, however, I find little or nothing that throwsnew light on the very puzzling metabolic problem that thesesubstances present.New facts have been elicited, for instance, theindispensability of carbohydrate food for maintaining the normalcourse of creatine-creatinine metabolism, a function which is notexercised, either by fats or by proteins.47 Such facts, however, and.i7 TJ. B. Mendel and W. C. Rose, J. Biol. Chem., 1911, 10, 213 ; A . , ii, 1002PHYSIOLOGICAL CHEMISTRY. 199others (often conflicting) too numerous to mention are difficult tobring into line with each other, or with any general view of the realhistory of these substances in the body. For this reason, as well asexigencies of space, I prefer to leave the subject to some futuretime when the difficulties that surround the subject are more fullycleared up.Th.e Lipoz'ds.-For much the same reasons, I think it would bebetter to omit more than a passing reference t o the lipoids.Theycontinue to exerciw a great attraction for the researcher, althoughthere is some indication that the actual number of papers aboutthem shows a diminution this year. The work done has beenuseful and painstaking, but in the main is directed to the workingout of details; so here again the subject hardly lends itself togeneral discussion. As examples of the nature of the work inprogress, we may take that of Professor Lorrain Smith48 on thestaining reactions globules of fat and lipoid undergo in microscopictechnique; on methods of estimating such substances by the sameauthor; 49 a separation of the lipoids of egg-yolk,50 and so forth.It is not many years back that I devoted a considerable space ofone of my reports to the lipoids, and the subject is obviously onethat can wait further and fuller development in the future.This leaves me free now to take up the last section of my report,as outlined in its opening, and take up seriatim the three subjectschosen there for more extended treatment.Nucleic Acid and NucZeasP-s.In this instance I make no apology for returning to a subjectI have treated at length in former reports.For here a considerableadvance has recently been made, and our knowledge, both of thechemical composition of nucleic acid and of its fate in the body,is increasing by leaps and bounds.A t the risk of wearying some readers who have studied myprevious reports, I will briefly recapitulate what was known atthis time last year, in order to give some degree of completenessto my story.Nuclein is the name originally given by Miescher in 1871 to themain constituent of the nuclei of cells.He recognised that it wasa nitrogenous phosphorised organic substance in union with aprotein. The non-protein constituent of the complex has since beenknown as nucleic acid. Making rather a long jump to a laterepoch, Kossel isolated and identified many of the cleavage produchJ. Path. Bnct., 1910, 15, 53 ; A . , ii, 57.j!' Iijfd., 1911, 16, 131 ; A., ii, 1006.5o Serono and Palozzi, Arch. farm. sperisn., 1911, 11, 553 ; A., ii, 1005200 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of nucleic acid, and he separated out phosphoric acid and certaincrystalline bases, and noted in addition the presence of a carbo-hydrate.The bases Kmel mainly worked at are those which werenamed purine bases by Emil Fischer, and the four principal onesare hyp oxant hine (mono-oxypurine), xanthine (dioxypurine),adenine (aminopurinei), and guanine (amino-oxypurine). A t first itwas supposed that there were four nucleic acids, each of whichyielded a different base.Later other bases were separated out, which are derivatives ofanother cyclic nucleus, namely, pyrimidine.The work of Walter Jones, Levene, Steudel, and others showedthat ordinary nucleic acid yields two bases of the purine group,namely, adenine and guanine, and two of the pyrimidine group,namely, thymine (diketomethylpyrimidine) and cytosine (aminepyrimidone). Other bases when present are due to secondaryreactions.The identity of the carbohydrate was a matter ofdispute, some regarding it as a pentw, others as a hexose. Kosselregarded i t as a hexose mainly because he obtained from nucleina yield of lzvulic acid.Steudel appears to have been the first to present a provisionalbut complete view of the structure of the constitution of thenucleic acid molecule. He thought it consisted of a chain of fouratoms of phosphorus, each of which was united on the one sideto hydroxyl, and on the other to a hexose molecule. Each of thefour hexose groups in its turn was united to a base, a different basefor each hexose group.Almost simultaneously with this work, that of Bang showedthe existence in certain organs of a simpler form of nucleic acid,which yielded on decomposition only three substances, namely,phosphoric acid, a sugar of the pentose group, and one purine base,guanine.This was consequently termed guanylic acid.This brings us to the work of the years 1910 and 1911, and themore chemical aspect of the subject is discussed in a series ofpapers published in the Uerichte by Levene and his colleague^.^^One important point they made out was the identity of the carbo-hydrate; it is ribose, one of the pentoses. Levene and Jacobs 52very successfully defend this view against certain criticisms ofNeuberg on this question. Without going fully into the compli-cated problem of how the linking together occurs, one may givethe main view taken by these workers, and the new nomenclaturethey have introduced.A nucleic acid is designated a m c l e o t i d e ; thus Bang's guanylic51 Bey., 1910, 43, 3150, 3164 ; 1911, 44, 746, 1027 ; A., ii, 96, 408, 510.5'2 Ib'hzd., 1910, 43, 3147PHYSIOLOGICAL CHEMISTRY.201acid, which yields on hydrolysis only one molecule of ribose andone base (guanine), is a, moncmucleotide. As the number becomes2, 3, or more, we get di-, tri-, etc., nucleotides; thus the part ofthe molecule which yields the two purine bases, adenine (CJ35N5)and guanine (C,H,ON,), may be represented by the followingformula :OH H H H/ I II0: P . o . c H , ~ c ~ c - ~ - c H ~ c ~ H ~ ~ ~ 1 OHOH 1 I ~ -- 0 0H H H0: 1.O.CJ3, c I I .C-d--CH*C,H,ON,I \, 1 o H h 3 IOH 0By splitting off the phosphoric acid, what is left are the twocombinations of ribose and base; that is, ribose+adenine andribose + guanine. Such compounds are termed nucleosides ; it isunfortunate that nucleotide and nucleoside are names that are somuch alike, for i t will be difficult to remember which is which.These two nucleosides are named guanosine and adenosine respec-tively. By hydrolysis with acids the bond between the sugar andthe base is dissolved, guanosine yielding guanine and a-ribose, andadenosine adenine and &ribose. These two nucleosides may also bespoken of as aminonucleosides, because the base in each casecontains the amino-group. By the action of nitrous acid the twoaminwmcleosides are converted into the corresponding hydroxy-nucleosides by removal of the amino-group ; thus guanmine yieldsxanthosine (xanthine + ribose) and adenosine yields hypoxanthosine(hypoxanthine + ribose), also spoken of as inosine, another confusingitem in the new nomenclature.It will be noted I have not compli-cated the account of this work by introducing the pyrimidinecompounds of ribose, such as cytidine, that is, cytosine + ribose,about which less is known, but in which the linking is apparentlynot glycoeidic.Passing now to the physiological or metabolic side of the question,we have t o inquire whether within the body disintegrations occurwhich are similar t o those which we have just seen can be producedby chemical reagents.The answer is ((Yes,” and the agents atwork in the body are enzymes, to which one may give the generalname nuclcases.Before describing the details of this aspect of the subject,let us return for a moment to history; but it is only necessary formy purpose to go back to 1909, in which in my report I state202 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the following to be an outline of what was then known.53 I repro-duce the paragraph almost verbatim.(' The decomposition is accomplished by certain tissue enzymeswhich have been studied in extracts of tissues and organs. Theirdistribution varies a good deal, both in different animals and intheir different organs, but, speaking generally, they are mostabundant in the liver, spleen and kidney.54 The first to act iscalled rwclease; it liberates the purine bases from nucleic acid.The next to come into play are called deamidising enzymes, becausethey remove the amino-group; one of them, adenase, convertsadenine into hypoxanthine (mono-oxypurine) ; the other, calledg m n u s e , converts guanine into xanthine (dioxypurine) ; finally,oxydases step in, which transform hypoxanthine into xanthine, andxanthine into uric acid (trioxypurine).But even this does notbring the long list to a conclusion, for in certain organs (forexample, the liver) in many animals there is a capacity to destroythe uric acid after it is formed, and the enzyme responsible foruric acid destruction, and which normally protects the animal froma too great accumulation of this substance, is called the w'colyticenzyme ."Now this was complicated enough in all conscience, but furtherinvestigation in the light of the new knowledge we now possess ofthe chemistry of nucleic acid has shown that in reality it is morecomplex still.Starting at the beginning, that is, when nucleic acid enters thebody with the food, our first question is how far its disintegrationproceeds in the alimentary canal.Previous work on this questionhas mainly consisted of investigations in vitro. We are able now torecord experiments carried out by the more satisfactory method ofexperiments on the living animal. This was done by E. S. Londonand Schittenhelm,55 who employed dogs with appropriate fistulaefor the purpose. They found that nucleic acid is neither altered norabsorbed in the stomach, but that it is to some extent split upin the intestine; a small amount of purine bases is liberated, butthe major amount of the nucleic acid given is only broken down asfar as the mono-nucleotide or nucleoside stage, and these areabsorbed lower down the intestinal tube. In a later research,66they succeeded in isolating guanosine, and identifying it withcertainty; they, however, agree with Levene and Jacobs, to whose5s Ann.Report, 1910, 170.54 Fresh facts under this heading are contained in a paper by Jnschtschenko,Biochenz. Zeitsch.., 1911, 31, 377 ; A . , ii, 412.Zeilsch. physiol. Chem., 1910, 70, 10 ; A., ii, 52.56 lbid., 1911, 72, 459; A . , ii, 745PHYSIOLOGICAL CHEMISTRY.203work we shall pass immediately, that the final splitting occurs inthe organs and tissues.Levene and Medigreceanu 57 made their experiments in vitro withthe natural juices supplied to them by Pawloff. They found alsothat nucleotides were changed into nucleosides by intestinal juice,but that pyrimidine nucleotides were less affected than guanylicacid (guanine nucleotide) ; the nucleos ides (inmine, guanosine,cytidine) were not affected by any digestive juice.We may therefore conclude that during digestion the totalamount of cleavage is small.This brings us t o actual metabolic experiments and the investi-gation of the action of tissue extracts. Here I have six importantpapers to discuss, all emanating from America, some fromLevene’s and some from Walter Jones’s laboratory.I will takethem in chronological order.The first on the list, “Nuclein Metabolism in the Dog,” isby Levene and Medigreceanu.68 It deals with the effect seen in theurine as a result of feeding on nuclein and some of its cleavageproducts. When nucleic acid is given, 50 per cent. appears in theurine, of which 85 per cent. is in the form of allantoin, and therest as urea. I f thymus gland is given, 17 per cent. of the nitrogenis excreted as allantoin, 5 per cent. as uric acid, and the rest urea.Various purine bases were given, and certain nucleosides, such asinosine; varying fractions of the nitrogen in urea, allantoin,uric acid, etc., were obtained. These results clearly show that inspite of the small change produced in the alimentary canal, thenuclein group of substances are nevertheless broken down intosimpler materials somewhere in the body; it is obvious that thissomewhere must be in the tissues and organs.The same authors69 then proceeded t o investigate the varioustissue jnices, or plasmata, as they term them.It is only necessaryto give a few samples of their results. Plasma of hearbmuscle,liver, kidney, and intestinal mucosa hydrolyse inosine or hypo-xanthosine, giving rise to the free base and d-ribose; bld-serumand pancreas-plasma have no effect. Guanylic acid is hydrolysedby the same plasmata, with the addition of that obtained from thepancreas. Cytidine (cytosine + ribme) was not split by any plasmainvestigated, and the cleavage of nucleic acid from yeast was incom-plete.Such work at once demonstrates that various tissues may actin different ways, and indicates that the enzymes are numerous anddifferently distributed in the organs.s7 J. Biol. Chem., 1911, 9, 375 ; A . , ii, 744.j8 dmcr. J. Physiol., 1911, 27, 438 : A., ii, 303.5y J. Biol. Chem., 1911, 9, 6 5 ; A., i, 410204 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.This view was accentuated in the third paper I have to refer to,this time from the pen of Walter Jones.*O H e regards the use ofthe term nuclease as unsatisfactory if it is understood to mean anenzyme which liberates purine bases from nucleic acid, for thereis no assurance that the enzyme of one gland can decompose thenucleic acid of another organ.Although the nucleotide structureis common to all the nucleic acids, differences occur in the natureand number of their nitrogenous rings, and it would therefore besurprising if one enzyme can decompose them all, for the moreone learns about enzymes the greater appears to be their specificity.Illustrating this, he found that an extract of ox spleen will effectthe decomposition of the mono-nucleotide guanylic acid, but thatpig’s pancreas which is rich in other kinds of nuclease has no effecton this particular nucleic acid.As a further illustration of the multiplicity of the enzymicagent. at work, Jones in his next paper61 considers the case of thedeamidases, and shows that there are a t least four independentones. We must add to the adenase and guanase, which were knownbefore, two others, namely, guanosine-deamidase and adenosine-deamidase.Their actions are indicated by their names; thusadenase converts adenine into hypoxanthine ; adenosine-deamidaseconverts adenosine into hypoxanthonine ; guanase converts guanineinto xanthine ; guanosine-deamidase converts guanosine intoxanthosine. The enzymes acting on the amino-purines are distinctfrom those which act on the aminmmcleosides, because one groupis present in pig’s liver, for instance, and the other is not.The next contribution to the subject takes us back again toLevene and Medigreceanu.62 They accept the work of Jones, andof similar results obtained in Germany by Schittenhelm, and whichcoincides with their own results in regarding the gradual seriesof changes that occur in nucleic acid, as being due to the gradedaction of numerous and specific enzymes, and they classify thenucleases into three groups as follows :(1) Nucleinases, which resolve the molecule into mono-nucleo-tides; these occur in all organs, in pancreatic juice, but not ingastric juice.(2) Nucleotidases, which liberate phosphoric acid, leaving theribose-base complexes (nucleosides) intact.These also occur in allorgans, and in intestinal juice, but are absent in gastric andpancreatic juices.(3) Nztcleosidnses, which hydrolytically cleave the nucleosides6o J. Biol. Chena. 1911, 9, 129 ; A . , i, 410.62 Ibid., 1911, 9, 389 ; A,, i, 698.Ibid., 169 ; A , , i, 410PHYSIOLOGICAL CHEMISTRY.205into their components, ribose, and bases of the purine or pyrimidinegroups. These are absent in all the digestive juices, and in theplasma or tissue juice expressed from the pancreas, but are presentin varying degree in the plasmata of most other organs.I now reach the last paper on the question, and this is a verycomprehensive one by W. Jones and S. Amberg.63 These writersagain emphasise the points already noted relating to the multiplicityand specificity of the enzymes at work. To show the differencesbetween different organ extracts, let us take the following as aninstance. The pancreas and theliver of the pig were both employedto act upon nucleic acid. In the pancreas experiment, guanosinewas one of the end-products, but this nuclemide underwent nofurther cleavage ; adenosine was formed simultaneously, but thiswas deamidised t o form hypoxanthosine or inmine.In the experi-ment with pig’s liver, guanosine was not only deamidised to formxanthosine, but the xanthosine was further split into ribose andxanthine. At least nine enzymes are in this way called into play:(1) Phosphenuclease.(2) Purine nuclease.(3) Guanosine deamidase.(4) Adenosine deamidase.(5) Adenase.( 6 ) Guanase.(7) Xanthosine hydrolase.(8) Inosine hydrolase.(9) Xantheoxydase.We further see that this clears up another difficulty I alluded toin a previous namely, how does hypoxanthine occur inmuscle, seeing that adenase is absent from that tissue? The pro-visional answer given a t that date was that hypoxanthine in thissituation is “ preformed,’’ and is not directly connected withnuclein metabolism at all.We have now another possibility, anda much more probable one, and that is that adenosine is deamidisedto hypoxanthosine (or inwine) by the enzyme numbered (4) on theforegoing list; and this is hydrolytically split so as to yield hypo-xanthine by enzyme No. (8) on the list. Enzyme No. (5) in thiscase never comes in at all.Finally, let me attempt briefly to summarise:(1) Nucleic acids possess a common structure, namely, phosphoricacid combined with a carbohydrate (the pentose named riboae),which in its turn is united with a base.63 Zeitsch. phylsiol. Chem., 1911, 73, 407 ; A . , ii, 823.64 Ann. Report, 1910, 171206 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.(2) They differ from each other by such grouping being eithersingle or re-duplicated.(3) The general term nucleotide is adopted for the phwphoricacid-ribose-base complex.(4) Nucleic acids may be monenucleotides ; for instance,guanylic acid; but more usually the grouping is re-duplicated toform poly-nucleotides.(5) The bases obtainable from poly-nucleotides are adenine andguanine of the purine group, and bases of the pyrimidine group,such as cytosine.(6) I n the case of the pyrimidine basw, their union with riboseis possibly not glycosidic, and is firmer than in the case of thepurine bases.(7) When broken down by chemical reagents, the first changeis the removal of the phosphoric acid, leaving intact the combina-tions of ribose and base.(8) The ribose-base complexes are termed nucleosides ; thus :guanosine = guanine + ribose.adenosine = adenine + ribose.cytidine = cytosine + ribme.(9j The nucleosides may be split hydrolytically into base andcarbohydrate ; or they may be deamidised, and the correspondinghydroxynucleosides obtained; and these in their turn may by hydrolysis be broken up into base and carbohydrate; for instance,adenosine may be deamidised t o hypoxanthosine (also calledinosine), and this in its turn is split into hypoxanthine and ribme.(10) The same cleavages are aocomplished in the body by theaction of tissue-enzymes contained in varying degrees and kindsin the different organs and tissues.As these enzymes are specific,the number which may come into successive play in the decomposi-tion which occurs within the body is extremely numerous.Theseenzymes may be spoken of in a general way as nucleases. Theindividual names they have received indicate the particular act ofcleavage they perform.(11) The nucleic acids in the food are not affected by gastricjuice, and in the intestine such cleavage as does occur is limitedt o their separation into mono-nucleotides, and the partial conversionof these into nucleoslides by the splitting off of phosphoric acid.‘‘ Standard Bread.”“Some gave them white bread, and Borne gave them brown,”indicates the existence of a dilemma which caused trouble in pastages, and still continues to be a burning question. The advocates oPHYSIOLOGICAL CHEMISTRY.207bread made from the whole grain, or a t any rate from flour whichretains the germ, have received support from a section of the dailypress during the year; and the irresponsible writers who haveconsidered it their duty to boom what they have illogically termed“standard bread” are more remarkable for their zeal than fortheir knowledge. The very word ‘‘ germ ” is one to conjure with ;to many minds it suggests the germ of life, a sort of concentratedessence of all that is good. To those, however, who desire a soberstatement of facts rather than a hysterical presentment of crudeideas, I would recommend an article on the subject by ananonymous writer in a recent issue of Science Yrogress.65There is no doubt that the boom has been beneficial to certainmillers, who have been able t o sell at high prices inferior flourswhich would otherwise have been wasted.There is also no doubt that to the majority of people the choiceof white bread or whole-meal bread is altogether immaterial;it is purely a matter of taste t o those who live on an ordinary mixeddiet, and to whom bread is only one of the many articles of foodingested.Experiments on rats such as those published in preliminarycommunications to the weekly medical journals are wholly incon-clusive; still less convincing are the hastily compiled statistics byschoolmasters bitten with the craze.The only logical attitude taken up by a responsible person isthat assumed by Dr.F. hwland Hopkins, and that is that adecision is impossible in the present state of knowledge, and eventhen the decision will only affect those people to whom bread reallyis the staff of life.The homeopathists of the past, as is well known,used to prescribe drugs in such extremely minute doses that anyphysiological action would have been next door t o impossible. We,however, are now acquainted with substances such as adrenalineproduced in the body which produce powerful effects in doses muchsmaller than those of the homeopathists. Such materials mustultimately be formed from the food, so that very minute quantitiesof certain food materials may be important factors in the mainten-ance of health. The germ of the wheat grain is the part which willultimately grow when sown into the new plant, and it is quitepossible, as Dr.Hopkins has pointed out, that there may be certainsubstances elaborated by the living cells of the plant which cannotbe readily synthesised by the animal body. Their quantity cannotbe considerable, and if they are present, and their chemicalnature is entirely problematical, it may be that they arenevertheless of value. This is a perfectly feasible hypothesis,Ii5 ‘* The Ethics of Pootl. 111. Bread.” Scci~iice Proyrc,\s, 1911, 536208 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.and one hopes that some really conclusive experimental work maybe set in hand to test its truth. Those who say that whole-mealbread is richer in protein than white bread are speaking the truth,although the difference is not a large one.They forget, however,that chemical composition is never a criterion in itself of thenutritive value of a food. The nutritive value depends on theamount which is assimilated, and that again depends on digesti-bility, and that can only be determined by actual experiments. Tomost people whole-meal bread is not so readily digested as whitebread is, so that any increase in protein percentage is more thancounterbalanced by increased loss in the fceces. Even supposingall the protein in whole-meal bread was entirely digested and assimi-lated, no one can pretend that the small extra dme of nitrogenousintake can be of the superlative value attributed to it by some;the same end might equally well be obtained by an extra halfslice per diem of white bread.The difference is not a quantitativeone, but, if present, is qualitative, and the important substancein the germ, if there is one, is in all probability not protein innature.A piece of work which illustrates the importance of small amountsof certain food materials in nutrition with another form of food,namely, milk, may be referred to here as a case in point. W. Stepp 66fed mice on milk deprived of its lipoids; they soon died, but theaddition of the alcohol-ether extract to such milk prevented a fatalresult. Addition of the fats alone, or of lecithin or cholesterol tosuch milk did not delay the onset of death. Here, a t any rate, wehave some unknown substance present in quite small quant.ity, whichis nevertheless essential for successful growth and life.I have deliberately avoided as much as possible the employmentof the popular expression “standard bread,” for that term begsthe whole question, and assumes beforehand that bread of a certaincolour and made in a certain way is to be regarded as an idealfood.The use of adulterants in all foods should be prohibited bylegislation, and offenders should be severely dealt with who attemptto purvey on a credulous public any food to which something hasbeen added or from which something has been removed. It appearshopeless, however, in the present state of politics to attempt anylaw-making on subjects which affect the public health.Commis-sions are appointed, and their reports are pigeon-holed for years.The report of the Committee which dealt with food-preservativesten or twelve years ago is still a dead-letter so far ils enactments“The Importance of Lipoids i n Nutrition,” Zeitsch.Biol., ’911, 57, 135 ; A.ii, 1002PHYSIOLOGICAL CHEMISTRY. 209are concerned. The President of the Local Government Boardsession after session fails to bring to fruition his Pure Milk Bill.These questions unfortunately do not excite Party feeling, and sofall into the background, and Dreadnoughts still continue to bebuilt without any steps being taken for ensuring the health of thecoming generation who are to man them.That a standard in white bread is quite as necessary as one inbrown bread has been recently brought before the public by thereport published by Drs.Hamill and Monier-Williams.67 I n relationto the grosser forms of adulteration which they reveal there canbe no difference of opinion that these should be sternly prohibited.Whether bleaching by nitrous fumes is harmful to any seriousdegree is a moot point. There is some retardation of digestion,especially towards saliva and gastric juice, but the amount ofnitrite left in the flour is extremely minute, and in the bread madefrom the flour it is still further reduced.Another anonymous article on this subject in Science Progress (j*has appeared, and its author rather scorns the evils described,especially bleaching, and takes Drs. Hamill and Monier-Williamsto task for condemning such procedure. This I regard as a veryunsafe attitude to assume.Our knowledge of the effects ofbleaching is still in its infancy; the object of the miller is tosupply the public with what they ask for, namely, very white flour,and the consumer runs the risk of the flour being over-bleached,and therefore admittedly harmful, or of obtaining inferior flourmade to look like the best, so that the miller reaps a pecuniaryreward t o which he is not entitled.The striugent laws of t.he United States against the employmentof adulterants of this order meet with my entire sympathy, for ifthey err at all it is an error on the right side, as they prevent theintroduction of even the thin end of the wedge.The following brief extract from a judgment by Mr. JusticeWarrington in a case tried before him two years ago may be ofinterest.The case in question was one between rival patenteesin the matter of flour-bleaching.“Even Dr. Halliburton did not go further as a summary ofwhat he considered to be the result, than that the process of treat-ment by the plaintiff’s invention imposes on the human framejust one more of those extra burdens which the progress of civilisa-tion has from time to time imposed on the human frame. Many67 ‘‘ Reports to the Local Government Board on the Bleaching of Flour and theBy J. M. Hamill and G. W. Monier-See also in a more68 1911, 279.addition of so-called lmprovers to Flour.”Williams.condensed form, J. Rygiene, 1911, 11, 142, 167 ; A . , ii, 1001.Food Reports, No. 12 (Cd. 5613), No. 14 (Cd. 5831).REP.-VOL. VIII.210 ANEUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of us think that there are many modern improvements, the intro-duction of motor-cars, for example, which impose an extra strainon the human frame, but no one would pretend to say that apatent for the invention of a motor-car would not have been auseful invention for that reason. With regard to digestibility,it seems to me it is not a practical objection, and even if it ismade out that there is a scientific and theoretical action on theflour which may be said to be deleterious, there is no evidencethat there is any practical substantial deleterious result of whichI can take account.”That really is the crux of the whole question, and those interestedin public health will have to see in the future that the scientificobjection never becomes substantial and practical, just as someof our public authorities are attempting to minimise the dust,smell, noise, and other discomforts that attend the use of motor-omnibuses.Knowing as we now do the possible dangers whichmight ensue were millers allowed a free hand, it is necessary thatif bleaching is still countenanced a strict watch should be exercisedto keep its use within the limits of safety.Be&- b eri.Here we pass from one of the important questions of the Westto a somewhat similar problem which is mainly of Eastern interest.No hypothesis hitherto advanced with regard to the origin ofberi-beri (the kakkee of Japan) has up till now found sufficientexperimentaJ confirmation to warrant its general acceptance.Thisapplies equally t o the conception of the disease as due to thepresence of hacteria or other parasites, to toxins in the body orin food, or to c‘miasms.” One fact, however, stands out clearly,and is now generally admitted by investigators, namely, that thereis some connexion between the disease and rice. In all thoseEastern countries in which the disease is endemic, every suffererfrom beri-beri is a rice-eater, and conversely European residentswho eat little or no rice do not get beri-beri.During the Russo-Japanese war, very striking illustrations ofthe part played by rice in the causation of the disease came tolight. I take one only. During the siege of Port Arthur, theJapanese army and navy lived under exactly the same conditionswith one exception; in the army the old rice diet was still main-tained, but in the navy a reform had been introduced by addingto the rice a certain amount of either meat or barley.The diseasestill continued to decimate the soldiers, but the sailors escapedalmost scot-freePHYSIOLOGICAL CHEMISTRY. 211The rice consumed in Japan is mainly (‘white rice,” that is, ricefreed from pericarp and husk, and finally polished.A few years ago Dr. S. Kajiura, an officer of the Japanese Navy,worked in my laboratory, and undertook some experiments onberi-beri, or a t least on a very similar disease with characteristicneuritis and nerve degeneration, which can be artificially producedin fowls. These are naturally not the first experiments performedin this way, but exception has been taken to the results previouslypublished, because they were obtained in a possibly (‘ infected ”locality.Whatever objections there may be to King’s College, it,has the advantage of being free from any suspicion of harbouringberi-beri surreptitiously. The fowls fed on the white rice diedwithin a few weeks with the usual symptoms and postrmortemappearance of beri-beri.69 Kajiura in conjunction with Rosenheimhad previously made a study of the nature of the proteins in rice,7Oa cereal which, curiously enough, had escaped any previous examina-tion of the same kind; among the most noteworthy of their findingsthey ascertained that rice almost completely lacks a protein solublein alcohol, similar to the gliadin of wheat and rye, or the hordeinof barley.Thinking possibly that the absence of this protein mightexplain the harmful effect of an exclusive rice diet, they fed someof the birds on rice + hordein, and rice + gluten ; other animals hadadded to their diet calcium carbonate and calcium phosphate inorder to test the hypothesis advanced by others that lack of calciumor of phosphorus might be a t the root of the matter. But in nocase did they succeed in appreciably delaying the onset of death.Fowls fed on barley, however, showed no signs of the disease. Theexperiments were not sufEciently numerous perhaps, for Dr.Eajiura, had t o return to Tokio, but so far as they went theynegatived the suggestion that the lack of a gliadin in rice isresponsible for the production of beri-beri.With the small space still a t my disposal, I cannot attempt areview of the huge literature that has now centred around what isa national question for the Japanese.This will be found in certainpublications issued during the year by the Japanese Governrn~nt.~~I shall only deal, and that briefly, with three papers. The firstF9 Iiajiura. and Rosenheim, J. Hygiene, 19’10, 10, 49 ; A., 1910, ii, 635.7u Proc. physiol. SOC., 1908, liv ; J. Physiol., 36 ; A., 1908, ii, 317,71 “ lllitteilungen der 13eri- t!eri-Studien Kornmission,” Tokyo, 1911.Thispalm contains nnmerous references to other authors.The fullpaper will be published in the Bio-Chewa. J.“ Sanitiits-statistik der Japanischen Armee mit besonderer Beriichsichtigung der Beri-Beri inderselben,” Tokyo.‘‘ Japan und seine Qesundheits-pflege,” by Bintaro Mori, Tokyo, 1911. The last-named book treats of many othersubjects in addition to beri-beri and is a niost interesting work on Japanese history.‘ ‘ Kriegsministerium,” 1911.P 212 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of these deals with analyses of rice, and the economic value ofrice in the tropics; it is only indirectly related to the subject weare discussing, and an abstract has already appeared in ourJournal.72 The second merits .longer notice, because i t does, Ithink, bring us nearer to the solution of the question, and iswritten by two of our own countrymen working in the MalayStates.73 They find that it is the removal of the “polishings” ofthe rice that produces the harmful effects. The natives of theMalay peninsula who consume unpolished or slightly polished ricedo not suffer from beri-beri, but those who take polished rice do.Fowls’ fed on polished rice develop a form of polyneuritis analogousto beri-beri, whereas those fed on unpolished rice remain healthy.I f the polishings removed from the rice are added to polished rice,fowls fed on the mixture also remain healthy. The harmfulinfluence of white rice is not due to a poison developed in itafter milling, but to the removal of some substance of high physic+logical importance essential to the maintenance of health.The estimation of total phosphorus in any given rice indicatesthe extent of the milling or polishing to which it has beensubjected, and therefore of its power in producing disease. Thepolishings are much richer in phosphorus than the part of thegrain left behind. Rice containing 0.4 per cent. or more of P20,is safe.The essential substance or substances are still unknown ; theyare probably small in amount, but whether they act by renderingother constituents of the diet available for nutrition, or whetherthey are themselves the nutritive material necessary for nerve-tissues is a t present a matter of conjecture. The polishings arenot only richer in phosphorised constituents, but are Qomewhatricher in the alcohol-soluble protein than the polished rice. Theprotective substances, as they may be termed, are destroyed byheating the unpolished rice to 1 2 0 O . The fats contained in theperipheral layers of the grain are of no value as a protectionagainst polyneuritis. The protective substances are soluble in0.3 per cent. hydrochloric acid, but phytin, which comprises 32.5per cent. of the substances so soluble, is without value as a protec-tive. The protective substances are soluble in 91 per cent.acidulated alcohol, and exclusive of dextrose amount to not morethan 11 per cent. of the polishings, and not more than 1 per cent.cf the original grains. In this fraction the alcohol-soluble protein72 Arm and Hocson, Bioc7ietn. Zeitsch., 1911, 32, 189 ; A . . ii, 625.73 “ Studies from the Institnte for Medical Research, Federated Malay States,”No. 12. “The Etiology of 1Seri-Beri,” by Henry Fraser and A. T. Stanton.Singapore, 1911. 89 1)ag~’sPHYSIOLOGICAL CHEMISTRY. 213and compounds of calcium, magnesium, and phosphorus areincluded.This narrows down the search very considerably, and one hopesthat i t may not be long before the protective substance is fullyidentified, although one is naturally cautious in prophesying ; suchmaterials one knows by experience are often very elusive.The third and last paper to which I have to refer has beenpublished since the foregoing paragraphs were written, and containsan important fulfilment of the hope just expressed.74 Funk showsthat the protective substance present in the polishings and absentfrom polished rice is present only in minute amount, probably notmore than 0.1 gram per kilo. of rice. It is an organic base, anda crystalline nitrate was prepared from it, of which an elementaryanalysis was made. The figures are, however, given with caution,as the supply of materiaJ was too small for duplicate analyses. Thecurative dose of this material wits found to be extremely small.I f there is any value in arguing from analogy, it is quite possiblethat the outer portions of the wheat grain may also contain somematerial of special importance.W. D. HALLIBURTON.74 “ The Chemical Kature of the Substance which Cures Polynearitis in BirdsBy Casitnir Funk. J. Ph,ysioZ., 1911, 43, induced by a Diet of Polished Rice.”395

ISSN:0365-6217    

DOI:10.1039/AR9110800182

出版商:RSC    

年代:1911

数据来源: RSC

摘要:

