摘要:

ANNUAL REPORTSON THE:PROGRESS OF CHEMISTRYANNUAL REPORTSON THEPROGRESS OF CHEMISTRYISSUED BY THE CHEMICAL SOCIETY.HORACE T. BROWN, LL.D., F.R.S.A. W. CROSSLEY, D.Sc., Ph.D., F.R.S.H. R. DIKON, M.A., Ph.n., F.R.S.M. 0. FOI~STEI~, Il.Sc., Pli.D., F.K.S.C. E. GROVES, F.R.S.J.T.HEwITT, M.A.,D.Sc.,Ph.D.,P.R.S.A. MCBENZIR, M.R., D.Sc., l’11.D.Qomntiftee o f @ublicnfiou :R. XELDOLA, F.R,.S. a. T. MORGAN, D.Sc.A. Sco’rr, M.A., D.Sc., F.R.S.Sir I ~ W A I ~ I ) ‘l’irnitm, C. U . , LL. D.,Sir W I L L I A M RAMSAT, K.C.R., LL,D.,F.K.S.F. R. S.dlbilor :J. C. CAIN, D.Sc., Ph.D.Siib-6F;bifor :A. J. GILEENAWAY.~Cantribnt or9 :H. R. RARER, M.A., D.Sc., F.R.S.C. H. DESCH, D.Sc., Ph.D.A. D. HALL, M.A., F.R.S.W. D. HALLIBURTON, M.D., F.K,.S.A.HUTCHINSON, M.A., P1i.D.A. LAPWORI’H, D.Sc., F.R.S.A. R,. LING, F.I.C.F. SODDY, M.A., F.R.S.rr. M. L ~ ~ V I E I T , D . s ~ .Vole VII.L O N D O N :GURNEY & J A C K S O N , 10, PATERNOSTER ROW, E.C.1911RICHARD CLAY AND SONS, LIMITED,BREAD STREET HILL, E.C., ANDBUNCAY, SUFFOLKCONTENTS.PAGEGENEItAL AND PHYSICAL CHEMISTRY. By T. M. I ~ V I L Y , D.Sc. 1INORGANIC CHEMISTRY. By H. H . RAKER, M.A., D.Sc., F.R.S. . 26ORGANIC CHEMISTRY.LAPWORTH, D.Sc., F.R.S. . . . . . . . . . 57By CECIL H. DESCIK, D.Sc., Ph.D., and AWHURANALYTICAL CHEMISTRY. By ARTHUR I~OBERT LINQ, V.I.C. . . 157PHYSIOLOGICAL CHEMISTRY. By W. D. HALLIBURTON, M.D., F.R.S. 186By A. D. HALL, M.A., F.R.S. . . . . . . . . 208MINERALOGICAL CHEMISTRY.By AnTHuR HUTCHINSOX, &LA., Ph.D. 225RADIOACTIVITY. By FREDERICK SODDY, M.A., F.R. S. . , . 256AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGYTABLE OF ABBREVIATIONS EMPLOYED I N THEABBREVIATED TITLE.A . . . . . .Amer. Chein. J . . . .Amer. J. Physiol. . .Amer. J. Sci. . . .Analyst . . . .Annalen . . . .Ann. Chim. anal. . .Ann. Falsif. . . .Ann. qf Botany . . .Ann. Physik . . .Ann. Report . . .Apoth. Zeit. . . .Arch.. expt. Path. Pharm.Arch. Hygiene . . .Arch. Nkerland , . .Arch. Pharm. . . .Arch. Sci. phys. nat. . .Atti R. Accad. Sci. Torino.Atti B. Accad. LiiLcei .Bcr. . , . . .Ber. Deut. bot. Gcs. . .Ber. Deut. pharin. Ges. .Ber. Deut. physikal. Ges. .Bio-Chem. J. . . .Biochcm. Zeitsch. . .Boll.chim. farm. . .Bull. Acad. roy. Belg. .Bull. Acad. Sci. Cracow .Bdl. Acnd. Sci., St. Pkters-bourg . . . .Bull. Assoc. Chiin. Sucr.Dist. . . . .Bull. SOC. chin?,. . .Bull. Soc. chim. Belg. .Bull. Soc. franc. Illin. .Centr. Bakt. Par. . .Centr. Xin. . . .Chem. News . . .Chem. Weekblad . .Chem. Zeit. . . .Compt. rend. . . .Gazzetta . . . .J. Agric. Sci. . . .REFERENCES.JOURNAL.Abstracts in Journal of the Chemical Society. *American Chemical Journal.American Journal of Physiology.American Journal of Science.The Analyst.Justus Liebig’s Annalen der Chemie.Annales de Chimie analytique appliquEe ?L 1’IudustrieAnnales des Falsifications.Annals of Botany.Annalen der Physik.Annual Reports of the Chemical Society.Apotheker Zeitung.Archiv. fur experimentelle Pathologie und Pharmako-Archiv fur Hygiene.Archives Ndelandaises des sciences exactes etArchiv der Pharmazie.Archives des Sciences physiques et naturelles.Atti della Reale Accademia delle Scienze di Torino.Atti della Reale Aecademia dei Lincei.Berichte der Deutschen chemischen Gesellschaft.Berichte der Deutschan botanischen Gesellschaft.Berichte der Deutschen pharmazeutischeii Gesellschaft.Berichte der Deutschen physikalischen Gesellschaft.The Bio-Chemical Journal.Biocheinische Zeitschrift.Bollettino chimico farmaceutico.Acadeniie royale de Belgique-Bulletin de la ClasseBulletin international de 1’Acadhie des Sciences deBulletin de YAcademie ImpQrialc dcs Sciences doBulletin de l’dssociation des chimistes dc Sucrerie e tBulletin de la Societd chimique de France.Bulletin de la SociBtk chimique de Eelgique.Bulletin de la Socidtd fraqaise de MinQralogie.Centralblatt fur Bakteriologie, Parasitenkunde undInfektionskrankheiten.Centralblatt fur Mineralogie, Geologie und Palaeonto-logie.Chemical News.Chemisch Weekblad.Chemiker Zeitung.Comptes rendus hebdomadaires des Sdances deGazzetta chimica italiana.Journal of Agricultural Science.& l’Agriculture, & la Pharmacie et B la Biologie.logie.naturelles.des Sciences.Cracovie.St. Pdtersbourg.de Distillerie..,1’Acaddmie des Sciences.The year is not inserted insreferences to 1910viii TABLE OF ABBREVlATIONS EMPLOYED IN THE REFERENCES.ABBREVIATED TITLE.Jahrb.Min. . . ,Jahrb. Min. Beil-Bd. .Jahrb. Radioaktiv. Elektro-nik. . . . .J. Amer. Chem. SOC. . .J. Biol. Chem. . . .J. Chim.ph,ys. . , .J. Ind. Eng. Chem. . .J. Iron and Steel Inst. .LLandw.. . . .J. Path. Bad. . . .J. Pharm. C h h . . .J. Physical Chem. . .J. Physiol. , . .J. pr. Chem. . .J. fiy. ~ o c . New SOZ6tiWales . . . ,J. R,uss. Phys. Chem. SOC. .J. SOC. Chem. Id. , , .Landw. Jahrb. . . .Lccndw. Versuchs-Slat. .Mem,. Coll. Sci. E'ng., KgstaAfem. Jlanchestcr Phil. Soc.Milchw. Zenlr. . . .Min. Mag. . . . .Monatsh. . . . .P$dger's Archi"J. . .Pharm. Weekblad . .Pharm. Zeit. . . .Phil. 1Cfa.q. . . .Physikal, Zeitsch. . .Proc. . . . . .Proc. Amer. Acad. . .Proc. Amer. Physiol. Soc. .Proc.Cantb. Phil. Soc. .Proc. K. Akad. Wetensch.Proc. Physzol. Soc. . .Proc. Roy. Xoc. . . .Proc. Roy. Soc. Edin. .&tiart. Geol. floe. . .Aend. Accad. Sci. Fit?. Mat.Napoli . . . .Sci. Proc. Aoy. Dubl. Soc. .Sitzurysber. K. Akad. JViss.Tech. Q26ar.f. . . .Trans. . . . .Trans. Faraday SOC. . .Trans. Roy. Xoc. Canada .Y'sch. Min. Mitt. . .Zeitsch. anal. Chem. . .Amsterdam.Berlin.JOURNAL.Neues Jahrbuch fur Mineralogie, Geologie uiidNeues Jahrbuch fiir Mineralogie, Geologie undJahrbuch der Radioaktivitat und Elektronik.Journal of the American Chemical Society.Journal of Biological Chemistry, New York.Journal dc Chimic physique.Journal of Indiistrial and Engineering Chemistry.Journal of the Iron and Steel Institute.Journal fiir Landwirtschaft.Journal of Pathology and Bacteriology.Journal de Pharmacie et de Chimic.Journal of Physical Chemistry,Journal of Physiology.Journal fur praktischc Chemic.Journal of the Royal Society of Ncw South Wales.Journal of the Physical and Chemical Society ofJournal of the Society of Chemical Industry.J,andwirtschaftliche Jahrhiicher.Die landwirtschaftlichen Vcrsuchs-Stationen.Memoirs of the College of Qcience and Engineering,Kyat6 Imperial University.Memoirs and Proceedings of the Manchester LiteraryMilchwirtschaftliches Zentralblntt.Mineralogical Magazine and Journal of the Mineral-Monatshefte fur Chemie nnd verwandte Theile andererArchiv fur die gesammte Physiologie des Menschennnd der Thiere.Pharmaceutisch Weekblad.Pharmazeutische Zeitum.Palaeontologie.Palaeontologic. Boilage-Band.Bussia.and Philosophical Society..ogical Society.Wissenschaften.Philosophical Magazine @he London, Edinburgh andDublin).Physikalische Zeitschrift. 'Proceedings of the Cheniical Society.Proceedings of the American Academy.Proceedings of the American Physiological Society.Proceedings of the Cambridge Philosophical Society.Koninklijke Akademie van Wetenschappen te Amster-dam. Proceedings (English version).Proceedings of the Physiological Society.Proceedings of the Royal Society.Proceedings of the Royal Society of Edinburgh.Quarterly Journal of the Geological Society.Rendiconto dell' Accademia delle Sienze Fisiche eScientific Proceedings of the Royal Dublin Society.Sitzungsberichte der Koniglich Preussischen AkademieTechnology Quarterly.Transactions of the Chemical Society.Transactions of the Faraday Society.Transactions of the Royal Society of Canada.Tschermak's Mineralogische Mitteilungen.Zeitschrift fur analytische Chemie,Matema tiche-Napoli.der Wissenschaften zu BerlinTABLE OF ABBREVIATIONS EMPLOYED IN TRE REFEREKCES.jXABBREVIATED TITLE.Zeitsch. angew. Chem. .Zeitsch. artorg. Cheni. . .Zeilsch. Chenr. Id. Kolloide.Zeitsch. Elektrochern. . .Zeitsch. Kryst. Min. . .Zci2sc.h. Nahr. Genussnt .Zeitsch. physikaz. Chem. .Zeitsch. physiol. Chem.. .Zeitsch. Schiess. cmd Spreng-stoflwcsen . . .Zeitsch. Vw. deut. Zuckerind.Zeitsch. wiss. Photochem. .Zentr. Physiol. . . .JOURNAL.Zeitschrift fiir angewandte Chemie.Zeitschrift fur anorganische Chemic.Zeitschrift fur Chemie und Industrie der Kolloide.Zeitschrift fur Elektrochemie.Zeitschrift fiir Krystallographie und Mineralogie.Zeitschrift fiir Un tersuchung der Nahrungs- undZeitschrift fiir physikalische Chemie, StochiometrieH oppe-Seyler's Zeitschrift fur physiologische Chemie.Zeitsclirift fiir des Schiess- und Sprengstoffwesen.Zeitschrift des Vereins der deutschen Zucker-Zeitschrift fiir wissenschaftliche Photographie, Plioto-Zentralblatt fur Physiologie.Genussmittel.und Verwandtschaftslehre.Ind ustrie.physik und Photochemie

ISSN:0365-6217    

DOI:10.1039/AR91007FP001

出版商:RSC    

年代:1910

数据来源: RSC

摘要:

INORGANIC CHEMISTRY.No great outstanding discoveries have been made in this branchof the subject during the year, but many facts of great practicaland theoretical interest have been added to the literature. Atendency which becomes more and more marked year by year is thestudy of reactions in inorganic chemistry by physico-chemicalmethods. So much is this the case that the inorganic chemist. pureand simple has almost ceased to exist. The tendency is all for goodso long as the chemist does not mistake his means for the end. Theintroduction osf the methods of physical chemistry into organicchemistry has also made great strides, and it may be that, in thenear future, the distinction made in the abstracts published by thisand other societies may become so artificial as to lead to itsabolition.A tomic Weights.The International Committee decided to alter the time of thepublication of their report on the year's work on atomic weights, sothat students and others might have it in hand before the beginningof the acndemical year.It will not be necessary therefore for thisreport to deal with researches on this subject which were publishedin the earlier part of the year, unless they involve principles ofgeneral interest apart from the question of accuracy to the secondplace of decimals. One of the most important researches publishedis one which gives independent values for lithium, chlorine, andsilver.1 Great precautions to ensure the purity of material andaccuracy of manipulation were taken, and by the use of the com-parative insolubility of lithium fluoride, the lithium salts were pre-pared free from the salts of the other alkali metals.The ratio oflithium chloride to silver chloride was determined with two specimensof lithium chloride, prepared (1) by the decomposition of lithiumperchlorate, and (2) by conversion of lithium nitrate into carbonate,and thence into the chloride, by means of hydrochloric acid. Themean of seven determinations of the ratio AgC1: LiCl gave 6.940,1 T. W. Richards arid IT. H. Willard, J. Amer. Chem. Soe., 1910, 32, 4 ; A . , ii,292INORGANIC CHEMISTRY. 27and the mean of seven determinations of the ratio Ag: LiCl gave6.939 for the atomic weight of lithium (Ag= 107.880). The ratio oflithium chloride to lithium perchlorate was determined directly, theweighed lithium chloride being converted into the perchlorate bymeans of perchloric acid, and the perchlorate dried by fusion andweighed, Combining the ratio thus obtained, LiC1: 40, with theratio LiC1: Ag previously determined, the ratio Ag: 4 0 was cal-culated, and the atomic weight of silver deduced from thie ratiowas found to be 107.871, differing from the accepted value by 1 partin 12,000.I n the paper reference is again made to the unsatisfactory stateof our knowledge with regard to the atomic weight of silver.Theauthors state that, since most other elements are referred to oxygenthrough silver, their atomic weights cannot be accurately knownuntil the ratio between silver and oxygen is definitely established.It may be mentioned that experiments are in progress in the writer’slaboratory the object of which is the direct determination of thisratio by the analysis of silver oxide.The difficulty of the drying ofthis substance seems, if one may judge from preliminary experi-ments, to have been effectively surmounted.have deter-mined six ratios in the investigation of the atomic weight ofstrontium. The mean of twenty-nine determinations gives 87.646for the atomic weight.Mercury.-Continuing his work of last year,3 C. W. Easley haspublished a second paper,* which seems to confirm the abnormallyhigh number of 200.62 for this constant. The ratio HgClz: Hgwas studied, being determined (1) by a precipitation method, (2) byelectrolysis.Previous determinations by other workers have notbken altogether satisfactory, but an increase of more than 1 in 300 inthe atomic weight will scarcely be accepted without confirmation,especially as the author admits that one of the methods used wasopen to doubt.Tantalum.-The atomic weight of this element in the best pre-vious determinations shows discrepancies amounting to nearly twounits, and the new determination by C. W. Balke was much needed.Tantalum chloride was prepared by heating the oxide in a mixtureof chlorine and sulphur chloride vapour. By a process of frac-tional distillation, the sulphur chloride was separated from thetantalum chloride, the difference in boiling points being more thanlooo. The tantalum chloride was shown to be free from sulphur.TheProc. Roy. Soe., 1910, A, 83, 277 ; A., ii, 209.J. Arner. Chem. SOL, 1909, 31, 1207 ; A., 1909, ii, 1013.Ibid., 1910,32, 1117 ; A., ii, 957.Strontium.-Sir Edward Thorpe a.nd A. G. Francisa B i d . , 1127 ; A., ii, 96228 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ratio 2TaC1,: Ta,O, wits determined by allowing the chloride con-tained in a fused silica flask to hydrolyse slowly over water. Aftertwo or three days, liquid water and a little nitric acid were added,and carefully evaporated to dryness. It was finally iqnited in ablast flame. Eight determinations, which show satisfactory con-cordance, give an atomic weight for tantalum of 181.52 (C1= 35*46),a result which is 0.5 higher than the number last given by theInternational Committee.TeZZu&m.-From determinations of the loss in weight of telluricacid on heating, Marckwald6 drew the conclusion that the atomicweight of tellurium was 126*85, which would bring the element intoa normal position in the periodic classification. This result wascriticised 7 on the ground that, so far as had been investigated, saltswith water of crystallisation were untrustworthy as regards theconstancy of their water content.Marckwalds has now redeter-mined the atomic weight of tellurium, using the dioxide obtainedfrom telluric acid, which had been recrystallised several hundredtimes. This was converted into telluric acid by a volumetric process,and the mean atomic weight found was 127.61, thus confirming thework of former investigators.Marckwald now considers thattelluric acid crystals, in spite of being dried over phosphoric oxidef o r three months, still contain occluded water, a supposition whichthe writer, in an investigation which is to be published shortly, canfully confirm. Marckwald’s work again places tellurium beyondiodine in the periodic classification.W. R. Flint9 has extended his investigation of the behaviourof tellurium chloride when precipitated by water. More than 1000grams of the chloride, dissolved in a minimum quantity of hydro-chloric acid, were added to four litres of boiling distilled water, theprecipitated dioxide again dissolved in hydrochloric acid, and re-precipitated by water. After four such fractionations, the atomicweight of tellurium was determined, by converting the dioxide intothe basic nitrate and igniting again to the dioxide.The mean offour concordant determinations gave 126.59, a whole unit belowthe accepted number. Continuing the fractionation until it hadbeen repeated ten times, 23 grams of the dioxide were obtained,and seven determinations of the atomic weight gave a mean resultof 124.32. The less hydrolysed fraction was precipitated byammonia and ammonium acetate, the dioxide dissolved in hydro-chloric acid, and precipitated by water. This process was repeatedthree times, and 10 grams of dioxide were obtained. On frac-The work is being continued.6 Ber., 1907, 40, 4730 ; A., 1908, ii, 33.7 H. B. Baker, Chm. News, 1908, 97, 209 ; A ., 1908, ii, 483.9 Amer. J. Sci., 1910, [iv], 30, 209 ; A . , ii, 845.W. Marckwald and A. Foizik, Ber., 1910, 43, 1710 ; A., ii, 604INORGANIC CHEMISTRY. 29tionating this by adding ammonia to the boiling hydrochloric acidsolution, 8 grams of an oranga-coloured, crystalline substance, 2grams of yellow crystals, and 0.1 gram of a pale green substance wereobtained. These substances gave a black precipitate, m telluriumdoes, with stannous chloride, and tests made for copper, iron,tungsten, bismuth, and antimony gave negative results. No atomicweight determination was made with this less hydrolysable fraction.I n dealing with the earlier paper in last year’s report, it was shownthat the mean atomic weight of the original tellurium as calculatedfrom both fractions was 126.89.I n the newer work the authorhas determined the atomic weight of the material beforefractionation, and finds it to be 127.45. He concludes that thelowest number, 124.32, is the nearest approach which has yet beenmade to the atomic weight of the element. The work is of thegreatest interest; if confirmed, it would remove one of what havebeen called “ t h e three blots of Mendeldeff’s scheme.” The workreads most convincingly, and it seems to have been done with greatcare, but the large number of methods which have been unsuccess-fully tried previously for the resolution of tellurium makes onecautious in accepting Flint’s most st-riking results. A possibilityof it mistake in the work seems t o be the presence in his telluriumof two impurities, one of higher and one of lower equivalent, whichwould accumulate in the end fractions.The work is, for this reason,now being repeated by the writer in conjunction with Dr. A. VernonHarcourt, Professor Marckwald having most generously lent for thepurpose a large quantity of his highly purified telluric acid.Molecular Weights.Several researches have been described during the year on thesolution of iodine in various solvents. The view of the differencebetween the violet and the brown solutions taken in last year’sreport, was that in the brown solutions combination had taken placebetween the iodine and the solvent, whilst the violet liquids werepurely mixtures of iodine and the solvent. This view is, to someextent, supported by the work of P.Waentig,lo although he con-cludes that in the violet solutions some association takes place. Thework was mainly spectroscopic in character. On heating violetsolutions, displacement took place towards the red end of thespectrum, that is, towards the position of the band in iodine vapour.On allowing the solution to cool, the original position of the bandis regained. With many brown solutions, on the other hand, apermanent alteration of the absorption spectrum is observed. Theauthor believes that since brown solutions in thiophen and liquidlo Zeitsch. physikal. Ckrn., 1909, 68, 513 ; A., ii, 11730 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.sulphur dioxide become violet on heating, regaining their colouron cooling, there is only a difference of degree between the violet andthe brown solutions. The heat of solution in different solvents isnegative, except in pyridine, and from this last solution a compound,PyI,, has been isolated, but the heat absorption is much less forbrown than for violet solutions.The partial pressures of thesolutions indicate that, even a t the boiling point, there is con-siderable association between iodine and the solvent in brown solu-tions. The experiments recorded above, however, may be reconciledwith a different hypothesis. Amann l1 has submitted solutions ofiodine to observation with the ultramicroscope. He finds that theviolet solutions in carbon disnlphide, carbon tetrachloride, andchloroform, and the yellowish-brown solutions in aniline, dimethyl-aniline, and phenol are devoid of ultramicroscopic particles. On theother hand, large numbers of particles are seen in the brown soh-tions in ethyl and methyl alcohols, acetone, and aqueous sodiumiodide, and also in the violet solutions given by various petroleums.Benzene, toluene, acetic acid, and water give solutions which containfew particles.The ultramicroscopic character of many of thesolutions is largely altered when the solution is exposed to light. Onexposure of benzene and toluene solutions, large numbers of particlesare formed with great rapidity, and the colour changes to yellowish-brown. In the dark these solutions regain their violet colour, andthe ultramicroscopic particles disappear.The molecular weights of neon and helium have been redeter-mined by Watson.12 A quantity of a gas rich in these two con-stituents was given by M.Claude to Sir W. Ramsay, and served asthe source of the purified gases used in the experiments. The useof diffusion through a heated silica tube was first tried for separatingthe two gases, since it was known that helium passed through sucha tube. The rate of passage of the gas through the tube, heated to1200°, was extremely slow, and it was also found to be mixedwith neon. The process was therefore abandoned, and Dewar'sprocess of fractionating by means of charcoal cooled by liquid airwas used. The molecular weight of neon was found to be 20.20,and that of helium, 3.994.Corn Z, u s tion.No one has done so much to throw light on the processes whichtake place when substances burn as Professor H.B. Dixon. Fromthe time of Boyle, many great names have been connected with thestudy of this part of the subject', but it may safely be said that noresearches have penetrated so deeply into the nature of the chemicall1 Zeitsch. Chem. Ind. Kolloide, 1910, 6, 235 ; A . , ii, 496.l2 Trans., 1910, 97, 810INORGANIC CHEMISTRY. 31processes involved, as those which are associated with the name ofthe President of the Society. The researches are seen to be of thegreater importance when it is considered that they involve thestudy of the simplest of all chemical changes, and it is here, ifanywhere, that the chemist will attain a knowledge of what is thenature of the force of chemical attraction. In the latest of hisinvestigations, which formed the subject of the PresidentialAddress,l3 Professor Dixon describes experiments which confirm thefact that water vapour is necessary to initiate the reaction ofhydrogen and oxygen at comparatively low temperatures.I n theexplosion of these gases, however, his experiments lead him to thebelief that the action takes place directly. The evidence for theseviews must seem to all chemists extremely strong, and there isnothing inconsistent in the idea that in the great rapidity ofmovement, and the intense local energy that is developed in a gaseousexplosion, the splitting off of electrons, or whatever other cause iseffective in the chemical union, may take place without the inter-mediary which is apparently necessary when the union is less violent.It seems to the writer that we shall never know the essential facts ofa gaseous explosion without a more complete study of the natureof the electric spark, which is perhaps the least complicated of themany ways in which an explosion may be originated.One questionwhich remains to be settled is whether the difference of actionbetween a strong and a weak spark, which is so very manifest inan explosive mixture, is in any way connected with particles dis-rupted from the electrodes, or whether the effect is due entirely tothe greater heat and light developed in the stronger spark. Dixonmentions his many experiments made t o find out if sparks couldbe passed in dried electrolytic gas; whatever the nature of themetallic electrodes, an explosion always resulted, but it may berecalled that extremely minute and yet visible electric sparks havebeen passed in the mixture without apparent result.14 Dixonproceeds t o discuss the three arguments which have been adducedin favour of the hypothesis that hydrogen peroxide is the firstproduct in the flame of hydrogen and oxygen: (1) that hydrogenperoxide is found in the water rapidly condensed from such a flaae;(2) that the mixture of equal volumes of the gases is more sensitivet o the action of a spark; (3) that the mixture in equal volumeshas a lower ignition-point than any other mixture.With regard tothe isolation of hydrogen peroxide from the products of combustionof hydrogen in oxygen, Dixon suggests that, since ozone is alsoproduced,l5 it may easily be that an atom of oxygen may combinel3 Trans., 1910, 97, 661.l4 H.€3. Baker, ibid., 1902, 81, 404.l5 hlanchot, Ber., 1909, 42, 3948 ; A., 1909, ii, 99332 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.with a molecule of water previously formed, and that the hydrogenperoxide is produced in this way, and not by direct union. Whennitrous oxide is substituted for oxygen, only a trace of hydrogenperoxide is formed, and although the analogy of the two experimentscannot be pushed too far, in the case of the nitrous oxide there isa less chance of splitting off an oxygen atom. In the explosion ofhydrogen and oxygen, no trace of hydrogen peroxide has beendetected, although one would think that if that substance werethe primary product of the union of the gases, no more favourablecircumstances could exist for the formation and continued existenceof so endothermic a compound.The high temperature and suddencooling behind the flame would be precisely the conditions whichone would think necessary for a high yield of hydrogen peroxide.With regard to the second argument, it has been shown by Cowardthat the mixture of equal volumes of hydrogen and oxygen is notthe most sensitive to the spark, since further addition of oxygenincreases the sensitiveness. The third argument, that the mixtiireof hydrogen and oxygen in equal volumes has a lower ignition-pointthan any other mixture, rests mainly on the experiments of Falk.10I n these, the ignition-point of the gaseous mixture was determinedby finding the compression caused by a moving piston necessary tocause the gases to unite.Falk assumes that when the pistonreaches the point, it is instantaneously stopped. Dixon, on theother hand, by photographing the explosion produced by adiabaticcompression on a rapidly moving film, has shown that the equi-molecular mixture of oxygen and hydrogen takes an appreciabletime for combination. The piston therefore moves while theexplosion is taking place. By an ingenious arrangement, Dixonwas able to stop the piston at the point when the explosion justbegan, and the experiments showed that there was a progressivedecrease in the temperature of ignition of mixtures of hydrogen andoxygen from 3H2+0, to H,+40,.Hence the last argument forthe direct formation of hydrogen peroxide in the flame falls to theground.From what has been said above, it is obvious that the problemrequires help from the physical side. Physicists are, however, tooapt to neglect the chemical aspect of their studies and, in investi-gating these physico-chemical problems, to look upon the purity ofw-aterials as an unimportant factor. A striking exception to thisis found in the work of the Rev. P. J. Kirkby. His work on thecatalytic action of platinum on the union of hydrogen andoxygen a t low pressures,17 and on the chemical action of thel6 J. Amcr. Chem. Soc., 1906, 28, 1517; 1907, 29, 1536; A . , 1907, ii, 18, 946.l7 Phit.Mag., 1905, [vi], 10, 467 ; A., 1905, ii, 695INORGANIC CHEMISTRY. 33electric discharge,]* is quite exceptional in the care that has beentaken to use the best and most refined chemical methods. Thetheory put forward in the latter paper assumes that the chemicalaction is due to molecular dissociation effected by the collisions ofgaseous ions constituting the current with the molecules of the gas;the atoms are thus set free to enter into new combinations. Anaccount is given of experiments designed to determine both thenumber of molecules of water formed by the passage of the atomiccharge through 1 cm. of the positive columns of various dischargesin electrolytic gas, and also the electric force within these columns.The experiments support the hypothesis that the water vnpour isformed by the collision of an atom of oxygen and a molecule ofhydrogen.The experiments also prove that dissociated atoms ofoxygen are not charged electrically. The latter result is confirmedby recent experiments of the writer with F. E. Thomas, whichshow there is no leakage of electricity in a tube in which ozone isundergoing dissociation.The examination of the electrical conductivity of flames is likelyto give considerable help to the understanding of chemical com-bination in these circumstances. A considerable amount of workin this direction has been acqomplished by Haber and his students.It is shown19 that with a large supply of air the electrical con-ductivity of the inner green cone of the Bunsen burner is com-paratively high.Epstein and Krassa20 show that as electrodes aregradually lowered into a flame from the top, the electrical con-ductivity increases regularly, but there is a sudden increase whenthe luminous zone is reached. When the proportion of oxygen,mixed with the coal gas, is gradually diminished, the change inconductivity on reaching the luminous zone is less sudden. Thereis thus a close connexion between the luminosity of a flame(separation of free carbon) and the electrical conductivity. Thewriter cannot help feeling that there is some connexion betweenthis fact just established and the fact that all the gases, on thecombustion of which the absence of water seems to have no influence,are compounds of carbon (CS,, C,N,, CH,, C,H,, C,H,).Reference must be made here t o a most admirable report onCombustion by W.A. Bone.21 The facts are most clearly set forth,and it should be in the hands, not only of all students, but ofall chemists.Compare Chem. News, 1910, 102, 299.l9 F. Haber and B. S. Lacy, Zeitsch. physiknl. Chcm., 1909, 68, 726 ; A., ii, 122.'") Ibfd., 1910, 71, 28 ; A . , ii, 202.21 Brit. Assoc. Report, 1910. llepriiited in C76evb. A'eu~s, 1910, 102, 259.REP.-'VOL. VII. 34 ANNUAL REPORTS ON THE PROQRESS OF CHEMISTRY.Solution and Water of Crystallisation.An interesting paper on the solubility of some sparingly solublesalts has been published by Melcher.22 The salts used were silverchloride, barium sulphate, and calcium sulphate. The solubility wasdetermined by a conductivity method at 18O, 50°, 156O, and 218O,a platinum-lined bomb being used. The solubilities, in milli-equivalents per litre, of the first two salts were: silver chloride,0*0105 at 1 8 O , 0.0365 at 50°, and 0.0147 at looo; barium sulphate,0.0190 at 18O, 0.0212 at 25O, 0.0288 a t 50°, 0.0334 a t looo. Thesolubility of calcium sulphate was different according t o the varietyof salt used as the starting point, thus affording another example ofwhat Mendelheff imagined to be an argument against the dissociationtheory of solutions. Thus, gypsum gave a solubility of 29.5 at 18O,30.0 at 50°, 23.3 at looo; soluble anhydrite gave a solubility of22.8 at looo and 6.4 a t 156O; anhydrite gave a Solubility of 9.2 atlooo, 2.7 at 156O, and 0.7 at 218O.The solubility of calcium carbonate in solutions of ammoniumsalts may of ten be of serious consideration in quantitative analysis.It is pointed out by Rindell 23 that, at 25O, the solubility of calciumcarbonate in solutions containing 500 millimols.of the followingsalts per litre is, for ammonium chloride, 5.008, ammonium nitrate,5.267, and triammonium citrate, 66.87. It is also shown that theprecipitation of calcium oxalates in presence of ammonium salts,especially the citrate, is not complete.Further investigations on the chemical behaviour of substancesdissolved in solvents other than water have been made byA. Naumann.24 I n ethyl aceta5e solution, ammonia and hydrogensulphide react to form white crystals of ammonium hydrosulphide.With excess of hydrogen sulphide, yellow polysulphide is formed.Ammonium chloride is precipitated when a solution of ammoniain ethyl acetate is treated with hydrogen chloride. Mercuric chlorideis easily soluble in ethyl acetate, and hydrogen sulphide gives withthe solution a precipitate of the composition HgCk,ZHgS, whilstammonia precipitates the substance HgC12,2NH,.The boiling-point method gives 254.9-269-2 for the molecular weight ofmercuric chloride in ethyl acetate solution. The bromide and iodideof mercury behave in a similar manner, although their solubility isless. Potassium mercuri-iodide in ethyl acetate solution gives noprecipitate with either ammonia or hydrogen sulphide. Stannouschloride is converted into a stannic salt by both chlorine andJ.Amer. Chem. SOC., 1910, 32, 50 ; A., ii, 293.23 Zeitsch. physikal. Chem., 1910, 70, 452 ; A . , ii, 294.Ber., 1910, 43, 313 ; A., ii, 211INORQANIC CHEMISTRY. 35bromine, and even when present in oxcess reduces mercuric chlorideonly to mercurous chloride. The experiments are of importance asregards the dissociation theory, especially as it is shown that themolecular weights of all the salts determined are practically normal.A remarkable series of experiments has been made on potassiummercuri-iodide by J. E. Marsh.25 The salt KHgI,,H,O crystallkeswell from alcohol; it is soluble in a very small quantity of water,but is decomposed by excess. In a sealed tube, it melts in its waterof crystallisation a t 1190.In ether which has been shaken upwith water, the salt is completely soluble, but, on warming, crystalsof the monohydrate separate out. When potassium iodide andmercuric iodide are allowed to remain with undried ether, themonohydrated double salt is formed only after some weeks. I f ,however, ether which has been dried by sodium is used, and con-sequently water is not available, the two mixed salts graduallypass into solution, and a heavy yellow liquid is formed, whichcontains one molecule of the mercuri-iodide and four molecules ofether. Any excess of ether above the amount required for theformation of the compound floats above the heavy liquid. If theether is not present in sufficient quantity to form the compound,part of the solid salts are left undissolved.The compoundKHg13,4Et,0, on being exposed to dried air, loses ether and becomescrystalline, and the author believes that the crystals have the com-position KHgI3,3Ek0. The behaviour of the heavy liquid with smallquantities of water exhibits many interesting phenomena. Manysimilar compounds containing ether are described, and the fact thatthe ether apparently exists in definite molecular proportions, withoutnecessarily forming crystals, exhibits a type of association whichseems to be intermediate between that of water of crystallisationand definite chemical combination.The number and. composition of hydrates of salts have been studiedby Cumming.2B Attention is drawn to t'he doubt which exists aboutthe hydrates of even a salt like sodium carbonate, of which no fewerthan twelve have been described, although other workers haveasserted that only two or three have a seearate existence.Defectsare pointed out which are inherent to both the solubility methodand the calorimetric method of identifying hydrates, and it isshown that the vapour-pressure method is capable of giving verysatisfactory results. The basis of the method is an observation ofAndreae,27 that if three hydrat'es of a salt be placed in a closedvessel, the highest will lose water to the lowest until there are onlytwo hydrates in the system. The principle was used by Walkerp5 Trans., 1910, 97, 2297. 26 Ibid., 593.27 Zeilsch. physikaE. Chem., 1891, 7, 241 ; A., 1891, 781.D f 36 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.and Beveridge 28 in the isolation of p-toluidine monohydrate.Theauthor applies i t t o the investigation of the hydrates of sodiumcarbonate. The monohydrate wi19 first prepared by placing in thesame desiccator a large quantity of anhydrous salt and a small,weighed quantity of the decahydrate. In three days, the loss inweight showed that it had been converted into the monohydrate,and after nine day% more no further loss in weight was observed.To prepare the next higher hydrate, a mixture of anhydrous sodiumcarbonate and its decahydrate was made in such a proportion thatthe mixture contained, as a whole, one molecule of sodium carbonateto one molecule of water. After keeping it in a closed space forthree weeks, this mixture was used to dehydrate a weighed quantityof decahydrate, and it was found that in seven days the latterhad lost almost exactly three molecules of water, and there waspractically no further loss in three days more.No hydrate couldbe found by this method between the heptahydrate and the deca-hydrate. The reverse process was also attempted of forming theheptahydrate by exposing the anhydrous salt t o an atmosphere inwhich a large quantity of a partly effloresced specimen of the deca-hydrate was also present. The hydration reached a point where 6.93molecules of water were present to 1 molecule of the salt in ninety-sixdays, and no further increase in weight took place during a furtherexposure of one hundred and twenty days.The highest hydrate wassimilarly produced by exposure to an atmosphere containing asaturated solution of the salt. Only three hydrates thereforeprobably exist : Na&03,H20, Na2C03,7H20, and Na&03,10H;0.A possible explanation of the larger number of hydrates of sodiumcarbonate which have been described is afforded by a further paperby Cumming.29 A large specimen of sodium carbonate had beenleft to effloresce in a partly closed case for twenty years. By deter-mining its loss on ignition only, it wits thought to correspond roughlywith the formula Na&3O3,3H2O, but further investigation showedthat it was really the sesquicarbonate, Na,&!03,NaHC03,H,0. Theauthor suggests that the crystals described as Na&03,4H20 werereally the bicarbonate.The action of calcium carbide on hydrated crystals has beeninvestigated by Irvine Masson.30 It was found that many salts werecompletely dehydrated by shaking them with excess of calciumcarbide at the ordinary temperature.The acetylene evolved wasmeasured over mercury in a manometer, and served as a means ofestimating how much water had entered into reaction with thecarbide. With some salts (those which have a high water-vapour28 Tram., 1907, 91, 1797.30 Tmns., 1910, 97, 851.ga Chem. Newq 1910, 102, 311INORGANIC CHEMLSTRY. 37tension), the action is very rapid, about half a gram beingdehydrated in thirty seconds. In several cases the action only beginsa t looo, and in others incomplete dehydration is found even attemperatures as high as 170°, even where there is no question, asin the case of barium chloride, BaCI,,ZH,O, of the existence ofwhat Graham termed “ water of constitution.” With other salts,such as copper sulphate, CuS04,5H20, the amount of true waterof crystallisation is sharply defined, 4-02 molecules entering intoreaction as the temperature is raised to looo.An interestingexample is oxalic acid, C2H,O4,2H2O, the water of which reactedin the cold, without chemical action taking place between the oxalicacid and the calcium hydroxide. The method may have some valuein the study of the method of combination of water of crystallisationwith salts.The Rusting of Iron.The attempts which have been made towards the solution of theproblem of the cause of the rusting of iron have been very numerous,and the additional facts brought to light during the year make itpossible to give a useful summary of our knowledge of the subject.Until comparatively recently, the action was supposed to be one ofdirect oxidation. Crace-Calvert 31 attributed the action to thepresence of carbonic acid.Crum Brown32 supported this idea,imagining ferrous carbonate and hydrogen to be the first products;the hydrogen was supposed to combine with the oxygen dissolvedin the water, and the ferrous carbonate oxidised to rust by thesame agency; the carbon dioxide liberated in the latter action wouldbe then capable of recommencing the cycle of operations, and sothe rusting would proceed indefinitely. Traube,33 having shownthat hydrogen dioxide was produced during the action of water onseveral metals, imagined that this substance was also a precursorof the rusting of iron, although he was unable to detect its presencein water in which rusting had taken place.Dunstan, Jowett, andGoulding s4 considered that their experiments proved that rustingwould take place in absence of carbon dioxide, and they supportedstrongly the view held by Traube. Moody,35 however, finally dis-posed of the hydrogen peroxide hypothesis by showing that brightiron would go on catalytically decomposing redistilled hydrogendioxide for some weeks without any rusting taking place. Thehydrogen dioxide must, in fact, have inhibited the action, since all31 Mnnchester Lit. Phik. Mcnt., 1871, 5 , 104.32 J.Iron mtd Steel Znst., 1888, 11, 129.33 Ber., 1885, 18, 1877 ; A . , 1885, 1105.35 Ibid., 1906, 89, 720.Trans., 1905, 87, 154838 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the conditions for rapid rusting were fulfilled, the oxygen beingeven in the Moody further pointed out that theboiling of water for a short time would not get rid of the lasttraces of carbon dioxide. By very carefully purifying water andair, he was able to keep the three substances, air, water, and iron,in contact for a prolonged period without rusting taking place. SirWilliam Tilden,36 however, objected to Moody’s experiments on theground that in purifying the surface of the iron he had used adilute solution of chromic acid, and hence rendered the iron passive.Repeating the experiments with great care, Tilden drew the con-clusion that commercial iron would always rust in presence of waterand air.It should be pointed out, however, that Moody showedthat if a little carbon dioxide was allowed to pass into the tubecontaining the bright iron in the purified water, rusting a t oncetook place. Many attempts have been made by the writer to makeiron passive to ordinary water by treatment with dilute chromicacid, but all have been unsuccessful. The writer is of opiniontherefore that Moody must be given the credit of having provedthat water, iron, and air, when in a purified condition, do notinteract. I n 1903 Whitney37 propounded a theory of rusting,according to which an acid is not necessary.Since the purest wateryet attained is slightly dissociated, metallic iron would pass intosolution as ferrous hydroxide. Tilden supports the theory,supposing that either the impurities or even the harder parts ofthe metal form couples with the purer iron. Attention may bedrawn to the fact, which strongly supports Tilden’s last suggestion,that in almost all cases rust, forms on iron in spots, which only slowlyextend over the surface of the bright metal. Walker, Cederholm,and Bent 38 believed that they had confirmed Whitney’s contentionthat iron will dissolve to an appreciable extent in pure water, butas Friend has pointed out, their result is probably vitiated by thefact that traces of carbon dioxide were not altogether excluded bytheir method of working.Friend,39 who has made many experimentson the subject, also shows that the bacterial explanation of rustingis untenable, and confirms Moody’s work. The latest investigationby Lambert and Thomson 40 contains by far the most elaborate andcareful work that has been done on the subject. It is perhaps notgenerally recognised that work of this kind demands an amount ofcare and precaution very far beyond what would be thoughtnecessary in, for instance, ilr good atomic-weight determination,nascent ” state.36 Trans., 1908, 93, 1356.37 J. Anter. Chem. SOC., 1903, 25, 394 ; A., 1903, ii, 430.38 Ibid., 1907, 29, 1251 ; A . , 1907, ii, 875.4u Trans., 1910, 97, 2426.J. Iron and Steel Innst., 1908, 77, i, 2, 5 ; A,, 1908, ii, 698INORGANIC CHEMISTRY.39Iron was obtained of a very high degree of purity by electrolysingpurified ferric chloride, using iridium electrodes. The irondeposited was converted into ferric nitrate by means of very purenitric acid, and this salt repeatedly crystallised from nitric acid.The salt was ignited in an iridium boat, and reduced to metal inhydrogen, obtained by the only method which gives the gas inanything like a pure condition, namely, the electrolysis of a solutionof carefully purified barium hydroxide. The iron was contained ina silica testrtube, which was enclosed in a tube of Jena glass.Water was distilled from a dilute solution of barium hydroxide,without actual boiling, through a trap to prevent any possibility ofthe hydroxide being carried over. The experiment was so arrangedthat the water vapour which was ultimately condensed on to theiron was condensed only on silica.Oxygen, prepared by the electro-lysis of barium hydroxide, which has been shown by many workersto be free from ozone and other impurities, was admitted to thetube containing the iron. I n these circumstances the three sub-stances, iron, water, and oxygen, were found to be capable of contactwithout chemical action for some months. Moody’s contentiontherefore is amply confirmed, but it must not be considered thatthe question is finally set at rest. I n some of Lambert andThornson’s experiments, rusting undoubtedly took place, althoughcarbon dioxide and other impurities were excluded. For the sakeof comparison, mention may be made here of recent experimentson a similar subject.41 It has been shown that water can beobtained by careful distillation in such a state that it exhibitsscarcely any action on sodium amalgam.The purity of this water,measured by its electrical conductivity, is not of a very high order,and yet it exhibits a chemical inertness greater than that of water,which, measured by the same standard, is considerably purer. Thewriter suggests, with some diffidence, the hypothesis that it ispossible that oxygen in solution may be, in some circumstances, dis-sociated, and in others not dissociated, and that in the latter caseonly it exhibits chemical activity towards metals. Experimentsnow in progress should give a definite decision on this point.Metals and Alloys.Small quantities of strontium have been prepared in a crystallinecondition by Guntz and Galli0t.