AGRICULTURAL CHEMISTRY AND VEGETABLEPHYSIOLOGY.THE year 1911 has not been made noteworthy by the publicationof any paper of special value; nothing has appeared that can beclaimed as a new discovery, or that would indicate a fresh pointof view or a novel method of attack on the many complicatedproblems with which the agriculturist has to deal. It is, however,perhaps permissible to note that a steadily increasing volume ofsound scientific wosk is being turned out by British investigators.The agricultural colleges and departments are all occupying them-selves in research, and the quality of the work turned out shows adistinct advance from year to year. Were no other evidence forth-coming, this might be seen in the style of the papers and the discus-sio'ns on agricultural topics at the Portsmouth meeting of theBritish Association, which has now accorded the dignity of a fullsection tlo the subject of Agriculture.Attention may also be calledto the fact that the Board of Agriculture has published the outlinesof a scheme for the furtherance of agricultural research, which it isabout to set in operation by the aid of funds provided by theDevelopment Commission. According to this scheme the sum of&50,000 per annum is to be devoted to the prosecution of agricul-tural research, and it is proposed to establish for each of the maindivisions of the sub ject-animal nutrition, investigation of thesoil, plant chemistry and physiology, plant breeding, animal zoology,dairying, fruit growing, etc.-an institute to be attached to someexisting university or agricultural college, which will be sufficientlysubsidised to permit of the continued investigation of the funda-mental problems involved, irrespective of their immediate translationinto practice.The scheme further makes provision for grants toindividual workers not necessarily connected with the institutes,after the manner of the grants for scientific research administeredby the Royal Society, and also for the strengthening of the scientificstaffs of the existing agricultural colleges to enable them to under-take local investigations and to give advice to the agriculturistswithin their sphere of action. With this aid i t may be hoped that21AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY.2 15as the scheme gets into operation the United Kingdom will developa body of scientific workers comparable with thoee of other countriesand worthy of the position which agriculture still holds in thenational economy.Soils.During the year has been published the first attempt a t a system-atic soil survey of a portion of the British Isles, in the shape of areport on the agriculture and soils of Kent, Surrey, and Sussexby A. D. Hall and E. J. Russell.1 These authors have taken thegeological formations that are developed in that district as thebasis of their work, and conclude that each formation gives riseto a soil type which can be characterised both by the mechanicalanalysis of the soils and by the special features in the farmingprevailing over the out-crop.About sixteen different soils are dealtwit,h, ranging from the Lower Wealden to the Bagshot Beds,together with three drift formations, and for each of these soilsfrom ten to twenty analyses are given of samples taken fromdifferent parts of the area, both soil and subsoil being dealt with,and mechanical as well as chemical analyses reported. The authorsfind that the mechanical analysis alone provides a satisfactory basisfor classification. The chemical analyses have all too much incommon, and are too largely determined by the scheme of cultiva-tion under which the soil has been worked, although certain corre-lations are shown to exist between some features of the mechanicaland the chemical analyses, especially as regards the proportions ofalumina and potash.On the basis of the analyses and of theauthors’ acquaintance with farming practices in the district, recom-mendations are made as to the systems of manuring, etc., appro-priate to each formation. The report also cont,ains a series of mapsshowing the distribution of crops within the area, and in the textthese are correlated with the character of the soils. Finally, theinformation derived from the occurrence of particular crops indifferent parts of the area is gathered together to lead to conclu-sions as t o the nature and composition of the soil best suited towheat, barley, fruit, hops, etc., under the climatic conditionsprevailing, for it is shown that the variations of the rainfall havea considerable influence on the cropping best adapted t o a parti-cular type of soil.I n a further article2 the same authors discusssome of the more scientific questions on which the informationaccumulated in the report throws light. They give examples to“Agriculture and Soils ot Kent, Snrrey, and Sussex,” published by the Boardof Agriculture and Fisheries, H. M.tStationery Office, 191 1.J. Agric. J%i., 1911, 4, 182216 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.show the agreement which may be expected between the analysesof samples taken in different places on the same soil type, and howthese may be modified by local accidents which result in washing orflooding. They show again how other formations change in char-acter progressiveiy along or across the out-crop, owing to a changein the conditions under which the formation was originallydeposited.They then proceed to discuss the interpretation ofmechanical analyses and the relation they bear to climate andsituation. Complete mineral analyses are given of the variousfractions obtained by mechanical analyses, to illustrate the changeof composition in passing from t'he coarser to the finer fractions.These analyses also indicate the existence of two distinct types inthe material deterrhined by the mechanical analyses as " clay "; inthe more fertile soils theclay contains about 21 per cent. of aluminaand more than 50 per cent. of silica, whereas the clay from a groupof second-rate soils contained about 30 per cent. of alumina and lessthan 50 per cent.of silica. I n the discussion of the chemical analysesi t is shown how difficult it is to attach any significance to theabsolute amount of plant food contained in the soil; for example,the nitrogen, which is generally about 3 per cent. of the loss ofignition, may be associated with a rich soil or with a soil in whichthe conditions are so unfavourable that organic matter does notdecompose. It is shown that the amount of alumina soluble inhydrochloric acid is approximately equal to one-third of the clayfraction determined by mechanical analysis, and that the potashis commonly about one-tenth of the alumina, thus indicating thatthe hydrochloric acid must break down some definite group ofsilicates in the soil. A few soils show exceptions to this rule, allsoils possessing a special character marked by an exceptional pro-portion of fine silt.No correlation was found between fertilityand the lime-magnesium ratio, and the amounts of ferric oxidepresent were similarly non-significant. Wanganese was determinedin nearly all the soils, but no significance can be attached to theresults.Hall and Russell's work purports to be little more than a pre-liminary sketch, even for the district under examination, but i tdoes indicate the lines on which such work can proceed and whatreturns of practical and scientific value may be expected fromsystematic soil analysis, the value of which will increase with eachaddition to t.he number of analyses and to the area over which theyextend.It becomes obvious, for example, that little advice canbe given to the farmer on the strength of an isolated soil analysisunless the result can be compared with those of the type to whichthe soil belongs. It is the departures from the type that are signiAGBICIJ1,TURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 2 17ficant, and may provide the clue t o the solution of the difficultieswhich the farmer experiences with the soil.0. Lemmermann and his colleagues in Berlin3 report a numberof vegetatiod experiments with soils showing various limemagnesiaratios, but they have been unable to substantiate Loew’s opinionthat this ratio is of significance to the fertility of the soil, it conclu-sion which had also been reached by Hall and Russell in theirsurvey mentioned above.Lemmermann also proceeded to comparethe results given by analysis as to the amount of lime andmagnesia in the soil with the response of the same soils to dressingsof these substances in vegefiation experiments. They obtained veryinconclusive results wherever the amounts of lime were small ; inother words, determinations of the amount of lime in the soilgave little or no indication of whether the soil was in need oflime or not. It should be noted, however, that these authorsdetermined simply the lime soluble in dilute acid or in a solutionof ammonium chloride, whereas it has been often pointed outthat only the lime as carbonate in the soil can be of any signi-ficance in determining its fitness for plant nutrition, and thatrecourse must be had to one of the methods that will measureminimal amounts of carbon dioxide evolveld from the soil withoutdecomposing the organic matter, which in certain acid soils alsogives rise to carbon dioxide under the action of acid.A somewhatsimilar question has been examined by H. R. Christensen and0. H. Larsen.4 These aut,hors examined more than one hundredsoils, the need or otherwise of which for lime was known; they deter-mined the carbon dioxide set free by acids,the amount of calciumdissolved by an ammonium chloride solution, the behaviour of thesoil towards litmus, and, lastly, applied a biological test, in which5 grams of the soil were introduced into 50 C.C. of 2 per cent.mannite solution and inoculated with Azotobncter. Azotobacter willonly develop under these conditions when the soil contains calciumcarbonate, and the results yielded by this test were found to agreewith the known behaviour of the soil in 90 per cent.of the casestested, whereas the litmus reaction failed to agree in 40 per cent.of the cases, the ammonium chloride method in about half thecases, whilst the determination of carbon dioxide failed more oftenthan not to indicate correctly whether the soil was in need of lime.0. Schreiner and his colleagues, E. C. Shorey and E. C. Lathrop,in the Bureau of Soils of the United States Department ofLandw. Jnhrbuch., 1911, 40, 175, 255.Ccntr. Bakt. Par., 1911, ii, 29, 347.5 J. Bid. Chem., 1910, 8, 381 ; 1911, 9, 9 ; A., ii, 65, 327; J. Amer.Chem. Soc.,1911, 33, 1412; d., ii, 923218 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Agriculture have continued their investigation of the organicsubstances that can be isolated from soils, and have compiled along list of substances isolated in a pure state. Amongst acidsubstances they have obtained hydroxystearic, dihydroxystearic,picolinecarboxylic, agroceric, paraffinic, and lignoceric acids.Amongst protein cleavage products they find arginine, histidine,cytosine, xanthine, hypoxanthine, whilst C. S. Robinson 6 hasisolated leucine and isoleucine ; other substances identified arephytosterol, agrosterol, coumarin, and similar substances. All ofthese may be supposed to be derived from the decomposition ofplant residues by bacterial actions, and the authors appear to beabandoning the idea that was once put forward that they are directexcretions from the plant’s roots.Schreiner, however, still regardsmany of them as direct causes of unfertility; for example, he findsthat the presence of dihydroxystearic acid alm&l invariably accom-panies infertility in soils and is associated with conditions of poordrainage, lack of lime, and deficient aeration. Again he finds7that some of these substances have specific effects on plants;coumarin, for example, causes a peculiar distortion in the leaves ofplants when it is added to the nutrient solution in which theyare growing. Vanillin inhibits the development of roots, whilstp-benzquinone induces a specially tall and slender growth.Theseeffects can be inhibited by particular fertilisers ; for example, thepresence of phosphates prevents coumarin from taking effect, thevanillin action is overcome by nitrates, and that of pbenzoquinmeby potassium salts. Whilst such results, if they can be confirmedand extended from growths in water cultures to soils, wouldlend support to the theories of fertiliser actions which are asso-ciated with the American Bureau of Soils, they seem slenderevidence against the conception of the direct nutritive action offertilising substances. R. G. Smith8 has also examined soils fortoxic substances, and he has been able to extract from them abacter&oxin soluble in water and filterable through porcelain,which inhibits the growth of bacteria.This substance is destroyedby heating, sunlight, or storage, and its existence in soils might beappealed to in order to explain some of the results obtained byRussell and Hutchinson and by Pickering. Russell and Hutchin-son’s original investigations, theref ore, took into account the possi-bility of such an inhibiting substance, but showed by crucial experi-ments that its removal cannot be the factor causing the increaseof fertility of soils after they have been heated or exposed to thefi .J. Amer. Chem. SOC., 1911, 33, 564 ; A . , 3, 431.7 Proc. Amer. SOC. Biol. Chem., 1910, xiii.8 Proc. Linn. SOC., AT.S. Wales, 1910, 35, 808AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 219vapour of antiseptics. R. G. Smith has also investigated the waxyand resinous substanca which can be extracted from soils, andfinds that they may form a waxy coating on the soil particles whichcauses them to be less readily attacked by water and bacteria. Thepossibility that the accumulation of material of this kind in soilswhich have been long.under cultivation and heavily dressed withorganic manures, might cause the characteristic difficulty in wettingsuch socalled worn out soils when dry, has been considered byother observers, but it has never yet been demonstrated that theremoval of such material by ether, etc., causes any difference in themanner in which water will move in the soil.Amongst other investigators of the organic constituents of thesoil may be mentioned A. G. Dojarenko,g who has investigated theproducts of the oxidation of humic acid with hydrogen peroxide.He finds that compounds containing nitrogen as amide and amino-acid pass into oxidised forms of humic acid, such as apocrenic acid,whilst the humin-nitrogen is transformed into simple amides andammonia. Dojarenko suggests that this method may serve todiscriminate between the nitrogen in the soil which is stable andthat which is likely to become available for plant nutrition whenthe organic matter is oxidised.Several investigations are reported on the colloid substances inthe soil and the part they may be supposed to play in its behaviourtowards water and fertilisers, but nothing very definite has yetemerged, and the results are hardly suitable for abstraction.J.Konig 1" and his co-workers describe a method for the estimationof this colloid matter by determining the amount of methyl-violetwhich a given weight of the soil can withdraw from solutions of1, 2, or 3 per cent.strength, according to the character of the soil.The method has not yet received sufficient trial to determine itspractical value, but it is one of easy application, and as it promisesto afford a simple measure of one of the most important factors in thephysics of the soil-the extent of the active surface of the particleswhich is very imperfectly gauged by methods of mechanicalanalysis, it may be recommended for further examination to anyonewho is engaged on the analysis of a large number of soils. I n thedomain of soil physics an interesting paper has appeared by W.H.Green and J. A. Ampt,ll in which they describe a simple form ofapparatus for determining the permeability and capillary constantsof soil, on which both the movements of air and water through soildepend. The apparatus is such as can be readily fitted up andi' 7th Int. Congr. App. Chem., 1909, VII, 11 ; A., i, 357.lo Lnndw. Yersuchs. Stat., 1911, 75, 377 ; A . , ii, 1033.l1 J. Agric. Xci., 1911, 4, 1220 ANNUAL REPORTS ON TEE PROGRESS OF CHEMISTRY.manipulated in an agricultural laboratory, and it is now necessaryto ascertain if the constants thus determinable will prove ofpractical value in interpreting the behaviour of soils when a largenumber of soils of varied types come to be examined.Soil Bacteriology.Although a very large numker of papers have been publishedon this subject, nothing very striking or suggestive has arisenduring the year; in fact, most of the papers rather leave a feelingof volume and diffuseness than of clear conclusions that can beadapted to the interpretation of soil conditions in nature.Whilst it is easy to trace the great changes that are being broughtabout by bacteria in the soil, as, for example, the mobilisation ofthe nitrogen reserves and the preparation of them for the higherplants, i t is difficult to bring these changes with their mutual inactionwithin the sphere of quantitative measurement.The methods whichhave been so far devised for measuring the power of the soil t o effectany particular type of change seem to be vitiated by the entirelyartificial conditions under which the soil is placed in the laboratory,and the great desideratum a t present is a system of measuring theactivity of the soil in a manner that will agree with results obtainedin situ.As to the general bacterial activity in the soil,R. Emmerich and his colleagues 12 have described certain experi-ments in which the addition of starch a€3he rate of 0.6 per cent.to a loamy soil brought about a considerable retardation of growth,the roots of the test plants turned brown and to a large extentdied off, This injurious action is attributed to the enhancedbacterial activity in the soil brought about by the condition of thecarbohydrates. An excessive number of bacteria acts harmfullyon the roots by withdrawing oxygen and so depressing their powersof assimilation, and also by the formation of hydrogen s-ulphide inthe de-oxygenated atmosphere of the soil through the reductionof sulphates by the bacteria.The roots, in fact, become chokedbecause they cannot compete with the bacteria for the restricted airsupply. H. B. Hutchinson and F. S. Marr 13 report some similar butearlier experiments, in which the application of starch and sucroseto the soil of certain of the Rothamsted experimental plots resultedin a marked reduction of the yield. Examination of the soil afterthe application of the carbohydrate showed a great increase in anumber of bacteria and moulds there present; in one case thebacteria increased in number after the treatment from about 6.4 to14.9 millions per gram of soil.Certain experiments in pots confirmedl2 G'sntr. Bakt. Par., 1911, ii, 29, 668 ; A., ii, 430.l3 7th Id. Cong. App. Chein., 1909, VII, 37 ; A . , ii, 430AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 221these trials in the open. Such results would seem to contradict thehypothesis that an increase of nitrogen in the soil will follow asupply of carbohydrate because of the activities of nitrogen-fixing organisms like Aaotobacter. The &%ion of Azotobacter isnormally limited in soils by the lack of carbohydrate, from thecombustion of which the A eotohacter derives the energy necessaryto bring the nitrogen into combination. The explanation of theseanomalous results has since been found in the fact that the carbehydrate was supplied to the soil in the spring a t the time whenit is at such a low temperature that other bacteria, for example,some of the simple putrefactives, are far more active than Azoto-bnctey.I n later experiments the carbohydrates, starch or sugar,have been supplied to the same plots in the autumn directly afterthe removal of the crop; the, soil is then warm, Azotobacter isactive and can utilise the carbohydrate, with the result thatsufficient nitrogen is fixed to produce an undoubted increase ofcrop in the following season.The action of the nitrogen-fixing organisms, and particularlyAzotobacter, continues t o be the subject of investigation. One ofthe points that has hitherto been somewhat difficult to understandis the comparatively high rate of fixation which some of the fieldresults would appear to indicate, as compared with the smallamounts of nitrogen obtained in a combined state in laboratoryexperiments, in which 10 milligrams of nitrogen fixed for each gramof carbohydrate' destroyed are rarely exceeded.A. Koch and 8.Seydel14 have investigated this question in asomewhat novel fashion, in that after the infection of a dextrosesolution with Bzotobacter they determined from day to day theamount of nitrogen fixed and also the amount of dextrose that hadbeen oxidiseci. Under these conditions they found that in theearlier days there is a very much higher ratio between the amountof nitrogen already fixed and the dextrose oxidised, as high, in fact,as 50 or 60 mgm.of nitrogen per gram of dextrose. The authorsattribute the falling off in the later stages of fixation to theaccumulation of nitrogenous materia.1 in the medium, whereupon theorganism begins to employ the carbohydrate for other purposes thanfixation. I n the open ground this aocumulation and concentrationof nitrogenous material by the Azotobacter itself is not likely tooccur, so that they consider that the organism will continue fixingnitrogen at the higher ratios indicated in the earlier stages of theirexperiment.T. Remy and G. Rosinglj have also investigated the reasons forthe greater effectiveness of Azotobacter in soils than under labora-l4 Centr. Bakt. Pal-., 1911, ii, 31, 570. l5 Ibid., 30, 349 ; A., ii, $58222 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.tory conditions, and they find that with cultures in soil extractsthe presence of humus stimulates the action of Asotobacter.Thisstimulus they attribute to the smali quantities of iron and similarsilicates that the humus contains. They also found that the valueof ferric iron for the development of Azotobacter very much dependson the form of combination in which it is supplied. Ferrichydroxide dissolved in sucrose is perhaps the most effe$ive form,but ferric silicates are also valuable. It is to the presence ofsoluble substances of the latter class in basic slag that they aredisposed to attribute some of the very beneficial effects which basicslag has been noticed to have on the development of Azotobacterand the fixation of nitrogen.Some very remarkable effects of Aeotobacter are reportedfrom Colorado. There W.P. Headden has previously indicatedthe existence of certain soils which develop sometimes in smallpatches and a t others in considerable areas, and become abso-lutely sterile through the accumulation of salts and particu-larly of nitrates in the surface soil. In a bulletin16 publishedduring the year a det'ailed examination is given of twenty-twoexamples of such soils. The analyses are remarkable; the soilis always brown and mealy in texture, and contains an unprecedentedamount of material soluble in water; for example, in one case thetop foot contains as much as 1.127 per cent. of soluble material,of which 23 per cent.consisted of nitrates calculated as sodiumnitrate. The top inch and a-half of this soil contains as muchas 5.5 per cent. of material soluble in water, more than half beingnitrates, and Headden calculates that an acre of the land downto the depth of 13.5 inches contains no less than 30 tons of nitrates,principally sodium nitrate. The author shows that the presenceof these substances cannot be put down to surface water bringingnitrates from a distance and accumulating them by evaporation ;in nearly all cases the land is reasonably elevated, the sterile spotsbeing no lower than the surrounding country; it is well drained,and the water table never near the surface. The natural watersin the district do not contain any exceptional amount of nitrate,nor does the water used for irrigation.The brown spots develop insome cases with great suddenness, and the crops either grow verybadly or not a t all; established orchards which existed in mostof the cases examined are rapidly killed outright as soon as thebrown patches appear. All the appearances indicate that theexcessive amount of nitrate is the cause of death, as, for example,the intense green of the foliage, followed by scorching at the edgeand tips of the leaves, and the author was able to reproduce thel6 Agric. Exp. Sta., Colorado, 1911, Bull. 178AGKICULTUKAL CHEMISTRY ASD VEGETABLE PHYSIOLOGY. 223effects by the employment of excessive amounts of sodium nitrate.The origin of these large quantities of nitrates Headden sets downto the fixation of nitrogen by Szotobacter and its rapid nitrifi-cation afterwards, and he shows that laboratory samples of thesesoils when placed under favourable conditions of incubation fixexceptional amounts of nitrogen, as much as 10.5 milligrams per100 grams of soil in twenty-seven days.M7. G. Sackett17 under-took the bacteriological study of the soils, and was able toestablish the fact that they were able to fix nitrogen, whenincubated in a damp condition and without any addition ofcarbohydrate, a t a very exceptional rate, sufficient to accountfor the nitrates found in the soil, provided that nitrificationkept pace with fixation. Azotobacter chroococcum was the dominantnitrogen-fixing organism in the soil, and the brown colour so charac-teristic of the sterile patches was shown to be due to the pigmentdeveloped by this organism.When the nitrates accumulate to theexceptional extent indicated in some of the soils, fixation ceases,and the Azotobacter may even be killed off. Saturation of the soilwith water also limits the fixation of nitrogen. These results arevery remarkable, and so far as we are aware have not beenparalleled anywhere else. The point that is not yet clear is whencethe Azotobacter derives the energy necessary to bring such quanti-ties of nitrogen into combination, but the prime fact that in thesesoils sterility is due to an excess of nitrogen and particularly ofnitrates, seems t o be fully established, an extraordinary result whenwe remember that under ordinary conditions of agriculture allover the world the difficulty is to obtain sufficient nitrogen andnitrate t o get the soil up to its maximum fertility.H.Pringsheimls has added to the number of baoteria which areknown t o fix nitrogen by isolating from ordinary garden soil certainthermophilic organisms which fix from 3 to 6 milligrams of nitrogenper gram of dextrose destroyed. The soil is incubated with aWinogradsky solution containing a little soil extract a t a tempera-ture of 61°, whereupon only a few bacteria proved t o be capable ofdevelopment at this temperature, and these fix nitrogen in themanner indicated.No particularly novel work in connexion with the beneficialeffects of heating and partiaI sterilisatim of the soil is reportedthis yea.r, although several investigators have published papers ofthe effects of carbon disulphide, ether, and similar substances onthe bacterial content of the soil.They generally ignore the issuethat has been so definitely raised by Russell and Hutchinson, andAgyic. Exp. S t t s , Colorado, 1911, Bztll. 179.It: CCTL~T. UnEt. Par., 1911, ii, 31, 23 ; A., ii, 916224 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.fall back on the hypothesis of stimulus by the antiseptic to theorganism, although Russell and Hutchinson described criticalexperiments which put such explanations out of court.T. Goodey,lg working a t Rothzmsted, has published descriptionsof the vsrious protozoa to be found in cultivated soils, and alsorecounta a method for driving these organisms out of the soil andenumerating them without having to go through the process ofcultivation.This method is valuable, because it is rarely possibleto pick up the organisms by a microscopic examination of the soilitself, still less to enumerate them. Goodey’s paper goes on toadduce evidence that the ciliated organisms, at any rate, must bein an encysted condition in the soil under normal conditions, andtherefore incapable of carrying out the function of limiting thenumber of bacteria with which they were credited by Russell andHutchinson. There still remain other organisms like ameba, towhich this objection does not apply, but in all probability thebacteria themselves are functioning but slowly in the soils asexamined by Goodey; hence the two sets of organisms come intoacbivity simultaneously when the conditions of moisture and tem-perature are favourable, and the ciliated protozoa may still playtheir part of limiting bacterial activity in the soil.E. J .Russell and J . Golding20 have issued a first report on thebearings of the protozoa theory on sewage-sick soils. They find thatthe soils on land which has been over-watered with sewage are swarm-ing with protozoa, but possess to a very limited degree the bacterialactivity by which the purification of the sewage should be effected.Treatment with lime had no beneficial effect on such soils, but apartial charring of the surface soil or treatment with variousantiseptics restored at once its power of purifying the sewage.Coincident with this came an enormous increase of the number ofbacteria present in the soil; for example, in one case the sewage-sick soil contained only 40 million bacteria per gram, but aftertreatment and when the land was, again functioning in thepurification of sewage, the numbers rose to 400 million per gram.S.Suzuki 21 and A. J. Lebedeff 22 have continued the very interest-ing stadies initiated by Beyerinck on the production of gaseousnitrous and nitric oxides from nitrates by various reducing organ-isms, and have added to our knowledge the conditions under whichone or other of these gases are produced. Suzuki obtained onlynitrous oxide with the materials that he examined, whereas Lebedeffl9 Proc. Eoy. Soc., 1911, €3, 84, 165.2o J.SOL.. Chem. I t i d . , 1911, 30, 471.21 Cent. Bakt, Par. , 1911, ii, 31, 27 ; A . , ii, 916.Ber. Dcut. bot. Ges., 1911, 29, 327 ; A . , ii, 917AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 225obtained abundant nitric oxide, sufficient in some cases to givebrown fumes when the gas evolved came in contact with the air.M. C. Potter 33 describes a very interesting set of experiments inwhich the disintegration of organic compounds by micro-organismsbecomes a source of electrical energy. A special form of cell wasconstructed, in which one platinum electrode was in contact witha nutritive solution, for example, dextrose, and the other in contactwith the same nutritive solution containing also an organism suchas yeast. A difference of potential was a t once established, of theorder of from 0.3 to 0.5 volt, and the electrical activity wasparallel to the activity of the yeast as measured by the carbondioxide evolved.C.T. Gimingham 24 has published an investigation into the forma-tion of calcium carbonate through the oxidation of calcium oxalatein plant residues by soil bacteria. It had previously been shownthat oxalates are capable of further oxidation to carbonates by thebacteria contained in soil, and Gimingham attempted to obtainpure cultures of the organisms. There is no difficulty in bringingabout the change by a crude culture obtained by inoculatinga little garden soil into an aqueous extract of soil to whichcalcium oxalate has been added, but the isolation of the organ-isms presented some difficulty, as also attempts to induce purecultures of various oxidising bacteria to attack the salt.I nthe end it was found necessary to develop a strong active cultureof the organism in a medium containing very little organiccarbon, as the organisms only attack the carbonate when theyhave exhausted the more available organic matter. Some ofthese organisms were isolated by dilution methods, and each ofthem, when heavily inoculated into a flask containing sterile soilextract and calcium oxalate in suspension, produced after a timecrystals of calcium carbonate on the walls of the flask. Theorganisms are all aerobic, but in view of the number that were foundcapable of effecting the change, specific differentiation did notappear t o be necessary.A number of well known organisms werealso examined in a pure state, none of which, except Azotobacter,could oxidise the oxalate.Chc.m&try of t h e Growing Plant.The mechanism of assimilation continues to attract the greatestamount of attention. As to the actual chemistry of the process bywhich carbon dioxide and water are transformed i n h sugars andProc. Roy. Soc., 1911, B, 84, 269 ; A . , ii, 913.z4 J. Agric. Sci., 1911, 4, 145.REP.-VOIA. VIII. 226 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.oxygen, J. Stoklasa and W. ZdobnickQ25 obtained a sugar by theaction of nascent hydrogen on carbon dioxide in ultra-violet light.I n the presence of pot'assium hydroxide formaldehyde was produced,and the action did not proceed without the ultra-violet rays. Thenature of the sugar was not determined, but a crystalline osazonewas obtained, melting at 196--200°.G. Inghilleri26 sealed up atube containing a 40 per cent. solution of formaldehyde withcrystalline oxalic acid, and exposed it to sunlight for fourteenmonths, at the end of which period he obtained a crystalline carbo-hydrate, which was optically inactive and was assumed from itsphysical properties to be sorbose.One of the most important questions connected with assimilationwithin the green leaf itself is the order in which the different carbo-hydrat'es are produced. I n most plants starch is the product ofthe action of light most readily recognised, but Brown and Morrissome years ago brought evidence to show that sucrose is the firstvisible product of the assimilation process, and that the starchresults from a secondary transformation in the leaf.The starchis further removed during the absence of light and accumulated insome other part of tlhe plant in various forms-sucrose, starch,inulin, etc. The plant must be regarded as capable of bringingabout a number of enzymic transformations that can as yet hardlybe paralleled in the laboratory. Moreover, the leaves of manyplants show the presence of dextrose, hvulosse, and maltose, andthe question arises whether these sugars are to be regarded asdown-grade products of the sucrose and starch first formed, orwhether they are up-grade products preceding the formation of themore complex carbohydrates.J.Parkin 27 has examined the question afresh, working with theleaves of the snowdrop, which contain no starch although bothstarch and inulin are stored in the bulb. I n the leaves of thesnowdrop he found only sucrose, dext8rose, and lzvulose, maltosebeing absent, and the total sugars may amount to as much as30 per cent. of the dry weight of the leaf. During the early partof the seaon there is more sucrose in proportion to reducing sugarsin the leaf than later, but during any single day the percentageof reducing sugar remains fairly constant, although the sucroseincreases during the day and diminishes during the night. As arule, the lzvulose is present in excess of the glucose. Parkinconsiders that his result supports Brown and Morris' theory thatsucrose is the first recognisable carbohydrate ta appear in the leaf,25 Rioehem.Zeitsch., 1911, 40, 433; A . , i, 175.p6 Zeitsch. phys~ol. Chem., 1911, 71, 105 ; A., i, 354.27 Biochem. .J., 1911, 6, 1 ; A., ii, 1127AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 2 27a.nd that the hexose sugars arise from it by hydrolysis precedentto translocation, although the results are not contradictory of thehypothesis that the hexose sugars are first formed. Parkin pointsout that Strakosch in 1907, working by microchemical methods,was able t o recognise dextrose only in the mesophyll, the lzevulosoand sucrose only occurring in the veins and still more in the midriband petiole. Sugar determinations in the cut-out tissue supportedthe view that dextrose is the first sugar to be formed by photo-synthesis and then travels from the mesophyll to the small veins,where it is in part transformed into lzvulose.The two hexosesthen combine to produce sucrose, in which form the carbohydratetravels to the storage organs. Certain determinations, as yet unpub-lished, on the fluctuation of the carbohydrates of the leaf takenat two-hourly periods during the day and night would rather agreewith Strakosch’s theory, indicating that the first effect of lightis a slight rise in the proportion of reducing sugars which remaincoristant at this somewhat higher level during the whole daylight;the rise in sucrose occurs a little later, and in its turn isfollowed by a continuous rise in the proportion of starch as longas the daylight lasts.The maltose, on the contrary, reaches itsmaximum during the night and its minimum during daylight,thus indicating that maltose is a down-grade product from thestarch, which would agree with Yarkin’s failure to find maltosein the snowdrop leaf, where starch is also absent. More numerousand exact da€a are certainly wanted, especially as the quantitativediscrimination of the sugars in leaf tissue presents a number ofexperimental difficulties, but the question is an important one,because until it can be decided which sugar is the first product ofphotosynthesis, it is difficult to speculate its to whether the earlierstages be@ with the formation of formaldehyde or not.R. Willstatter 2b and his colleagues have continued their impor-tant studies of chlorophyll and its derivatives, and have revised someof their earlier conclusions.They find that crystallised chlorophyllcontains one ethoxy- and one methoxy-group, not two methoxy-groups as before stated, and that amorphous chlorophyll containsone methoxy- and one phytyl group. The figures previously givenfor the proportion of amorphous chlorophyll in the leaf are too low,because during the extraction of t’he leaf enzyme actions convert theamorphous into the crystalline chlorophyll if the process of extrac-tion is a t all slow. The change is due t o a specific enzyme, chlorephyllase, which belongs to the group of esterases and can beextracted separately from the leaf.Willstatter describes methodsof rapid extractions of the leaf which yield a much higher product28 Annalen, 1910, 378, 1, 18, 73; 1911, 380, 148, 154, 1 7 7 ; A . , i, 140, 659.Q 228 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of amorphous chlorophyll than before. Willstatter further describesthe relationship of chlorophyll to its derivatives. The fundamentalacid from which they are all derived is a trjcarboxylic acid of theformula C?3,H29N4Mg(C0,H),, which he terms chlorophyllin. Themonomethyl ester obtained by hydrolysis of Chlorophyll he callschlorophyllide ; then amorphous chlorophyll is phytyl chlorophyllide,and crystalline chlorophyll is ethyl chlorophyllide. The synthesisof chlorophyll from chlorophyllide and phytol can be effected bythe enzyme above mentioned, but the yields are small.Otherpapers deal with the derivatives of chlorophyll, including thosewhich contain no magnesium.Further progress has been made of. the study of the remarkablechanges brought about by chloroform, toluene, and similarsubstances on the living tissues of the plant. I n continuation oftheir former work, H. E. and E. F. ArmstrongZ9 show that theleaves of Aucuba japonica when expoeed to the action of volatileorganic vapours such as toluene, chloroform, or ether, becomerapidly a rich chocolate-brown and ultimately black. The action ofthe excitan6the hormone, as the authors term i&is to liberatethe enzymes of the cell, whereupon glucosides are hydrolysed andoxydases are rendered active, the blackening of the leaf tissuebeing in all probability an oxidising action.Acid solutions andmost salts are incapable of starting this action in the leaf, butmercuric chloride, cadmium iodide, sodium and potassium fluorides,carbon dioxide, hydrogen sulphide, and ammonia penetrate theleaf and initiate the changes. I n a later paper the authors pointout that the translocation of substances like sugars in the plant isperiodically taking place a t some times and not a t others, and thattherefore the cell wall must be alternately permeable and imperme-able. This change in the permeability in the cell wall might bebrought about by the action of hormones. In particular they showthat the Aucuba leaf when exposed in water containing one of thehormones allows reducing sugar to pass out from the leaf into thewater, although if placed in pure water no such diffusion of thesugar takes place.I f the hormone used is hydrogen cyanide, thechanges within the leaf take place, but no sugar passes out, whichseems to show that the different hormones are not alike in theiraction on the differential septa of the living tissue.A further very interesting series of observations in this subjecthave been published by I. Giglioli,So who attributes the action ofthe chloroform and other vapours, among which he particularlyAnn. of Botany, 1911, 25, 507; A . , ii, 642; Proc. Eoy. SOC., 1911, B, 84,Atti R. Accad. hincei, 1911, [v], 20, ii, 349 ; A, 1912, ii, 79.226 ; A., ii, 918AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY.229instances the essential oils of the various aromatic plants, to thechanges which these vapours bring abou6 in the surface tensionof water. He took sand and various soils saturated with waterand drained them until they yielded no further water, then exposedthem to the vapours in question. The sand or soil immediatelyparted with more water; for example, in one case with coarse sandas much as 31 per cent. of the water that was previously retainedexuded from it under the action of chloroform vapour. With soilsproper the exudation was not so great because of the imperfectpenetration of the vapour into the homogeneous soil. The sameexudation of water took place from vegetable tissues; for instance,two thick fleshy leaves of the Cactus opuntea were placed separatelyin a moist atmosphere, one being exposed also to the vapour ofchloroform.I n twenty-one days the chloroformed leaf lost 23 percent. of its weight in liquid which transuded from the wholesurface of the leaf, whereas the non-chloroformed leaf lost lessthan 4 per cent. Moreover, as in the Armstrongs’ experiments, aconsiderable amount of soluble material passed out with thetransuding liquid frcm the chloroformed leaf, amounting at theend of the experiment to 20 per cent. of t h s dry weight of theleaf, whereas the transuding liquid from the non-chloroformed leafcontained only an insignificant proportion of soluble material.Giglioli extended these observations to yeast, and showed thatordinary dry yeast when exposed to the vapour of chloroform,eucalyptus oil, and other volatile oils, rapidly softened and lost itjsstructure until a quantity of clear liquid could be filtered off fromit.This liquid was a solution of the enzymes of the yeast, andproved to contain both zymase and invertase, so that it wouldinduce an alcoholic fermentation in solutions o€ sucrose or dextrose.Giglioli suggests that this may prove the readiest method ofobtaining zymase from yeast. It is evident that the action of thevolatile oils which many plants excrete must exercise some profoundregulative effect on the movements of water and of translocatingsubstances within the plant, but until more data accumulate i t isdifficult to speculate on the exact nature of the function.It isa t any rate significant that the most highly odorous plants aregenerally those growing in dry, arid situations, and again that withmany plants there is a sudden and considerable liberation of volatileoil with the advent of evening and the failing of the light.The part played by excitants in starting some of the primephysiological changes in the plant is further illustrated by someexperiments reported by P. Maz6.31 H e finds that if seeds of maizeand peas are taken from the plants in an unripe condition, when31 Compt. r e d . , 1910, 151, 1383; A., ii, 141230 ANNUAL REPORTS ON THE PROGRESS OF CHEMTSTRY.they still contain from 50 to 60 per cent. of water, they cannot bemade to germinate under sterile conditions, although they willsometimes do so in ordinary soil; whereas if the seeds are dried,germination will take place.Maz6 finds the unripe seeds containa small amount of acetaldehyde which inhibits germination, thismaterial being removed by the drying process or by the action ofcertain bacteria and micro-fungi associated with the soil. Thequestion of possible excretion from the plant root is still a matterof controversy, and G. Andr632 has attacked it afresh by makingestimations of the total quantitly of inorganic constituents containedin the experimental plants during different stages of the growth.His results lead him to the conclusion that by osmosis alone thepiant never parts with any of its salts, either from the dead leavesor by excretions from the roots.P. &Iaz6,33 however, comes toalmost exactly an opposite conclusion from experiments with maize,and concludes that both organic and inorganic salts are excretedfrom the roots and stomata.It has been assumed that if a plant is supplied with an unlimitedamount of the nutrient it requires in the food solution in contactwith the roots, it is a matter of indifference what concentration thesolution may possess. Such an assumption is, in fact, one of thebases of Whitney and Cameron’s theory that all soils are sufficientlysupplied with mineral plant food to satisfy the utmost requirementsof the plant, and they quote certain old experiments where plant’smade complete growth in nutritive solutions of extreme dilution.I. Pouget and D. ChouchakS4 have grown seedlings in watercultures containing different amounts of phosphoric acid.I n theirexperiments the assimulation of phosphoric acid by the plant wasin direct proportion to the strength of the solution, when the con-centration of phosphoric acid lay between 1.1 and 4 milligramsper litre. At lower concentrations, however, no such directrelationship was observed; both the growth and the amounts ofphosphoric acid taken up were more irregular. Experiments of asimilar nature have been made at Rothamsted, which tend to showthat the concentration of the nutrient solution is a factor in therate of growth in plants, even although the plant may be continu-ously bathed in a renewed solution of the nutrient, thus agreeingwith the Russian investigators that plants cannot make theiroptimum growth when supplied only with an excessively dilutesolution of nutrienl, even although the total amount of plant foodavailable may be in excess of the plant’s requirements.33 Co’iiiyt.rend., 1910, 151, 1378 ; A . , ii, 141.:73 Ihid., 1911, 152, 452; A . , ii, 324.sq J. Buss. Exp. Landw., 1910, 11, 825AGRICULTURAL CHEMISTRY AND VEGETAELE PHYSIOLOGY. 231H. B. Hutcliirison and N. H. J. Miller 35 have continued theirinrstigation of the compounds of nitrogen which can be utilisedby the plant. Their experiments were made in water culturesunder sterile conditions, and at the close the culture media weretested to rnake quits certain that no infection had taken placewith bacteria which could break down the nitrogenous compounds.Despite the experimental difficulties attaching to such work,Hutchinson and Miller succeeded in growing a large number ofplants which remained sterile until the end of the trial, and theseproved to utilise a much larger range of nitrogen compounds thanhad hitherto been considered possible.Earlier experiments haddemonstrated that, ammonium salts can be freely taken up, andneed not be first of all converted into nitrates. Of the compoundstested, ca.rba.mide was most freely utilised, then came barbituricacid, acetamide, alloxan, soluble humus, and peptone ; thenformamide, glycine, alanine, guanidine hydrochloride, cyanuric acid,osamide, and hydroxylamine hydrochloride were utilised in smallquantities, whereas ethyl nitrate, propyl nitrate, methyl carbonate,a.nd also probably trimethylamine, p-urazine, and hexamethylenedi-amine gave negative results.Tetranitromethane proved to be toxic.Although in the soil, activity of the nitrifying bacteria is so greatthat the products of the bacterial attack on complex nitrogenousbodies are converted into nitrates before they reach the plant, itis yet evident that this final change is not necessary, and that theplant, may, and, in fact', must in certain circumstances, derive itsnitrogen from the less oxidised compounds formed a t the earlierstages of the bacterial cleavage which is always going on in the soil.MaiLzcres and Mumring.An increased amount of attention is being given to the methodof conducting field experiments; the limitations and the probableerror attaching *to the method are1 being considered in theirbearing on the interpretation of the results obtained.With thegreat extensions of field trials, both of manures and varieties ofcrops, which have taken place during the last few years, and thecontradictory results that are often reported with the most diverseexplanat,ions, i t has often been felt that undue discredit was beingbrought on the value of such work, even when i t only consisted inthe demonstration of known principles, by the failure of theexperimenter to recognise the magnitude of the error to whichsuch work is subject', and the means by which such error can bereduced to a practical amount.35 Centr. Bakt. Par., 1911, ii, 30, 513; A ., ii, 920232 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.T. B. Wood and J. A. Stratton 36 have discussed their whole theoryof the error attaching to determinations and experiments of anagricultural character, and show how the validity of the conclusionsmay be tested by statistical methods. They begin by showing howa series of analytical determinations of such inevitable variablematerial as is afforded by growing crops can be checked by theconstruction of frequency curves so as to ascertain whether thematerial is homogeneous and whether the mean result can betrusted to give the desired information. They further apply themethod of least squares in order to obtain the probable errorattaching to the mean result, and then proceed to discuss theresults obtained by weighing up an apparently uniform acre ofmangolds in plots each 1/1000th of an acre in area.The resultswould show that the probable error of a single plot amounts toabout k 5 per cent. of the total, and is not reduced by makingthe plot larger, so that the most accurate way of obtaining a validresult is to set out a number of similar plots of small size for eachmethod of treatment adopted.On similar lines W. B. Mercer and A. D. Hall37 discussed theresults obtained at Rothamsted by weighing up an acre of mangoldsin 200 equal plots and an acre of wheat in 500 plots. Theresults were then combined to give the yield from larger plots ofvarious sizes and shapes, and the probable error calculated in eachcase.Mercer and Hall find about the same probable error for asingle plot as Wood and Stratton, but further show that the errordiminishes with the size of the plot, although the reduction issmall when the plot is larger than 1/40th of an acre. They alsoshow that the error may be diminished by increasing the numberof plots under similar conditions, provided the plots are scatteredabout the experimental area, although again the reduction in erroris small when the number of plots is increased above five. Theyfinally recommend that the unit of comparison in each experimentshould be five plots, each of 1/4Oth of an acre and systematically dis-tributed about the area under experiment. It is to be hoped thatthese papers will lead to an improvement in the method of con-ducting field experiments by the many local authorities who under-take this kind of work, so that the results accruing may possesssome permanent value and be utilisable for further investigation.As regards manures in general no very novel work is reported.The various fertilisers containing nitrogen obtained from theatmosphere continue to be tested, but the main principles of theiraction may be considered as settled except in the one case ofartificial calcium nitrite, which, although not on the market in a36 J.Agrdc. Sci., 1910, 3, 417. 37 Ibid., 1911, 4, 10’7AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSZOLOGY. 233commercial form, might be produced in place of nitrate should itprove an equally valuable source of nitrogen. Various tests con-tinue to be made with finely ground minerals containing phosphoricacid or potash, to ascertain if these substances can replace the presentmore expensive fertilisers which have been subjected to chemicaltreatment of some kind; for example, T.Remy 38 has comparedfinely ground raw Algerian phosphate with basic slag. In hisexperiments it gave but poor returns; its effectiveness was onlyabout 5 to 10 per cent. of that of an equal amount of acidsuperphosphate, whereas basic slag had a comparative effectivenessof from 64 to 76 per cent. The returns from ra.w phosphates differ,however, with different crops; with blue lupins much the mostfavourable result was obtained. The use of finely ground phonolitehas also been advocated as a source of potash in place of theStassfurt salts, but in very few of the numerous results reporteddoes this material yield to the plant any satisfactory amount ofpotash, and it is not likely to become a commercial fertiliser aslong as the comparatively concentrated Stassfurt salts retain theirpresent cheapness.TV. H.Hervey 39 reports 5 number of analyses of soot, a fertiliserin very common use in England, but likely t o be variable in corn-position. The samples examined showed varying percentages, from2.7 up to 5.5 of nitrogen, with exceptional cases of only 0.5 in thesoot from a tall boiler shaft, and of as much as 11 per cent. in thesoot from a kitchen chimney. Speaking generally, it was found thatthe content in nitrogen was higher the lower the weight per bushelof the soot.Practically the whole of the nitrogen in the sootconsisted of arr,monium salts.A. D. Hall and N. H. J. Miller 40 report some further studies ofthe ammonia contained in the atmosphere. In their experimentsdishes containing glycerol and water with a little sulphuric acidwere exposed at various heights above arablb and grass land for aperiod of two years, monthly determinations being made of theamount of ammonia absorbed. Care was taken to exclude flies anddust as thoroughly as possible, and under these conditions verymuch smaller results were obtained than those reported by otherworkers who have used similar methods. The dishes a t higherlevels always absorbed rather more ammonia than those near theground, although this may be due to the better circulation of thoupper air.The monthly absorption of ammonia was much the samein the winter and the summer months except near houses, wherethe winter results are definitely higher, probably owing to the con-38 Landzo. Ja,hrb., 1911, 40, 559.40 Ibid., 1911, 4, 5 6 ; A., ii, 763.:% J. Agric. Sci., 1910, 3, 398234 ANNUAL REPORTS ON THE PROGRESS OF CHENJSTRP.sumpt.ion of coal. The authors conclude that the method is nota satisfactory one for the study of the amount of ammonia containedin the atmosphere, nor do the results lead to a definite conclusionas to whether the soil is normally emitting or absorbing ammonia.They found, however, that a large increase in the ammonia absorbedclose to the ground followed the application of ammonium saltsas a fertiliser to the soil of the field above where the dishes wereplaced, hence a loss of ammonia is indicated from the soil to theatmosphere whenever the amount of free ammonium compounds inthe soil becomes large.The fungicidal action of the Bordeaux mixture is discussed in apaper by B.T. P. Barker and C. T. Gimingham,41 who draw theconclusion that it is due to the action of solid precipitated coppercompounds on the hyphz of the ,parasite as they attempt to spreadover the surface of the leaf, and not to any liberation of solublecopper compounds by the actdon of atmospheric carbon dioxide onthe precipitated salt. I n a further paper Gimingham controvertsPickering’s idea that the value of Bordeaux mixture can be measuredby the amount of soluble copper i t will yield to carbon dioxideand water, because such a method postulates the action of purecarbon dioxide on the precipitate. The precipitated copper salts ofBordeaux mixture, whether basic sulphate or carbonate, do notyield any appreciable amount of soluble copper when exposed to theaction of the atmosphere, because of thevery low tension of carbondioxide in such atmosphere.The amount of copper which passes intosolution is, in fact, a function of the tension of the carbon dioxidewith which the material is in contact, so that to submit the mixtureto the action of pure carbon dioxide and water gives rise tomisleading results.Chemistry of A nimnl Nutrition,.This subject has suffered a severe loss during 1911 in the suddenand unexpected death of Oscar Kellner, which took place as hewas attending the meeting of the Union of Agricultural ExperimentStations a t Karlsruhe. Kellner’s work at Mockern, which placedhim a t the head of the investigators of the nutrition of agriculturalanimals, his wide experience of agricultural conditions in variouscountries, ancl his powers of exposition, helped to render his ideasacceptable both t o scientific and practical men.Kellner’s chiefcontribution to the theory of animal nutrition is the conception ofthe starch equivalent, a single figure which sums up the value ofthe food to the animal from the energy point of view when alldl J. Agric. X c i . , 1911, 4, 76AGRICUL'rURAL CHEMISTRY AXD VEGETABLE PHYSIOLOGY.235deductions have been made both for the portions of the food thatare not digestible and the energy which is spent by the animal inbringing about the digestion, and Kellner's careful experimentalwork succeeded in bringing into close agreement the experimentalvalues of the starch equivalents of the foods examined and thosededuced from its composition. Kellner had many friends in GreatBritain, where his genial presence will be missed.No very novel papers have appeared during the year, althoughF. Gowland Hopkins has described some yet unpublished workwhich promises to have considerable significance in the theory ofnutrition. He 1ia.s found that his experimental animals wereunable to thrive on an unlimited artificial diet containing modelproportions of pure proteins, fat.carbohydrates, and salts, andwould even die on such it diet if persisted in. The addition of veryminute traces, however, of various fresh extracts of animal orvegetable materials, milk, etc., to the diet enabled the animals toutilise it fully, although only an imperceptible increase in theamount of nutrient material as ordinarily measured was thusmade. Now that the gross requirements of the animal in the wayof energy and nitrogen supply have been established with a reason-able amount of accuracy, it is clear that the next step in estimatingthe practical value of different kinds of foods must be to obtaina knowledge of the small quantities of certain constituents over-looked in an ordinary analysis, but which by their action instimulating certain physiological functions of the animal may beall-important t o its power of utilising food.Amongst other papers A.Morgen42 and his colleagues atHohenheim have re-investigated the effect on their food value ofdrying green fodders like grass. It is usually considered, on thestrength of old experiments, that no change in the digwtibilitytakes place, and that hay, for example, is as valuable a food as thegrass from which it was made. These investigators find that such isnot st'rictly the case; there is some slight loss of material duringthe drying process which may become large with bad methods ofharvesting, and further, a slight falling off in digestibility, whichis probably due to physical hardening of the tissues, necessitatingan increase in the energy spent in digestion.F.Tang1 and A. Zaitschik 43 have examined the effect of wateryfoods on the secretion of milk, a question which has excited someinterest in this country. They fed their test cows with greenlucerne, beet, potatoes, marrows, etc., and reached a consumption ofwater in the food as high as 54 lbs. per diem per 1000 lbs. liveweight. The animal, however, proved to be capable of regulating42 Landw. Yersuchs-stat., 1911, 75, 321. 43 &id., 74, 183236 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.its milk secretion against such changes in the diet, and no variationsin the composition of the milk followed the change from a com-paratively dry to a watery diet.Their evidence is against thepossibility that is often presupposed of adulterating the milk throughthe mouth of the cow.I n connexion with the chemistry of food-stuffs, F. W. Foreman44has hydrolysed the protein of liaseed, a protein which, despite itsimportance in practical feeding, has hitherto escaped attentionbecause of tho difficulty of obtaining a pure product from the highlymucilaginous seed. The pure protein proved to contain 17.45per cent'. of nitrogen, and yielded, on hydrolysis, 1.03 of alanine,12-71 per cent. of valine, 3-97 per cent. of leucine and isoleucine,2-05 per cent. of proline, 4-14 per cent. of phenylalanine, 1-65 percent. of aspartic acid, 11.55 per cent. of glutamic acid, 0.65 percent. of tyrosine, 6.06 per cent. of arginine, 1.66 per cent. ofhistidine, 1-19 per cent. of lysine, and 1-94 per cent. of ammonia;glycine, serine, and tryptophan were also found. The exceptionalfeature about this analysis is the very high percentage of valine,of which not more than 2 or 3 per cent. has been obtained fromother proteins.M. Nierenstein 45 has investigated the nature of the nitrogenouscompounds present in ripe cheese, and incidentally throws lighton the claim often made that the ripening process resulh in theproduction of fat from the proteins of the cheese. Amongst theproducts of the ripening process of Cheddar cheese he findscholesterol, cadaverine, putrescine, and aminovaleric acid, sub-stances which are soluble in ether and account for the increasedweight of the ethersoluble extract of the ripe cheese which hashitherto been regarded as fat. Making allowance for these sub-stances, no evidence was found of fabformation from protein inthe ripening process.Attention may be drawn to a very useful summary and discussionby H. P. Armshy46 of a question to which allusion has frequentlybeen made in these Reports, namely, that of the utilisation of thenon-protein nitrogenous compounds of f od-the amineacids andamidee-which of late years has been a subject of a considerableamount of investigation. Armsby points out very clearly hhat theexperimental results obtained can be divided into two classes. Withcarnivora and herbivora these non-proteins are merely oxidised inthe organism, and cannot in any way replace the proteins. Withruminants, however, the nitrogenous compounds are converted by44 J. Agrie. Sci., 1911, 3, 358 ; A . , i, 341.45 PTOC. Boy. SOC., 1911, B, 83, 301 ; A., ii, 326.4tj U.S. Dept. Agric. Rurenu Animal Ind., 1911, Bull. 139AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 237bacteria in the digestive tract int.o proteins, which afterwardsbecome digested and may serve for maintenance and for theproduction of milk and growth when the rations are deficient inprotein. Ammonium salts and asparagine are more effective thanvegetable extracts, but in all cases the non-proteins are muchinferior to protein in nutritive value. Armsby’s article sets out themany difticulties in the investigation of these intricate questionsvery clearly.A. D. HALL