~2 Anhydrous strontium oxide,mixed with the calculated amount of powdered aluminium, washeated in a steel tube surrounded by an exhausted porcelain tube.A temperature of 1000° was maintained for four hours, and, on41 H.B. Baker, Trans. Faraday Soc., 1910, 6, 120.42 Compt. rend., 1910, 151, 813 ; A., ii, 106440 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.cooling, silver-white crystals, containing 99.4 per cent. of the metal,were obtained.Metallic strontium has been prepared in quantity by B. L.Glascock 43 by the electrolysis of fused strontium chloride. Veryconsiderable trouble was experienced on account of the formation ofcarbide and an iron alloy from the electrodes, and also because themetal does not, like calcium, adhere to the cathode.Strontium ismore oxidisable than calcium, and so soft that it can easily be cutwith a knife. It reacts with water, methyl and ethyl alcohols, andacetoacetic and malonic esters with evolution of hydrogen. Stron-tium burns in carbon dioxide as readily as it does in air, formingsome carbide and free carbon. The hydride is formed by directunion with hydrogen. Analysis of the metal showed that it con-tained 1.5 per cent. of impurity. The specific heat was found tobe 0.0742, and conforms to Dulong and Petit’s law, giving 6.5 asthe atomic heat.Metallic radium has been prepared by Mme. Curie andA. Debierne.44 The method was based on the preparation of $heamalgam and subsequent expulsion of the mercury.The amalgamwas produced by the electrolysis of a solution of radium chloride,using a mercury cathode and an anode of platinum-iridium. Theweight of radium chloride used was 0.106 gram, and that of themercury about 10 grams; the amount of radium chloride left inthe solution was 0.0085 gram. The amalgam was quite liquid,whereas a barium amalgam prepared under the same conditionscontained crystals. Radium amalgam decomposes water, andchanges rapidly in the air. After drying, it was rapidly transferredto an iron boat, which was heated in a silica tube in hydrogen.The heating must be performed with very great care, since, if themercury is allowed to boil, some of the radium is lost.The tem-perature was determined by a thermoelectric junction connected t othe boat. It was found that hydrogen, purified and dried by theordinary methods, attacked the amalgam and the metal. Theauthors state that by passing the gas through a red-hot platinumtube, they obtained “perfectly pure hydrogen.” Most of themercury was distilled off at 270°, and the temperature was raised.The pressure of the hydrogen waB increased at the same time, inorder to prevent the mercury boiling. At 400° the amalgam wassolid, but melted at a higher temperature. A t 700° no furthervolatilisation of mercury was noticed, but radium began to vaporiseand attack the silica tube. The boat then contained a bright metal,which melted sharply at 700O.It was difficult to detach the metalfrom the iron.43 J. Rmcr. Chein. Soc., 1910, 32, 10 ; A . , ii, 954.a Compt. rend., 1910, 151, 523; A . , ii, 816INORGANIC CHEMISTRY. 41Metallic radium rapidly alters in air, becoming black, probablyowing to the formation of a nitride. When a particle of the metalwas dropped on to white paper, blackening was produced as if thepaper was burnt. When the metal is placed in water, energeticdecomposition takes place, and most of it dissolves, showing that thehydroxide is soluble. The insoluble residue is probably nitride, andsince it is completely soluble in dilute hydrochloric acid, it is certainthat the mercury had been completely removed. Since the metalis more volatile than barium, the authors propose to use the frac-tional sublimation of the metals in a vacuum as a means of obtain-ing pure radium from the mixed radium barium preparations.This has been shown to be feasible by Ebler,45 although a verymuch smaller quantity of the radium bromide was used.Onemilligram of radium barium bromide, containing 9 per cent. ofradium bromide, was converted into radium barium azoimide. Thiswas heated in a very small glass tube, contained in a larger tube,which was kept vacuous. After being kept for some hours a t atemperature of 180-250°, a shining metallic mirror was farmed,which was sealed off from the residue, and found to contain 73 percent. of the radium in the original substance used.Prandtl and Bleyer 46 have investigated the production of metallicvanadium by the thermite process.When vanadium pentoxide andaluminium are fired in a magnesia crucible, reduction only takesplace to a lower oxide. Metallic calcium mixed with the aluminiumproduces vanadium, but the impurities in commercial calcium renderthe resulting vanadium impure. The authors find, however, thata much purer metal is obtained by using a mixture of 100 parts ofvanadium pentoxide, 49.5 parts of aluminium, and 20 parts ofcalcium fluoride.The production of metallic tungsten has been studied byL. we is^.^' The thermite process with wolframite is very violent,but it can be made manageable by using deficiency of aluminium.The resulting metal contains 90 per cent. of tungsten, and part of theimpurity, consisting mainly of manganese and iron, can be removedby hydrochloric acid. Electrolysis of tungstic acid fused withcryolite gives a metal containing 96 per cent.of tungsten, but it isnot coherent. The best product, which contained 99 per cent. oftungsten, was obtained by fusing tungsten trisulphide with lime.The metal is not magnetic, and is to some extent malleable. It isonly slowly attacked by aqua regia, and it can only be brought intosolution by a mixture of nitric and hydrofluoric acids.I n a research on zirconium by L. Weiss and E. Neumann,48 the45 Ber., 1910, 43, 2613 ; A . , ii, 1024.47 Zeitsch. nnorg. Chem., 1910, 65, 279 ; A . , ii, 216.je Ibid., 248 ; A,, ij, 217.'46 Ibid., 2602 ; A., ii, 107542 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.metal was prepared by the ordinary methods, and it was found thatwhen the powder was compressed into rods by pressure, it conductedelectricity. Previous observers had stated that the metal is a non-conductor.The authors confirm the existence of zirconium hydride,first prepared by Winkler.49 The hydride has been prepared bydirect union of the metal with hydrogen, and burns in oxygen,forming Zr,O,.The alloys of magnesium and gold have been investigated byUrazoff .so They were obtained by heating the constituent metalstogether in a graphite crucible enclosed in an iron vessel with ascrew top. Combination took place a t 700O. Four compounds wereindicated by the freezing;point curve, namely, AuMg, with amaximum at 1150°, AuMg,, with a maximum at 788O, Au,Mg,,with a break in the curve at 7 9 8 O , and AuMg,, with a maximuma t 8 1 8 O .Continuing the researches published last year, Charpy andBonnerot51 have applied more rigorous methods in order to findif the cementation of iron takes place when carbonising gases areeliminated as far as possible.Soft Martin steel, containing prac-tically only iron, carbon, and a little manganese, as well as varietiesuf carbon, sugar-charcoal, purified graphite, and white diamonds,were heated in separate tubes to 1000° in a vacuum to get rid ofoccluded gases. The iron and carbon were t,hen brought together,and to purify them still further were heated t o 700° in a vacuum.The temperature was then raised to 1000° and kept so for severalhours, the vacuum pump being continually worked.I n thesecircumstances no cementation took place with any of the varieties ofcarbon. The authors have not succeeded in compressing the carbonand iron together in a high vacuum, but it is probable that in viewof their experiments of last year, cementation would not have beeneffected by the increased pressure.It has been noticed that fracture in steel often takes place at anarea lying between two parts where segregation has taken place,the proportion of carbon being different on the two sides of thefracture. It was found by Giolitti and Tavanti52 that suchsegregation could be avoided by it process of cementation. Acurrent of carbon dioxide was passed over purified carbon, and thenover the steel, both heated to a high temperature.In these circum-stances, the outer layers of steel, a t all events, receive an evendistribution of carbon, and there is no abrupt change of high tolow carbon steel.4@ Ber., 1890, 24, 888 ; A., 1890,1372.50 Zeilsch. anorg. Chem., 1909, 64, 375 ; A . , ii, 43.51 Compt. rend., 1910, 150, 173 ; A., ii, 215.52 Atti. h!. Accad. Sci. Torino, 1910, 45, 539 ; A., ii, 780INORGANIC CHEMISTRY. 43The conditions which determine the composition of electrcldeposited alloys have been investigated by Field.53 The effect onthe composition of brass, electrolytically deposited from cyanidesolutions, was determined when the following conditions werevaried: (tz) composition of the solution; ( b ) strength of the solu-tion; ( c ) temperature; (d) current density; (e) presence of freecyanide.It was found that, in absence of free cyanide, copper wasthe more easily deposited of the two metals when they were presentin about equal proportions. I n the same circumstances, increaseof current density increases the percentage of zinc deposited, anda similar effect is produced by diluting the solution. Rise in tem-perature, on the other hand, increases the proportion of copper,and this i t , also the case if free cyanide is introduced. I n a furtherpaper,54 the author has examined the co-deposition of silver andcopper, which he finds only takes place within very narrow rangesof conceni,ration. From the sulphates and nitrates, silver isdeposited done, even when a very large quantity of copper is present.The deposition of copper is promoted by diminution of the relativeamount of silver, the use of cyanide solutions, the increase of currentdensity, and the lowering of the temperature.Some work has been done on the amalgams of mercury and silverby H.Chapman Jones.55 They were prepared by the preparation ofdouble salts of the metals, or of a mixture of salts in molecularproportions, and subsequent reduction by means of sodium sulphiteor ferrous Dxalate. The amalgam AgHg, prepared by the reductionof AgHgCl,, had a specific gravity of 12-80 ; if no contraction hadtaken place, the calculated specific gravity would be 12.29. Joule 56obtained an amalgam by direct union of the metals with a specificgravity of 14.68.The solubility of gases in metals and alloys has been the subjectof an extended series of investigations by Sieverts and his assistants.57The metals were heated in vessels of porcelain. The authors finda result which will be surprising, and, if it can be confirmed, verywelcome to chemists, that Meissen biscuit porcelain is impenetrableto hydrogen a t 1650°, and that vessels of this material will remainvacuous up to 1400O.An electric furnace was used for the heating,temperatures being estimated by means of a Wanner opticalpyromet'er. It has been proved that hydrogen is not absorbed bysilver, either in the solid or the melted condition, and this is truealso for zinc, cadmium, thallium, tin, lead, antimony, bismuth andJs Trans. 2'araday SOC., 1909, 5, 172 ; A., ii, 38.54 Ibid., 1910, 6, 1 ; A ., ii, 851.56 Jozbrn. Chem. Soc., 1863, 16, 383.67 Zeitsch. physikal. Chem., 1909, 68, 115; A . , 1909, ii, 1004; Ber., 1910, 43,55 Tracns., 1910, 97, 336.893 ; A., G,!410 ; Zeitsch. physikal. Chem., 1910, 74, 277 ; A., ii, 85144 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.gold. Hydrogen dissolves in copper both when i t is solid and whenit is fused. At constant pressure, the solubility in solid copperincreases in a linear manner as the temperature rises; at the meltingpoint there is a sudden increase in solubility, and the solubility thenincreases linearly up to 1500O. A t 623O, 100 grams of copperdissolve 0.08 milligram of hydrogen, so that the earlier deter-mination of the atomic weight of hydrogen must have been slightlyaffected by this cause.At constant temperature, the amount ofhydrogen absorbed by fused copper is proportional to the squareroot of the pressure.The solubility of hydrogen in solid palladium is stated to bepractically independent of the temperature, a statement which iscontrary to the experience of other workers. When the palladiumis melted, there is a sudden fall in the solubility of hydrogen. Thesolubility of hydrogen in copper is not affected when the metal isalloyed with silver, it is increased by alloying with nickel orplatinum, and it is diminished by alloying with gold, tin, oraluminium.Sulphur dioxide is insoluble in solid copper, but dis'solves to aconsiderable amount when the metal is fused, and the solubilityincreases when the temperature rises.It is remarkable that, as withhydrogen, the solubility is proportional to the squase root of thepressure, 'since the ordinary explanation of dissociation of themolecule of hydrogen can scarcely be imagined to hold in the caseof sulphur dioxide.The experimental number for the solubility of oxygen in moltensilver obtained by Sieverts has been confirmed by Donnan andShaw.58 They find that for 10 grams of silver, 20.5 C.C. of oxygen(measured at Oo and 760 mm.) are absorbed a t 1020O. The authorscalculate that the freezing p i n t of silver saturated with oxygenshould be lowered by 1 0 . 4 O ; the actual lowering is only 7O.Group I.Purists will no doubt object to the use of the term " dry nascenthydrogen" used in a very interesting series of papers byVournaso.s.59 The reducing action of sodium formate at about 400°has been applied to the formation of the hydrides of sulphur,phosphorus, and arsenic, the vapour of the element being passedover the heated formate.By mixing sodium antimonite with thesodium formate, stibine was formed ; hydrogen boride and hydrogensilicide are likewise produced in small quantity when boron58 J. SOC. Chem. I n d . , 1910, 29, 987 ; A . , ii, 844.59 Corrqt. rend., 1910, 150, 464 ; A., ii, 286 ; Ber,, 1910, 43, 2264; A,, ii, 951 ;Ibid., 2272 ; A., ii, 948INORGANIC CHEMISTRY. 45and silicon am heated with the formate. Hydrogen selenide andhydrogen telluride are likewise produced, but, as is natural, theproportions of the hydrides are limited by their dissociation.Yields, however, of 12 to 17 per cent.by vdume have been obtainedof hydrogen arsenide. When sodium formate is heated with com-pounds containing two volatile constituents, such as the sulphidesof phosphorus, arsenic, and antimony, or the phosphides of arsenicand antimony, mixtures of the corresponding hydrides are produced.Nitrides of the metals give ammonia, but silicides, borides, andcarbides are not affected. The author recommends the process as asubstitute for Marsh's test in certain circumstances; it is possibleto detect 0-001 milligram of arsenic. The writer, in repeating someof these experiments, found that hydrogen containing a considerablepercentage of boron hydride could be obtained by using powderedboron trioxide instead of boron.Ths long and patient investigation of the photochemical inhibitionof the interaction of hydrogen and chlorine has been continued byD.L. Chapman and P. S. MacMahom60 It has already been shownthat oxygen, nitrogen chloride, and the gas formed by nitric oxideon moist chlorine (either nitrogen peroxide or nitrosyl chloride,according to the authors) act as inhibitors, while carbon dioxide,nitrogen, and nitrous oxide act only as diluents. Ozone and chlorinedioxide must now be added t o -the inhibitors, whilst chlorinemonoxide, when free from oxygen, behaves as a neutral gas. Ozonewas found t o disappear quickly when left in the dark mixed withthe hydrogen and chlorine.A research of extreme difficulty has been accomplished by Wenz 61on the determination of the velocity of sound in potassium vapour.The vapour was contained in a steel tube enclosed in one of porcelain,which was heated electrically to 850O.The steel tube was internallycoated with silver. One end of the steel tube was closed by a plateof mica, which served for the vibrating resonance diaphragm, whilea movable piston closed the other end. The distances betweenwhich resonant vibration could be observed were determined andcompared with the corresponding lengths in air. The ratio ofspecific heats found was 1.77, and the conclusion is drawn fromthe experiments that potassium vapour is monatomic. The experi-ments thus confirm the measurements made of the vapour densityof the metal.An ammoniacal derivative of cuprous nitrate, CuN0,,2NH3, hasbeen prepared by Sloaa,62 by allowing a solution of cupric nitratein liquid ammonia to remain in contact with metallic copper.Thesubstance is colourless, but it rapidly oxidises in the air.Ann. Physik, 1910, [iv], 33, 951 ; A., ii, 1061, 6o T~ans., 1910, 97, 845.8? J. Amer. Chem. Soc., 1910, 32, 972; Ar, ii, 85246 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The colour of cupric salts ha,s been the subject of an investigationby Rassenfo~se.~3 Dissenting from the views of Donnan andB a s ~ e t t , ~ ~ the author believes the colour to depend on two factors:(a) the dissociation of the salt; ( b ) on its hydration. He adducesevidence to show that the colour changes of cupric chloride producedby (a) heating, ( b ) the addition of hydrochloric acid, ( c ) the additionof alcohol, are due to the formation of additive products of thesalt, or by its dissociation.The addition of hydrochloric acid, forinstance, to a cold saturated solution of cupric chloride produces aprecipitate of a hydrate of cupric chloride, so that the colour changecannot be produced by dehydration. Zinc chloride, added to agreen solution of cupric chloride in dilute hydrochloric acid, restoresthe blue colour, probably owing to the decomposition of the com-pound of cupric chloride and hydrogen chloride. Calcium chlorideand magnesium chloride change the blue colour of an aqueoussolution of cupric chloride to green, probably owing to the formationof compounds of the salts with the cupric chloride, since a mixtureof saturated solutions of calcium and cupric chlorides deposits amass of greenish-brown, deliquescent crystals of 2CuCl2,CaC1,,6H2O.When an aqueous solution of cupric chloride is heated, the colourchanges to green, and hydrogen chloride is found in the aqueousvapour given off, and since the boiled solution has an increasedresistance, the author concludes that it contains cupric hydroxide.The writer finds, however, that by heating a blue solution of cupricchloride in a sealed tube, the solution turns green on heating tolooo, and in this case there can be no loss of hydrogen chloride.When alcohol is added to a blue aqueous solution of cupric chloride,a green solution is formed, and this fact has been attributed tothe dehydrating action of the alcohol.The author shows, however,t'hat greenish-yellow crystals of CuCl$2C2H,*OH can be obtainedfrom a solution of anhydrous cupric chloride in absolute alcohol.In connexion with this subject, an experiment perfQrmed in thewriter's laboratory may be worth quoting. The blue colour ofcrystals of copper sulphate is usually attributed t o the presence ofcupric ions, and in spite of the comparative immobility of theseions, one would expect the crystal to show some electrical con-ductivity. A dry crystal, however, i n found to be, on the contrary,a non-conductor to a very marked degree.What are called crystalline photochlorides of silver have beenprepared by Reinders 65 by allowing it solution of silver chloridein ammonia t o crystallise in sunlight.The crystals were indigoblue in colour, and were found to contain about 1 per cent. ofBid?. Acad. roy. Belg., 1909, 1289 ; A., ii, 210.64 Pi-am,, 1902, 81, 939.65 Chem. Weekblad, 1910, 7, 961 ; A,, ii, 1062lNORGANIC CHEMISTRY. 47colloidal siIver. The crystals became reddish-brown on furtherexposure to light. There is little doubt that the crystals were thewell-known AgC1,2NiH,. They rapidly colour in light, but the oxy-chloride of silver is not formed in this case, since it would be atonce reduced to metallic silver by the ammonia. The fineness ofdivision of the silver would obviously account for the differences incolour observed.Group ZI.The action of various hydrocarbons on metallic magnesium hasbeen examined by Nov6k.66 The products obtained in the differentexperiments were decomposed by water ; the acetylene was estimatedby absorption with cuprous chloride, and the allylene by silvernitrate.Two carbides, MgC, and Mg,C,, were found to be pro-duced. When acetylene was passed over the heated metal, reactionbegan at 400°, MgC, being principally formed. As the temperatureis raised, the amount of the carbide increases up to 490°, whichis the most favourable temperature for its formation. A t 460° thecarbide Mg,C, can be detected in the product, and the proportionincreases up to 545O. A t higher temperatures, carbon is set free,which at 700° increases so much as to block up the tube.Theproportion of free carbon formed is greater in a steel tube thanin a porcelain tube, as would be expected from the behaviour ofacetylene when heated alone. I n it porcelain tube, benzene andother hydrocarbons are produced, whilst in it steel tube the gasbreaks up into carbon and hydrogen.When methane is used instead of acetylene, the formation of freecarbon is less when the temperature is as low as 560°, but at 780°the proportion of carbon is greater than when acetylene wasemployed. Pentane, octane, benzene, toluene, and the three xylenesgave results very similar t o those obtained with methane. Theprevailing reactions are supposed to be: at about 570°,2MgC, = Mg,C, + C; and above 610°, Mg,C, = 2Mg + 3C.The research of R.L. Taylor 67 on bleaching powder is not con-cerned with the constitution so much as with the chemical behaviourof this substance. It consists of the determination of the relativeamounts of chlorine and hypochlorous acid which are given off whenbleaching powder is submitted to the action of air, with or withoutthe presence of carbon dioxide. An ingenious method for estimatinghypochlorous acid and chlorine in a mixed solution consisted intreating the solution with N / 10-sodium arsenite.As,O, + 2C1, + 2H,O =A%O, + 4HC1As,03 + 2HOC1= A%O, + 2HC188 Zeitsch. physikal. Chew, 1910, 78, 513 ; A . , ii, 778.67 TTans., 1910, 97, 2541.The equations 48 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.show that, for the same amount of arsenite used, twice theamount of chloride is produced in the case of chlorine asin the case of hypochlorous acid.The arsenite is added in excess,and the solution divided into two parts. I n one the excess ofarsenite is determined by N/lO-iodine solution, and in the otherthe chloride produced is estimated by silver nitrate. Carbondioxide, passed over bleaching powder, was found to producechlorine alone; if the carbon dioxide was previously dried by calciumchloride, no difference was found in the product, but the action wasmuch retarded. Chlorine alone was also obtained when thebleaching powder was suspended in water, the action being muchaccelerated. Hence the author very reasonably concludes that theaction of carbonic acid is similar to that of any other acid, and thatit acts not only on the hypochlorite, liberating hypochlorous acid, butalso on the chloride, forming hydrogen chloride, and that these twoproducts, as usual, react to produce chlorine and water.It wasasserted by Muller 68 that sodium chloride is decomposed by carbonicacid, the presence of hydrochloric acid in the solution beingdemonstrated by the decolorising of ultramarine. The writer canconfirm the difficulty experienced by Taylor in observing this lossof colour. It can only be seen if the ultramarine is very dilute,and its colour compared with some of the untreated solution.Taylor demonstrates the fact of the formation of hydrochloric acidin a much more satisfactory way by the use of methyl-orange.Ordinary moist air passed over bleaching powder or through asolution of bleaching powder in water brings off a t first hypochlorousacid and chlorine, and later almost pure chlorine. The deductionfrom this is that calcium hypochlorite undergoes slow hydrolysis, thehypochlorous acid being swept out with the chlorine, produced asabove by the action of carbonic acid.The action of chlorine onalkalis is a reversible one, like that of bromine and iodine; if thefree calcium hydroxide is removed, the reverse action proceeds.This explains the reason of the impossibility of preparing bleachingpowder free from lime. The author adduces evidence to show thatin the process of bleaching by the use of bleaching powder, thebleaching is mainly carried on by chlorine, and only to a slightextent by hypochlorous acid.The paper is an admirable one, ofgreat theoretical as well as of practical interest.The beautiful dark red compound produced by the action ofbromine on calcium hydroxide, discovered originally by Berzelius,has been shown by L. G. Killby, in the writer’s laboratory, tocontain bromine in three forms, as bromide, hypobromite, and asbromine more loosely combined. The bromide and hypobromite are08 Journ. Chem. Soc., 18i0, 23, 36INORGANIC CHEMISTRY. 49in equivalent proportions, so that it contains a true bromine bleach-ing powder. The loosely combined bromine, to which the compoundowes its red colour, is in some form of combination which has notyet been completely established, but it is probably present as aperbromide of calcium.A paper has been published by Wilks,69in which the absorption of bromine from carbon tetrachloridesolution by calcium hydroxide is described. With weak solutionsof bromine, the concentration of bromine in the lime increases withthe concentration of the solution, pointing t o the formation of anadsorption pro,duct. With more concentrated solutions of bromine,the quantity taken up is independent of the concentration and theratio Ca(OH)2: Br =4*42 : 1, indicating the formation of a com-pound. With dry slaked lime, the ratio soon becomes constant at14.9: 1. The colour of the product increases until the constantconcentration is reached.Group ZII.The substance known as crystalline boron always contains foreignelements derived from the substances used in its preparation.Biltz70 has obtained yellow crystals by a thermite process, themixture used being 50 grams of boron trioxide, 100 grams ofaluminium, 75 grams of sulphur, and 2 grams of soot.After theaction is over, the cooled mass is treated with water and withconcentrated hydrochloric acid. The residue mainly consists oftransparent, yellow crystals, which are quadratic, and mixed withthem are black crystals. They are separated by flotation inmethylene iodide. Both substances have been previously described ;the yellow crystals obtained by Hampe71 were said to have theformula C,B,,Al,. The author finds a slightly different composition,represented by the formula C,B,,Al,. There is no evidence as tothe question of the crystals being a mixture or a compound.Kohn-Abrest 72 has investigated the effect of heating metallicaluminium in a porcelain tube to llOOo in a vacuum.A t first themetal volatilises readily, but after some time no further sublimationtakes place. It is shown that a silicide of aluminium, Al,Si, isproduced, which, mixing with the metal, appears to raise its boilingpoint. The same effect is produced if the aluminium is isolated fromthe porcelain tube in a boat of graphite, which would seem toindicate that in one form or another the silicon must have passedthrough a vapour phase.69 Proc. Cnneb. Phil. Soc., 1910, 15, 526; A . , ii, 1063.70 Ber., 1910, 43, 297 ; A., ii, 201.72 Compt. rend., 1910, 150, 185 ; A., ii, 212.Annalen, 1876, 183, 75 ; Joum.Chem. Xoc., 1877, i, 273.REP.-V OL. VIT. 50 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Artificial sapphires were obtained fifty years ago by Deville andCaron, but their results could not be obtained by subsequentworkers. Verneuil,73 however, by heating alumina with 1.5 per cent.of magnetic oxide of iron and 0.5 per cent. of titanic acid in thereducing part of the oxyhydrogen flame, has produced crystalswhich are identical in properties with the natural stones. Thecolour is due to the presence of lower oxides of iron and titanium.An interesting paper by Parsons and Evans74 shows that whensolutions of the alums are allowed to diffuse through a membrane,they are more or less completely sepaated, the authors believe, intothe component simple sulphates.The chrome alums are morecompletely separated than the aluminium alums. It would seempossible, however, that it may be a question of hydrolysis of thesulphates of the triad metals, colloidal hydroxides being formed.The most exact investigation which has yet been made of thecompounds of scandium has been continued by one of the veteranPast Presidents of the Society, Sir William Crookes.75 No less thantwentytwo new salts, both of inorganic and organic acids, havebeen prepared and examined, with the minute care which the wholescientific world is accustomed to associate with the name of theauthor.Group ZV.The direct synthesis of methane, which was indicated by Bone andJerdan 76 and confirmed by Bone and Coward,77 has again been thesubject of very careful work.Pring,7* taking great precautions asto the purity of materials, and using three varieties of carbon,graphite, gas-carbon, and sugar-charcoal, has confirmed the f a c t ofthe direct synthesis of methane, and has also shown that, whilstacetylene does produce methane at high temperatures, the methaneproduced at lower temperatures is produced by direct union of itselements. Bone and Coward, who had previously obtained 73 percent. of the theoretical yield of methane when small quantities ofcarbon were used, have, by the use of improved apparatus, obtainedalmost the whole of the carbon as methane, three experiments giving91, 95.6, and 95.8 per cent. respectively of the theoretical quantity.In the analysis of the hydrogen used, the authors state that the0-007 per cent.of methane present in the gas is probably anexaggerated estimate. The writer, who has used much largerquantities in analysing the gas prepared by the same process, theelectrolysis of barium hydroxide, found that no hydrocarbon7s Compt. rend., 1910, 150, 185 ; A., ii, 212.T4 J. Amer. Chem. Soc., 1910, 32, 1378 ; A., ii, 1069.75 Phil. T m n s , 1910, 210, A, 359 ; A., ii, 714.77 ]bid., 1908, 93, 1975 ; 1910, 97, 1219.Trans., 1897, 71, 41 ; 1901, 79, 1042." lhid., 1910, 97, 498INORGANIC CHEMISTRY. 51impurity at all could be detected in the gas. He is of opinion thatthe authors have adopted too low an estimate of the percentage ofmethane that they have obtained.I f they have erred, however, ithas been on the side of caution.Some new metallic carbonyls are described in a paper 79 drawn up,just before his death, by the late Dr. Ludwig Mond. It is to thisindefatigable worker that we owe the original discovery of theseinteresting substances, as well as the application of their formationto technical processes. Cobalt carbonyl, CO(CO)~, is prepared frommetal reduced from the oxide at 300° by a current of hydrogen.The metal is heated from 150-250° in carbon monoxide at 3 0 4 0atmospheres pressure. The higher the pressure, the greater is theproduction of the compound up to 250 atmospheres, the highestpressure used. Fine orange crystals are produced, which meltwithout decomposition at 51O. Slow decomposition takes place at60°.The molecular weight determined by the cryoscopic methodshowed the formula Co2(CO),. A new compound, having the com-position corresponding with the formula Co(CO),, is obtained byslow heating, but it is too sparingly soluble to get cryoscopicmeasurements. A hexacarbonyl of molybdenum has also beenprepared at a minimum pressure of 150 atmospheres and a tem-perature of 2 0 0 O . A carbonyl of ruthenium probably is capable ofexistence, but no similar compounds were obtained with manganese,chromium, tungsten, palladium, or rhodium.The reaction between nickel carbonyl and thiocarbonyl chloridehas been shown by Sir J. Dewar and H. 0. Jones8O to produce thelong-sought-f or carbon monosulphide, or a polymeride of this sub-stance. It is a brown solid, which is not altered by dilute sulphuricacid.The concentrated acid gives a purplish-brown solution, which,on dilution, precipitates the monosulphide unchanged, a behaviourwhich recalls the similar action of concentrated su'rphuric acid onsulphur, selenium, and tellurium. Concentrated nitric acid gives ared solution, which is only slowly changed by boiling. When heat'edto a low red heat in a vacuum, carbon and carbon disulphide areobtained. In continuation of the work,81 the authors investigatedthe influence of the silent electrical discharge on carbon disulphidevapour a t low pressures. When the gas produced was passedthrough a tube cooled by liquid air, carbon monosulphide was con-densed with the unchanged disulphide. When the temperature isallowed to rise, the substance polymerises t o form the brown sub-stance described above.It is, however, not all decomposed whenthe mixture of the new gas with carbon disulphide is heated to440O. So many different substances, prepared in so many different7y Mond, Hertz, and Cowap, Trans., 1910, 97, 798.8o Proc. Roy. Soc., 1910, 83, A, 408; A., ii, 408. Ibid., 526 ; A., ii, 408.E 52 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ways, have been described under the name of carbon monosulphidethat it is highly satisfactory to get evidence of its real existence,such as is given in these two papers. bythe same two authors describes the action of nickel carbonyl oncarbon disulphide and other substances. It was proved by laboriousinvestigations that carbon monosulphide was not produced in theseactions. The effect of pressure on carbon monoxide has been studiedby Briner and Wroczynski.83 At 800 atmospheres pressure at theordinary temperature? no change took place in the gas.At 320°,however, and under a pressure of 600 atmospheres, a contraction of10 per cent. took place in twenty hours. Carbon dioxide was found,and a greyish-black deposit, which was probably carbon. The authorsuggests that, as Berthelot supposed, a lower oxide of carbon mayhave been formed. Gautier84 has repeated Berthelot's work onthis subject, and has failed to find any indication of a suboxideof carbon. When carbon monoxide, prepared by the method usedby Berthelot, is heated strongly, no deposit of carbon is found,but since it contained moisture, the author suggests that, insteadof forming free carbon, a hydrocarbon is produced.A considerable amount of discussion has taken place with regardto the percarbonates, but it is considered that a summary of thepoints involved will be more useful if it is deferred until theexperimental evidence is made more complete.Silicon monosulphide has been obtained by Cambi 85 by heatingferrosilicon with sulphur in an electric arc furnace.The com-pound sublimes in two forms at 940° a t reduced pressure, namely,a black solid and a yellow powder, the yellow modificationbeing condensed on the cooler parts of the tube. Both forms, onanalysis, appear to ha,ve the formula SiS. The black varietydissolves in water with the evolution of hydrogen sulphide andthe formation of soluble silicic acid, whilst the yellow modificationgives hydrogen sulphide and forms a white, insoluble substancewhich evolves hydrogen when treated with alkalis.Still a further researchGroup V .The effect of radium emanation on ammonia has been investigatedby Usher.86 According to his results, ammonia is decomposed bythe emanation at the ordinary temperature, and, what is rathersurprising, the reverse action takes place only to a small extent..Similar results were obtained when solid ammonia a t -190° was99 Trans., 1910, 97, 1226.85 Atti R.Accad. Lincei, 1910, [v], 19, ii, 294 : A,, ii, 952.8G Trans., 1910, 97, 400.83 Covnpt. rend., 1910, 150, 1524 ; A ., ii, 707.Ibid., 1383 ; A . , ii, 607INORGANIC CHEMISTRY. 53treated with solid emanation, although the action naturally wasslow.Some new metallic nitrides have been prepared by Fischer andSchroterg7 by forming an arc between silver as the anode and themetal concerned as the cathode, the electrodes being immersed in aliquid mixture of 90 per cent. of argon and 10 per cent. of nitrogen.The rapid cooling of the liquefied gas serves to prevent the decom-position of the newly-formed compounds. The elements sodium,potassium, rubidium, cadmium, iridium, thallium, lead, arsenic,antimony, and tellurium were shown to give nitrides. They werein most cases not pure, but contained particles of disintegratedmetal. They are true nitrides, and not derivatives of azoimide.Gold, nickel, cobalt, and the platinum metals do not form nitridesunder the experimental conditions described.According to Raschig,88 hydrazine can be readily obtained fromhydrazine hydrate by treatment with solid sodium hydroxide.Equalquantities are heated together in a distilling flask very slowly to1 5 0 O . Anydrous hydrazine distils over as a, strongly fuming liquid,which is quite stable.The varieties of phosphorus have been a subject of much dis-cussion during the last two years, the chief point of dispute beingwhether red phosphorus and Hittorf’s phosphorus (obtained bycrystallisation from melted lead) are separate entities. Cohen andOlie8Q have asserted that from experiments on the specific gravity,heats of combustion, fusion and vapour pressure of various samplesof red phosphorus, only two varieties of phosphorus exist, namely,white phosphorus and Ilittorf’s so-called metallic phosphorus.Theyconsider that red phosphorhs is a solid solution of white phosphorusin the metallic variety. Stockgo points out that if this were true,the proportion of white phosphorus, as deduced from the specificgravities, would be as high as 30 per cent., and this is not inaccordance with its physical and chemical behaviour ; he regardsred phosphorus as a solid solution of several varieties of red phos-phorus in each other, and agrees with Cohen and Olie’s mainconclusion that white phosphorus and Hittorf’s phosphorus are theonly two modificatichs of this element.The same author, withGomolka,gl has made a careful preparation of Hittorf’s phosphorus,but finds, as all previous workers have found, that the purestproduct obtainable still contains 1.5 per cent. of lead. J0libois,~2on the other hand, maintains the view that red phosphorus is an87 Ber., 1910, 43, 1465 ; A., ii, 605.89 Chem. Weekblnd, 1909, 6, 821; A . , 1909, ii, 998.C h m . Zeit., 1910, 34, 254 ; A., ii, 288.91 Ber., 1909, 42, 4510 ; A . , ii, 30.g2 Comnpt. rend., 1910, 151, 382 ; A . , ii, 846.s8 Ibid., 1927 ; A, ii, 70654 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.individual modification, but asserts the existence of a third variety,which he terms pyromorphic. This was obtained by heating redphosphorus 93 in a vacuum to 360°, when its density increases from2'18 to 2.37.It must be pointed out, however, that such increases indensity of substances by heating are not at all uncommon, and donot necessarily indicate the formation of a new entity. On review-ing all the evidence, the writer has come to the conclusion that thework of Chapman,g* which showed that red phosphorus and Hittorf'sphosphorus were identical, still stands. Many of the researchesquoted above have been done with commercial red phosphorus,which, it should be noticed, always contains some yellow phosphorus.The writer is inclined to believe, from his own experiments, thatcarefully purified red phosphorus, when sealed up in a vacuum fora long time, undergoes a slow change to ordinary phosphorus, andthat this change, slow as it is, may account for some of thediscrepancies in the work of the authors who have investigated thesubject.A new chloride of phosphorus has been prepared by Besson andFournier 95 by submitting a mixture of phosphorus trichloride andhydrogen to the action of the silent electric discharge.A yellowsolid is formed at the same time. The liquid is fractionally distilledunder diminished pressure, and after purification it is found to havethe composition P,Cl,. It is easily oxidisable in air, taking firespontaneously in certain circumstances. With water, phosphorousacid and a yellow solid are produced.Perphosphoric acid has been studied by Schmidlin and Mas~ini.~*They show that electrolysis of phosphoric acid and its salts does notgive rise to higher oxidation products, neither does phosphoric acidreact with hydrogen peroxide.When, however, hydrogen peroxide(30 per cent.) is mixed wit'h either metaphosphoric acid or withphosphoric oxide at low temperatures, a liquid is obtained which hasstrong ox'idising properties. Manganese salts are even oxidised topermanganic acid by the liquid. The analysis points to the formulaPO(HO),*O*OH, so that the acid is tribasic. When pyrophosphoricacid in excess is treated with hydrogen peroxide, mother per-phosphoric acid, H4P,0,, is obtained in small. quantity.Group V11.The reaction of chlorine, dissolved in carbon tetrachloride, with alarge number of metallic oxides has been investigated by Michael93 Compt. rmd., 1909, 149, 287 ; A ., 1909, ii, 726.D4 Trans., 1899, 75, 734.gJ Compt. rend., 1910, 150, 112 ; A., ii, 1112,96 Ber., 1910, 43, 1162; A., ii, 498INORGANIC CHEMISTRY. 55and Murphy.97 At different temperatures most of the oxides react,producing chlorides. Ferrous oxide gives ferric oxide and ferricchloride even at -18O, whilst the similar reaction with cobaltousoxide only takes place at looo. Silver oxide reacts at the ordinarytemperature, giving silver chloriae and carbonyl chloride ; lithargegives lead dioxide and lead chloride at looo. The oxides ofmolybdenum, tungsten, and uranium are the most resistant,requiring temperatures of 225--280° to complete the reaction.Similar work has been done by Camboulives 98 with the vapour ofcarbon tetrachloride passed over the heated oxide at temperaturesbetween 2 1 8 O and 580O.I n general, the results were the same asthose of the American chemists. Boron trioxide and silica wereunaltered by the treatment, but a difference, of which one canscarcely overestimate the importance as regards mineral analysis,was noticed between the behaviour of free and combined silica.The latter alone is attacked, and a method is available for readilydistinguishing between these constituents of a mineral.Group V I .An important paper on the decomposition of ozone, by D. L.Chapman and H. E. Jones,m gives the results of heating ozone tolooo in presence of various other gases. It is shown that thepresence of oxygen, nitrogen, carbon dioxide, carbon monoxide, andprobably water vapour are without influence on the rate of decom-position.Nitrogen peroxide and chlorine very considerablyaccelerate the rate of decomposition. The influence of moisture wasfound to be practically nil. The experiments show that the changeis a bimolecular one. M. Beger1 has noticed that when ozone isdecomposed a t 350° a phosphorescent light is observable. Thisphosphorescence is much more marked if a hot glass rod be broughtnear the surface of liquid-ozone. Remsen and Southworth2 manyyears ago asserted that when ozone was decomposing in presence ofcarbon monoxide, no carbon dioxide was produced.maintains the contrary. He finds that the mixture of gases reactsstrongly in sunlight, and slowly in the dark, the carbon dioxideformed producing a copious precipitate when passed through bariumhydroxide solution.A new synthesis of Caro's acid is given by D'Ans and Friederi~h.~Chlorosulphonic acid is treated with the calculated quantity of97 Amer. Chem. J., 1910, 44, 365; A., ii, 1068.9% Compt. rend., 1910, 150, 175, 221 ; A., ii, 202.Zeitsch. E'lektmchem, 1910, 16, 76 ; A . , ii, 287.Compt. rend., 1910, 150, 1332; A., ii, 608.Clausmann9'3 Traits., 1910, 97, 2463.2 Ber., 1875, 8, 1414; Journ. Chem. SOL, 1876, i, 341.4 Ber., 1910, 43, 1880 ; A., ii, 706,56 -4NNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.100 per cent. hydrogen peroxide in a freezing mixture. Afterremoval of the hydrogen chloride in a vacuum, a crystalline maasis left, which melts about 45O, and is comparatively stable. If asecond molecule of chlorosulphonic acid be added t o the Caro's acid,persulphuric acid, H2S208, is obtained in crystals. This acid ismuch more stable than Caro's acid, and can be kept for months.Group VZIZ.Fischer and Hahnel5 have elaborated their apparatus for thepreparation of argon from air. An iron tube containing calciumcarbide serves to eliminate nitrogen and oxygen, and the carbonmonoxide is burnt by copper oxide, and carbon dioxide absorbedby potassium hydroxide. T'he gas is caused to circulate by amercury pump, and it was noticed that as the argon became morepure, the phosphorescence between the falling drops of mercury inthe pump became brighter, until at the end of the preparation itslight became visible in daylight. A similar effect was noticed byanother worker as given by helium, and as it was shown by Collie6last year to take place to a very marked extent with neon, thephenomenon is supposed by the authors to be characteristic of themonatomic gases.An easy method of obtaining argon is given by Claude.' Theordinary compressed oxygen of commerce is now very generallyobtained from liquid air, and contains about 3 per cent. of argon.When the oxygen is removed by heated copper, there remains verylittle nitrogen to be eliminated by magnesium. The method willbe of very great use to chemists who occasionally want a few cubiccentimetres of a gas more inert than nitrogen.The union of ferrous salts with nitric oxide 8 has been investigatedby Manchot and Huttner. They found that the volume absorbedwas diminished by the addition of small {'antities of sulphuric acid,but was increased by increasing the concentration of the sulphuricacid up to 82 per cent. This solution and those having a still higherconcentration of sulphuric acid are red in colour, and contain thecompound FeSO,*NO. It crystallises in small, red leaflets. Similarresults were obtained with a hydrochloric acid solution of ferrouschloride. The authors have drawn the conclusion that in no circum-stances is more nitric oxide absorbed than corresponds with onemolecule to one molecule of the ferrous salt.H. B. BAKER.Bcr., 1910, 43, 1435 ; A., ii, 608.6 Proc. Roy. Soc., 1909, 82, A, 378 ; A., 1909, ii, 668.7 Conipt. rend., 1910, 151, 752; A . , ii, 1061.8 Arinnlen, 1910, 872, 153 ; A., ii, 414