ISSN:0365-6217    

DOI:10.1039/AR9110800214

出版商:RSC    

年代:1911

数据来源: RSC

摘要:

MINERALOGICAL CHEMISTRY.THE year 1911 has been remarkable for the gaps it has left inthe ranks of the workers in Mineralogical Chemistry. The deathof J. H. van’t IIoff in March last, will be felt as an irreparable lossto this as to other branches of science. The brilliant researchecon salt deposits, vhich he happily lived long enough to complete,will stand as one of many enduring monuments of his gpius. Anappreciation of hls work in this field, from the pen of H. E. Boeke,has recently been published.1 Notable figures have also passedaway in A. Michel LQvy a.nd M. H. N. Story-Maskelyne, thelatter the doyen of our science; a bibliography of his writings and ashort memoir have appeared in the Mineralogical Maynzine.2Among other workers we have to depiore the loss of E.Hussak,N. V. Ussing, and G. Spezia.The work that has been accomplished during the year, althoughlarge in volume, makes little call for special comment. The newminerals described have not been numerous. The most interesting,perhaps, are fermorite, an analogue of apatite containing arsenic;hinsdalite, a sulphato-phosphate of aluminium and lead ; andthortveitite, a silicate of scandium. Of the researches which havethrown light on the composition or constitution of known species,those relating to the clintonite group, to nepheline, schwartzember-gite, tilasite, parisite, and pearceite are among the most important.Considerable activity continues to be displayed in the study of thephysical-chemical problems which have bearings on mineralogy.Some of these will be noted below; we will only here call attentionto the work on the tercary systems C‘aO-Al,O,SiO, andAg C1-AgB r-AgI .Two important new publications have appeared during the year,I n the first place, we have to welcome Vol.I of a periodical entitled“ Fortschritte der Mineralogie, Kristallographie und Petrographie,”published by the newly-formed German Mineralogical Society. I nit will be found excellent summaries of recent progress in crystallo-graphy and mineralogy. The article on the application of theFortschritte der Mineralogie, Kristallographie ?Lnd Petrographie, 191 1, 1, 285.Nin. Mag., 1911, 16, 149.23MINERALOGICAL CHEMISTRY. 239phase rule to mineralogical problems, and the review of advancesmade in our knowledge of meteorites since 1900, will be foundworthy of special attention.The notes on new minerals describedsince 1898 lose much of their value in the absence of any referenceto the original sources. The second publication is an ambitiouswork entitled “ Handbuch der Mineralchemie,” edited by C.Doelter, assisted by a number of contributors. It seeks to give acomplete survey, not merely of our knowledge of the composition ofminerals, but also of the best methods of analysis and other cognatetopics. The plan of the work is excellent, but to judge by the fourparts which have so f2r appeared, and which are devoted mainlyto the treatment of the carbonates, its usefulness is likely to bemuch impaired by careless editing. Misprints, mis-spellings ofproper names, and false references are irritatingly frequent, andtend to shake the confidence of the reader in the general accuracyof the work.We may now proceed to the detailed treatment of oursubject, following in the main the order adopted in past years.General and Physical Chemistry of Miner&Silicate Fusions.-In the first place, we must notice that thetemperature determinations made up to the present by Day andhis colleagues a t the Geophysical Laboratory in Washington havebeen recalculated in terms of the nitrogen thermometer, and a tableof corrected values has been drawn up.3 The melting points ofdiopside, anorthite, and labradorite are now given as 1391°, 1550°,and 1477O respectively. Albite melts below 1200°, and the changefrom a-quartz t.0 @-quartz takes place a t 575O.A ternary system,lime-alumina-silica, has also been studied in this laboratory.4 Ithas already been shown that both the met& and ortho-silicates ofcalcium can be obtained from the lime-silica fusion, but no indi-cations of the existence of t’ricalcium silicate were observed. Ithas now been discovered that this compound if4 readily producedwhen alumina is added to the limesilica mixture of the propercomposition. This substance, which has been isolated in the nearlypure state, appears to be unstable at its melting point. It doecjnot form either eutectics or solid solutions with calcium orthosilicateor with lime. A new, and probably unstable, form of calciumorthosilicate has been discovered; and it has been shown that ferricoxide dissociates at about 1400O with formation of Fe,04, and doesnot form solid solutions with lime, tricalcium silicate, calcium ortho-silicate, or wibh 3Ca0,A1,03.These researches have an importantA. L. Day and R. €3. Sosman, Amer. J. Sci., 1911, [iv], 31, 341 ; A., ii, 496.E. S. Shepherd, G. A. Rankin, aud F. E. Wright, J. Ind. Eng. Chern., 1911, 3,211 ; A , ii, i 2 5 240 ANNUAL REPORTS ON THE PROGRESS OF CHEMLSTRY.bearing on the Portland cement industry. Several other workershave also been active in this field; thus E. Dittler 5 has discussedthe difficulties met with in finding the heating and cooling curvesof silicates, and using Doelter's methods, has performed illustrativeexperiments on diopside and on certain felspars, both natural andartificial.He points out that, owing t o the small velocity offusion, the absorption of heat a t the melting point is not the chieffactor in determining the shape of the heating curve. The valueshe adopts f9r the, temperatures at which the crystallisation ofanorthite and labradorite begins are some 350° lower than the melt-ing points given above. Another interesting research, which we oweto the same author: had for its object the study of the influence ofthe addition to orthoclase of small quantities of its lithium, rubidium,and caesium analogues. It was found that czsium had the greatesteffect in increasing the stability of the orthoclase and in promotingits crystallisation, which appears to take place at comparativelylow temperatures, 750-800O.I f larger quantities of the rubidiumor czesiurn compounds were employed, the mass ceased to be homo-geneous, and different kinds of crystals separated. From this itmay be inferred that miscibility can only take place within quitenarrow limits. Mixtur- of orthoclase and celsian and of orthoclasewith andesine were also examined.Some experiments with mixtures containing orthoclase have alsobeen carried out by C. Ne~bauer,~ who finds that in the case ofmixtures of artificial leucite, orthoclase, and diopside, melting beginsabout the fusion point of orthoclase, and ends a t a temperatureabout the mean of all three melting points. On studying thecrystallisation phenomena, he finds that the freezing points arelower than the melting points of any 01 the constituents, and thatleucite crystallises out first, followed by diopside.Crystals oforthoclase are not formed.These, however, are not the only silicates which have been studiedfrom this point of view. H. S. van Klowter,* in the course of anexamination of a number of binary mixtures, has studied thesystem Li,O-SiO,. He finds that both ortho- and metaAlicates oflithium are formed, and that the two compounds are but slightlymiscible. The melting point of the former he gives as 1243O, thatof the latter as 1188O. These values are very close to the figures,1215O and 1180°, given by Rieke and Endel1,Q who have studiedZeitsch. anorg. Chem., 1911, 69, 273 ; 2., ii, 96.Tsch. Min.Mitt., 1911, 30, 118.7 Fiild. Kodo~iy, 1911, 41, 197.8 Zcitsch. a?zo.q C'hem., 1910, 69, 135 ; A., ii, 111.It. Rieke arid K. Endell, APreclmm?, 1910, 43, 682 ; 44, 97 ; A . , ii, 490, 982MINERALOGICAL CHEMISTRY. 241the same problem. Yet a third valLze has been obtained for themelting point of lithium metasilicate by F. M. Jaeger,lo who makesit 1201-8O, that of the corresponding sodium salt being 1088O.The existence of lead metasilicate as a, stable compound has beendeduced by P. Weiller 11 from a study of the lead oxide-silica system.He failed to find evidence for the existence of the orthosilicate, andhis results are not altogether in harmony with those previouslyobtained by Hilpert and Nacken.12 The conditions of formation ofthe silicat,es of manganese have been examined in the same way.13Manganosite, MnO, was observed among the crystalline products,as well as tephroite, Mn,SiO,, and rhodonite, MnSiO,.The eutecticbetween the two latter lies at 1190O. The mutual relations betweenthe components of binary mixtures of silicates of different metalshave also been subjected to thermal analysis. It has been shown,for instance, that MgSiO, (m. p. 1535O) and MnSiO, (m. p. l2lo0>form a series of solid solutions, with a break at 1328O and 50molecules per cent. of MgSiO,. Crystals rich in magnesium showthe properties of enstatite, those rich in manganese resemblerhodonite. Calcium metasilicate, CaSiO, (m. p. 1512O), forms acontinuous isomorphous series of mixed crystals with the meta-silicate of barium, BaSiO, (m.p. 1438O). The freezing-point curvehas a minimum at about 35 molecules per cent. of BaSiO, and1 0 0 O O . Mixtures of the silicates of barium and manganese andof calcium metasilicate with calcium sulphide have also beenin~estigated.1~In this connexion it may be noted that R. B. Sosman15 hasstudied the published analyw of pyroxenes and pyroxenibe rocks,and has plotted the results on a diagram representing a three-component system composed of MgSiO,, CaSiO,, and FeSiO,. Hefinds that the rock analyses lie in a limited " eutectic field," withthe rhombic pyroxenes on one side and the monoclinic pyroxeneson the other, and he considers that the relations observed are inharmony with the experimental data of Allen and White.Salt Fusions-It is not, however, among the silicates only thatthe study of cooling curves has led to results of mineralogicalimportance, for a number of other binary systems have beenexamined, some of which demand attention here.Italian workers 16have been particularly busy in this field, and to them we owe ourlo J. Washington h a d . Sci., 1911, 1, 49 ; A . , ii, 981.l1 Chem. Zeit., 1911, 35, 1063 ; A., ii. 983.l2 See Ann. Report, 1910, 227.l 3 F. Doerinckel, Metallurgie, 1911, 8, 201 ; A., ii, 608.14 P. Lebedeff, Zeitsch. anorg. Chem., 1911, 70, 301 ; A., ii, 604.lB J. Washington Acad. Xci., 1911, 1, 54 ; A . , ii, 992.-See papers by Sandonnini and others in Atti R. Accad. Lincei, 1911, [v], 20.REP.-YOL. VIII 24.2 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.knowledge of the behaviour of mixtures of a number of chlorides ofunivalent and bivalent metals.Some of the bivalent chlorideshave also been examined by 0. Menge,l7 whilst W. Botta 18 has madea study of the system NaCl-AgCl. He finds that the solidificationpoints of mixtures of silver chloride and salt vary continuouslybetween that of the pure silver compound melting a t 460° andthat of salt melting a t 792O. The crystalline masses which resultappear to be homogeneous. The mineral huantajayite, containing11 per cent. of silver chloride, may be regarded as a member of thisseries.These results have been confirmed by C. Sandonnini,lg who hasalso found that if lithium chloride is substituted for salt, two kindsof crystals are obtained.I n the hope of throwing some light on the nature of the mixedsilver halides which occur as minerals, F.MatthesZ0 has made avery complete study of the complex relations of the ternary systemAgC1-AgBr-AgI. His results lend no support to the view thatiodobromite, 2AgC1,2AgBr,AgI, exists as an independent species,for no compound of all three components could be got from themelt. Two kinds of mixed crystals were, however, obtained. Thefirst form a continuous series, and consist almost entirely of silverchloride and silver bromide, with quite inconsiderable quantities ofsilver iodide. The second are ternary mixed crystals, and containsilver iodide as an essential constituent. Pure silver iodide wasnot observed as it product; in any of the melts.The compositionsof the iodembolites analysed by Prior and Spencer are not inharmony with the results of these experiments, and it is suggestedthat their crystals were not perfectly homogeneous, but may haveconsisted of a core rich in silver chloride and bromide, surroundedby a shell containing more silver iodide and bromide. The ternarysystem formed by the three halides of lead has also been studiedby the same author.The conditions under which mixed crystals of sodium andpotassium sulphates are formed, both from fusions and from aqueoussolutions, have been examined by R. Nacken.21 He has found thatwhen fused mixtures are cooled, hexagonal modifications of thesalts separate first, which form a complete series of mixed crystals.As the temperature falls, these crystals undergo change, but theproduction of hexagonal mixed crystals identical with those result-ing from aqueous solution at low temperatures is confined to certainl7 Zeitsch.anorg. Chem., 1911, 72, 162 ; A . , ii, 982.lY Atti 8. Accad. Lincei, 1911, [v], 20, i, 758.2o Jahrb. Min. BciZ. Band, 1911, 31, 342; A . , ii, 476.‘L1 Satzungsber. K. Akad. llriss. Berlin, 1910, 1016 ; A., ii, 109.Centr. Min., 1911, 138 ; A., ii, 293MINERALOGICAL CHEMISTRY. 243concentrations, the limits being glaserite, Na2S0,,3K,S0,, on theone side, and 49 per cent. of potassium sulphate on the other.From aqueous solutions containing excess of potassium sulphate,glaserite and potassium sulphate separate, but when exceas ofsodium sulphate is present, mixed crystals composed of glaseritewith sodium sulphate occur, together with the latter salt.Growth'and Solution of Crystals.-It has long been known thatthe presence of irr,purities in the solution of a crystallisable sub-stzncs will influence the habit of the crystals which separate.Anotable instance of this is found in the behaviour of salt, which isobtained in cubes from pure aqueous solution, but appears inoctahedra from solutions to which carbamide has been added.Some light has lately been thrown on this curious phenomenon bythe determination of the rates of solution of salt on natural andartificial faces when exposed t o the action of unsaturated saltsolutions of various strengths.22 The rate of solution was found tovary with the degree of under-saturation.Moreover, when watercontaining salt only was used, material was removed slightly fasterfrom the octahedron faces than from those of the cube, but whencarbamide was added to the solution, this relation was reversed.Observations on growth and solution have also been made onother substances; thus, in the case of gypsum,2s the velocity ofsolution varies considerably on different faces, the relative valuesfor tha three common forms, {OlO}, {110}, and { l l l } , being1 : 1.76 : 1.88 respectively.In the case of the alums,24 the habit .may be considerablyinfluenced by adding hydrochloric acid t o the solution. If a littleis added, the forms (211) and (201) appear; further addition ofhydrochloric acid causes (201) t o increase. The behaviour ofmeconic acid and of artificial crystals of barytes 26 has also beenstudied from the same point of view, and it has been &own thatthe power possessed by some salts of taking up organic dyestuffsis an absorption phenomenon.27Transformation of Polymorphous Sub stances.-Somewhat dis-cordant statements are current aa to the heat-change which accom-panies the transformation of aragonite into calcite, and SLS t o thetemperature a t which the change takes place.It would nowappear that the temperature of transformation lies between 465Oand 470°, a sudden change in the density of aragonite occurring22 A. Ritzel, Zeitsch. Kryst. &fin., 1911, 49, 152 ; A., ii, 488.S. Tottoczko, Bull.Acad. Sci. Cracow, 1910, 209 ; A., ii, 24."A Z. Weyberg, Chem. Zentr., 1910, ii, 1026 ; A., ii, 263.P. Gaubert, Compt. rend., 1910, 151, 1134 ; A., ii, 101.26: H. Gerhart, Tsch. &fin. Mitt., 1910, 29, 185 ; d., ii, 262.27 R. Marc, Zeitsch. yhysikal. Chem., 1911, 75, 710; A . , ii, 193.R 244 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.about this point.98 Measurement of the amounts of heat given outon cooling calcite and aragonite which had been heated to varioustemperatures led to the conclusion that +2*72 cals. per gram-molecule represents the heat-effect of the change. This numberagrees with that obtained by Favre and Silbermann. Theresults of thermal analysis have established the existence of twokinds of quartz, termed a-quartz and &quartz respectively, thereversible transformation from one form into the other taking placeat 575O.The indices of refraction of quartz have lately beendetermined at various temperatures, ranging from - 140° to + 765O,and the existence of these varieties is confirmed by the discoveryof a well-marked break a t 57Oo.z9 I n the case of leucite, a substancewhich is birefringent at the ordinary temperature, but becomes iso-tropic at 7 1 4 O , the refractive index curve alters its direction; itshows, however, no sudden discontinuity, the change taking placeover a considerable temperature interval.Water of Crystallisation.-A few years ago F. Zambonini so con-tributed to the pages of an Italian periodical a very voluminousdiscussion of the part played by water in minerals.He has latelypublished in German a full abstract of this work.31 His contentionis that we must distinguish between water of constitution orcrystallisation on the one hand, and dissolved or absorbed wateron the other. He maintains that it is possible to make this dis-tinction with certainty by studying the course of dehydration. Asthe result of numerous experiments, he concludes that manyminerals, formerly believed to contain water of constitution, reallycontain absorbed water, and that many substances, such, forexample, as prehnite and apophyllite, contain variable quantitiesof dissolved water in addition to water of constitution.Some very interesting observations on the passage of waterthrough certain crystals containing water of crystallisation havebeen made by H.B. Baker and G. H. J. Adlam 32 during the courseof an investigation into the constancy of composition of such sub-stances. Phosphoric oxide was placed in small flasks, which werethen closed by crystal plates sealed into their mouths with paraffin.Flasks closed with plates of anhydrous crystals, such as anhydrite,CaSO,, potassium chlorate, or telluric wid, showed no change inweight after exposure to a moist atmosphere for some weeks. Onthe other hand, flasks closed by plates of gypsum, or of hydratedcopper sulphate, barium chloride, and potassium ferrocyanide2’J 1’. N. Lnschtschenko, J. Ems’. Phys. Chem. SOC., 1911, 43, 793 ; A . , ii, e86.m F. Itione and R. Kolb, Ja7~rb.Min., 1910, ii, 138 ; A . , ii, 209.Atli I?. Aecnd. Sci. Fis. Mat. A-apoli, 1908, 16, 1-127.31 Zeilseh. Kryst JfiH., 1911, 49) 73.s2 TraTls., 1911, 99, 507MINERALOGICAL CHEMlSTRY. 245showed very perceptible increases, proving that in these cases waterhad been transmitted by the crystal.Pressure and Chemical Change.-Van Hise has suggested thatunder the influence of very high pressures, silicates may be formedfrom silica and carbonates, water may be squeezed out of hydratedminerals, and combined oxygen may be removed in the same way.G. Spezia 33 has attempted to confirm these views experimentally,but without success. Thus calcium carbonate and hydrated silicadid not react when subjected t o a pressure of 6000 atmospheres fora year. Limonite, alabaster, and alum, exposed to a pressure of 8000atmospheres for eight months a t 15--24O, were not dehydrated, norwere crystals of gothite affected by keeping them for twenty-sixdays under a pressure of 9500 atmospheres.Calcite and aragoniteremained unchanged after exposure to a pressure of 7000 atmo-spheres for six months.Chemical Crystallography .The two most important investigations undertaken in this fieldduring 1911 are the study of the isomorphism of indium andthallium made by R. C. Wallace34 and the elaborate examinationof derivatives of the quaternary ammonium bases which we oweto A. Ries.36 The salts of the type K3T1C1,,2H,0, of which fivewere examined, crystallise in the holohedral class of the tetragonalsystem. Thme of the type Rb,T1Cl,,H20 are orthorhombic andisomorphous with the potassium and ammonium salts of thesame type containing iron.KT1Br4,2H,0, (NH4),TlBr4,2H,0,RbT1Br4,H,0, and CsT1Br4 are all cubic. So far as habit is con-cerned, the alkalis stand in the order: ammonium, rubidium,oaesium. Chlorine and bromine salts are very similar. On theother hand, the substitution of iron or indium for thallium producesmarked changes. The angles vary in a slightly different order,ammonium salts lying between those of rubidium and caesium, butnearer t o the former. The substitution of caesium for rubidium,or of bromine for iodine, produces about equal effects. Largereffects are observed when indium or thallium is substituted foriron, the changes being roughly proportional to the alteration inthe atomic weights.As regards molecular volumes and topic axes,the alkalis form the series K, NH,, Rb, Cs, ammonium and rubidiumbeing close together. Substitution affects chiefly the x and 3/values. Substitution in the iron, indium, thallium group has littleinfluence, but indium is more closely related to thallium than toiron.Atti R. Accad. Sci. Torzno, 1911, 46, 682 ; A., ii, 903.3i Zeitsch. Kryst. Min., 1911, 49, 417 ; A., ii, 890. ;jS llbid., 513246 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.It is impossible to do justice to the very comprehensive workof Ries in the short space at our disposal. Suffice it to say that i tconsists of a discussion of the chlorcl and bromo-platinates andstannates of a very large number of substituted ammonias, severalof which have been especially prepared for the purposes of thisinvestigation.The relations exhibited by these substances are verycomplex, for, although the crystals a t first sight apparently exhibitonly simple forms of the cubic system, i t is found on furtherinvestigation that a number of polymorphow forms exist whichare often either pseudo-cubic or belong to different sub-classes ofthe cubic system.The researches of Tutton have shown that in the series comprisingthe sulphates 'and selenates of the alkali metals and the doublesulphates and selenates of the type M2/SO4,Ml/SO4,6H2O, thecrystallographic properties of the rubidium salts are intermediatebetween those of the potassium and caesium compounds, and thatthose containing ammonium find a place between the rubidium andcsesium salts.F. M. Jaegers6 maintains that this regularity is notuniversal and does not hold in other groups, the morphotropicrelations of the alkali metals being in reality very complicated.As an illustration of this he quotes the salts of trichloroacetic acidof the type CC13-Cf102K,CC13*C02H, which form an isopolymorphous,in all probability isotetramorphous, series with three monoclinic andone trapezohedral tetragonal modifications. The potassium andammonium salts are tetragonal, the rubidium salt exhibits one ofthe monoclinic forms, the czsium compound the two others, thecommoner of the two being pronouncedly pseudo-tetragonal. Thethallium salt is tetragonal.Among minor investigations we may notice the following.H.Baumhauer 37 has continued his examination of the optical andcrystallographic character of the platinum double cyanides, and hasalso studied the picrates of potassium and ammonium. L. Wagner 39has measured the formates of calcium and strontium; the formersalt is rhombic &pyramidal, the labter irhombic bisphenoidal.Attempts to make mixed crystals gave results which led him toconclude that these salts are isotrimorphous. The double chromatesof magnesium with msium and rubidium have been prepared byT. V. BarkerFO who finds that they are isomorphous with the corre-sponding sulphates, and the polymorphism of the phthalylhydrazides,prepared by F. D. Chattaway and D. F. S.Wiinsch, has beenstudied by the =me author.4036 Proc. K. Akad. Wetcnsch. Amsterdam, 1911, 14, 356.87 .Zeitsch. Kryst. Min., 1911, 49, 113 ; A., i, 431.89 Trans., 1911, 99, 1326.38 Ibid., 50, 47.'O Ibid., 2263MUVERALOGICAL CHEMISTRY. 247The crystals of some fluorides, silicides, carbides, and borides,prepared by Moissan and his pupils, have been measured by A. deSchulten.41Artificial Formation of Minerals.A number of minerals have been obtained in minute crystals byheating silica, alumina, lime, potash, or soda with water in a steeltube for twelve to sixteen hours a t 350° or 450°.42 The products,which were identified microscopically, include quartz, orthoclase,albite, oligoclase, analcite, stilbite, andalusite, pyrophyllite, andmuscovite, the occurrence of the three latter being especially worthyof note.Isomorphous mixtures of the carbonates of calcium, mag-nesium, and iron have been prepared by mixing solutions of calciumchloride, magnesium chloride, magnesium sulphate, ammoniumsesquicarbonate, a.nd ferrous ammonium sulphate.43 Gelatinous precipitatm are formed, which after a time crystallise. From analysesof the products, it would seem that under these conditions iron andcalcium mix in all proportions, but that only small quantities ofmagnesium are taken up. This is in harmony with the observationthat when a magnesium-calcium carbonate is placed in ferroussulphate, the magnesium is replaced by iron more quickly than thecalcium.Artificial crystals of barytes of some size have been obtained bycrystallisation from fused barium chloride and sodium sulphate.44A somewhat similar process has resulted in the preparation of anumber of artificial apatites, a tribasic arsenate or phosphate beingfused with the chlorides of calcium, strontium, barium, or cadmium,or with cadmium bromide.On measuring the hexagonal crystals,it was found that the value of c diminishes when either themetal or the halogen is replaced by another of higher atomicweight, and that a similar change takes place when arsenic is sub-stituted for phosphorus.46The chlorine analogue of spodiosite, C%(PO&,CaF,, can also beobtained in a similar ~ a y , ~ 6 but apparently requires a lower tem-perature for its production, as on heating to redness, apatite wasobtained.This observation explains the rare occurrence ofspodimite in nature.‘I Compt. rend., 1911, 152, 1107, 1261 ; A., ii, 486, 605.42 E. Bauer and F. Becke, Zeitsch. anorg. Chem., 1911, 72, 119 ; A., ii, 991.43 W. Diesel, Zeitsch. Kryst. Min., 1911, 49, 250 ; A., ii, 725.44 H. C. Cooper, T. S. Fuller, and A. A. Klein, J. Amer. Chem. Soc., 1911, 33,45 A. de Schulten, Compt. rend., 1911, 152, 1404; A., ii, 615.UI F. K. Cameron and W. J. McCaughey, J. Physical Chenz., 1911, 15, 463;845 ; A., ii, 726.A., ii, 734248 ANNUAL REPORTS OK THE PROGRESS OF CHEMISTRY.The formation in nature of smithsonite, ZnCO,, has been imitatedby G . P i ~ l t i . ~ ~ He suspenc‘ed a rhombohedron of calcite in asolution of zinc sulphate, and after the lapse of seventeen and a-halfyears found it coated with mamillary zinc carbonate and withcrystals of gypsum.A solution of potassium nitrate left in contactwith zinc blende was found to contain sulphate,and fragments ofgalena similarly treated were found to be coated with crystals ofanglesite, PbSO,, nitrite being detected in the solution.iVew Minerals.3 chZusite.-This substance is an alteration product of t0pa.z fromthe Shepherd and Murphy Mine, Tasmania, where i t occursassociated with fluorite, cassiterite, wolframite, and topaz.48 Inappearance it resembles steatik.Baba6udam’te.-This somewhat uncouth name has been proposedfor a soda-amphibole, allied to riebeckite, which occurs in black,radiating, prismatic aggregates associated with cummingtonite inthe quartz-magnetite-schist of the Bababudan Hills, Mysore.49 Thecleavage angle is 56*, and the extinction angle somewhat greaterthan that of riebeckite, from which it differs also in pleochroism.Analysis leads to the formula 2NaFe”~(Si0,),,Fe~~Mg3(Si03),.BatcheZorite.-This has been described as a new species in arecently published list of the minerals of Ta~rnania.5~ It is ahydrated silicate of aluminium, apple-green to greenish-grey incolour, and occurs massive at the Mt.Lye11 Mine, Tasmania. Thecompmition is as follows:SiO,. A1,0,. H,O . Total. Sp. gr.49 ’4 45 ’1 5-6 100.1 3 -3Beawerite.-This mineral occurs as very minute, hexagonal plates,forming a canary-yellow, earthy-looking mass a t the Horn SilverMine, near Frisco, Beaver Co., Utah, where it is found with othersecondary minerals in the upper part of the deposit.51 On analysis,its composition was found to agree well with the formula4Cu0,4Pb0,3Fe,03,A1,0,,8S0,,16H,0, which redeces toCL~O,P~O,F~,O,,~SO,,~H~O,if the aluminium is regarded as replacing a portion of the iron.Eichb erg&.-A single specimen of an iron-grey, massive mineralhas been found embedded in magnesite at Eichberg, on the47 Atti R.Accad. Sci. Torino, 1911, 46, 783 ; A . , ii, 902.48 W. F. Petterd, Proc. Roy. SOC. Tasmania for 1910, 191.49 W. F. Smeeth, Records Mysure Ceol. Dept., 9, 85-94; A., ii, 737.60 R. F. Petterd, Proe. Roy. Soe. Tmmania f o r 1910, 22.5l B. S. Butler and W. T. Schaller, Amer. J. Sci., 1911, [iv], 32, 418MINERALOGICAL CHEMISTRY.249Semmering Pass.52gram of selected material, agree with the formula:The results of an analysis, made on half a(Cu,Fe),S,3(Bi,Sb),S3The specific gravity is 5-36,Ep'nat?-olite.-As the result of a study of the natrolite from aquarry in the neighbourhood of Schomitz, near Carlsbad, Thugutt 53has come to the conclusion that two metameric varieties of thismineral exist. In both the crystal form, the optical properties,and the chemical composition are the same, but, on heating, oneis more stable than the other. This is shown by igniting the finelypowdered mineral for a few seconds, and then adding solutions ofmethylene-blue or of silver nitrate followed by potassium chromate.The colour effects produced get weaker the longer the heating wascontinued.The less stable variety, for which the name epinatroliteis proposed, is common in phonolites, and is believed to be a decom-position product of a member of the sodalite group. The morestable variety is believed to be derived from nepheline.Fermo&e.-This interesting mineral occurs m veins of palepinkish-white or white material in the manganese ore of Sitapar,Central Provinces, India.54 The optical characters and the presenceon one specimen of a prism of 60° indicate hexagonal symmetry, aconclusion supported by the chemical composition, which conformsto the apatite type, agd may be represented by the formula3[(Ca,Sr)3(P,As),0,],Ca(OH,F),. The mineral has been namedafter L. L. Fermor, to whose elaborate investigations of the Indianmanganese deposits we owe our knowledge of juddite, sitaparite,hollandite, etc.Ferriferous Garb orundum,.-A metallic-looking substance, D 6-7,from the pulsator residues a t the Du Toits Pan Diamond Mine,Kirnberle~,~5 was found on analysis to agree approximately with theformula Fe,,Si7C7.It has not been found in situ, and is probablynot an original constituent of the " blue ground," but an artificialproduct.Ferritungstite is an alteration product of wolframite, found atthe Germania tungsten mine in the Deer Trail mining district ofWashington.66 In appearance i t is a pale yellow or brownish-yellowochre, which, under the microscope, is seen t o consist of minute,hexagonal plates. The analytical results lead to the formulaFe,O,,W 03, 6H20.5'2 0.Grosspietsch, Centr. Min., 1911, 433 ; A . , ii, 807.53 St. J. Thugutt, ibid., 405 ; A., ii, 736.54 G. F. Herbert Smith and G . T. Prior, Min. May., 1911, 16, 84 ; A . , ii, 1103.55 J. K. Sutton, Natwre, 1911, 87, 314.56 W. T. Schallcr, Amer. J. Sci., 1911, [iv], 32, 161 ; A . , ii, 903250 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Ga>te.--This mineral closely resembles magnesite in appearance,is apparently homogeneous, and, t o judge from its cleavage andoptical characters, belongs to the group of rhombohedral carbonates.57It occurs in limestone near Plr'ice, district of Gorski kotar, inCroatia. It dissolves readily in acids, and has the composition:CaO. MgO. co,. H,O. Total. Sp. gr.37'08 23.85 32.34 6.67 99'94 2.619Hexahydrite.-A course coiumnar or fibrous mineral occurs inseams or patches in an altered schistose rock in the district ofLilloet, British Columbia.It is readily soluble in water, and onanalysis was found to have a composition agreeing very closely withthe formula MgS0,,6H,0.68 The specific gravity (1.757) is some-what greater than that (1.734) recorded for the monoclinic crystalsof the artificial salt of the same composition.HinsdaZkte.-An interesting mineral, found at the Golden Fleecemine, near Lake City, Hinsdale Co., Colorad0.6~ It has the com-position 2Pb0,3A1,0,,2S03,P20,,6H20, and is therefore closelyrelated to svanbergite, the corresponding strontium compound,which appears to occur with it in isomorphous mixture, and tocorkite, in which ferric oxide plays the part of alumina.Likethese minerals, it belongs to the rhombohedral system, the crystalsbeing rhombohedra approaching cubes in shape, m'= 91°18', andhaving a basal cleavage. Viewed in polarised light, the crystals areseen to exhibit anomalies, a positive uniaxial centre being sur-rounded by biaxial sectors. The refractive indices are a = 1.670,B = 1.671, y = 1.689.LubZimite.-A name given to a variety of calcite found in felt-like masses in crevices in chalk-marl at Wysokie, Govt. Lublin,Russian Poland.boiKoZengraafite.-Small, yellowish-brown prisms, probably of mono-clinic symmetry, occur as a constituent of lujaurite, a rock of thenepheline-syenita group, in the Pilaadsberg, Transvaal.61 Theyexhibit a perfect cleavage parallel t o the orthopinacoid, and therefraction and birefringence are high (a = 1-735, y = 1.770).Theircomposition, as determined by Pisani, is as follows:SiO,. T10,. A1,0,. Fe,O, FcO. MnO. CaO. MgO. N+O. K,O. H,O. Total.28-90 27.70 3'75 0.95 2.07 2.72 19'00 2-38 10.30 0-60 1-00 99-37S q . gr. = 3'65.57 Fr. Tuhn, Centr. Mi%., 1911, 312 : A., ii, 498.58 A. A. Johnston, Summary Report Geol. Survey Branch Dcp. of Mines, Canada,59 E. S. Larsen, jun., and W. T. Schaller, Amer. J. Xci., 1911, [iv], 32, 251 ;6o J. Morozewicz, Zeitsch. Kryst. Mi%., 1910, 48, 622; A . , ii, 121.1911,256.A., ii, 1102.H, A. Brouwer, Centr. Min., 1911, 129 ; A,, ii, 296MINERALOGICAL CHEMISTRY. 251Morgn~tite.-This name has been suggested for the rose-pinkberyl from California, which is suitable for use as a gem.62 It is,however, hard to discover what useful scientific purpose is served byassociating the name of an American millionaire with a particularoccurrence of a well-known mineral.Muthmanmite.-The tellurides of gold and silver grouped togetherunder the name krennerite differ somewhat widely in composition,and Zamboniniw proposes to establish a separate species under thename muthmunnite for those of the type (Ag,Au)Te, containingabout 20 per cent.of silver, retaining the name krennerite for thoseof the type [Au(Ag)]Te,. of which the silver content is small. Aspecimen of the former mineral from Nagyag consisted of imperfectcrystals elongated in one direction, parallel t o which there was agood cleavage.The crystals were pale brass-yellow in colour, andwere found on analysis to contain 26.36 per cent. of silver, and tohave the formula (Ag,Au)Te.64Natram6 lygonjte.-The mineral occurs massive in pegmatite nearCanon City, Colorado.65 It resembles amblygonite in appearance,but contains much sodium (Na,O=11.23 per cent.), and but littlelithium (Li,O = 3-21 per cent.).(Na,Li)Al(OH,F)PO,,analogous to that of amblygonite.Neocolemanit e.-A mineral forming a considerable deposit, inter-bedded with black, carbonaceous shales, near Lang, Los Angeles Co.,California, has been termed neocolemanite on account of slightdivergences in its optical and crystallographic properties fromthose of colemanite, with which it otherwise appears t o beidentical.66 It would seem, however, that these divergences vanishif a slightly different orientation be given to the crystals, the faces001, 010, and 100 of neocolemanite being taken as 001, 010, and201 of colemanite.Poechite.-A manganese ore of the composition H,6Fe,Mn,Si30,9occurs at Vares, in Bosnia.I n colour it is red to chesnubbrown,and is believed to represent a new species.678tewartite.-A name proposed for a variety of bod, apparentlycontaining metallic iron, from the Kimberley diamond mine8.mStitchtite.-Occurs in irregular masses and veins of a rose-pink82 G. Kunz, Amer. J. Sci., 1911, [iv], 31, 81.The formula is-F. Zambonini, Zeitsch. Kryst. Min., 1911, 49, 246; A., ii, 734.C.Gastaldi, Rend. Accad. Sci. Fis. Mat. Napoli, 1911, [iiia], 17, 24 ; A., ii,W. T. Schaller, Amcr. J. Sci., 1911, [iv], 31, 48 : A., ii, 121.901.t3a A. 5. Eakle, Bull. Dcp. GcoL Univ. Catvorniffi, 1911, 6, 179; A., ii, 901.~7 F. Katzer, Chent. Zentr., 1911, i, 1660.68 J. R. Sntton, Nature, 1911, 87, 660252 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.to deep purple colour in serpentine at Dundas, Tasmania. Underthe microscope it appears to consist of strongly birefringent fibresand tufts sometimes radially disposed about nuclei of chromite.The composition is as follows:Cr,OB. Fe,O,. MgO. CO,. H,O. Total. Sp. gr.11.5 9.0 36.0 7-2 36‘1 99.8 2.12The mineral dissolves with effervescence in hydrochloric acid,affording an intensely bright green solution.It was formerlymistaken for kammererite, a member of the chlorite group.69!Z’ltortveitite.-This remarkable mineral was found in pegmatitein Iveland, south Nor way, associated with euxenite, monazite, andberyl. It forms rosettes of radial structure, some of the individualsreaching considerable dimensions. The system is orthorhombic,a: b : c=0*7456: 1 : 1.4912. The forms present are 111, 211, and110, the latter being a plane of cleavage and twinning. Thecrystals are greyish-green in colour, and translucent to transparent.The plane of the optic axes is 010, the acute negative bisectrixbeing perpendicular to 001. The mineral exhibits strong refraction(a = 1.7625 greer,) and birefringence. Its specific gravity is 3.57.Preliminary analyses have led to the interesting conclusion that thecomposition of the mineral is RJ//0,,2SiO2, where R/’/ stands forscandium and metals of the yttrium group, the former largelypreponderating. A direct determination of the scandium gaveSc,O,=37 per cent.The mineral is therefore a scandium ~ilicate.7~“aterite.-This name has been suggested for an unstable varietyof calcium carbonate, which usually occurs as spherulites, althoughsometimes in optically biaxial needles. It is distinguished fromaragonite by its lower specific gravity (2.6 about) and weakbiref r i n g e n ~ e . ~ ~PttrofZzcorite.-The mineral occurs in pegmatite in northNorway.72 It is isotropic, and possesses imperfect octahedralcleavage. The physical characters and composition vary slightly indifferent specimens.One sample of density 3-557 and refractiveindex 1-4572 (sodium light) gave, on analysis, results agreeing withthe formula 20CaF2,3YF,.I n addition to the above, investigations have been published ofa few other substances, some of which may prove to be new minerals.Among them we may notice a titano-tantalate of rare earth metals,from the State of Espirito Santo, Brmil,73 a,nd two hydrated69 W. F. Petterd, Proc. Roy. SOC. Tasmania for 1910, 167.7u J. Schetelig, Cemtr. Min., 19i1, 721 ; A., 1912, ii, 56.7l Tide C. Doelter’s Bandbatch der Mineralchemie, I , 113.72 T. Vogt, Centr. Min. , 1911, 373 ; A., ii, 733.yy J. M. de Padua e Castro, Revista Chim., 1910, 6, 365 ; A., ii, 735MINERALOGICAL CHEMISTRY.253silicates of aluminium allied to allophane from the neighbourhoodof Aywaille, Belgium.74 The first of these latter may be representedas A1,O3,Si0,,7$R20, and is easily attacked by acids; the secondhas the formula 4A1,0,,5Si0,,15H20, and resists the action of acids.Mineral Analyses.-4 egirit e.