ISSN:0365-6217    

DOI:10.1039/AR9100700026

出版商:RSC    

年代:1910

数据来源: RSC

摘要:

ORGANIC CHEMISTRY.A STUDY of the investigations dealing wit'h organic chemistry whichhave been published during the last few years produces a vividimpression of the perfection that has been attained by the doctrinesof structural chemistry. The constitution of even the most complexcompounds may be attacked with the confidence that the solutionis dependent chiefly on experimental skill, and that unforeseentheoretical difficulties are unlikely to present themselves in thecourse of the investigation. A natural consequence of this state ofthings is that the majority of purely organic investigations proceedalong more or less conventional lines, and their chief interestJhenlies either in the practical value of the results obtained, or in theemployment of a new reagent, or of a new synthetical or analyticalmethod possessing intrinsic interest.I n other words, the structuralorganic chemistry of the present day is based on $he applicationof certain well-established principles to complex cases. How perfectthe adaptation of structural theory to experience has become isseen in stereochemistry, originally a daring extension of the con-ceptions of atomic linking which form the foundation of theoreticalorganic chemistry, but now an accepted doctrine, the conclusionsof which are verified in the most complete manner by experience.It is this very perfection of the hypotheses employed thattends to diminish the novelty of the results attainable in thefield of pure structural organic chemistry. To say this is not todepreciate the value of synthetical researches, or to deny theexistence of many unsolved problems of very great interest, but suchproblems refer rather t o difficult applications in special cases thanto fundamental principles.The opinion was expressed in last years report that the recentdevelopment of organic chemistry has been largely determined bythe influence of biology on the one hand, and of physics on theother.The same tendencies become more strongly marked everyyear. The problems connected with the chemistry of living matterare approached from two sides, the purely chemical and thephysiological, and although the two lines still remain separated bya considerable interval, their gradual convergence is clearly discern58 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.able.From the chemical side, slow but steady advances are beingmade, both by analytical and synthetical methods, especially in theimportant department of protein chemistry. Amongst compounds,the constitution of which is unknown, and to which methods ofdetermining structure have scarcely been applied, the enzymes areof primary importance. The study of their physico-chemicalbehaviour continues to make progress, but little advance has beenmade in the means of determining their homogeneity or of isolatingdefinite chemical individuals in this class of substances. The ques-tion of the presence of minute quantities of certain metals asessential constituents, particularly of manganese in the oxydases,has a special interest in view of the known influence of traces ofmetals in bringing about syntheses at the ordinary temperature,such, for instance, as the effect of iron salts in Fenton’s researches.The presence of iron as an essential component of haemoglobin, andof magnesium in chlorophyll, gives some indication of the importancethat this question, of the part played by metallic atoms in com-pounds capable of exercising a ‘‘ catalytic ” influence in physiologicalchanges, is likely to attain.The manner in which such atoms arelinked to the remainder of the molecule presents certain difficulties,referred to below, which have not yet received a satisfactoryexplanation. An allied field of research, the connexion between thephysiological activity of compounds and their chemical constitution,attracts much attention, which, however, has not yet succeeded indispelling the obscurity that surrounds it.Turning to the side of organic chemistry most influenced byphysics, we find that the energies of investigators are increasinglydirected towards the elucidation of the relations between thephysical properties of compounds and the structure of the moleculeswhich compose them.Such researches have a twofold aim. Onthe one hand, it is sought to establish relations of this kind as ameans of determining constitution in cases in which it is unknown,whilst, on the other, it is desired to represent the sum of theproperties of any given substance as a consequence of the arrange-ment and linking of the atoms composing its molecule.It is theattention devoted to these aspects of organic chemistry that hascompelled the renewed consideration of the validity of those con-ceptions which prove so satisfactory as long as only structuralquestions are involved. This is particularly noticeable in respectto the conception of valency. Whilst, from the purely syntheticalpoint of view, the accepted valencies of the elements only rarelypresent any obstacle to the determination of structure (the quadri-valency of oxygen, the tervalency of iodine, etc., under certainconditions being accepted without question by almost all chemists)ORGANIC CHEMISTRY, 59the case is altered when the object sought is the explanation ofphysical properties or of chemical reactivity.The fact that anatom or group of atoms may influence the properties of an atomwith which it is not immediately linked is not indicated by theconventional structural formulae. The conception of ‘ I residualaffinity,” or of a capacity for addition possessed by a molecule orradicle after the ordinary valencies of the component atoms havebeen apparently satisfied, is playing a most important part in thesemore recent developments of the science. Thiele’s views as to thedistribution of affinity in unsaturated molecules have provedexceedingly fruitful, and the assumption that the attractive powerof an atom is divisible to a greater extent than is implied by thevalency assigned to it is more and more generally employed. Thestatement in last year’s report (p.57), that the distribution ofresidual affnity in the molecule, with all that it implies, is thecentral problem of organic chemistry at the present time,” maybe repeated in view of the tendency apparent in the most recentwork.It must be admitted that the conception of partial valency isat present tentative and vague, and it is not possible to form avery distinct physical idea of the condition implied, but this defectis inevitable for a time, and need not hinder its application. Thehypothesis is to be tested by its practical usefulness rather than byits consistency with any particular view as to the physical natureof chemical affinity.Another aspect of the problem of valency is presented by theattempt to correlate chemical constitution, crystalline form, andphysical properties by means of Pope and Barlow’s doctrine ofvalency volumes, the extension of which to different classes oforganic compounds is proceeding rapidly. This is a most interest-ing instance of a hypothesis on trial, and its possibilities ofdevelopment appear to be considerable.The study of a recent careful compilation of the relations betweenthe physical properties and the chemical constitution of organiccompounds1 shows very clearly the limited extent to which suchrelations have been established, and the vast field that yet remainsto be explored.Minor relations, valid only within the limits of acertain group of substances, abound, but important generalisations,worthy of being called laws, are conspicuously rare.I n this con-nexion, it is of interest to observe that several important papers haveappeared recently, in which the relations obtained by formerworkers, particularly in regard to refractivity and to the thernio-S. Smiles, Relations between Chemical Goastilulion and Some Physical Properties,London, 191060 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.chemical constants, have been subjected to revision in the light ofmor0 recent data.A department of chemistry which has received a remarkableamount of attention in recent years is that dealing with colloidalsubstances, and a glance through the pages of the important journaldevoted entirely to this subject makes evident the fact that the mostdiverse branches of chemical investigation are being profoundlyinfluenced by the stuay of colloids. This influence is either direct,as in the chemistry of vital products and of dyes and tanningmaterials, or indirect, as in the introduction of colloids, or mixturesof colloids, as ‘‘ catalytic ” agents for the purpose of bringing aboutor accelerating chemical reactions.The latter application is on theincrease, and presents a special interest from the possibility thusafforded of bringing about chemical changes at the ordinary tem-perature and in the absence of acids, bases, or energetic condensingagents. I n this way, by approaching more nearly to the conditionsexisting in the living organism, a partial bridging over of the gapbetween the synthetical processes of the laboratory and of theorganism becomes possible.As in previous years, it has been necessary to make a selection,for the purpose of this report, from the papers abstracted duringthe year, and the endeavour has been made to give special attentionto investigations bearing on the general questions alluded to above.Amongst special problems, the knowledge of the terpenes has beenadded to in several important respects, and further advances havebeen made in the investigation of many alkaloids and otherriaturally occurring substances. Much of interest has also arisenfrom the study of organic compounds containing sulphur, theinfluence of this element in modifying the properties of organiccompounds in which it occurs being sometimes very remarkable.The Theory of Chemical Reactions.Investigations having for their object the elucidation of themechanism of reactions of carbon compounds continue to yieldinteresting and important results, but it cannot be said that anystriking advances have been made during the year, and with oneor two exceptions no theoretical suggestions of a novel or stimulatingcharacter have been made.Interest can no longer attach in anydegree to sweeping generalisations in favour of purely ionic or purelynon-ionic theories of any type of reaction in carbon compounds,although even now experienced workers in the subject are notalways averse from making such one-sided pronouncements. I nsome cases, the evidence strongly supports an ionic explarlation,and in others the reverse obtains, and all who have considered thesORGANIC CHEMISTRY.61matters with an open mind are fully alive to the changes whichmay be rung on these possibilities. While the electrolytic dis-sociation hypothesis pictured the ions as chemically free atoms orgroups, it offered an attractively simple explanation of manyobservations, but with the growing recognition that ions ih solutionare probably united chemically as well as electrically with thesolvent, the simplicity has disappeared, and there is little except theinfluence of electrical charges to distinguish reactions of ionsfrom those of other molecules. Much the same is true of the vexedquestion of intramolecular versus intermolecular migrations of atomsor groups; and until some entirely novel conception appears, theresimply remains the test of experiment t o decide between a varietyof obvious alternatives in each special case.I n last year’s report, reference was made t o the work which isbeing done by Goldschmidt, Orton, Titherley, Auwers, and othersin this department of organic chemistry, and their contributionsduring the year 1910 include much that will find a permanent, placein the literature, although the results cannot again be dealt within detail here.Other communications from the laboratories of theJohns Hopkins University afford evidence that organised andstrenuous efforts are being made to solve some of the outstandingproblems connected with tautomerism and reaction mechanism ingeneral, and important advances in the near future may confidentlybe anticipated.The most interesting theoretical communication isprobably that which appears from the pen of one of the pioneersin this region, some of the fruits of whose experience and thoughthave been assimilated almost unconsciously by the younger schoolof organic chemists, and may almost be said to form part oftheir theoretical system. The appearance of the thesis entitled“ A n Outline of a Theory of Organic Chemistry founded on theLaw of Entropy ” 3 must therefore be regarded as an interestingevent. This paper deserves careful study as representing the matureviews which this ingenious worker has formed after many years ofthought concentrated upon the nature of the reactions of organiccompounds. Possibly it might prove dangerous to the peace of mindof a student imperfeetly grounded in the principles of thermo-dynamics, for the familiar terms of the latter science are here putto unorthodox uses.The author postulates the principle that a chemical system willalways change in such a way that on the whole the greatest increaseS. Nirdlinger and S.F. Acree, Amer. Chem. J., 1910, 43, 358; 44, 219;8. Nirdlinger, E. K. Marshall: and S. F. Acree, ibid., 358 ; E. E. Reid, ibid., 489 ;R. F. Brunel and S. F. Acree, ibid., 505 ; A., i, 341, 785, 444, 481, 520.Michael, J. Amer. Chew. Soc., 1910, 32, 990 ; compare also, ibid., p. 322, andBer., 1910, 43, 621 ; A., i, 28562 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in entropy occurs unless such a consummation is opposed by somechemical hindrance.This principle cannot be disputed, and thedifficulties only arise in its application, but from this communicationit may be gathered that by careful classification of data the relativefree chemical energies associated with the molecules of isomericcompounds may be roughly gauged, and certain broadgeneralisations then reveal themselves. As a*n aid to suchestimations, the elements are, as usual, assumed to be endowedwith positive or negative elegtrical characters of varying degreesof intensity, and the accurate attainment of an electrical balancebetween the atoms in the molecule is regarded as a factor in theinternal “ neutralisation ” or low content of molecular free energy,and inversely; the results may then be used in predicting thechanges likely to occur in new combinations of circumstances.Itwas t o be expected, however, that the originator of a system ofchemistry based on the second law of thermodynamics would justifyremarks such as the following (which refers to the alkylation ofethyl acetoacetate) : “ as the heat of formation of the C- is greaterthan that of the 0-methyl derivative, its formation represents themaximum entropy of the system.”4 I f this does not represent itmere reversion to the doctrine of Thomsen and Berthelot, itmay be surmised that the author, in the course of the thermo-chemical investigations which are in progress under his direction,has obtained a sufficiently large number of data to show that whenisodynamic isomerides are compared, the individual which atequilibrium is present in smaller amount has the greater heat ofcombustion in all cases.I f this be so, it most important stepforward has been made, and it will be possible t o extend very greatlythe application of thermochemical data to theoretical organicchemistry; it is worthy of note that such a generalisation certainlyappears to be foreshadowed by the recent investigations of Auwersand his pupils, which are referred to elsewhere (p. 69). Attentionshould be drawn t o the fact that “chemical hindrance,” in thesense used in the above thesis, is not synonymous with ‘(sterichindrance.” The former is imagined as a resistance t o a givenincrease in entropy; the latter, which is less definite, has been usedto include much that might be classified under the formerheading, but is also frequently applied to express the fact that asmall change in a system corresponds with the attainment ofmaximum entropy, in such cases as this effect is traceable to theinfluence of certain atoms or groups in the neighbourhood of thereactive portion of a molecule. Thus the difficulty in replacing thehydrogen atom in methane by chlorine is attributable to ‘( chemicalLOC.cit., p. 1003ORGANIC CHEMlSTKY. 63hindrance '' ; t,he difficulty in converting dimethylmaleic anhydrideinto the acid is said to'be due to " steric hindrance,?' and is ratherthe result of the instability of the acid caused by the methyl groupsthan a low velocity of hydration due to chemical hindrance.Thelow esterification velocities of certain oo-disubstituted benzoic acidsappear to represent cases of chemical hindrance, although it is stillan open question whether this hindrance is due to true stericinfluences. These questions have been dealt with at length by otherchemists, and the subject must be studied from every point of view.6The hypothesis advanced by Stieglitz in explanation of theHofmann change of bromoamides and of the Beckmann change ofoximes, assumed that at an intermediate stage there is formed acompound which contains a univalent nitrogen atom. Schroeterhas recently adopted this view,6 the details of his interpretation ofthat hypothesis in its application to oxime transformation beingexpressed by the following scheme :R,R,C:NOH -% R,R,C<" H -+ R,R,C'<z -+ RIC<:B,."<OHThis proposition, which was approved by Stieglitz,7 has beensubjected to effective criticism on the ground that it is not con-sistent with what is known of the behaviour of the isomeric pairs ofoximes formed by unsymmetrical ketones.The hydrogen chlorideadditive products from one member of a pair would be identicalwith those from the other, and the same would therefore applyto the final transformation products; it is inferred that the centralidea of Stieglitz's explanation is not tenable.*Studies of the influence of experimental conditions on the modeof chlorination of toluene have yielded results which will doubtlessprove of great value in subsequent discussions on the mechanism ofsubstitution processes in aromatic compounds. On determining theproportion of side-chain substitution products to nuclear substitutionproducts, it was found that access of light raised the proportionfrom 16 to 60 per cent.when concentrated aqueous hydrochloric acidwas in contact with the toluene; if moist gas was passed into toluenealone, the proportion was about 60 per cent., rising to 90 per cent.in presence of light; with dry gas in the dark, the proportion was90 per cent., in which case, naturally? light caused a relativelysmall rise in the ratio. The distribution of the chlorine in theproducts obtained in the dark was largely dependent on the amountof water present'; in the complete absence of moisture, the proportionof benzyl chloride rose to 90 per cent., whilst 62 per cent.wasCompare B. Fliirsclieim, Tmns., 1910, 97, 84, and Ann. Report, 1909, 58.Ber., '1909, 42, 2336 ; A . , 1909, i, 617.7 Ibid., 1910, 43, i 8 4 ; A., i, 323. 8 P. J. Montagne, ibid., 2014 ; A., i, 62364 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.obtained when moist gases were used,.and only 16 per cent. when allthe materials were saturated with moisture; in all cases the chlorineused was obtained by electrolysing hydrochloric acid. Incidentally,itl was observed that when moist chlorine is passed into boilingtoluene in the light, the hydrocarbon gradually assumes a yellowcolour, which it retains after washing; this colour is removed whenhydrogen chloride is introduced in the light, reappearing when thesupply of this gas is cut 0ff.QThe velocity of hydration of acid anhydrides in aqueous solutionhas been determined by measuring the conductivity of the solutionat intervals, and calculating the corresponding amounts of freeacid, the necessary allowance for the variation of the properties ofthe medium being determined by subsidiary viscosity measurements.The reaction is nearly of the unimolecular type when small con-centrations of anhydride were employed, and the results obtainedindicate that the reaction is not accelerated by the presence ofhydrogen ions.No reference is made t o the well-known effect ofsmall quantities of sulphuric and other powerful acids in acceleratingacetylation of water, hydroxy-compounds, and weak bases, withacetic anhydride.10It appears probable that acetylation by anhydrides, like esterifi-cation by the free acids, may proceed by either or both of two paths,one which is brought about or accelerated by the agency of a“ catalyst,” and the other which may be termed automatic; theformer would probably be more evident in indifferent non-aqueousmedia.The interaction between silver nitrate and a-halogen derivativesof fatty acids (or their sodium salts) is much accelerated by thepresence of small quantities of silver bromide or iodide; silveriodide also exerts a similar influence on the speed of the reactionbetween silver nitrate and methyl iodide, and this effect is probablyconnected with the tendency of the silver halogsn salts to persistin a colloidal condition.The most satisfactory explanation of thequantitative results obtained in this investigation is that the mainreaction between the halogen-substituted acids and silver salts isone taking place between the Ag’ ions and the anions of the organicacid, which is consistent with the view that the electrical attractionsor repulsions between ions with opposite or like changes may greatlyinfluence reaction velocities.11In this communication, attention is also drawn to a retardinginfluence exerted in the case of halogen-substituted acids by thenitric acid formed, an effect also produced by the addition ofJ. R. Cohen, H. M. Dawson, J. R. Blockey, and A. U’oodmansey, Trans., 1910,G. Senter, ibid., 346 ; compare Ann.Report, 1909, 70.97, 1623. lo A. C. D. Rivett and N. V. Sidgwick, ibid., 732, 1667ORGANIC CHEMISTRY, 65benzenesulphonic acid or, to a much smaller extent, lactic acid;thus the reactions between silver salts and organic halogen com-pounds are complicated by a variety of disturbing side effects, aswas indicated by the previous work of Burke and Donnan and otherinvestigators. I n continuation of researches on the reactionbetween silver salts and alkyl haloids, it was observed that using assolvent the filtered liquid from a previous experiment, free fromsilver salt or alkyl iodide, the change proceeded more rapidly thanwith the original solvent, and to an extents which accounted for theabnormalities noted in the earlier experiments of Burke andDonnan ; a number of interesting observations are also recorded,some of which cannot yet be satisfact*orily explained.12The so-called catalytic influence of acids and bases on numerousreactions has been generally associated with their affinity constants,and discrepancies in the expected order of their activities havefrequently been traced to a variation of their affinity coefficientswith the nature of the medium in which they may be dissolved.Since Knoevenagel’s discovery that in certain cases tertiary bases,however powerful, are relatively inefficient as ‘( catalysts,” it becameevident that some specific action occurs in many cases, and theinfluence of primary and secondary bases has been explained byarguing that these form additive products in this manner, whichX +is impossible in the case of tertiary bases, and tYlese additive productsare assumed to be much more reactive than the original compound,although in many cases no very obvious reason for this appears.Reactions similar to those brought about by bases such aspiperidine are also observed with certain aminoiacids, peptones,proteoses, or even proteins ; thus, for instance, furfuraldehyde doesnot condense with malonic acid, but does so in presence of glycineor alanine.The observation suggests that such nitrogenous com-pounds may be effective as (‘ catalysts ” in certain processes occurringin the living cell.13Most interesting evidence corroborating the view that bases mayexert a specific ‘I catalytic ” influence has been obtained with theaid of optically active compounds.Bases greatly accelerate thedecomposition of camphorcarboxylic acid by heat into carbondioxide and camphor, and it is now found that the Z-camphor-carboxylic acid decomposes 46 per cent. faster than the d-acid inpresence of quinine, and the &acid 46 per cent. faster than the Z-acidin presence of quinidine ; consequently, when inactive camphor-l2 F. G. Donnan and H. E. Potts, Tram., 1910, 97, 1882.l3 H. D. Dakiu, J. Bid. Chcm,, 1909, 7, 49 j A , , i, 101.REP.-VOL. VII. 66 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.carboxylic acid is partly decomposed in presence of quinine, thecamphor formed is slightly lzvorotatory, and the remaining acidslightly dextrorotatory. The results obviously have an importantbearing on the question of the mechanism of the specific actions ofenzymes and of asymmetric synthesis byAn interesting photo-chemical reaction is the conversion, inindifferent solvents, of o-nitrobenzaldehyde into o-nitrosobenzoicacid, whilst in alcoholic solution an ester of this acid is produced.The latter reaction is remarkable, as the acid is not esterified ifdissolved in an alcohol and exposed to light.The chance observationthat o-nitrobenzaldehydediethylacetal is converted into ethylo-nitrosobenzoate by light gave the explanation of the reaction,which evidently takes place in t,he following stages :NO,-C,H,*CHO -+ NO*C,H,*CH(OEt), +catalytic ” action.14[NO*C,H;C(OEt),-OH] + NO*C,H,*CO,Et + Et00H.l~The results of experiments with compounds containing varioussubstituents, and with different alcohols, are considered to favourHenry’s view of the esterification of an acid, namely, that the mono-alkylated ortho-acid appears as an intermediate product, thus :*C<gH R’oH -+ [ %-OH <I:] -+ *C<ER+H,Oand a similar scheme is proposed for the etherification of phenols.The chemistry of phototropic changes remains, however, veryobscure. The examination and comparison of a large number ofhydrazones and osazones has failed to reveal any relation betweenconstitution and liability to undergo phototropic change, especiallyamongst the osazones, although a few minor regularities have beendetected in other groups.l7 Again, whilst light usually brings aboutthe conversion of labile ethylene derivatives into their stable stereo-isomerides, the reverse change into the labile modification under theinfluence of ultra-violet light occurs in the coumaric acid series.18The Influence of Unsaturation.A great variety of work might be grouped under this heading,numerous investigations having dealt with the effect produced oneither the physical or the chemical properties of compounds by thestate of unsaturation of the molecule.The first place may begiven to the influence on certain physical properties, namely,14 K. Fajans, Zeitseh. physikal. Chern., 1910, 73, 26 ; A . , ii, 599.l5 E. Bamberger and F. Elger, Aiznnleiz, 1910, 371, 319 ; A . , i, 267.F. Graziani, Atti R. Accad. Lincei, 1910, [v], 19, ii, 190 ; BI.Padoa and F.Graziani, ibid., 193 ; B L Padoa and L, Santi, ibid., 302 ; A., i, 777, 778, 779.L8 R. Stoermer, BET., 1909, 42, 4865 ; A., i, 124ORGANIC CHEMISTRY. 67refractivity and dispersive power, heat of combustion, and magneticsusceptibility. Short accounts of some chemical methods of study-ing unsaturation, and of some of its effects on reactivity then follow,whilst other matter relating to unsaturation is to be found in thesection on colour and constitution, and elsewhere.Physic& Properties.-The refractivity of an organic compoundis intimately related to the number and arrangement of the doublelinkings in the molecule, and measurements of refractivity havetherefore rendered most important services in the determination ofconstitution, especially in the terpene series.In such cases, therelations employed are those originally found by Briihl. Apparentexceptions have been observed from time to time, and an extendedinvestigation has now been undertaken,lg with the object of removingsuch anomalies. It is found that the existence of optical exaltationdue to unsaturation is best determined by comparing specific, andnot molecular, refractivities and dispersive powers. [Under theseconditions, a few apparent anomalies, due merely to the multi-plication of small errors, disappear.Only two classes of compounds have been observed to exhibitmarked optical exaltation without the presence of conjugated doublelinkings. These are t h s methene derivatives, \:C<, containinga semicyclic ethylene linking, and compounds containing a ring ofthree carbon atoms, the conjugation of the latter system with adouble linking giving a remarkably great exaltation.A number ofinstances in which an expected exaltation does not occur areexplained by the disturbing influence of side-chains attached to thecentral carbon atoms of a conjugated system. Thus the exaltationdiminishes in the series:--/or in the series:the chemica.1 nature of the substituent having an influence on theamount of the depression. If further substit'ution takes place, sothat side-chains are attached to the terminal as well as to the centralatoms of such a system, the exaltation is further diminished, prac-19 K. Auwers and F. Eisenlohr, Ber., 1910, 43, 806, 827 ; J.pr. Chem., 1910,[ii], 82, 65 ; A . , ii, 365, 367.F 68 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.*c=c-c:o *c=c-c=ctically vanishing in such systems as k and 6, R fySystems containing Thiele’s ‘‘ crossed double linkings ” showexaltation, but in a less degree than in normal chains. Repeatedconjugation in a straight chain gives very high exaltation. Theformation of a ring has the same effect as the introduction of side-chains ; thus the systems Ig>C*C:CH and $X7*C:O resembleR itCH : C- C CHMe RCH : C-C: 0respectively.Me R andThe dispersive power is a more sensitive test for conjugation thanthe refractivity, often showing a distinct exaltation when nothingof the kind is observable in the latter property.By comparing together a number of pairs of compounds, thesecond member of which differs from the first by the substitutionof CH, for GO, such as:Formaldehyde, C E3,:CO Acetone, CMe2:C0Ethylene, CH,:CH, isoButylene, CMe,:CH, ’it is found20 that the increase of refractivity thereby produced ispractically constant, provided that only terminal groups are thusinterchanged.Much greater differences are observed when thesubstitution of a ketonic for an ethenoid linking occurs in themiddle of a chain, as in the pair:Stilbene, Ph*CH:CH*PhBenzophenone, P h O P h ..0Auwers and Eisenlohr’s conclusion, based on a very small numberof observations, that alkyloxy-groups reduce the exaltation morethan either alkyl or hydroxy-groups, is disp,uted on the ground ofa comparison of the refractivities of a number of aldehydes with thecorresponding methyl ketones, the differences being practically thesame for unsaturated as for saturated compounds.A furtherapplication of the method is made to determine the constitution ofseveral P-diketones, the results obtained being consistent with theother known properties of these compounds.The change in constitution which accompanies the formation ofsalts from a pseudo-acid may also be followed by means of thechange of refractivity.21 A considerable exaltation is observed20 Miss I. Smedley, Tmns., 1910, 97, 1475, 1484.21 A. Hautzsch and K. Meisenburg, Bcr., 1910, 43, 95 ; A , , ii, 189ORGANIC CHEMISTRY. 69during salt-formation, even when the original substance is trulyenolic, thus suggesting that subsidiary valencies are concerned inthe production of wci-salts (see p.SO). The change does not runentirely parallel with that of colour; thus, it is greater on passingfrom pnitrophenols to their salts than in the more highly colouredortho-series. The exaltation on forming a salt of such a substanceas ethyl acetoacetate is greater than when alkyl or acyl derivative2are formed.The effect of unsaturation on the heat of combustion has alsobeen studied and brought into relation with the optical properties.22Many of the data existing in the literature are not comparable,owing to the comparative roughness of the thermochemical niethodsemployed, but the improved forms of calorimetric bombs admitof an accuracy of 0.05 per cent., and results thus obtained havea high value in the determination of constitution. The more labileof a pair of isomerides has the higher heat of combustion.Hydro-carbons with conjugated double linkings always have a lower heatof combustion than their non-conjugated isomerides, and are thusto be regarded as more saturated, whilst the addition of side-chainsto a conjugated system diminishes the effect. Generally, the thermo-chemical method is less convenient in its application than theoptical, but it occasionally furnishes evidence of conjugation whenoptical methods fail, as in the case of phellandrene. It fails, how-ever, with bicyclic terpenes.The magnetic susceptibility of an organic compound may alsobe separated into two parts, one of which represents the sum ofthe atomic susceptibilities, whilst the other depends on the dis-tribution of atomic linkings in the m0lecule.~3 Values of the latterhave been determined for a number of different types ( inking, andthe method has been applied to the determination of structure.Amcompounds and hydrazones, for example, give widely differentvalues for the susceptibility, and a further means is thus providedof distinguishing between the two alternative structures. Thecolourless modifications of p-azoanisole and p-azophenetole, examinedin this way, behave like azcwompounds, whilst the coloured modifi-cations obtained from them by the action of heat give valuescorresponding with the hydrazone formula.Chemical Properties.-A re-examination of Thiele's work on con-jugated linkings has been undertaken by Borsche,24 and the attempthm been made to determine, with greater precision, the distributionK.Auwers and W. A. Roth, Ber., 1910, 43,1063 ; Annalen, 1910, 373, 239 ;K. Auwers, M'. A. Roth, and F. Eisenlohr, ibid., 267 ; A., ii, 485, 585, 586.W P. Pascal, Compt. rend., 1910, 150, 1167 ; A., ii, 580.24 W. Borsche, Annalen, 1910, 375, 145 ; A., i, 68070 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of residual affinity in molecules containing conjugated and crosseddouble linkings. The paper is too long to analyse a t all fully, andthe conclusions do not in any way invalidate the brilliant work ofThiele, but the latter is supplemented in several respects.Theexperimental part of the research consists chiefly of reactionsbet8ween ethyl acetoacetate and compounds containing ths system ofcrossed double linkings, . I f the chain of atoms issufficiently long, the ends may approach one another so closely thata part of the residual affinity is saturated, and in accordance withthis supposition it is found that ethyl acetoacetate combines withdistyryl ketone (I), but not with dicinnamylideneacetone (11) :c: c*c* c:o0CHPh CHPhHC 0.' CH\ I:& HC C CHbHPh CHPhI1 I1// ..., /.I' y..(I 1 1 I) CHO Uc \A\/ CH CH(1.1 (11.)Unsaturated open-chain acids having a double linking in theafl-position are conjugated, whilst their By- and other isomerides arenot conjugated. The latter therefore show the more unsaturatedcharacter, and it is found25 that the addition of bromine to themoccurs so much more rapidly than in the former case that thedifference of velocity may be employed as a method of distinguishingbetween the isomerides.Auwers also finds that the heat of com-bustion of afl-unsat<urated acids is less than that of acids in whichthe double linking is in the fly-position.The researches which have been carried out during the last fiveyears by Harries and others, dealing with the action of ozone onunsaturated compounds, have been summarised recently,26 withthe addition of some further material. The reaction is a valuableone for the recognition of unsaturated groups, and for distinguishingconjugated from unconjugated double linkings, but in certaininstances its: indications are ambiguous. The ozone reaction withbenzene derivatives, for example, has not been generally acceptedas proving the existence of ethylene linkings in benzene.Suchlinkings are indicated as absent from the methylated benzenes whenthe test of oxidation by air in presence of powdered sodium hydroxideis applied, although this test is usually capable of detecting doublelinkings.2725 J. J. Sudhorough and J. Thomas, Trans., 1910, 97, 715.26 C . D. Harries, Annnlen, 1910, 374, 288 ; A., i, 607.%' K. W. Charitschkog, J, Buss. Phys. Chewz. Soc,, 1909, 411, 1152 ; A , , i, 104ORUANIC CHEMISTRY. 71The addition of hydroxylamine to unsaturated compounds takesplace only when the ethylene linking is suitably conjugated, andmay be almost entirely prevented by the introduction of certaingroups.28 Thus, in the series :Sorbic acid, CHMe:CH*CH:CH*CO,H.Piperic acid, CH,<O>C,H,* 0 CH CH* CH: C K*CO,H.a-Phenylci nnamenylacr ylic acid, CHPh: CH-C H : CP h* C0,H.the first takes up hydroxylamine in the cold, the second and thirdonly slowly on heating.Grignard's reagent also finds frequent application in the studyof unsaturated linkings.Compounds containing the chain C:C*C:O,such as phenyl styryl ketone, give only saturated compounds withGrignard's reagent, but react with zinc or magnesium and methylbromoacetate t o form unsaturated compounds, such as methyl/3-hydroxy-/36-diphenyl-Ay-pentenoateyCHPh:CH*CPh( OII)*CH,*CO,Me,by addition in the a/3-position.29Reactivity.-A series of measurements of the rate of hydration ofacid anhydrides brings out incidentally the effect of conjugateddouble linkings on the velocity.Thus, whilst the constants foracetic and succinic anhydrides are practically the same, that formaleic anhydride (I) is ten times as great, whilst itaconic anhydride(11) exhibits only a slight increase $0 :The system C:C:C, in which the double linkings are adjacent,possesses very high residual affinity, and allene compounds arecorrespondingly difficult to prepare. It might be expected thatthe system C:c"*C:C:C would be intermediate in stability betweenan allene derivative and a conjugate6 compound. As an aromaticnucleus or a carbonyl group, attached t-o .C:c'*, has the same effectas another ethylene linking, it might be expected that a compoundx>C:C:C<F Y would be stable if X, Y, W, and Z were all28 T.Posner and K. Rohde, Ber., 1910, 43, 2665 ; A., i, 847E. P. Kohler and G . L. Heritage, Amer. Chem. J., 1910, 43, 475; E. P,Kohler and If. C. Buruley, ibid., 412 : A , , i, 484, 891.90 A, C, D. Kivett arid N. V. Sidgwick, Trans., 1910, 97, 167772 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.aromatic residues or carboxyl groups.31 An attempt to preparec10H7>C:C:C<$$& led to an indecisive result, but the compoundis probably stable, as is tetraphenylallene.Another test of the reactivity of unsaturated compounds of thetype X=CH2=R, in which X is a halogen atom, is afforded byexperiments in which these compounds are brought into contactwith pyridine in alcoholic solution.The reactivity of X is thenconditioned by the residual affinity of R, in the manner describedin last year’s report (p. 59). When the residual affinity is reducedby conjugation, the reactivity is also reduced. Thus, cinnamylbromide, Ph*CH:CH*CH,Br, in which the double linking is con-jugated with a phenyl group, has less than one-half the reactivityof ally1 bromide, CH,:CH*CH2Br. I n agreement with the resultsobtained by other methods, the residual affinity of the carbonylgroup in ketones is found to be greater than that of carboxyl,indicating some affinity between the two oxygen atoms of thecarboxyl group. I n a phenyl ester, the phenyl absorbs much ofthe residual affinity of the hydroxylic oxygen, and the second oxygenatom thereby becomes more ketonic, so that the reactivity of theC6H50 bromine atom in phenyl bromoacetate, CH,Br*C<oph, is againincreased.32g e t e r r Compounds.-As an appendix to the subject ofunsaturation, some notes may be collected, dealing with two classesof compounds which derive their chief interest from their connexionwith this subject, namely, the derivatives of keten and of triphenyl-methyl.Keten is conveniently prepared, when required as a reagent, bypassing acetone vapour through a tube packed with fireclay at500-600° : CH,-CO*CH, = CH,:CO + CH4.33 Combination withhydrogen cyanide takes place to form a compound, C,H,O,N, whichboils at 1 7 3 O , but nevertheless reacts as if it were a mere mixtureof its components.The formula CH,:C(OAc).CN is proposedt e n t a t i ~ e l y . ~ ~ It is now agreed35 that the so-called acetylketen iscyclobutan-1 : 3-dione.The formation of bases from dimethylketen by tertiary bases hasalso received further study, combination being found to take placethrough the C:N- linking. The formula (I) is now proposed for3l A. Lapworth and E. Wechsler, Tram., 1910, 97, 38.ya H. T. Clarke, ibid., 416.33 J. Schmidlin and M. Bergmann, Ber., 1910, 43, 2821 ; A., i, 816.34 Miss S. Deakin and N. T. M. Wilsmore, Trans., 1910, 97, 1968.35 Miss F. Chick and N. T. M. WiIsmore, ibid., 1978ORGANIC CHEMISTRY. 73dimethylketenquinoline, and the formula (11) for the compoundwith acridine 36 :(1.1 (11.1Compounds of the Tripheny Zmet h yl Group.-Several additionshave been made to our knowledge of t,his interesting group of com-pounds.An analogue of triphenylmethyl has been found, whichexists in solution entirely in the unimolecular condition. This istridiphenylmethyl, (C,H,*C,H,),C=, which forms deep violet solu-tions, green in thin layers. The solutions of its haloid compoundsin liquid sulphur dioxide are coloured and conducting, and a whiteperoxide is very readily formed.37 The authors retain for thepresent Gomberg's original formula, R,C, rather than any of themodifications proposed.I n contrast with this compound, one in which the diphenyleneresidue takes the place of two diphenyl groups exists only in thebimolecular form, c6 K,.c'gH4*c------ C*C6H4*C6H5, which is cdour-/\ /\C6H,*C6H4 C6H,*C6K,less, and yields only colourless haloid compounds.38A third compound, ~GH4>CPh*CPh<~sK, forms colourlessC,H4 C6H4'solutions in benzene, which become coloured on heating, losing theircolour again when cooled, so that dissociation may be suspected.39When diphenyl takes the place of phenyl, there is no change ofcolour on heating. Triphenyltrimethylethane, CPh,*CMe,, behavesas a perfectly saturated hydrocarbon.The connexion between the appearance of colour and of electrolyticconductivity in solutions of the haloid compounds of this class isless close than was supposed, as triphenylmethyl bromide dissolvesin acetone, acetonitrile, and pyridine, and the solutions are colour-less, and nevertheless conduct electrolytically.The conductivity ofsolutions in the last-named solvent gradually falls, owing to theformation of triphenylmethylpyridinium bromide.40Tetr ap henyle t h y lene, CP h, : CP h,, be haves somewhat anomalously,being able to take up chlorine, but not bromine or iodine. The36 H. Staudinger, H. W. Klever, aiidP. Kober, Annabn, 1910,374,l; A, i, 586.37 W. Schlenk, T. U'eickel, and A. Herzenstein, ibid., 372, 1 ; A., i, 236.38 W. Schlenk and A. Herzenstein, ibid., 21 ; A . , i, 237.39 W. Schlenk, A. Herzenstein, and T. Weickel, Ber., 1910,43, 1753 ; A . , i, 469.40 A. Hantzsch and K. 13. Meyer, ibzd., 336 ; A . , i, 23874 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.dichloride, treated with benzene and aluminium chloride, does notyield a further phenylated derivative, but undergoes a remarkablecondensation to 9 : 10-diphenylphenanthrene :PhC--ICPhDiphenylene-ethylene, YGH4>C: C < p z 4 , another member ofCtiH4 G 4this remarkable series of hydrocarbons, has a deep red colo~r.*~Colowr and Constitution.Last year's report (p. 64) referred to the attention given tocoloured compounds of t h s quinhydrone class.The number ofhighly coloured additive compounds has again been very largelyincreased. In addition to the familiar quinhydrones, or additivecompounds of quinones and dihydric phenols, many quinonescombine with other phenols, yielding darker coloured products. Onthe other hand, aliphatic ketones, even if coloured, do not yielddarker products with phenols.43 The oxygen of the quinone is notessential, as quinone-chloroimide and -dichloroimide, O:C,H,:NCland ClN:C6H4:NCl, form exactly similar quinhydrones withquinol.44 When pbenzoquinone is brought into contact with tri-phenylmethyl, the first product is an unstable, orange additive/-\compound, CPh,--.-,O:/ \:O-----CPb,, which, however, soon passes \-/into the very stable trisenylmethyl ether of quinol,C P h ,* O/-\O CP h 3.45The reaction of p-benzquinone with esters of amino-acids, result-ing in the formation of highly coloured compounds, is less simple,hydrogen being eliminated from the amino-group, so that some\-/quinol is formed.The product from glycine has the formula:000, Et * CH, * N H j ' j 46 11 IINH*CH,*CO,Et \(041 J.Schmidlin and R. VOII Escher, Ber., 1910, 43, 1153; A . , i, 369; H.42 J. Schmidt and H. Wagner, ibid., 1796 ; A., i, 550.43 K. H. Meyer, ibid., 157 ; A . , i, 179.45 J. Schmidlin, J. Wohl, and H. Thommen, ibid., 1298 ; A . , i, 377.46 E. Fischer and H. Schrader, ibid. , 525 ; A , , i, 270.Finkelstein, ibid., 1533 ; A., i, 469.44 A. Knorr, ibid., 798 ; A., i, 32ORGANIC CHEMISTRY. 75The great additive power of polynitro-compounds, such as tetra-nitromethane, was remarked last year, and has received furtherattention. s-Trinitrobenzene forms coloured additive compoundswith arylamines, phenols, and phenol ethers, but not with amino-phenols. Almost complete dissociation takes place in benzene solu-tion, as is shown by determinations of the molecular weight.47s-Trinitrobenzene also forms coloured compounds with hydrazine,phenylhydrazine, and azobenzene. The colour thus produced ismuch deeper than when salts are formed, a in the hydrazine saltsof nitrophenols.Trinitrotoluene only yields a very unstable redcompound, and trinitroxylene and trinitromesitylene do not formcoloured additive products.48The relation between colour and constitution has been studiedin a series of unsaturated ketones and salts' derived from them.49The starting point of the research was the two compounds, distyrylketone (I) and dibenzylidenecy clopentanone (11) :(I.) C,X,--CH=CH--C-CH=CH-C,H,. .. 00The chromophoric groups in (I) are further reinforced by theformation of bhe ring, so that derivatives of (11) have a deepercolour than those of (I).By replacing the hydrogen of the phenylresidues by alkyl or alkyloxy-groups, the basicity of the ketonecould be varied, and the colour of the solutions obtained on dis-solving the substituted ketones in various acids compared. Themore basic the ketone employed and the stronger the acid used Msolvent, that is, the more complete the salt-formation, the deeper isthe colour of the solutim. By cooling to a low temperature incontact with hydrogen chloride, several molecules of the latter maybe taken up, with corresponding intensification of the colour.The quantitative effect of closing the ring on the colour of thederivatives examined and of their salts is always the same.If thechain of conjugated double linkings is increased by changing frombenzylidene to cinnamylidene compounds, the colour is still furtherdeepened, that is, the absorption is moved further towards the red.Fury1 has a greater effect on the colour than phenyl. Preciselysimilar observations have been made with derivatives of fluorenone,and of chrysene and indene.47 J. J. Sudborough and S. H. Beard, Trans., 1910, 97, 773.43 K. A. Hofmnnn and H. Kirmreuther, Ber., 1910, 43, 1764 ; A., i, 548,4Q €3. Stobbe, Annalen, 1999, 370, 93 ; A , , 1910, i, 4376 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Another interesting study relates to the aminocoumarins, whichare coloured, and the colour is not destroyed when the aminegroupis fully methylated, or when the two hydrogen atoms of thecoumarin are replaced by methyl.Acylation, or the formationof a quaternary salt, destroys the colour. The hypot,hesis of anoscillation of linkings is proposed in explanation, on lines similarto those already suggested by other workers.50Triketohydrindene hydrate is colourless, and must have the con-stitution C,H4<gg>C( OH),. Similar colourless additive com-pounds are obtained in which the water is replaced by guanidineor benzamidine.Potassium hydroxide produces a solution which is first yellow,then blue, and then colourless, a series of changes which may beexplained by the opening and closing of the ring in the followingmanner 51 :CH(0H) *CO,H//,,CO*CHO /\/c(oH)<co //\/ I JI -+I I ’ -+ I II\/\CO,H \ / \ ~ ( O ~ ) / O N/\CO,HPhenylglyoxal- o-Qaiaonoid o-Carboxy-o-carboxylic acid.blue salt. mandclic acid.Incidentally, many other discussions of the relation betweencolour and constitution are found in communications dealingprimarily with questions of structure alone.Coloured Salts.-Reference has been made on several previousoccasions 52 to the investigations of Hantzsch and others, dealingwith compounds which form two or more series of differently colouredsalts. Such cases of “pantochromism” are frequently puzzling, owingt o the difficulty of distinguishing between true chemical isomeridesand merely polymorphic modifications. It seems probable, in fact,that many instances of this kind lie just on the border-line, wherea satisfactory formulation is at present beyond our powers, and thesuggested explanations, sometimes stereochemical and sometimesresting on the principle of subsidiary valency, can only be regardedas extremely hypothetical, fulfilling the temporary purpose ofclassifying the phenomena.One of the most familiar instances of pantochromism is that ofvioluric acid and its salts.The following are the principal conclusionsarrived at. from a study of these and other oximinoketonederivatives.53 The colour of solutions of the violurates deepens fromyellow and orange through red and violet to blue with increasing50 A. Clayton, Trans., 1910, 97, 1350.51 S. Ruhemann, i b d . , 2025.53 A. Hantzsch, Ber., 1910, 43, 82; A., i, 200.s2 Ann.Heport, 1909, 67ORGANIC CHEMISTRY. 77positivity of the metal and increasing residual affinity of thesolvent. All the solutions contain unimolecular salts. Spectroscopicexamination shows that the pale yellow solutions of the ketonescontain true oximino-compounds, whilst the blue solutions resemblenitrosccompounds. These differences may therefore be attributedto chemical isomerism :YelIow. Blue.The intermediate colours are due to mixture of these two forms,and may be imitated by mixing the pure modifications. Such factsas these do not, however, account satisfactorily for the simultaneousseparation of both red and yellow crystals of the same salt froma single solution, or for the formation of a red and a yellow lithiumsalt, but of a blue and a flesh-coloured czsium salt.The oximino-oxazolones form unimolecular salts, those with weakbases being generally yellow, whilst those with strong bases aremore or less blue, so that there is little difficulty in attributing thedifference in colour to the predominance of the oximino-ketone formin the first, and of the nitroso-enol form in the second case.54Similar relations are observed among the dimethyl- and diphenyl-violurates.55 These salts, however, undoubtedly form colouredadditive compounds with certain solvents, such as pyridine andphenol, and such results point to the necessity of making fullanalyses before considering salts of this class as exhibiting trueisomerism.In the case of the hydroxyazccompounds, however,although the yellow series of salts generally separates with solventof crystallisation, this does not appear to be the cause of the colour,but only to increase the stability of the yellow modification in thesolid state, its each form yields solutions of its own colour.56The formulz proposed are:Yellow. Red.which do not differ in any clear manner from those of a hydroxyazo-compound and a quinonehydrazone respectively.A further complication is introduced by the existence of differentmodifications having the same colour, and yielding optically identicalsolutions.To such a condition, which includes such familiarinstances as the syn- and anti-oximes and other stereoisomerides,b4 A. Hantzsch and J. Heilbron, Ber., 1910, 43, 68 ; A . , i, 198.m A.Hantzsch and R. Robison, ibid., 45, 92 ; A., i, 196, 200.E6 A. Hantzsch and P. W. Rotiertson, ibid., 106 ; A., i, 203'78 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the name of (( homochromoisomerism " is given. Both chromeisomerism and homochromoisomerism are observed in the nitro-anilines, a good example being given by 2 : 4-dinitrophenyltolyl-amine,NO, MeCHC13aridpetroleum.the relations between the isomerides being shown in the followingscheme 67 :Cold dil. alcoholic solution.Yellow 3 Orange(stable)Hot conc. alcoholic solution.water.Acetonitrile.Orange r__ ____ + Yellow(labile) f (lab i 1 e)Most solvents.Acetone.The two kinds of yellow solutions, although optically identical,deposit different yellow salts on crystallisation. The whole of thesalts are unimolecular in solution.Azophenol is known to exist in two modifications, one of which,a-azophenol, obtained from p-nitrophenol, being green, and the&modification, obtained from quinoneazine, being dark red.Thecolours become more nearly alike in their hydrates. It is nowfound 58 that, distinct a- and P-salts exist, regenerating their parentsubstances. These salts are pantochromic, crystallising in yellow,red, and green modifications, so that a maximum number of sixsalts may be obtained from each metal. The u- and &compoundsare regarded as stereoisomerides :OH. C,H, M OH* C,H4 =W0 H*C,H,*N N-C,H~.OH'and in accordance with this assumption both modifications yieldA. Hantzsch, Ber., 1910, 43, 1651, 1662; A , , i, 474, 475.68 A.Haatzsch, ibid., 2512 ; A,, i, 790ORGANIC CHEMISTRY. 79optically identical solutions, whilst the respective salts also haveidentical absorption spectra. The difference in' colour of the solidazophenols and their salts is attributed to valency-isomerism, thelabile form passing into the more stable on dissolution. Formulzefor these isomerides are proposed, namely :.................... ...................... iu MO*C,H,.N: N-c,H,* 6 o*c,H,*N: N . C , H , ~I M i ...................... I 1 M ...................... I..................... i Mo~c,H,~~N~c,H,~o ,1. M I....................andbut, as in most similar instances, it is difficult to form a clearphysical image of the conditions intended to be represented by sucharrangements of subsidiary valencies.It is known that the coloured salts of the colourless s-trinitro-benzene are not simple salts, but alcoholates, such as (I).The saltsH OMe Ph-NH OEtof picrylaniline are found59 to have a similar composition, thepotassium salt in alcoholic solution, for example, having theformula (11). Some compounds of this class are capable of com-bining with two or three molecules of alkoxide, and as the resultingcompound approaches more nearly to the saturated condition, thetrialcoholate being a derivative of cy clohexane, the colour becomescorrespondingly lighter. Dinitro-compounds can form mono- anddi-alcoholates.A bsorption Spectroscopy.-Attention has been once more directedto the spectroscopic method of investigating equilibria in substancesexhibiting keto-enolic tautomerism.A very thorough study of ethylacetoacetate and its derivatives and salts in a number of differentsolvents 60 leads to the conclusion that the selective absorptionobserved in solutions of the salts is not due to the enolic modificationor to an oscillation bet.ween the ketonic and enolic conditions, butto an isomeric aci-form. Enolisation of the parent substance takesplace to a varying extent in different solvents, in such a way thatthe proportion of ketone increases with the dielectric constant of the5y RI. Busch and W. Kogel, Ber., 1910, 43, 1549 ; A . , i, 472.6o A. Hantzsch, ibid., 3049; A . , i, 81180 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.solvent, but the absorption thereby produced is never selective.On the other hand, the solutions containing alkali always absorbselectively.The aczrrnodification must be derived from the enol,and the great difference in absorptive power excludes mere stereo-chemical cis-trans-isomerism. It thus becomes necessary to invokethe aid of the subsidiary valencies, and the following formulationis proposed:CH,*yO -+ CH,*E*OH -+ CH,*E-OHCO,Et*CH, t- CO,Et*CH t- H-C. CO-OE~Keto. End. Aci.the suggestion being made that the enol is only stable in the trans-configuration, whilst the &configuration a t once passes into themi-form. This stereochemical hypothesis is, of course, not anessential part of the explanation. The fact that the addition ofsuccessive quantities of alkali increases the absorption until amaximum is reached is explained as being due to the hydrolysis ofthe salts, which are only stable in the presence of a large excessof alkali, so that solutions which do not contain such an excess arecomposed to a large extent of the enol, which does not give riseto selective absorption.The conclukions derived from the spectroscopic evidence as to theequilibrium between the ketonic and enolic modifications in differentsolvents are in general confirmed by determinations of the refrac-tivity, and are also in accordance with the observed time-effects inthe ferric chloride reaction, although the latter is not suitable forthe quantitative study of the equilibrium.Another long series of spectroscopic observations of compounds,many of which exhibit keto-enolic tautomerism, relates t o camphorand its derivatives.61 It is found that the simple ketones, suchas camphor and its a-derivatives, absorb selectively to an extentwhich varies with the solvent and with the concentration.Theform and position of the absorption band is quite independent ofthe tendency t o undergo isomeric change, as shown by the mutiGrotation, and depends rather, as in other cases, on a particulardistribution of residual affinity throughout the molecule. Theapplication of considerations similar to those employed byFliirscheim 62 in the discussion of reactivity accounts satisfactorilyfor the position of the bands in many of the derivatives of camphor,the absorbing group being :::*O=C-C=C-()<:.The case ofnitrocamphor and its derivatives stands somewhat apart, and fallsinto relation with that of the aliphatic nitro-compounds, the great61 T. M. Lowry and C. H. Desch, Trans., 1909, 95, 807, 1340 ; T. M. LOWTY,C. H. Desch, and H. W. Southgate, ibid., 1910, 97, 899 ; T. M. Lowry and H. W.Southgate, ibid., 905.I l l6'2 Ann. lipport, 1909, 60ORGANIC CHEMISTRY. 