--Good, blackish-green crystals approximating closely tothe theoretical composition N+Fe,Si,O,, occur in pegmatite in theQuincy granite, Mass., U.S.A.76 The axial ratios are a : b : c=1.1044 : 1 : 0.6043 ; p = 73O27’. The crystals are pleochroic, and theextinction angle is 6O.A1lophane.-The nature of the hydrated aluminium silicates,aJloplzane, halioysit e, and montmorillonite, has often been discussed ;and while, on the one hand, the individuality of these species hasbeen maintained, it has been held, on the other, that theyare merely loose combinations or mixtures of colloidal silicic acidwith colloidal alumina.St. J. Thugutt76 finds support for theformer view in the behaviour of these substances towards organicdyestuffs, but his conclusions have been traversed by H. Stremme.77Alunite Group.-A useful discussion of this group has lately beengiven by W. T. Schaller.78 The numerous minerals composing thegroup are all rhombohedral, and may be represented by the generalformula [R’//(OH),],R/I[M],[MJ. They may be conveniently dividedinto three sub-groups, of which alunite, hamlinite, and beudantitemay be taken as types. It is suggested that goyazite is identicalwith hamlinite ; and apatelite, raimondite, pastreite, cyprusite, andutahite are all united with carphosiderite, t o which the formulaH,0,3Fe,0,,4S0,,6H20 is assigned.An analysis of alunite, found in liparite, has been publishedby U.Panichi.79A tacam’te.-H. Ungemach 80 has made an elaborate crystallo-graphic examination of this mineral, and has observed a numberof new forms. He adopts the orientation given by Phillips and byLQvy, and finds a: b : c=0*87808 : 1 : 1.32710. He regards thepratacamite of G. F. Herbert Smith as a complex twin of ordinaryatacamite. Analyses of material from Antofagasta and from Boleogave results agreeing closely with one another and with the formulaCuCl2,3Cu(OH),.74 G . Moresske, Bzd1. Xoc. gboob. Belgique, 1911, 37, 2 i 0 .75 C.Palnche and 0. H. Warren, Amer. J. S’ci., 1911, [iv], 31, 533 ; A . , ii, 614.76 C‘entr. Min., 1911, 97, 276; A . , ii, 210, 501.77 Ibid., 205; A., ii, 406.78 Amer. J. Sci., 1911, [iv], 32, 359; A., ii, 1101.79 Atti R. Accad. Lincei, 1910, [v], 19, ii, 656 ; A . , ii, 210.8o BuW. SOC. franq. Min., 1911, 35, 148 ; A,, ii, 1100254 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Bauxite.-An account of the occurrence and employment incommerce of this mineral has been given by A. Gautier.sl Thevariations in its composition are illustrated by analyses.Bertmndite.--The chemical formula, H,Be,Si20,, of this raremineral has been confirmed by the analysis of good material fromIveland, South Norway.82 The crystallographic and optical charac-ters were hlso determined.The optic axial plane is parallel to 010,and the obtuse bisectrix perpendicular to the base. 2V=74O41',and a= 1.5914, P= 1.6053, y = 1.6145 (all for Na light). Sp. gr. =2.597.Beryl.-Much attention has been paid of late to the beautifulberyls which occur in the pegmatites of Madagascar, and it wouldappear that two types can be recognised.83 One, ordinary aqua-marine, of prismatic habit and exhibiting but few faces; the otherof tabular habit, and rich in faces. Crystals of the second typecontain considerable quantities of alkali metals, particularly ofmsium, and are denser than those of the first type, and havehigher indices of refraction. Lacroix,84 however, has pointed outthat so far as composition is concerned, the analyses hitherto pub-lished indicate the existence of a continuous series of compoundswith corresponding gradations in density and refractivity.Bismath Ochre.-Amorphous bismuth ochres occur at Pala, SanDiego Co., California. A grey sample was found to consist mainlyof bismuth hydroxide.A yellow specimen had the composition ofpucherite, BiVO,, whilst another yellow specimen proved to be amixture of vanadate and hydroxide. These results tend to confirmthe view that natural bismite is a hydroxide.85Bismutoslvhnemte.-Analysea of this rare mineral published byS. D. Kusnetzoff 86 agree fairly well with the formula Bi,CO,.BZende.-The well-known transparent yellow blende fr6m Picosde Europa was found, on spectroscopic examination, to containindium, gallium, and germanium.Iron was present in --ery varyingproportions in all the specimens examined; one which was nearlycolourless contained 0.066 per cent. of ferrous sulphide only.Water extracts traces of the chlorides of calcium, potassium, sodium,and lithium from the fineiy powdered mineral.8781 Rev. g h . C'Iuirn. pure appl., 1910, 13, 389; A., ii, 497.82 T. Vogt, Zeilsch. Kryst. Min., 1911, 50, 6.L. Duparc, M. Wunder, and R. Sabot, Bull. Soc. franq. Min., 1911, 34, 131,A. Lscroix and E. Rengade, ibid., I23 ; A . , ii, 736. See also A m . Report239 ; A., ii, 1105.for 1910.85 W. T. Schaller, J. Amer. Chem. Soc., 1911, 33, 162; A., ii, 293.u7 R. Llord y Gamboa, Anal. Fis. Quim, 1910, 8, 413 ; A . , ii, 733.Bull. h a d . Sci. St. P&ersSou?+g, 1911, 8%' ; A., ii, 1104MINERALOGICAL CHEMISTRY.255Blomstrandine.-Black crystals in pegmatite from Miask, sup-posed ta be aeschynite, have proved, on analysis, to be identicalwith Brogger’s blomstrandine, a titanol-columbate of yttriumearths.88BZomstrundite.-A massive mineral of greenish-brown colour,found in pegmatite a t Ambolotara, Madagascar, was found onanalysis to be a uranif erous columbo-titanate similar in compositionto the substance from Nohl, Sweden, described by Lindstrom underthe name blomstrandite in 1874.69 It must not be confused withblomstrandine.CaEaverite.-It is interesting to notice that a study of the freezing-point curve of the system gold-tellurium has shown the presenceof a maximum corresponding with the compound AuTe2, melting a t464O.There are also two eutectic points at 4 1 6 O and 447O respec-tively, corresponding witlh 12 and 47 atomic percentages of gold.There is no indication of the formation of solid solutions.90.Cancrird e.-A reexamination of the material from Brevig,Norway, analysed by Lemberg in 1887 showed it to be quite freshand pure except for a trace of ferric oxide, t o which it owes itsred colour. Theformula deduced from the analysis of this materialis Hl,Ca,Na24A1,2Si,4C60119. Other specimens examined proved tobe impure, chiefly owing to the presence of secondary natrolite.Cancrinite is analogous in constitution to nepheline and sodalite ;on alteration i t passes to an end-product consisting mainly ofnatrolite.91Clintonite Group.-An elaborate investigation of this group isdue to E.Manas~e,~2 who has analysed with great care three differentspecimens of ottrelite from three localities in the Apuan Alps(analyses 1-111 below), as well as five other varieties, includingmasonite (IV), sismondine (V), ottrelite from Ottr6 in the Ardennes(VI), ottrelite from Mont Fenouillet (VII), and Venasquite (VIII).An equally careful analysis (IX) of a variety called salmite hasbeen made by R. de Rauw.93 The specimen came from near Ottr6,where it occurs in tables of a dark greenish-yellow colour. Itscleavages are better, and its pleochroism less intense, than those ofchloritoid, and it contains almost twice as much manganese as theoriginal salmite from Vielsalm :88 0.Hauser and H. Herzfeld, Centr. Min., 1910, 756 ; A . , ii, 46.m A. Lacroix, Bull. SOC. franq. Mi%., 1910, 33, 321 ; A . , ii, 295.G. Pellini and E. Quercigh, Atti R. Accad. Lincei, 1910, [v], 19, ii, 445 ; A.,ii, 45.y1 S. J. Thugutt, Jakrb. Min., 1911, i, 25 ; A., ii, 298.92 Atti SOC. Toscana Sci. Nut. Memorie, 1910, 26, 121, and ibid., Proc. Verb.w An?&. SOC. Gkol. Belyique, 1911, 38, 209 B.1911, 20, 29256 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.1.11.111.I V.V.VI.VII.VIII.IX.SiO,. .A120:3. Fe,c),. FeO MnO.24'37 37'03 5-36 21-91 0'5226'07 37'01 3-97 24.76 tr.25'36 38'99 2'54 23'06 tr.24-56 34.57 5'93 27-20 1'1425'36 42'58 0.72 18-02 0-5342-93 29-60 0.86 15-43 3-7530'02 34TO 4-76 20.54 1-4237.87 31.12 3'25 20.48 0'6225.50 33.57 2'01 9-16 16-631-111 and V I I show traces of TiO,.CaO.MgO. H,O.0'16 4.32 7-160'12 1.90 7 030'24 3-16 7-28- 0.36 6-640'18 5-96 7-50 - 2.12 5'481.17 1-71 6.71tr. 1'44 5.800'91 4.40 6'96Total. S p gr.100 s 3 3'44100'86 3-51100-63 3-56100'40 3-54100'85 3'45100.17 3-25101'03 3-80100'55 3'4099.79 -IX contains also 0.65 P,O,.The ratios deduced from the first five analyses lead accurately tothe formula HZFeAlzSi0,. A similar result is obtained if it beassumed that the excess of silica shown in analyses VI-VIII is dueto admixed quartz, an assumption amply justified by microscopicalexamination. I n the case of salmite (IX), after deducting fromthe silica 2-12 per cent. present as quartz, the ratios are:SiO, : A1,0, : FeO : H,O = 1 : 0.8775 : 1-25 : 0.9875.This divergence from the type is possibly due to part of themanganese being present as Mn,O,.Corundum.-The colour of the oriental sapphire has been imitatedin the artificial product by adding small quantities of ferric andtitanic oxides to the alumina used.It has now been shown thatsmall quantities of titanium (0*03-0*058 per cent. of TiO,) are alsopresent in natural sapphires, and it is therefore concluded that thecolour of the gem is due to titanium present as an oxide or asa titanate of iron.94CuprodescZoieite.-A specimen from the Old Yuma mine, Arizona,contained 11.64 per cent. CuO, and agreed with the ordinaryformula R,(V04),,R( OH),, which also expresses the composition ofsmall, black crystals of descloizite from Argenti11a.~5Dolomite.-A crystalline, ferriferous dolomite of the formula3CaC0,,2~~g~Os,FeC0, has been found in the Simplon Tunnel.gGBgZestonite.-The oxychloride of mercury, Hg,Cl,O, found origin-ally a t Terlingua, Texas, also occurs in minute cubic crystals in asiliceous matrix in serpentine in San Mateo Co., California.Ananalysis made on 0.025 gram was in agreement with the acceptedf ormula.97EmpZcctl:te.-A specimen of this mineral was found to have theformula CUB~S,.~~Eu-zenitc.--Crystal fragments from the pegmatite of Satersdal,g4 A. Perneuil, Compt. r e ~ d . , 1910, 151, 1063 ; A . , ii, 4.7.y6 F. N. Guild, Zcitsch. Kryst. Min,., 1911, 49, 321 ; A . , ii, 902.96 G. Lincio, Atti R.Accad. Xci. Torino, 1911, 46, 969 ; A . , ii, 1101.y7 A. F. Rogers, Amer. J. Sci., 1911, [iv], 32, 48 ; A . , ii, 807.9s E. Priwoznik, Osterr. Zeitsch. Berg. Hutte?iu>esen, 1910, 58, 713 ; A., ii, 991.MINERALOGICAL CHEMISTRY. 257south Norway, have been carefully examined by H. L a ~ ~ g e . ~ ~ Hisresixlts tcre very similar to those obtained by Rammelsberg forp l y c r u s e from Hittero, and support Broegger’s view that euxeniteand polymase are the end-members of a series, in which the ratioMZOj :TiO, varies between the limits 1 : 2 and 1 : 6. Full detailsof the analyticai methods employed are given in this paper, togetherwith a discussion of the method of separating tantalic, niobic, andtitanic acids by means of ammonium salicylate.A specimen ofthe same mineral from Ambolotara, Madagascar, had a compositionclosely resembling that of the material from Arendal and fromEydland.1Fa;yulite.-A complete crystallographic and optical examinationof the small, orthorhombic crystals from the Cuddia Mida craterin the island of Pantelleria, has been made by J. Soellner.2 Thecomposition may be expressed by the formula Mg2Si0,,10Fe2Si0,,portions of the magnesium, iron, and silicon being replaced bycalcium, manganese, and titanium respectively. The relationsbetween the optical constants and the percentage of ferrous ironare in harmony with the results of Yenfield and Forbes.3 The axialratios and refractive indices are as follows:a = 1.8044, fi = 1.8383, y = 1.8462 ; 2V = 51° (yellow Hg light).Theoptic axial plane is 001. The acute negative bisectrix is perpendi-cular to 010.Pelspar. Group.-Analyses of two potash-felspars and of eightplagioclases ranging from Ab,.,An to Ab,.lAn have been given byI. Nordenskjold4 in the course of a general account of the mineralsfound in the pegmatite of Ytterby, Sweden. A labradorite of thecomposition Ab,An,.,,, from Yinacate, Sonora, Mexico, has beenexamined by Y. S. Bonilla~,~ and may be compared with themineral described by Ford and Bradley from the Altai Mountains.6A microperthite from the Ilmen Mountains and an oligoclase-albitefrom the south Urals have been described by W. W. Arschinow.7The former can be obtained in transparent pieces, which lend them-selves to optical examination; i t contains barium, and may be repre-sented by the formula Or,9Ab4,,Ce,. The latter is approximately(L : 5 : c = 0.4600 : 1 : 0.5811 ;Ab80An20.Zeitsch. Nuturwiss.FTalZe, 1910, 82, 1 ; A . , ii, 499.A. Lacroix, Bull. Soc. franq. Min., 1910, 33, 321 ; A., ii, 295.Zeitsch. Kryst. Nin., 1911, 49, 138 ; A . , ii, 502.A . , 1896, ii, 373.BUZZ. Geol. Imt. Unia. Upsalu, 1910, 9, 183; A., ii, 296.Parergones Inst. Geol. Mexico, 1910, 3, 427.Ann. Zeport, 1910, 244.Piiblication of the Petrographical Institute, Lithopca, Moscow, 191 I, 12 pp.REP.-VOL. VIII 258 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.As the result of an examination of a large number of felspars,Barbier found that orthoclases always contain small quantities oflithium and sometimes of rubidium, but that these elements do notoccur in microcline.8 These conclusions have been contested byW.I. Vernadsky and Mlle. E. Revutsky,Q but in a criticism of theirwork Barbier maintains his position,lO and still regards the presenceor absence of lithium as constituting a fundamental differencebetween the species.Garnet Group.-Analyses have been published of ipecimens ofandradite from Assynt., Sutherlandshire,ll from Sardinia,lZ and fromBerks County, Pennsylvania.l3 The first is a dark brown melaniteof rhombic dodecahedra1 habit, and contains 6-74 per cent. ofTiO,; the second is a honey-yellow garnet, and agrees very closelywith the formula Ca,Fe,(SiO,),, part of the iron being replaced byaluminium; the third is very similar to the second.Glazc6erite.-Brick-red nodules from Varang&lle, near Nancy,have a composition agreeing with the usual formula,Na,S0,,CaS04.14GZmcodote.-If hea-ted in a vacuum this mineral loses a littlesulphur and arsenic; if roasted and again heated, more sulphurand arsenic are obtained, until finally 4.38 per cent.of the sulphurand 23-37 per cent. of the arsenic contained in the mineral arefound in the distillate.15 The effect of roasting is apparently toproduce some disulphide, which on heating decomposes into mono-sulphide and sulphur. These experiments support the view thatglaucodote has the formulaSOASS*AsFe< I >co.Goldschinidtit e.-The individuality of this mineral has beendisputed by Palache, who on crysta.llographic grounds regarded itas identical with sylvanite.It appears, however, that its compositionis approximately represented by the formula (Au,Ag)zTe5, and i tmay therefore be properly regarded as a separate species.16Herderite.-A crystallographic examination of the material fromMt. Apatite, Auburn, Maine, has shown that the substance crystal-Ann. Mcport, 1909, 211.Compt. rcnd., 1910, 152, 1372 ; A . , ii, 122.lo BUZZ SOC. fmnq. Min., 1911, 34, 117 ; A., ii, 735.l1 A. Gemmell, Tmns. Edijtburyh Ggol. SOC., 1910, 9, 417 ; A!., ii, 300.l2 A. Serra, B m d . Accnd. Sci. Fis. Mut. Napoh, 1910, [iii], 16, 222; A . , ii, 123.E. F. Smith, Proc. Acnd. S a t . Sci. PhiZndeZphicc, 1911, 62, 538 : A . , ii, 501.V. Dlirrfeld, Mitt. geol. Lundesanstalt E2sass-Lolluingen, 1911, 7, 345 ; A., ii,295.'' A. Bcntell, Centr. Min., 1911, 411 ; A . , ii, 728.16: c. Gastsldi, Bend. Accnd. Sci. Pis. Meet. Nnpoli, 1911, @a], 17, 22 ; kf., ii, 901MINERALOGICAL CHEMISTRY. 259lises in the monoclinic system, two crystals being commonly twinnedtogether to form a, pseudorhoinbic individual. A partial analysisproved that the substance was a hydrofluorherderite,but as the angles approach nearer to those given by Penfield forhydroherderite than to those given by Dana for the hydrofluor-herderite from Stoneham, it is considered probable that Penfield'sangles hold for all varieties of the mineral.17HowZite.-Nodular masses of this remarkable calcium silico-borateoccur a t Lang, Los Angeles Co., California.18 The composition maybe represented by the formula C?~B,0,,B(OH),,H2Si0,.~yPersthen,e.-Specimens found in andesite rocks on the bordersof Transylvania aiid Bukovina have been studied by V.C. Butu-reanu.19 The crystals, which have the ratiosa : b : c=0.97 : 1 :0*57,are often twinned.on black, green, and greenish-grey crystals rmpectively :CaI[G(F,OH)]PO,,The three following analyses 1-111 were madeSiO, A1,0,. Fe(Mn)O. CaO. MgO. H,O. Total.I. 49'43 3'10 14'75 4'17 27.00 1.66 100'1111. 49 80 1.40 12.00 10.25 26.00 0.84 100 39111. 50'15 2.02 10.24 8.00 28.85 0.95 10021Jamesonite.-W. T. Schaller 20 is of opinion that the best analysesof this mineral are more in harmony with the formula4PbS,FeS,3Sb2S3,proposed by Loczka, than with the more complicated formula,7( Pb$, Fe+)S,4Sb2S3, adopted by Spencer.The mineral warrenite,held by Spencer t o be identical with jamesonite, is shown to be amixture of jumesonite and zinkemite, PbS,Sb,S,.EuoZinite.-In the course of a study of the heating curve of thismineral, Mellor and Holdcroft 21 have shown that an endothermicreaction occurs about 500O. This may be interpreted as indicatingthe decomposition of the kaolinite into silica, alumina, and water.A t 800° an exothermic reaction takes place, due to a change in thephysical condition of the alumina. They regard kaolinite as analuminodisilicic acid, (Ho)2>A12<E:EiZ>0, and point out thatother silicates may be referred to similar acids. The composition( W 2of a specimen from Northumberland,22 occurring in silvery-white17 TY.E. Ford, Amer. J. Sci., 1911, [iv], 32, 283 ; A . , ii, 1102.18 A. S. Eakle, Bull. Dept. Geol. Univ. California, 1911, 6, 179 ; A . , ii, 901.l9 AWL. Sci. Univ. Ja~sy, 1910, 6, 287.21 J. W. Rlellor and A. D. Holdcroft, Trans. Eng. Ceramic SOC., 1911, 10, 94 ;22 It. C. Burton, Proc. Univ. Durham Phil. Soc.. 1911, 4, 24 ; A . , ii, 735.Zeitsch. Kryst. 'Win., 1911, 48, 562 ; A . , ii, 209.A . , ii, 607.s 260 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.scales, showing a basal cleavage and a biaxial interference figure,agreed very closely with the formula A1,0,,2Si0,,2II2O.Marcasite.-The question as to the state of oxidation of the ironin this mineral has often been discussed. Recent experiments, inwhich the substance has been heated in a sealed tube a t 250° withcarbon tetrachloride or fused with bismuth chloride in an atmo-sphere of carbon dioxide, indicate that the iron is all present in theferrous state.23MispickeZ.-An attempt has been made to elucidate the constitu-tion of this mineral by studying its behaviour when heated in avacuum (compare glaucodote, p.258 above). In these circumstancessmall quantities of sulphur and of arsenic sulphide distil over,together with arsenic amounting to 12.2 per cent. of the substancetaken. The whole of the arsenic is not expelled, even if the heatingbe continued for a long time, but both the arsenic and sulphurcan readily be driven off if the substance is first roasted andthen distilled in a vacuum.The conclusion is drawn that theformula is Fe2As2S2, and the constitution analogous to that ofglaucodot e.24NepheZine.-In the case of natural minerals i t is often impossibleto deduce satisfactory formulce from the results of analysw carriedout with all care on apparently pure and homogeneous material.The suggestion has therefore been made that in such cases we aredealing with homogeneous mixtures of different compounds, someother constituent being preselnt in solid solution in the mineral.25This theory has been applied to explain the divergence of nephelinefrom the simple formula NaAlSiO,. Carefully selected materialfrom Eikaholmen, Norway, gave the ratios :SiO, : Al,O, : Na20 = 2.23 : 1.00 : 0.98.The analyses published by Morozewicz yielded similar results, theratio Si0,:A120, varying from 2-11 to 2.21.It is therefore con-cluded that the excess of silica is present in solid solution.Another view of the constitution of this substance has beenpropounded by W. T. Schaller,26 who regards it as a mixture of thefour isomorphous molecules, NaAlSiO,, KAlSiO,, CaA12Si20,,NaAlSi,O,, just as the plagioclase felspars are mixtures of themolecules NaAlSi,O, (albite), CaA12Si20, (anorthite), NaAlSiO,(#carnegieite), and KAlSi,O, (microcline).Olivine Group.- The data correlating optical properties andchemical composition in this group have been brought together by23 G. W. IJlummer, J. Amer. C'hem. Soc., 1911, 33, 1487; A . , ii, 901.24 A. Beutell, Centr. Min., 1911, 316 ; A., ii, 485.25 H.W. Foote and W. M. Bradley, Amer. J. Sci., 1911, [iv], 31, 25 ; A . , ii, 122.26 J. Washington Acnd. Sci., 1911, 1, 109 ; A . , ii, 992MINERALOGICAL CHEMISTRY. 261H. Backlund,27 who has also made numerous determinations ofrefractive indices and several new analyses. An abstract of thismemoir, which appeared originally in Russian, is now available forEnglish readers.0rthite.-Irregular masses of this mineral found in a felsparquarry a t Impilaks, on Lake Ladoga, were found on analysis tQcontain up to 1 per cent. of scandium oxide.28 Wiikite, anothermineral containing appreciable quantities of scandium, occurs a t thesame locality.Parisite.-A considerable addition to our knowledge of this rareflu-carbonate of cerium, lanthanum, and didymium has been madeby the study of the small, yellow crystals of rhombohedra1 habitfound in pegmatite a t Quincy, Massachusetts.29 The refractiveindices, o = 1.676 and E = 1-757, are considerably higher than thosepreviously accepted.The composition may be expressed by theformula (R/”F),Ca(C?O,),, where R”/ = Ce,La;,Di, and it is suggestedthat synchysite from Greenland is probably a variety of this mineralcontaining admixed calcite.Pearcede.-The formula S(Ag,Cu),S,As,S, was assigned to thismineral by Penfield in 1896, and it wm regarded by him as thearsenic analogue of polybasite, 9Ag2S,Sb2S,. The results of a carefulanalysis30 of black, platy crystals from the Veta Rica Mine,Coahuila, Mexico, agree, however, very closely with the formula8(Ag,Cu),,S,As,S,, and i t would appear also that the publishedanalyses of polybasite agree better with a formula of this type thanwith that which has hitherto been generally accepted.31Two analyses of the latter mineral recently made by H.Unge-mach32 on material from Las Chiapas, Sonora, and from Sonora,Mexico, respectively, are in harmony with this conclusion.Phosphorite Group.-A study of the published analyses of collo-phartite, dahllite (= podolite), and francolite (= staffelite) has ledW. T. Schaller to the conclusion that the following formulz arethe most probable 33 :Dahllitc.. ......................... 9Ca0,SP20,,Cn0, CO,, H,OFrancolite ........ %.. ............. 9Ca0, 3P20,,CaF2, CO,, H,OCollophanite ..................9Ca0,3P,05, Ca0,C02, H20 f nH20.Platinum.-The geological conditions under which this metal27 Trav. Must?e Gid. Pierre le grand Acad. Sci. St. Pilersbourg, 1909, 3, 77 ; A.,28 R. J. Meyer, Sitzunysber. K. Akad. Wiss. Bcrlin, 1911, 379 ; A . , ii, 406.29 C. Palxche and C. H. Warren, Am,er. J. Sci., 1911, [iv], 31, 533 ; A . , ii, 614.3 o F. R. van Horn and C. W. Cook, ibid., 518; A., ii, 614.31 F. R. van Horn, ibid., 32, 40 ; A., ii, 807.32 Bull. Soc. frang. Min., 1910, 33, 375; A., ii, 614.33 J. Washington Acad. Sci., 1911, 1, 151 ; A,, ii, 1102.ii, 616262 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.occurs in the Urals have been examined by L. Duparc,34 and fifteenanalyses of native platinum collected from stream beds in variouslocalities in that district have been made by H.C. Holtz.35PZum6ojarosite.-This rare mineral has been found lately in someabundance a t several localities in Beaver County, Utah.% It isdark brown in colour, and micaceous in structure. Under themicroscope the crystals are seen to be thin, uniaxial, hexagonalplates, optically negative, and strongly birefringent. Analysis gaveresults agreeing well with those previously obtained and in harmonywith the formula Pb0,3Fe20,,4S0,,6H,0.PoweZZite.-White plates analysed by S. D. Kusnetzoff 37 gaveresults agreeing closely with the formula CaMoO,. They thus differconsiderably from the Idaho specimens, in which part of themolybdenum is replaced by tungsten.Pyrites.-An elaborate study of the figures produced by etchingpolished faces of crystals of iron pyrites has been made by V.Posch1,M and he has also measured the hardness of the mineral indifferent directions.As the result of these experiments he concludesthat the crystals probably belong to the tetrahedraLpentagona1-dodecahedra1 sub-class of the cubic system. In the course of theinvestigation specimens from Elba, from Huttenberg, Carinthia,and from Seegraben in Styria were analysed. The composition ofthe specifically lightest and heaviest crystals from each locality wasdetermined, but although the density varied by as much as 0.05, noessential difference in composition could be detected. All the speci-mens contained arsenic, ranging from 0.78 to 1.73 per cent., andcopper from 0.04 to 0.63 per cent.I n order t o obtain information as to the state of oxidation ofthe iron in this mineral, G.W. Plummer has heated it to 250° withcarbon tetrachloride in a sealed tubs. Under these conditions75 per cent. of the iron is obtained in the ferrous state. He hasalso found that i t is readily decomposed by fusion with bismuthtrichloride in an atmosphere of carbon dioxide, all the iron remain-ing in the ferrous state. He therefore concludes that the whole ofthe iron is ferrous. This view is supported by the experiments ofL. Benedetk,sQ who has found that when heated to redness in anatmosphere of carbon dioxide, pyrites loses half its sulphur, ferroussulphide being left.Pyrurgyrite.4. Loczka 40 has analysed the crystals from34 Awh.Xci. phys. nut., 1911, [iv], 31, 211, 322, 439, 516 ; A., ii, 733.85 Tbid., and'also Tsch. Min. Mitt., 1910, 29, 498.3F 13. S. Butler and W. T. Schaller, Amcr. J. Sci., 1911, [iv], 32, 422.%7 Bull. Acad. Sci. St. Pt?tersbourg, 1911, 897; A . , ii, 1104.38 Zeitsch. Kyyst. Min., 1911, 48, 572 ; A., ii, 208.79 Zbid., 1910,'48, 447; A,. ii, 44. 40 Ann. Mus. H u g . , 1911, 9, 318MI N ERA LOG I C A L C H EM 1 S’I’R Y . 263NagybBnya, Hungary, which have been described by K. ZimSn~i.~lThe results are as follows:S. Ag. Cu. Fe. Sb. As. Total. Sp. gr.17.82 59-82 0.07 0’12 22-00 0.08 99’91 5.851Rieb eckite.-Long, black, prismatic crystals intergrown withaegirite occur in pegmatite in the Quincy granite of Massachusetts.42The cleavage angle is 55O5’.The optic axial plane is perpendicularto 010, and the acute negative bisectrix inclined 4-5O with thelong axis of the prism. Thecomposition of the specimen conforms t o the typebut only contains 42 per cent. of the first of these two molecules.It therefore resembles the specimens from New Hampshire andColorado rather than the original mineral from Socotra.Rhodizite.-In 1909 an analysis, by Pisani, of this rare substancefrom Madagascar was published by Lacroix.43 Two large crystalsfrom Ampakite, Madagascar, have recently been examined, and aportion of one of them has been found to have the compositionB,,Al,Gl,(Li,K,Crs,Rb,Na,H)4039, the percentages obtained differingconsiderably from those found by Pisani. The crystals are pseudo-cubic, being apparently rho;mbic dodecahedra, showing small facesof two complementary tetrahedra.44Rinmeite.-An analysis of carefully selected material fromHildesia confirms the formula FeCl2,3KCI,NaG1, given t o theoriginal mineral from Wolkramshausen.45 It can be prepared arti-ficially in rhombohedral crystals, and is to be regarded as a triplesalt, and not as an isomorphous mixture.An experimental investi-gation of the conditions under which iron salts occur in thePrussian potash-salt deposits has been carried out by H. E. Boeke,the discoverer of rinneite. He has studied the crystallisation ofsolut.ions of ferrous chloride and magnesium chloride, of ferrouschloride and potassium chloride, and of the three chlorides together,and deduced the equilibrium diagrams.46Schwartzemb erg&.-This substance has hitherto been regardedas an oxychloriodide of lead crystallising in the rhombohedralsystem. A recent investigation 47 of material from the San Rafaelmine, Sierra Gorda, Chili, has, however, shown that the crystals41 Am.Mzcs. Hung., 1911, 9, 251.42 C. Pnlache and C. H. Warren, Amer. J. Sci., 1911, [iv], 31, 533 ; A , , ii, 614.43 Ann. Report, 1909, 217.44 L. Duparc, M. Wuuder, and R. Sabot, B i d . floe. fran?. Min., 1911, 34, 132 ;The mineral is intensely pleochroic.N~Fe2Si4012,R4Si4012,A . , ii, 1105.F. Rinne and R. Kolb, Centr. Briin., 1911, 337 ; A., ii, 613.a. F. Herbert Smith and G . T. Prior, Min. Affig., 1911, 16, 77 ; A., ii, 1100.xi Jahrb. Min., 1911, i, 48 ; A., ii, 293264 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.are tetragolnal, and that the iodine is present, not as iodide, butas iodate.The analytical results are in agreement with the formula3 (P b Cl,, 2Pb 0) , P b ( 103)2,Stibiotuntdite.-In certain analyses of this mineral 48 tantalumand columbium were estimated by taking the specific gravity of themixed oxides on the assumption that this property is a linearfunction of the composition. Recent researches 49 show, however,that this is not quite the case, and a correction amounting to about2 per cent. must be applied to those analyses.Striiverite.-This interesting mineral, originally described byZambonini and Prior, from Craveggia, Piedmont, has recently beenfound in abundance in a pegmatite vein in the Black Hills of SouthDak0ta.5~ The small, black crystals resemble columbite in appear-ance, and are tetragonal, with angles near those of rutile.Themineral was completely decomposed on fusion with sodium hydrogensulphate, but owing to the difficulties attending the separation ofcolumbium, tantalum, and titanium somewhat different results wereobtained by different methods. The mean result approximates tothe formula Fe0,(Ta,Cb),0,,6Ti02. The mineral contains moretantalum than the original struverite, to which Prior gave theformula Fe0,(Ta,Cb),0,,4Ti02.Thuumasite.-This curious mineral, hitherto only recorded fromSweden and from New Jersey, has lately been observed in fissuresin metamorphosed dolomitic limestone in Beaver County, Utah.51The composition of the pure white material agrees with the acceptedformula, 3C'a0,Si02,,S0,,00,,15H20.Its specific gravity has theremarkably low value 1.84.Tikxsite.-In 1895 H. Sjiigren described a massive mineral ofthe composition (MgF)CaAs04. Pale green crystals of the sameformula have been found recently in manganese ore at Kajlidongri,Jhabua State, India, and have been subjected to a tborough exam-ination by G. F. Herbert Smith and G. T. Prior.b2 It would seemprobable that the curiously developed and often twinned crystalsbelong to that class of the monoclinic system which only exhibitssymmetry about a plane : a : b : c = 0.7503 : 1 : 0.8391 ; 0 = 5 9 O O g Theoptical characters agree with those determined by Sjogren, an acutenegative bisectrix emerging perpendicular to the good cleavage face101, the optic axial angle being large, 2V=82O44/, and the planeof the axes perpendicular to 010. The refractive indices area = 1.640, = 1.660, y = le6'i5(Na).D 3-77.-Ann. Aeport, 1906, 326.F. L. Hess and R. C. Wells, ibid., 31, 432 ; A . , ii, 499.49 W. E. Ford, Amer. J. Sci., 1911, [iv], 32, 287 ; A . , ii, 1104.51 B. S. Butler atid W. T. Schaller, ibid., 131 ; A . , ii, 209.gJ Min, ~Ifag., 1911, 16, 84 ; A., ii, 1103MlNERA LOGIC AL CHEMISTRY. 265Variscite.-W. T. Schaller53 has found that the bright green,orthorhombic crystals of this substance from Lucin, Utah, havethe usual formula, A1,0,,P20,,4H,0.Zeolite Group-A very large number of a(na1yses of members ofthis group have been published during the year.As none of themhas led to results of special novelty or importance, it will sufficehere t o refer to the work of E. F. Smith54 and F. A. Canfield.66Met eorites.Among the numerous investigations of these substances carriedout during the year, several of a general character claim attention.The first of these is the attempt made by 0. C. Farrington66 toapply to the stoney meteorites the system devised in America for theclassification of igneous rocks. With this object in view Farringtonhas made a critical compilation of the published analyses of thesemeteorites. In fitting them into the classification, certain modifica-tions of the latter become necessary, for regional names cannot beused for designating orders, sections, etc.A'ccordingly, a groupname is assigned to the sub-range only, the name chosen being thatof a meteorite which may be considered typical. Further, thepresence of uncombined metal in the meteorites necessitates theformation of several new sub-classes. Most of the meteorites falloutside the groups of terrestrial rocks, but Juvinose, Udenoae,Stawropdose, Bishopvillme, and Bustose among meteorites corre-spond respectively with Kedabdekase, Wehrlose, Argeinose, Mari-cose, and Websterose among igneous rocks. The minerals ofmeteorites are divided into two groups, salic and femic. The formerincludes quartz, leucite, felspar, and nepheline ; the latter pyroxene,olivine, magnetite, apatite, troilite, oldhamite, schreibersite, andnickel-iron.The methods of calculation employed and the mode ofinterpreting the analyses are fully set forth in Farrington'smemoir.The distribution of the elements in meteorites and the structureof these substances have been discussed by Wahl.67 He points outthat whereas many meteoric irons have been discovered long aftertheir fall, this is not the case with the stoney meteorites, whichare liable to escape detection altogether, unless their fall is actuallyobserved.If this is not kept in mind false estimates as to the relative53 J . Washington Acad. Sci., 1911, 1, 150; -4., ii, 1103.54 Proc. dcnd. Nut. Sci. Phil., 1911, 62. 538 ; A., ii, 501.55 Xchool M i n e s Quart. New York, 1911, 32, 215.57 W. A. Wahl, Zeitsch. anorg Chew&., 1910, 69, 52; A ., ii, 47.Field Museum of Natural Eistory. Publication 151, Geol. Series, 1911, 3, 195266 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.importance of iron in meteorites may easily be framed. The presenceof easily oxidisable minerals, such as nickel-iron, troilite, etc., andthe complete absence of those containing hydroxyl is especiallycharacteristic of meteorites; their magmas were in fact (( dry melts,”and may be compared with those of basic rocks. The only terrestrialirons which can be compared with meteoric irons are those fromDisco, and they contain more carbon and more oxygen than aremet with in any meteoric iron.Speaking generally, it may be said that meteorites and theircomponent minerals differ from terrestrial minerals and rocks incontaining a smaller amount of oxygen, and the meteorites them-selves may be classified according to their degree of oxidation.The presence of nickel in the metallic part of meteorites and itsabsence from the olivine is explained by the fact that the heatof formation of nickel oxide is lower than that of iron oxide.Whenall the available oxygen is exhausted, any calcium left unoxidisedunites with the sulphur present to form oldhamite, CaS. If thereis enough sulphur, iron sulphide is next formed. The sulphides ofcobalt and nickel are not met with, as their heats of formationare less than that of iron sulphide.These considerations combined with a study of the structure ofmeteorites leads to the conclusion that the meteorites are smallparts of larger bodies, and underwent various changes while stillbelonging to these larger bodies.The composition of these largerbodies was probably similar in all cases, the different varieties ofmet,eorit.es coming from different zones. The achondrites andsiderolites represent the solidified interior portions, and may becompared with the deep-seated igneous rocks. The chondrites comefrom the outer layers, and correspond to some extent with terrestrialeruptive rocks.Some experiments on the synthetical production of meteoric ironhave been made by Benedicks.68 He finds that alloys of iron with12 per cent. of nickel, prepa.red by the alumino-thermic process andcooled very slowly below 350°, have a structure which very closelyresembles that of the octahedral irons.On the other hand, Ovifakiron resembles a high-carbon steel, and contains free cementite andpearlite, a substance not found in meteoric iron.59 The atomicweight of the iron of a meteorite from Mexico has been determined,and the results found to agree exactly with those obtained by similarmethods for ordinary iron.6058 C. Benetlicks, Aletnllicrgie, 1911, 8, 85 ; A . , ii, 495.59 Ibid., 65 ; A . , ii, 287.6o G. P. Baxter and T. Thorvaldson, J. Amer. Chem. SOC., 1911, 33, 337 ; A , , ii,288MIFERALOQICAL CHEMISTRY. 267The composition of taenite has been discussed by 0. C. Farring-ton.61The question as to the origin of the curious glasses known asmoldavite, billitonite, etc., still continues to arouse much interest.On the one hand, their extra-terrestrial origin is maintained, andthey are classed together as a special group of meteorites under thename of tektites; on the other, they are regarded as obsidian orvolcanic glasses. Several contributions to our knowledge of theseobjects have been made recently. R. Beck 62 has analysed the gasesenclosed in tektites, and has compared them with those obtainedfrom obsidian. The former are distinguished by the presence ofconsiderable quantities of oxides of carbon and by the absence offree chlorine and hydrochloric acid. Certain small beads foundin prehistoric burial places in Bohemia have been found on analysisto consist of a highly basic glass.63 As an artificial origin for theseobjects seems highly improbable, and as their composition is quitedifferent to that of any known natural glass, i t is suggested thatthey probably belong to the class of tektites.One of the principal arguments relied on by the upholders ofthe meteoric theory is the peculiar character of the surface mark-ings of tektites. It would appear, however, that certain glassesfound in America exhibit very similar markings to those ofmoldavite and billit0nite.6~9 66 I n the light of these observationsthe case for the meteoric origin of the tektites becomes lessconvincing than it was.Among individual meteorites which have been examined latelywe may n d e the following :Dokhchi-In 1903 a number of meteoric stones fell in the neigh-bourhood of Dokiichi, Decca district of Bengal. The examinationof one of the smaller of these has shown it to consist of a finelygranular mixture of olivine and bronzite with irregular grains ofnickel-iron and traces of troilite. Analyses have been made of thenickel-iron and of the silicates attacked by hydrochloric acid, aswell as of the silicates undecomposed by that acid.@jEl Nakhla.-This meteorite fell recently near Alexandria, and issaid to consist largely of fragments of hypersthene.67 As severalanalysts have been a t work on it, further communications may beIt would appear to vary between Fe,Ni and FeNi.expected in the near future.Field Museum Nat. Hist. Pub. 145, Geol. Ser., 1910, 3, 165.62 Jfonntsbc?-. Dczctsch. Geol. Gs., 1910, 3, 240 ; A , , ii, 292.63 E. Weinsclienk and H. Stcinmetz, Centr. Jfin., 1911, 231 ; i l . , ijG. P. Merrill, Proc. United States Nat. M~~sczonz, 1911, 40, 481.‘jT, B. Jeiek and J. WoldEich, BtcEI. Intern. Acnd. Sci. Boh&me, 1920,H. E. Clarke and H. L. Bowmnii, Jfin. Mag., 1911, 16, 35 ; A.,S. Jleiiiier, Compt. rend., 1911, 153, 785 ; A., ii, 1106.501.15.i, 616268 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Leighton.-A stone weighing 877 grams fell in 1907 nearLeighton, in Colbert Co., Alabama. It is a grey chondrite.Quinn Canyon.-A mass of iron weighing 1450 kilos. was foundin 1908 near the Quinn Canyon Mountains, Nye Co., Nevada. Itis a medium octahedrite, and contains 7-33 per cent. of nickel.0. C. Farrington,68 who has described the two meteorites lastmentioned, has also given a complete list of all the meteorites foundin the United States.A. HUTCHINSON.Field Nus. Nat. Hist., Pub. 145, Gcol. Ser., 1910, 3, 165 ; A., ii, 407

ISSN:0365-6217    

DOI:10.1039/AR9110800238

出版商:RSC    

年代:1911

数据来源: RSC

摘要:

RADIOACTIVITY.Theories of the Elements.A STRUCTURAL theory of the atomic weights of the elements hasbeen put forward 1 which has a definite theoretical foundation, andis certainly in surprisingly good accord with the best chemicaldeterminations. The underlying idea is to regard the whole massof an atom as of purely electromagnetic origin due to the presenceof equivalent charges of positive and negative electricity. Thelatter are the well-known negative electrons, which, as is nowgenerally admitted, can only represent an insignificant fraction ofthe total mam of any atom. The unknown positive charges aretherefore regarded as existing in units excessively small in radiuscompared even with the radius of the negative electron, and sincethe inertia, or mass, is proportional to e2/a, where e is the chargeand a is the radius, the mass contributed by the positive chargesis so increased until it represents nearly the total atomic mass.In other words, the unit positive charge is regarded as an entityas much smaller than the negative electron as the latter is smallerthan the atom.Sir J. J. Thomson’s original view that the positiveelectricity has a uniform volume distribution is, however, retained,and is essential. The author then constructs four primary atomsor “protyles,” out of which all atoms are built up. The singleelectron, with its equivalent single concentrated positive charge,cannot exist, but for systems, respectively, of two, three, four, andfive negative electrons, in rings at equidistant intervals round asingle equivalent concentrated positive charge, permanence may beassumed, as in such ring systems the vector sum of the accelerationstowards the centre is zero, and the drain on the kinetic energy ofthe system due to radiation is null.Quite definitely, then, in thisconception, the positive charge is a single sphere of uniform volumedistiibution of from 2 to 5 atomic charges of positive electricity.The radius of this sphere is therefore proportional to n1/3, where nis the number of atomic charges. The inertia, or mm, which is, asalready stated, practically the whole atomic mass, being p r eJ. W. Nicholson, Phil. Mag., 1911, [vi], 22, 864; A . , 1912, ii, 35.20270 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.portional to e2/a, is proportional to n2/n1/3, that is, t o n5/3, so thatthe atomic weights of the four protyles are, neglecting, as is per-missible, the mass of the negative electrons, in the ratio of thenumbers 2, 3, 4, and 5 raised t o the 5/3rds power.The first ofthese is taken to be coronium (Cn), the second, hydrogen, the third,nebulium (Nu), and the last, protofluorine (Pf). It must bementioned that it is not definitely postulated that hydrogen is asingle three-electron ring system, but possibly may be some multipleof such a system, presumably not a large multiple, with correspond-ing changes in the structure of the other protyles. Hence theradius of the positive sphere of electrification is left indefinite.Taking the atomic weight of hydrogen as 1.008, the relative atomicweights of the others, corrected for the mass of the equivalentnegative electrons, are :Cn 0.5131 Nu 1.6277 Pf 2-3604.Only the two latter and hydrogen enter into the composition ofthe known elements, coronium being regarded, on account of itssimple structure, as less stable.It is stated that the spectra ofcoronium and protofluorine in the solar corona, and of nebulium innebulae, give mathematical justification for the structures assigned,but unfortunately this interesting point is not discussed furtherin the paper. The structure of the elements of atomic weight below25, and i t is only these in which the chances of accidental coinci-dence is small, is then represented in the second column of thefollowing table.The third column represents the atomic weightcalculated from the structure, and the last that given in theInternational List :Helium ...................Lithium ..................Glucinum ...............Boron .....................Carbon ..................Nitrogen. ................Oxygen .................Fluorine ..................Neon .....................Sodium ..................Magnesiuni.. .............3-9886-909.09711'0012 00814.0215.99619 '0220.2123'00824-323-996.949.1011 -0012.0014.0116.0019,o20.223-0024'82The structures assigned appear somewhat arbitrary, but thecoincidence between the calculated and the determined atomisweight, except in the case of lithium, is extraordinary.It iscurious to note that the approximation to whole numbers of theatomic weights nowhere enters explicitly into this scheme, butwould appear to be an accidental consequence of the values of thefive-third powers of the numerals 3, 4, and 5, and the unit chosenfor oxygen. The underlying theoretical idea is commendablRADIOACTIVITY. 27 1.definite and simple, but its further development in the paper isvery open to criticism. For example, the author is a t pains toconstruct three new inert gases having positions in the PeriodicTable between cobalt and copper, palladium and silver, platinumand gold, which surely is in violatlon of all probability. Again,the evidence that the a-particles of the radio-elements differ onlyin the initial velocity of their expulsion, which has been discussedfully in these Reports, appears to be largely unknown to the author,who regards it as " not in opposition to any phenomena known withcertainty " that the a-particles from different sources mFy consistof different atoms. Whereas in most cases separate determinationsof the velocity and of the ratio of the charge to the mass areavailable.Some of the radioactive evidence cited is well known tobe erroneous; for example, the statement that the a-rays of poloniumand radium are equally deviated in the magnetic field.2 Apparentlythere is a difficulty in obtaining satisfactory constitutions for theradio-elements which shall exhibit> them as successive transformationproducts by losses of helium atoms, whereas one of the mostinteresting features from the radioactive point of view of thestructures assigned to the lighter atoms in the table given is thepredominant part assigned t o helium.The attempt has been made3 to revive the cubic periodic system,once proposed by Mendeleeff to accommodate the rare gases, thenew rare earths, and the disintegration products of radioactiveelements.The feature of this proposal is that 120 possible placesare assigned to the elements, excluding hydrogen, which arearranged in eight families, each containing fifteen places in sub-families of five, the first member of the family being placed abovethe fourth, the second above the fifth, and so on. It is pointedout that on this system the sum of all the known atomic weightsis within 0.3 per cent.of the calculated value, oxi the assumptionthat the atomic weight increases 2 units, or half the atomic weightof the a-particle, regularly in passing from one place to the nextin the system. The system, it is claimed, accommodates all theknown a-ray-giving radio-elements. These exactly fill the vacantplaces. However, i t may be pointed out that two new membershave since been recognised, and that in this system many of thevery definite analogies between the elements, which are brought outin the ordinary arrangement, are no longer recognisable. I nanother s y ~ t e m , ~ attempts are made t o build up the atomic weightsout of the two series 4n and 4n- 1, when n is an integer, an arrange-? Com1)are Ann. i:eport, 1906, 334.A.van dcr Rrork, Ph?ysi?;al. Zeztsdi., 1911, 12, 490 ; X I . , ii, 709.T. IVulf, Physihd. Zuitslh., 1911, 12, 497 ; A., ii, 709272 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ment due originally to Rydberg as far back as 1886, who pointedout that the elements possessing even valency fall in the first series,and those with odd valency fall in the second series mentioned.This would accord well with the idea that helium, or the a-particle,is a fundamental unit in the structure of atoms. About fortyelements have atomic weights in near accord with this view, thentimbers corresponding with each of the two series being equal.a- R ays.The scattering of a-particles in their passage through the atomsof matter5 possibly will give an experimental means of learningsomething of the nature of the atomic structure.The passage ofthe a-particle through the atoms of matter is the only knownphenomenon for which the dictum that two particles of mattercannot occupy the same space at the same time is not true, so thati t is -not unreasonable to hope that, after such passage, thea-particle may bear some evidence of what is inside of the otherwiseimpenetrable atoms it has traversed. A small fraction of theincident a-particles, about 1 in 20,000, is turned through an angleof 90° by impact on a gold leaf 0*00004 cm. thick, whereas themost probable angle of scattering is, under the same conditions, lessthan a degree. It is necessary to suppose that such large deflexionscannot be, as has hitherto been imagined, the result of a multitudeof successive small scatterings, for the chance of numerous successiveencounters, the effects of which all assist rather than cancel outone another, must be very small.The view that they are the resultof single encounters of necessity leads to the view that the atomis the seat of a much more intense electric field than in Sir J. J.Thornson’s theory of the atom, in which the sphere pf uniformpositive electrification is supposed to possess atomic dimensions.That is to say, as in the theory of atomic weights previouslydiscussed, a concentrated central charge is postulated, the effectsof the outer less concentrated equivalent opposite charge beingneglected. Preliminary measurements of the scattering suffered bythe a-particle confirm the general correctness of the theory workedout on this basis.On the other hand, the theory involves the con-sequence that, whereas in an encounter with a heavy atom, likethat of gold, the lbss of energy of the a-particle should be small,in the case. of a light atom, such as aluminium, the loss would beconsiderable, whilst in the case of a hydrogen atom it would appearthat in certain cases a more or less complete exchange of energyshould occur. These cases, however, have not yet been investigated.5 E. Rutherford, Phil. Mag., 1911, [vi], 21, 669; A., ii, 453RADIOACTIVITY. 273From previously published results 6 on the scattering with platinum,the magnitude of the central charge of the platinum atom isdeduced t o be about 100e.For different metals, if the magnitudeof the central charge is proportional to the atomic weight, it isdeduced that the relative scattering should be proportional to thetwethirds power of the atomic weight, and this agrees with theexperiments published. The results of Crowther with &rays7 arealso shown to be in general accord with the theory. The mostimportant change brought about by these experiments is the sub-stitution of a concentrated central charge of considerable magnitudefor the uniform sphere of electrification, of dimensions comparablewith the atomic diameter, hitherto generally assumed. This con-ception differs again from the one previously discussed, in that asingle central charge is postulated, whereas on the other view,although the constituent protyles are given single charges, in thecoalescence of these protyles into atoms, the central charges do notcoalesce, but, at least to some extent, retain their identity.Thelatter view renders easier the comprehension of the main radioactiveprocess, the expulsion of a helium atom, which, it is only reasonableto conclude, has existed in the parent atom previously, to a certainextent at least, as a distinct entity, before it is expelled.a-Rays of U raniu*n.-Special interest centres around the a-raysof uranium. If the two a-particles, known to be given out per atomof uranium in its first change, are not given out simultaneously,the so-called element uranium must consist of a mixture of twoelements, differing in atomic weight by 4 units, in a relative pro-portion the same as the relative periods of the two elements, and,as in so many other cases now known, non-separable by chemicalmethods.& It is altogether unlikely, in view of the low range ofthe uranium a-particles, which is the lowest known, that the periodof the element of lower atomic weight can be less than that ofionium, the element giving a-rays the next lowest in range.Theproportion therefore of the element of lower atomic weight cannottherefore be entirely insignificant, although it may not be mdrethan some grams to the ton as the minimum. On the other hand,there is no reason why it should not be a considerable proportion ofthe whole.The question whether the two a-particles of uranium can beexpelled simultaneously or with only short average intervals, up toa few seconds, between them seems t o have been definitely decidedin the negative by observations of the scintillations from a layerof uranium oxide enclosed between two zinc sulphide screens,Ann.Report, 1909, 237.8 Compare ibid., 1909, 259.ICEP.-VOL. VIII7 Ibid., 1910, 266.274 ANNUAL REPORTS ON THE PROGRESS OF CIIEMISTRP.observed by two observers with microscopes focussed on oppositeportion^.^ Under these conditions, pairs of simultaneous scin-tillations were not observed, neither was there any preponderanceof short intervals between the scintillations beyond that requiredby the theory of probabilities for a random distribution of intervals.On account of the shortness of their range, it is difficult t o decideby the usual methods whether the a-rays of uranium are homo-geneous.A new determination has been made by placing a zincsulphide screen centrally within a spherical glass flask of 10 cm.diameter, internally coated with a thin layer of uranium salt, andcounting the number of scintillations on the screen by the aid of alens outside the flask, for various pressures of air in the apparatua.10The range so determined a t ordinary temperature corresponded with2.68 cm. of air, which is in agreement with other recent deter-minations; but a sharp change in the direction of the curve, a t apoint corresponding with about half this range, indicates that theradiation may not be homogeneous.Evidence of the same characterwas also obtained by photography. A photographic film placedbehind a zinc sulphide screen inclined to a flat surface of uraniumshowed evidence of a decided change of density a t the point wherethe a-particles would travel about one-half of their complete range.If these results are confirmed, and it is proved that two sets ofa-particles are emitted, one with a range only one-half of the other,i t is to be expected that the element of lower atomic weight withthe a-rays of greater range would possess a period of the order ofonly home millions of years, and that its relative quantity, althoughnot negligible, will hardly be sufficient seriously to affect the deter-mined atomic weight of uranium. There are, however, grounds fornot accepting this result without further confirmation.Ranges of a-Rays.-A new set of determinations of the ranges ofvarious a-particles has been carried out by the ionisation method.11A film of the active substance was supported centrally in a globeinternally silvered, and the ionisation current through the gasplotted against the pressure of the gas.From the pressure a t whichthe a-rays just reach the walls of the flask, upward, the ionisationis constant, but at this pressure there is a sharp point of inflexion,and the ionisation a t lower pressures is proportional to pressure.The following table shows the results obtained with the uraniumseries. The temperature appreciably a,f€ects the range by affectingthe density of the air, and the results have therefore been calculatedfor both 15O and Oo.The last column gives the calculated initial9 E. Marsden and T. Barratt, Proc. London Phys. Soc , 1911, 23, [v], 367 ; A . ,1912, ii, 6. Compare Ann. Report, 1910, 257 and 258.lo A. Foch, Le IZndz'um, 1911, 8, 101 ; A., ii, 354.l1 I€. Geiger niitl J. 31. Nuttnll, Phil. Mag., 1911, [vi], 22, 613 ; A., ii, 953RADIOACTIVITY. 27 5velocity of the a-particle.under 760 mm. pressure:The ranges are expressed in cm. of airRange(13").Uranium ............... 2 '72Ioniuni .................. 3.00Radium .................. 3'30Polonium ............... 3 -77Thorium ............... 2'72Radiothorium ......... 3.87Range2.582-843-133-582.583'67(0").Initial velocityx 109 cm./sec.1 '511-561'611 *681-511 *70The result for uranium confirms the value of the range found inthe preceding investigation, but no evidence was obtained pointingto the existence of a second set of a-rays of lower range.It has long been known that, with a few apparent exceptions, thelonger the range of the a-rays the shorter is the period of thesubstance.That a mathematical relationship of some kind existsbetween the range and the period is shown by plotting thelogarithms of the ranges (or of the velocities, which are proportionalto the cubes of the ranges) against the logarithms of the periods.For those members for which both points are known in the uraniumseries a straight line results. If ionium, for which the range, butnot the period, is known, is placed on this line, the period corre-sponding with the range is nearly a million years.For the a-ray-giving product od radium-I: bhe period calculated from the rangeof the rays is only one-millionth of a second. A similar straightline relation holds in the actinium series, the line being parallel tothat in the uranium series, the ranges for corresponding periodsbeing, however, somewhat higher.An interesting new method for making visible the track of theindividual a-rays, and also of the &rays, through a gas is tocondense water-drops on the ions left behind in the paths of therays.12 As is well understood, the velocity of these rays is suchthat the gas molecules may be considered to be at rest by compari-son.At the instant the a-particle passes there is formed a cylin-drical column of ions in its track, of a diameter not greatly differentfrom the molecular diameter and of length corresponding with therange of the particle. This " columnar " ionisation with a-rays andthe great concentration o t the ions within the columns well explainsthe phenomenon of initial recombination encountered with a-rays.13The apparatus employed to render these columns visible is acylindrical expansion chamber, with flat, horizontal roof and floorof glass, coated with gelatin to render it electrically conducting andto prevent the formation of dew. The gelatin on the floor isblackened with Indian ink t o form a dark background. The a-raysl2 C. T. X.Wilson, Proc. Roy. Soc., 1911, A, 85, 285 ; A., ii, 565.l3 Ann. Report, 1909, 238.T 2’76 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.may be derived from the radium-tipped point of a spinthariscopewithin the chamber. An electric field between the roof and floorkeeps ths chamber clear of ions up to the moment of expansion.On expansion the individual tracks of the a-particles are clearlyseen on the dark background of the floor, when the chamber isbrightly illuminated. By illuminating the chamber with a powerfulspark, from 0.1 to 0.2 second after expansion, these tracks may bephotographed. Some of the tracks are remarkably sharply definedlines. Others show a doubling due to the incipient separation ofthe positive and negative ions by the field.With P-rays the straightthread-like tracks, due to the primary rays radiating from thesource, are crossed by others, due to secondary rays from the wallsof the chamber. In the ionisation produced by y-rays the largepart played by &rays is brought out, whilst with X-rays the thread-like tracks are rarely straight, but often have a beaded structure,which is perhaps due to the zigzag paths of the very low velocity&rays generated by X-rays. The evidence favours the view thaty- and X-ray ionisation is entirely an affair of the 6- and cathoderays they produce, and hopes are entertained that a definite proofof this difficult point may be reached by the new method.It has been established, by experiments with the a-particlesemitted from a radioactive solution, that the von Schweidler varia-tion is much greater in this case than in that of the a-rays from asolid preparation, a phenomenon which is to be expected on thepresent kinetic theory of the incessant violent motions possessedby the individual molecules of a liquid.The Brownian movementsof small suspended particles merely render this commotion visible,but it occurs universally, and to the same degree both in the liquidand gaseous states. Superimposed on the ordinary variation in theactual number of a-particles emitted in a short time-interval is asecond variation due to momentary changes of concentration ofthe radioactive molecules in the liquid, produced by their ownunco-ordirated movements.14A careful and accurate measurement 15 of the quantity of heliumproduced from a known quantity of radium, nearly 0.2 gram ofthe chloride, during periods of eighty-three and one hundred andtwenty-eight days, agreed in giving as the result that 0.156 C.C.ofhelium, at N.T.P., is formed every year per gram of radium(element) in equilibrium with its first three a-ray-producingproducts. This figure is subject to correction when an accepted14 T. Svedberg, Arkiv. Kern. Min. Geol., 1911, 4, No. 22.15 B. B. Boltwood and E. Rutheiford, Phil. Mng., 1911, [vi], 22, 586 ; A., ii, 953RADIOACTIVITY. 277standard of pure radium is available, the specimen employed being97.22 per cent. in terms of the Royal Society's radium. Thetheoretical rate, calculated from the number of a-particles expelled,which is 1-36 x lolo per gram per second, is 158 cu.mm.per year,assuming that helium has a monatomic molecule. The number ofmolecules in a C.C. of gas under standard conditions deduced witha minimum of assumption from these results is 2-69 x 1019, andthe value of Avogadro's constant, or the number of molecules inthe mole of any gas, is almost exactly 7 x loB.A preparation of ionium,le weighing 1.8 grams, and of a-activity3000 times uranium, in one hundred and twenty-five days generated0-031 cu.mm. of helium. This is little more than half the theoreti-cal amount (0.0595 cu.mm.) calculated from the number ofa-particles expelled, but the helium was removed by ignition of thepreparation in a Jena-glass tube, and some may have been retained.Similarly with a polonium preparation,l7 initially of amount equalt o that in equilibrium with 4.1 milligrams of radium, the observedproduction of helium, 0.009 cu.mm.in one hundred and twenty-eightdays, is only about one-fourth of the calculated value. Hereundoubtedly a part of the helium would embed itself in the copperplate on which the polonium was deposited.The red fluorspar of Ivitgut, Greenland,lB was separated fromthe adjacent cryolite, and divided into a lighter and heavierfraction. The lighter part contained 4 per cent. of rare earths,including thoria and the helium. The heavier part consisted of aniron and copper mineral containing uranium and lead. The conclu-sion was drawn that the fluorspar, but not the cryolite, is able toabsorb and retain the helium.Similarly, helium has been detectedin the insoluble matrix in which Portuguese autunite occurs, afterthe mineral has been dissolved out by acid.19 The gas evolved byignition was estimated to contain about the same amount ofhelium as the gas evolved on solution of the original mineral inacids. The conclusion was drawn that the purer autunite is, andthe less earthy matrix mixed with it, the less helium it contains,and therefore that the helium content is not connected with theage of the mineral. It is possible, of course, that a radioactivemineral may be permeable to the helium produced within it andbe encased in a matrix which is not so permeable, with the resultthat the matrix, but not the mineral, may be found t o containhelium; but the attempts which have been made to show that18 B.B. Boltwood, Proc. Boy. Soc., 1911, A, 85, 77; A., ii, 369.B. €3. Boltwood and E. Rutherford, Phil. Mag., 1911, [vi], 22, 586 ; A., ii, 953.l8 Ann. Report, 1907, 323 ; Hans Langc, Zeitsch. Natz~rwiss. Halle, 1910, 82 ;l9 A. Piutti, Le kdiz6rn, 1911, 8, 204 ; A,, ii, 565.*4., ii, 499278 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.substances may selectively absorb helium, so vitiating this methodof estimating geological age, are unconvincing.208-R "y 8.1mporta.nt developments have occurred in connexion with thenature of the P-rays. The determination of the magnetic spec-trum 21 under proper conditions has established that the apparentheterogeneity of, for example, the &rays of the radium activedeposit originating in the disintegration of radium-B and -C isdue, in the first place, to the existence of a large number of separatetypes of rays each homogeneous as regards velocity when expelled,and, in the second place, to the conversion of these initially homo-geneous rays into heterogeneous rays when they traverse anyabsorbing material.The main idea, therefore, that in each disin-tegration the &particles, like the a-particles, are expelled withdefinite characteristic velocities, is borne out, but the further viewthat a single disintegration gives only one homogeneous type ofrays, and that, therefore, a complex radiation is evidence of acomplex series of changes, is not substantiated.The effect of absorbing screens on the velocity of &rays seemsto depend on the magnitude of the velocity of the rays.The slowerfl-rays, moving at a velocity up to, perhaps, 70-80 per cent. ofthat of light, in passage through an absorbing medium sufferreduction of the velocity as ilr whole without loss of homogeneity,and therefore there is no difficulty with them in obtaining fairlysharp lines in the magnetic spectrum. The &rays moving withvelocities greater than these usually appear as heterogeneous, andneither their velocity nor their degree of heterogeneity is alteredby passage through absorbing screens.22Of the first class of low-velocity rays, radium itself gives twotypes, of which the velocities, in terms of that of light, have beenprovisionally estimated to be 0.65 and 0.52.23 Radium-B gives fivetypes of velocities : 0.74, 0.69, 0.63, 0.41, and 0-36.24 Radium-Dgives two types of velocities: 0.39 and 0.33.25 Thorium-2326 givesone type of velocity, 0.63, and there are three other types of veloci-ties: 0.72 (feeble), 0.36, and 0.29, due either to thorium-B or -B.2o Le Badium, 1911, 8 , 1 3 ; A., ii, 8 8 ; R.J. Strutt, A7UtZ6re, 1E10, 85, 6 .22 0. v. Raeyer, 0. Hahn, and L. Meitner, Physikal. Zeitseh., 1911, 12, 273 ;23 Ibid., 1099 ; A . , 1912, ii, 7.25 Bid., and 0. Hahn and L. Meitner, Physiknl. Ze'Eit~~h., 1511, 12, 378 ; A . ,Compare Ann. Report, 1910, 265.A., ii, 567.Ibid.ii, 567.Throughout the new nomenclature (p. 285);is adoptedRADIOAC'I'IVITY. 279The main type of P-rays of thorium-D belong to the other class ofhigh-velocity rays, and have not yet been resolved.They appearheterogeneous, with velocity between 0.93 and 0.95.27 The high-velocity P-rays of radium-C are the only ones of the class so farresolved. Four types are present, with velocities 0.98, 0.94, 0.86,and 0*80.28The measurements given of the velocities of the &rays of radium-Band -G were done by means of a silver wire coated with the twosubstances together, and of a nickel wire coated with radium-C only,so that no previous absorption of the rays occurred. The priority,however, of resolving the @-rays of radium belongs to an independentinvestigator,2Q with the radium emanation contained in a capillaryglass tube just sufficiently thick in the walls to absorb a-rays.Photographs of the magnetic spectrum showed that the &rays hadbeen sorted into seven types, the two lowest velocity types ofradium-B probably not having escaped from the tube.The veloci-ties obtained agree very closely with those given, but the rays dueto radium-R and -C separately were not distinguished.I n a later communication 30 very accurate measurements are givenof the seven strong beams given by radium-B and -C together. Theirvelocities are: 0.615, 0.682, 0.735, 0.786, 0-862, 0.940, and 0.957.The first four are from radium-B, and the last three from radium-C,according to the work already discussed. The first three compriserays differing in velocity about 1 per cent. on either side of themean velocity, but the others are quite sharp.I n addition, no lessthan fourteen other beams of P-rays, equally definite but compara-tively feeble, have been recognised, alternating fairly regularlywith the seven strong beams. Also, two other beams of extremelyhigh velocity, and in consequence very difficult to deviate, havebeen made out. Such &rays resemble the y-rays in affecting thephotographic plate but feebly. The first beam is complex, andconsists of from three to five separate beams, with mean velocity98.8 per cent. of that of light and value-for H p (the memure oftheir magnetic deviability) 11,200. The last beam has the meanvelocity no less than 99-6 per cent. and mean value of H p 18,100,although for some of the rays 99-8 per cent.and over 26,000 arethe figures given. This confirms the work of previous investigatorsthat it is impossible completely to deviate the &rays of radium, andalso of uranium, in a magnet.ic field, and that some of the P-rays37 0. v. Baeyer, 0. Hahn, and L. Meitner, Physzknl. Zeitsch., 1911, 12, 273 ;28 Ibid., 1099; A . , 1912, ii, 7.29 J. Dangsz, Uomnpf. rwd., 1911, 153, 339 : A . , ii, 840.30 Ibid., 1066.A., ii, 567 ; ibid., 1099 ; A . , 1912, ii, 7280 AKNUAL REPORTS ON THE PROGRESS OF CHEMISTRYin each case must possess velocities very nearly indeed approachingthat of light itself .s1The only radioactive substances decomposing truly raylessly aremesothorium-1 and actinium. Most of those at first thought to berayless, for example, radium-D and the -B members of the threeactive deposits, have been shown to give low-velocity &rays. Someof these P-rays do not surpass in velocity the artificially generatedcathode-rays, and in penetrating power are not much superior tothe a-rays. To distinguish them from the penetrating &rays, towhich the name wits first applied, the symbol ‘‘ (@)-rays ” haa beenemployed.y-Rayr.Attempts hitherto made to generate y-rays by the impact of&rays of radium on metals, in the same way as X-rays are generatedfrom cathode-rays, have not been successful, any such effect beingtoo small to be detected with certainty. By using the &rays of apreparation of radium-&’, the y-rays of which are extraordinarilyfeeble, such a generation of y-rays by the &rays has been put intoevidence, although it is feeble.Bringing a radiator of lead undera layer of radium-E placed beneath an electroscope, the base ofwhich consisted of sufficient cardboard and aluminium to absorbthe P-rays completely, gave an increased leak, and that this wasdue to the B-rays was shown by covering the upper surface of theradiator with sufficient paper ta absorb all or a known proportionof the &rays, when the increase of the leak in the electroscope wasreduced correspondingly. The secondary y-radiation increases inamount with the atomic weight of the radiator, and i s roughlyproportional to it. The secondary y-rays formed are the more easilyabsorbed the greater the atomic weight of the absorbing metal, asis the case with X-rays. It is surmised that the y-rays of radium-Emay be entirely of secondary origin, and the suggestion is madethat the y-rays of uranium-X may also be secondary. The lattersuggestion was made without any examination of the rays inquestion, and is unfounded.82An investigation of the effect of temperature on the absorption-coefficient of iron for the y-rays of radium, between 600° and 700°and room temperature, showed that temperature exerts no directinfluence. A small diminution of the ooescient, about 0-002 percent.per degree rise of temperature, is almost exactly what is to beexpected from the expansion of the iron with heat and its conse-quent decrease of density and increase of thi~kness.3~a1 Ann.Report, 1909, 241.32 J. A. Gray, Proc. Boy. floe., 1911, A, 85, 131; A., ii, 355.33 W. Wilson, Phil, Mag., 1911, [vi], 21, 532R A DI 0 A CTI V ITY. 281The coefficient of absorption of the y-rays of radium-C in air a t2 2 O and 750 mm. has been experimentally determined to be0.45 x 10-4.34 This constant has an importance in connexion withthe earth's penetrating radiation.b-Ray$.The view is gaining ground that the electrons, or &rays, emittedwhen a metal plate is struck by a-particles are due to the ionisationof the metallic atoms by a process identical with that whichoccurs in a gas when a-rays t'raverse it. The emission of b-rays fromvery thin aluminium and gold leaves in a high vacuum has beenmeasured for different parts of the range of the a-particle.Thecurves connecting the emission of &rays and the range of thea-particle are completely analogous in form to the Bragg curveconnecting the ionisation in gases and the range.35 Some points stillremain to be cleared up; for example, aluminium and gold showedpractically the same curve, whereas, since heavy atoms are moreeffective in retarding a-rays at the commencement of their paththan light atorns,36 certain differences between the forms of the twocurves were anticipated. The similarity between the two metals,which differ so greatly in atomic weight, raises the question whetherthe &particles result from the metal or from a film of condensedgas of the same naturc in each case. With the a-rays of thorium-C,which are known to comprise two sets of a-rays of greatly differentranges, the b-ray-range curves showed the two " knees " character-istic of the ionisation-range curve.Certain negative tentative conclusions with regard t o the natureof the b-rays have been put forward, which, if confirmed, are ofgreat importance in regard to the nature of gaseous ionisation; thusthe speed of the &particles and their number is apparently indepen-dent of the speed of the a-particle and of the nature of the metalfrom which they are emitted.I n this work about 10 b-particleawere emitted per a-particle of polonium.37 In another research thenumber 17 was obtained from brass, whereas the copper plate onwhich the polonium was deposited expelled about 60 &particles pera-particle.The kinetic energy of each kind was similar, and theirpenetrating power was found to be from 1/7th t o 1111th of thatof the a-particle of polonium.38V. F. ReQs, Sitzzmgsbcr. K. AEad. JViss. Wien., July, 1911, 120, Ha.y5 H. A. Bum*tead, Phil. Mag., 1911, [vi], 22, 907 : A . , 1912, ii, 8.36 Compare Ann. Report, 1909, 237.37 .F. Camy~lell, Phil. N a y . , 1911, [vi], 22, 276; A., ii, 841.38 F. Hausor, Pha~ih-al, Zeitsch., 1-911, 12, 466 ; A., ii, 685282 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Zonira t ion.No claim is made in these reports for anything like a completeaccount of the progress ma#de in the great subject of ionisation,which is distinct from that of radioactivity although closely con-nected with it, as to do it, and the similar subject of X-rays, justicean unduly large part of the available space would be necessary.Some brief references only can be given.The view that the ionisation produced by an a-particle is propor-tional to the loss of energy suffered by the a-particle has beenconfirmed, but the amount of energy required to produce an ionis not the same for all gases, and varies from 1.01 for hydrogen to0.73 for cwbon dioxide (air being taken as unity).The heavierand more complex molecules are somewhat more easily ionised thanthe light and simple ones. With regard to P-rays, /3-ray-givingproducts have been selected which can be obtained in equilibriumwith an a-raygiving product. I f per a-particle emitted, and there-fore per atom disintegrating, only one &particle resulted in allcases, from measurements of the ionisation and number ofa-particles could be deduced the relative ionisation caused perB-particle in the dserent cases.Or, if it be assumed that in eachcase the ionisation produced per &particle is of the same order, thenthe measuremenix will afford an idea of the relative number of&rays expelled per atom of the 8-ray-giving substance disintegrat-ing. This line of attack makes it appear that thorium-D andactinium-D give twice as many &particles per atom disintegratingas uranium-X and radium-E, whilst radium-C is intermediate.39This reasoning as regards thorium-D involves the assumption thattwo a-particles are expelled, one each per atom of thorium-C, and-Cz, which has subsequently been shown not to be the case, the twoproducts before supposed to be successive being more probablysimultaneous (p.289). If during the disintegration only onea-particle is expelled per atom of thorium-B disintegrating, thenboth the products thorium-C, and -C, must give thorium-D, inorder that that member should expel one &particle per atomdisintegrating, which is an interesting but somewhat improbableconclusion.^^ On the aaaumption that the radium-E atom given one6-particle, about 67 ions a m produeed in air per cm. of path per&particle. In another investigation, in which the same assumptionwas made for the radium-C atom, the number 48 wag obtained, or1.2 x lo* ions in the complete path. On the assumption that oneH. Geiger and A.F. Kovarik, Phil. Mag., 1911, [vi], 22, 604; A, ii, 954 ;W. Wilson, PYOC. Roy. Soe., 1911, A, 85, 240; A , , ii, 516.4o E. Marsden and T. Barratt, Proc. London Phys. Soc., 1911, 24, i, 50RADIOACTIVITY. 283y-ray, considered as an entity, is evolved from radium-C perP-particle, the corresponding numbers for the y-ray are 1.2 and3 x 104. If the heating effects and ionisations are proportional, the&rays contribute 2 calories, the y-rays 4.5 calories of the total110 calories emitted per hour per gram of r a d i ~ m . ~ lWonderful developmbnts have been made in the cloud method ofmeasuring the atomic charge by the us0 of non-volatile liquids,single droplets of which have been kept under continuous observ*tion for hours, while they from time to time attracted positive ornegative charges from the ionised gas, and abruptly altered theirvelocity under the opposed actions of gravity and an electric field.The mean value, 4.9016 x 10-1O E.S.U., has been deduced for theatomic charge, t,he number of such charges on the droplet, whichdroplet was comparatively large, varying from 4 to 17 during oneobservation.42 Arising out of this work the conclusion was drawnthat the primary act of ionisation always results in singly charged,or “univalent,” ions, and that multiple charges on ions result bysubsequent actions, a conclusion which has been called into ques-tion.43 The mass of the gaseous ion has also been the subject ofimportant invest,igation,44 whilst a re-investigation of the effect oftemperature has shown that even when the mean kinetic energy oftranslation of the molecule is doubled, its ability to be ionised ienot altered by 0.1 per cent.45 The view that the charge on an ionwanders from molecule to molecule, so that for only a p-art of thetime i t is charged, the observed mobility being only a mean valuefor different charged molecules, has been tested by an ingeniousmethod and been found wanting.46New Short-lived a-Ray Products. Changes of Nomenclature.The discovery of the existence of double scintillations with thea-rays of the actinium emanation, and of pairs of successive scin-tillations, at about 0.2 second interval, with the a-rays of thethorium emanation,47 has now been followed up, and proof obtainedthat in each case a new a-ray product of the emanation exists inthe series intermediate between it and what has hitherto beentermed thorium-A and actinium-d.A n examination of the rangeA. S. Eve, Phil. Mag., 1911, [vi], 22, 551 ; A., ii, 956.42 R. A. Millikan, Le Radium, 1910, 7, 345 ; A , , ii, 175.43 R. A. Millikan and H. Fletcher, Phil. Mag., 1911, [vi], 21, i 5 3 ; A , , ii, 573 ;J. 5. Townsend, Phil. Mag., 1911, [vi], 22, 204; A . , ii, 686.44 J. S. Townsend, Proc. Eoy. Soc., 1911, A, 85, 25 ; A , , ii, 355 ; W. Duane,Compt. m i d , 1911, 153, 336 ; A . , ii, 839.