81selective absorption observed in alkaline solutions being directlyconnected with the formation of a distinct mi-modification. Anextensive series of aromatic nitro-compounds has also been examinedspectroscopically,63 with rather different results, the absorption beingattributed to the influence of the unsaturated nitro-group on thepulsations of the ring, as modified by other substituents, and thequinonoid structure being rejected for the salts and aci-modifications.The principal argument in favour of this view is the appearanceof the characteristic band at about the same concentration through-out a long series of compounds, some of which are incapable ofreceiving a quinonoid formulation, such as the dialkylated mono-amines.The groups *'ONa, *NH,, and ONMe,, when associated withone or more nitro-groups in an aromatic compound, produce prac-tically identical effects on the absorption, and as dinitrodimethyl-aniline, for example, cannot possibly be quinonoid, it is consideredunnecessary t o assume such a structure for the nitroanilines or thenitrophenoxides. As in several other researches referred to above,the influence of the residual affinity of the solvent employed on theposition of the absorption band is very conspicuous in the publishedcurves.An extension of this work to nitrated azo-compounds leads to theresult that the nitrobenzeneazophenols and their salts have entirelysimilar spectra, the absorption of the latter being shifted towardsthe red.m- and p-Nitrobenzeneazodimethylaniline resemble thealkali salts, this being a further argument against a quinonoidstructure for the salts of the nitro-compounds.64Two series of phydroxyazo-derivatives of quinoline (I and 11)give spectra indicating that they have the azo-constitution, and arenot quinonoid :/-\N:N/-\()H ()H/-\N: N/-\/-& /-&\-/ \ / \-/ \ /(1.) (11.)The dihydrochlorides of (I) are very unstable in comparison withthose of (11), which is taken to indicate that the second moleculeof hydrogen chloride is attached to oxygen rather than to carb0n.~5Only the merest reference can be made to other spectroscopicinvestigations. A number of bases have been examined, theabsorption spectra of the pure liquid in thin films, of the vapour,and of solutions in various solvents being observed, but it willevidently be necessary to accumulate it large quantity of data before63 E.C. C. Baly, W. B. Tuck, and Miss E. G. Marsden, Trans., 1910, 97, 571.\-/ \-/E. C. C. Baly, W. B. Tuck, and Miss E. G. Marsden, ibid., 1494.65 J. J. Fox, ibid., 1337.REP.-VOL. VII. 82 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRP.any general conclusion can be drawn, owing to the great differencesexhibited by these spectra.The absorption spectrum of the vapouris often remarkably complex.66 Other investigations relate to iododerivatives, and to a comparison of the groups *N:N* andCH : CH .67Stereochemistry .Recent work in stereochemistry has been confined, for the mostpart, t80 matters of detail, and no great advance in principle has tobe recorded. Attempts to find a quantitative relationship betweenthe degree of asymmetry of a molecule and its optical activity havemet with littile success, and the problem of t’he asymmetryproduct ” therefore receives less attention now than was the casea few years ago. A branch of study which properly falls underthe head of stereochemistry, although unconnected with opticalactivity, is the establishment of relations between constitution andcrystalline form, especially by means of Pope and Barlow’s con-ception of valency volumes.The most important application ofthis doctrine to organic chemistry during the past year has beenthe examination of the sulphonyl chlorides and bromides of ths1 : 4-dihalogen derivatives of benzene,6* an extensive series ofmeasurements leading to results according very satisfactorily withthe requirements of the hypothesis, but the details fall outside thescope of this report.A great number of practical points in the study of optical activityhave received attention. The observation that the activity ofcertain alkaloids does not correspond with that of their saltsG9indicates a possible source of error in working with optically activetertiary bases, against which it is necessary t o take precautions.Resolution.-It is well known that the process of resolution ofexternally incompensated acids or bases by crystallisation of theirsalts with an optically active base (or acid) is often, if not usually,complicated by t>he tendency of the salts d-acid + d-base and d-acid +Z-base, to form crystals containing both individuals.Such mixturesmay behave in one or more of three well-defined ways:(1) Each crystal which separates may contain only one salt, inwhich case an easy separation may be effected by the method ofPope and Peachey. (2) The crystals may consist of a partly racemic66 J.E. Purvis, Trans., 1910, 97, 692, 1035, 1546, 1648; Miss A. Homer andJ. E. Purvis, ibid., 280 ; K. Schaefer, Zeitsch. wiss. Photochcm. , 1910, 8, 212, 257 ;A., ii, 562.67 C. R. Crymble, A. W. Stewart, and R. Wright, Ber., 1910, 43, 1183, 1188,1191 ; A , , ii, 470.88 H. E. Armstrong, Trans., 1910, 97, 1578 ; R. T. Colgate and E. H. Rodd,ibid., 1585.69 F. H. Carr and W. C. Reynolds, ihid., 1328ORGANIC CHEMISTRY. 83compound^' of the two salts, and here no resolution by theforegoing method can be effected. (3) Each crystal may containboth salts, but in varying proportions; in other words, the saltsform solid solutions in one another, and in this instance resolutionis very slow and incomplete.The resolution of externally compensated camphor-?r-sulphonicacid with one-half an equivalent of strychnine forms an excellentexample of the first type.An instance of type 3 has been observed,namely, that of the resolution of l-methylcylcZohexylidene-4-aceticacid by brucine ; the separation of d-bornylamine from d-meobornyl-amine by means of d-a-bromocamphor-r-sulphonic acid, and also ofthat of d-menthylamine from d-isomenthyla'mine by crystallisationof their mixed hydrochlorides are also complicated by the formationof solid solutions of the two component salts.70Racemic Compounds.-An observation of recent date appears tooffer unequivocal evidence in favour of the view that racemiccompounds may exist in tEe liquid state or in solution, the rateof decomposition of camphorcarboxylic acid in acetophenone solutionbeing 3 per cent.less when a mixture of the d- and Z-acids is usedthan when either is present alone.71The appearance of a maximum on the freezing-point concentrationcurve of mixtures of two optical isomerides is evidence of theformation of a stable racemic compound on solidification, and hasbeen considered t o afford a presumption that such a compoundexists in the liquid mixtures. Such a maximum is stronglymarked in the curve of mixtures of d-, I-, andinactive a-pipecoline.72 The solubility of dipentene is unaffected bythe addition of one of its active components, and the same is trueof dZ-2-ethylpiperidine, from which the authors concIude that aracemic compound is not formed in these cases.A sgmmetry.-The case of methylcyclohexylideneacetic acid,synthesised and resolved into its enantiomorphous constituents,remains the only known case of a substance which owes its opticalactivity t o molecular asymmetry and not to the presence of asym-metric atoms in the sense commonly understood.A substancewhich appears t o be diphenylnaphthylallenecarboxylic acid,freezing-pointhas recently been synthesised 73; this structure represents one of thesimplest types of asymmetric molecules, but attempts to resolve thecompound into its active constituents have not been successful.To W. J. Pope and J. Read, Trans., 1910, 97, 987.71 K. Fajans, Zeitsch. physikal. Chem., 1910, 73, 25 ; A., ii, 599.72 A. Ladenburg and Sobecki, Ber., 1910,43, 2374 ; A., i, 769.73 A.Lapworth and E. Wechsler, Trans., 1910, 97, 38.G 84 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.A novel method of obtaining a substance having a molecule withan enantiomorphous constitution in virtue of the arrangement ofgroups attached to a silicon acom has proved successful. Thestarting point was dibenzylet hylpropylsilicane, SiEtPr(CH2Ph), ;on sulphonation this yielded a mono- and a di-sulphonic acid, theformer of which contained an asymmetrical silicon atom, and wasfinally resolved into its enantiomorphous components by means ofbrucine; the rotatory powers of the active forms were small, [aIDbeing about lo, but satisfactory evidence was adduced that it realresolution had been effected. Although but few cases of opticallyactive silicon compounds have been obtained, ii; is certainly remark-able that all of them exhibit the true physical characteristics ofenantiomorphous substances, bub display only very feeble opticalact ivit y.74Ap$ications of St ereochemkal Properties.-The synthesis ofamidines, containing two different basic radicles, may result in theformation of one or other of the two possible isodynamic forms,NR1:CR*NHR2 and NR*CR:NR2, or a mixture of both may beobtained.The former appears to be the case when the radiclesR1 and R2 are dissimilar in character, and the latter when theseradicles are closely related. This subject has recently been studiedwith the aid of optically active radicles, and it is found that thefollowing formulz represent stable compounds, C,,H,, being themen thy1 radicle :C,H,*NH*CPh:N*C,,H,, and C2H,*NH*CPh:N*C,,HlS.When the radicle R and R, are identical in chemical character, itwas to be expected that the two isomerides would be equally stable,and that each would constitute one-half of the product. This wasconfirmed by preparing an amidine, in which R and R, were d-bornyland Z-bornyl respectively when the product was found to beoptically inactive, and therefore consisted of equal quantities of thetwo isomerides :( I ) C,,,H,,*NH*CP h: N*C,,H,, (d) and(I) C,,,Hl7*N: CP h*NH C,,H,,(d) .75The ethylated compound was also inactive, and could not beresolved by crystallisation of its d-camphorsulphonate.A further instance of the use of optically active compounds inthe study of isodynamic isomerism is of interest, as bearing on theold controversy as to the constitution of the dichlorides of thosedicarboxylic acids which readily yield internal anhydrides, suchas those of the succinic and phthalic acid series.It was foundthat l-methoxysuccinyl dichloride, even when crystalline and74 F. Challenger and F. S. Kipping, Trans., 1910, 97, 149 755.75 J. B. Cohen and J. Marshall, ibid. 32ORGANIC CHEMISTRY. 85freshly prepareci, did not exhibit mutarotation, even in presence ofsuch a powerful agent as aluminium chloride or in closed tubes atlooo; it is therefore highly improbable that the compound exists intwo isodynamic forms.76The Waldem Znuersion.-The report on Stereochemistry for lastyear indicated in a concise manner the stage then reached byinvestigation in this subject.Comparatively few additional com-munications have appeared during 1910, but some of these representmost important advances.It has previously been held that phosphorus pentachloride reactsnormally with a-hydroxy-acids, or, in other words, causes noinversion of the special distribution of the groups around thea-carbon atom; the first exception to this rule has been observedin the case of a-hydroxy-P-phenylpropionic acid,C H,P h- CH (OH) C0,H.The d-acid is converted into a chloro-acid chloride, from which, bythe action of moist calcium carbonate, impure Ehydroxyphenyl-propionic acid is obtained. This appears to be the first instance inwhich phosphorus pentachloride behaves in an abnormal manner.77Thionyl chloride, on the other hand, behaves normally, and theZ-hydroxy-acid is converted by this agent into the corresponding2-chloro-a~id.7~The majority of acids which have been closely investigated inconnexion with the Walden inversion hav.e contained amidogen,hydroxyl, or halogen attached to an asymmetric carbon atomsimultaneously with a hydrogen atom and a, carbonyl group, thus:C-C0,H./OH\HFischer and Scheibler, who studied the reactions of Z-P-hydroxy-butyric acid, CH,-CH(OH)*CH,*CO,H, found no evidence of theoccurrence of any inversion in this case. More recently, activeP-hydroxy-P-phenylpropionic acid, OH*CHPh*CH,*CO,H, has beeninvestigated with similar results, although slight racemisation wasdetected.79 Acids with this type of grouping do not thereforeappear to undergo inversion.The corresponding P-amino-B-phenylpropionic acid and its esters,when treated with nitrous acid, are converted into the hydroxg-acidswith some racemisation, but in this case, too, no Walden changeoccurs.80 On the other hand, the derivatives of active a-hydroxy-76 T.Purdie and C. R. Young, Trans., 1910, 97, 1524.77 A. McKenzie and H. Wren, ibid., 1355.78 A. McKenzie and G . W. Clough, ibid., 2564.79 A. McKenzie and H. B. Humphries, ibid., 121.80 E. Fischer, H. Scheibler, and R. Groh, Ber., 1910, 43, 2020 ; A,, i, 62286 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.a-phenylpropionic acid gave positive results, and the most significantobservations may be gathered from the following scheme 81 :( p > C < & (by so2cw + (1)g>c<&(d)Me>C<CO,H Ph c1 - (by SO2C12) ( d ) ~ > C < ~ ~ 2 ~(bYAL720 IJ.and water)(bv A@ I f I and watsr)Partial racemisation occurred during the hydrolysis of the chloro-acids by moist silver oxide, but this is probably to be ascribed toit secondary action due to the water, which brings about thecomplete racemisation of the active acids at the ordinary tem-perature. The inquiry establishes conclusively that the presenceof a hydrogen atom in attachment to the asymmetric carbon isnot a necessary condition for the occurrence of the Walden inversion,and thus appears to represent one of the most important con-tributions to this subject.It has been shown that when Z-brommuccinic acid is treated withdibenzylamine, a malamic acid is formed by a normal process,whilst at the same time an aspartic acid is formed by a processinvolving optical inversion.A similar phenomenon is noticed whenmethylamine is used, the products being d-#I-methylmalamic acidand an Z-methylaspartic acid; the configuration of the lattercompound, however, has not yet been conclusively established.82Constitution and Optical A ctivity.-Recent work on the relationbetween the chemical constitution and rotatory power of opticallyactive substances has dealt chiefly with the effect of unsaturation.The influence of the position of the double linking in benzoic,a- and B-naphthoic, terephthalic, and muconic acids, and theiyhydrogenated derivatives, examined in the form of their menthylesters, shows83 that when the double linking is in the By-positionthe rotatory power is nearly the same as when the acid is com-pletely saturated, whilst acids having a double linking in theaB-position are usually more active, but are less so in the cases ofthe tetrahydroterephthalic and dihydro-B-naphthoic acids.Thereduced Eenzenoid esters are usually less active than the correspond-ing benzenoid compounds, and this also applies to the muconicseries, but menthyl Al:4-dihydroterephthalate is slightly more activethan menthyl terephthalate.An attempt has been made 84 to apply the known effect of con-jugated double linkings on rotatory power to the determination of81 A.McKenzie and G. W. Clough, Trans., 1910, 97, 1016.82 0. Lutz, Zeitsch. phgsikal. Chem., 1910, 70, 256 ; A., i, 230.83 H. Rupe, Annalen, 1910, 373, 121 ; A., i, 398.84 T. P. Hilditch, Trans., 1910, 97, 1091ORGANIC CHEMISTRY. 87constitution in a doubtful case, that of the a-disulphoxides, to whichthe alternative formulas :R-S=S*R and R*S*S*R(1.) (11.)have been assigned. The formation of these compounds fromsodium alkylthiosulphonates and alkyl iodides favours (11), whilst(I) is more consistent with the ready reduction to a disulphide.As (I) is a symmetrical structure, containing conjugated doublelinkings, whilst (11) is unsymmetrical, the optical method isapplicable. Dicamphoryl j3-a-disulphoxide, examined in this manner,behaves as a conjugated compound, and must have the symmetricalstructure, but when the two radicles are very unlike, as in camphorylmethyl disulphoxide, the rotatory power approaches that of theunsymmetrical compound, sodium camp horyl-j3-thiosulp honate.Thecamphoryl It-butyl compound gives values lying between the two,which is taken to indicate the presence of t'wo isomerides, althoughattempts to isolate isomeric modifications in this series have provedunsuccessful. The results of the investigation are therefore some-what ambiguous.The aldose sugars and their glucosidic and lactonic derivativeshave a much greater rotatory power than the corresponding alcoholsand acids, and a considerable optical effect is therefore attributableto the lact,one ring.As there are two possible stereochemicalpositions for the ring, determined by the position of the hydroxylgroup attached to the y-carbon atom before the ring was produced,it is suggested 85 that dextrorotatory lactones have the ring onone side, and lzvorotatory lactones on the other side, of the structure.Tables are given confirming this conclusion by a comparison of therotatory power of the lactones with the configuration of the parentsubstances.I n continuation of previous work on the influence of po;sitionisomerism on optical activity,86 the menthyl esters of the isomericalkyloxy- and alkylamino-benzoic acids have been examined.87Incidentally, the importance of the effect of temperature is clearlybrought out, it being found that isomerides which fall into anapparently abnormal order if examined at the ordinary tem-perature, reproduce the more usual order at higher temperatures.A t a temperature of looo the results are more regular, and a generalrule, applicable to substituted rnenthyl benzoate8 containing eitherpositive or negative substituents, emerges, namely, that the ortho-85 C.S. Hudson, J. Amer. Chern. Soc., 1910, 32, 338; A., i, 220.85 Ann. Rtport, 1906, 191. *' J. B. Cohen and €3. W, Dudley, Trans., 1910, 97, 1732.46 $88 ANNUAL REPORTS ON THE PROGHESS OF CHEMISTRY.substituent has the greatest influence, and the meta- and para-substituents a much less effect.Solvent 2nfluence.-Further work has appeared on the influenceof solvents on the rotation of a dissolved substance.I n a series ofexperiments, in which ethyl tartrate was used as the active sub-stance,sB phenol and p-nitrophenol are shown to exert a great solventinfluence, which largely disappears in the corresponding ethers.On the other hand, o-nitrophenol has a small influence, which isincreased when the phenolic group is alkylated. Two hydroxylgroups also have the greatest effect when in the p-position, andleast in the o-position. p-Benzoquinone has less effect than aphenol, so that the evidence, so far as it goes, points to a quinonoidstructure for o-nitrophenol in mixtures with ethyl tartrate.An application of the fact of solvent influence to the analysisof mixtures has been made, and presents distinct advantages incertain cases in which chemical analysis is difficult to perform.Thusthe quantitative estimation of beniene in cyclohexane is difficultand troublesome, but by taking advantage of the fact that benzeneis almost without influence on the rotation of ethyl tartrate, whilstcyclohexane exerts a considerable depressing influence, the pro-portions of the two substances present in a mixture may beestimated within about 3 per cent. by the simple determination ofthe rotatory power of a mixture with a fixed proportion of theester.89In previous papers by Patterson and others, the possibility thatsolvent influence in certain cases is due to combination of thesolvent with the solute has frequently been discussed, but directevidence of the existence of such compounds in solution is, fromthe nature of the case, very difficult to obtain.By using diethyldiacetyltartrate as the active substance, it has been found possibleto determine the freezing-point curves of a number of binarysystems, the second component of which is inactive. All thesesystems are proved to form simple eutectiferous series, whilst withmixtures of Z-menthol with nitrobenzene, naphthalene, and anethole,indications are obtained of the pmsible existence of highly dis-sociated compounds. The absence of a maximum or of a distinctbreak in the freezing-point curve is, of course, not conclusive againstthe existence of compounds in the liquid at higher temperatures,but it affords a certain amount of evidence against their existence.Measurements of the viscosity and dilatation fail to give anyevidence of combination, and it is evident that the materials for88 T.S . Patterson and Miss E. F. Stevenson, Trans., 1910, 97, 2110.89 T. S. Patterson and A. Fleck, ibid., 1772.90 0. Scheuer, Zeitsch. physikal. Chem., 1910, 72, 513 ; A., ii, 470ORGANIC CHEMISTRY. 89a satisfactory theoretical discussion of the conditions in suchsolutions do not yet exist.The measurement of the rotatory dispersion does not, as a rule,afford much information beyond that givcn by the simple rotation.Determinations of the dispersion of ethyl tartrate and of ethylmalate in a large number of solvents91 show that, if the specificrotation in red light is higher than that of the pure ester, therotation rises from red to blue, whilst it falls if the rotation wasoriginally lower than that of the ester.Some of the solvents usedwere such as would react chemically with the esters used, and theresults in such cases are obviously not comparable with the others.Stereoisomeric Substituted Glutaconic Acids.-Glutaconic acidand many of its'alkyl derivatives have been obtained in one formonly, and this circumstance was adduced in favour of a dynamicformula for these substances, in which one of the a-hydrogen atoms,in the a-position, is ima.gined to be held in a state of suspense o rvibratile motion between the two a-carbon atoms.g2 The existenceof stereoisomerism among some of these compounds wa8 afterwardsdemonstrated for the P-methyl derivative,93 and more recently for avariety of other substituted glutaconic acids.94The previously known forms are readily converted into anhydrides,which, on hydrolysis by the usual processes, at once give rise to theoriginal acids; for this reason they have hitherto been mistaken forthe cis-representatives.I n reality the true cis-forms, correspondingwith the anhydrides, are unstable towards the agents generally usedfor hydrolysis, and as soon as produced undergo a transformationinto the original trans-acids, from which the anhydrides are pre-pared. The stability of the different forms of these acids is,however, great'ly affected by the number and positions of the sub-stituent groups in the molecule.The isolation of the cis-forms can only be accomplished bycarrying out the hydrolysis extremely carefully in presence ofcolloids (preferably casein), which appear to retard the stereo-isomeric change.Thus the two isomeric a-methylglutaconic acids are preparedfrom ethyl dicarboxymethylglutaconate by the action of aqueousalkali. The cis-form may also be obtained from the well-knowntrans-acid by converting the latter into its anhydride, and allowingit to absorb moisture from the air or by hydrolysing it with acids91 H.Grossmann, Zeitsch. physikal. Chem., 1910, 73, 148 ; H. Grossmann andB. Landau, ibid., 75, 129 ; A., ii, 563, 1017.g2 J. F. Thorpe, Tram., 1905, 87, 1669.93 F. Feist, Annalen, 1906, 345. 60 ; A . , 1906, i, 334.gd F. Feist, ibid., 1909, 370, 41 ; F. Feist and G. Pomme, ibid., 61, 72 ;F.Feist and R. Reuter, ibid., 82 ; A., i, 7, 9, 3990 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,or alkalis in presence of casein; it retains its configuration whenfused, but it inverted by aqueous sodium hydroxide or hydrochloricacid.Glutaconic acid itself has been obtained in only one form, anduntil its cis- and trans-forms have been isolated, the dynamicexplanation of the behaviour of this and similar compounds is notlikely to be discarded by those chemists to whom it appears to offerany theoretical advantages.95The Cinnamic A cids.-The supposed existence of a number ofisomeric cinnamic acids 96 is now only maintained by Erlenmeyer,and a quantity of evidence is being accumulated in support of theview that the allo- and iso-acids are dimorphic modifications.Itis found 97 that most elaborate precautions are necessary to preventaccidental inoculation with crystals of one or other of the labilemodifications during recrystallisation experiments, and that whensuch inoculation is most completely excluded, the product is almostalways the stable iso-acid, melting at 4 2 O . Solutions of these threeacids are completely identical in electrical conductivity 98 and intheir absorption spe~tra,~g whether water or alcohol is used as thesolvent, whilst a solution of the ordinary acid shows a small butdistinct difference in the form of the absorption band.The statement that ordinary synthetic cinnamic acid containstwo isornerides, a- and 6-heterocinnamic acid, which are not presentin the acid from storax, has not been allowed to pass unchallenged,and a careful crystallographic study shows1 that the markeddifferences of crystalline habit between the natural and the syntheticacids may be produced by the presence of a small quantity of theo-chloro-acid in the latter. Other impurities, such as o-nitro-cinnamic acid, have a precisely similar effect.The a- and P-hetero-cinnamic acids are thus probably fractions in which the impurityhas been concentrated. This explanation accords with the fact thatthe two supposed new acids melt at 1 2 8 O , a few degrees lower thanthe pure acid, and although experiments are described2 to provethat the differences persist in the absence of all such impurities,they are hardly conclusive, and it appears almost certain that thenumber of stereoisomeric cinnamic acids does not exceed the tworequired by theory.95 Compare A.F. Campbell and J. F. Thorpe; Tram., 1910, 97, 1299.96 Ann.. Report, 1909, 133.97 C. Liebermann and H. Trucksbs, Ber., 1909, 42, 4659 ; 1910, 43, 411 ; A.98 E. Biilmann and N. Bjerrum, ibid., 1910, 43, 568 ; A., i, 346.99 H. Stobbe, ibid., 604; A., ii, 247.i, 36, 175.1 C. N. Riiber and V. M. Goldschmidt, ibid., 453 ; A., i. 174.2 E. Erlenmeyer and G. Hilgendorff, ibid., 955, 1076 ; A , , i, 320, 383ORGANIC CHEMISTRY. 91In order to confirm the generally accepted configurations of theordinary and allo-acids by an entirely independent method, areaction has been employed which is generally applicable to olefineacids.3 Mercuric acetate yields complex mercury salts with themalenoid forms of such acids, and in the case of allocinnamic acidforms an inner salt of a-mercuri-8-hydroxy-8-phenylpropionic acid,This acid is therefore regarded as having the cis-configuration,leaving the trans-configuration for the ordinary acid, which doesnot react under similar conditions.The Stereochemistry of Nitrogen.Although it is generally considered that the existence of isomericcompounds of the formula Nabc has been disproved, the questionof the configuration of molecules containing tervalent nitrogenpossesses sufficient interest to serve as the motive of further investi-gations from time to time.Thus two isomeric compounds weredescribed in 18964 as being obtained by the interaction ofm-4-xylidine and acetaldehyde in dilute hydrochloric acid, and thesimilarity of the chemical properties was such that the isomerismwas then attributed to the arrangement of the three groups aboutthe central nitrogen atom:C,H3Me2-$;-CAMe*C€T2*CH0.HA re-investigation of these compounds 6 proves that theirdifferences are really due to structural isomerism, and their chemicalbehaviour is best explained by assigning to the a-isomeride theformula given above, and to the less fusible and soluble P-form aclosed-ring formula :Neither compound is converted into the other by the action ofsolvents or of heat, but an equilibrium mixture is produced by theaction of acids.Certain differences in the behaviour of the twoisomerides towards nitrous acid remain unexplained, and theabsorption spectra are inconclusive.Like the above, most compounds of the formula Nabc are basicin character. A compound having acid properties has also beenexamined, the attempt being made to bring about a, separation ofE.Biilmann, Ber., 1910, 43, 568 ; A, i, 346.W. v. Miller and J. Pliichl, ibid., 1896, 29, 1462; A . , 1896, i, 534.H. 0. Jones, Trans., 1910, 97, 632; J. E. Purvis, ibid., 64492 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.isomerides, if present, by the crystallisation of salts with activealkaloids.6 This compound is 2 : 3 : 5-trinitro-4-acetylaminophenol,CH,*CO-r-~,H(NO,),*O€~,which forms a stable salt with brucine, but the acid compoundliberated by acids from the brucine salt is found to be devoid ofoptical activity.Amongst compounds containing quinquevalent nitrogen, those inwhich the nitrogen occurs in a piperidine ring have proved interest-ing, from the considerable influence of the size of the groups attachedto atoms directly linked to the nitrogen atom on the asymmetryof the molecule.7 Thus dZ-6-phenyl-2-methyl-l-ethylpiperidine com-bines with ally1 iodide, yielding two stereoisomeric quaternaryammonium salts.* I n the course of the same investigation, anexample of stereoisomerism in compounds of the type NXazbc, thenitrogen atom being a member of two rings, was observed.o-Xylylene bromide combines with 2-phenyl-6-methylpiperidine, andthe product may be separated into two isomerides, differing inmelting point and solubility, and yielding isomeric salts.Thesecompounds contain only a single nitrogen atom, and thus differfrom those previously obtained in isomeric forms from trimethylenebromide and dipiperidylethane, which contain two similarlysituated nitrogen atoms 9 :Hthe present compounds having the constitution :The case of compounds containing two asymmetric nitrogen atomshas been examined, in order to determine whether the same relationshold as in compounds containing two asymmetric carbon atoms.Thus, the compound :Ph, , PhEt \ /' Et Me> N*CH,*CH,*CH,*N =I / \Femight be expected to exist in two inactive and- two active modifi-cations, the former being respectively the racemic and the internallycompensated forms. The compound has, in fact, been synt,hesised in6 R.Meldola and H. Kuntzen, Trans., 1910, 97, 444.7 Ann. Report, 1909, 132.9 0. Aschan, Zeitseh. pltysikal. Chem., 1903, 46, 293 ; A., 1904, i, 350.M. Scholtz, Be?-., 1910, 43, 2121 ; A., i, 634ORGANIC CHEMISTRY. 93two different ways, and in each case the product is a mixture oftwo inactive isomerides.10 All attempts to resolve one of theseisomerides into its active components by crystallising the camphor-sulphonates or bromocamphorsulphonates, however, failed. Thefailure is of little weight as evidence against the racemic characterof the compound, as the resolution of inactive dialkylsuccinic,dialkylglutaric, and dialkyladipic acids has also never been accom-plished, and it is with these acids, rather than with the tartaricacids, that the nitrogen analogues are to be compared.Isomericdiquaternary ammonium salts of high molecular weight have not,so far, been isolated.TJhe Hantzsch-Werner Eypothesis.-The special form of stereo-isomerism postulated by Hantzsch and Werner in order to accountfor the observed relations of the isomeric oximes, and rapidlyextended to include the hydrazones and other compounds con-taining a :C:N* linking, has been accepted by many chemistswith a certain reserve, arising from the difficulty of formingany clear mental picture of the forces constraining themolecule to assume the supposed configurations. The same, oreven a greater, reluctance is felt to the extension of the hypothesisby Hantzsch to cover the diazotates and other compounds containingthe -N:N* linking.As regards the former class, however, no satisfactory alternative hypothesis has ever been proposed, the structuralisomerism assumed in certain specific cases being clearly inapplicablein others. The Hantzsch-Werner hypothesis thus holds the field,but a special interest attaches to all cases of observed or predictedisomerism which serve to put its validity to the test. An instance ofthis kind is found in compounds of the type Z>C:C:N*OH, themolecule of which has it plane of symmetry or not according as thethree valencies of the nitrogen atom lie in one plane or not.11Thus, whilst (I) is superposable on its mirror-image, (11) is not 12 :a t b a b\.,eO’C <> I* cAH\ /’’ 6/\IT.\d <‘>N\OR10 E. Wedekind and 0. Wedekind, Ber., 1910, 43, 2707 ; A., i, 834.11 W. H. Mills and Miss A. M. Bain, Trans., 1910, 97, 1866.l2 The thick lines represent valencies lying in front of the plane of the paper, andthe dotted lines valencies behind it94 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.As the practical difficulties of preparing such compounds wouldprobably be very great, the device already employed by Perkin andothers in the production of asymmetric moleculesl3 has beenadopted, namely, the substitution of the hexamethylene ring forthe ethylene grouping >C:C<. The required conditions are ful-filled in the oxime of cycZohexanone-4-carboxylic acid :H>(3<CH2*CH2>(3: N.()H :CO,H CH2* CH,and it is, in fact, found that this acid forms both dextro- andhvo-rotatory alkali salts, after resolution by means of morphine orquinine.The activity persists after conversion into the silver saltsand decomposition with sodium chloride. The possibility that theactive salts are really derived from a tautomeric form containingan asymmetric carbon atom is negatived by the chemical evidence,and the results lend considerable support to the view that the threevalencies of the nitrogen atom are directed along the edges of atetrahedron.A further interesting instance is afforded by the sernicarbazones,only very few of which have been definitely shown to exist in stereo-isomeric modifications. A careful study of camphorquinonesemi-carbazonel4 proves that two forms of this compound, mutuallyinterconvertible by heating under suitable conditions, may beobtained.Dimorphism and polymerism are excluded, whilst areview of the types of structural isomerism which might conceivablybe invoked to explain the differences shows that none of them areconsistent with the chemical behaviour of the whole of thederivatives. The isomerism, in fact, extends to the semicarbazones,the simple hydrazones and their acyl derivatives, and the phenyl-carbamylhydrazones, the relations between which are such as toadmit of no doubt that the isomerism of each pair must be of thesame kind. The fact that both hydrazones are obtainable fromdiazocamphor by reduction and are convertible into it by oxidationsupports the hypothesis of stereoisomerism :the chemical and optical properties of the hydrazones being incon-sistent with the assumption that one of them has the constitutionThe P-modifications are slightly coloured, and as colour isl3 Ann.Report, 1908, 106.l4 M. 0. Forster and A. Zimmerli, Tyans., 1910, 97, 2156ORGANIC CHEMISTRY. 95undoubtedly more likely to occur where there is a concentration ofunsaturated atoms, the syniconfiguration is assigned to the P-seriesand the anti-configuration to the a-series, thus :YHXI C=NC 8 H 1 4 < ~ ~a-Hydrazone, semicarbazone, &Hydrazone, semicarbazone,and phenylcarbamylhydrazone. and phenylcarbamylhydrazone.A very simple example of stereoisomerism of this kind occursin the chloroiminoketones. Whilst benzophenonechloroimide existsonly in a single form, p-chlorobenzophenone forms two chloro-imides :both of which react with hydrogen chloride to form p-chlorobenzo-phenonechloroimide, yielding p-chlorobenzophenoe and ammoniumchloride with water.Physical isomerism is excluded by the factthat each modification may be recovered unchanged after fusion ordissolution, whilst polymerism is excluded by the proof, in the caseof the derivatives from p-methoxybenzophenone, that both formshave the simple molecular weight.15Reference may also be made to two further instances that havebeen investigated recently. pLToluidine reacts with the k e bdichloride of p-chlorophenyl pchlorostyryl ketone, yielding twoisomeric arylimino-compounds 16 :C,H,Cl* g*CH:CH*C,H,Cl and C6H,C1 08 *CH:CH*C,H4C1C,€I,Me-N N*C,H,DleOne of these is colourless, and the other yellow, and two corre-sponding series of isomeric salts are formed, but it is not possiblea t present to assign the respective configurations to the twoisomerides.The matter is complicated by the fact that geometricalisomerism, due to the ethylene linking, although rejected by theauthors, is possible, and also by the occurrence of a third labilemodification under certain conditions.The second instance is that of the ethylidenesalicylamides, inwhich a great difference of stability between the syn- and anti-modifications is observed 17Me HI c <CO"OH H 6 4I .K < C O K FOH Me 6 4?In. anti.l5 J. Stieglitz and P. P Peterson, Ber., 1910, 43, 782 ; A., i, 323.l6 F.Straus and A. Ackermann, ibid., 696; A,, i, 241.l7 W. L. Hicks, Trans., 1910, 97, 103296 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.On the other side must be set the negative result of attempts toPh.5 *CH,PhN-Ph ' obtain stereoisomeric keto-anils.18 Deoxybenzoinanil,was only obtained in a single form, whilst phenyl a-naphthylPh*E *C10H7, yielded two modifications, differing in melting ketoneani I,point and crystalline form, but considered to be physical isomeridesfrom their identity of colour, solubility, and chemical behaviour.The stereoisomerism of simple azo-compounds has not hithertobeen observed, but two modifications of azobenzene are stated 19 tohave been obtained by distilling azoxybenzene with iron filings.Definite proof that the difference is one of stereoisomerism, andnot of merely physical isomerism, is at present lacking.N*PhSome Notiel Practical Methods and General Eeactions.In addition to the matter dealt with elsewhere, the followingunclassified observations should not be overlooked.When saturated hydrocarbons are nitrated, a considerable amountof oxidation usually occurs, the proportion of nitro-compoundsformed being greater the smaller the quantity or concentration ofnitric acid.On this observation is based a method in whichaluminium nitrate, Al(NO,),,SH,O, is used as nitrating agent ; thissalt melts at 7 3 O , and is completely hydrolysed at 140°, so thatbetween these two temperatures there should be a point a t whichthe free nitric acid attains the strength most suitable for thenitration of a given hydrocarbon ; cyelohexane in closed tubes at115-120° gives 56.7 per cent.of mononitro-compound, a yieldexceeding the greatest obtained by using free nitricSpongy copper, in presence of sodium hypophosphite, decomposeswater, liberating hydrogen, or, in presence of nitro-compoundsdissolved in alcohol, acts as a reducing agent, and in certain casestheoretical yields of amines are obtained.21 This reagent is usefulfor the preparation of aminophenols.Acid chlorides unite with many unsaturated open-chain andcyclic hydrocarbons in presence of aluminium chloride, the productsbeing P-chloroketones :R*CO*CI + 6:6 = R*CO*bk-Cl. . . . .l8 M. Busch and F.Falco, Ber., 1910, 43, 2557 ; A . , i, 747.' 9 C. V. Gortner and R. A. Gortner, J. A,naer. Chem. Soc., 1910, 32, 1294 ;2o S. S. Nametkin, J. Rztss. Phys. Chem. Soc., 1910, 42, 581; A., i, 829.21 A. Mailhe and M. Murat, Ball. SOC. chim., 1910, [iv], 7, 952 ; A , , i, 830.A., i, '190ORGANlC CHEMISTRY. 97Prom these ptoduCtR, unsa.tnrated ketones are obtained by theaction of amines.22Methyl and ethyl sulphates are now largely displacing the corre-sponding halogen compounds, being not only much cheaper, but alsomore reactive, compounds containing several amino- and hydroxy-groups often being completely alkylated by repeated treatment withthese agents, either alone or in presence of alkali.23 Even freeacid amides and their thio-derivatives unite with methyl sulphatebelow looo, yielding the methosulphates of the methylimino-ethers,from which sodium carbonate solution liberates the imin+ethers.24The preparation of nitriles by Lett’s method is improved by usinga, mixture of lead thiocyanate with the lead or zinc salt of the fattyacid; instead of lead thiocyanate, a mixture of lead ferrocyanideand sulphur may also be used, although in this case the yield is notquite so large.25When ketones of the formula O:CR,R:, are allowed to remain incontact with ammonia in alcoholic solution, and the liquid thenallowed to flow on t o metallic sodium, primary and secondaryamines, NH,*CHR,R, and NH(CHRIR&, are formed in consider-able quantities.The imino-compounds, NH:CR,R,, are probablyformed in the first instance, and subsequently reduced.Methyl-amine may be substituted for ammonia, and gives similar results.26Aldehydes, when acted on by anhydrides of carboxylic acids inpresence of sulphuric, hydrochloric, phosphoric, or oxalic acids atlow temperatures, are not converted into Semmler’s enot-acetates,but into the diacetates, R*CH(OAc),.27 The same appears to betrue of aldehydes having the formula CHR,R,*CHO, even i nabsence of mineral acids,2* and the enol-acetates of these can onlybe prepared from the a-glycols, OH*CRR’*C’H,*OH.A method employed by 0. Wallach 29 and his co-workers for thepreparation of Bydroxy-ketones and their derivatives from certainunsaturated hydrocarbons of the terpene series may suitably finda place here, as there seems reason to suppose that the method willbe a somewhat general one.The hydrocarbon (I) is first convertedinto its nitrosochloride (11), which is then heated with sodiumacetate dissolved in glacial acetic acid. In this way, an acetylatedB G. Darzens, Compt, red., 1910, 150, 707 ; S. Krapiwin, Bull. SOC. Imp&.NatzLr., I l l o k o u , 1908, 1 j G. Darzens and H. Rost, Compt. rend., 1910, 151, 758 ; ., i, 322, 349, 856.23 Compare R. Xeldola, Proc., 1910, 26, 232,W 141. Matsui, Mem. Coll. Sci. Eng. Kyoto, 1909-1910, 2, 37 ; A,, i, 695.26 1;. Ldffler, Ber., 1910, 43, 2031 ; A., i, 611.e7 R. Wegscheider and E. Spath, Honatsh., 1909, 30, 825 ; A., i, 825.m M. Tiffeneau, Compt. rend,, 1910,150, 1181 ; A., i, 379.29 Annnlen, 1910, 374, 217 ; A,, i, 569.E E.Reid, A7ner. Chem. J., 1910, 43, 162; A . , i, 169.REP.-VOL. VII, 98 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.oxime (III), or unsaturated oxime, may be formed, from whichhydrolysis generates the corresponding hydroxy-ketone (IV) orumaturated ketone respectively :c1 OAc OH(1.1 (11.1 (111.) w.)A new brominating agent, which may sometimes prove con-venient, is a solution of hypobromous acid, prepared by addingmercuric oxide and bromine alternately to cold water. Benzeneand benzoic acid are readily brominated by this reagent. Theobservation was made in examining the action of bromine on keto-dimethylpyrimidine, the perbromide being converted into sub-stitution derivatives by the actbon of water, an effect which wastraced to the intermediate production of hypobromous acid.30The generalisation, often quoted, that ap-unsaturated acids donot yield lactones when heated with 62 per cent.sulphuric acid, isnot without exceptions, as in certain instances they undergo isomericchange, and finally may be transformed quantitatively into lactonesof the corresponding saturated y-hydroxy-acids. This is the case,for example, with the P-methyl- and P-ethyl-pentenoic acids, whichyield the corresponding /3-alkylvalerolactones 31 :>C:CH- --+ >&c(:NoH)- >&c(:NoH) --+ >&co->o. EH*CO,H CH,*CO--CMe*CH,Me -+ hHMe*CHMeTwo new methods of preparing azoxy-compounds may be men-tioned. Azobenzene may be oxidised directly to azoxybenzene bymeans of hydrogen peroxide,32 and many amines may be oxidisedto the corresponding azoxy-compounds by a warm alkaline solutionof potassium t erricyanide.33 Anilinapsulphonio acid may beoxidised in this manner, yielding the compoundS03Na*C,H4*N,0*C6H4- S03Na.A further application of hydrogen peroxide is to the oxidation ofmonohydric phenols, the product being either a dihydric phenol ora quinone or a mixture of both compounds.The solution used mustbe a concentrated one, containing 30 per cent. of hydrogenperoxide .34Grignard’s Reaction.-The applications of Grignard’s reagent arenow so manifold that monographs devoted‘ t o the subject rapidlyfall out of date. I n addition to the case referred to under30 0. Stark, Ber., 1910, 43, 670; A., i, 234.y1 F.Fichter and E. Gisiger, ibid., 1909, 412, 4707 ; F. Fichter, A. Kiefer, and52 A. Angeli, Atti h?. Accad. Lincei, 1910, [v], 19, i, 793 ; A . , i, 645.35 F. Reitzenstein, J. pr. Chem., 1910, [ii], 82, 252 ; A., i, 702.34 GF G Henderson and R. Boyd, Trans., 1910, 97, 1659,W. Bernoulli, ibid., 4710 ; A , , i, 88ORGANIC CHEMISTRY. 99unsaturated compounds (p. 71), mention may be made of thereaction between acyl chlorides and magnesium pyrryl iodide, result-ing in the formation of ketones of the type :bORMagnesium phenyl bromide reacts with substituted anilides inthe following manner :C*Ph,*NEtPh C,H,*CO*NEtPh + Ph-Mg-Br =~ ) - M ~ * B ~ ?this compound being decomposed by water into benzophenone andethylaniline, but a second molecule of the reagent forms the stablecompound CP h,-NE tPh.36Remarkable differences are found in the triphenylmethyl seriesbetween the respective actions of magnesium phenyl chloride,bromide, and iodide.37 Magnesium alkyl compounds do not ingeneral react with phenyl ethers, but alkyl bromides, magnesium,and anisole or phenetole react together in benzene solution.%The reactions occurring between magnesium organic compoundsand various inorganic chlorides, etc., have also been studied.Onlyone atom in boron trichloride is replaced, and nitrogen chloridedoes not appear to react. Magnesium phenyl bromide and sulphurchloride yield phenyl disulphide, whilst thionyl chloride formssulphoxides 39 and sulphides.40Contact Actions of kfetals and Inorganic Substances,The employment of metallic oxidea at high temperatures ascontact materials for preparative purposes is still under investigation,and a, r6sum6 of the main results obtained with alcohols h a nowappeared .41The method may be used for the preparation of mixed as well assimple ketones42 and ether~,~3 both aliphatic and aromatic, and has35 B.Oddo, Ber., 1910, 43, 1012 ; A., i, 426.36 M. Busch and M. Fleischmann, ibid., 2553 ; A., i, 725.37 J. [Schmidlin, ibid., 1137 ; J . Schmidlin and J. Wohl, ibid.! 1145 ; A., i,a* V. Grignard, Compt. rend., 1910, 151, 323; A., i, 669.39 W. Strecker, Her., 1910, 43, 1131 ; A., i, 532.40 V. Grignard and L. Zorn, Compt. rend., 1910, 150, 1177 ; A., i, 532.41 P. Sabatier and A. Mailhe, Ann.Chim. Phys., 1910, [viii], 20, 289 ; A.,42 J: B. Senderens, Compt. rend., 1909, 149, 995 ; 1910, 150, 111, 702, 1336 ;a P. Sabatier and A. Msilhe, ibid,, 1910, 151, 359, 492 ; A , , i, 668, 669.H 2367, 368.i, 606.A., i, 11, 179, 318, 489100 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRP.various advantages as compared with the usual processes. Thiolsare obtained when the vapour of the corresponding alcohol, mixedwith hydrogen sulphide, is passed over heated metallicespecially good results being obtained with thorium oxide. Theprocess is a continuous one, and the presence of hydrogen as animpurity in the hydrogen sulphide has not much effect on theyields obtained. Primary alcohols react a t 300-360°, and aremore satisfactory than the secondary; with phenols, a higher tern-perature (430-480O) must be used, and the yield of thiophenolnever exceeds 17 per cent.The use of aluminium sulphate as an aid in the dehydration ofalcohols 45 possibly depends on a '' contact action " of some kind.The preparation of unsaturated hydrocarbons and ethers fromalcohols is greatly facilitated if about 5 per cent.of aluminiumsulphate is present in the sulphuric acid used as dehydrating agent;ethylene may be prepared from ethyl alcohol at 138O, whilst etheris formed rapidly a t 130O. Glycerol yields acraldehyde a t105-llOo in presence of anhydrous or hydrated aluminiumsulphate.46Metallic sulphides, and in particular cadmium sulphide, at320-330° cause a decomposition of thiols which is similar to thatproduced by metallic oxides on alcohols, dialkyl sulphides beingformed; a t 380°, more profound decomposition occurs, so thathydrogen sulphide and alkylenes are obtained.In order to explain the action of metallic oxides, such as thatof thorium or alcohol, it is suggested that a metallic alkyloxide isformed at an intermediate stage and subsequently decomposes.The equations given are as follows 47 :(1) Tho, + BC,H,,+,*OH = ThO(OCnH,,+I) + H,O.(2) ThO(OC,H,,,,), =Tho, + (CnH2n+,)20 (below 300O).(3) ThO(OC,H,,+,)2 = Tho, + 2C,H,, + H,O (above 300O).Numerous examples of the application of t'he reduction methodof Sabatier and Senderens48 are recorded, some of these being ofconsiderable general interest ; the temperature at which the nickelhas been prepared appears to have considerable influence on itsbehaviour, and this is of special importance when the substances tobe reduced are not easy t o separate from the products.Reference is made elsewhere in this report to experiments of44 P.Sabatier and A. Mailhe, Compt. rend., 1910, 150, 1217, 1569; A., i,45 J. B. Senderens, ibid., 151, 392 ; A., i, 649.46 J. B. Senderens, ibid., 530; A, i, 651.47 P. Sabatier and A. Mailhe, ibid., 150, 823 ; A., i, 294,4Ls G. Darzens, ibzd., 1999, 149, 1001 ; A., i, 63.456, 536ORGANIC CHEMISTRY. 101Henderson and others on the reduction of thymoquinol to menthane-diol, leading to a simple synthesis of a terpene, and also on thereduction of camphene and bornylene; the temperature used is here,as in other cases, of considerable importance.During reductions with hydrogen in presence of platinum-blackat low temperatures, the activity of the platinum is often found todiminish after use; in this connexion, H.Fournier 49 finds that theactivity of the metal may be restored by heating the latter for afew minutes a t looo. Working with ethereal solutions, this chemisthas reduced crotonaldehyde to n-butyraldehyde and the correspond-ing alcohol, the two safroles to their dihydro-derivative, and theisomeric eugenols to dihydroeugenol.Pinene is readily reduced by this method to a new hydrocarbon,C,,H,, ; limonene yields an inactive hydrocarbon, C1,H2,. Theproduct obtained from camphene is discussed in the section on theterpenes.Willstatter’s experiments on the application of this process to thepreparation of saturated amino-compounds have been extended tothe preparation of tropane from tropidine, and a-dimethylamino-pentane from dimethylpiperidine.The undiluted base gives thebest results in all cwes.50The use of colloidal palladium has been greatly simplified bymodifying the method employed in its preparation. In place ofprotalbic acid or lysalbic acid, which were formerly used as thecolloids needed to maintain the colloidal condition of the metal,gum arabic is used, and preliminary reduction of the palladiumsalt is not necessary. To the alcoholic solution of the substancewhich is to be reduced, aqueous solutions of palladiumchloride and gum arabic are added, care being takep that thesolution remains clear.Hydrogen is then forced into ,the solutionunder pressure, which may vary between 12 and 5 atmospheres.I n this way, pulegone is readily reduced t o menthone, with tracesof menthol, rnesityl oxide to methyl isobutyl ketone, and phoroneto diisobutylcarbinol ; oximes are reduced to amines, and aldehydesto alcohols.51 The method promises t o be among the most usefuland selective reduction processes which the organic chemist has athis command.Extended use is being made of small quantities of inorganicmaterials for the furtherance of certain reactions, which otherwiseare very slow or require very high temperatures. It is alreadywell known that the presence of small quantities of copper facilitates49 Bull.SOC. chim., 1910, [iv], 7, 23 ; A., i, 92.50 R. Willstatter and E. Waser, Bet-., 1910, 43, 1176 ; A., i , 366.51 A. Skita, d i d . , 1909, 42, 1627 ; A., 1909, i, 1627 ; A. Skita and H. Ritter,ibid., 1910, 43, 3393 ; A . , 1911, i, 71 ; compare also Ann. Bepart, 1909, 77102 ANNUAL REPORTS ON THE PROGRESS OF CHEMlSTRP.the interaction of aromatic amines with aromatic halogen com-pounds, and it has recently been ascertained that the displacementof the hydrogen in aromatic amines by metallic sodium occurs morereadily and at a comparatively low temperature if a, heavy metal,such as copper, or a salt of a heavy metal, is present.Synthesis of Hydrocarbons.-The subject of the direct union ofcarbon and hydrogen has received further attention. J.N. Pring 5 1 ~now admits the direct union of these elements with the formationof methane a t all temperatures above 1100O. The rate of unionand, particularly, the rate of decomposition of methane are bothtoo slow for equilibrium to be attained experimentally in theabsence of a catalyst. With the addition of platinum to the carbon,the equiIibrium is reached at 1200O and a t 1500O. Above thistemperature a rapid increase in the amount of methane occurs,owing to the decomposition of acetylene then formed in smallamount. Bone and Coward 52 have given details of further experi-ments showing a 95 per cent. conversion of carbon into methaneat 1150O. The carbon was mixed with 4 per cent. of its weight ofplatinum. Incidentally, they draw attention t o the improbabilityof Ipatieff’s statement53 that ethylene is formed when a mixtureof carbon monoxide and hydrogen is passed over coke mixed withreduced nickel, since 8 per cent.of ethylene in a gas mixture isstated not to be absorbed by either bromine or bromine water.The Or@inf of Petroleum.The mode in which paraffins and petroleum are produced innature has long been a favourite subject of controversy, and isperhaps not yet satisfactorily explained. The naphthenes, whichfrequently occur with these, and contain ring structures with asmaller proportion of hydrogen atoms, have been considered bysome to have their origin in the polymerisation of olefines, andAschan actually observed the production of naphthenes togetherwith “lubricating oil” when amylene is acted on by aluminiumchloride.The question of the process by which naphthenes areformed has recently been the object of further investigation, andhas been discussed at some length.54 The conclusion is drawn thatthese compounds are not produced by any simple polymerisationalone; polyolefines are probably formed in the first instance, andthese, owing to the presence of labile hydrogen, decompose intoTram., 1910, 97, 498, compare Pring and Hutton; ibid., 1906, 89, 1591,and Ann. Report, 1906, 73.52 Tram., 1910, 97, 1219.64 C. Engler and 0. Routala, Ber., 1910, 43, 388 ; C. Engler and B. Halmai,53 Ann. Report, 1909, 77.ibid., 397 ; C. Engler, ibid., 405 ; A., i, 160ORGANIC CHEMISTRY. 103paraffin, lubricating oils, and naphthenes. Amylene, with aluminiumchloride at low temperatures, gives compounds of the first two types,but when these are more strongly heated, the lubricating oils partlydecompose, giving naphthene.Amylene, heated under pressure,gives methane and hydrogen ; when left with aluminium chloridein the cold, it is converted very largely into an oil which in com-position and general character agrees closely with natural lubricatingoil, CnH2,,.