-15 J. H. Clo, Lo Eadium, 1911, 8, 108 ; A . , ii, 355.J6 ,I. Franckand 1,. Meitner, Rer. Derrt. physikal. Ges., 1911, 13, 671 ; A., ii, 968.A m .Report: 1910, 257284 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of the a-particle of actinium emanation revealed the existence oftwo sets of a-rays.48 The range of the a-ray of the emanation itselfis 5.7 cm. of air, that of its evanescent product 6.5 cm., that ofactinium-A‘ 4.4 cm., and of the actinium active deposit (AcC) 5.4 cm.These values correct previously given values.49 Using a tube pro.vided with a thin mica window, in which actinium emanation circu-lated, and containing an electrode so arranged that no a-rayscoming from this electrode could escape from the window, it wasarranged that only the a-rays of longest range, 6.5 cm., could reachan external screen placed outside the mica window. The applica-tion of it field, charging the electrode negatively, instantly resultedin a greatly reduced number of scintillations on the screen, whilstthe interruption of the field instantly restored the number to thefirst value.Hence the evanescent product of the actinium emaniLtion behaves like a non-volatile product of the “active deposit”type, being attracted to a negatively charged electrode. From thefield necessary to reduce the nmnber of scintillations to a determinedextent, a rough but, as it proved, extraordinary close estimate ofthe period of the product could be obtained. This was only of theorder of 1/500th second.Two methods of putting into evidence this extraordinarily quick-changing product, and abo the similar but less shorblived newproduct of the thorium emanation, have been devised.An electrodecoated with zinc sulphide immersed in either of the emanationsinstantly glows when made negative with respect to the vessel, andas instantly ceases to glow when discharged. Indeed, the actiniumproduct was observed in a similar manner eight years before.50 Theconclusion was then drawn that the rays from the emanation wereattracted by a negatively charged object, and in this respect werepeculiar, the name E-rays being given to them. Actually, ofcourse, the product attracted to the negative electrode changes, andexpels its a-rays so rapidly after deposition that to the unaidedeye it appears as i f it were the rays themselves, rather than theray-producing prosducts, which are attracted by the field. Bydriving with a motor an endless wire, negatively charged, throughholes in the ebonite stoppers of a cylinder containing a source ofeither of the emanations, it can be shown that as long as themotor is working the wire gives out a strong a-radiation as itleaves the cylinder.This activity and its decay as the wire travelsfrom the elinder can be studied by means of a zinc sulphidescreen.6l48 H. Geiger, Phil. Nag., 1911, [vi], 22, 201 ; A . , ii, 683.49 Ann. &port, 1906, 343.g1 E. Rutherford aiid H. Geiger, Phil. Mag., 1911, [vi]> 22, 621 ; A . , ii, 955.50 Gibsel, Rer., 1903, 36, 342; A., 1903, ii, 193RADIO ACT1 VITY. 285The periode of these two new a-ray-giving products have beenaccurately determined by a, rotating disk method.52 On the peri-phery of the metal disk presses a sector-shaped box with its edgeslined with velvet and containing a, source of either of the emana-tions.Inside the box a wire gauge is positively charged, repellingthe product of the emanation on to the disk. Two sector-shapedionisation chambers are mounted opposite other portions of theperiphery, the faces opposite the rotating disk being covered withgoldbeater’s skin and aluminium leaf. From the relative ionisatioiiin these two chambers, their angular distance apart and the speedof the disk, the period of the products can be determined. Thatfrom thorium proved to have a half-period of 0.145 second, andthat from actinium 0.002 second.These short-lived a-ray-giving products, standing as they do inter-mediate between the emanation and the (p)-ray or almost raylessnext product of the active depod, both of which are much longerlived, are obviously in every respect analogous to radium-A in theradium active deposit.The half-period of radium-A, about threeminutes, although short, is much longer than those of the newproducts, and radium-A has always been recognised as a separatemember of the series. Hence it is necessary to alter the nomencla-ture of the thorium and actinium active deposit series, and to giveto the new substances the names actinium-A and thorium-A, TheA-members in each of the three cases are now short-lived, and givea-rays. What have before been termed thorium-A and actinium-Aare now called thorium-B and. actinium-B. These are in everyrespect analogous t o radium-B.I n each case the B-member is thelongest-lived of the active deposit group, and gives only relativelyinsignificant (P)-radiation. The next members of the two serieshitherto termed thorium (R and C) and actinium-B are now,therefore, termed thorium-C, and -C2 and actinium-C, or -C, and -C2.The evidence of two products in the thorium series is indirect, andconfined to the two sets of a-rays emitted. I n the case of actinium,the evidence is of similar nature but less definite. These productsare thus analogous to radium-C. The C-members give a-rays, andare shorter lived than the B-members. Now an unfortunate differ-ence occurs. The next or D-members of the active deposits ofactinium and thorium are relatively short-lived, and the powerful8- and y-rays of the active deposits come entirely from theseD-members. I n the radium active deposit, radium8 has been shownto be complex (p.286). What is probably a branch product, calledradiu-C,, gives only B- and y-rays, and no a-rays. The a-ray-givingradium-C, unlike the other C-members, seems to give 8- and y-raysH. G. J. Moseley and K. Pajans, PhiE. Nag., 1911, [vi], 22, 629 ; A . , ii, 956286 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.also. Hence the next member, radium-D, which is the well knownlong-lived member, giving only insignificant @)-rays, and oftencalled radio-lead, is not analogous to actinium-D amd thorium-D,but to their products, the stable, unknown, ultimate members ofI1Ionium(5x 104 t o 106 @+Odyears?)Radium(1,500 years)Emanation e0 68(5.57 days)RadiumA(4.3 minutes)111Radium C , @))O O((as.I minutes)(1.9 Radium minutes) C, [ 2:;:~Radium D ( U O ~ -+e@)(24 years 7)Radium E kf.9 4 + yRadium F(202 days)Radium G(probably @lead)(7.25 days) 61ActiniumRadio-actinium(28.1 days)Actinium X(15 days)Emanation(5.6 seconds)Actinium A(0.oozgsecond)Actinium B(52.1 minutes)Actinium C ,b. xominutes)Actinium C, (?)Actinicm D(6.83 minutes)Actinium E(Unknown)Thoriumyears ?)(4X I0lo 0-01Emanation o-,o aD(76 seconds)1Thorium A(0.203 second) 0-0 d.Thorium B1(15.3 hours) od* '' 1Thorium C1(79 minutes)Thorium 0) C2 (El 1Thorium D(4.5 minutes)Thorium E(Unknown)these series. The changes of nomenclature, whilst of necessity veryconfusing, result on the whole in a much better system, in whichthe close analogies between the successive members of the threeactive depoeits are brought out, the analogous members now havinganalogous designations, with the exception just noted of radium-D.Above has been reproduced, by the kind permission of thRADIOACTIVITY. 287publishers, Messrs.Longmans, Green and Co., a chart from a recentbook,63 showing the disintegration series of the radieelements so faras they are a t present known. The periods given are the periods ofaverage life, which are 1.45 times the half-period.Multiple Disintegration.RadiumC, and -C,.-The idea that in addition to the maindisintegration series branch or subsidiary series may occur, haa longbeen considered t o be the best means of explaining the formationof the actinium series.Actinium, since it always occurs in constantrelative amount in the uranium minerals, must be looked upon aaderived in some way from uranium, but its small relative quantityin comparison with the other members of the uranium seriesprecludes the possibility that it can form an intermediate memberof the main seriw.64 The first experimental evidence of the forma-tion of branch series was obtained during the year in a study ofradium-C. The complexity of this member, and the existence of asubsequent product, termed radium-C,, of half-period between 1 and2.5 minutes, and separable by recoil methods, was already known.6sIn the new w6rk56 much larger quantities of radium were available.The feature about the recoil of radium-C2 from the active depositis the extraordinarily minute amount of the product so obtained,which indicates that it is formed in a P-ray rather than in an u-raychange.From this, erroneously, it had been concluded thatradium-C, gives the 8- and y-rays, aad that radium-C, gives thea-rays. However, radium-C,, the half-period of which wm foundas the result of some fifty determinations to be 1.38 minutes, givesno a-rays, but only &rays identical in penetrating power to thosefurnished by radium4 as a whole. Neither doee radium-C2 giverise to any a-ray-giving product on disintegration. A small quantityof ordinary radium-C, giving u-, B-, and y-rays, and having the19.5 minutes half-period, is, it is true, dwaye recoiled with theradium-C,, but i t wils proved to be present from the start.Theproduct of radium-C2 remains unknown. Hence, on the one hand,the a-rays must come from radium-C,, and on the other, radium$,cannot be the product of the a-ray change of radiumC,, for, if itwere so, a considerable fraction of the whole product should berecoiled. The B-activity of the recoil product is, however, onlyabout 1/20,000th of that of the source. What, then, is the product5J " Monographs of Inorganic and Physical Chemistry," edited by ProfessorAlexander Find1:ry. " The Chemistry of the Radio-Element.," by Frederick Soddy.Longmans, Green and Co. 1911.54 Ann.Report, 1909, 260, 55 rm., 1909, 248.BG K. Fajans, Phys.z'ktc2. Zeitsch., 1911, 12, 369 ; A . , ii, 569258 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of the a-ray change of radium-C, a considerable fraction of whichmust recoil a t the moment of its formation? Experiments provedthat it is radium-D. Plates left on to collect the recoil product ofradium-C whilst that substance completely decayed, were inactive atfirst, but developed a- and &activity a t the rate characteristic of theformation of radium-F and -E from radium-D. I n this way it wasfound that about 25 per cent. of the total number of radium-Datoms formed were received by recoil on the plate. It follows thatradium-D must be the direct product of the a-ray change ofradium-C,, and that therefore radium-C, cannot be an intermediateproduct in the main radium-polonium disintegration series.Theproportion of the number of radium-C, atoms changing respectivelyinto radium-C2 and into radium-D, the kind of radiation accom-panying the two modes of disintegration, and the nature of theproduct of radium-C2 remain unanswered problems. It appears thatradium-C, accounts for only a small part of the total &radiation ofradium-C. Possibly the product of radium-C2 may prove to beactinium. I n addition, it must bo remembered that it is veryunlikely that the a-rays of radium-C, come directly from radium-C,,for the half-period of this substance ia 19.5 minutes, whereas theperiod calculated from the range of the a-particle is a millionthof a second (p.275).The ice having, as it were, been broken by the foregoing research,if is natural that the same explanation of an atom being capableof disintegration in more than one mode should be used as a wayof escape in other cases, not amenable to other explanation, butthe evidence in these other cases is still far from complete.Urunium-Y.-Diff erences have been observed in uranium-X pre-parations separated from carefully purified uranium salts in differentways. In some there is a larger proportion of the very feeblypenetrating (@-radiation than in others, and this excess decayedwith the half-period of 1.5 days, whereas the half-period ofuranium-X, and of the decay of the main penetrating @-rays, andalso of the y-rays, is 24.6 days.The name uranium-P was givento the product of half-period 1.5 days. Uranium-X, separated froma uranium solution by precipitating barium sulphate therein,behaved normally; but when separated by adding an iron salt,and precipitating it by boiling, there was obtained a rapid initialfall in the decay curve for the uncovered preparation, but a normaldecay curve when the measurements are taken through 0.01 cm. ormore of aluminium. A very feeble a-radiation, decaying also, sofar as could be determined, with the 1.5 days half-period, was alsodetected by the scintillation method. The feebleness of this a-radia-tion in comparison with the (@)-radiation is unusual. It was neveRADIOACTIVITY. 289found poeuible to separate more than a very small amount of thenew product, and the recovery curve of uranium from whichuranium-X had been separated was always normal, and showed noevidence of existence of the new member.I n absence of otherexplanation, it is considered that uranium-X and -P may be simul-taneous products of uranium, the uranium-P being formed in rela-tively minute quantity.67 The question arises whether the short-period member, uranium-P, does not give rise to some of the 6-raysmoving with velocity approaching closely that of light (p.. 279), foran experiment has been recorded in which a rapid diminution ofthis part of the &radiation of a preparation of uranium-X tookplace during the first few hours, the y-radiation remaining constant01-er the same interval.68Thorium-C1 and -C,.-The evidence for the complexity of thissubstance depends on the two sets of a-rays of different rangeemitted.59 Since one of these aeh of a-rays has the longest knownrange, i t has always been surmised that the change in which itresulted was of immeasurably short period, so that the productproducing it could not be separately distinguished from its parent.Were this so, thorium-C, like the emanations of actinium andthorium, should give rise im double scintillations.An examin&tion,eO however, disproved this. The intervals between the succes-sive scintillations are such as, in the main, accord with the theoryof probability, and it is therefore not possible that thorium-C2 canbe a direct, very-short-lived product of thorium-C,.The failure of recoil methods t o separate thorium-C2 proves thatneither can it be produced from thorium-C, through an intermedi-ate parent.The conclusion has been drawn that thorium-C, andthe parent of thorium-C2 (the period of which, as calculated fromthe range of its a-particle, can only be immeasurably short and ofthe order of 10-l2 second) are the simultaneous products ofthorium-B. I n support of this i t has been found that of the twosets of a-rays given by the C-member, 64.6 per cent. have thelonger range, and 35.4 per cent. the shorter range, whereas if thetwo products were successive the numbers of a-rays ought to be thesame for each. This ratio does not alter as the active materialdecays. The fact also that the total a-radiation of pure thorium-(7decays exponentially, shows that, on this hypothesis, the periodsof thorium-C, and the parent of thorium-C, must be identical.Alsowe have seen (p. 282) that there is some reason to believe that bothmembers give the same product, thorium-D. The nearness of the57 C . X. Antniloff, PAiZ. J/ug , 7911, [vi], 22, 419 ; R . , ii, 844.sy Soddy, ibid., 1909, [vi], 18, 862 ; A . , 1910, ii, 10.59 A m . Iteport, 1906, 342.E. Marsden and T. Bsrratt, F'TOC. London Phys. Soc., 1911, 24, i, 50.REP.-VOL. VIII 290 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ratio of the numbers of the two sets of a-particles to 2 : 1 is sugges-tive, however, for if thorium-C, gave two a-particles per atomdisintegrating to only one given by thorium-C',, the products stillmight be successive.This, however, involves the view that theemanation and thorium-A both give three a-particles per atomdisintegrating. Obviously experiment and reasoning have for thetime being reached a position of stale-mate.In the case of the actinium active deposit also, no double scintil-lations were observed, but here the evidence in favour of twoproducts is altogether less definite.It has been pointed out that the rule that in the radium seriesone a-pa rticle is expelled per atom disintegrating, where the disin-tegration is accompanied by a-rays, does not appear to be followedin the thorium and actinium series.d1 The recent advances in ourknowledge of the two latter series do much to remove this difference.Taking into account the new short-lived A-products of the activedeposits, and assuming the simultaneous production of the Cr- andC2-products just discussed, the facts are consistent with the viewthat the emanations, the A-products, and the C-products may a11give only one a-particle per atom disintegrating, and so in thisrespect fall into line with the radium series.The Periods of the Longer-lived Radio-elements.Actinium, concerning the period of which no data whatever havebeen available, if the progress of time confirms Borne recentobservations, may prove to be far from a long-lived radieelement.62I n a research which included also the variation with time of theactivity of uranium, radium, and radium-D, it was found that theactivity o,f an old preparation of actinium, as measured by the&rays, had decreased by about 10 per cent.in the last three years,a rate of decay which, if continued, indicates a period of averagelife of the order of only thirty years. The individual measure-ments were inexplicably irregular, as compared with thme of theother substances, and the means of a large number of observationswere compared. Another &planation also suggests itself from thealmost complete analogy between the actinium and thorium series.The B-activity of thorium compounds freshly prepared from mineralsdecays, as is well known, for two years to a minimum, owing to thedecay of the radiothorium separated always quantitatively with thethorium, in the absence of its immediate parent, mesothorium,which is separated quantitatively from the thorium.The periodof radioactinium, however, is too short to explain the observedta Ann. Ileport, 1909, 236.G2 Mme. Curie, Le Ilndizbrn, 1911, 8, 353 ; A . , ii, 1047RADIOACTIVITY. 291decay, and, in addition, radioacthiurn, being separable fromactinium, is in this respect not analogous t o radiothorium. Toaccount for the decay, two new members between actinium and r a d bactinium, the first separable, the second non-eeparable, from theactinium, must be postulated. The alternative explanation, thatactinium has a period of only thirty years, cmriea with it thecorollary that its reproduction should be easily detectable, and thishas 80 fax not been observed.No variation of activity was observed in the a-radiation ofuranium oxide.The &rap of radium showed a ateady increase ofalmost 2.5 per cent. per year, due doubtless t o the gradualformation of radium-D. Both the a- and @-rays of radium-D, threeyears after preparation, showed for the next two years a regulardecay corresponding with a period of average life of about 25 years.The period the least known, next to thqt of actinium, is theperiod of ionium. An upper and lower limit of 30,000 and amillion years, respectively, have been assigned.63 The first isarrived a t from the failure, so far, to detect with certainty theproduction of radium from uranium, on the assumption that ioniumis the only long-lived intermediate product. The latter followsfrom the weight of “thorium oxide” separated by Auer vonWelsbach from the residues of aome tons of pitchblende,64 on theassumption that the “ thorium oxide ” w~is in reality pure “ ioniumoxide,” and that all the ionium present in the mineral was actuallyseparated.To the extent the first assumption is wrong the periodwould be reduced, and t o the extent the second is wrong it wouldbe increased. The range of the a-rays of ionium, aa alreadyindicated, corresponds with the period of nearly a million years(p. 275).General Properties and Methods of Preparation of theRadio-elements.It is often essential to be able to separate a radio-element withoutappreciable quantities of inactive matter, as in the separation ofthe active deposits from the emanations, so that the radiations shallbe emitted without first having had to pass through absorbingmaterial.Much useful practical information of two of the commofimethods, the electrolysis of solutions, and the deposition of theactive material by immersing its solution in a less “ noble ” metal,has recently been published.65 With regard to the first method, asilver cathode and platinum anode connected to a 220 volt circuitc,3 F. Soddy, Le Endizrm, 1910, 7, 297.64 L. Meitner, PhysikaZ. Zeitsch., 1911, 12, 1094 ; A . , 1912, ii, 10.Ann. Report, 1910, 276.U.292 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.through a 25 c.p. carbon lamp, and placed about 1 mm. apart inthe rapidly boiling solution of the active substance, the volume ofwhich is kept as small as possible, are the conditions recommended.From slightly acid solutions of the respective active deposits,electrolysis separates radium-U and -C together, E and F together,thorium-B sometimes with a little thorium-C, and actinium-B withsome actinium-C and -D.Before electrolysis, if desired, radium-C,thorium-C, and actinium-C may all be quantitatively separated inthe pure state by immersing in the solutions a nickel plate, whilstradium-$' may be removed similarly by bismuth.The D-products of thorium and actinium giving P- and y-raysare most easily prepared by recoil methods. Actinium-D, it shouldbe noted, has been given somewhat too low a period. A newdetermination, from 50 curves, gave the mean value for the half-period of 4-71 minutes.66I n the preparation of mesothorium-2, the mesothorium solutionis precipitated by ammonia after adding a trace of iron.Afterdaily precipitations for a few days, the radiothorium and thorium-Xare got rid of, and there is then obtained only mesothorium-2 anda little thorium-B with the iron. Electrolytis of the acid solutionwith a platinum cathode first separates the iron and thorium-B.The mesothorium-2 can then be deposited electrolytically on a silvercathode from the boiling, nearly neutralised solution.A method which is claimed to be of general utility in theseparation of radioactive materials, and is recommended in lieuof fractional crystallisation, is the adsorption of the radioactivesubstance by shaking the solution with metasilicic acid gel, preparedby the hydrolysis of dilute vapour of silicon tetrachloride andthe dialysis of the solution obtained.The silica is removed, afterfiltration and drying, by volat-ilisation with hydrofluoric acid.67The method is novel and contrary t o general experience, in thatthe silicic acid, separating on evaporation from solutions of radio-active minerals in acid, adsorb hardly any radioactive matter. Nospecial conditions are laid down for the operation of the method,and such a preferential adsorption of radioactive substancea. bysilica is very open to question.It is notable that of the ten radio-elements of longest period,only three, uranium, actinium, and polonium, have a distinctchemical nature different from that of any other known element,and in the case of the first the evidence t.hat it consists of a non-separable pair of elements differing in atomic weight by 4 unitshas been frequently alluded to.Thorium is chemically non-(ifj A. F. Kovarik, Physikal. Zeitsch., 1911, 12, 83; A . , ii, 173.Gi B. El~ler and A.I. Fellner, BLT., 1911, 44, 2332 ; A., ii, 957RADIOACTIVITY. 293separable from ionium, radiothorium, and uranium-X ; meso-thorium-1 is non-separable from radium, a statement which appliesalso to the two substances of shorter period, thorium-X andactinium-X ; radium-D or radio-lead is non-separable from lead.These statements are not a t all, as might be supposed, merelynegative expressions of failure due to the difficulties of investigation.The statement, for example, that mesothorium-1 is non-separablefrom radium completely describes the chemistry of that substanceso far as it is known, and indicates, for example, that it isdifferentiated most definitely from every one of the whole of therest of the common elements.I n addition, the three emanationsare chemically non-separable from the other members of the zerogroup of the Periodic Table. The other radioactive substancesknown are, with two or three exceptions, members of the threeactive deposit groups. The ease with which these groups areisolated, unmixed with inactive matter, from the volatile emanationspossibly accounts for the fact that none of them are known toresemble known elements. It must be remembered, however, thatthey represent in the Periodic System the transition, through thenon-valent emanations, from the electropositive elements, a t thebeginning of one period, to the eledronegative elements a t the endof the last period.Von Lerch’s well-known rule that the successivemembers of the active deposit groups become progressively moreI‘ noble ” in their electrochemical behaviour, a t least until the C-members are reached, is significant in showing that this transitionis not abrupt, but through a succession of well-defined, if veryunstable, forms. I n the periodic classification, the three VIIIthgroups occur only in the middle of the long periods, and not betweenthe ends of these periods (halogen elements) and the beginning ofthe next (argon gases). Hence the active deposit groups, which intlheir electrochemical behaviour resemble the noble metals, althoughthey would fall in the VIIIth group in the usual classification, arerelated to them very much, for example, as the elements, zinc,cadmium, and mercury, are related to the alkaline earth elements.The chemical nature of the radio-elements is thus becoming fairlycompletely known, in spite of the fact that in no field is moreentirely untrustworthy experimental work published.Uranium Minerals.To avoid the errors and the laborious operations of the solutionmethod of estimating minute quantities of radium in rocks andminerals, a fusion method has been devised.68 An electricallyheated platinum crucible is covered with a quartz bell jar made68 J.Joly, PhQ.Mag., 1911, [vi], 22, 134 ; A., ii, 685294 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.air-tight by standing in an annulus on the bed plate, filled withmercury, so that the gas expelled in the fusion of the mineral withfusion mixture or borax is collected and can be tested in theelectroscope after the fusion. The method is rapid, and gives, as arule, a much higher radium content than the solution method.With acidic rocks, the fusion is accompanied by vigorous &er-vescence, which assists the escape of emanation. The same resultmay be attained in the case of basic rocks if boric acid is added tothe mixture before fusion. Very small quantities of reagents arenecessary, and there is greater certainty against contaminationduring the determination than in the usual met'hod, which is opent o grave uncertainties owing to there never being a completeguarantee that some of the radium has not been precipitated outin the non-emanating condition.0QA number of papers have been published on the question whetherthe ratio of radium to uranium in minerals is a completely constantquantity, even when palpable exceptions, such as autunite, areexcluded.It will be recalled that one investigation in which theradium was separated chemically, prior to estimation by theemanation method, indicated that the older the mineral, the higherwas the radium ratioloI n the continuation of this work twenty-one minerals wereexamined which, on the whole, bore out the former conclusion.The ratio was highest for minerals from Cornwall, and for Cornishpitchblende exceeded that for the Joachimsthal pitchblende byabout 20 per cent.71 In another research confined principally t o anexamination of the ratio in pitchblendes and thorianites, similarvariations were observed for certain specimens, but the specimensleast liable to have been contaminated with radium beforeexamination gave a ratio constant within the limits of error.72 I na further research, in which the minerals were dissolved in hotconcentrated sulphuric acid to liberate the emanation, the ratiofor thorianite and East African pitchblende was the same as forJoachimsthal pitchblende within the limit of error.73 The lowratio for the autunite was accounted for by the loose formation ofthe mineral and the action of percolating water.The 8ameexplanation was held t o cover the absence of helium and lead. Adetermination of the ionium-radium ratio in the minerals showed69 A. S. Eve and D. BTcIntosh, Trans. Boy. Soc., Canada, 1910, [iii], 4, 111, 67 jA., ii, 841.70 Ann. Report, 1909, 260.72 R. Pirret and F. Soddy, Phil. Mag., 1911, [viJ, 21, 652 ; A . , ii, 454.73 W. Marckwald and A. S. Russell, Ber., 1911, 44, 771 ; Jnhrb. Xadioaktiv.Mlle. E. Gleditsch, Le Radium, 1911, 8, 256 ; A . , ii, 845.Elektronik, 1911, 8, 457 ; A . , ii, 360RADIOACTIVITY. 295that the ratio for autunite and carnotite, although somewhat lowerthan for Joachimsthal pitchblende, is sufficiently near the normalto disprove views advanced previously with regard to theseminerals.74 The question is in rather an unsettled state.Theaction of percolating water in removing radium from autunite bedsis known from the case of the radiferous pyromorphite of the Issy1’Eveque district.75 It is, however, discult to believe that theaction of percolating water can have anything to do with theabsence of lead, helium, and the variability of the radium ratio inthe massive, almost perfect, unweathered crystals of autuniteencountered in the Portuguese deposits, or that this material hasmore than a transitional existence in geological time. Probablyrecrystallisation of the material is in actual active operation at thepresent day, it being dissolved out by water charged with carbondioxide in one place and deposited in another.That these compactcrystals have been in existence indefinitely, and that the lead, forexample, as formed throughout the mass of the crystal, is removedby percolating water leaving the crystal undissolved and evenunweathered, is more difficult to suppose than that the mineralitself is being continually dissolved and redeposited. With regardto the whole question, leaving out of account all disturbingelements, there remains some doubt as to the absolute constancyof the uranium-radium ratio in minerals, regardless of their age,as the disintegration theory, in its present form, requires, butwhether the variations observed have a theoretical significance isstill an open question.The determination of geological age from the uranium-lead ratiohas been carried out for a series of thorite-bearing nepheline-syenites, probably of lower Devonian age, found in the Christianiadistrict.The district-a depressed area of 4000 square milea-waschosen because of its isolation from the surrounding rocks by faultson every side. The minerals examined-thorite, zircon> apatite,and sphene-contain much larger proportions of uranium than thesurrounding magma, so that the segregation of the mineral fromthe magma furnishes a definite starting point from which theaccumulation of disintegration products commences. The ratio oflead to uranium in 15 of these minerals was tolerably constant,increasing somewhat from 0.041 to 0.068 as the quantity of uraniumdecreased. Possibly this increase is due to the initial presence ofsome lead in the minerals.The results show a ratio sufficientlynear constancy to be very striking. From the mean value the ageof the formation was deduced to be 370 million years.7674 Ann. Xcport, 1910, 263.7% A . Holmeg, I’roc. Roy. h’oc., 1911, A, 85, 245 ; A . , ii, 570.i5 Ibitd., 1909, 260296 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The Radium Series.Badium-A new determination of the atomic weight of radium,in which a gram of radium chloride was available, gave the number225.95 (Ag=107*88, CI=35.457), which is nearly half a unit lowerthan the accepted value. After this atomic weight had beenreached, 50 crystallisations of the hydrochloric acid solution, and13 precipitations with alcohol, caused no further change in theatomic weight.The chloride was melted in hydrogen chloridebefore weighing. I n one series the chloride was precipitated assilver chloride and weighed, the amount of silver chloride in thewashings being estimated by the nephelometer. I n another seriesthe amount of silver necessary for the complete precipitation of thechlorine in a weighed amount of the chloride was found.77A new determinat'ion of the arc and spark spectra of radiumconfirms, for the most part, previous determinations. I n bothspectra two of the radium lines, namely, 3814.6 and 4682.4, werevisible in a preparation containing only 0.001 per cent. of radium.The line 5017.9 was ascribed to barium, and 6439.1 to calcium. Inthe weaker preparations lines due to scandium and yttriumwere observed, and in the spark spectrum an unidentified line,3993.25, was seen, strongest in the weakest preparation, and fadingas fractionation proceeded.73From a consideration of a large number of the properties, suchas heat of solution and formation of the halogen salts, sulphates,selenatea, hydrides, and carbides, so far as they are known, theaffinity of oxides for oxygen, the solubility of the fluorides,hydroxides, and carbonates of the metals of the alkali and alkaline-earth families, these elements were found to form a regular series,in which the properties augment or diminish regularly in theorder : calcium, lithium, strontium, barium, sodium, potassium,rubidil;m, msium. I n this series radium enters between bariumand sodium, and many of its physical and chemical constan&, stillundetermined, have been calculated from this a.nal0gy.7~Radium Enianathn.-Two careful series of measurements of thesolubility of radium emanation in various liquids a t various tem-peratures have been caried out, in which, after t'he gas and liquidphases have come into equilibrium, they have been separated andleft four hours, after which time the y-radiation furnishes a con-venient maasure of the amount of emanation secured by each77 0.Honigschmid, K. Akad. Wiv. V'i'e?~ , Sitzung., 19th Oct., 1911.78 F. Exner and E. II~~cheli, Sitzungsbw. K. Aknd. lPiss. IVicn, June, 1911,59 HI. de Forcrand, Comnpt. rend., 1911, 152, 66 ; A., ii, 172.120, IIaRA DlOACTIVlTY.297phase.80 The solubility in water is given as 0.51 a t Oo, 0’39 at go,0.303 at 1 4 O , 0.285 a t 18O, and 0.153 a t 40°. The temperature-coefficient is thus very important. Glycerol (0.21 at 18.) is theonly liquid found dissolving less emanation than water, the otherorganic liquids all absorbing much more strongly than water.Carbon disulphide absorbs 80 times, and aniline 13 times more thanwater, the other solubilities determined being intermediate.Henry’s law was obeyed exactly, which is of interest in view ofthe excessively minute partial pressures involved. The volatilisationtemperature of radium emanation has also been re-investigated bya new method.8lDiscussion has taken place with regard to the origin of thecarbon dioxide from thosrium solutlions submitted to the action ofradium e”manation.s2 Thorium nitrate, specially purified to avoidas far as possible organic impurities, and which gave carbon dioxideunder the action of the emanation, gave i t also when treated withpotassium permanganate.On the other hand, iLn account of themethods employed in the preparation of the thorium nitrate usedin the original experiments and the precautions taken to securecontamination from carbon has been published, but so far no actualanalysis of this thorium preparation for carbon has been recorded.Radium-D.-A novel but unsuccessful attempt has been madeto put into evidence the metallic nature of radium-D by depositingi t from the radium emanation in a capillary tube of very smallvolume prlsvided with two electrodes and measuring the resistancebetween the electrodes as the change of the emanation occurred.83Attempts were made to make good contact between the platinumelectrodes and the tube by silvering the tube except over the areabetween the electrodes, but the silvering became transparent underthe action of the emanation.Traces of deposits of brilliantlymetallic lustre by reflected light were observed in some of theexperiments, as in similar ones by other observers. The deposits,however did not form uniformly, but in restricted areas, and theresistance of the tube in all cases remained above a megohm as wheninitially prepared. They also disappeared like the silver depositsin the course of time.The Thorium Series.Mesothoriunt-1 .-Technically prepared mesothorium is obtainedfrom monazite sand containing about 0.3 per cent.of uranium andEo E. Itamstedt, Le Kndiwn, 1911, 8, 253 ; A., ii, 842. Ii. W. Boyle, Phil.M a g , 1911, [vi], 22, 840 ; A . , 1912, ii, 10.R. W. Koyle, Phil. ilin!/., 1911, [vi], 21, 722 ; A , , ii, 569.11. Herschfnltrl, Cmq& 1c77(2., 1911, 153, 255 ; Le lintliwn, 1911, 8, 417 ;A . ii, 843. Sir W. Itaiiisay, C‘oiizpl. reiLd., 1911, 153, 373 ; if., ii, 843.8R I,. liolowrat, Le 12adiu?n, 1911, 8, 401298 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.4 to 5 per cent. of thorium oxide, and of its penetrating rays 75 percent. are due to mesothorium, and 25 per cent. to radium. Themaximum of activity, due to the regeneration of radiothorium, isreached in 3.2 years.It may be fractionated until its penetratingrays are initially about four times as intense as those from pureradium salts, and from the ratio of the periods of the two sub-stances it is then estimated to contain 1 per cent. by weight ofmesothorium and 99 per cent. of radium.84 Thus the determinationof the spectrum, for example, of mesothorium seems to be bound upwith the possibility of finding a thorium mineral sufficiently freefrom radium. Some monazite sands appear to contain far lessuranium than that given above, so that the problem may be capableof s o h ti on .*5Radiothoriwm.-The half-period assigned to this member is twoyears, but some recent measurements have put a much lower value-a few months only-on the period.86 This is, however, contraryto the general experience of those who have measured the decay ofthe activity of technical preparations directly.Thorium Emanation.-The molecular weight of the thoriumemanation, determined by a modification of Bunsen’s effusionmethod,*7 gave a result in the neighbourhood of 200, the extremevalues being 210 and 194.Part of the uncertainty arises from theperiod of the emanation not being very exactly known, any errorin the period introducing a five-fold greater error into the calculationof the molecular weight.88Chemical Actions of the Rays of Radium.The decomposition of hydrogen peroxide by the rays of radiumhas been much studied.89 The natural rate of decomposition isincreased both in paraffined and not paraffined vessels, and thereis in some cases an after-working, due probably to the decompositionof the glass by the rays and the production of new substancescapable of producing catalytic action.The rate of decompositionincreases with rise of temperature, very much the same a6 inphotochemical reactions, and much less rapidly than the rate of theunassisted decomposition.84 0. Hahn, Chem. Zeit., 1911, 35, 845; A . , ii, 845.85 Coinparo Haitinger and Peters, ,%tzicngsber. K. Akad. Wiss. Wien, July, 1911,86 Miss M. S. I,eslie, Le Rndiz6m, 1911, 8, 356 ; A . , ii, 1048.87 Compare Ann. Xeport, 1910, 278.88 Miss M. S. Leslie, Comnpt. rend., 1911, 153, 328 ; A , , ii, 843.89 I<. yon Kzrosy, Pfiiigcr’s Archiv, 1910, 137, 123 ; A . , ii, 9.A. Kailan,120, IIa.Monatsh., 1911, 32, 1019; A , 1912, ii, 10RADIOACTIVlTY. 299The volume changes of ammonia under the action of the raysfrom an uncovered radium salt have been studied.90 After iw1initial contraction for five weeks, which is ascribed to the presenceof air, steady expansion occurred for a year. With the apparatusfilled with undried air, a regular contraction occurred, which wenton for four months, whilst with dry nitrogen a similar contractionfor one month took place. The decomposition of water by thea- and &rays of radium has been re-investigated.91 The &raysfrom 1 curie of emanation give 6.486 C.C. of mixed gas duringcomplete change, whereas when the emanation is dissolved in water,so that there is only the liquid phase present, 136.66 C.C.result.The chemical action is ascribed t o the charges on the rayp ratherthan to mechanical consequences of the collisions between themolecules and the radiant particles.Radium bromide, sealed up with perfectly dry hydrogen andoxygen, causes no combination, but the ionisation of ordinary airby the rays of radium is not affected by perfect drying. Radiumbromide brings about the complete mutual decomposition ofhydrogen sulphide and sulphur dioxide in a few hours, the wholeof the water and sulphur formed condensing on the radium salt.It has been suggested that the power of the ions to condense liquidwater drops, in which the chemical action occurs, may explain theinfluence of moisture on chemical change.For it was found that10 milligrams of radium bromide, exposed a t the ordinary tempera-ture for two days to an atmosphere saturated a t Oo, collected 1.5milligrams of liquid water.92 That this is an effect of ions apart fromthe lowering of the vapour pressure by the dissolved salt was not,however, proved. The colours produced in various minerals andother substances by comparatively large quantities of radium havealso been investigated.93It seems worth while calling attention here to one point inregard to the chemical action of the ray6 of radium on air whichseems to have been overlooked, and which forced itself on theattention of the writer many years ago. Nitrous oxide is producedin comparatively large quantity, for example, if air containingemanation is stored over mercury.For this reason it is impossibleto obtain the emanation pure by condensation with liquid air, ifpreviously, as, for example, by leakage, it has become mixed withair. As the emanation rapidly destroys the lubrication of stopcocks,the only way t o avoid leakage is by the use of a mercury sealbetween the radium solution and the pump. Quite frequently, in'" E. P. perman, 15rans., 1911, 99, 132.!'I F. L. Usher, Jnkrb. Radionktiv. Elelctronik., 1911, 8, 323 ; A., 1912, ii, 6.':j C. Doelter and H. Sirk, Nonatsh., 1910, 31, 1057 ; A., ii, 171.H. B. Baker, Royal Institution L~cturu, delivered March 11, 1911 ; A . , ii, 244300 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.reading the literature, unrecognised examples of this formation ofnitrous oxide from air are met with, so that attention may bedirected to it. No doubt the radium emanation in the air is oneof the agents in the formation of combined nitrogen, heretoforeattributed t>o electrical discharges.Radioactivity of the Earth and Atmosphere.The papers in this section, which are very numerous, can onlybe briefly referred to. An extensive survey of the Leinster granite,which covers an area of 600 square miles, showed a mean contentof radium of 1.7 x 10-12 gram, and of thorium of 7.1 x 10-6 gram,per gram of rock. On the whole, the proportion between the twoelements was wonderfully uniform, but the three samples richest inradium did not contain thorium.94 Some rocks from the Antarcticregion of S. Victorialand were very similar in their content ofradium and thorium to those just described.95 Something of thenature of a constant ratio, about 2x10-7, between the elementsseems, as a rule, t o occur. Except for the granites, which haveusually a high radium content, and of which a disproportionatenumber have been investigated, the mean content of radium insedimentary as well as igneous rocks appears similar, at about1-4 x 10-12 gram per gram.g6 An investigation of the a- and&activity of rocks has given results not always in agreement withdeterminations by the emanation method, as though other unrecog-nised radio-elements than radium and thorium might beWith regard t o the amount of radium emanation in the air it isnotable that in the middle of the Atlantic Ocean the quantity doesnot appear to be greatly different from that near the ~ 0 a ~ t . 9 8 Severalseries of experiments have been done on the escape of emanationfrom the soil into the air.99 It has been established that a veryrapid escape of emanation occurs, much influenced by the hygro-metric condition of the soil and by the fluctuations of the barometer,and that this is probably the only source of the emanation foundin the air. The amount of radium emanation in the air drawn upfrom underground is many thousand times greater than that present94 A. L. Fletcher, Phil. Mag., 1911, [vi], 20, 102 ; A., ii, 89.95 A. T,. Fletcher, ibid., 21, 770 ; A., ii, 570.96 E. H. Biichner, Proc. X. Akad. Wetensch., An&wdanz, 1911, 13, 818 ; A , , ii,97 A. Gockel, Jahrb. Radioaktiv. Elcktronik., 1910, 7, 487 ; A . , ii, 174.98 C. Runge, Nachr. K. Ges. Wiss. Gottingen, Math.-yhysikal. Klasse, 1911, 99 ;A., ii, 1050 ; A. 5. Eve, Phil. Mag., 1911, [vi], 21, 26 ; A . , ii, 89.99 J. t'. Sanderson, Amer. J. Sci., 1911, [iv], 32, 169 ; A . , ii, 846 ; J. Joly andL. B. Smyth, Sci. Proc. Roy. DubZ. Soc., 1911, 13, 148 ; A., ii, 1048 ; J. Satterly,Proc. Camb. PM. Soc., 1911, 16, 336.243RADIOACTIVITP. 301in the atmosphere. A mean value of 80x10-l2 curie per cubicmetre of bhe atmosphere has been deduced. Less found a t Tokyoby indirect methods may be capable of another exp1anation.l Withregard to the penetrating rays from the earth, although the opinionthat this is accounted for by the known amounts of radioactivematter in the earth’s crust is the prevalent one, the opinion hasalso been expressed that part is independent of this origin andpersists over the surface of the sea, and that this part is subjectto notable rapid oscillations in magnitude.* The absorption of thesepenetrating rays by the air should be easily detectable even a t analtitude of only 100 metres, whilst at an altitude of 1000 metrestheir effect should be negligible.3 Some experiments from the ClockTower of the Toronto City Hall, 64 metres high, bear out thesec alculations.4F. SODDY.S. Kinoshita, S. Nishikawa, and S. Ono, Phil. Mag., 1911, [vi], 22, 821 ; A . ,1912, ii, 12.a D. Pacini, Le Radium, 1911, 8, 307.A. S. Eve, Phil. Mag., 1911, [vi], 21, 26; A . , ii, 89.J. C. McLennan and E. N. Macallum, ibid., 22, 639 ; A., ii, 960

ISSN:0365-6217    

DOI:10.1039/AR9110800269

出版商:RSC    

年代:1911

数据来源: RSC

摘要:

INDEX OH AUTHORS’ NAMES.Abderhalden, E., 179, 190, 195.Ackerrnann, D., 186.Adams, L. H., 160.Adhiciiry, B. B., 27.Adlam, G. H. J., 34, 244.Adler, O., 118, 121.Adler, R., 118, 121.Aldridge, M., 99.Alexander P., 176.Allen, E. !I?., 159, 160.Amberg, S., 205.Ampt, J. A., 219.Ancel, P., 194.And&, E., 88.And&, G., 230.Andrews, A. E., 175.Antonoff, G. N., 289.Applebey, M. P., 2.Ark, H., 103.Armsby, H. P., 236.Armstrong, E. F., 228.Armstrong, H. E., 13, 14, 30, 228.Aron, H., 212.Arschinow, W. W., 257.Asahima, Y., 149.Atack, F. W., 166.Atkins, W. R. G., 173.Austin, P. C., 91.Auwera, K., 51, 52.Auzies, J. A. A., 169.Averbeck, H., 100, 101.3achran F., 158.3acklunh, H., 161.3aeyer, 0. von, 278, 279.3ain, 188.3aker, H.B., 24, 27, 34, 244, 299.3al1, W. C., 158.3aly, E. C. C., 53.3ang, I., 189.3arbier, P., 258.Bardach, B., 169.Barger, G., 143, 144, 187, 188.Barker, B. T. P., 234.Barker, T. V., 38, 246.Barnett, E. lde B., 90.Barratt, T., 274, 282, 289.Barrett, W. H., 154.Barrow, F., 65.Barrowcliff, M., 121.Baskerville, C., 156.Battelli, F., 187.Bauer, E., 247.Baumhauer, H., 246.Baxter, G. P., 2, 19, 266.Bayliss, W. M., 11.Beck, R., 267.Becke, F., 247.a h a l , A., 99.Benda, L., 118, 119, 121, 126, 127, 128.Benedek, L., 262.Benedicks, C., 266.Beneker, J. C., 163.Benner, R. C., 168.Berkeley, Earl of, 2.Berlin, E., 195.Berry, A. J., 36.Bertheim, A., 117, 118, 120, 122, 123,Berthelot, D., 111.Bertrand, G., 117.Besson, A., 43.Beutell, A., 258, 260.Bierry, H., 113.Biilmann, E., 55.Biltz, W., 12.Black, J.W., 175.Bloch, I., 132.Bloch, L., 32.Blumenthal, H., 45.Boeke, H. E., 263.Bolton, E. R., 174.124, 125, 126, In.REP.-VOL. VIII. 305 306 lNDEX OF AUTHORS’ NAMES.Boltwood, B. R., 276. 277.Bonillas, Y. S., 257.Botta, W., 242.Bouin, P., 194.Bousfield, W. E., 1.Bousfield, W. It., 1, 154.Bowman, H. L., 267.Boyle, R. W., 297.Boynton, C. N., 164.Bradley, H. C., 196, 197.Bradley, W. M., 260.Braun, J. von, 87, 89.Breteau, P., 91.Broek, A. van der, 271.Brouwer, H. A., 250.Browne, A. W., 42.Brune, R., 134.Bruner, L., 19, 87, 112.Buchner, E. H., 300.Bugge, G., 132.Bumstead, H. A., 281.Burgess, L. L., 2.Burgess, M.J., 33.Burton, R. C., 259.Butler, B. S., 248, 262, 264.Butureanu, V. C., 259.Caccia, P., 123.Cain, J. R., 166.Cameron, F. K., 247.Campbell, N., 281.Canfield, F. A., 265.Caro, N., 177.Carson, C. M., 21.Cesaris, M., 117.Challenger, I?., 76.Chapman, D. L., 28, 41.Chattaway, 3’. D., 99, 246.Chauvenet, E., 47.Chick, Miss H., 190.Chieffi, G., 110.Chouchak, D., 230.Christensen, H. R., 217.Ciamician, G. L., 106, 110.Clarke, H. E., 267.Clarke, H. T., 52.Claude, G., 47.Clayton, A., 53.Clo, J. H., 283.Clou h, G. W., 64.Cock\urn, T., 175.Cohen, E., 22.Cohn R., 180.Collek, E., 167.Cook, C. W., 261.Cooke. W. T.. 43.Coopei, H. C.‘, 247.Cotty, A., 2.Crymble, C. R., 52, 53.Curie. Mme. M.. 290.Curtel, G., 174.’Curtman, L.J., 158.Czarnecki, S., 19, 112.Dale, H. H., 143, 186, 188.Daniel, K. C. R., 171.Danysz, J., 279.Darzens, G., 87.Daudt, H. W., 2.Dawson, H. M., 103.Day, A. L., 239.Degrazia, J. von, 175.Dehn, W. M., 123.Delkpine, M., 133.Iletoeuf, A., 99.Dewar, Sir J., 24, 44.Dey, B. B., 161.Dieckmann, T., 167.Dief enthaler, O., 165.Diesel, W., 247.Diethelm, B., 167.Dimroth, O., 103.Dinslage, E., 178.Dittler, E., 240.Dittrich, M., 165.Diuon, H. B., 31.Dobbie, J. J., 97, 140.Doelter, C., 40, 299.Doerinckel, F., 241.Dojarenko, A. G., 219.Donau, J., 155.Donnan, F. G., 12.DorBe, C., 195.Duane, W., 283.DucIaux, J., 13.Diirrfeld, V., 258.Dunstan, W. R., 29.Duparc, L., 254, 262, 263.Eakle, A.S., 251, 259.Ebler, E., 157, 292.Eckardt, M., 167.Edwards, Miss M. G., 172.Ehrlich, P., 117, 118, 120, 122, 123,Einbeck, H., 141.Eisenlohr, P., 50, 51.Embden, G., 193.Emde, H., 175.Emmerich, R., 220.Endell, K., 240.Ephraim, F., 42.Esch, W., 176.Euler, H. von, 185.Eve, A. S., 283, 294, 300, 8301.Everest, A. E., 73.Ewins, A. J., 144, 180.Exner, F., 296.Eyre, J. V., 14.Fabinyi, R., 170Fajans, K., 285, 28i.124INDEX OF AUTHORS’ NAMES. 307Farbenfabriken vorm. F. Baver & Co., -88, 106.Farrington, 0. C., 265, 267, 268.Feder, E., 174.Feit, -W.,- 161.Feld, W., 167.Fellner, M., 292.Fine, M. S., 187.Firth, J. B., 39, 155.Fischer, E., 60, 62, 63, 64, 65, 116, 117,Fischer, F., 36, 44, 48, 168.Fitzgerald, Miss M.P., 191.Fletcher, A. L., 300.Fletcher, H., 283.Flint, W. R., 24.Foch, A., 274.Fokin, S., 93.Foote, H. W., 260.Forcrand, R. de, 296.Ford, W. E., 259, 264.Foreman, F. W., 236.Forli-Forti, G., 110.Fouard, E., 10.Fournier, L., 43.Fox, J. J., 97.Franck, J., 283.Frank, F., 192.Franke, A., 113.Frankel, E., 158.Frankland, P. F., 53.Franklin, E. C., 15.Fraser, H., 212.Freudenberg, K., 171.Freund, M., 90, 142.Friend, J. A. N., 29, 31.Fries, K., 131, 136.Froboese, V., 48.Fuller, T. S., 247.Funk, C., 213.Gams, A., 138, 139.Gutaldi, C., 251, 258.Gates, C. B., 38.Gaubert, P., 243.Gaudechon, H., 111.Gauge, A. J. H., 97Gautier, A., 254Gee, F. H,, 41.Geiger, H., 274, 282, 284.Gemmell, A., 258.Gerhart, H., 243.Getman, F, H., 51.Giglioli, I., 228.Gilbert, A..162.171.Gimingham; C. T., 225, 234.Girard, P., 11.Glahn, W., 134.Gleditsch. Mlle. E.. 294.Glendinning, 52. ’Glinka, N., 92, 93.Glover, W. H., 14.Gockel, A, 300.Godden, W., 182.Goldmg, J., 224.Golla, F., 195.Gooch, F. A., 164.Goodey, T., 224.Gorter, K., 143.Gottlob, K., 109.Goy, 179.Gray, J. A., 280.Green, W. H., 219.Grignard, V., 90.Groh, R., 64.Grosspietsch, O., 249.Gunther, A., 129.Guichard, M., 41.Guild, 3’. N., 256.Hahn, O., 278, 279, 298.Hall, A. D., 215, 232, 235.Hamill, J. M., 209.Hammarsten, O., 189.Hantzsch, A., 55, 57, 58, 59, 102.Harcourt, A. G. V., 24.Harries, C. D., 91, 108, 109.Harris, A. B., 12.Hartley, H., 154.Hartmann, L.M., 168.Hartmann, w., 174.Harvey, W. H., 188.Haschek, E., 296.Hauser, F., 281.Hauser, O., 255.Headden, W. P., 222.Heath, G. L., 162, 168.Hedin, S. G., 189.Hehner, O., 177.Helferich, B., 117.Henderson, Y., 186.Henri, V., 11, 113.Henze, M., 197.Hepner, A., 173.Herschfinkel, R., 297.Hervey, W. H., 233.Herzfeld, H., 255.Hem, F. L., 264.Hess, K., 150.Hess, V. B., 281.Hibbert, Miss E., 167, 171.Hibbert, H., 170.Hicks, W. B., 165.Higgins,‘S. H., 46.Hilditch, T. P., 52, 53, 131, 132, 135,Hill, J. R., 29.Hinrichsen, F. W., 167, 169.Hocson, I?., 212.Hohn, F., 132.Honigschmid, O., 23, 296.Hoesslin, H. von, 192.136.x 308 INDEX OF AUTHORS’ NAMES.Holdcroft, A. n., 259.Holmes, A., 295.Holt, A., 40, 43.Holtz, H.C., 262.Hope, E., 137.Hopkins, F. G., 207, 235.Horn, F. R. van, 261.Horn van den Bos, J. L. M. van der,Houstoun, R. A., 16.Hudson, C. S., 114.Hiini, E., 151.Hiittner, C., 164.Humphries, H. B. P., 64.Hutchin, H. W., 167.Hutchinson, H. B., 220, 231.Hynd, A., 116.Inghilleri, G., 113, 226.Tpatieff, W. N., 37, 92, 94, 95, 107.Trvine, J. C., 116.Isler, M., 147.Twanoff, W. N., la.?Jacobs, W. A., 115, 200.Jaeger, F. M., 241, 246.Jannasch, P., 157.Janneret, B., 44.Jellinek, K., 45.Jefek, B., 267.Jorg, P., 135.Johnston, A. A., 250.Johnston, J., 159, 160.Jolibois, P., 22.Joly, J., 293, 300.Jones, H. C., 18.Jones, H. E., 28.,Jones, H. O., 24, 53, 132.Jones, W., 203, 204, 205.Jones, W. J., 87.Jong, A.W. K. de, 106.Joyner, R. A., 35.Juschtschenko, A. J., 202.Kahn, R., 118, 119, 121.Kailan, A., 298.Kajiura, S., 211.Kameler. H.. 47.164.Kaiielmeier, ‘P., 101, 104, 141.Kappen, H., 177, 178.Ksssner. G.. 42.Kastle, J. H., 172.Katzer, F., 251.Kaufmann, A., 140, 142.Kazanecky, P., 39.Keiser, E. H., 97.Kempf, J., 134.Kempf, R., 155.Kenyon, J., 54.Kertess, E., 193.King, H., 88.Kinoshita, S., 301.Kippiiig, B. S., 76.Klason, P., 176.Klein, A. A., 247.Klein, D., 27.Klever, H. W., 109.Klinger, H., 111.Klooster, H. S. van, 240.Knecht, E., 166, 167, 172.Kneip, A., 175.Knoffler. G.. 141.Knoop, F., 193.Knorr, L., 100, 101, 102, 104, 142, 150!172.Knorre, G. v., 163, 167.Kober, P. A., 179.Koch, A., 221.Konig, J., 219.Koenig, P., 158, 163.Korosy, K.von, 298.Kohler, R., 188.Kolb, R., 244, 263.Kolowrat, L., 297.Korneck, O., 176.Kovarik, A. F., 282, 292.Krauskopf, F. C., 5, 9.Krauz, C., 115.Krdlikowski, M., 19, 112.Kruyt, H. R., 56.Kiimmell, G., 46.Kullberg, S., 185.Kunz, G., 251.Kurtenacker, A., 169.Kusnetzoff, S. D., 254, 262.Lacroix, A., 254, 255, 257.Lahociiiski, Z., 19, 87, 112.Laidlaw, P. P., 186, 188.Lambert, B., 29.Lanfry, M., 90.Lange, H., 257, 277.Lankshear, F. R., 53.Lapworth, A., 53.Larsen, E. S., jun., 250.Larsen, 0. H., 217.Laschtschenko, P. N., 244.Lathrop, E. C., 217.Lauder, A., 140.Law, D. J., 169.Laws, E. G., 22, 98.Lebedeff, A. J., 224.Lebedeff, P., 241.Lebedeff, S. V., 91, 107.Lederer, K., 142.Leeuw, H.L. de, 21.TJemmermann, O., 217.Lenz, W., 158.Leslie, Miss M. S., 298.Lesser, E. J., 192.Levene, P. A., 115, 200, 203, 204.Lewis, G. N., 21INDEX OF AULiebermann, C., 89, 106.Lichtenstadt, L., 76.Lincio, G., 256.Llord y Gamboa, R., 254.Loczka, J., 262.Loewen, H., 141.Lohmann, A., 195.London, E. S., 185, 192, 202.Loram, H. Y., 162.Low, W. H., 162.Luhrig, H., 174.JI’Cabe, C. R., 166.Nacallum, E. N., 301.AlcCaughey, W. J., 247.McDermott, F. A, 180.McGrath, S. J., 123.Machiedo, L., 164.McIntosh, D., 294.McKenziq, A., 64, 65.McLennan, J. C., 301.Rlacleod, A. L., 107.McMaster, L., 97.McMillan, A., 137, 138.RlcNicoll, D., 116.Madelung, W., 161.Mailhe, A., 93, 94, 95.hlalaquin, P., 44.Mameli, E., 125.Manasse, E., 255.Marc, R., 243.Marckwald, W., 294.hlarr, F.S., 220.Marrs, L. E., 163.RIarschall, O., 143.Marsden, E., 274, 282, 289.Rfarsden, Miss E. G., 131.Marsh, J. E., 73, 95.Marshall, F. H. A., 194.Alartin, C. J., 190.Massol, L., 113.Mathews, J. H., 10.Mathewson, W. E., 170.Matsui, M., 133.Aiatthes, F., 242.Mauthner, F., 117.May, P., 130.NazB, P., 229, 230.Medigreceanu, F., 203, 204.Meisenheimer, J., 75, 76.Meitner, L., 278, n 9 , 283, 291.Mellor, J. W., 259.Mendel, L. B., 198.Menge, G. A., 154.Menge, O., 242.Menzies, A. W. C., 3, 4, 5, 6, 7, 0.Mercer, W. B., 232.Merczyng, H., 2.Rlerres, E., 177.Luff, B. D. W., 76.rJutz, o., 60.10RS’ NAMES. 309Merrill, G.P., 267.Metzger, I?. J., 163.Meunier, S., 267.Meyer, E. W., 151.Meyer, F., 23.Meyer, K. H., 101, 102, 104.Meyer, R. J., 164, 261.hfichaelis, A., 120, 129.Micklethwait, Miss F. M. G., 98, 123,Milarch, E., 142.Miller, N. H. J., 231, 233.Millikan, R. A., 283.Mitscherlich, E. A., 177.Monier-Williams, G. W., 209.Monnier, R., 177, 178.Moody, G. T., 29.Moore, B., 12.Mooser, W., 180.Moreau, E., 174.MoressBe, G., 253.Morgan, G. T., 53, 98, 123, 129, 130.Morgen, A., 235.Morozewicz, J., 250.Morse, H. N., 9.Moseley, H. G. J., 285.Moser, L., 157, 164.Miiller, E., 165, 167.Miiller, F., 195.Rluller, J. A., 162.Murmann, E., 163.Muttelet, E’., 174.Myers, J. E., 39, 43, 155.Nylius, F., 164.Nacken, R., 242.Neogi, P., 27.Neubauer, C., 240.Neubauer, O., 193.Ney, N., 175.Nicholson, J.W., 269.Nierenstein, M., 171, 236.Nishi, Af., 175.Nishikawa, S., 301.Nockmann, E., 173.Nordenskjold, I., 257.Nuttall, J. M., 274.Oddo, B., 171.Oddo, G., 117.O’Donoghue, C. H., 194.Olie, J., jun., 22.Ono, S., 301.OppB, A., 145.Orton, K. J. P., 87, 88, 136, 172.Oshorne, W. A., 197.O’Sullivan, H. H., 53.Owen, 185.Pacini, D., 301.Padua e Castro, J. M. de, 252.129, 130310 INDEX OF AUTHORS' NAMES.Palache, C., 253, 261, 263.Palozzi, A., 199.Pamfil, G. P., 157.Panichi, U., 253.Parkin. J.. 226.Partington, J . R., 33.Pascal, P., 54.Paterrib, E., 110.Patta, A., 123.Patterson, T. S., 53.Pavy, F. W., 182.Pellini, G., 255.Perkin, W.H., jun., 71, 73, 137, 140.Perman, E. P., 299.Petterd W. F., 248, 252.Pfeiffer: P., 70.Philippe, L. H., 116.Piccinini, G. M., 196.Pickard, R. H., 54.Pictet, A., 138, 139, 140.Pigoulowsky, G., 133.Pilch, F., 155.Piloty, O., 150.Piolti, G., 248.Piotrowski, H., 42.Pirret, Miss R., 294.Piutti, A,, 277.Plummer, G. W., 260, 262.Pochettino, A., 45.Poschl, V., 262.Pope, W. J., 71, 73,Popielski, L., 195.Potter, M. C., 225.Pouget, I., 230.Prescott, W. G., 131.Pribram, R., 113.Prileschaheff, N., 90.Pringsheim, H., 223.Prior, G. T., 249, 263, 264.Priwoznik, E., 256.Pschorr, R., 141.Pozzi-Escot, M. E., 158.Purvis, J. E., 53, 132.Pyman, F. L., 119, 121, 143, 144.Quercigh, E., 255.Rabe, P., 137, 138, 142, 143.Rabinowitsch, A.G., 192.Raikow, P. N., 163.Ramsay, Sir W., 297.Ramstedt, E., 297.Ranc, A., 113.Randall, M., 21.Rankin, G. A., 239.Raske, K., 63.Rather, J. B., 177.Rauw, H. de, 255.Rawson, C., 164.Rsy, P. C., 42.Beimer, M., 106.Roimers, F., 175.Reinthaler, F., 162.Iiemfry, F. G. P., 121.Remy, T., 221, 233.Rengade, E., 254.Rennie, E. H., 43.Rettberg, H., 141.Reuss, F., 56.Revis, C., 174.Revutsky, Mlle. E., 258.Reynolds, W. C., 119.Richards, T. W., 23, 34.Richmond, H. D., 173.Richter, E., 158.Richter, M. M., 133.Rieke, R., 240.Ries, A., 245.Riesenfeld, E. H., 28.Ringer, W. E., 188.Rinne, F., 244, 263.Ritter, H., 91, 92.Ritzel, A., 243.Roaf, H. E., 12.Robinson, C. S., 218.Robinson, R., 137.Roche, D.A., 157.Roerdansz, W., 111.Rosing, G., 221.Rogers, A. F., 256.Romburgh, P. van, 144.Rme, W. C., 198.Rosenheim, O., 188.Rosenstiehl, A., 35.ROSS, W. H., 168.Roth, P., 142.Rothe, O., 100, 101.Riicker, C., 107.Ruhemann, S., 179.Runge, C., 300.Rupp, E., 162.Russell, A. S., 294.Russell, E. J., 215, 224.Rutherford, E., 272, 276, 277, 284.Sabot, R., 254, 263.Sackett, W. G., 223.Sabatier, P., 91, 92, 93, 94.3aint-Sernin7 A., 181.Salway, A. H., 137.sand, H. J. S., 168, 169.Sanderson, J. C., NO.Sandonnini, C., 241, 242.3atterly, J., 300.kandola, E., 42.Schaller, W. T., 248, 249, 250, 253,kheibIer, H., 63, 64, 65.Schetelia. J.. 252.254, 259, 260, 261, 262, 264, 265.Ichitten%elm', A., 192, 202.Schmidt, H., 179.khmitz, E., 193INDEX OF AUTHORS' NAMES.311Schoeller, W., 63.Scholz, A., 174.Schoorl, N., 158.Schreiner, O., 217.Schroder, J., 174, 175.Schubert, H., 102, 172.Schulten A. de, 247.Seeker, 8. F., 170.Seidel, T., 157.Sen, H. K., 161.Serono, C., 199.Serra, A., 258.Seydel, S., 221.Shepherd, E. S., 239.Sherrington, C. S., 185.Shorey, E. C., 217.Sidgwick, N. V., 22, 98.Sieverts, A., 36.Silber, P., 106, 110.Sirk, H., 299.Skita, A., 91, 92.Slyke, D. D. van, 179.Smedley, Miss I., 52.Smeeth, W. F., 248.Smiles, S., 131, 135, 136.Smith, A., 3, 4, 5, 6, 7, 21.Smith, E. F., 258, 265.Smith, G. F. H., 249, 263, 264.Smith, J. L., 199.Smith, R. G., 218, 219.Smits, A., 21.Smyth, L. B., 300.Sobecki, W., 87, 89.Soddy, F., 289, 291, 294.Soelher, J., 257.Sosman, R.B., 239, 241.Sowton, Miss S. C. M., 185.Spangenberg, O . , 141.Spengler, T., 138, 140.Speter, M., 164.Speyer, E., 90, 142.Spezia, G., 245.Spitalsky, E., 27.Stadnikoff, G. L., 89.Stiihler, A., 23, 158.Stanton, A. T., 212.Starck, G., 160.Staudinger, H., 109, 110.Stecher, E., 168.Steinmetz, H., 267.Stepp, W., 208.Stern, Mlle. L., 187.Stevenson, Miss E. F., 53.Stevenson, R., 156.Stewart, A. W., 52, 53.Stobbe, H., 55, 56, 107.Stock, A., 45.Stoddard, J., 168.Stoecklin, L., 173.Stoermer, R., 111.Stoklasa, J., 113, 226.;toll, A., 145, 146.Xxatton, J. A., 232.kernme, H., 253.itrubin, P., 140.ltrutt, (Hon.) R. J., 25, 278.;tutzer, A., 177, 178, 179.ludborough, J.J., 170.lutton, J. R., 249, 251.luzuki, S., 224.hedberg, T., 276.Cangl, F., 235.Casker, H. S., 53, 132.Caylor, R. L., 46, 47.Celetoff, I. S., 39.rhiele, C., 168.Choni, J., 174.Chomson, J. C., 29.rhomson, Sir J. J., 154, 155.Chorvaldson, T., 266.fhugutt, S. J., 249, 253, 255.I'iede, E., 36.rinkler, C. K., 140.I'ischkoff, P., 163.I'otfoczko, S., 243.I'6th, J., 175.Townsend, J. S., 283.Traube, I., 154.Trautmann, W., 166, 167.rschelinzeff, W. W., 89.I'schugaeff, L. A., 91, 133.l'uEai1, F., 250.Ulex, H., 175.Underhill, F. P., 186, 187.Ungemach, H., 253, 261.Usher, F. L., 299.Utzinger, M., 147, 148, 149, 150.Vaillant, P., 39Vanino, L., 39.Vavon, G., 91.Vernadsky, W. I., 258.Verneuil, A., 256.Vogt, T., 252, 254.Vogt, W., 136.Volk, W., 131.VotoEek, E., 113, 114, 115.Wagner, L., 246.Wahl, W. A., 265.Walden, P., 60.Wallace, R. C., 245.Wallach, O., 71, 73, 91.Walpole, G. S., 180.Warburg, O., 193.Warren, C. H., 253, 261, 263.Wdowiszewski, H., 163.Webster, A., 12.Weil, H., 158.Weiller, P., 241312 INDEX OF AUTHORS’ NAMES.Weinschenk, E., 267.Weisweiller, G., 117.Wells, R. C., 264.Welsh, T. W. B., 42.Werkhowsky, W., 37.Werner, A., 68, 77, 80, 81, 82, 83, 84,Weyberg, Z., 243.Wheatley, R., 103.Wheeler, E., 14.Wheeler, R. V., 33.Widmer, R., 142.Wieland, H., 141.Wilkie, J. M., 169.Willstgtter, R., 144, 145, 146, 147, 148,149, 150, 151, 227.Wilm, A., 36.Wilson, C. T. R., !275.Wilson, W., 280, 282.Woldrich, J., 267.Wolf, M., 44.Wood, J. T., 169.85, 86, 95.Wood, T. B., 232.Woodward, T. S., 19.Worley, F. P., 14.Wright, F. E., 239.Wright, R., 52, 53.Wunsch, D. F. S., 246.Wulf, T., 271.Wunder, M., 44, 254, 263.Yoder, P. A., 172.Zach, K., 116.Zaitschik, A., 235.Zambonini, F., 244, 251.Zdobnicky, W., 113, 226.Zelinsky, N. D., 92, 93.Zenghelis, C., 157.Zerewitinoff, T., 170, 171.ZimBnyi, K., 263.Zincke, T., 131, 134, 135.Zsuffa, M., 106.Zumbusch, E., 39

ISSN:0365-6217    

DOI:10.1039/AR9110800305

出版商:RSC    

年代:1911

数据来源: RSC

摘要:

INDEX OF SUBJECTS.Absorptive power, influence of un-Acapnia, 186.Aceanthrenequinone, 89.Acetaldehydephenylhydrazone, isomericforms of, 98.Acetic acid, trichloro-, crystallographyof salts of, 246.Acetic anhydride, estimation of, inacetic acid, 172.Acetoacetic acid, ethyl ester, isomericforms of, 100.equilibrium of, 104.Acetylacetone, isomerides of, 104.Acetylene di-iodides, 97.Achlusite, 248.Acids, interaction of alcohoIs and, 93.Aconitic acid, estimation of, 172.Adenase, 202.Adrenaline, detection of, 179.Aegirite, 253.Agricultural analysis, 177.Alanine, detection of, 179.Alcohols, interaction of acids and, 93.Aldehydes, aromatic, additive com-pounds of hydrogen persulphideand, 132.Aldoses, chemistry of the, 112.Alkalis, action of chlorine on, 4.6.Alkaloids, 137.estimation of, 170.AIlo hane, 253.d-AJ ose, 116.Allotropy, dynamic, 20.Alloys and metals, 35.d-Altronic acid, 115.d-Altrose, 116.Aluminium, test for, 158.alloys, 36.oxide (alumina) fused, 40.Alunite group, 253.saturated groups on, 52.Amino-acids, synthesis of, in the body,Amino-oxides, optically active, 75.2 - Amnlinediethylenediaminecobalticsalts, 1-bromo-, and 1-chloro-,resolution of, 80.Ammonia, amount of, in the atmo-sphere, 233.action of radium rays on, 299.Ammonium bases, quaternary, crystal-lography of derivatives of, 245.chloride, vapour pressure of, 6.Analysis, new method of chemical, 154.without the use of hydrogen sulphide,157.Anhydrides, aromatic, detection of,169.Animal tissues, manganese and vana-dium as constituents of, 196.Anthranol, isomerides of, 104.Anthrone, 104.hydroxy-, and its isomeride, 105.Anthraquinol and its isomeride, 105.Antimony, estimation of, 162.organic compounds, 129.Antipnein, 187.Apparatus, new, 155.Argon, fractional crystallisa tion of, 48.Arsacetin, 120.Arsenic, estimation of, la.organic compounds, 117.Arsenobenzene, 4 : 4'-diaminodihydroxy -,Arscno-o-cresoI, 124.Arsenomandelic acid, 124.Arsenophenylglycine, 124.p-Arseno-o-tolylglycine, 124.Arsinic acids, 118.nitration of, 125.reactions of, 121, In.193.analysis of, 179.123.31314 INDEX OF SUBJECTS.Arylarsenious oxides, preparation of,122.Arylarsinic acids, amino-, preparatiorof halogen derivatives of, 124.Assimilation in plants, 225, 230, 231.Asymmetry of carbon atoms, 73, 74.molecular, 71.htacamite, 253.Atmosphere, amount of ammonia inthe, 233.radioactivitv of the.300.Atomic weigh, 23. ‘theory of, 269.AzotobacteT in soils, 221.Bababudanite, 248.Barium, detection of, 158.and, 164.Batchelorite, 248.Bauxite, 254.Reaverite, 248.Benzoylacetic acid, methyl ester, iso-Berberine, absorption spectra of, 140.Beri-beri, 210.Bertrandite, 254.Beryl, 254.Bismuth ochre, 254.Bismutosphaerite, 254.Bleaching-powder, theory of the actionBlende, 254.Blomstrandine, 255.Blomstrandite, 255.Blood pressure, effect of choline on,Boiling points, determination of, 3.Bordeaux mixture, fungicidal actionBoron trioxide, hp$rates of, 40.Bread, “standard, 206.Cadmium peroxides, 39.Caesium magnesium chromate, 38.Calaverite, 255.Calcium, atomic weight of, 23.separation of calcium, magnesiummerides of, 104.of, 46.194.of saturated solutions, 3.of, 234.estimation of, 163.separation of barium, magnesiumseparation of strontium and, 164.carbonate, formation of, 225.cyanamide, analysis of, 177.nitrate, analysis of, 178.Cancrinite, 255Cantharidin, estimation of, 175.Caoutchouc, formation of, 108.estimation of, 176.Capillarity constants, investigation of,Carbamide, chloro-, 99.and, 164.154.Carbithionic acids, preparation of, 132.Carbohydrates, 112.formation of, 226.synthesis of, 113.Carbon atom, asymmetric, representa-tion of compounds containing an,67, 68.estimation of, in organic compounds,169.monoxide, interaction of chlorineand, 41.monosulphide, 24.telluride, 45.See also Diamond.Carborundum, ferriferous, 249.Casein, 188.osmotic pressure of, 12.Caseinogen, 188.Castor seeds, detection of poisonousconstituents of, 180.Catalyst, copper as a, 92.silver nitrate as a, 91.Catalytic action, 27.reactions, 92.Cheese, nitrogenous compounds in, 236.Zhemical action and electric discharge,24.and pressure, 245.change, influence of light on, 19.action of, on alkalis, 46.interaction of carbon monoxide and,41.3hlorophyl1, researches on, 144 e t seq.,227.>holine, effect of, on blood pressure,194.3hromic acid, action of, on hydrogenperoxide, 27.>hromium, detection of, 158.estimation of, 163.compounds, asymmetric, 85.>hromoisomerides, formulation of, 59.komoisomerism, 56.Xnchona alkaloids, syntheses in thegroup of, 142.Xnnamic acid, ethyl mter, polymerisa-tion of, 106.hnamic acids, isomerism of the, 55.Xnnamylideneacetic acid, u-cyano-,polymerisation of, 106.:Iimatology, physiological, 197.%ntonite group, 255.:obaIt, differentiation of nickel and,compounds, asymmetric, 77.salts, absorption spectra of, 17, 18.lobaltic salts, isomerism of, 85.:ocoanut oil, detection of, in butter,Yodeine, estimation of, 175.Zhlorine, atomic weight of, 24.158.173INDEX OF SUBJECTS.315Colloids, osmotic pressure of, 11.Columbium, separation of, 164.Combustion, 31.Conductivity, molecular, anomalousCongo--red, dialysis of, 12.osmotic pressure of, 11.Convolvulin, hydrolysis of, 113.Copper, use of, as a catalyst, 92.action of nitric acid on, 43.estimation of, 162.sulphate, reaction between hypophos-Corpus luteum, 193.Corundum, 256.Creatine, 198.estimation of, in urine, 180.Creatinine, 198.Crystallography, chemical, 245.Crystals, growth and solution of, 243.Cuprodescloizite, 256.Cuprous hydride, 39.curves of, 15.phorous acid and, 39.Dehydrothio-&naphthol, constitutionDensitv. determination of.154.of, 135.Descloizite, 256.Desmotropic substances, 100.Diamond, behaviour of the, a t hightemperatures, 40.Diazonium salts, formation of, 98.Diethylenediaminechromic salts,1 : 2-dichloro-, resolution of, 86..Diethylenediaminecobaltic salts, iso-merism of, 95.resolution of, 81.8-Diketonw, aliphatic, preparation of,88.as-Dimethylallene, polymerisation of,107.2 : 7-Dimethylphenanthraquinone, 89.Dioscorine, 143.Diphenylene, 97.Diphenylstibine chloride, 129.Diphenylstibinic acid, nitration of, 130.Disintegration, multiplle, 287.Disulphoxides, organic, decompositionof, 132.Divinyl, polymerisation of, 107.Dolomite, 256.Earth, radioactivity of the, 300.Eglestonite, 256.Eichbergite, 248.Elastin, use of, for the isolation ofpepsin, 190.Electric dimharge and chemical action,24.Electrical activity, development of,225.leak between platinum plates, 46.Electrochemical analysis, 168.Emplectite, 256.Enolic compounds, estimation of, 171.Enzyme, uricolytic, 202.Enzymes, 202, 204, 205.terminology of, 184.Epinatrolite, 249.Esters, catalytic decomposition of , 94.Ethyl ether, compounds of halogenEthylene, polymerisation of, 107.Ethylglyoxaline, amino-, synthesis of,Ethylenic isomerides, transformationEthylketencarboxylic acid, ethyl ester,Euxenite, 256.Fayalite, 257.Felspar group, 257.Fermorite, 249.Ferritungstite, 249.Flour, bleaching of, 209.Fluorine, estimation of, 160.Food-stuff s, chemistry of, 236.Fumaric acid, photochemical trans-formation of maleic acid into, 112.Gajite, 250.Garnet group, 258.Gas analysis, 156.Gases, adsorption of, by glass, 41.Geological age, determination of , 295.Glass, adsorption of gases by, 41.Glauberite, 258.Glaucodote, 258.Glucosides, production of , 117.Glycerol, valuation of, 176.Glycine, detection of, 179.Gnoscopine, synthesis of, 137.Gold, detection of, 158.bullion, =say of, 164.Goldschmidtite, 258.Guanase, 202.Hamatinic acid, 150.Haemoglobin, detection of, in urine,HEmopyrrole, 150.isoHEmopyrrole, 150.Halogen derivatives, preparation of,Halogens, estimation of, in organicHelium, 276.Herderite, 258.Hexahydrite, 250.Hexosw, 115.Hinsdalite, 250.double salts and, 95.143.of, by light, 111.isolation of, 109.ignition-points of, 31.influence of salb on the rotatorypower of, 15.180.87.compounds, 169316 INDEX OF SUBJECTS.Histidine, synthesis of, 144.Homochromoisomerism, 56Honey, detection of artificial invert.Howlite, 259.Hydrazine, preparation of, 42.action of sulphur on, 42.hydrate, action of sodium on, 42.Hydrazines, action of heat on, 100.Hydroaromatic compounds, reductionHydrochloric acid, origin of, in gastricHydrogen, occlusion of, 36.sugar in, 174.of, 91.juice, 191.solubility of, in metals, 36.action of compressed, on solutions ofdetection of, 157.estimation of, in organic compounds,peroxide, preparation of, 44.metallic salts, 37.169.action of chromic acid on, 27.decomposition of, by radium rays,Hydroxyl groups, estimation of, 171Hypaphorine, constitution of, 144.Hyperetbene, 259.Hypophosphorous acid, reaction be-tween copper sulphate and, 39.Ignition-points of gases, 31.Indium, isomorphism of thallium and,Inorganic analysis, 157.Iodine, estimation of, in organic com-tetroxide, 47.Ionisation, 282.Iron, atomic weight of, 23.catalytic action of, 27.rusting of, 29.estimation of, 165.Isomerides, equilibrium of, 103.estimation of enolic and ketonic, 101.Isomerism, 54.of cobaltic salts, 85, 95.Isoprene, production of, 108.Jamesonite, 259.Kairoline oxide, resolution of, 75.Kaolinite, 259.Ketens, 109.Ketones, condensation of, 110.Lead, separation of tin and, 36.monoxide, action of air on, 42.Light, absorption of, by inorganicinfluence of, on chemical change, 19.Linseed, protein of, 236.298.245.pounds, 169.salts, 16.Lipoids, 199.Lithium periodate, 38.Lublinite, 250.Luminosity of alkaline earth sulphides,Magnesium alloys, 36.39.caesium chromate, 38.rubidium chromate, 38.separation of barium, calcium and,164.organic compounds, use of, in syn-thetical work, 89.Magnetic susceptibility, 54.Maleic acid, .photochemical transforma-tion of, into fumaric acid, 112.Manganese in animal tissues, 196.Manures, 231.Marcasite, 260.Melting points, determination of, 153.Mercury, atomic weight of, 23.vapour pressure of, 5.action of nitric acid on, 43.estimation of, 161.alloys, 35.mercurous chloride (calomel), vapourpressure of, 7.estimation of, 163.Mesothorium-1, 297.Metabolism, 203.Metallic chlorides, anhydrous, prepara-tion of, 47.salts, action of compressed hydrogenon, 37.sulphides, luminosity of, 39.Metals, replacement of, in non-aqueoussolutions, 38.and alloys, 35.Meteorites, 265.Methyleneacetone, polymerisation of,106.Methylethyl-P-naphthylamine oxide,resolution of, 75.Methylglucosides, amino-, 116.1-Methylcyclohexylidene-4-acetic acid,optically active derivatives of, 71.Methylpentoses, 113.Microchemical reactions, 158.Milk, enzymes of, 189.estimation of water in, 173.Minerals, artificial formation of, 247.physical chemistry of, 239.Mispickel, 260.Molecular asymmetry, 71.Molengraaffite, 250.Molybdenum, estimation of, 166.Morganite, 251.Morphothebaine, constitution of, 141.Muthmannite, 251.Narcotine, synthesis of, 137INDEX OFN a t r am01 ygoni te , 251.Neocolemanite, 251.Neon, action of electric discharge on,Nepheline, 260.Nickel, catalytic action of, !27.Nicotine, estimation of, 174.Nitrates, production of nitrous andnitric oxides from, by bacteria,224.Nitriles, pre aration of, 90.Nitrites, anayysis of, 160.Nitrogen, chemically active modifica-estimation of, 160, 169.monoxide, estimation of, 156.dioxide, estimation of, 157.Nomenclature, sphysiological, 184.of radioactivity, changes of, 283.Nucleme, 202.Nucleases, 199, 201.Nucleic acid, 199.Nucleic acids, 205, 206.Nucleinases, 204.Nucleosidases, 204.Nucleosides, 201.Nucleotidases, 204.N ucl eo ti d ea , 200.Nutrition, animal, chemistry -of , 234.Olivine group, 260.Organic analysis, 169.compounds, physical properties of,50.Orthite, 261.Osmotic pressure, measurement of, 10.47.detection of, 158.differentiation of cobalt and, 158.tion of, 25.of casein, 12.of colloids, 11.of solutions of sucrose, 9.Oxalyl chloride, action of, on aromaticOxidising agents, use of peroxides as,estimation of activity of, 161.Oxonium salts, existence of, 89.Oxyberberine, synthesis of, 138.Oxydases, 202.Oxygen, solidification of, 44.Oxyluminescence, 133.Ozone, preparation of, 44.decomposition of, 28.Pancreatic diabetes, 187.Parisite, 261.Pearceite, 261.Pepsin, isolation and detection of, 190.Periodic system, cubic, 271.hydrocarbons, 89.90.estimation of, in organic compounds,169.IUBJ ECTS.317Peroxides, use of, as oxidising agents,Phenol, detection of, 169.Phenothlioxin, formation of deriv-Phenylarsinic acids, nitroamino-, 127.Phenylhydrazine, action of heat on, 99.Phenylmethylethylphosphoric oxide, re-8-Phenylpropionic acids, 8-hydroxy-,Phenylstibine dichloride, 129.Phenylstibinic acid, nitration of, 130.Phorone, reduction of, 91.Phosphorite group, 261.Phosphorus, dynamic allotropy of, 21.compounds, optically active, 76.monoxide, preparation of, 43.PhosDhoric acid as a solvent, 44.90.atives of, 135.solution of, 76.optical inversion of, 65.ph6nyl B-naphthyl and ‘p-tolylhydrogen salts, resolution of, 76Phosplhori; acids, a.Photochemical changes, 105.Photochemistry, 19.Phyllopyrrole, 150.Phytochlorin, 149.Phytol, 151, 152.Phytorhodin, 149.a-Pinene, reduction of, 92.Plant, growing, chemistry of the, 225.Plants, assimilation in, 225, 230, 231.germination of, 229.Plant tissues, changes in, 228.Platinum, native, 261.Plumbojarosite, 262.Pnein, 187.Poechite, 251.Polymerisation of unsaturated sub-Polymorphism, 54.Polymorphous substances, transf orma-Potassium, atomic weight of, 24.Powellite, 262.Pressure and chemical change, 245.Proline, estimation of, 179.Propionic acid, a-bromo-, illustration oftransformation of, into the amino-acid by Fischer’s model, 67.Protein, feeding experiments with, 192.Proteins, heat coagulation of, 190.Pyrargyrite, 262.Pyrites, 262.Quadriuratee, 188.Quinine, estimation of, 175.Quinones, additive compounds ofhydrogen persulphide and, 133.stances, 105.tion of, 243.detection of, 179.estimation of, 173.estimation of, 172318 INDEX OF SUBJECTS.Radioactivity of the earth and atmo-sphere, 300.Radio-elements, table of, 286.properties and preparation of, 291.periods of the longer-lived, 290.Radiothorium, 298.Radium, atomic weight of, 296.relation of uranium to, in minerals,rays of, chemical action of, 298.spectra of, 296.294.Radium-C, and -C,, 287.Radium-D, 297.Radium emanation, 296.a-Ray products, new short-lived, 283.a-Rags, 272.raige of, 274./%Rays, 278.y-Rays, 280.&Rays, 281.Reducing agents, 91.epiRhodeonic acid, 115.Rhodeose, configuration of, 113.isoRhodeose, 114.epiRhodeose, 115.Rhodizite, 263.Rice, analysis of, and its economicvalue, 212.Riebeckite, 263.Rinneite, 263.Rubidium magnesium chromate, 38.Salicylic acid, detection of, 169.Salt fusions, 241.Salts, hydration of, 33, 34, I 35.double, halogen, compounds of etherand, 95.inorganic, absorption of li h t by, 16.absorption spectra of, 1t coloured, absorption spectra of, 18.Salvarsan, 127.Scandium, separation of thorium and,164.Schwartzembergite 263.Selenium, preparatfion of colloidal solu-tions of, 45.Silicate fusions, 239.Silver alloys, 35.Sodium, test for, 158.nitrate, use of, as a catalyst, 91.hyposul hite, preparation of, 45.thiosulptate, as a standard inanalysis of, 177.alkalimetry, 167.Soils, 215 et seq.Soil bacteriology, 220.Solanine, investigation of, 117.Solutions, properties of, 13.non-a ueous, replacement of metalssaturated, boiling points of, 3.in, $.Soot, analyses of, 233.Spectra, absorption, of cobalt salts, 17,of coloured inorganic salts, 18.of inorganic salts, 16.18.Steel, analysis of, 164, 165, 167.Stereochemistry, 60.Stewartite, 251.Stibiotantalite, 264.Stitchtite, 251.Strontium, separation of calcium and,Striiverite, 264.Sucrose, osmotic pressure of solutionsSugars, formation of, 226.influence of aalts on the rotatorySulphates, estimation of, 159.o-Sulphobenwic acid, p-amino-, as aSulphonium-quinones, 135, 136.Sulphoxylic acids, organic, 131.Sulphur, dynamic allotropy of, 21.164.of, 9.power of, 15.8tandard in acidimetry, 172.organic compounds, 130.estimation of, in organic compounds,Tan liquors, estimation of acidity of,Tantalum, separation of, 164.Tellurium, atomic weight of, 24.Tetrahydroberberine, synthesis of, 139.Thallium, isomorphism of indium and,Thaumasite, 264.Thianthren, formation of, 132.rhioxanthone, synthesis of derivativesof, 131.Thorium, separation of, 164.Thorium-C, and -C2, 289.Thorium emanation, 298.Thortveitite, 252.Tilasite, 264.Tin, estimation of, 162.se aration of lead and, 36.Titanium, separation of, 164.trichloride, use of, in volumetricTriketohydrindene hydrate, use of, inTriphenylstibine hydroxynitrate, nitra-Toluene, photobromination of, 19, 112.Tungsten, estimation of, 167.Turpentine, valuation of, 175.Uranium, relation of radium to, in169.168.245.aliys, 35.analysis, 172.analysis, 179.tion of, 130.tri-m-amino-, 130.separation of, 164.minerals, 294INDEX OF SUBJECTS. 319IJranium, a-rays of, 273.hexafluoride, 46.minerals, 293.TJranium- Y , 288.Vanadium in animal tissues, 196.estimation of, 165.Vapour pressures, measurement of, 4.molecular weights deduced from, 8.Variscite, 265.Vaterite, 252.Vicianose, 117.Walden inversion, the, 60 e t seq., 65,Warrenite, 259.Water, boiling of, 2.69.Water, properties of, 1.vapour pressure of, 5.catalytic action of vapour of, 27.of crystallisation, 33, 244.decomposition of, by radium rays,Weight, atomic.See Atomic weights.molecular, deduced from vapour299.pressures, 8.determination of, 10.Yttrofluorite, 252.Zeolite group, 265.Zinc peroxides. 39.Zymase, 229R. CLAY AND SONS, LTD., BRUNSWICK ST., STAMFORD ST., S.E., AND BUNQAY, SUFFOLK

ISSN:0365-6217    

DOI:10.1039/AR9110800313

出版商:RSC    

年代:1911

数据来源: RSC