-6. Engler has also discussed the origin of the varioushydrocarbons in nature, and suggests that the action of heat onpartly fossilised plant and animal remains leads to the appearanceof paraffins and olefines, which, under pressure, undergo more orless gradually the series of changes traced above. This accountsin a satisfactory way for the f a c t that natural oils, containing muchlubricating oil, are usually rich in naphthenes.A closely allied subject, namely, the pyrogenetic decomposition ofnaphtha, has also been investigated.55 The formation of aromatichydrocarbons is ascribed to the intermediate formation of acetyleneand its polymerides, and in agreement with this view it is found thatthe proportion of benzene formed from naphtha at high temperaturesis greatly augmented by the presence of those contact substances,such as iron gauze, which increase the speed of polymerisation ofacetylene.With reduced nickel, iron, or ferric oxide, pumice, etc.,at 600-700°, hydrocarbons, such as represent the main constituentsof naphtha or coal gas, are said to be very largely decomposed intohydrogen and carbon.A communication 56 on " The Volatile Constituents of Coal " willprobably attract general notice.The results may be summarisedas follows: (1) With all types of coal there is a well-defined pointlying between 700° and 800°, which corresponds with it markedincrease in the quantity of hydrogen evolved; this increase falls offin the case of bituminous coals above 900°, but it persists withanthracite coals up to 1100O. (2) Evolution of hydrocarbons of theparaffin series practically ceases a t temperatures above 700O. (3)Ethane, propane, and butane, with, probably, higher members of theparaffin series, form a large percentage of the gas below 450O.Attention is drawn t o certain technical developments which theresults foreshadow, but these points lie without the scope of thisreport.The authors make a further suggestion which is of a morepurely scientific kind, namely, that the temperature a t which thehydrogen increases in amount corresponds with the decompositionpoint of a substance common to all coals.55 I. von Ostromisslensky and T. Burschanadze, J. Rtsss. Phys. Ohem. Soc., 1910,56 M. J. Burgess and R. V. Wheeler, Trans., 1910, 97, 1917.42, 195 ; A., i, 309104 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.New Binary Carbon Compounds.When thiocarbonyl chloride, CSCl,, is mixed with nickel carbonyl,a fall in temperature is observed, while carbon monoxide, nickelchloride, and a brown solid are formed. The latter appears to bea polymeric form of carbon monosulphide, CS, and in certainrespects agrees in properties with the compound described by Sidotas a product of the decomposition of carbon disulphide by sunlight.A similar substance can be obtained by the action of ultra-violetlight on carbon disulphide at -SOo.A t the temperature of liquidair, and a t low pressures, carbon disulphide vapour, subjected tothe silent electrical discharge, yields a small quantity of a gaseousproduct which detonates violently when the temperature rises,yielding a brown deposit; the gaseous product is comparativelystable at high temperatures in presence of excess of carbondisulphide vapour. It is inferred that the carbon disulphide isdecomposed by the discharge into sulphur and a gaseous or veryvolatile endothermic carbon monosulphide, which polymerises withexplosive violence at temperatures slightly above the boiling pointof liquid air.57Carbon disulphide and nickel carbonyl in the liquid state do notinteract with appreciable speed, but when they are mixed in thestate of vapour, a change occurs at the ordinary temperature, andeven down to -8OO.The interaction increases in speed as thepressure decreases, aad thus resembles the oxidation of phosphorusand of aldehyde vapour in dry oxygen ; moreover, the change appearsto cease after a time. The latter effect is found to be due to carbonmonoxide, which is one of the products; it is suggested that nickelcarbonyl vapour is dissociated to some extent a t ordinary and lowertemperatures, the free nickel having a definite small concentration.As the equilibrium equation Ni(CO), t; Nict4CO indicates thatthe concentration of the free nickel in vapour of the carbonylshould be inversely as the fourth power of the concentration of thecarbon monoxide, it is evident that any time reaction in which thedissociated nickel takes part will be extremely sensitive to thepresence of excess of carbon monoxide,%Considerable general interest attaches to the discovery of a newcarbon subnitride, CpN2,59 which is prepared by removing theelements of water from the diamide of acetylenedicarboxylic acid,and therefore is probably the dinitrile of this acid (dicyano-57 Sir J.Dewar arid H. 0. Jones, Proa Roy. Soc., 1910, A, 83, 408, 526 ; A ., ii,408.Sir J. Dewar and H. 0. Jones, Trails., 1910, 97, 1226.59 C. Moureu and J. C. Bongrand, Comnpt. md., 1910, 150, 225 ; A., i, 159ORGANIC CHEMISTRY. 105acetylene), CN.CiC.CN. It has an irritating odour, resemblingthat of cyanogen, and is spontaneously inflammable at 1 3 0 O ; itsrefractive and dispersive powers are considerably larger than thosecalculated by the usual rules for a substame having the foregoingconstitution, and this is doubtless due to the conjugation of threetriple linkings.Nitroacetonitrile.At one period, fulminic acid was represented by almost universalconsent as nitroacetonitrile, NO,-CH,*CN, a view first suggestedby KekulB mainly in explanation of the ease with which mercuryfulmina-te was converted by chlorine into trichloronitromethane,cyanogen chloride, and mercuric chloride.The synthesis of nitro-acetonitrile, after innumerable unsuccessful attempts by variousinvestigators, has recently bee2 accomplished, and this result, wereit for its historical associations alone, can hardly fail t o awakena very general interest.The end was attained by removing the elements of water frommethazonic acid, C2H,0,N,. The latter, which is a product of theinteraction of hydroxylamine and sodionitromethane, yields potqsiumnitroacetate with aqueous alkalis, and is almost certainly sywl3-nitro-acetaldoxime, NO,*CH,*CH:NOH ; by the action of thionyl chloliidein boiling ethereal solution, it is converted into nitroacetonitrile,NO,*CH,-CHZNOH -+ NO,.CH,.CN + H,O.It is hardly necessary t o say that the product has none of themost characteristic properties of fulminic acid, but exhibits thereactions of a primary nitro-compound when subjected t oKonowaloff’s test or when treated with nitrous acid, which convertsit into cyanomethylnitrolic acid.The presence of the cyano-groupis proved by the transformation of the substance into nitroethenyl-amido-oxime, NO,*CH,-C(NH,):NOH, with hydroxylamine, andinto nitroacetamide by means of hydrogen chloride in methylalcohol.Carbohydrates and their Allies.I n extension of electrolytic investigations on the supposedreversibility of the sugar synthesis discussed in the report for lastyear (p. Sl), the produch obtained by the action of the hydroxidesof lead and of sodium on aqueous sugar solutions have beenexamined ; the substances isolated or identified include form-aldehyde, pentoses, acetylcarbinol, acetylmethylcarbinol, and poly-hydroxy-acids.This is held t o confirm the view that the syntheticformation of sugar is of a reversible character ; further, it is inferredthat gentoses are intermediate phases in the synthetic process.Degradation of sugar to formaldehyde and pentose appears to occu106 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in solutions which have an alkalinity corresponding with that ofthe blood.60It is interesting that laevulose, but not aldoses, undergoes profoundchange when their aqueous solutions are subjected to the influenceof ultra-violet light, formaldehyde, methyl alcohol, and oxides ofcarbon being among the products obtained.61An electrolytic method has been used for passing from one aldosehaving n carbon atoms t o one having n- 1 carbon atoms.Thealdose is converted into the corresponding acid, which is thenelectrolysed :OH*CH,*[CH*OH],*CH(OH).CO,H -j OH*CH,=[CH*OH],*CHO,and all the steps in the degradation of glucoheptose to formaldehydemay be traversed.d-Galactonic acid, by this process, was converted into d-lyxose,d2-erythronic acid into dZ-glyceraldehyde, glyceric acid into glycoll-aldehyde, and glycollic acid into formaldehyde. Aminohydroxy-acids, such it9 isoserine, appear to undergo a similar change.62A lengthy treatise on the action of alkalis on sugars is hardlysuitable for full discussion in the short space which can be devotedto it here, although, like all communications from the pen of itsauthor, it bristles with interesting experimental and theoreticalpoints.The suggestion is made t4hat hexoses are never formed bya synthetic process from pentoses and formaldehyde, a view whichis in striking contrast to that expressed by Lob and Pulvermacher,referred to above; the formation of these two substances from ahexose has never come under the author's observation, the normalproducts being either diose + tetrose, or two molecules of glycer-aldehyde.In certain cases, as, for example, with pentoses, it is suggestedthat an a@-dienol is formed, OH*CH:C(OH)*(C'H*OH),*CH,*OH ;this is resolved into a tetrose and the hypothetical hydroxy-methylene, OH*CH:, which then condenses to the dienol,OH=CH:CH*OH, from which glycollaldehyde is formed.Tetrosesyield only 2 : 3-dienols, and thus give rise to two molecules of dioseand no triose; the same is supposed to hold with mannose, dextrose,and laevulose.The author's theory of bivalent carbon is thus introduced in amost ingenious manner, but this application of it, in conjunctionwith the great disparity in properties assigned to pentoses on thebo W. Lob and G. Pulvermacher, Bwchenc. Zeitsch., 1909, 23, 10 ; 1910, 26, 231 ;61 H. Bierry, V. Henri, and A. Ranc, Compt. rend., 1910, 151, 316 ; A., i, 652.82 C. Ncuberg, L. Scott, and S. Lachmann, Bwchem. Zsitsch., 1910, 24, 152;A., i, 95, 609.A., i, 218ORGANIC CHEMISTRY.107one hand, and to hexoses and tetroses on the other, conveys theimpression that an equally good explanation of the facts might bedeveloped on more orthodox lines.63The aldehexoses are oxidised by hydrogen peroxide in alkalinesolution, the products being very different from those which areformed when air, Feliling's solution, or mercuric oxide is used asoxidising agent; in the latter instance, as was shown by Nef,64 thesubstances obtained and their relative proportions are the same ineach case. With hydrogen peroxide, dextrose and laevulose yieldonly formic acid, carbon dioxide, glycollic acid, and a-hydroxy-methyl-d-arabonic acid (I) ; galactose yields the first three of these,with a-hydroxymethyl-d-lyxonic acid (11).CH,*OH OH OH CH,*OH H OHOH H H H 6H HCO, H* 6 --- S~---~CH,-OH CO~H-~---~-- ~CII,.OH(1.) (11.)These products are considered to be formed by the selectiveoxidation, in the alkaline sugar solution, of formaldehyde, glycoll-aldehyde, " a- and P-d-glutose " (from dextrose and Izvulose) pro-OH*CH,*d-CO*d-c'- CH,*OH OH C H,*'C-CO- c-k C H 2- O HOH OH O H H OH OHH H H b H H H(U-Glutose.) (B-Glutose.)duced from the original sugars by the alkali. I n the case ofgalactose, the isomerides oxidised must be a- and P-galtose.The production of hydroxymethylarabonic acid from glutose isassumed to be due to an intramolecular change (analogous to thebenzylic acid transformation) in the osone, which is the primaryoxidation product :OH*CH,*CO*CO*CH(OH)* -+ CO ,~e,Hz>C(OH)-CH(OH)~ H--A re-examination of the acids obtained by oxidising dextrose andlzvulose with hydrogen peroxide, in the presence of ferrous sulphate,makes it appear probable that previous observers were mistaken insupposing erythronic acid to be formed ; formic, carbonic, and oxalicacids were isolated, and the remaining acids appeared t o be ketonicin character.The large quantity of oxalic acid produced isattributed to hydrolysis of polyhexosones, such asCHO*@O*CO*C,0~CH(OH)*C€€2~OH.~~The Mode of Condensation of Acemtone m*th Fructose.-It has63 J. U. Nef, Annalen, 1910, 376, 1 ; A., i, 711.65 H. A. Spoehr, Amer. Chem. J., 1910, 43, 227 ; A., i, 221.AnnuZen, 1907, 357, 214 ; A . , 1908, i, 5108 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.previously been shown that the aldol-like condensation products ofacetone with lzvulose consist mainly of a- and P-fructosediacetone,and that in the former of these a t least the CH,*OH group remotefrom the “ ketonic ” group of the kevulose molecule is intact.66 Thelatter characteristic is shared by the fructosemonoacetones, whichhave now been isolated.Assuming that the rings present in allthese compounds are of the five-membered type, CBlez<o.h. 7 thenew compounds must have the constitutions ( A ) and ( B ) ; no sub-stance of the third possible type (C) has been detected:0-c:CH,*O CH,*OH C H;OHI >CMe, I &*OHlL;-O>CMe, CH-00 l - h * O I >CMe, 0 1UH*OH CH-0J--CH I IIt is concluded that the fructosediacetone is formed exclusivelyfrom A , for the acetone residues in fructosediacetone are found inthe positions separately indicated in A and C respectively; thecompound B is evidently not prone to further condensation, aconclusion consistent with the view that the acetone, )CMe,, residuereplaces the hydrogen atom of two adjacent hydroxyl groups.67The mutarotation of the polyhydroxy-acids derived from thealdoses has recently been studied, and it is suggested that this maybe utilised as a means of identifying the acids of the sugar group.A freshly prepared solution of arabonolactone has [a]D about - 70°;the rotatory power changes and becomes constant a t [.ID - 5 1 * 5 O ,a value identical with that which galactonic acid finally attains inaqueous solution, though originally it has [a]= - loo.Gluconic,galactonic, saccharic, and rhomnonic acids and their lactonesexhibit characteristic changes of the same type.68Employing the synthetic method described in last year’s report 69for the preparation of disaccharides, a step towards the artificialproduction of a tetrasaccharide has been made. Bromoacetomaltosewas shaken with dry silver carbonate in chloroform, when a sub-stance, having the composition C~,H,~O,(OAc),,, of a tetrademacetyldisaccharide was produced and isolated ~ t s an indistinctly66 Compare Ann. Report, 1909, 81.67 J. C. Irvine and C. S. Garrett, Tmns., 1919, 97, 1277.A8 K. H. Boddener and B. Tollens, Rer., 1910, 43, 1645 ; Zeitsch. Yer, dezrt.Zzdmrind, 1910, 727 ; A., i, 460.69 Ann, Report, 1909, 82ORGANIC CHEMISTRY. 109crystalline powder ; on hydrolysis, however, it wm partly resolved,but there was present in the product a non-reducing carbohydrateof high molecular weight, probably the free tetrasaccharide. Thispaper also contains an interesting account of the preparation ofmenthylmaltoside and other synthetic “ glucosides.” 70The Constitution of the BenzelEepotycarboxylic Acids.Attention may here be directed to a communication of muchimportance 71 on this subject. The constitution assigned to numerousproducts obtained from terpenes and other ring compounds dependson the identification of their degradation products, among whichare not infrequently found compounds such as the trimethylbenzene-carboxylic acids, and the structure of these, as well as that of therelated benzenetetracarboxylic acid, is for the first time placed ona sound experimental basis. “Prehnitic acid” is shown to be1 : 2 : 3 : 5-benzenetetracarboxylic acid, whilst “ mellophanic acid ”is the corresponding 1 : 2 : 3 : 4-compound.The interchange of theformulz assigned to these two acids is justified, first, by the synthesisof the former from bromomesitylene, magnesium and carbondioxide in ethereal solution, and the preparation of the latter byoxidation of 1 : 4-dimethylnaphthalene ; moreover, the behaviour ofthe two acids, when subjected to dehydration or esterification, is notin harmony with the old view of their structures, but is in no wayat variance with t.he formula: now proposed.Curb o n Ring Formtion.It is well known that y-ketonic carboxylic esters contain a *CH2*group directly attached to the carbonyl group, and yield derivativesof 1 : 3-diketocyclopentane (3-hydroxycyclopentenone) on treatmentwith sodium or sodium alkyloxides ; similarly constituted 8-keto-carboxylic esters yield derivatives of dihydroresorcinol.It hasrecently been found that E-ketocarboxylic esters of the type (I) areconverted into 2-acylcyclopentanones (11), and not into derivatives ofdiketocycloheptane (111) :7H,*CH,=CO2E t $!H,---CH,>co vH2* CH,*COCH,*CH,*CO*CH, CH,-CHAc CH,* CH,*CO >CH,~ (1.) (11.1 (111,)l-Ketonic esters may give cyclohexanones, but never diketowdo-octanes, whilst 7-ketonic esters do not yield cyclic compounds atall.72 Thus, the Dieckmann reaction is apparently not applicable70 E.Fischer and H. Fischer, Ber., 1910, 43, 2521 ; A., i, 716 ; compare, also,E. Fischer and G. Zemplh, ibid,, 2536 ; A . , i, 718.71 Miss H. Bamford and 5. L. Simonsen, Tmns., 1910, 97, 1904.72 E, E. Blaiao and A, Koehler, Bull. SOC. chim., 1910, [iv), 7, 710 ; A , , i, 626110 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.to the formation of rings other than those containing five or sixcarbon atoms.A very remarkable compound, which from its mode of preparationwould seem t o be diethyl cycloundecane-1 : 1-dicarboxylate :has been obtained by the action of ao-dibromodecane on ethyl sodio-malonate.73 Whilst the existence of such an eleven-carbon ring isnot a t variance with Baeyer’s strain theory as applied to van’t Hoff’sconception of the carbon atom and its complexes, yet no compoundcontaining a ring of this magnitude and without a “ bridge ” haspreviously been obtained.Isomeric changes, leading to theformation of smaller rings in similar cases, are not quite unknownamong nitrogenous compounds, and such a possibility in this casedoes not yet appear to have been entirely eliminated. Hardly lessremarkable than the foregoing substance, if the constitution assignedto it be accepted, is another ester which has been described duringthe year.74 It may be obtained from ethyl sodiocarboxyglutaconicester by the action of iodine and in other ways; it is considered t opossess the following structure, and in accordance with Baeyer’snotation it is named, by its discoverers, ethyl 2 : 2: 4 : 4-tetracarboxydicyclo-011-butane-l : 3-dimalonate :A number of its derivatives have been prepared, all of which canbe formulated on similar lines.Carbon Ring Stability.I n the report of last year, reference was made to one or twoinstances in which apparently small alteration in the groups to aclosed carbon chain had been found to alter profoundly the stabilityof the cyclic arrangement of atoms. 0.Wallach had previouslydiscussed certain changes of this kind,75 in connexion with thebehaviour of thujyl alcohol (I) and sabinene hydrate (11), the formerof which is not affected when shaken with dilute sulphuric acid,whilst the latt,er is converted first into Al-p-menthen-4-01 (111), andthen into p-menthan-1 : 4-diol:73 A.Franke and 0. Hankam, Monnts?b., 1910, 31, 177 ; A., i, 460.74 M. Guthzeit and E. Hartmann, J. pr. Chem., 1910, [ii], 81, 329 ; A . , i, 386.75 Annalen, 1908, 360, 83; A . , 1908, i, 429ORGANIC CHEMISTRY. 111CPrP CPrPOH PrpC\/CPrpCH,//\CH, CH,y\CH, CH2/yH, CH,//)CH,CH!,)CH~OH CH(,!!CH, CR(\,CH, C!\,CH,c: C UMe CMe/\OH Me/\H Me(1.1 (11.) (111.) UV.1In explanation of such observations, it was suggested that thepresence of a quaternary carbon in a ring leads to decreasedstability, and in the foregoing instance dehydration of (11) wouldfirst yield a hydrocarbon having the constitution (IV), in which thequaternary carbon atom probably determines the instability of thecyclopropane ring.A similar explanation has been given 76 for thebehaviour of a-thujadicarboxylic (V) and a-thujaketonic (VI) acids.Ketones enolise far more readily than do carboxylic acids, so that(VI) may afford the isomeric enolic form (VII) under conditionswhere (V) would not be affected to any appreciable extent. Thecyclopropane ring in the enolic form (VII) conforms to the abovecriterion of instability, and, in harmony with the theory, B-thuj*ketonic acid (VIII) is produced:CPI 6 CPrF CPrp PPr@ CH,/’\CH, /\cH, CH,/\CH, CH, NCHCH CH C CH2I/ d0,H 77 d0,H I/ 60,H 1\CO,H \COMe b M e * O H ‘COMe(V.1 (VI. 1 (VII.) (V 111. )The insbbility of pinonic acid (IX), as contrasted with pinicacid (X), can be accounted for on precisely similar fines :CH-COMe CH*CO,E€CH*CH,*CO,H CH*CH,* CO,H60,HCMe,()CH, CMe,<)C H,(IX.1 (X- 1This explanation has already been adversely criticised, snd itcertainly does not appear to be applicable in all cases.77As illustrating the apparent stability in certain cases of the four-carbon ring, as contrasted with that of the threecarbon ring, thecase of the condensation of ethyl sodiocyanacetate with ethyl l-cyano-77 G. Cusmnno, Atli B. Aced. Lincci, 1910, [v], IS, ii, 63 ; A,, i, 686.D. Thomson, Trans., 1910, 97, 1502112 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.cyclobutane-l-carboxylate (11) may be cited. Under conditionswhere the corresponding cy clopropane derivative (I) yields an open-chain cornpound (111), the cyclobutane compound is atstacked inthe side group, yielding the imino-compound (IV) 78 :YH 2*CH( CN ) CO,F,tCH,*CH(CN)* C0,Et CH,*CH,~H,*~(CO,Et) *C( NH)* CH(CN)*C'O,Et(111.) (IV.1Oxonium and Carboniurn Compounds.Towards the end of last year, and too late for inclusion in thereport for 1909, an important paper 79 appeared, in which the viewwas put forward that a large number of compounds, generallyconsidered as oxonium salts, should be regarded as carbonium com-pounds. Starting from the hypothesis adopted by Gomberg andCone 80 to explain the behaviour of triphenylchloromethane andanalogous substances, that these compounds are capable of existingin two isomeric modifications, the one aromatic and colourless (I),and the other quinonoid and coloured (11) :(1.1 (11.)these authors assign the " quinocarbonium " structure (11) to anumber of derivatives, many of which contain oxygen.The carboxonium salts, such as those derived from xanthenol,triphenylcarbinol, or benzo-y-pyranol, are always described ascoloured substances.It is shown, however, that the method ofisolation is always such that only the quinonoid form would beobtained, even if two modifications were capable of existing. Thecolourless carbinol dissolves in acids to form a coloured solution, andit coloured ferrichloride may be precipitated, but it cannot beconcluded from these facts that the solid carbinol chloride wouldbe coloured. On the contrary, colourless triphenylcarbinol chlorideis capable of forming a coloured solution in liquid hydrogen chloride,whilst its colourless methoxyl derivatives yield intensely colouredcompounds with hydrochloric acid.The suspicion, that the colour is only developed in the presenceof an excess of acid or of a haloid salt, is confirmed by experiment.7s A.F. Campbell and J. F. Thorpe, Tyant., 1910, 97, 2418.79 M. Gomberg and L. H. Cone, Annalcn, 1909, $70, 142 ; A., i, 55.80 Ann, lieport, 1907 116ORGANIC CHEMISJ'RY. 113If xanthenol is dissolved in an indifferent solvent, and hydrogenchloride is passed into the solution, an intensely yellow precipitate isobtained, composed of 1 mol. of xanthenol chloride and 1 mol. ofhydrogen chloride. When this hydrochloride is suspended in anindifferent solvent, this mol. of hydrogen chloride may be removedby a current of air, and the resulting xanthenol chloride is colour-less.The reactions of these colourless chlorides completely resemblethose of the triphenylcarbinol chlorides. Even the preparation oftriphenylmethyl finds its parallel in the action of silver on phenyl-xanthenol chloride, a dark red solution being obtained, which -readily absorbs oxygen, precipitating the colourless phenylxanthenolperoxide, [O<C~H4>CPh*],0,.Cfs.4Further, the xanihenol chlorides dissolve in liquid sulphur dioxideto coloured solutions, the quinonoid constitution of which is sup-ported .by the fact that when the compound taken is the chlorideof a p-bromederivative, it is always possible to recover a bromideof the p-chloro-derivative from the solution.Hydrogen chloride iscapable of bringing about the same change in benzene solution,whilst the change II- I11 is produced even by silver chloride atthe ordinary temperature :0 0&/\/\ so2 B U N / \ AgClCGH4 -+ C1'( I CCH4 -+HCl \/\/ HCI (A/ c CA.C1 P h(1.)IYh(11.10 0$h(111.)this transformation being exactly similar to that observed in thesubstituted derivatives of triphenylmethyl chloride.81Complete similarity is observed between the sulphates, doublesalts, and perchlorates of the xanthenols and of the triphenylmethylcompounds, and as oxygen is absent from the latter, it is consideredunnecessary to assume an oxonium structure for the former. Theargument is extended to the pyranols, and also to the derivativesof acridine, a very large number of compounds being studied in eachclass.The case of the acridine compounds is particularly interest-s1 Ann. Beport, 1907, 116.REP.-VOL. VII. 114 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ing. The basic properties of the phenylacridols are generallyattributed to the presence of the “bridge” nitrogen. 5 : 10-Di-phenylacridol is, however, a, derivative of triphenyl-amine, the basic properties of which are so weakthat only two salts, a hydrofluoride and a hydro-/\/\/\ bromide, the latter existing only a t a low tem-I I 1 1 perature, have been isolated. The complete \”‘”’ resemblance of 5 : 10-diphenylacridol in its colourto regard this, and probably all other acridols, asforming quinocarbonium salts.Against this view, Hantzsch82 has objected that the colouredphenylmethylacridol salts have a high conductivity, comparable withthat of the quaternary ammonium salts, and inconsistent with acarbonium structure.The objection has, however, been removed inthe meantime by the observation83 that the dimethyl ether offluorescein ester, which does not contain nitrogen, yields a chloride,the conductivity of which is of the same order as that of phenyl-methylacridol chloride.I n a later paper by Gomberg and Cone,s4 the experiments areextended t o thioxanthenols, with similar results, and a number ofapplications of the quinocarbonium hypothesis are made, in par-ticular the influence of such substituents as hydroxyl and theamino-group being studied.Further, the salts of dimethylpyroneare brought into line with those of the other classes mentioned. Itis considered doubtful whether alcohols and phenols ever yield saltswith acids in definite stoicheiometric proportions, and the salts ofketones are regarded as being formed by the addition:Ph\/C7 Ph reactions, etc., t o the xanthenols leads the authors>C:O + HX =>C<$H.I n the same way, dimethylpyrone may be considered to react withacids by virtue of its carbonyl group, addition taking place to forma carbonium salt. The behaviour of picric acid towards hydrogenchloride in solution has also been explaineds5 by the formation ofThe principal opposition to the wide extension proposed to begiven to the class of carbonium salts has come from Kehrmann,*682 Ber., 1910, 43, 339.83 F.Kehrmanii, Annalen, 1910, 372, 328 ; A , , i, 406.A,nnalen, 1910, 376, 183 ; A., i, 869.*t5 A. Stepanoff, ibid., 373, 219 ; A , , i, 471.*6 F. Kehrmana, ibid., 372, 287 ; A., i, 406ORGANIC CHEMISTRY. 115who, whilst adopting a quinocarbonium structure in many instances,considers that there is no justification for assuming that all “onium”salts are constituted similarly. The chlorides of phenylxanthenolare formulated thus :Ph C1Ph Ph \/6/\ a c‘1c;0bColoured. Colourless.As regards the derivatives of acridine, the fact that acridiniumsalts closely resemble the phenylammonium salts in poisonous pro-perties, taste, etc., is adduced in favour of the attachmnt of thehydrogen chloride to nitrogen.A further impetus has been given tp the study of carbonium andoxonium compounds by the introduction of a new reagent.Thisis a concentrated 71 per cent. solution 04f perchloric acid, which formshighly crystalline? sparingly soluble salts, and has a remarkablecapacity for combining with compounds possessing only weak residualaffinit~.~7 Triphenylmethyl chloride and perchloric acid react a tonce, hydrogen chloride being liberated. The study of the con-ductivity of these perchlorates in indifferent solvents gives interestingresults.88 The solution of triphenylmethyl perchlorate in tetr&chloroethane is coloured, and conducts electricity, although thissolvent is unable to render the corresponding chloride conducting.The solubility in a series of solvents follows the same order as thatof mercuric chloride, whilst it is quite different from that of sulphur,thus illustrating the close analogy between carbonium salts andmetallic salts, an analogy which is particularly well marked in thedinaphthapyryl salts, (O<c10H6>CH*)X, C H 89 which react in solutionlike the salts of a metal, the sulphide being precipitated by hydrogensulphide, the picrate by potassium picrate, etc.Perchloric acid has been utilised in the investigation of a compoundformerly90 obtained from the product of the action of methyl10 687 K.A. Hofmann and collaborators, Ber., 1909, 42, 4856 ; 1910, 43, 178, 1080,88 K. A. Hofmann, H. Kirmreuther, and A. Thal, ibid., 183 ; A . , i, 168.89 R.Fosse, Compt. rend., 1909, 148, 1607 ; Bull. SOC. chim., 1909, [iv], 5, 692,go F. Kehrmann and A. Duttenhijfer, B e y . , 1906, 39, 1299 ; A., 1906, i, 447.2624; A., i, 105, 187, 370, 818.787,790, 797 ; A., 1909, i, 599, 666, 667, 734.1 116 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.sulphate on dimethylpyrone, and then regarded as an oxoniummethiodide. The perchlorate reacts with ammonium carbonate toform methoxylutidine, leading to the assumption of the constitutionO-SO,Me, for the product with methyl\/OMeuative carbonium structure is not discussed.sulphate.91 The alter-Terpenes and Allied Compounds.I n this section of carbon chemistry, many clear-cut advances havebeen made during the last few years both by analytic and bysynthetic means, but the constitution of camphene, among the lesscomplicated representatives, remains uncertain, and the synthesisof the dimethylcy clobutane complex of pinene and its degradationproducts has not yet been achieved.The constitution of certainsesqui- and poly-terpenenes, of cholesterol and its relatives, and ofcaoutchouc, are also outstanding, problems to which attention is beingdevoted.Gamphene and Borny1ene.-The isomeric borneolls (I), or thecorresponding bornyl halides (pinene hydrochloride, etc.), when con-verted into hydrocarbons by the removal of water or halogen hydride,yield mainly either camphene or bornylene, or both, according tocircumstance. Bornylene is known to be the normal product (11), asit yields the same products of oxidation as borneol itself, namely,camphoric acid. The properties of camphene cannot be explainedby such a formula, but after long discussion, a way indicated in lastyear’s report, Wagner’s formula (111), is now regarded with muchfavour; C.Harries and J. Palm& 92 have since published theresult of their investigations on camphene ozonide, which serve tostrengthen the case in its favour.Dimethylnorcampholide, which is certainly represented by (V),appears t’o be formed by the normal isomeric change of an inter-mediate perozonide (IV) ; a transformation of the pinaconepinacolin type is therefore assumed to occur during the formationof camphene from bornyl derivatives :CH,-CH-CH, CH,-CH--CH CB,-CH*CMe2CH,-CMe-CH*OH C€€,*bMe* CH CH,-CH*C:CH2(1.) (11.) (111.)I I I I YMe2 i 1 CMe, lj 1 CH,/ I91 A.v. Baeyer, Ber., 1910, 43, 2337 ; A., i, 763.92 Uer., 1910, 443, 1432; A , , i, 497ORGANIC CHEMISTRY. 117OH,-CH-CMe, I I CH2-CH-CMe, CH,--UH,-CR, 1 bH, bCH,*CH-CO CH,--CMe-CH, I ICamphene and bornylene thus contain quite different nuclei, anddo not differ, for example, merely in the position of a double linking,and this point has been confirmed in an interesting manner by thecomparison of their dihydro-derivatives, which can be obtained bythe contact method of reduction devised by Sabatier and Senderens.93Thus bornylene readily yields camphane (VI), which has alreadybeen obtained by Aschan by the reduction of bornyl iodide.Camphene is reduced with more difficulty, and yields a dihydrecamphene which is identical with the substance obtained by Vavon94on reducing camphane with hydrogen in presence of platinum-black,and is quite different from camphane.The evidence in favour of Wagner’s formula for camphene is notquite conclusive.Certain important products obtained by oxidisingcamphene are not readily accounted for by the aid of that structure,but are easily explained by means of (VII), which is closely alliedto the former 95 :CH2-CH-CMe2 1 dH2 bH .I II GI?,-CH-CH(VII.)Simple oxidation products of (VII) might readily undergoisomeric change of the type associated with the (‘pinacone” or“ benzylic acid ” transformations, and yield products derived fromthe carbon complex of (I); thus the glycol or ozonide from (VII)might become converted int’o camphenilanaldehyde,gg and the corre-sponding diketone (IX) into camphenylic acid (VIII) :CH,-CH-CMe, CH,-CH-CMe, G‘H,-CH--CMe,+- 1 &H2 60 -+ 1 b H , 1’0,HCH,-CH-GO CH,-CH-CO,H(VIII.) (IX.1 (X.)Nearly 70 per cent.of the product obtained by oxidising campheneconsists of camphenic acid (“ camphenecamphoric acid ”), for whichthe most satisfactory structure is (X). It is certainly an active,saturated dicarboxylic acid, containing only one )CH*CO,H group,93 G . G . Henderson and E. F. Pollock, Trans., 1910, 97, 1620.94 G . Vavon, Compt. remi., 1909, 149, 997 ; A,, i, 52.95 0. Aschan, Annulen, 1910, 375, 336 ; A., i, 709.g6 Compare Ann. Report, 1909, 92.II I I I YH2 I CHz-CH-C(OH)*CO,118 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.which may be converted into )C(OH)-CO,H by the successiveactions of bromine and dilute alkali; the resulting hydroxy-camphenic acid does not form a lactone, and on fusion withpotassium hydroxide yields isobutyric, succinic, and oxalic acids.Wagner considered that the camphenic acid was it secondaryproduct from camphenylic derivatives, but as it is found that thelatter cannot be converted into camphenic acid the suggestionappears to have no very sound experimental basis.97Caoutchouc.-The formation of a substance like caoutchouc fromisoprene by the action of aqueous hydrochloric acid was noted forthe first time by Bourchardat,98 although Williams,99 as early as1860, recorded the fact that isoprene becomes viscid when exposedto air, and spongy products are left when the sticky mass is distilled.Tilden,l in 1882, published the results of experiments which con-firmed Bourchardat’s observation, and drew attention to the factthat the polymerisation also appears to be brought about by theagency of nitrosyl chloride. In 1902, Tilden adduced evidence ofthe most convincing character that the product obtained fromisoprene by slow spontaneous polymerisation has all the propertiesof t3he natural rubber ; it is only recently, however, that this synthesisof caoutchouc has been acknowledged as a fact beyond dispute, andthe substance has now been prepared from isoprene by severalmethods, although the synthetic article.has not appeared on themarket among the numerous substitutes for the natural material, forisoprene itself it still something of a chemical curiosity.Harries found that ozone converted caoutchouc into di-ozonide,which had the composition and molecular weight corresponding withthe formula C10H1606, indicating that a very substantial dipoly-merisation occurs during combination with the agent, the moleculeof the product corresponding with only a doubled isoprene molecule.The formula proposed for the ozonide by Harries:> 0 3 9CMe*CH,*CH,*FH03<b€€-CH2-CH,-CMereadily accounted for the laevulinaldehyde obtained from it bytreatment with water, and led t o Harries’ formula for caoutchoucitself, namely :;Me*CH,* CH2*fiH (E CH-CH,-CH,-CMeSynthetic rubber from isoprene yields a “ tetrabromide ” and97 0.Aschan, loc. cit.93 Compt. rend., 1879, 89, 1117 ; A., 1880, 323.99 Proc. Roy. SOC., 1860, 10, 517.1 Chcm. News, 1882, 46, 120 ; Brit. Assoc. lieport, 1882 ; A,, 1883, 75ORGANIC CHEMISTRY. 119“ nitrosite ” apparently identical in all respects with those of thenatural hydrocarbon.2Pickles has criticised the formula proposed by Harries, pointingout that the polymerisation of the simple dimethylcyclooctadieneunit conceived by Harries must be either chemical or physical inkind. I n the former cme, the polymeride would be less unsaturatedthan the unit, which is not the case, for the bromide contains fourbromine atoms for every ten atoms of carbon, but its molecule isstill highly complex, perhaps not less so than that of caoutchoucitself. Were Harries’ formula correct, it would thus be necessaryto suppose that the complex molecule of the tetrabromide is a stableaggregate of saturated molecules :r--CH2* CH,*CMeBr ) xCMeBr*CH2* CH,* YHBr(aKBfor which no analogy exists.Other reasons are adduced for reject-ing Harries’ formula, and an alternative one is proposed, in whichthe caoutchouc molecule is assumed to be constituted as a strictlychemical aggregate of isoprene residues, ( :CMe=CH,*CH2*CH:),.This at once accounts for the formation of the bromide and nitrositewith large molecular weights; to explain the formation of theozonide, the interesting suggestion is made that ozone causesseparation of the two doubly linked carbon atoms.The ozonidewhich results may therefore be formulated as containing, in placeof the >C:C< group of the original caoutchouc, groups of a typewhich may provisionally be represented as >C = 0, = C< in contrastto the type >c-c<0 3\/ , which is that suggested by Harries.The state in which caoutchouc exists in the latex of the plantswhich furnish it has been the subject of some dispute. Weberconsidered that the fluid contained a hydrocarbon, C2UH32, fromwhich caoutchouc was formed by a process of polymerisation duringthe technical preparation of the finished article, whilst de Jong,Tromp de Hass, and Harries held the view that the caoutchouc ispresent as such in the first instance. A recent determination 3 of themolecular weight, by an indirect process, of the caoutchouc obtainedby extracting centrifugalised Kickxia milk with benzene, led tothe estimated value 3173, which tells seriously against Weber’s 4 viewas the experimental errors would probably lead to a low ratherthan a high value.The same authors have carried out investigations on the natureof the process of vulcanisation of rubber, and infer that the productF.W. Hinrichsen and E. Kindscher, Bm., 1909, 42, 4329 ; A . , ii, 62.2 S. S. Pickles, Trans., 1910, 97, 1085.4 Zeitsch. Chenz. Ind. Kolloide, 1910, 6, 202 ; d., i. 330120 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.obtained by using sulphur chloride probably contains a definiteCOmpOUnd, (CloH&S2C12, and consists of a solution of this sub-stance in caoutchouc with varying quantities of absorbed sulphur.Attention should be drawn to a useful summary of the numerousresearches on cyclic hydrocarbons of the terpene series which confaintwo double linkings, including those known as terpinenes, whichhave given rise to so much discussion.6 All these products appearinvariably ta be mixtures of isomerides, and the terpinenes propercontain both A1 :3- and A1:4-dihydrocymene, as the oxidation productstestify.According t o Wallach, the former, or a-terpinene, isidentical with Semmler’s carvenene, and t’he latter, or 8-terpinene,corresponds with Semmler’s isocarvenene ; but neither of these hasbeen obtained in a pure state.a-8untalol.-Semmler’a researches on the sesquiterpene alcoholspresent in santalol, the oil obtained by distilling sandalwood oilwith stmeam, have been in progress for nearly ten years, and havereached an important stage,6 inasmuch as certain definite suggestionscan be made as to the exact constitution of one constituent.Theinvestigation of other terpenes, with only ten carbon atoms in themolecule, has been notoriously difficult, and it is therefore easy tounderstand that the study of the structure of similarly constitutedsubstances with molecules containing fifteen carbon atoms calls forextraordinary patience and experimental skill. Santalol contains a tleast two alcohols, a- and P-santalols ; both are probably representedby the molecular formula C,,H2d0, but their complete separationhas not yet been effected. Experiments on the various fractionsobtained indicated clearly that one of these, a-santalol, is a tricyclic,primary alcohol with an unsaturated linking, and the other,P-santalol, is a bicyclic, primary alcohol, with two double carbonlinkings.The fractions of lower boiling point, namely, those richestin a-santalol, yield much tricyclic eksantalic acid, CI2Hl8O2, andthe tricyclic aldehyde eksantalol (11), C12H180, with permanganateand ozone respectively. From eksantalol enolacetate by oxidation,in the manner indicated in last year’s report, noreksantalic acid(111) is produced; the aldehyde corresponding with this againyields an enoZacetate, which is converted into teresantalic acid. Thelatter is a saturated dicyclic monocarboxy_lic acid, and, accordingto Semmler, may certainly be represented by the formula (IV); ifso, there can be little doubt that a-santalol has the constitution (I) :0.Wallach, riwndea, 1910, 374, 217; A., i, 569.F. W. Semniler, Ber., 1910, 43, 1722, 1893; F. W. Semmlcr and B. Zaar,ibid., 1890 ; A., i, 573ORGANIC CHEMISTRY. 121CH, CH CH, CHI CH2 I\SH c’ Me-’ ---CH ?MeCH,OH \b/ CEC CH‘ I ’ \ CH ,’(111.)I CH2 ICMe-;----CH ‘,I,/ CHThe prdblem of t h s relationship between certain rare terpeneshas been solved during the course of experiments, which finallyled to the complete synthesis of sylvestrene. The ethylester of d-l-methyl-Al-cyclohexene-3-carboxylic acid (I), obtained byresolution of the inactive acid, was treated with magnesium methyliodide ; the resulting dihydrocarvestrenol (11), which was opticallyinactive, or nearly so, was converted by hydrochloric acid into thepure dihydrochloride of d-carvestrene. This dihydrochloride had[a]= + 22*0°, and was identical with sylvestrene dihydrochloride.As the latter compound yields sylvestrene (111) when it is acted onby aniline, the experiments establish the identity of sylvestrene withd-carvestrene, and unite in a remarkably concise manner the con-stitutional and synthetic data which were required to complete thischapter in the history of the terpenes :All the six possible menthenols of the meta-series and terpineolThese compounds are type have now been prepared synthetically.represented by the structures :7 W.H. Perkin, jnn., Proc., 1910, 26, 97122 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.HO*CMe, HOGMe, HO*CMe2H,\)Me H),,)flMe(1.1 (111.)IH IH2/\H H/\H,H2 H2 H2The list has been completed during the year 1910 by the additionof (V) and (VI); the starting point for both was l-methylcyclo-hexane-5-ol-3-carboxylic acid (VII), obtained by the reduction of5-hydroxy-m-toluic acid, from which, by displacement of the hydroxylgroup by bromine and removal of the elements of water, the isomericacids (VIII) and (IX) were obtained and separated:C0,H C02H C0,HIH IH I€€HI/\H2 4€, H / b ,HI1 IHMe 31 \\ )HMe \/ HOl IHMeH H2\/132(VIII. ) (IX.1 (VII.)The constitutions of the unsaturated acid were established byidentifying the product which they yielded on oxidation, after whichtheir esters were converted into (V) and (VI) respectively by meansof magnesium methyl iodide.The terpenes obtained by dehydrating the menthenols wereexamined, and possibly represent the corresponding isopropenyl-cyclohexenes; it has not yet been found possible to prove that theisomeric isopropylidene compounds or terpinolenes are not alsoformed at the same time.*cycZoGeraniolene, a mixture of two isomeric 1 : 1 : 3-trimethyl-cyclohexenes (XI) and (XII), obtained originally from citral, hasbeen prepared synthetically from 1 : 1-dimethylcyclohexan-3-one (X),which is itself a, reduction product from synthetic dimethyldihydro-resorcinol.9 The steps are indicated by the following scheme :W.H. Perkin, jnn., Trans., 1910, 97, 2129.A.W. Crossley and C. Gilling, ibid., 2215ORGANIC CHEMISTRY. 123CMe, CMe, CRIP,/\ /’\ /\\/ \/ \/CH2 CJ32 CH2CH, CH, -+ I -+ CH, CH, CH, 4H2 -+ I bH, A0 (3% c<;: CH, d<ge(X. 1CMe, C Me,CH, CH,b H , &Me CH, UMeCH CH2(XI.) (XII.)Among other new syntheses of terpenes may be recorded a simpleCHMe CMe CHMeCH, CH CH, CHHO*bH LH, 6E3 dE€, CH CH/\ /\\/ \/CH, CHand I IIone from thymoquinol 10/\\//\\//\\/CH, CH*OHIC C CHCHMe, CHMe, CHMe,(1.1 (11.) (111.)On reduction by Sabatier and Senderens’ method (compare thisreport, p. loo), the quinol was converted into menthane-2 : 5-diol,which, on dehydration, gave a terpene, for which the alternativeformulze (11) or (111) are suggested.Careful comparisons of the properties of certain synthetic terpinesand their derivatives from two sources, with those of naturalterpineol and limonene derivatives, have been made with the viewof eliminating all possible sources of error in the physical constantsof these important compounds.11.Polyazo-compounds.Carbon compounds which contain pairs of nitrogen atoms directlyunited with one another, including diazo- and hydrazo-compounds,hydrazones, and triazens, are now so generally familiar that theirdivision into distinct classes for discussion is probably advantageous,although simple relationships between these and certain ring com-pounds, such a.~ pyrazoles, may thus conceivably be lost sight of.Those classes of carbon compounds which contain groups of threelo G .G . Henderson and Miss M. M. J. Sutherland, Trans., 1910, 97, 1616.l1 W, H. Perkin, jun., and 0, Wallach, ibid,, 1427124 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.or more nitrogen atoms directly linked to one another as com-ponents of a ring, exhibit certain characteristics and undergotransformations which appear to justify their treatment in a singlesection.The most familiar type is doubtless that which includes substancescontaining the triazo-group, N,, the residue of diazoimide, and thestudy of these compounds, initiated by Curtius, has been greatlyextended within the last few years, as their great reactivity and theinteresting changes which they undergo doubtless accounts for thelarge amount of attention they have received.Attempts to prepare triazomalonic ester have so far led to negativeresults, and the observations made meanwhile indicate that thisester decomposes at the moment of its formation.On the otherhand, the triazo-group in monealkyl and aryl-malonic esters,Alk*CN,(CO,Et),, is remarkably stable, and even resists the actionof alkalis, which merely furnish the corresponding substitutedtriazomalonic acids. Similarly, a-triazomethylacetoacetic esters,Me*CO*CMeN3*C02Et, may be obtained without extraordinarydifficulty, and undergo the normal acetoacetic ester changes withalkalis and acids,, yielding triazopropionic acid and triazomethylethyl ketone (or, rather, its normal decomposition product, diacetyl).The observations are explicable in the light of experiments onH a-triazo-acids, of which only those containing the grouping >C<undergo the decomposition characteristic of a-triazo-ketones, with lossof twethirds of their nitrogen content. Similarly, the free alkyl-triazomalonic acids appear to be attacked by alkalis only in so faras they show some tendency to furnish triazoacetic acids by loss ofcarbon dioxide ; further, the aa-bistriazo-derivatives of malonic esterand acetoacetic ester have been isolated, and are found to bemoderately stable towards alkalis.12Among the novel and interesting triazo-compounds may be men-tioned triazoethylene, CH,:CH*N,, a pale mobile liquid, which hasbeen prepared by removing the elements of halogen halide fromtriazoethyl bromide or iodide, and triazoethyl ether,N,*CH,-CH,* O*CzH5,which is formed when triazoethyl alcohol reacts with ethyl iodideand silver oxide.13It is now a matter of common knowledge to organic chemists thatthe triazo-group exhibits a very decided tendency to react withunsaturated atomic groupings and to take part in the formation ofnew heterocyclic ring systems, such as those of the triazole and12 M.0. Forster and R. Miiller, Trans., 1910, 97, 126 ; M. 0. Forster and S. H.Newman, ibid., 1360.13 M. 0. Forster and S. H. Newman, ibid., 2570.NORGANIC CHEMISTRY. 125tetrazole series, this effect being brought about in some cases byinternal rearrangement, as with certain unsaturated substances con-taining the triazo-group, and in other instances by union of differentmolecular species.During the year some interesting examples havebeen chronicled.Methylcarbylamine and anhydrous azoimide unite in etherealsolution, giving rise to a substance, C2H4N4, which is considered byits discoverer to be a transformation product of triazomethylene-methylimine (I), and in view of the previous observation ofForster l4 and Schroeter,l5 is probably a derivative of tetrazole (11) :N:CH IN*NMeN,H + CNMe ---+ N,*CH:NMe -+ N<(1.1 (11.)Like tetrazole, i t is stable towards boiling water, but is decomposedby alkali, yielding carbon dioxide, methylamine, ammonia, andnibrogen.16With fulminic acid (I), azoimide yields a compound whichpresents all the characters of l-hydroxytetrazole (111), and probablyarises from triazoformoxime (11) ; its reactions correspond closelywith those of Forster's l-hydroxy-5-phenyltetrazole (Zoc.cit.) l7 :C:NOH + N,H -+(1.) (11.1 (111.)Acetylenedicarboxyljc acid unites with hydrazoic acid in etherealsolution, yielding 1 : 2 : 3-triazoledicarboxylic acid, and otherap-acetylenic acids behave in a similar way.18 Even acetylene reactswith hydrazoic acid in acetone at looo, and the product is 1 : 2 : S-tri-azole (I) itself. Phenylazoimide yields l-phenyl-1 : 2 : 3-triazole.Tetrazole (11) is the product when hydrogen cyanide and hydrazoicacid are heated together in alcoholic solution 19 :(1.1 (11.1The condensation of phenylazoimide with benzylidenephenyl-l4 Trans., 1909, 95, 184.l5 G . Schroeter, Ber., 1909, 42, 3356 ; A., 1909, i, 779 ; compare also Thiele,Annalen, 1892, 270, 1 ; A., 1892, 1298 ; and Hantzsch and Vagt, Annalen, 1901,314, 339 ; A., 1901, i, 194.E. Oliveri-Mandaltt, Atti R.Accad. Lincei, 1910, [v], 19, i, 228 ; A., i, 343.l7 F. C. Palnzzo, ihid., 218 ; A . , i, 342.l8 E. Oliveri-Mandala, and A. Coppola, ibid., 563 ; A,, i, 593.lQ 0. Dimroth and G. Fester, Ber., 1910, 43, 2219 ; A . , i, 645126 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,hydrazone to form 1 : 4-diphenyltetrazole, observed in 1907, is nowfound to take place in the following manner 20:The conversion of the acylazoimides into carbimides :R*CO*N, = R*NCO + N,,was discovered independently by Schroeter, Forster, and Stoermer.Schroeter was the first to publish any account of such trans-formations,21 and the statement to a different effect in last year'sreport 22 was therefore inaccurate.An interesting reaction, notunattended with danger to the operator, is one in which this t.rans-formation plays a part, namely, that which occurs when triazoacetylchloride is allowed to act on sodium azide. The expected triazo-acetylazide, N,-CH2*CO*N3, is not observed, but, instead, triazo-methylcarbimide is formed :This compound very readily loses the triazo-group as hydrazoic acidwhen in contact with cold solutions of alkali carbonates or withwarm water, a property which is in marked contrast with thecharacter of triazoacetic acid, and is considered to be consequent onthe presence of nitrogen directly attached to the carbon atom onwhich the triazo-group is situated.The carbimide is readily converted into a compound which isalmost certainly trist riazomet h y 1 isocyanurate, (N,= CH2*NC O),, sinceit is resolved by weak alkali into cyanuric acid, hydrazoic acid, andformaldehyde :(N,*CH,*NCO)3 + 3H20 = 3N,H+ (HNCO), + 3CH2:O.Derivatives of the carbimide, such as those obtained by the actionof ammonia and water, furnish formaldehyde by alkaline hydrolysis,the replacement of ON, by *OH doubtless leading to the formation ofderivatives of f ormaldehyde-ammonia at the intermediate stage :N,*C'H,*NHX + HO*CH,*NHX -+ CH,:O + NH,X.23N,*CH,*CO*N, =N,*CH,*N:C:O + N2.The analogy which subsists between derivatives of 1 : 2 : 3-triazoleand diazoamino-compounds was referred to in a former report.24 Inboth series is present the grouping *NR*N:N-, and the trans-formations which the 5-aminotriazoles undergo suggest that thethree-membered nitrogen chain may be resolved in the same manneras that in diazoamino-compounds, furnishing an amino-residue anda" 0.Djmroth and S. Merzbncher, Ber., 1910, 43, 2899 ; A., i, 897.21 Chew,. Zeit., 1908, 32, 933.z2 Ann. Report, 1909, 71 ; rompare M. 0. Forster and R. Muller, Trans., 1910,23 M. 0. Forster and R. Miiller, Trans., 1910, 97, 1056.24 A m . Aeport, 1909, 72.97, 1057ORGAKIC CHEMISTRY. 127a diazo-residue. These considerations have led t o a revision offormer views as to the nature of the isomeric changes which occurwhen certain substituted 5-hydroxy-1 : 2 : 3-triazoles (I) are fused ordissolved in organic solvents.It was formerly supposed that therelation between the isomerides was dependent on keto-enolicisomerism, and the alternative structure (11) for the neutralisomerides had been rejected because it represented them asderivatives of diazo-anhydrides, a supposition which appeared to be(1.) (11.)inconsistent with their remarkable stability.On the other hand, a complex similar to (11) was assumed byPiloty and Neresheimer to be present in ethyl diazomalonate, becausethis substance is not prone to decomposition, but the necessity forsuch a conclusion disappears when the properties of diazomethanoand diazoacetic acid are contrasted, for a great fall in reactivityconsequent on the displacement of a hydrogen atom by a carbethoxy-group is then revealed.Ethyl diazomalonate, by the action of coldaqueous ammonia, is converted into ethyl diazomalonamate (111),and the latter, in presence of sodium ethoxide, undergoes conversioninto ethyl 5-hydroxy-1 : 2 : 3-triazole-4-carboxylate, which on fusionregenerates ethyl diazomalonamate.NsOEtt- A1fiisiori - .-- .(111.) (IV.1These facts are not in harmony with the views of Piloty andNeresheimer, and a formula corresponding with (111) must beadopted for diazomalonic ester.The constitution of the neutral isomerides (VI) of the 5-hydroxy-triazoles follows readily if this conclusion be accepted. The formerare yellow, whilst the hydroxytriazoles are colourless. The sub-stance having the formula (VII) (formerly supposed to be methyll-phenyl-5-triazolone-4-carboxylate) can be converted by alcoholichydrogen sulphide into a hydrazi-compound (VIII), similar in allimportant characters to et-hyl hydrazimalonate, and yieldinghydrazine with hydrochloric acid :N NHPh* CO-C (CO,Me)<N N NHR*CO*CR<fJ(VI.1 (VII.)NHPh-CO*C( CO,Me)<kH NH(VIII.128 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.It thus appears that the hydroxy-triazoles in question and diazo-amides are usually mutually intraconvertible, as indicated by thescheme :The formation of the diazo-compounds from the triazoles is notto be observed in all cases; for example, 5-hydroxytriazole itself isstable; the reverse change, however, which is brought about byalkalis, seems to be general and complete.25Diazo-compounds.-Whilst the question of the constitution of thearoma-tic diazo-compounds has received little attention during thepast year, several interesting investigations have dealt with thisclass.The isolation of azomethane in 1909 26 renewed the hope ofobtaining diazo-compounds, similar to those of the aromatic series,but containing purely aliphatic radicles. The compound obtainedby Thiele in 1892, and then supposed t o be diazoguanidine nitrate,was shown by Hantzsch 27 to be carbaminoiminoazoimide nitrate,NH:C(NH,)*N,,HNO,. By diazotising aminoguanidine dinitrateat Oo in neutral solution, however, aminoguanidine diazohydroxide,C,H,N,,*OH,28 which behaves like an aromatic diazohydroxide,forming salts which couple with aromatic amines, and losing nitrogenwhen boiled with water, is obtained.The amphoteric character ofthe hydroxide, which forms crystalline salts with metals as well aswith acids, proves that it is not a diazonium compound, and itsreactions indicate that it contains either the anti-diazohydroxidegroup, *NH*N:N*OH, or the nitrosoamine group, *NH*NH*N0.2gThe two carbon atoms are connected by the tetrazen group, thus:It has been proved that the tetrazob ring is absent.The product obtained by the action of nitrous acid on amino-guanidine dinitrate in acetic acid is it diazoamino-derivative of ''Y ">C*N:N*NH*C<N*rH and has strongly acidN:N N:N t etrazole,properties.The tendency of recent work on these and other diazotisablecompounds is to show that a close analogy exists in this respectbetween aromatic compounds and open-chain compounds in which25 0.Dimroth, Annalen, 1910, 373, 336 ; A . , i, 518.26 Ann. Report, 1909, 95.zI A. Hantzsch and A. Vagt, Annalen, 1901, 314, 339 ; A . , 1901, i, 194.28 K. A. Hofmann and R. Roth, Ber., 1910, 43, 682 ; A . , i, 232.29 K. A. Hofmann, H. Hock, and R. Roth, ibid., 1087 ; A . , i, 446.30 K. A. Hofmann and H. Hock, ibid., 1866 ; A., i, 547ORGANIC CHEMISTRY. 129there is a certain distribution of groups possessing residual affinity,and the possibility still remains that true diazonium compoundsmay be obtained in t.he aliphatic series, given a suitable distributionof unsaturated linkings.Amino-derivatives of triazole are known to be diazotisable, andthe stability of the resulting compound is particularly great in thecase of the carboxylic acid, the product resembling diazobenzoicacid, although containing the elements of an additional moleculeof water.The sparing solubility and great stability are evidentlydue to the influence of the heavy carboxyl group, as it is found31that phenyl confers similar properties, phenyltriazole diazohydroxide,E---NH\ /C*N,*OH,C Ph*N being comparatively stable. In this case, aswith the corresponding derivatives of guanidine and thiazole, it isuncertain whether the compound should be regarded as an anti-diazohydroxide or as a nitrosoamine. A stable primary nitrosoaminemay be prepared by the action of nitrous acid on 6-nitro-4-amino-resorcinol, when a derivative of o-benzoquinoneoxime,NbHis obtained.32 The anti-diazghydroxide constitution in this case isexcluded by the absence of any reaction with acetyl chloride, andby the failure to couple with alkaline j3-naphthol when a solutionof the nitrosoamine in alcoholic hydrogen chloride is used, althoughthe normal diazonium salt, obtained by the action of fuming hydra-chloric acid, couples readily.The remarkable stability conferred on aromatic diazonium saltsby the introduction of heavy radicles has been previously noticed.33It is now found 34 that the naphthalene derivatives, which containa labile hydrogen atom t7hat might possibly migrate, giving riset o a quinonoid compound, retain their remarkable properties,including their deep colour, when this hydrogen is replaced byethyl, as in N2X*C,oHG*NEt*CO*CGH,.The same observation hadbeen made previously in the benzidine series, and the proof is nowcomplete for a series of p-benzoylaminoaryl- or pbenzoylalkylamino-aryl-diazonium salts, all of which exhibit considerable stability,whilst the colour increases with the complexity of the aryl group,the benzene series being colourless, the diphenyl series coloured to a31 W. Manchot, Ber., 1910, 43, 1312 ; A . , i, 442.32 G. Heller and A. Sourlis, ibid., 2581 ; A., i, 749.aa Ann. Report, 1907, 120.34 G. T. Morgan aid E. G. Couzens, Trws., 1910, 97, 1691.REP.-VOL. VII. 130 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.varying extent, and the naphthalene series uniformly colaured.Theevidence is decisive against the assumption of different structures forcoloured and colourless diazonium salts.Another stable diazonium salt has been observed in benzeneazo-benzenediazonium chloride, the absorption spectrum of which greatlyresembles that of benzeneazophenyltrimethylammonium iodide,36and a quinonoid diazonium formula is suggested :A further instance of the elimination of a nitregroup duringdiazotJsation has been observed in 2 : 3: 5- and 2 : 3 : 6-trinitro-p-anisidines, the 3-nitro-group of which is eliminated, yielding aquinonediazide 36 :OMe..ry2The measurement of the development of heat during the diazo-tisation of amines and the coupling of the resulting compounds withphenols has been employed s7 as a means of studying these reactions.One of the conclusions arrived a t is that the conversion of adiazonium hydroxide, ...into a diazohydroxide, R*N:N*OH,is accompanied by little o r no heat change.The conversion of a diazonium salt into a diazohydroxide is;probably the intermediate stage in the formation of diazoimides, a.reaction that has been studied in the case of sulphonyl derivatives.33”I n the following scheme, R may represent either an alkyl, aromatic,.hydro-aromatic, or mixed alkyl-aromatic radicle, and z itjs valencgr :R-N.013N )The reversible change probably takes place in several stages. I npresence of sodium acetate, the diazonium chloride is converted intoan acetate, which then undergoes hydrolysis to a greater or lessextent, and the resulting diazohydroxide then undergoes internal35 J.T. Hewitt and F. R. Thole, Trans., 1910, 97, 511.313 It. Melclola and F. Reverdin, ibid., 1204.37 W. Sventoslavsky, Rer., 1910, 43, 1479, 1488, 1767 ; A, ii, 555,3s G. T. Morgan and J. A. Pickard, Tran.?., 1910, 97, 48ORGANIC CHEMISTRY. 131condensation. When the radicle R is a heavy one,. the insolublediazoimide is precipitated, but the simplest members of the class,such as CH3*S0,*k*C,H4*N2, remain dissolved in a hydrated form,and are only isolated by evaporation. These pdiazoimides arealways coloured substances, whilst their ortheanalogues are colour-less, and the proper formulation of the compounds of this class thusbecomes of interest.Two formulze, (I) and (11), have been suggestedfor the cyclic diazoimines and diazoimides by Griess and Kekul6respectively :N(I. 1 (11.1C,€I,<~>NR C , J 3 4 < 3 Nwhere R is a hydrogen atom or an alkyl, aryl, or acyl group. Adecision between the two formulze is made possible by the intr+duction of a substituent into the benzene ring in order to renderthe molecule less ~ymrnetrical.~~ Representing the substituent by X,two isomerides are possible if Kekulg’s formula is correct, namely,C,H,X<P;K, N2 and -C,H,X<TR, whilst only one product would beN2obtained if the structure were represented by Griess’s formula.Instead of introducing a substituent, o-naphthylene compolinds maybe used in place of their o-phenylene analogues.The experimentalresults are in accordance with the first of these alternatives, twoisomerides being obtained in each case when the compounds studiedwere the o-naphthylenediamines and their benzenesulphonyl deriv-atives. All these ortho-compounds are colourless, and are nothydrolysed by concentrated acids, whilst their para- and peri-isomerides are yellow, and are decomposed by acids. As the formercompounds contain a five-membered triazole ring, and the latter aseven- and six-membered triazole ring respectively, the d o u r andinstability of the compounds containing the larger number of atomsin the ring is attributed to the strain thereby introduced.Constitution of isoNitroamhes.--isoNitroamines (substitutednitrosohydroxylamines) form two types of esters, for which the con-stitutions (I) and (11) have been suggested:The former, on decomposition, readily yield nitrous acid, whilstthe latter are stable or else give off nitrous oxide.a@ G .T. Morgan arid W. Godden, Trans., 1910, 97, 1702.K 132 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Similarly, the nitroamines give two series of esters supposed to berepresentable by the formulz (111) and (IV):N02*N R R’(111.)and these substances decompose in much the same way as do (I)and (11) respectively. Therefore those esters which are not truenitro- or nitroso-compounds lose the whole of the nitrogen of theircharacteristic complex, whilst the isomeric ones do not.I n the case of the pure isonitroamines, decomposition occurs as arule in accordance with only one of these modes, and hence it maybe surmised that they correspond in some cases with the type (I),in other cases with type (11).Menthoneisonit,roamine (V), however, can be decomposed in bothways; for example, when heated, it yields both pulegone (VII) and/3-nitromenthone (VI) (the latter being formed from nitroso-menthone by a secondary process of oxidation).On the other hand,in presence of alkali, only pulegone and nitrous oxide are obtained.40A similar behaviour is exhibited by a-pinenenitrohydroxylamine-oxime.41Trimens.-The first representative of the class of simple mono-substituted triazens, phenyltriazen, C,H,*N:N-NH,, was prepaTedin 1907,42 and was then found to exist in two isomeric forms. Theproducts obtained on reducing substituted phenylazoimides are evenless stable than phenyltriazen itself in many instances, but thep-bromo-, p-benzoyl, and p-carbethoxy-derivatives are somewhatmore stable,43 and the first is capable of undergoing an isomericrearrangement, which the instability of all such derivatives towardsreagents does not allow to be further investigated. Benzylazoimideyields only benzylamine and nitrogen on reduction, and so far analiphatic mono-substituted triazen has not been prepared.Onreducing hydrazoic acid with a copper-zinc couple at a sufficiently4u G. Cusmano, Gazzctta, 1909, 39, ii, 453 ; A . , i, 182.41 G. Ciismano, Atti R. Accad. Lincci, 1910, [v], 19, i, 747 ; A., i, 574.42 0. Dimroth, Ber., 1907, 40, 2376 ; A ., 1907, i, 653.0. Dimrotli and I<. Pfister, ibid., 1910, 413, 2757 ; A,, i, 904ORGANIC CHEMISTRY. 133low temperature, a solution is obtained which appears to containtriazen, NH :N*NH,, although decomposition proceeds very rapidly.Further lowering of the temperature merely prevents reduct,ion,and we are therefore still without knowledge of the parent substanceof the triazen series.Mixed aliphatic aromatic triazens, like their purely aromaticanalogues, exhibit dynamic isomerism, and the study of compoundsof this series, in which the aliphatic group is of high molecularweight, has marked advantages when it is desired to investigate thecourse followed by the react,ion. Methylaniinocamphor reacts withdiazonium salts, and the resulting camphorylphenylmethyltriazenmust have the constitution C,H14< !, since acidsresolve its salts into methylaminocamphor and the originaldiazonium salt.44 Camphorylphenyltriazen, on the other hand, isCH*N Me*N : N*C,H,?,LOunstable towards acids, nitrogencoupled with the reaction withcamp hordiazodip henylcarbamide,constitution (I) rather than (11) :CH*N:N*NH*C,H,(1.1C,T-IlS co ’I n previous investigations ofbeing liberated.This behaviour,phenylcarbimide, which formssuggests that the triazen has theCH.NH*N:N*C,K5C8H,4<~0(11.1the aliphatic-aromatic triazens,*5whilst-the action of acids has followed the course indicated byformula, (I), the molecule being resolved into the arylamine,nitrogen, and alkyl chloride by hydrogen chloride, the action ofphenylcarbimide has been t o convert them into a carbamide, fromwhich acids liberate the aryldiazonium salt.Forster and Garlandconsider, however, that the formula (I) is to be preferred for allsuch mixed triazens, and that the anomalous behaviour with phenyl-carbimide is to be attributed to the isomerisation of the resultingcarbamide. Whilst this isomeric transformation generally proceedstoo rapidly for any intermediate compound to have been a3 yetdetected, the weighting of the molecule by the heavy camphorresidue retards it considerably, and the first product (111) is readilyisolated, being transformed quantitatively into (IV) when thesolution in pyridine is heated or exposed to light:and although such a reaction involves the migration of so heavya group as C,H,*NH*CO*, it affords the most satisfact>ory explanation44 X.0. Forster and C. S. Garland, Trans., 1909, 95, 2051.45 0. Dimroth, Be?.., 1905, 38, 670 ; A,, 1905, i, 311134 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of the facts. The authors review the evidence, mainly due toDimroth, for the alternative formula for the triazens, and concludethat it is not in opposition to their conclusions. The formation ofthe mixed triazens from an aryldiazonium salt and an aliphaticprimary amine has then to be attributed t o the attraction exertedby the aryl group on the hydrogen atom being sufficient to bringabout the change:Alk*NH*N:N*Ar -+ Alk*N:N*NH*Ar.The principle is extended to the aromatic triazens containing twodifferent aryl groups, and the transformation recorded above, takenin conjunction with existing evidence, renders suspect conclusionsas to structure derived from a study of the action of phenyl-carbimide, once a favourite reagent for the purpose, and employedvery largely by Goldschmidt and others in work on the triazens.The question of the constitution of triazens containing twodifferent aromatic radicles has also been approached in anothermanner.In the very extensive series of investigations by Meldolaand Streatfeild in 1886-1895, it was demonstrated that threeisomeric alkylated diazoaminecompounds could be obtained. Thus,whilst diazotised mcnitroaniline and pnitroethylaniline yield thecompound (I), diazotised p-nitroaniline and m-nitroethylaniline yieldthe compound (11), the third isomeride, obtained by the directethylation of mp'-dinitrodiazoaminobenzene, being regarded as acompound of (I) and (11):/-\NEt N: N/-\BO,.(11.)\--/ \-/ \-/ \-/NO2/'-\N:N*NEt/-'NO,(1.)NO2It is now that the absorption spectra of (I) and (11),although similar, present quantitative differences, whilst (111) has aspectrum intermediate in character between those of (I) and (11),and identical with that of the non-ethylated triazen.The melting-point curve of mixtures of (I) and (11) is a continuous one with a,minimum, indicating that the isomeride (111) is an equilibriummixture of (I) and (11), and n0t.a compound. Unfortunately, themelting points were determined instead of the freezing points, andthe resulting curve therefore does not indicate whether the minimumis due to it solid solution or to a eutectic mixture of the two com-ponents, but the conclusion, that the product (111) is an equilibriummixture of (I) and (11), is now well established for the caseinvestigated.If the non-ethylated triazens are also regarded asequilibrium mixtures, then the formation of only a single productby the action of, for instance, phenylcarbimide, must be attributed.16 C. Smith and Miss C. H. Watts, TTazs., 1910, 97, 562ORGANIC CHEMISTRY. 135t o a selective attack of the reagent, equilibrium being continuallyrestored by the conversion of the one isomeride into the other.When, however, the aryl groups differ widely in character, insteadof being very similar, as in the case examined, it is possible thatthe triazen may consist entirely of one or other of the possibleisomerides, this having been shown to occur in the parallel instanceof the amidines, A ~ N : C P ~ O N H A ~ ' .~ ~ The physico-chemicalmethods referred to above are likely to afford useful informationin cases of this kind.A lkaloids.Steady progress has been made in determining the structure ofseveral of the more complex alkaloids, but investigations in thisgroup involve so many experimental stages, and the structures arein general so elaborate, that space does not permit of more thana bare summary of the results obtained. First in general intereststands a systematic review of the evidence for the constitution ofthe important alkaloids, strychnine and b r ~ c i n e .~ ~ The mode ofunion of the quinoline and carbazole nuclei in the strychninemolecule is discussed, andCH2 CH the annexed formula is/')\/\CH/\CH arrived at as representing\G,\/CH\/CH\/CH~\ the chemical properties of 7~ Q H ~ strychnine most completely. Y F ! co N-- CH CH, Brucine differs from strych-nine only in the presence ofmethoxy-groupe as substitu-CH2 '*OH ents in positions 1 and 4.The poisonous properties of the two alkaloids .are to be attributedto the ring containing the two nitrogen atoms (I), as a-piperidone(11) is found to have very similar properties:I I ' I\ / \\,// \ /(11.)-The presence of a double linking in one of the rings is also shownby the formation of a dibrpmide49 and of a peroxide containing47 H.v. Pechmann, Ber., 1895, 28, 869 ; A., 1895, i, 347.4* W. H. Perkiii, jun., and R. Robinson, Trans., 1910, 97, 305.49 R. Ciusa and G. Scagliarini, Atti R. Aecad. Lincei, 1910, [v], 19, i, 565; A . ,i, 583136 ANNUAL REPORTS ON THE PROGRESS OF CHIEMIS’I’RY.two atoms of active oxygen.50 Other reactions which have beenstudied 51 are also consistent with the above interpretation.The configurations of the cinchona alkaloids have been discussedafresh, in view of the fact that quinine, quinidine, cinchonine, andcinchonidine all yield the same a-oximino-PI-vinylquinuclidine (I)when the ketones obtained from them by oxidation react with amylnitrite, showing that all these alkaloids have the same spacialconfiguration with regard to the asymmetric atoms (1) and (2),whilst the properties of the deoxy-bases prove that the isomerism ofquinine and quinidine, and also of cinchonine and cinchonidine,depends on the mirror-image arrangement of the substituentsaround the carbon atom (3) 52 :0--CH,CH /‘,b IA revision of the reactions of berberine53 shows that themethoxy-groups have hitherto been wrongly placed, and theformula (11) is proposed.The fact thati a-phenyldihydroberberineyields small quantities of 2-benzoyl-3 : 4-dimethoxybenzoic acid onoxidation with permanganate is held 54 t o support Perkin’sformula (11).Since tetrahydroberberine contains an asymmetric carbon atom,the addition of an alkyl iodide should produce two isomeric iodides,and this is found to be the case.55A method for the preparation of 1-substituted isoquinoline basesconsists in the condensation of acylated carbinols of the formOH-CHPh*CH,=NH*CO*R (in which R = Me, Ph, or benzyl) withphosphoric acid and xylene, and this may be found useful in thesynthesis of alkaloids belonging to this group.5650 G.Mossler, Monatsh., 1910, 31, 329 ; A., i, 584.51 H. Leuchs and P. Boll, Ber., 1910, 43, 2362 ; H. Leuchs and P. Reich, ibid.,52 P. Rabe, Annabn, 1910, 373, 85; A,, i, 417.53 Perkin and Robinson, loc. cit.54 F. Faltis, Nonatsh., 1910, 31, 557 ; A., i, 698.65 A. Voss and J. Gadamer, Arch. Pharm., 1910, 248, 43 ; A., i, 415.56 A, Pictet and A. Gams, Ber., 1910, 43, 2384 ; A . , i, 773.2417 ; A., i, 766, 767ORGANIC CHEMISTRY.137The name (( pavine” is proposed57 for the compound formerlydescribed by Goldschmiedt as tetrahydropapaverine and by Pymanas 1 : 2-dihydropapaverine, the constitntion of which is still some-what doubtful. The relationship of pavine to laudanosine isrepresented by the following scheme :Papaverine methosulphate -??+ Laudanosine\ +I32 xN- Meth ylpavine.The alkaloid cryptopine, which commonly accompanies papaverine,is found to be a, saturated base, and t o contain two methoxy-groupsand one methyl attached to nitrogen. There is no phenolic,alcoholic, or ketonic oxygen.58In the morphine series, the production of pyrene when thebaineis distilled with zinc dust, affirmed in 1897 but denied by laterworkers, is now confirmed.59 Other work on this group relates tothe ethylthiocodides and ethylthiomorphides.60 The constitutions(I) and (11) are assigned to morphothebaine and thebenine, on theground of the formation of 1 : 3 : 5 : 6-tetramethoxyphenanthrenefrom the’ former, and oflatter 61 :H, NMe3 : 4 : 8-trimethoxyphenanthrene from theThe synthesis of narcotine is now completed by the synthesis ofcotarnine from myristicin, a tabular statement of the steps involvedbeing given.62 Gnoscopine is found to be the racemic form ofnarcotine. It is not present in poppy-juice, but is formed byracemisation during e ~ t r a c t i o n .~ ~Other work relates to picrotin and picrotoxin, some of the57 F. L. Pyman and W. C. Reynolds, Tmns., 1910, 97, 1320.5* A. Pictet and G.H. Kramers, Ber., 1910, 43, 1329 ; A., i, 502.59 M. Freund, ibid., 2128 ; A., i, 631.60 R. Pschorr and A. Rollett, Annalen, 1910, 373, 1 ; R. Pschorr, $bid., 15, 45 ;61 B. Pschorr, ibid., 51 ; R. Pschorr and F. Zeidler, ibid., 75 ; A., i, 423, 425.6L A. H. Salway, Trans., 1910, 97, 1209.63 P. Rabe and A. McMillan, Ber., 1910, 43, 800 ; A., i, 335.A., i, 419, 421, 423138 ANNUAL REPORTS ON THE PROGICESS O F CHEXISTRY.reactions of which have been studied,64 and to carpaine, to whichthe formula:Me H\/ His provisionally assigned, the nature of the group C,H,, beingunknown.65The synthesis has also been effected of two compounds, which areof importance on account of their occurrence as degradationproducts of alkaloids.These are m-hemipinic (I) and asaronic (11)acids :OMe/\CO,H OMe/\CO,H OMe/\NeOMeI lOMe OH1 1(111.)\/ 0MJ,,b02H \/(1.) (11.1The former is obtained from creosol (111) by methylation,nitration, reduction, and conversion into the nitrile, followed byhydrolysis and oxidation with alkaline permanganate. Asaronicacid is prepared by oxidising the dimethoxy-o-toluidine with ferricchloride, methyl being eliminated and methoxytoluquinone beingformed. This is reduced to the quinol, methylated, and oxidisedwith permanganate.66A number of papers dealing with adrenaline, the alkaloids ofergot, and compounds related to them have appeared. It is shown 67that ergotoxine contains a carboxyl group, and that ergotinine isits lactone or lactam.A small quantity of isobutyrylformamide,CHM%*@O*CO*NH,, is formed in the destructive distillation ofboth compounds.p-Hydroxyphenylethylamine may be synthesised in a simplemanner by condensing anisaldehyde with nitromethane to &nitro-p-methoxystyrene, reducing to p-methoxyphenylethylamine, andboiling with hydriodic acid.68 When methyl replaces one of thehydrogen atoms of the aminegroup, the physiological activity ofP. Horrmann, Ber., 1910, 43, 1903 ; F. Angelico, Atti R. Accad. Liiwei, 1910,[v], 19, i, 473; A., i, 577.G5 G. Barger, Trans., 1910, 97, 466.6R 13. D. W. Luff, W. H. Perkin, jun., and R. Robinson, i h X . , 1131.G7 G. Bargrr and A. J. Ewins, ibid., 284.6a K. W. Rocenmund, Ber,, 1909, 42, 4778 ; A , , i, 67ORGANlC CHEMISTHP.139this base is very slightly reduced, but the ethyl derivative is muchless active.69 In similar manner, the compoundwhich differs from adrenaline only in the absence of the hydroxylgroup from the side-chain, comes nearest to adrenaline in activity,but the ethyl derivative has only one-third, and the prop91 derivativeone-twentieth, of its ac tivit y.70 3 : 4-Di h ydroxy-8-p henylethyl-amine, although so similar to adrenaline, is much less active, and3-methyl-4-hydroxy-P-phenylethylamine is also much less active.71When methylamine reacts with chloro- or bromo-hydrins of thetype CC,H,(OMe),*CH(OH)~CH2Cl, compounds of both the adrenalineand isoadrenaline series, C,H,(OMe),-CH(OH)*CH2*NHMe andC,H,(OMe),*CH(NHMe)*CH,*OH, are obtained.72Naturally Occurring Substances.The Acids of Bile.-The action of hydrochloric acid on ox gallyields, besides glycine and taurine, three specific acids, cholic,deoxycholic, and cholleic acids, these last two being isomerides(Mylius, Langheld), and not identical, as was supposed byLatschinoff.The three specific acids are all largely converted by nitric acidinto choloidanic acid, C18H2808, and the mother liquors in each casecontain a pentabasic acid, Cl9Hz8Olo (“ Letsche’s acid ”).Thus thethree bile-acids are similarly constituted as to the grouping ofnineteen carbon atoms.The first oxidation products oE cholic acid are bilianic andisobilianic acids, C24HM08, tribasic diketonic acids which resistsomewhat energetic oxidation by potassium permanganate, andmust theref ore contain three totally hydrogenised carbon-ringsystems.Cilianic acid (Lassar-Cohn) is formed when bilianic acid is boiledwith alkaline permanganate; according t o Pregl, it has the formulaC2,H2,08, and is a tricarboxylic acid, the two oxygen atomsunaccounted for being probably present in carbonyl groups, althoughthe substance does not respond t o the usual tests for ketones; fromits formula and extremely stable character it may be concluded (1)that it contains two fully hydrogenised carbon-ring systems, a andb ; (2) that these must be united by a straight chain of *CH,*groups, and (3) that the nuclei have no side groups other than69 G.S. Walpole, Trans., 1910, 97, 941.F. L. Pyman, ibid., 264.G. Barger and A.J. Ewins, ibid., 2253.C. Mannich, Arch. Phurm., 1910, 248, 127; A,, i, 411140 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.carboxyls. As cilianic acid is obtained from bilianic acid, whichcontains three rings,. by the loss of four carbon atoms only, thepresence of a six-carbon ring in this acid may be inferred, twocarbon atoms being common to the rings b and c.Cholic acid contains a double linking, for it yields an ozonide,and its ring system must be the same as that in cilianic acid, andthe double linking must be present in ring (c). On oxidation withsulphuric acid in presence of mercury, it gives a considerablequantity of benzenepentacarboxylic acid (Schroetter), evidentlyaxising from destruction of the naphthalene-like system ( b c ) ; theremaining nucleus (a) (termed " Panzer's ring ") is almost certainlya hexahydrobenzene ring, and gives rise to the simpler benzene andhexahydrobenzene derivatives obtained from cholic acid byPanzer, whose results suggest the configuration CO2H<.in the neighbourhood of this nucleus,active dibasic pyrocholoidanic acid, C15H2004, orC0,H *C,H,*C,H,,*C02H,which contains a benzene nucleus, but gives a totally inactiveproduct when heated with enough potassium permanganate tosupply five atomic proportions of oxygen, a proportion correspondingwith the oxidation of to *CO,H, CO, and H,O.Thus C0,Hit may be inferred that the carbon atoms in this grouping formeda part of the original nucleus ( b ) , for the latter is united to anunbranched chain, which consequently must be *rCH2I5*.Thisrenders it necessary to represent nucleus ( b ) as a hexamethylenering, since it presumably contains no side groups other thancarboxyls. If the probable accuracy of this reasoning be admitted,then the formula of cholic acid may provisionally be representedby one or other of the two formuke:*2 H,/-\ H>C*Hrh, 'When choloidanic acid is heated, it is converted into optically*CH<cH3oORGANIC CHEMISTRY. 141The position of the substituents is as yet uncertain 73; the corre-sponding formulae for choloidanic acid and pyrocholoidanic acid arerespectively :H" H,CH(C0,H) *CH,.\-/332 I f 2CO,H-/' '1 [CH J5* C H<"3 CO, K\/-\/,CO,H andThe latter, when heated with soda-lime, should yield n-heptyl-benzene, and it is of interest to observe that a hydrocarbon obtainedby Pregl from " cholecamphoric acid " by such treatment agrees inproperties with that hydrocarbon.The isomerism of deoxycholicacid and choleic acid is also dealt with, but space does not permitfurther discussion of this interesting communication,EtkoZides.-This curious group of natural acids present in certainconifem 7* are known to represent systems of condensed hydroxy-acids, into which they are resolved when submitted to hydrolysis.Among the hydrolytic products, " juniperic " and " sabinic " acidsfrequent.ly occur, and these have now been identified as o-hydroxy-lauric acid (I) and o-hydroxypalmitic acid (11) respectively.The former may be reduced to lauric acid, and oxidised todecamethylenedicarboxylic acid (11) ; the latter, when reduced,yields palmi'tic acid, and is converted by oxidising agents into tetra-decamethylenedicarboxylic acid (111) :(I.) HO*CH,*[CH,],,*CO,H -+ CO,H*[CH,],,*CO,H (111.)(TI.) HO*CH2*[CH,],,*C0,H -+ CO,H*[CH,],,*CO,K (IV.).75Cork-An inquiry into the nature of cork has led the investigatort o the conclusion that the material is composed of an insolublemixture of the anhydrides and polymerides of solid and liquidaliphatic acids, together with their glycerides; the young cork isprobably composed of glycerides only, these being graduallyhydrolysed, and the acids thus formed either undergo polymerisationor are converted into anhydrides; in support of this view, thefollowing data are cited.A mixture of glycerides and cerin canbe extracted from cork by means of indifferent solvents, such aschloroform ; the insoluble residue submitted to the action of alcoholicpotassium hydroxide gives 30 per cent. of acids, but the glyceridescannot be detected. The crude acids are reconverted at 140° intoa brown, elastic, transparent mass, which is insoluble in indifferentsolvents and impervious to gases, and if sawdust is added in the73 Pregl, Zeitsch. physiol. Chem., 1910, 65, 157 ; A . , i, 321.74 Compare Ann. Report, 1909, 87.76 J. Bougault, Compt. rend., 1910, 150, S f 4 ; A., i, 297142 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,first instance, the product differs from cork in physical charactersonly in the absence of the microscopic structure peculiar to thenatural substance.The main constituent to which the acid mixtureowes its peculiar properties is suberic acid, which itself undergoessuch a change without loss of water when heated, being apparentlyconverted into a polymeride.76Chlorophyll and Haematin.Allusion was made in last year’s report to the appearance ofseveral important papers dealing with the constitution of chloro-phyll and hzmoglobin, and further memoirs on this subject haveappeared during the past year, although the progress made hasbeen perhaps less rapid than was anticipated. The close chemicalrelat-ionship which is now known to exist between these two colour-ing matters, so characteristic of the higher forms of vegetable andanimal life respectively, has obviously great biological importance,in addition to its interest from the point of view of the structuralchemist.Ilaemoglobin is actually a highly complex substance, containing avery heavy protein molecule, associated with a chromatogenic group,and it is the latter, freed from its accompanying protein, thatpresents itself as the analogue of chlorophyll.The presence oflecithin, long supposed t o be a component of the chlorophyllmolecule, has been disproved. Both colouring matters are metallicderivatives, chlorophyll containing magnesium, whilst haematin,from oxyhzmoglobin, is a ferric compound, the metal in eachinstance being held in a complex form. The relationship betweenthe two substances was remarked as far back as 1879 by Hoppe-Seyler, who found that the spectra of phylloporphyrin andhzematoporphyrin, coloured substances obtained as degradationproducts of the two pigments, and not containing a metal, resembledone another very closely.A t a later date, it was shown 77 that thesetwo compounds differ only in their oxygen-content. The furtherreduction of either phylloporphyrin or haematoporphyrin yields avolatile substance, hemopyrrole, C8Hl3N, the constitution of whichhas been much disputed. It is now 78 shown to be a dimethylethyl-pyrrole, eitherNH<CMe:yMe or NH<CH=CMeCH= CEt CMe:bEt’The constitution is proved by the action of nitrous acid. Whilst2 : 4-dimethylpyrrole yields the oxime of citraconimide, the 2-methyl76 M.von Schmidt, illonntsh., 1910, 31, 347 ; A., i, 560.7’ M. Nencki and J. Zaleski, Ber., 1901, 34, 997 ; A., 1901, i, 434.79 0, Piloty and E. Quitmsnn, ibid., 1909, 42, 4693 ; A,, i, 133ORGANJC CHEMIS’IXP. 143group being eliminated, hzmopyrrole, probably reacting in thesame manner, yields the oxime of methylethylmaleinimide. Thepresence of a propyl or butyl group, once generally assumed, is thusdisproved. The identity of the hzmopyrroles from chlorophyll andhaematin, and their analogy to dimethylpyrrole, has also beenshown by a comparison of the dyes which they yield with diazonium~alts.7~ The principal product obtained from hemopyrrole andbenzenediazonium chloride has the formula C8H,,N(N2Ph)2,HC1, buta second compound, N,Ph*C8H,,N-C8H,,N*N2Ph,HC1, is formed insmaller quantity.This was a t first believed to indicate the presenceof a dihemopyrrole in the original material, but it has since beenfound 8O that dimethylpyrrole, prepared synthetically, also yieldstwo analogous products.Haematin contains four pyrrole nuclei, of which two are probablyrepresented by hzmopyrrole, and two by hzemopyrrolecarboxylicacid, which is eitherAs haematin has the formula C3,H,,05N,Fe, it is evident thattwenty atoms of hydrogen must have been eliminated inthe condensation of these four groups to form the haematinmolecule. I n attempting to decide the manner in which this con-densation takes place, the relationship between blood-pigment andtryptophan, which is believed, on physiological grounds, to exist, hasbeen taken into consideration.The formula for tryptophan beingsuggests t,hat the side-chains of hzemopyrrole may be united toform a six-membered ring. One compound of this kind has beenprepared for the purpose of comparison, namely, a dimethylhydro-pyrrindole :by means of Knorr’s synthesis from aminoacebne and ethyIsuccinylosuccinate. The product tends to polymerise, and yieldsv9 Z. Leyko aiid L. Marchlewski, Riochem. Zeitsch., 1909, 22, 464 ; H. Malarskiand L. MsPchiewski, d i d . , 1910, 27, 246; A., i, 144, 692.80 L. Marchlewski and J . Robel, Bcr., 1910. 43, 260 ; A., i, 206144 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.dyes on oxidation, but it remains to be determined whether it bearsany immediate relation to blood-pigment.81The oxidation of hzmopyrrolecarboxylic acid yields hzmatic acid,which is probably the imide of Ar-pentenr -zy6-tricarboxylic acid 82 :Each molecule of hzematin yields two such molecules on oxidation.On the other hand, phylloporphyrin and other chlorophyllderivatives yield on oxidatmion one molecule of haematic acid andCO-gMetwo molecules of methylethylmaleinimide, N=<Co.CEt , pointingto a difference between a t least two of the pyrrole nuclei in hzmatinand the corresponding groups in chlorophyll.83Chlorophyll is a tricarboxylic acid, and the products obtainedfrom it by the regulated action of alkalis are di- and mono-carboxylic acids, still containing magnesium in a complex form.84Crystalline and amorphous chlorophyll differ only in the natureof the alcohols combined with the carboxyl groups, amorphouschlorophyll being, in part a t least, an ester of the simple unsaturatedalcohol phytol, C,,H,=OH, which is absent from the crystallinecompound.85The homogeneity of crystalline chlorophyll has not', however, beenallowed t o pass unquestioned.By the method of adsorptionanalysis,86 a separation into two fractions, differing in their absorp-tion spectra, is brought about,. The two spectra are identical withthose of two of the fractions formerly obtained from leaf-pigment,and now designated a- and P-metachlorophyllin respectively.87 Thedegree of dependence to be placed on the method of adsorptionanalysis is uncertain, but a possible chemical influence of theadsorbent used would appear to be excluded by the fact that theresults are not. affected by the substitution of inulin for calciumcarbonate.Another important question which has received much con-sideration is the manner in which the characteristic metal-magnesium in the case of chlorophyll, iron in that of hzematin-isunited with the remainder of the molecule.The chemical behaviourof these substances indicates that they are not salts of carboxylic0. Piloty, Ber., 1910, 43, 489 ; A., i, 277,8.j W. Kiister, Aia~zffileit, 1906, 345, 1 ; A., 1906, i, 337.85 R. Willstatter and Y. Asahina, i4id., 1910, 373, 227 ; A., i, 499.*4 R. Willstatter, Bcr., 1909, 42, 3955 ; A., 1909, i, 979.85 R. Willstatter and M. Benz, AnnnZen, 1907, 358, 267 ; A., 1908, i, 199.86 M.Tsvett, Ber. Dezct. bot. Gcs., 1906, 24, 354 ; A., 1907, ii, 144.8' M. Tsvett, Ber., 1910, 43, 3139 ; A . , 1911, i, 74ORGANIC CHEMISTRY. 145acids,88 but that the metal is present in a complex form, linked tothe iminic nitrogen of the pyrrole nuclei, the linking to carbon,assumed in the elaborate structaral formulz of Nencki and Zaleski(Zoc. cit.), being highly improbable. I n view of the studies ofWerner,, Ley, and Tschugaeff on the complex metallic derivativesof imides, biuret, and dicyanodiamidine, a formulation involvingthe use of subsidiary valencies has been proposed,89 the groupingin chlorophyll and hzemin (the hydrogen chloride compound ofhzematin) being respectively :C 11 1 o ro ph y 1 1. Kcelllill .The iron in hEmatin, etc., is in the ferric form, the presence offerrous iron, which has been observed in the products of fission,being due to the reducing action of the organic part of the moleculeon the ferric salt formed.HEmatin is to be regarded as containingthe group >Fe*OH, which passes into >Fe*C1 when this compoundis converted into hemin. The reduction of hematin by a varietyof reagents yields hzemochromogen, the chromatogenic constituentof the hemoglobin molecule,, from which Kuster concludes thatthe reduction is confined to the iron, and that hemoglobin is aferrous compound. I n that case oxyhEemoglobin must contain ahzmochromogen peroxide, whilst haematin corresponds, not withoxyhzmoglobin, but with methaemoglobin. This may be representedby the formulze:Hzmochromogen, Fe.0Haemochromogen peroxide, R:Fe< 1 0’Hzmatin, R: Fe OH.It must be admitted, however, that the relations of hzernoglobinand oxyhzemoglobin are not yet very satisfactorily expressed by suchf ormulze.Two minor points of interest arising out of recent work onhzematin call for a brief notice.91 The dimethyl ester of haemindissolves in pyridine, forming a complex in which pyridine is addeda t the FeCl group, recalling the behaviour of triphenylmethylbromide in pyridine.The compound obtained by the action ofThis was assumed t o he the case by 0. Piloty and S. Merzbacher, Ber., 1909,42, 3253, but was disproved by Willstatter, ibid., 3985; A., 1909, i, 857, 979.89 R. Willstatter and H. Fritzsche, Annalen, 1909.371, 33 ; A., i, 126.W. Kiister, Ber., 1910, 43, 370 ; Zeitsch. physiol. Chem., 1910, 66, 165 ; A.,W. Kiister, Ber., 1910, 43, 2960, 2962; A., 1911, i, 95, 69.i, 210, 529.REP.-VOL. VII. 146 ANNUAL REPORTS ON TITE PROGRESS OF CHEMISTRY.aniline on hzmin, and formerly described92 as ethyl anhydro-hzmaterate, proves to be merely dianilinoquinoneanil, formed bythe oxidising action of the hzmin on aniline, and is not thereforein any way related to blood-pigment.Proteins, Polypeptides, and Allied Compounds.The development of this branch of knowledge, although offundamental importance to biochemistry, has reached a stage whenadvances of general interest are comparatively rare. Every yearsees substantial progress both in results and in methods of attack,but the reporter, unless an expert in the subject, can hardly forma true estimate of the relative importance of the publications whichappear.The use of P-naphthalenesulphonyl chloride has been suggestedin determining the constitution of polypeptides 93; this substance iscoupled with the chloride in the usual manner, and the resultingsulphonyl derivative is hydrolysed by boiling hydrochloric acid.The P-naphthalenesulphonyl group remains in attachment to theterminal amino-acid residue, to that, on examination by Fischer’sesterification method of the products from the foregoing hydrolysis,the terminal residue may be identified.A complication ensueswhen tyrosinyl groups are present; in this case the latter, if presentas the terminal residue, appears among the hydrolytic products asdi-j3-naphthalenesulphonyltyrosine, otherwise the o-sulphonyl com-pound is .obtained.In this way it was shown that the terminalresidue in a silk peptone was alanine. Abderhalden’s94 work onthe products of partial hydrolysis of proteins is proceeding ; amongthe more recent results was the identification of dialanylglycine fromsilk.Until recently it was doubtful whether the proline residue existsi ~ s such in gelatin, as a-amino-bhydroxyvaleric acid may be con-verted into proline by the action of the hydrolytic agents previouslyused in hydrolysing the gelatin. Barium hydroxide does notcause such a transformation, yet when used t o hydrolyse gelatinan improved yield of proline is obtained, so that the latter isuvdoubtedly a primary product.95Synthetic work in this department is making continued progress.Stachydrine (a-prolinedimethylbetaine), CH~<CH2.NYe,*o ? ag2 W.Kiister and K. Fuchs, Ber., 1907, 40, 2021 ; A . , 1907, i, 572.93 E. Abderhalden and C. Funk, Zeitsch. physiol. Chem., 1910, 64, 436 ; A , ,yi E. Abderhalden, ibid., 1909, 63, 401 ; A,, i, 211.y5 E. Fisclier and It. Boehner, ibid., 1910, 65, 115 ; A . , i, 345.CH,*f: H-70i, 320ORGANIC CHEMISTRY. 14'7substame present in the root-nodules of Stachys tubifera and incertain other plants, has been prepared synthetically by convertingthe ester of hygric acid (1-methylpyrrolidine-2-carboxylic acid) intoits methiodide, and acting on this with silver oxide.96The constitution of arginine has been definitely established asa-amino-b-guanino-n-valeric acid,NH : C (NH,) *NH-[ CH2I3*CE( NH,) CO,H,by a synthetic method, which consisted in condensing the a-benzoylderivative of ornithine, NE2*[CH2],*CH(NH,)*C0,H, with cyan-amide, and hydrolysing the resulting a-benzoylamino-b-guanino-n-valeric acid.97The original literature should be consulted for other synthesesof important derivatives of pyrrolidine g* and ih carboxylicacid.99Condensation products of amino-acids with glycerol have beenprepared in order to examine their behaviour, especially towardshydrolytic agents.1 The results may assume significance in laterdevelopments of protein chemistry, and the same remark appliesto those obtained in an examinatioh of certain polypeptides whichare produced by condensing amino-acids with amino-aldehydesY2 andpossibly future reporters may have occasion to enlarge upon thesepoints.Certain acylated arnino-acids are readily converted into com-pounds which are now regarded as lactones derived from a group*CO*NH*, functionating in the enamic 3 form *C(OH):N-.Thusanthranoylanthranilic acid, with excess of acetic anhydride, doesnot yield a simple acetyl derivative, as previous workers hadsupposed, but the lactone,7Me:N0-co anthranil '' has the structure >C,W, and benzoyl-anthranilic acid is similarly constituted.A number of other acylated amino-acids, for instance, benzoyl-alanine, yield compounds of this type, which are intermediate inproperties between lactones and acid anhydrides.They combinereadily with ammonia, with scission of the lactone ring, and theproducts, when heated with alkalis, are converted into lactimes or96 E. Schulze and G . Trier, Ber., 1909, 42, 4654; A . , i, 62.97 S. P. L. Sorensen, ibid., 1910, 43, 643, A., i, 227.98 E. Fischer and A. Luniak, ibid., 1909, 42, 4752 ; A., i, 136.99 E. Fischer and G. ZemplQn, ibid., 4878 ; A., i, 100, etc.E. Abderhalden and M. Guggenheim, Zeitsch. physiol. Chem., 1910, 65, 53 ;A., i, 2262 C. D. Harries and I. Petcrsen, Ber., 1910. 43, 634 ; A . , i, 228.Compare Aim. &port, 1909, 100.L 148 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.cyclic imides, corresponding with the original lactones ; forexample :Dipeptides containing the residues of some of the higher fattyacids have recently been synthesised in view of their possiblephysiological importance.Thus, for example, a-aminclm-nonyl-glycine, NH,-CsH,,*CO-NH*CH,-CO,H, was formed by convertinga-bromononyl chloride into a-bromo-n-nonoylglycine, and acting onthe latter with ammonia.Similar compounds, containing the residues of alanine andleucine, as well as the corresponding lauryl com-pounds, wereisolated .5A tetrapeptide, glycylaspartyldiglycine,has been prepared synthetically,6 and a number of dipeptides ofserin,7 which have an interest in connexion with certain naturalproteins.The bacterial cleavage of histidine (I) under anzrobic conditionsleads in certain circumstances to the formation of carbon dioxideand fl-amino-4-ethylglyoxaline (11), thus proving that the amino-group is present in the a-position with respect to the carboxylgroup, a matter which heretofore has been somewhat uncertain :CH CH/\ /A TH 7 CH-C *C H,*CH,*NH, YH r C H=C *CH,*CH(NH,)*CO,H(1.) (11.1Enzymes.The authors of this report have carefully considered thedesirability of inserting chapters discussing the more importantresults obtained during the last few years in the study of enzymeaction, including fermentmation.The subject, although of theutmost importance and intimately associated with organicchemistry, demands for its proper exposition a special and intimateknowledge to which the present writers cannot lay any claim; forthis reason, also, their estimate of the relative importance of theE.Molir and F. Kohler, J. p r . Chem., 1909, [ii], 80, 521 ; E. Mohr andT. Geis, ibid., 81, 49 ; E. Mohr and F. Stroschein, ibid., 473 ; A., i, 116, 117, 483.A. Hopwood and C. Weizmann, Proc., 1910, 26, 69.E. Fischer and H. Roesner, zbid., 199 ; A., i, 657.I). Ackerniann, Zcitsch. physiol. Chcm., 1910, 65, 504 ; A., i, 419.ti E. Fischrrand A. Fiedler, Annalen, 1910, 375, 181 ; A . , i, 656ORGANIC CHEMISTRY. 149published contributions in this field is not likely to be an accurateone, and they therefore prefer to make no selection from the massof experimental data on record. I n connexion with fermentation,however, attention may be drawn t o a useful summary of recentviews on the mechanism of the process,g as well as t o an importantmathematical paper on the (( RGle of Diffusion in Fermentation byYeast Cells.” 10A short reference may be made to some controversial work onthe oxydases and peroxydases.The view was originally pro-pounded by Bertrand that these substances are complex organiccompounds of manganese, and it is stated11 that even after purifi-cation has been carried so far that all coagulable proteins havebeen removed, minute quantities of manganese always remain. Norelation, however, could be traced between the proportion ofmanganese and the activity of the oxydase, and other workersclaim that active preparations may be obtained free from eithermanganese or iron.12 Metallic salts accelerate the action, manganesesalts being particularly active in certain cases, and the function ofthe metal appears to be, like that of a peroxydase, the transferenceof oxygen from the peroxide initially formed to the oxidisablesubstance.On this view, the action of oxydases is a chemicalprocess, exactly comparable with the oxidation of indigotin by air inthe presence of benzaldehyde.13 The autoxidation of organic com-pounds containing amino- and hydroxy-groups in presence of ,copperhas been studied in some detail,l4 and it is found that metalliccopper is not only dissolved by ammonia in contact with air, butalso by solutions of amines, and of glycols, glycerol, or mannitol.The copper in such cases evidently forms complex compounds, whichact as carriers of oxygen. I n view of the fact that oxyhaemoglobin,which contains iron in a complex form, behaves like an organicperoxydase,l5 the nature of the part played by complexes containingmetals in reactions of this kind calls for a more thorough investi-gation.As bearing on this point, attention may be called t o experimentson the direct chemical action of organic peroxides on unsaturatedcompounds.Thus, benzoyl hydroperoxide, CGH5*CO*O*OH, oxidises9 Miss 0. E. Ashdown and J. T. Hewitt, Trans., 1910, 97, 1636.l9 A. Slator and H. J. S. Sand, ibid., 922.l1 A. W. van der Haar, Ber., 1910, 43, 1321, 1327 ; A., i, 604.12 A. Bach, ibid., 364, 366, Arch. Sci. phys. mi., 1910, [iv], 30, 152 ; A., i,13 See also R. A. Gortner, Trans., 1910, 97, 110 ; H. Euler and I. Bolin, 2eit.sch.14 W.Traube, Ber., 1910, 43, 763 ; A., i, 294.J5 J. Wolff and E. de Stoeklin, Compt. rend., 1910, 151, 483 ; A., i, 802,291, 801.yhysikal. Chern., 1909, 69, 18’7 ; A., i, 84150 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.olefines, geranioI, limonene, and a number of other substances t ooxides,16 and converts aniline into either azobenzene or nitroso-benzene, according to the proportions used, whilst acetyl or benzoylperoxide may be used for the oxidation of diphenylamine, acyl-diphenylhydroxylamine being formed at first, and then undergoingmolecular rearrangement, with the formation of several morecomplex derivatives.l7Organic Compounds of Sulphur.Certain phases in the study of these compounds are of generalinterest, and investigations include studies of compounds having abiochemical importance, while others throw light on problems ofisomeric change and, more generally, the influence of residualaffinities on physical and chemical properties.The latter aspect ofthe chemistry of sulphur is especially interesting when reviewed inconnexion with the influence of oxygen in modifying physical andchemicaI properties, and rapid developments may be anticipatedfrom a comparative study of the effects produced by these tworelated elements.A few instances of the influence of sulphur in modifying theproperties of compounds may be mentioned. The absorption oflight by sulphur compounds is much greater than that of thecorresponding oxygen compounds, and the following atomic groupsgive rise to definite absorption bands which are not given by theiroxygen 'analogues :s:c<z:, s:c<;:, s:c<;:, o:c<;-, *s*q:o *s*y:o- *S*C:O' *o.c:o'whilst the characteristic bands of phenol and benzyl alcohol areobliterated when the oxygen is replaced by sulphur, owing to theinfluence of the latter element on the distribution of residualaffinity in the ring.l*The influence of sulphur in rendering active an adjacentmethylene group is also very remarkable, the two methylene groupsin ethyl thiodiglycollate, S<CH,.CO,Et, being highly reactive,condensing readily with a-diketones, o-quinones, and similar com-pounds.The influence of the carbethoxy-group in producingCH,* C0,Et16 N. PrileschaBeff, Ber., 1909, 42, 4811 ; 1910, 43, 959 ; E.Lippmaiin, ibid.,l7 S. Gambarjan, ibid., 4003 ; A . , 1909, i, 910.464 ; A., i, 86, 149, 295.J. E. Purvis, H. 0. Jones, and H. S. Tasker, Trans., 1910, 97, 2287ORGANIC CHEMISTRY. 151activity is small, so that the effect must be attributed chiefly to thesulphur .19The sulphone group, SO,, influences an adjacent methylene groupin the same manner, so that the compounds R*SO,*C'H,*CN,R*S0,*CH,CO*NH2, and R*SO,=CH,*CO,Et show reactivity of akind similar to that exhibited by compounds in which CO take8the place of SO,, although the properties naturally vary greatly withthe nature of the group adjacent to the methylene group.Cheiroh-Remarkable results have been obtained during theexamination of the alkaloid-like compound present in wallflowerseeds,20 which was identified as a methylsulphone of propylthio-carbimide, such a structure being probably unique among naturallyoccurring substances ; its synthesis has been accomplished in thefollowing manner.Methyl y-phthaliminopropyl sulphide (I), obtained from sodiumrnethylmercaptide and y-bromopropylphthalimide, was convertedby hydrolysis into phthalic acid and methyl y-aminopropyl sulphide(11).The latter, in the form of its hydrochloride, was oxidised tothe corresponding sulphone (111), which w&s converted by carbondisulphide, in accordance with Hofmann's method, into cheirolin(IV) 21:C,H5<gE>N*C,H,.S*CH, NH,* CH, CH, CH,* S * CH,(1.) (11.1NH,*CH,*CH2*CH,*S02* CH, S: C:N* CH,* CH,*CH,*SO,* CII,(111.) (IV.)During the last decade, Autenrieth and his collaborators haveshown that certain dihydric mercaptans readily condense withaldehydes and ketones, forming compounds which contain six-, seven-,or sixteen-membered rings containing sulphur.The work hasrecently been extended t o the formation of rings from the para-and meta-xylylene dihydrosulphides. pXylylene hydrosulphidecondenses with aromatic aldehydes t o form compounds containingeighteen-membered heterocyclic rings ; with benzaldehyde and hydro-chloric acid it yields duplo-p-xylylenebenzylidenemercaptal :C,H4<CH2*S*CEIPh.S.cB, 6 4'CH,*S*CHPh*S* CH,>cSimilarly constituted substances, but with smaller rings, areWork has also been undertaken bearing on the relative stability2o Compare Wagner, Chem.Zeit., 1908, 32, 76 ; A., 1908, i, 202.formed when m-xylylene hydrosulphide is used.220. Hinsberg, Ber., 1910, 43, 901 ; A,, i, 334.W. Schneider, Aiznabn, 1910, 375, 207 ; A., i, 658.W. Autenrieth and F. Reuttel, Ber., 1909, 42, 4346, 4367, A., i, 60, 61152 ANNUAL REPOltTS ON THE PROGltESS OF CHEMIS'I'RY.of rings containing different numbers of carbon atoms united withthe sulphur atom, and the ring (I) is then found to be formedreadily, whilst (11) is only obtained with difficulty23:>SyH2* C H,CH,*CH,(1.1 (11.1Aromatic disulphides are decomposed at 240-280° into mixturesof monosulphides and trisulphides, and in certain cases nearly inthe proportions required by the equation :2S2Ph2 = SPh,+ S3Ph2.24The presence of substituting groups, such as carboxyl, in thearomatic nucleus does not materially alter the course of thereaction, although secondary products, such as thioanhydrides, maybe formed.Organic sulphides in which the sulphur is directly attached to amethyl or methylene group combine with a molecular proportion ofhalogen; if the two groups attached to sulphur are both aromaticin type, this reaction does not take place. Similarly, the derivedsulphoxides yield dibromides on treatment with hydrogen bromideonly if the sulphoxy-group is not in attachment to two aromaticnuclei.25The reactivity of mercaptan and also the oxidising power ofsulphur dioxide is shown in a striking manner when they a c t onone another in glacial acetic acid; in presence of hydrogen chloride,a mixture of benzyl disulphide and benzyl trisulphide is formed inquantitative amount, as represented by the equation :4C6H5*CH2*SH -1 so, = (c6H5*cH&s2 + (C6H5*CH2),S3 + 2H20.26Phosphorescent Sulphur Compounds.-Certain derivatives of thio-carboxylic acids are oxidised by air at the ordinary temperature,emitting fumes which are luminous in the dark. The effect appearst o be associated with the presence of the group S:C*O* in themolecule, and, in the series which exhibit it, is more pronouncedwith the volatile members. Dithiocarbonic esters, OR*CS*S,R', t h bcarbamic esters, NR,*CS*OR, as well as the esters CSCOMe), andMe*CS-OMe, and chlorides of the type Cl*CS*OMe, all behave in thismanner, but the isomeric compounds containing the group *S*C*O*are inert. It would thus appear that the grouping S:'C* has anexceptionally high residual affinit~.~'..23 J. von Braun and A. Triimpler, Ber., 1910, 43, 545 ; R., i, 274.24 0. Hinsberg, ibid., 1874 ; A., i, 553.25 E. Frornm and G. Raiziss, Awzalen, 1910, 374, 90 ; A., i, 554.26 J. A. Smythe and A. Forster, Trans., 1910, 97, 1195.27 M. Delepine, Cmnpt. rend, 1910, 150 876 ; Bztll. SOC. chim., 1910, [iv], 7,722, 724 ; A,, i, 295, 612, 613ORGANIC CHEMISTRY. 153The luminescence of thiocarbamic esters is found to be stimulatedby alkalis, and in open vessels proceeds to completion, neither ozonenor hydrogen peroxide being produced. It has been suggestedthat an unstable peroxide is first formed, which decomposes intocarbamate and sulphur monoxide, which reacts with the alkali,yielding thiosulphat,e ; salts of another acid, H,S,O,, intermediatebetween sulphurous and thiosulphuric acid, are also said to bef ormed.28Zsomeric Change in Sulphur De&vathes.-It has been found thatthe ortho-sulphoxides of diphenylamine (type I) are transformedby the action of acid reagents into the corresponding azothioniumderivatives (type 11) :HO CH,\/NII N N/\HO Ac f i C(1.) (11.1 (111.)The product which is obtained by the action of acids on N-methyl-diphenylamine o-sulphoxide is of similar character to that obtainedfrom the parent compound, and, since it yields N-methylthio-diphenylamine on reduction, and N-methylchlorothiodiphenylamineby the further action of halogen acid, it is clear that the N-alkylgroup of the sulphoxide has not suffered transposition during thechange. The substance is accordingly represented by the formula111. Assuming that. the reaction pursues the same course withthe imino-compounds as with the N-alkyl derivatives, it is evidentthat with the former the change does not proceed by directmigration of iminic hydrogen.29The mechanism of the reaction has been further discussed withdata obtained from the study of the relative speeds of change indifferent, sulphoxides with acids of varying strength, and it isconcluded that the reaction in question depends on the preliminaryformation of a salt of the sulphoxide, which by some furtherprocess is transformed into the sulphonium derivative. This con-clusion has been confirmed by the isolation of the hydrochlorideof trichlorodiphenylamine o-sulphoxide, which is very readily transformed into the azothionium derivative when gently warmed inBarnett and Smiles, Trans., 1909, 95, 1253 ; 1910, 97, 186 ; Brady and28 0. Billeter, Ber., 1910, 43, 1833 ; A . , i, 564.Smiles, ibid., 1910, 97, 1559154 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.certain media. It is clear that the conversion of the sulphoxidesalt (IV) into the azothionium derivative proceeds either byseparation of the elements of water or by migration of hydroxylHO HNH/\A/\I I I I\/A/\/S/\OH C1\/N/\/\/\I I I I\A/\/Sfrom quadrivalent sulphur to tervalent nitrogen. The latteralternative appears to be correct, as in all the cases studied theazothionium compounds contain an additional molecule of water,which seems to be present in an ammonium hydroxide complex (V),as is also the case with the N-methyl derivative (111).I n presence of excessso of hot halogen acids, these phenazo-thionium salts are capable of further intramolecular change, beingconverted into halogen derivatives of tliiodiphenylamine. Thus,with excess of hydrochloric acid, phenazothionium chloride yieldschlorothiodiphenylamine (VI), and a similar change takes placewith the N-methyl deritrative :N N H/\/\/\ A/\/\I I I I --3 I I I C 1 L\/\/\/ \A/\/61 (VI.)S SSince diphenylamine o-sulphoxide (I) is obtained by the actionof hydrogen peroxide on thiodiphenylamine, it would seem thatthe process of chlorination of the latter substance takes place inthree stages, namely, production of (1) sulphoxide, (2) sulphoniumchloride, and (3) the chlorclsubstitution derivative, each of whichmay be isolated.The additional knowledge of phenazothionium derivativesobtained in examining these intramolecular changes has beenapplied to the further study 31 of the S-phenylphenazothioniumPage and Smiles, Trans., 1910, 97, 1112.31 Barnett and Smiles, ibid., 362ORGANIC CHEMISTRY. 155group. The structure NPh(VII.)which was previously assigned 32 to the products obtained from thecondensation of aromatic substances with certain sulphoxides ofdiphenylamine, is now certain, and the analogy between thesesubstances and the parent phenazothionium group is demonstrated.This study of the phenazothionium group is brought t o a conclusionin a paper 33 dealing with the S-alkyl derivatives which are obtainedfrom thiodiphenylamine by the addition of alkpl iodide in presenceof mercuric iodide. Under these conditions the alkyl iodide uniteswith the bivalent sulphur group, and mercuri-iodides of thealkylated bases are obtained. These alkylated bases seem to bestable only in the form of the double salt, for on removing themetal by the usual means, the alkyl group is eliminated. However,silver hydroxide attacks the methyl derivative (VIII), yieldingvery small quantities of the quinonoid S-methylphenazothioniumbase.Selenophen, yH:CH>Se, may appropriately be mentioned in this CH:CHsection. It has been obtained by heating sodium succinate withphosphorus triselenide, and forms a yellow, mobile, irritant liquid.34It is not pretended that the foregoing selection of subjectsincludes all the most important advances of the year 1910, or thatthe investigations selected are of superior value t o those omitted.The necessity of choosing a few topics from the mass of publishedwork of the year involves the omission of much that is interestingand important, whilst a certain degree of arbitrariness unavoidablyattaches to the selection of topics for discussion. It is hoped,however, that the brief summaries of progress in certain depart-ments of organic chemistry may be of assistance in guiding thestudent, who can trace the more detailed development of anybranch by means of the annual index. The theories of organicchemistry are in a state of transition, and it may well be thatthe reporters of a few years hence may find the spstematisationof their material an easier task than at present, owing to the33 Ann. Eeport, 1908, 166.33 Barnett and Smiles, Tmns., 1910, 97, 980.34 Foa, Gazzctta, 1909, 39, ii, 527 ; A . , i, 187156 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.advance in knowledge of the relations between the structure andproperties of organic compounds. It is impossible to resist theconclusion that many of the partial explanations adopted at thepresent time are tentative, and are destined to be embraced inwider generalisations, which will have the effect of giving to thisbranch of chemistry a far greater degree of homogeneity andsymmetry than it now possesses.CECIL H. DESCH.ARTHUR LAPWORTH

ISSN:0365-6217    

DOI:10.1039/AR9100700057

出版商:RSC    

年代:1910

数据来源: RSC

摘要:

ANALYTICAL CHEMISTRY.ALTHOUGH, as the writer has previously observed, it is extremelydifficult to give a connected critical review of the progress thathas been achieved in this branch of chemistry during the year, heventures to think that, in the present report, it has been possibleto piece together several interesting observations into what may betermed historical paragraphs. The quality of the papers publishedin 1910 appears to have improved. Not only have an exceptionalnumber of new suggestions been made, but additional activityis being shown in the no less important direction of revisingexisting methods with the view of increasing their accuracy orof placing them on a sounder scientific basis. Despite this, areviewer cannot fail to discern that a leaning towards novelty, oftenat the expense of utility, is still in evidence. This is perhapsparticularly noticeable in researches emanating from physiologicallaboratories. When a method is required for a, certain purpose forwhich there may exist one, if not more, of known accuracy, thephysiologist, instead of making himself acquainted with these,devises a fresh one, which, as often as not, is unsound and untrust-worthy.It is a healthy sign, however, that limit of accuracy isreceiving increasing attention from most investigators, althoughthere are still numerous instances in which necessary pre-cautions are neglected, whilst in others ridiculous and unnecessaryrefinements are adopted. Further, it is still true that someof the problems that have been worked out can at best bedescribed as mere students’ exercises leading to no useful results.The Society of Public Analysts and other Analytical Chemists hasundoubtedly done much by its investigation scheme in indicatingproblems that await solution, and the number of researches carriedout under the terms of the scheme, although a.s yet small, quitejustifies its existence. Increasing utility may be anticipated toaccrue from it in the future.General.A decomposition flask for use in conjunction with the nitrometerhas been devised by E.Berl and A. W. Jurrisen.1 It is adaptedfor the estimation of nitrogen in smokeless powders, and may alsoZeitsch. angew. Chem., 1910, 23, 241 ; A . , ii, 240158 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.be used2 for the assay of calcium carbide, sodium amalgam, andzinc dust.E. Berl3 describes some ingenious absorption andextraction apparatus, and also two forms of weighing pipette-onea modification of that devised by Lunge and Rey for weighingliquids such as “ oleum,” and another for weighing liquids of highvapour tension. Apparatus for the estimation of sulphur trioxidein “ oleum ” has been devised by G. Finch 4 and by R. H. Vernon.5F. Emich and J. Donau6 describe an apparatus by means ofwhich small quantities of precipitates-a few milligrams-may becollected. The method may be applied quantitatively in conjunctionwith a Nernst micrebalance.A simple and efficient fractionating column has been devisedby A. Hahn.7 Its action depends on the presence of a coolingliquid, maintained at its boiling point by the vapours of the liquidbeing fractionated, which thus acts as a dephlegmator.Whilst itrequires no attention, it is shown that mixtures of ether and alcohol,methyl and ethyl alcohol, and methyl ethyl ketone and diacetylhave been successfully fractionated. I n attempting to fractionatea liquid under diminished pressure with the ordinary form ofdephlegmator, a considerable amount of liquid is often condensedin the column. To obviate this, L. Bouveault * has devised a still-head which is too wide for the formation of a long layer ofcondensed liquid.A desiccator, which can be exhausted and also heated, is describedby J. H1adik.QA. Eleine10 has devised an apparatus for the estimation ofsulphur and arsenic in iron and steel, whilst another apparatus forthe estimation of carbon sulphur and arsenic in iron and steel isdescribed by G.Preuss,ll and also an apparatus for the estimationof sulphur.12 For the estimation of arsenic by the Gutzeit method,an apparatus has been devised by H. Kasarnowski.l3P. A. Kober14 upholds the accuracy of the aeration method ofdistilling off ammonia from a solution.2 Zeitsch. angew. Chenz., 1910, 23, 248 ; A., ii, 242.3 Chem. Zeit., 1910, 34, 438 ; A., ii, 538.Zeitsch. ges. Schiess. und Xprznystoflwesen, 1910, 5, 167.Chem. Zeit., 1910, 34, 792 ; A., ii, 803.6 Monatsh., 1909, 30, 745 ; A., ii, 152.7 Ber., 1910, 43, 419 ; A., ii, 183.8 Bull. SOC. chim., 1910, [iv], 7 , 273 ; A., ii, 485.9 Biochem.Zeitsch., 1910, 28, 29; A., ii, 930.lo Chem. Zeit., 1910, 34, 636; A., ii, 749,11 Zeitsch. nngew. Chem., 1910, 23, 1980 ; A., ii, 1109.l2 Chem. Zeit., 1910, 341, 840 ; A., ii, 893.l3 Ibid., 299 ; A., ii, 451.l 3 J. Amer. Chem. SOC., 1910, 32, 689 ; A., ii, 661ANALYTICAL CHEMISTRY. 159The solvent properties of trichloroethylene ( I ‘ Westrosol ”) havebeen investigated by L. Gowing-Scopes.15 A non-inflammableliquid, boiling a t 8 8 O , it dissolves mercuric halides, nitrous acid,ammonia, hydrogen sulphide, chlorine, bromine, iodine, and sulphur,besides most organic compounds that do not contain two or morecarboxyl or hydroxyl groups. Although withstanding the action ofalkalis, it cannot, as an unsaturated compound, be used in presenceof oxidising agents.L. Gutmann16 describes an improved form of Kipp’s apparatus,which, without taking it t o pieces, enables the spent liquid to bedrawn off.An apparatus which gives a constant supply of eitherhydrogen sulphide or its saturated solution has been devised byS. Urbasch.17A modified Soxhlet extraction apparatus is described byJ. 35. Sanders18; it enables the solvent to be distilled off after theextraction is complete without disconnecting the apparatus. Itappears, however, to occupy much more room laterally than theordinary Soxhlet extractor.Physical Analysis.Among physical methods that have been called into use inanalyt.ica1 chemistry must be mentioned the proposal of W. Hempeland R. von Klemperer 19 to estimate potassium in presence ofsodium (1 : S), and calcium in presence of sodium (1 : 100) spectro-metrically.The method can also be applied to the estimation oflithium and of thallium. It is specially recommended for soilanalysis.P. Dutoit 20 shows that the point of complete precipitation maybe determined by electrical conductivity measurements. I f , forinstance, successive quantities of a concentrated solution of an iodideare added to a dilute solution of a, silver salt by means of it capillaryburette capable of being read to 0.001 c.c., and the conductivityafter each addition is plotted as a, function of the volume of pre-cipitant added, two approximately straight lines are obtained whichintersect at a, point corresponding with complete precipitation.The temperature must not vary within +Oslo.I n conjunctionwith P. Mojoiu,21 he has applied this method to the volumetricestimation and separation of the alkaline earth metals.l5 Analyst, 1910, 35, 238 ; A., ii, 647.l6 Zeitsch. angew. Chem., 1910, 23, 728; A., ii, 493.Chem. Zeit., 1910, 34, 1040 ; A., ii, 949.Proc., 1910, 26, 227.l9 Zeitsch. nngew. Chem., 1910, 23, 1756; A., ii, 995.2o J. Chim. phys., 1910, 8, 12 ; A., ii, 342,21 lbicl., 27 ; A., ii, 343160 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.For polarimetric purposes, the oxygenated salts of sodium arerecommended as giving very intense flames, for example, nitrates,nitrites, chlorates, etc. The flames are said to be sufficiently strongto enable the rotatory power of osazones to be determined.22Gas Analysis.A new principle has been suggested for the separation of gasesby E.Erdmann and H. Stoltzenberg,23 namely, that of fractionalcondensation by liquid air, liquid oxygen, solid ether, alcohol, andcarbon dioxide. It has been applied with results of the highestaccuracy to the analysis of the following gaseous mixtures : ethyleneand hydrogen, ethylene and oxygen, carbon dioxide and oxygen,nitrous oxide and oxygen. Probably it will be of service chieflyin supplementing the ordinary methods. Apparatus for this newmethod is described by H. Stoltzenberg.24 Equally novel is theproposal of C. Paal and W. Hartmann25 to absorb hydrogen ingaseous mixtures by a solution of colloidal palladium and picricacid.I n these circumstances, the picric acid is reduced by thehydrogen, the palladium acting as a catalyst. I f any of the con-stituents present in a mixture besides hydrogen are absorbable,they must be removed previously by ordinary reagents. The use ofa solution of phosphorus in castor oil, instead of the solid substance,for absorbing oxygen from gaseous mixtures has been suggestedby M. Centnerszwer.26 A refractometric method for the analysisof gaseous mixtures has been devised by L. Stuckert.27 By itsmeans, 0.01 per cent. of methane can be detected in air, but hereit must be observed that, as in all physical methods, the methodcan only be used with certainty when the constituents of a mixtureare known. The refractive indices of a number of gases are given,the determinations having been made by a Jamin interferometer.E.Hintz and L. Griinhut 2g deal with the estimation of methanein gases from natural springs, whilst F. Henrichz9 has improvedFresenius's method of estimating hydrocarbons in natural gases,and describes a new apparatus for the purpose.For technical gas analysis, A. H. Elliott has devised an apparatusfor the analysis of illuminating gq30 which, according to E. C.22 C. Neuberg, Bioclaem. Zeitsch., 1510, 24, 423; A . , ii, 446.23 Bcr., 1910, 43, 1702; A . , ii, 649.25 Ibid., 243 ; A., ii, 237.26 C'hem. Zcit., 1910, 3, 494 ; A., ii, 541.27 Zeitsch. Elektrochem., 1910, 16, 37 ; A . , ii, 245.Zeitsch. anal. Chem., 1910, 49, 25 ; A . , ii, 356.29 Zcitsch angew. Chem., 1910, 23, 441 ; A., ii, 355.30 J.Soc. Chem. Ind., 1910, 29, 1 9 2 ; A., ii, 353.Ibid., 1708 ; A., ii, 649ANALYTICAL CHEMISTRP. 161Uhlig3I gives results agreeing well with those obtained whenHempel's apparatus is used. Uhlig 32 describes an apparatus forthe analysis of oil gas. He has tested Elliott's photometric lamp,and finds it very codstant.33 G. N. Huntmley34 describes a usefulgas sampling tube, suitable for taking samples of flue gases.A. Gwiggner 35 describes a modified Hempel burette,36 and L. L. deKoninck 37 a modification of Nowicki's gas-absorption pipette.A form of the Toepler pump has been devised by B. D. Steele,s*by means of which the gas from the apparatus being exhaugted maybe collected. A simplified form of the Toepler pump is also describedby A.von Antropoff.89G. Calvi40 gives a description of a new apparatus for theestimation of carbon dioxide in air by Lunge and Zeckendorf'smethod.Indicators.Some important communications have been made during theyear on the ionic theory of indicators and on the measurement ofthe concentration of hydrogen and hydroxyl ions in a solutioncolorimetrically.41 E. Vassallo 42 ascribes the disappearance ofcolour on adding concentrated alkali to phenolphthalein to the re-formation of the lactone form. It has been shown that 2 : 5-dinitro-quinol is a compound giving a very wide range of colours withdifferent acids and bases, and it has been recommended for theestimation of the concentration of hydrogen and hydroxyl ions inunknown solutions.43 None of these papers permits of useful con-densation.A new indicator, said to be equal in sensitivenessto phenolphthalein, is 6-sulpho-~-naphthol-l-azo-m-hydroxybenzoicacid.44 a-Naphtholphthalein is said to be an indicator the sensitivepoint of which is very close to neutrality, the concentration ofhydrogen ions a t this point being between 10-7.2GAT and lO-8.68N.46J. SOC. Chem. Id., 1910, 29, 194 ; A , , ii, 354. 32 Ihid., 196 ; A., ii, 354.y3 Ibid., 197. 34 Ibid., 196 ; A . , ii, 354.35 Zeitsch. nngew. Chcnt., 1910, 23, 642 ; A., ii, 445.36 Compare also L. I,. de Koninck, &dZ. Soc. chim. Belg., 1910, 24, 231 ; A.,37 Ibid.,'233 ; A., ii, 648.38 Phil. Mug., 1910, [vi], 19, 863 ; d., ii, 602.39 Chem.Zeit., 1910, 34, 979 ; A, ii, 947.4o Giorn. Farm. CJhim., 1910, 59, 289.O1 See A. A. Noyes, J. Amer. Chem Soc., 1910, 32, 815 ; A., ii, 746 ; H. l'.42 Boll. Chim. Farm., 1910, 49, 345.43 I,. J. Henderson and A. Forbes, J. Amer. Chem. Soc., 1910, 32, 687 ; A., ii,44 R. Mellet, Chem. Zeit., 1910, 34, 1073; A,, ii, 995.46 S. P. L. Sorensen and S. Palitzsch, Biochem. Zcitseh., 1910, 24, 381 ; A., ii, 446,REP,-VOL. VII, Mii, 648.Tizard, Trans., 1910, 97, 2477.641162 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Inorganic Chemistry.$ditatiue.--The scheme of Abegg and Herz 46 for the detectionand separation of the more important negative ions has beenrevised and modified by T. Milobendski.*7 He claims to haverendered it much more precise.A delicate reagent for the detection of nitric acid is said to be asolution of di-9 (1 0)-hydroxyphenant hrylamine in concentratedsulphuric acid, which changes by oxidation from blue to wine red.Nitrous acid also gives the reaction, but much larger quantitiesare required, and when it occurs it is owing to the formation ofnitric acid. Hydrogen peroxide, chloric and chromic acids do notgive the reaction.48 Pyrogallol dimethyl ether is recommended asa very delicate test for chromic acid, ferric salts, and nitrites.Chloroform extracts the yellow colouring matter.49 It has beenstated that arsenic acid may be detected in presence of phosphoricacid by the white precipitate which results when a solution ofammonium molybdate and nitrate is added to that to be _testedwhich must cont'ain acetic acid.50Some useful observations have been made on the detection andseparation of the heavy metals that are not precipitated by hydrogensulphide in acid solution.Thus a scheme f o r their separation hasbeen devised,51 whilst it has been shown that on addition ofammonium perchlorate to ammoniacal solutions of cobalt, nickel,manganese, and cadmium salts, these metals are completely pre-cipitated as perchlorates of the metallic am mine^.^^ It has beenstated that potassium cobalticyanide gives, in presence of sulphurousacid, a red precipitate with zinc salts and a yellow precipitate(which turns green on heating) with nickel salts, both precipitatesbeing soluble in an excess of the reagent. The nickel precipitate isbleached by tartaric acid.53 The rose colour of a solution of cobaltnaphthenate in benzene has been suggested as a test for cobaltin presence of nickel, whilst it has been stated that paper colouredwith this solution is bleached when moistened with dilute hydrogenperoxide.54When sodium cobaltinitrite is added to a faintly acid solution of46 Zeitsch.anorg. Chesn., 1900, 23, 286; A . , 1900, ii, 436.47 J. RWX Phys. Chew,. Soc., 1909, 41, 1301 ; A., ii, 154.49 J. Meyerfeld, Chcnz. Zcit., 1910, 34, 948 ; A., ii, 901.6o G. Maderna, Atti R. Accnd. Lincei, 1910, [v], 19, ii, 68; A., ii, 896.61 J. Petersen, Zeitsch. anal. Chem., 1910, 67, 253 ; A., ii, 654.52 R. Salvndori, Cazzetta, 1910, 40, ii, 19 ; A . , ii, 1002.6s E. 1'. Alvarez, Amz.Chim. ma!., 1910, 15, 129; A., ii, 454.o4 K. W. Charitechkoff, Chenz. Zeit., 1910, 34, 50, 479; A., ii, 238, 549,J. Schmidtand H. Lumpp, Ber., 1910, 43, 432, 794 ; A . , i, 313, ii, 450ANALYTICAL CHEMISTRY. 168a thallium salt, a red, crystalline precipitate of the compositionTh,Co(N02), is formed. The reaction is said to be delicate, andwhen employed conversely serves for the detection of cobalt inpresence of nicke1.56A very sensitive reagent for copper is said to be a solution of1 : 2-diaminoanthraquinone-3-sulphonic acid in sodium hydroxide.A blue coloration is produced.56J. Piccard 57 having suggested that H. J. H. Fenton’s colourreaction with quadrivalent titanium and dihydroxymaleic acid maybe due to tervalent titanium, Fenton has since shown58 that thecolorations produced by quadrivalent and tervalent titanium aredistinct..0.F. Kirby 59 recommends asbestos threads soaked in phosphoricacid, dried, rolled together and ignited, for flame coloration tests,borax beads, etc.Quantitative.Non-Metals.-The suggestion has been made to estimate freehalogens by shaking solutions containing them with a known weightof electrolytically deposited silver in an atmosphere of hydrogen anddetermining the increase in weight,GO and it is obvious that themethod may be used for the indirect estimation of a large numberof substances.61 The method of estimating iodide in presence ofbromide or chloride-oxidation with permanganate, extraction ofthe iodine with carbon tetrachloride, and titration with t h i ssulphate-originally proposed by Sammet,62 has been shown to giveresults accurate to within 0.1 per cent.63For the estimation of small quantities of nitrates, say a fewcentigrams, it has been suggested to apply the Pelouze reaction-action of an acidified solution of ferrous chloride on a, nitrate-and for the measurement of the nitric oxide evolved in this reactionan apparatus of the Schultze-Tiemann type has been devised byA.T. Davenport.64Several papers have been published during the year dealing with55 S . TanatarandS. Petroff, J. Buss. Phys. Chm. SOC., 1910, 42, 94 ; A., ii, 350.6F R. Uhlenhuth, Chent. Zeit., 1910, 34, 887 ; A, ii, 898.b7 Ber., 1909, 42, 4341 ; A., i, 67.58 Ibid., 1910, 43, 267 ; A., ii, 244.69 Chem.News, 1910, 101, 170; A , , ii, 445.6o F. A. Gooch and C. C. Perkins, Amcr. J. ScL, 1909, [iv], 28, 33 ; A,, 1909,ii, 932 ; and C. C. Perkins, ibid., 1910, [iv], 29, 388 ; A , , ii, 542.61 Compare ibicl., 1910, [iv], 29, 640; A . , ii, 669.62 Zeittxh. physikal. Chem., 1905, 68, 684 ; A., 1906, ii, 153.6;1 W. C. Bray and G. M. Mackay, J, Amer. ChePJz. ,See., 1910, 32, 1198 j A.,ii,@ J. Amer. Ch?n. Soc., 1910, 32, 1237 ; B., ii, 898,896.nr164 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the estimation of phosphoric acid volumetrically, but since themethods proposed are in some cases more complicated andapparently less accurate than those now in use, they need not bediscussed. An interesting, lengthy, and important review onmagnesium ammonium phosphate, and the best conditions for itsprecipitation in analysis, is published by K.Bube.65The benzidine method of estimating sulphuric acid has now beenproved to be one of considerable utility by numerous observers,and some useful details of its application to the analysis of pyritesand to the estimation of sulphuric acid in presence of chromic saltsand chromic acid are given by G. von Knorre.66 It is well knownto chemists that the assay of fuming sulphuric acid (“oleurn ”) isattended with some difficulty, and the simple and rapid methoddevised by H. Howard,67 which is specially suitable for works’requirements, is therefore welcome. It depends on the measure-ment of the heat evolved when a known weight of the sample isdiluted with sulphuric acid of 92 per cent.concentration.The fact that arsenic may be distilled rapidly from its solutionsin one operation in presence of hydrochloric and hydrobromic acidsand a salt of hydrazine is a useful addition to our knowledge.68I n the estimation of small quantities of arsenic by the Marsh-Berzelius method, it was shown by Chapman and Law in 1906 thatthe addition of a salt of cadmium t o the generating flask (wherebymetallic cadmium is deposited on the zinc) increases the sensitive-ness of the zinc. W. D. HarkinsGg finds that the same effect isproduced by the salts of all metals of high excess potential, forexample, tin, lead, and bismuth.A method of estimating cyanides by titration with a nickel saltin neutral solution has been proposed.The end point is indicatedby a turbidity due to the precipitation of nickel cyanide. It givesfairly accurate results, and may be used in presence of halides andthiocyanates.70 It will be remembered that H. G. Colman 71 recom-mended the Feld method of estimating ferrocyanides. F. W.Skirrow 72 has brought forward experimental evidence that theresults are 3 to 4 per cent. too low. This has since been refutedby Colman,73 who shows that there is a loss of hydrogen cyanide,65 Zeitxh. anal. Chem., 1910, 49, 525 ; A . , ii, 804.66 Chem. Zeit., 1910, 34, 405 ; A., ii, 545.67 J. SOC. Chem. Ind., 1910, 29, 3 ; A , , ii, 239.68 Y. Jannasch and T. Seidel, Ber., 1910, 48, 1218; A , , ii, 546.G9 J. Amer. Chem. SOC., 1910, 32, 518; A., ii, 451.70 H.Grossmann and L. Holter, Chem. Zeit., 1910, 341, 182 ; A,, ii, 349.71 Analyst, 1908, 33, 261 ; Ann. &port, 1905, 201.n J. SOC. Chcm. Ind., 1910, 29, 319 ; A., ii, 361.73 Analpst, 1910, 35, 295 ; A,, ii, 761ANALYTICAL CHEMISTRY. 165although only of 0.6 per cent., if the boiling with magnesiumchloride be protracted ; not, however, if his conditions 74 be adheredto. The loss during the conversion of the ferrocyanide into mercuriccyanide is also shown t o be less than stated by Skirrow. J. L.Foucar 75 corroborates Colman’s statements.Metals.-Volumetric methods of estimating lead and zinc, depend-ing on titration with potassium cyanide, are described by E. Rupp,76whilst H. Grossmann and L. Holter 77 deal with the estimation ofzinc by titration with potassium cyanide in presence of ammoniumchloride, potassium iodide, and silver nitrate.A tintometricmethod for the approximate estimation of small quantities of leadhas been devised by A. G. Vernon Harcourt.78 The proposal toestimate mercury in presence of silver and of the two metals togetherby titration with thiocyanate appears worthy of attention,7g as doesalso the suggestion to estimate small quantities of silver bycoloration produced (colloidal silver) when a solution is heated withsodium hydroxide and a carbohydrate or glycerol.8OH. F. V. Little and E. Cahen81 show that Benkert and Smith’smethod of separating bismuth from lead, double precipitation asbismuth formate$2 gives good results.Last year, 0.Baudisch 83 showed that nitrosophenylhydroxyl-amine, known as “ cupferron,” precipitates iron and copperquantitatively, and he gave a number of instances of its use in theanalysis of ores. His results have been confirmed by H. Biltzand 0. Hodtke,s4 who give some further useful details. Silver,mercury, lead, and tin are said to be precipitated quantitatively by(‘ cupferron.” 85A method for the separation of antimony and tin was describedlast year by L. TN. McCay?G and further details are now publishedby the same author.87 According to W. Plato,@3 ant4imony and tinmay be separated by distillation. To a solution containing thetwo metals, sufficient concentrated sulphuric acid is added to raise74 L O G . cit.76 Chem. Zeit., 1910, 34, 121 ; A., ii, 243.77 Ibid., 181 ; A., ii, 349.78 Trans., 1910, 97, 841.79 E.Rupp and F. Lehmann, Chgm. Zeit., 1910, 34, 229 ; A . , ii, 350.80 G. S. Whitby, Zeit,Pch. anorg. Chcm., 1910, 67, 62 ; A., ii, 654.81 AnaZyst, 1910, 35, 301 ; A., ii, 755.8’2 J. Amer. Chem. Soc., 1896, 18, 1055 ; A., 1897, ii, 755.83 Chem. Zeit., 1509, 33, 1298 ; A,, ii, 76.tx Zeitsch. anory. Chcm., 1910, 66, 426 ; A., ii, 550.85 Compare J. H a n d and A. Soukup, ibid., 68, 52 ; A., ii, 899.86 Ann. Beport, 1909, 143.87 J. Amr. Chem. SOC., 1910, 32, 124 ; A., ii, 1003.88 Zeitsch. anorg. Chem., 1910, 68, 26 ; A,, ii, 903.75 Ibid., 300166 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,the boiling to 155--165O, and distillation commenced in a currentof carbon dioxide, when the antimony passes over.More sulphuricand hydrochloric acids are then added, together with bromine, andthe distillation continued in a current of sulphur dioxide, the tinpassing over as tetrachloride a t a temperature of 180-190O.H. Reckleben and A. GUttisch89 point out that the hydrides ofantimony and arsenic behave similarly towards silver nitrate solu-tion. They state that the deposited silver cannot be taken as ameasure of the antimony, as it is invariably contaminated withantimony oxide; further, that the complete oxidation of antimonyhydride to antimonic acid is only possible if a convenient solventbe present. Their observation is worthy of note that alkali andalkali earths decompose antimony hydride more readily than arsenich ydride.H.E. Palmer 9O has applied the principle of oxidation withpotassium ferricyanide in alkaline solution and titrat'ion of theresulting ferrocyanide with permanganate to the estimation ofarsenic, antimony, tin, vanadium, and chromium, and in this con-nexion attention may be called to two papers in which the titrationof ferrocyanide with permanganate is discussed.91Several papers dealing with the estimation of nickel and cobaltdemand notice. I n the first place, E. L. Rhead92 has submittedseveral methods for the estimation of nickel in nickel steel to a,critical investigation, and he concludes that the Brunck-Ivanickimethod (precipitation with dimethylglyoxime) is the most accurateand rapid, the separation of iron being effected by basic precipitation.H.Grossmann and B. Schuck, criticising Rhead,93 claim as greataccuracy for their dicyanodiamidine method.94 They point out,however, that titration with potassium cyanide is just as accurate,and far more r a ~ i d . ~ 5For the estimation of both nickel and cobalt, E. Rupp andF. Pfenning 96 describe a method of direct titration with potassiumcyanide. The assay liquid (neutral to methyl-orange) is run into ameasured volume of N/2-potassium cyanide solution. In the caseof nickel, the cyanide may be run into the assay liquid. The endpoints correspond with the ratios Co: 5KCN and N : 4KCN.97 Amethod for the estimation of nickel and cobalt, which is claimeds9 Zeitsch. anal, Chem., 1910, 49, 73 ; A , , ii, 352.90 Amer. J.Sci., 1910, [iv], 29, 399, 30, 141 ; A , , ii, 546, 902.91 W. Mecklenburg, Zeitsch. nnorg. Chem., 1910, 67, 322; A . , ii, 761 ;92 A.ii,aZysst, 1910, 35, 97 : A., ii, 353.93 lbid., 247 ; A., ii, 658.95 Compare Campbell and Arthur, ibid., 1908, 191.96 Chem. Zcil., 1910, 34, 322 ; A., ii, 458.97 Compare, however, H. arossmann, ibid., 673,E. Miiller and 0. Diefenthaler, ibdd., 418 ; A., ii, 910.O4 Ann. Report, 1907, 205ANALYTICAL CHEMISTRY. 167to be particularly adapted for the estimation of nickel in steel, hasbeen devised by G. S. Jamieson.98 It depends on titration withpotassium ferrocyanide, and from the results quoted it appears veryaccurate.The precipitation of iron, aluminium, and chromium as basicformates has been recommended on the ground that the precipitatesfilter better than the acetates.99 When titrating ferrous salts bypermanganate in presence of hydrochloric acid, it is shown thataccurate results can be obtained if phosphoric acid be, added.1When silicates are decomposed by sulphuric and hydrofluoric acids,the excess of the latter should preferably be converted into hydro-fluosilicic acid by addition of pure silica, and the ferrous irontitrated with permanganate.2Volhard's well-known permanganate method for the estimation ofmanganese has been studied by W.M. Fischer? who has suggestedthe addition of glacial acetic acid to the boiling liquid just beforethe titration is completed, which causes the precipitate to subside.E. Cahen and H. F. V. Littlezb show that the liquid should bebelow boiling point when the acetic acid is added.The experimentaldata which they bring forward goes t o prove that the accuracy ofthe method for the analysis of such substances as ferromanganeseand pyrolusite compares f avourably with that of gravimetric andvolumetric methods in general use. Two modifications of theVolhard-Wolff method of estimating manganese are described byE. Deiss.3 It has been found that a solution of manganese insulphuric acid is oxidised to the quadrivalent state by sodiumbismuthate, and a method for the estimation of manganese basedon this fact has been described by F. J. Metzger and R. F.McCrackan .4The difficulty of separating calcium and magnesium by the oxalatemethod when the magnesium largely predominates is well known,and E.Murmann 5 has suggested dissolving the mixed chlorides inalcohol and precipitating the calcium from this solution aasulphate.The method for the estimation of alkalis originally devised by98 J. Amer. Chem. SOC., 1910, 32, 757 ; A., ii, 658.g9 0. F. Tower, ibid., 953 ; A., ii, 900.G. J. Hough, ibid., 539 ; A., ii, 457.J. Fronime, Tsch. Min. Mitt., 1909, 28, 329; A., ii, 351.2a Zeitsch. aml. Chenz., 1909, 48, 751 ; A., ii, 76.Analyst, 1911, 36, 43.Chem. Zeit., 1910, S, 237; A., ii, 351 ; compare E. Donath, ibid., 437;J. Amer. Chent. Soe., 1910, 32, 1250 ; A., 'K, 1000.A., ii, 550.6 Zeitsch. anal. Chem., 1910, 49, 688 ; A., ii, 897168 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Lawrence Smith 6 has been studied by T.Doring? who gives somevaluable hints concerning it. H. Roemer 8 has published a usefulsummary of the methods for the analysis of potash salts (native)adopted by the International Congress of Applied Chemistry atBerlin, 1903. The accuracy of the cobaltinitrite method ofestimating potassium volumetrically originally devised by Adieand Wood, and further developed by D r ~ s h e l , ~ has been doubtedby certain observers; but a modification has now been devisedwhich, on the evidence of several chemists, gives results which aresometimes, although rarely, 1 per cent. too high.10 W. C. Ball11has developed his method of estimating sodium and w i u m assodium caesium bismuthinitrite,lZ and his results are highly satis-factory, None of the positive ions commonly associated withsodium, for example, calcium, magnesium, lithium, interferes.Ammonium chloride should not be present in concentration aboveN / 5 , and phosphate, if it occur in more than traces, must beremoved.J. C. H, Mingaye has made a study of several methodsof estimating thorium in monazite, and one of his conclusions isthat Haber’s metliod,14 precipitation as basic acetate, is rapid andsufficiently accurate. For this purpose, R. J. Meyer and M.Speter15 make use of the fact that thorium iodate is insoluble innitric acid provided that an alkali be present in excess. For theestimat.ion of cerium in cerite or monazite, F. J. Metzger andM. Heidelberger l6 apply the method previously described,l7 namely,oxidation with sodium bismuthate, reduction of the ceric salt withferrous sulphate, and titration of the excess of the latter withpermanganate.A.Gemme1118 has improved H. D. Newton’s volumetric methodof estimating titanium. He employs an alloy of aluminium andmagnesium (‘( magnalium ”), or preferably a zinc-aluminium alloy,as reducing agent. The latter alloy reduces ferric salts immediatelyat 40-50°, but thirty t o forty-five minutes are required for thereduction of titanium salts. By taking advantage of these facts,Amer. J. Sei., 1871, [iii], 1, 296.Zeitsch. anal. Chem., 1910, 49, 158 ; A., ii, 348.Chesn. News, 1910, 101, 54 ; A., ii, 347.Ann. Report, 1908, 193.lo 0. M. Shedd, J. Ind. Ens. Chem., 1910, 2, 379.11 Trans., 1910, 97, 1408.l2 Ann.Zeport, 1909, 146.l3 Becords GeoZ. Survey, N. 23. Wales, 1909, 8, 276; A , , ii, 78,l4 iClo?zats?b., 1897, 18, 687 ; A., 1898, ii, 295.l5 Chem. Zeit., 1910, 34, 306 ; A., ii, 459.J. Amcr. Chem. Soc., 1910, 32, 612; A., ii, 656.Ann. Rcport, 1909, 146.I8 Analyst, 1910, 35, 198 ; A, ii, 899ANALYTICAL CHEMISTRY. 169he estimates iron and t'itanium in a mineral by double titration withpermanganate. 0. L. Barnebey and R. M. Isham19 describe arapid and accurate method of estimating titanium in presence ofiron. The latter metal is extracted by ether as ferric chloride, andthe titanium is precipitated as dioxide in acetic acid solution.Traces of titanium, after separating the iron in the mannerdescribed, may be estimated tintometrically with hydrogen peroxide.P.E. Browning and H. E. Palmer20 estimate vanadium as silvermetavanadate by addition of silver nitrate to a neutral solution.The chemistry of osmium and its estimation is dealt with in apaper by 0. Ruff and F. Bornemann.21 Instead of separatingniobium and tantalum, the oxides of the two metals may beweighed together, and their relative amounts calculated from thespecific gravity of the mixture.22It is shown by L. Rossler23 that gold may be precipitated fromits solutions as metal by addition of alkaline hydrogen peroxide.J. C. H. Mingaye24 states that as little as 0.06 gram per ton ofplatinum in alluvial deposits may be estimated tintometrically withstannous chloride.The remarkable accuracy attained at the Royal Mint in thoassay of gold bullion is shown by J. Phelp~,~5 who arrives at theconclusion that the error for the mean of, say, 20 assays madewith the greatest care should not exceed 0.01 per 1000.The iodoeosin method of measuring the alkalinity of glass wasfirst described by F.Mylius in 1889, and since then numerouspapers on its application have been published by the same authorand his collaborators. It has been found that the tendency ofglass to disintegrate (" weathering " tendency), either by the actionof liquid reagents or by exposure to the air, as measured by thismethod, enables glasses t o be classified into three types: (a) Lightglasses which show little, if any, increase in alkalinity after" weathering "; (6) light glasses (used with due protection foroptical purposes), which show a very large increase in alkalinityafter weathering; ( c ) heavy optical glasses which show EL decreasein alkalinity after " weathering." 2619 J.Arner. Chem. SOC., 1910, 32, 957; A., ii, 901.2o Amer. J. Sci., 1910, [iv], 30, 220 ; A , , ii, 902.a1 Zeitsch. anorg. Chem., 1910, 65, 429; A., ii, 305.H. Mr. Foote and R. W. Langley, Amer. J. X c i . , 1910, [iv], 30, 393; A.,1911, ii, 71.23 Zeitsch. anal. Chem., 1910, 49, 739 ; A., ii, 1115.24 Record Geol. Survey, N. 8. Wnles, 1909, 8, 276 ; A . , ii, 78.25 Tra?zs., 1910, 97, 1272.26 Zeitsch. nnorg. Clmit., 1910, 67, 200 ; Ber., 1910, 43, 2130 ; A , , ii, 656170 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Electrochemical Analysis.A great deal of useful work has been done during the year onthis branch of analytical chemistry.I n the first place, a reporthas been issued by the Electro-Analysis Committee of the BritishAssociation for the Advancement of Science. I n it the work ofF. M. Perkin and W. E. Hughes, and of H. J. S. Sand is discussed.The latter chemist, it is stated, has obtained satisfactory resultsfor copper with a cathode of silver, and for zinc with a cathode ofnickel. It has been found that chlorides exert a retarding influenceon the deposition of copper, owing to the formation of derivatives ofcuprous chloride, from which the copper is only deposited at a highpotential. Alloys containing copper, antimony, and tin have, it isstated, been satisfactorily analysed. When lead is present, it maybe deposited with the tin, but means of separating the two whenthis occurs have been found.A review on the progress of electro-analysis has been published by A. Stahler,27 whilst another reviewhas been published by the same chemist, in which special referenceis made to rapid methods with rotating electrodes and solutions.28F. Foerster 28a deals similarly with the work carried out during theyear 1909.Last year, it will be remembered that J. Stoddard29 showed thatseveral metals can be deposited rapidly and completely with theuse of stationary electrodes and strong currents, the latter causingthe solution to be agitated by the vigorous gas evolution. Heemployed a platinum gauze cylindrical cathode and a mercurycathode. The experiments with the platinum cathode have beenrepeated by T.S. Price and T. C. Humphreys,30 who find that forrapid electro-analysis stationary electrodes are less trustworthy thanrotating electrodes. On the other hand, R. C. Benner31 hasrepeated Stoddard’s experiments, using a mercury cathode, and hisresults show that with copper, silver, cadmium, and bismuth, themethod is almost as rapid as when a rotating anode is used, andthat the results are as accurate as those obtained by other methodsin which mercury is employed as a cathode.32 F. M. Perkin andW. E. Hughes33 describe various forms of rotating electrodes forthe rapid deposition of metals. They recommend a rotating anode,consisting of a closely wound spiral of iridio-platinum wire and aFortschr.Chem. Phys. undphys. Chem., 1910, 2, 215.‘Is Zeitsch. Elcktroehem., 1910, 16, 551.30 J. Soc. Cham. Id., 1910, 29, 307 ; A., ii, 446.31 J. Amer. Chem. SOC., 1910, 32, 1231 ; A., ii, 999.az Compare also W. S. Kimley, ibid., 637 ; A., ii, 654.38 Trans. Faraday Soc., 1910, 6, 1 4 ; Chem. News, 1910, 101, 52; A., ii, 898.Ibid., 826. 2) Ann. &port, 1909, 151ANALYTICAL CHEMISTRY. 171cylindrical stationary cathode of platinum gauze of fine mesh.Some important new apparatus for the rapid estimation of metalswas described by H. J. S. Sand and W. M. S,malley a t a meetingof the Faraday Society on December 10th. The electrodes aresimilar to those designed by Sand in 1907 and 1908, and the anoderequires only about 5 grams of platinum.H. J.S. Sand34 gives some further details of his method ofestima-ting lead as dioxide.35 Other facts concerning the methodare published by R. C. Benner,36 who confirms the accuracy ofSand’s results. B. Pasztor 37 deals with the rapid estimation of tinwith varying strengths of current, different temperatures, anddifferent electrolytes. A very useful paper on the conditionsaffecting the electrolytic estimation of copper is published byW. C. Blasdale and W. C r u e ~ s . ~ ~It has been found that high results are invariably obtained inthe electrolytic estimation of zinc,39 and that this is due to thedeposition of hydroxide along with metallic zinc.40 The advantageof employing certain organic electrolytes in the estimation ofcadmium has been pointed out by the Misses M.E. Holmes andM. V. Dover.41 A rotating anode is employed with a current belowone ampere. Cadmium formate in presence of calcium acetate andlactate gave good results, whereas the acetate and lactate electro-lytes alone were less successful. Useful data are given on theelectrolytic separation of several metals by J. H. Buckmaster andE. F. Smith.42 A paper has appeared on the estimation of tin inbrass and other all0ys,~3 and another on the estimation of tin inwhite meta1.44 Miss L. G. Kollock and E. F. Smith45 show thatfrom a solution containing a little free acid and 0.2 gram of indiumsulphate, metallic indium may be rapidly and completely depositedwith the use of a mercury cathode in conjunction with a rotatinganode.The total dilution is 10 C.C. ; the current 2 - 4 amperes at anE.M.F. of 7.5 to 6.5 volts.Last year it was shown by F. A. Gooch and H. L. Read46 that.34 Trans. Faraday SOC., 1910, 5, 207 ; A., ii, 456.35 Ann. Report, 1909, 151.37 Elektrochem. Zeit., 1910, 16, 281 ; A., ii, 459.38 J. Amer. Chem. SOC., 1910, 32, 1264; A . , ii, 1112.s9 E. B. Spear, E. E. Wells, and B. Dyer, ibid., 530 ; A , , ii, 455.40 E. R. Spear, ibid., 533 ; A . , ii, 455.Ibid., 1251 ; A., ii, 1111.42 Bid., 1471 ; A., ii, 1112.E. Schurmann and H. Arnold, Mitt. K. nfaterialpriifungsamt., 1909, 27, 470 ;J. Inti. Eng. Chem., 1910, 2, 348.A., ii, 549.44 E. Schurmann, Chenz. Zeil., 1910, 34, 1117 ; A . , ii, 1115,45 J. Amer. Chenz. Soc., 1910, 32, 1248 ; A., ii, 1000.*6 Amer.J. Sci., 1909, [iv], 28, 544 ; A , , ii, 67172 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTHY.the estimation of chlorine in hydrochloric acid with the use of a,silver anode gives low results, owing to the passage of silver fromthe anode t o the cathode, and t o the formation of hypochlorousacid. These chemists employed a platinum cathode, and theirresults have been confirmed by J. 8. Goldbaum and E. F. Smith,*7who find, however, that with a rotating silver anode and a mercurycathode a high degree of accuracy may be attained.Organic Chemistry.QuuZitatiue.--There arO but few papers in this category whichdemand notice. I n the course of his studies on the photochemicalsynthesis of formaldehyde in green plants, S.B. Schryver48 hasincreased the sensitiveness of Rimini's phenylhydrazine test forformaldehyde. He shows that it is specific, and that the intensity ofthe coloration gives an indication of the actual quantity. Someuseful suggestions are made by G. Denigks49 on the detection oftraces of formaldehyde by Schiff's reagent. He uses this reagentfor t'he detection of methyl alcohol in presence of ethyl alcohol,the mixture being first treated with permanganate and the excess ofthe latter destroyed.50For the detection of trichloroacetic acid by the formation ofchloroform, R. Stoll6 5 l suggests heating with antipyrine instead ofwith potassium hydroxide or aniline. The former causes theevolution of chloroform from chloral hydrate, whilst the odour ofaniline might mask that of chloroform.In 1891, Janovsky showed that sodio- or potassio-acetone givescolour reactions with aromatic dinitro-compounds, and in thefollowing year von Bitto observed that the same reagent might beused as a test for aldehydes and ketones.As indicating themechanism of the reaction, F. Reitzenstein and G. Stamm 52 bringforward evidence that the compound formed in the case of 1-chIore2 : 4-dinitrobenzene is probably the condensation derivative,CH,:CMe*O*C,H,(NO,),. A tabulated list is given of the colorationsobtained by several dinitrecompounds, aldehydes, and ketones byJanovsky 's reagent.Scatole may, it is said, be distinguished from tryptophan, indole,or 2-methylindole by the fact that when ilr solution even as diluteas 1 in 5,000,000 is mixed with 3 drops of methyl alcohol and 3 drops47 J.Amer. Chern. SOC., 1910, 32, 1468; A., ii, 1107.48 Proc. Roy. Soc., 1910, H, 82, 226 ; A . , ii, 334.49 Compt. rend., 1910, 150, 529; A . , ii, 357.6o Bid., 832 ; A . , ii, 461.51 Ber. Deut. pharm. Ges., 1910, 20, 371 ; A., ii, 1119.52 J. pr. Chem., 1910, [ii], 81, 167 j A,, ii, 358ANALYTICAL CHEMlSTRY. 173of sulphuric acid, a violebred coloration is produced.53 Severalcolour reactions given by dried egg albumin and different reagentsare described by C. Reichard.54W. Harrison55 has drawn the conclusion that the bluecoloration of iodine with starch is merely a colloidal solution ofiodine, the starch acting as a protective colloid. His further con-clusion that the dextrins and ‘‘ starch celluloses ” ( ?) are all differentcolloidal states of starch and not chemically different compoundsis one which does not appaar to be supported by any evidence.Quantitative.Ultimate ,4nalysis.--It is well known that the estimation ofcarbon and nitrogen in anthracene derivatives and other complexaromatic compounds of high molecular weight is attended withdifficulty.The subject is dealt with by R. Scho11,56 who recom-mends Dennstedt’s methods. For nitrogen, he prefers a, methodwhich consists in placing about 1 gram of potassium chlorate in aboat in the fore part of the tube. After the main portion of thenitrogen has been evolved, this chlorate is ignited until the copperspiral commences t o blacken. I n these circumstances, no oxygenneed gain access t o the azotometer.The allegation of H. Wei1,57that lead peroxide retains carbon dioxide, has been shown byM. Dennstedt and F. Hassler 58 to be unfounded; but they pointout that the coinmercial product frequently contains organic matter.The estimation of carbon and hydrogen in the calorimetric bombis dealt with by H.. L. Higgins and Miss A. Johnson,sg and also byE. Grafe.Go J. Marcusson and H. Doscher 61 describe a modificationof the Hempel-Graefe method of estimating sulphur,fiz by means ofwhich the halogens may also be estimated.Commercid Products.Foods and Food Materials.-In 1898, J. L. Baker and the writerrecommended the use of invertase instead of acid for invertingsucrose in commercial products when carrying out the Clergetmethod, and this has been further worked out by C.S. Hudson.6353 T. Sasski, Biochem. Zeitsch., 1910, 23, 402 ; A . , ii, 166.54 €’harm. Zeit., 1910, 55, 158; A., ii, 363.55 Proc., 1910, 26, 252.56 Ber., 1910, 43, 342 [footnote] ; A., ii, 285.67 Bhid., 149 ; A., ii, 242.n9 J. Amcr. Chern. Soc., 1910, 32, 347 ; A , , ii, 460.Biochem. Zeitsch., 1910, 24, 277 ; A . , ii, 460.Chem. Zeit., 1910, 34, 417 ; A,, ii, 543.58 Ibid., 1196 ; A., ii, 647.6* Zeitsch. nngew. Chem., 1904, 17, 616; A , , 1904, ii, 514.8s U. X. Depart. of Agic., Burem of Chemidry, Oircular No. 50174 ANNUAL REPORTS ON THE; PROGRESS OF CHEMISTRY.I n a paper read before the London Section of the Society of ChemicalIndustry on January Znd, 1911, further details of this method havebeen worked out by J.P. Ogilvie, whereby its accuracy has beenincreased. I n many respects it is to be preferred t o the acidinversion process. N. Deerr64 deals with the influence of thevolume of the lead acetate precipitate in the estimation of sucrose inmolasses by the Clerget process.65 For the estimation of sucrose inpresence of lactose, glucose, or fructose, it has been suggested to heatthe mixture with alkaline hydrogen peroxide and a little manganesedioxide, whereby it is said that the reducing and optical p-owersof the two latter sugars are destroyed, whilst sucrose is notaffected.66 Maltose must not be present. This method, and thatof heating with dilute sodium hydroxide to destroy reducing sugarsin presence of S U C ~ O S ~ , ~ ~ even if trustworthy, which is open todoubt, have no advantage over existing methods.It has beenproposed to estimate lactose and sucrose in mixtures by takingadvantage of the fact that the Bulgarian (lactic) organism convertslactose into lactic acid, whilst it is without action on sucrose.68 Ithas also been shown that lactose may be estimated in admixturewith the commonly occurring fermentable sugars by fermenting asolution of the mixture with ordinary Sacchnromyces cereuisiae,the reducing power of the solution after fermentation being dueentirely to la~tose.6~ A similar fermentation method of estimatinglactose in presence of other sugars has been used by the writer withsatisfactory results. For the detection of artificial invert sugar inhoney, Fiehe's resorcinol test, depending on the presence of13-hydroxy-&methylfurfuraldehyde, which is said to be invariablypresent in artificial invert sugar,irO has been confirmed.71 Lessvalue must be attached to tests for detecting natural honey, sincethey do not of necessity show the absence of the artificial productin mixtures.The novel suggestion has been made of distinguishingnatural honey by a physiological (serum) test,72 and it has also beenproposed to characterise natural honey by determining its catalyticand diastatic powers,73 a method which may perhaps permit oftj4 Bull., 31, 1910 ; Agric. und Chem. Series: Expl. Station, Hawaiian XugnrPlanters' As.roc. 6b Compare L. Eynon, Ann.Rcport, 1909, 158.P. Lemeland, Ann. Chim. anal., 1910, 15, 415; A., ii, 1007.67 A. Jolles, Zeitsch. Nnhr. Genussna., 1910, 20, 631 ; A., 1911, ii, 74.68 G. Bertrand and F. DuchLEek, Compt. rend., 1909, 148, 1338 ; A., 1909, i,89 J. L. Baker and H. F. E. Hulton, Analyst, 1910, 35, 512 ; A., 1911, ii, 74.70 Zcitsch. Nahr. Centism., 1908, 16, 75.71 Witte, ibid., 1909, 625 ; F. Reinhardt, ibid., 1910, 20, 113 ; and F. Muttelet,72 J. Langer, Arch. Hpgicm, 1910, 71, 308.73 A. Auzinger, Zcitsch. Nahr. Oenussm., 1910, 19, 65.623 ; L. Margaillan, ibid., 1910, 150, 45 ; A., ii, 163.Ann. Fakif., 1910, 3, 206 ; A., ii, 660ANALYTlCAL CHEMISTRY. 175quantitative expression. It is worthy of note that the presence offormaldehyde in sugar-cane juice and in sugar house products h abeen established.74 The suggestion to employ a solution of phenyl-hydrazine in sulphurous acid instead of the base itself on the groundthat it yields purer osazones with the sugars appears well worthy ofthe attention of analytical chemists.75Now that it has been shown by Chapman76 that the Jaff6reaction between creatinine and picric acid is simply one ofreduction of the latter, it has become very important actually toestablish the presence of creatinine in the case of assays carried outby the Jaff6 method, and some useful data for the isolation ofcreatinine from meat extracts have been published.77R.R. Tatlock and R. T. Thompson 78 have communicated a usefulpaper giving the composition of coffee of various origin and chicory.They suggest calculating the percentage of chicory in mixturesof that substance with coffee from the percentages of caffeine andash.I n the writer’s opinion, the data brought forward areinsufficient.At$tention has been called to the fact that salicylic acid is a normalconstituent of frlrits and wines. The amount normally presentin wines is said to be 0.001 gram per litre.79 An important paperon the estimation of salicylic acid in jams, etc., by a modificationof Harry and Mummery’s method has appeared.80 A substanceresembling Brandt’s maltol has been discovered in baked bread andbiscuits, and, like maltol, it gives a colour reaction with ferric salts,so that it is liable to be mistaken for salicylic acid.81Miss M. E. Pennington and A.D. Greenleea2 have applied amodification of Folin’s method to the estimation of loosely-combinednitrogen in flesh. I n the case of fowls, this percentage of nitrogenis shown to increase even when kept in cold store.Brugs, Alkaloids, Etc.-For the estimation of starch in mustard,H. Kreis 83 recommends a modification of Mayrhofer’s method ofisolating the starch and weighing it as such.Certain modifications in the Codex method of estimating caffeine74 P. A. Yoder and W. G. Taggart, J. 2nd. Eng. Chem., 1910, No. 6 ; Chem.75 J. Boeseken, Chem. Weekblad, 1910, 7 , 934 ; A, ii, 1118.77 K. Micko, Zeitsch. Nahy. Genussm., 1910, 19, 426 ; A., ii, 557.78 J. SOC. Chem. Ind., 1910, 29, 138.79 H. Pellet, Ann.. Chiin. anal., 1910, 16, 302 ; A., ii, 906.* Zeitsch.Nahr. Gr?nuss?n., 1910, 20, 63 ; A , ii, 906.a1 A. Backe, Compt. rend., 1910, 150, 5 4 0 ; A., i, 225.82 J. Amcr. Chem. SOC., 1910, 82, 561 ; A., ii, 449.PB Chem. Zeit., 1910, 34, 1021.News, 1910, 102, 26.Ann. Keport, 1909, 159176 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in cola have been suggested by Desvignes.84 E. Bierling, K. Pap,and A. Viehover 85 have investigated the methods which have beenproposed for the evaluation of coca leaves, and make some definiterecommendations.P. van der Wielens6 describes methods for the estimation ofmorphine, narcotine, and codeine in opium and its galenical p r eparations. A critical review of the methods of testing digitalispreparations is published by C. Fo~ke,~' and he has further developedthe physiological method of testing both digitalis and strophanthuspreparations.88 J.Burmann, jun.,89 brings forward evidence thatthe scwalled physiological titration method is inferior to thechemical methods for determining the value of digitalis preparations.The titration of alkaloids with different indicators is dealt withby E. Runne,go whilst the difficulties attending this are pointed outby E. Elvove.91 Elvove suggests titrating the hydrochlorides byVolhard's method after previously washing them with alcohol.F. H. Carr and W. C. Reynolds 92 have re-determined the specificrotatory power of I-hyoscyamine in 50 per cent. alcohol, and obtainedthe value [a],, - 2 2 O . The d-base gave a slightly lower result,probably owing to racemisation.The rotatory power is not affectedby concentration, but the influence of temperature is not mentioned.The paper contains a number of valuable observations on therotatory powers of different alkaloids and their salts, and aIso of theinfluence of different solvents. One of the most striking observationsis that hydrastine has a strong dextrorotation in 50 per cent.alcohol, is optically inactive in 95 per cent. alcohol, and laevorotatoryin absolute alcohol.According to F. Klein,Q3 when a trace of sodium selenite is addedto a solution of an alkaloid in 94 to 95 per cent. sulphuric acid,colorations are produced by means of which several alkaloids maybe distinguished.For the production of the red coloration with adrenaline,potassium persulphate is said t o be preferable to other oxidisingA solution of vanillin in alcohol containing a little hydro-.7.Pharm. Chim., 1910, [vii], 2, 20; A , , ii, 763.Arch. Pharm., 1910, 248, 303.86 Bull. Sci. PJmrmacol., 1910, 17, 59 ; A., ii, 558.87 Arch. Pharm., 1910, 248, 365.89 Schweiz. Wocfiensch. Chem. und Pharnt., 1910, 48, 410.WJ Apoth. Zeit., 1909, 24, 662 ; 1910, 25,137 ; A., ii, 362.91 J. Amcr. Chem. Soc., 1910, 32, 132 ; A,, ii, 361.WJ J. Ind. Eng. CJLem., 1910, 2, 389.e4 A. J. Ewins, J. Physiol., 1910, M, 317 ; A,, ii, 557.Ibid., 345.Tra?is., 1910, 97, 1328ANALYTICAL CHEMISTRY. 177chloric acid is said to give a colour reaction with 0.00095 gramof antipyrine, but iiot with pyramidone.95The assay of anhydromethylenecitric acid, its sodium salt,‘‘ citarine,” and its compound with hexamethylenetetramine(“ helmitol ”) is dealt with by J.M. A. Hegland.96Fats und Oils.-The comparatively recent introduction of cocoanutoil and of palm kernel oil as materials for the manufactureof margarine renders it important that the methods ofdetecting and estimating these in presence of other fats should bemade as precise as possible. One of the most valuable tests fordistinguishing between butter fat and the fats above named isthat of Polenske, and in this connexion attention may be drawnto a paper by S. H. Bli~hfeld.~’ H e has devised an apparatuswhich overcomes the difficulty in the Polenske method of theinsoluble acids settling on the condenser tube. He shows that thepercentage of the soluble and insoluble silver salts of the volatilefatty acids affords valuable data for the estimation of the above-named fats in admixture with butter.The method proposed byE. Ewers,g* which is based on the different solubility in water ofthe magnesium salts of the fatty acids, and on the different solu-bility in light petroleum of the fatty acids from the solublemagnesium salts, is likely to prove useful, as are also the twomethods proposed by G. Fendler.99 One of these depends on thedifferent solubility of the fatty acids in 60 per cent. alcohol, and theother on the fractional distillation of the ethyl esters of the fattyacids.1 M. Raffo and G. Foresti2 describe a viscometric method bymeans of which they claim that 10 per cent. and upwards ofmargarine in admixture with butter may be rapidly and accuratelyestimated. The instrument employed is Ostwald’s viscometer.G.Dumitrescu and D. M. Popescu 3 recommend taking the refractiveindex of the insoluble fatty acids of butter in order to detectsophistication with foreign fats.A series of investigations has been published on the analysisof wool grease, “ oleine.”4 It is shown that cholesterol is eitherabsent or present only in traces, and methods are described forthe detection and estimation of mineral and rosin oils in admixture95 C. Primot, Bull. Sci. Phnrmncol, 1909, 16, 270 ; A., ii, 83.96 Phnm. WeekbZad, 1910, 47, 418 ; A . , ii, 555.97 J. SOC. Chem. Ind., 1910, 29, 792.98 Zeitsch. Nahr. Genussm., 1910, 19, 529.Bcrlin, 1908, see Chem.Zentr., 1908, ii, 911).99 lbid., 545.This paper was, however, published in 1908 (ArBeitcn. €‘harm. f m t . Univ.Cazzetta, 1909, 39, ii, 441 ; A., ii, 360.Ann. Falsif., 1910, 3, 149; A., ii, 556.J. Marcusson, Mitt. K. MateriaZpr.iiLficngsamt., 1910, 28, 469 ; G. WinterfeldandW.Mecklenbnrg, ibid., 471 ; G. Winte~feld, ibid., 474.REP.-VOL. VII. 1’78 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.with the above-named ( ( oleine.” For the detection of fish oils invegetable oils, advantage has been taken of the fact that thebromides of the former are insoluble, and of the latter soluble inc hlorof orm.5Halphen’s test for cottonseed oil is said to be rendered muchmore sensitive when the mixture of oil and reagent is heated in asealed tube a t 12OO.S It has been found that other alcohols maybe substituted for amyl alcohol, which is usually employed in thistest, but that without any alcohol no coloration appears until theheating has been continued for fifteen minutes, and it is suggestedthat this may be due to the presence of glycerol produced byhydrolysis.It has also been found that the solution of sulphur incarbon disulphide cannot be replaced by thiocyanates, xanthates, orother sulphur compounds.7For the detection of rape oil or of any oil derived from thecruciferae in admixture with other oils, methods depending on theisolation of erucic acid have been proposed.8 There has been someconfusion in the literature between Chinese and Japanese woodoils, both being designated in the trade as Tung oil.A. Kreiken-baum 9 gives some constants of the Chinese product.It has recently been shown that drying oils give a primary andsecondary bromine value, whilst non-drying oils absorb the fullamount of bromine at once.loFermentation Products.-Under the name of “urotropine,” hexa-methylenetetramine is being added t o wines to remove the excess ofsulphurous acid in them. It appears merely to mask the sulphurousacid by the formation of the compound with formaldehyde. Whena wine so treated is distilled with sulphuric acid, formaldehydepasses over, and may be detected by the ordinary reactions.11The method of estimating tartaric acid in natural productsdescribed by C. Beys 12 appears useful and accurate.P. Carles hasconducted a useful investigation of the methods for the analysis of0. Eisenschinil an(l H. N. Copthorne, J. Ind. Eng. Chenl., 1910, 2, 43.‘j R. Marcille, Ann. Falsif., 1910, 3, 235.7 L. Rooenthaler, Zeitsch. Nahr. Genzmsnt., 1910, 20, 453 ; A., ii, 1123.8 D. Holde and J. Marcurson, Zeitsch. angew. Chew., 1910, 23, 1260 ; Chew.10 W. Vaubel, Zeitsch. angew. Chem., 1910, 23, 2077 ; 2078 ; A., ii, 1122.11 Rouillard and Goujon, Ann. FaZsiy., 1910, 3, 14 ; A., ii, 239 ; G . Denigks,Compt. rend., 1910, 150, 529 ; A., ii, 357 ; A. Hubert, Ann. Chim. anal., 1910,15,100; A., ii, 465 ; Ronis, Ann. FaIsiJ, 1910, 3, 106 ; A . , ii, 466 ; H. Fonzcs-Diacon, Bull. SOC. chim., 1910, [iv], 7, 389 ; A., ii, 662 ; E. VoisBnet, Compt.rend., 1910, 150, 879 ; A., ii, 466 ; L.Snrre, Ann. Falsif., 1910, 3, 292 ; A., ii,808.l2 Compt. rend., 1910, 150, 1250 ; Bull. SOC. chim., 1910, [iv], 7, 697; A.,ii, 662, 758.Zeit., 1910, 34, 689. J. Ind. Eng. Chrn., 1910, 2, 205ANALYTICAL CHEMISTRY. 179tartrates adopted by the Seventh International Congress of AppliedChemistry.13According to G. Meillhre and P. Fleury,l4 inositol may be isolatedfrom various fermented liquids, as also from animal fluids and plantjuices by precipitation with basic lead acetate, copper acetate, etc.P. Fleury15 proposes to identify wine vinegars by the presence ofinositol. He does not mention, however, whether he has proved theabsence of inositol in other fermented vinegars, for example, maltvinegar.The suggestion has been made by A.Rusconi16 to detect saponinin beers, aerated waters, and wines by hzmolysis.A modification of the Allen-Marquardt method of estimatinghigher alcohols in potable spirits has been described by A. Lasserre,17whereby propyl alcohol is excluded. The principle of the methodis that the sample is extracted with carbon disulphide in presenceof saturated sodium chloride solution, and the extract oxidised.Turpemt ine, Petroleum, and o t 72 er 0 rganic Product s.-In thecontracts laboratory of the United States Bureau of Chemistry, alarge number of commercial materials and products are examined,and the methods which have been found most useful are describedby P. H. Walker.19 The methods which deal with the analysis ofpaints, pigments, and paint materials, inks, “ glycerin,” lubricatingoils, glue, rubber, disinfectants, pipe covering and cement, and soaps,although in many cases not new, are valuable inasmuch as theiraccuracy has been so thoroughly tested.A modification of H.E. Armstrong’s well-known method ofestimating turpentine and petroleum in mixtures 19 has beendescribed by R. S. Morrell.20 He obviates the difficulty of separatingthe petroleum from the polymerised turpentine by distilling themixture direct with steam, when the petroleum passes overquantitatively. The method is said to be accurate to within 2 percent. For the estimation of petroleum and resins in turpentineoils, P. Nicolardot and L. Clement 21 add nitric acid to a solution ofthe sample in glacial acetic acid, and distil.The turpentine isdestroyed, petroleum passes over, whilst the residue contains theresins. E. Louise22 has further developed his method of analysisBull. SOC. chim., 1910, [iv], 7, 586 ; A., ii, 758.l4 J. Pharm. Chiin., 1910, [vii]. 1, 348 ; A . , ii, 553.l5 Ibid., 2, 264 ; A., ii, 1006.l6 Boll. Xoc. Med. Chir. Pavia, 1910 ; A., ii, 559.Ann. Chim. anal., 1910, 15, 335 ; A., ii, 1005.18 Bulletin Avo. 109, U.X. Dnpartnient of Agriculture, Burcau of Chemistry ; seelY J. SOC. Chem. bzd., 1882, 1, 478.21 Bull. SOC. chim., 1910, [iv], 7, 173 ; A., ii, 460.also Chcm. n’ews, 1910, 102, Nos. 2643-2658.2o B i d . , 1910, 29, 241.Cowapt. rend., 1510, 150, 526 ; A . , ii, 357.N 180 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.by miscibility curves, and applied i t to the estimation of petroleumand rosin oils in turpentine.Aniline is used to mix with the sample.The method is applicable to the analysis of alcohols, perfumes,etc.23I n a series of papers on the digestion of cellulose by domesticanimals,24 i t is shown among other things that Simon andLohrisch’s 25 method of estimating cellulose gives low results. Anew method of estimating cellulose has been devised by R.Dmochowski and B. Tollens.26 A. Gr6goire and E. Carpiaux 27describe an apparatus for the estimation of cellulose by Hennebergand Stohmann’s method. For the estimation of the degree oftannage of leather, the methods have1 been revised by J. G. Parkerand 31. Pau1.28A gricultu ral Chemistry.L. E.Cavazza29 proposes to estimate tho alkali metals in soilvolumetrically as carbonates. The soil is first extracted withhydrochloric acid, and the extract repeatedly evaporated withoxalic acid until all the hydrogen chloride has been expelled. Theresidue is then ignited, and the soluble portion titrated. BiBler-ChatelanFO for the estimation of the available potassium in soils,recommends extracting with water saturated with carbon dioxide.Densch 31 has reinvestigated his method of estimating nitrogen insoils. For the total nitrogen any nitrite present is first oxidisedwith permanganate and sulphuric acid. Reduction is next effectedby ferrum redactum or zinc dust. The remainder of the operationis the same as in Kjeldahl’s method.The author claims that hismethod so modified is just as accurate as that of Mitscherli~h.~ZThis last-named method is adversely criticised by T. Zeller.33A scheme for the estimation of different nitrogenous substancespresent in bone superphosphate is published by G. Chardet.3423 Compare also M. Vkzes, Conzpt. rend., 1910, 150, 698 ; A., ii, 461.24 A. Scheunert, E. Liitsch, and W. Grimmer, Bcrl. Tieriirxtl. Wochensch., 1909,25 Zeitsch. physiol. Chem., 1904, 42, 55 ; A., 1904, ii, 787.a J. Landw., 1910, 58, i, 21 ; A., ii, 554, 555.27 Bull. Soe. chim. Belg., 1910, 24, 217 ; A . , ii, 661.29 Alba. Scuola Yitic. End. Jan., 1910; A., ii, 453.30 Contpt. rend., 1910, 150. 716 ; A, ii, 453.31 Chem. Zcit., 1909, 33, 1249 ; A., ii, 70.33 Landw.Vemuchs.-Stut., 1909, 71, 437 ; A., ii, 70.a4 Ann. Chim. anal., 1910, 15, 215; A., ii, 652.25, 826, 867 ; 1910, 26, 113, 152 ; A., ii, 554.J. Xoc. Chem. Ind., 1910, 29, 315.32 Ann. XppoTt, 1909 157, 158ANALYTICAL CHEMISTKY. 181Water Analysis.In connexion with the estimation of nitrates by the Grandval andLajoux method, E. M. Chamot and D. S. Pratt have continuedtheir interesting researches’35 and they find 36 that the coloration isdue to the formation of tripotassium 6-nitrophenol-2 : 4-disulphonate.A careful study of the influence of different quantities of chlorideson this method has been made by R. Stewart and J. E. Greaves.37It has been pointed out that nitrites in presence of chlorides enhancethe coloration given by nitrates in the Grandval and Lajouxmethod.38 For the estimation of nitric nitrogen, Salle 39 recommendsreduction with zinc dust and ferrous sulphate in presence of sodiumhydroxide, and the accuracy of this method has been confirmed byC.Frabot’40 who finds that reduction by aluminium in alkalinesolution is also trustworthy.A. Vesterberg 41 has applied Winkler’s volumetric method ofestimating carbon dioxide t o a number of cases. With naturalwaters containing magnesium, the precipitation of magnesiumhydroxide is a disturbing factor, but this is said to be overcomepartly by adding a certain quantity of sucrose.It has been shown by M. T. Lecco& that for the estimation oflithium in waters, the Meyer-Fresenius method gives results accuratewithin k3 per cent.Physiological Chemistry.A mko-compounds.-The very useful Sachsse-Kormann process forthe estimation of aliphatic amino-groups was improved by HoraceT.Brown and his collaborators some years ag0.~3 It has beenfurther modified by D. D. van Slyke,44 and in the apparatus whichhe describes an estimation can be made in a few minutes to a degreeof accuracy amounting to +0*05 milligram of nitrogen.Increasing use is being made of Sorensen’s formaldehyde methodof estimating amino-nitrogen in physiological liquids, and some mostimportant papers on the subject have appeared during the year.4535 Ann. Report, 1909, 153.36 J. Amer. Chem. Soc., 1910, 32, 630 ; A., ii, 545. 37 Ibid., 756 ; A., ii, 652.38 L. Farcy, BUZZ. SOC. chim., 1909, [iv], 5, 1090, 1091 ; A., ii, 72 ; J.Pouget,39 Ann. Chim. anal., 1910, 15, 103 ; A., ii, 451.41 Zeitsch. physikal. Chem., 1910 ; 70, 551 ; A., ii, 345.a2 Zeitsch. awl. Chem., 1910, 49, 286 ; A . , ii, 453.43 Trans., Guinness Research Laboratory, 1903, 1, 29. 44 Ber., 1910, 43, 3171.45 V. Henriques and S. P. L. Sorensen, Zeitsch. phy,&oZ. Chem., 1909, 63, 27 ;1910, 64,120 ; A . , ii, 164, 456 ; 0. von Spindler, Schweiz. Wochensch. Chem. undibid., 1910, [iv], 7, 449 ; A., ii, 652.Ibid., 209 ; A., ii, 652182 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Attention has been drawn to the necessity of removing carbonatesand phosphates previous to titrating a liquid by this method.46The fact that many physiological liquids are coloured is a seriousdifficulty in the application of Sorensen’s method, and an apparatus(consisting of glass cells illuminated from below), in which it isstated these titrations can be carried out with sufficient accuracyt o justify the ionic concentration being calculated, should proveusefu1.47Proteim.-Certain proteins of animal origin have been shown togive an intense purple coloration with sodium nitroprusside andammonia which is discharged with acetic acid, and since thisreaction is not given by egg albumin until it has been submitted topeptic digestion, it is surmised that it is due to hydrolysed productsof the proteins-organ-peptides.48 Acetone has been suggested asa precipitant for proteins in milk and bl00d.49 For the estimationof albumin in urine, a method consisting in precipitating withpicric acid, centrifuging, and measuring the depth of the precipitateis rapid, and probably accurate enough for the purpme.50An adiabatic calorimeter for use with the Berthelot bomb inconnexion with the determination of the potential energy of food,faeces, and urine has been devised by F.G. Benedict and A. L.Higgi11s.5~Enzymes.--A remarkable number of papers dealing with enzymeshas been published during the year, but only those which apply toanalytical chemistry-perhaps by no means the best-can benoticed here. The writer had occasion to point out, in the 1;tstreport, that Harrison and Gair’s method of estimating the diastaticpower of malt extracts yields inaccurate results. Recently he haspublished experiments justifying this criti~ism.5~ He shows thateven the more recent modification of the method suggested byHarrison,53 although it yields better results, is nkt always quiteaccurate, since Kjeldahl’s law of proportionality is disregarded.PlLarm., 1909, 47, 767; A., 1910, ii, 419; H.B. Andresen and M. Lauritzen,Zeitsch. physiol. Chem., 1910, 64, 21 ; A., ii, 450.46 S. P. L. Sorensen, Bioch.cm. Zeitsch., 1910, 25, 1 ; A., ii, 556 ; H. Bla1f;tttiZeitsch. physiol. CJwm., 1910, 66, 152 ; A . , ii, 662; L. de Jager, ibid., 67, 1 ;A , , ii, 751.9 G. S. Walpole, Proc. physiol. h’oc., 1910 ; BiocJwn. J., 1910, 5, 207 ; A., ii,48 W. Arnold, Bull. Acad. Sci. Crucow, 1910, A, 56, 61 ; A., ii, 560.49 T . Weyl, Ber., 1910, 43, 508 ; Zeitsch. physiol.Chem., 1910, 65, 246 ; A., i,50 Aufrecht, Dezct. itled. Wochensch., 1909, 35, 2018 ; Phurm. Zeit., 1910, 65,31 J. Anzcr. Chem. Xoc., 1910, 32, 461 ; A , , ii, 391.5% Chemist and Druggist, 1910, 76, 924.541, 995.287, ii, 486.345 ; A., ii: 560, 663.53 See Ann. Report, 1909, 160ANALYTICAL CHEMISTRY. 183Further, he takes exception to Harrison’s practice of returningresults t o four figures, which the accuracy of the copper reductionmethod does not justify.54 H. C. Sherman, E. C. Kendall, andE. D. Clark55 find that the diastatic power of “taka diastase”may be determined by ascertaining the mass which, in thirtyminutes, acting on standard starch paste at 40°, causes thecomplete disappearance of the iodine reaction. They showthat the results run parallel with those obtained by the cupricreduction method when the conversion is kept within thelimits of Kjeldahl’s law.This is of great theoretical interest, asshowing that the hydrolysis of starch by the particular enzymemeasured by the disappearance of the iodine reaction is a linearfunction of the time or mass. I n order to measure the diastaticpower of pancreatin-amylase, both the cupric reduction and iodinemethods failed. The latter was found to give satisfactorv resultswhen the hydrolysis of the starch was carried out in presence ofsodium chloride and disodium phosphate.56 The inhibiting effects ofvarious reducing sugars towards the hydrolysis of starch by diastasehas been studied by A. Wohl and E. Glimm,57 who have obtainedsome interesting results.A rapid test for emulsin, depending uponits cyanogenetic function, has been devised by E. F. Armstrong.58This method will probably be useful to the analytical chemist whenemployed as a test for a cyanogenetic glucoside.J. Wohlgemuth59 describes a method for the estimation of theactivity of fibrin ferment, and of fibrin ferment in body fluids andorgans. E. Abderhaldenco proposes to detect enzymes in tissuesby the formation of tyrosine crystals when the tissues are kept fora few hours in solutions of silk peptone.I n order to estimate the activity of trypsin, A. Palladin61 hassuggested dyeing the protein with a substance such as “ spirit blue ”before acting on it with the trypsin; the tryptic action may bemeasured by the intensity of the coloration of the solution.Toxicology and Forensic Analysis.Some useful directions are given for the purification of reagentsHe states that he54 Compare A.R. Ling and G . C. Jones, Analyst, 1908, 33, 163; A., 1908,55 J. Amer. Chem. Soc., 1910, 32, 1073; A., ii, 1012.W Compare E. C. Kendall and H. C. Sherman, ibid., 1087 ; A., i, 799.5i Biochcm. Zeitsch., 1910, 27, 349 ; A., i, 799.5s Proc. shysiol. SOC., 1910, 33; A., ii, 668.59 Biochem. Zeitsch., 1910, 25, 79; A., ii, 664.61 P$iiger’s Archiv, 1910, la, 337 ; A , , ii, 912.62 Phrm. Post, 1910, 43, 233.employed in toxicological cases by E. Ludwig.62ii, 541.Zeitsch. physiol. Chem., 1910, 66, 137 ; A., ii, 666184 ANNUAL REPORTS ON THE, PROGRESS OF CHEMISTRY.has detected and estimated phosphorus in exhumed corpses six weeksafter burial.I n one case he found considerable amounts ofhydrogen cyanide four months after death, and in an exhumedcorpse nine months after burid atropine could be distinctlyrecognised. I n view of the tendency of formaldehyde to reactwith different compounds, its use for preserving fragments of organs,etc., would require great caution. It is shown by G. Venturoli andE. Ciacci63 that it prevents the recognition of cyanides, but not ofphosphorus or chloroform. In the case of most alkaloids, it exertsno influence, although morphine is mentioned as one which probablycondenses with it.The suggestion to volatilise mercury as metal by heating a sub-stance containing it with sodium formate in a current of hydrogen 64appears worthy of attention.M.T. Lecco65 states that in the examination of animal organsfor volatile poisons, such as phosphorus, the distillate, when oxidisedwith nitric acid, sometimes yields crystals of oxalic acid, which hefinds to be derived from alcohol.A very large number of papers have appeared during the yearon the detection and estimation of cyanides, and some of these areof more than usual importance. After Nietzki and Petri hadshown 66 that the isopurpuric acid of Hlasiwetz is dicganopicramicacid, it was obvious that the reaction of a cyanide with picric acidis attended by the reduction of the latter, yet this was not generallyrecognised. It has, however, been shown by A. C. Chapman67 thatunder the conditions of the tests for hydrogen cyanide by means ofpicric acid, the well-known coloration is due t>o reduction only.It is therefure not specific, and as a quantitative method must beregarded as empirical. This fa-ct detracts considerably fromthe value of the method of estimating hydrogen cyanide in bloodand tissues which has been proposed by A. D. Waller.68 J. Moirpoints out69 that in presence of copper acetate and acetic acid,the leuco-compound, hydroccerulignone (betramethoxydiphenol), isoxidised and coloured red by a trace of hydrogen cyanide. Othertetra-substituted diphenols, as well as benzidine, are said to givecolour reactions under the same conditions.E. Berl and M. Delpy 7O describe a method of estimating hydrogen63 Boll. Chim. Fcmn., 1910, 49, 129.6.1 A. C. Vouriiasos, Compt. Tend., 1910, 150, 922 ; A., ii, 549.G6 Uer., 1900, 33, 1788 ; A., i, 485.157 Analyst, 1910, 35, 469 ; A . , ii, 1119.G8 Proe. physiol. Suc., 1910, xlvii-xlis ; A., ii, 759.f)9 Proc., 1910, 26, 115.70 Ber., 1910, 43, 1430; A., ii, 661.Zeitsclt. anal. Chem., 1910, 49, 285 ; A., ii, 461ANALYTICAL CHEMISTRY. 185cyanide tintometrically as Prussian blue, whilst G. Lockemann 71gives directions for the detection of cyanides in coloured solution bythis reaction, and also by converting them into thiocyanates.The fact that the alkaloids can be precipitated by different nitro-phenols is discussed by L. Rosenthaler and P. Gorner.72 G. Jorgen-sen73 deals with the detection of morphine in animal organs andexcreta.I n connexion with the guaiacum test for blood, it has been pointedout that the delicacy is much increased if alcohol be used as wellas turpentine, and still further if the turpentine be replaced bysodium peroxide or sodium perborate.74 It has been suggested tosubstitute the benzidine test for the guaiacum in testing forThe statement of J. McWeeney,76 that this test as carried out byAdler is a valuable one for the detection of blood stains, has beendenied by F. Bordas,77 who points out that the reaction is obtainedwith many other colloids of animal and vegetable origin. He finds,however, that the method is applicable if the catalytic activity ofthe blood be restored by contact with pure cellulose (filter paperfree from iron) even after the blood has been heated to l l O o .Several papers have appeared on the hzmochromogen test forbi0od.78ARTHUR R. LING.'l Ber., 1910, 43, 2127 ; A., ii, 807.72 Zeitsch. anal. Chem., 1910, 49, 340 ; A . , ii, 557.73 Ibid., 484 ; A . , ii, 763.74 B. Bardachand S. Silberstein, Zeitsch. physiol. C 7 ~ n . , 1910, 65, 511 ; Chem.Zeit., 1910, 34, 814 ; A., ii, 664, 911 ; see also J. Krntter, Yierlelsjahrschr.ger. Med. ofe'entl. Sanitatswescn, 1910, 39, 42; A . , ii, 664.76 E. WaIter, Deutsch. Med. Wochensch., 1910, No. 7 ; A . , ii, 665.76 Sci. Proa. Roy. Dublin SOC., 1909, 12, 216 ; A., 1910, ii, 84.77 Compt. rend., 1910, 150, 5 6 2 ; A . , ii, 364.i8 Iialmus, Viertelsjahrschr. ger. Ned. ofentl. Savtitakwcsen, 1910, 39, 57 ;A., ii, 664 ; Mita, ibid., 64; A., ii, 665 ; Lochte, ibid., 6 6 ; A . , ii, 665

ISSN:0365-6217    

DOI:10.1039/AR9100700157

出版商:RSC    

年代:1910

数据来源: RSC

摘要:

PHYSIOLOGICAL CHEMISTRY.THE year 1910 which has just closed has not seen much change inthe personnel of the physiological world. Two eminent men, how-ever, have passed away, and the world is poorer by their absence.One of these is Pfluger, the celebrated head of the Bonn Laboratory.He was a prolific worker and a great fighter; no more shall wehave to record either his contributions to the science to which hedevoted his life, or the poIemical papers which issued from hisversatile pen. His name will live in the celebrated Journal whichhe founded, and which is now edited by his successor in the Bonnchair, Prafessor Max Verworn. The other loss we have to deploreis that of Dr. Sydney Ringer, whose important contributions tophysiological science in the midst of a busy life of medical practiceare now universally appreciated.Hardly a paper nowadays appearsin which Ringer’s solution does not find a mention.The names of new workers and writers will be found in our pages,but it is somewhat. sad to find that the number of the youngergeneration devoting themselves t o physiology and its branches is notso great as one would wish. The difficulty of finding demonstratorsin this subject, at any rate in this country, is one indication of thisfact. This is in part., but only in part, explicable by the foundationof the Beit Scholarships, which have snapped up some of the mostpromising of the younger men and women. The principal cause isthe belated discovery that physiology does not pay. With theexception of a few, a very few, professorships, the stipends consideredsufficient by Universities and similar institutions for the membersof their scientific staff are so parsimonious that it is no wonder thateven those who have special aptitude for scientific work cannotafford to relinquish more lucrative means of obtaining a livelihood.During the summer, the triennial meeting of the InternationalCongress of Physiology met at Vienna.It was a well-arranged andenjoyable reunion. As is usual in such meetings, the number ofpapers read was so great, that it proved a little difficult to see thewood because of the trees. Here, as in other recent physiologicalcongresses, the subject of biochemistry overshadowed the other sub-divisions of physiologyPHYSIOLOGICAL CHEMISTRY. 187The only new book which it is necessary to mention is a Handbookof Comparative Physiology, which is being issued in parts underthe editorship of Professor Hans Winterstein.It is a veryambitious undertaking, and first-class collaborators have beenpressed into service t o write the various articles. It is well knownhow much physiology is indebted to the frog for the extension ofour knowledge; frog’s muscles and the frog’s heart still remainthe object of attack in the investigation of many phenomena. Thus,Langley has this year published papers in relation to his theory ofreceptive substances, in which frog’s muscles have served for hisinvestigations on the action of nicotine and curare. Waller andVeley,2 also, have been using the same muscles for their work onvarious drugs, and many papers on the digitalis group of sub-stances have called the frog’s heart into requisition.3 There is,however, no need to multiply instances.During the year,also, papers on bees, fireflies, starfishes, and sea urchins will befound in our index. It is, in fact, becoming increasingly recognisedhow important comparative and even invertebrate physiology nowis; great light is shed by such work on vital problems as a whole,and even in many cases the facts so discovered may be applied tothe highest animals, man included. The maj0rit.y of physiologists,it is true, devote themselves more immediately to the considerationof the human subject, or of animals most nearly related to man.This is because the students they have to teach are mainly medicalstudents, and they are thus rightly forced to regard their subject asthe Institutes of Medicine, to use the old name by which physiologywas once labelled.Speaking for myself, this is the view ofphysiology in which I am most interested, as will be shown by sub-sequent portions of this report, in which I propose to consider atsome length certain pathological questions. It therefore came toone in the nature of a surprise, in looking through Winterstein’shandbook, to see how voluminous is the work already accomplishedin invertebrate fields; for example, in the article on nutrition andalimentation which Biedermann has contributed, there are somehundreds of bibliographical references in the section relating to thenutrition of insects alone.Turning now to periodical literature, one finds no abatement inthe monthly output of papers.I f anything, there has been an1 Proc. physiol. SOC., 1310, lix, J. Physiol., 40 ; A., ii, 797.2 Proc. physiol. Soc., 1999, xix, J. Physiol., 39; A., ii, 55. Proc. Roy. Soc.,1910, B, 82, 147 ; A., ii, 228 ; B, 82, 205 ; A., ii, 331 ; B, 82, 353 ; A., ii, 524 ;B, 82, 568 ; A . , ii, 986.3 See, for instance, Magnus and Miss Somtoii, Arch. expt. Path. Pharm., 1910,63,255; rl., ii, 986 ; Kasztan, ibid., 405 ; A., ii, 1094 ; Werschioin, ibid.,386 ; A.,ii, 1094 ; W. Straub, Biochem, Zeitsch., 1910, 28, 392 ; A., ii, 1094188 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.increase, i f one may judge by the number of abstracts which haveto be prepared.I n many cases the papers in the physiological orbiochemical journals deal almost exclusively with the pure chemistryof substances occurring in living organisms, and have comparativelylittle bearing at present on biological questions. I n other cases, theresearches are continuations of work previously undertaken, or theworking out of details in what were before unfinished investigations.Under this head we may place the greater part of Abderhalden'swork, in which new analyses of the various kinds of silk, and otherproteins, or the detection of peptolytic enzymes in the tissues byhis optical method amplify previous researches. I n the same way,E. S. London and his colleagues have published numerous additionsto their prolonged series of papers on the phenomena of and thelaws regulating digestion and absorption. London and Abderhaldenrun each other very close in the volume of their output. Thechemistry of colloids is another fruitful and favourite line ofresearch. Frankel, Thierfelder, Rosenheim and Tebb, and othersare still working and publishing papers on the chemistry of thatinteresting group of substances known as the lipoids ; this subjectformed the basis of a very keen debate a t the Vienna Congress, themain difference of opinion being the relative importance of thesesubstances in biological processes.Another spirited discussion alsooccurred on the same afternoon as to whether choline produces ar i s e or it fall of blood pressure.Modrakowski still maintains, inopposition to all other workers, that it is a pressor substance.4 Theold question as to whether pepsin and rennin are distinct enzymesor not still continues in an unsettled state.6 Nuclein and purinemetabolism is recognised now as one of the most important of thequestions confronting physiologists, and Schittenhelm, Bang,W. Jones, Mendel, Mare& and others are still applying themselvesto it.6 Another interesting series of papers relates to the formation4 See for instance, Abderhalden and F. Muller, Zeitsck. physiol. Chent., 1910, 65,420 ; A., ii, 530 ; Med. Klinik, 1910, No. 22 ; A., ii, 725 j F. Muller, PJEuger'sArchiv, 1910, 134, 289 ; A , , ii, 881 ; Mendel and Underhill, Zentr. Physiol., 1910,2% 251 ; A., ii, 735.5 See, for instance, W.Sawitsch, Zeitsch. physiol. Chem., 1910, 68, 12 ; A.,ii, 876 ; Funk and Niemann, ibid., 263 ; A., i, 801 ; Rakoczy, ibid., 421 ; A . ,i, 801.6 Some of the most important of these papers are the following : Schittenhelniand others, Zeitsch. physiol. Chem., 1909, 63, 248 ; A., ii, 52 ; Wells, J. BioZ.Chem., 1910, 7, 171 ; A., ii, 322 ; Schittenhelm and Seisser, Zeitsch. expt. Path.Ther., 1909, 7, 116 A., ii, 423; I?. Sauerland, Zeitsch. physiol. Chem., 1910, @,16 ; A., i, 345; W. Jones, ibid., 65, 383 ; A., ii, 526 ; Scaffidi, Biochenz., Zcitsch.,1910, 25, 296 ; A., ii, 626 ; Schittenhelm, Zeitsch. physiol. Chem., 1920, 66, 53 ;A., ii, 625 ; Wiechowski, Biochem. Zeitsch., 1910, 25, 431 ; A., ii, 634 ; Masing,Zeitsch.physiol. Chem., 1910, 66, 262 ; A., ii, 631 ; Vogtlin and Jones, ibid., 250 PHYSIOLOGICAL CHEMISTRY. 189of the acetone group of substances, of which perhaps the mostimportant is that by Dakin, in which he shows that not only isthe liver capable, by means of an enzyme, of transforming aceto-acetic acid into 0-hydroxybutyric acid, but is also able, by means ofanother enzyme, of accomplishing the reverse change.’More papers on the metabolism of creat.ine and creatinine wereinevitable after the new views on the subject put forward byMellanby and others made their appearance; but the points indispute do not seem nearer settlement, except that all observers arepretty well agreed that the liver is the main seat of the change;another burden is thus added to the duties of this uncomplainingorgan, and the new duties have been accumulating with greatrapidity during recent years. Blood coagulation has not yielded theusual quota of papers this year, the only one of importance being byHowell,8 who confirms the view already expressed by Rettger, work-ing in his laboratory, that thrombin is not an enzyme. Amongst theother familiar titles I will allude to one more only, namely, thecomposition of the Bence-Jones protein.Both Rosenbloom andWilliams 10 have brought forward some striking evidence in favourof an entirely new view of its nature; hitherto it has been lookedupon as a rather unusual form of proteose; there now seems goodground for the belief that it is related to the mucoid found in osseoustissues; if this is so, the relation between bone disease and itsappearance in the urine is intelligible.I have thus passed in rapid review a few of the most importantgroups of researches that have been published, and I do not proposet o treat any of these at greater length; many of them have beenthe subject of fuller description in former volumes of these reports.The topics I intend to select for more extended notice this year are,first, the physiology of respiration, which has had new light thrownupon it during the year by some very important investigations; andsecondly, a series of pathological problems, such as the Wassermannreaction, anaphylaxis, the chemistry of cancer, sleeping sickness,and possibly one or two others.d., ii, 631 ; Bang, Biochem.Zeitsch., 1910, 26, 293 ; A., i, 647 ; Hirokaws, ibid,441 ; A., ii, 787 ; Steudel and Brigl, Zeitsch. phyysiol. Chem., 1910, 68, 40 ; A . ,i, 703 ; Ackroyd, Bw.-Chem. J., 1910, 5, 217 ; A., ii, 977 ; Mendel and Lyman,J. BWZ. Chem., 1910, 8, 116 ; A., ii, 973 ; I?. Mare;, PJiiger’s Archiv, 1910, 134,69 ; A . , ii, 973.J. Amel= Med. Assoc., 1910, 54, 1441 ; A., ii, 632 ; J. Biol. Chin., 1910, 8,97, 105 ; A., ii, 976, 977. * dmer. J. Physiol., 1910, 26, 453 ; A., i, 793.Proe. Amer. SOC. Biol. Chemists, 1909 ; J. Biol. Chem., 1910, 7, xiv ; A., ii, 731.lo Bw-Chem. J., 1910, 5,225:; A., ii, 981. Another view on the Bence-Jones proteins advanced by Christiaens and others (J. Phurm. Chim., 1910, [vii], 1, 582 ; A.,ii, 733) that the reaction is not specific, but is given by several members of theprotein group190 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.R es pka t ion.It is almost a truism to assert that the progress of knowledgemainly depends on the invention of new experimental methods, orthe perfection of old ones.Science owes a great deal to thereasoning power of the thinker, and to the acumen of the guesser,but both are alike futile until facts are accurately determined. Theimprovements of the microscope and of microscopic technique lieat the basis of our present knowledge of structure; the perfectionof the calorimeter has enabled workers to state with certainty thatthe law of the conservation of energy applies to the living organism;the various instruments which enable one to analyse gases both inthe air and in the blood have done much to lay the foundations ofour knowledge of the respiratory process.There was, however, oneinstrument which has always been regarded with suspicion, andthat was the aerotonometer in its various forms. The object of thisinstrument is the determination of the tension of the blood-gases ;and it was just this doubtfulness in the accuracy of its readings thatallowed theorisers a chance of advocating rival views on themechanism of the gaseous exchange which occurs in the lungs, andis usually spoken of as external respiration. Physiologists werethus divided into two camps; one party consisted of those whofollowed Pfluger in believing that oxygen entered and carbondioxide left the blood in obedience to the physical laws of diffusion;and the other party, led by Bohr, of Copenhagen, and Haldane, inthis country, maintained what is usually called the vitalistic orsecretory view.These observers believed that the cells which line thepulmonary air sacs have the power of piling oxygen into the bloodfrom the alveolar air until its tension in the blood was higher thanit is in the air, and in the same way thought that the same cellshad the corresponding power of secreting the carbon dioxide in theopposite direction. Text-books on physiology use many pages indiscussing the pros and cons of the two theories, and finish byleaving the unfortunate learner in a chaotic state of mind. I n t%hefuture, such a discussion will be no longer necessary; the questionhas been finally settled, and this mainly by the invention of a newand accurate aerotonometer.The inventor is August Krogh, andhe and his wife have published their work in a most interesting andilluminating series of papers.ll Their work vindicates and provesup to the hilt the mechanical theory, and is all the more strikingas they started their investigations with a bias in favour of thevitalistic view, and issued their papers from Bohr’s laboratory, itsbirthplace.8kand. Awh. Physiol., 1910, 23, 179, 193, 200, 217, 224, 236, 248 ; A . ,ii, 512PHYSIOLOGICAL CHEMISTRY. 191Haldane’s later experiments in reference to carbon dioxide hadled him implicitly to abandon the secretory theory in relation tothat gas, for the immediate effect on the respiratory centre ofchanges in the alveolar tension of carbon dioxide could not beexplained except on a physical hypothesis.It is satisfactory to beable to chronicle that since Krogh’s work has been published, hehas admitted the validity of Krogh’s criticisms on his method, andhe finds on repeating his experiments that diffusion alone will alsoexplain the entrance of oxygen into the blood.l2 He, however, stillhas a lingering belief that. the secretory process is necessary as asupplementary process under certain abnormal conditions.The aerotonometer, which has made possible this satisfactory stat0of things, is quite a simple one. I n the instruments previouslyused, the blood was brought into contact with a considerable volumeof the gas.In Krogh’s apparatus, the volume of the gas is small,consisting only of a bubble, and this is completely surrounded withthe blood; it can then be withdrawn into a capillary tube, andmeasurements of the increase or decrease of its size made withaccuracy.I n view of the fact that I have already given full abstracts ofKrogh’s work, it will be unnecessary again to recapitulate all thesteps in his methods and arguments. Those interested in the subjectshould not neglect to read them in the original. I shall thereforebe content with noting how small is the tension difference whichis necessary to determine the passage of the gases across the inter-vening membrane. The thinness of its cells is highly favourable todiffusion of gases, and they are not adapted for secretory work;in this they contrast very forcibly with the cells found lining organs,such as the swim-bladder of fishes, where secretion of oxygen doesoccur.Indeed, in birds the alveolar epithelium is absent, and theendothelial cells of the capillaries alone have to be traversed bythe gases.External respiration, interesting though it is, is, after all, only ameans to an end; that end is the utilisation of oxygen in thetissues; the using up of oxygen in the tissues, and the-productionthere of carbon dioxide constitutes what we call tissue or internalrespiration. The oxygen is transported in one direction, and thewaste carbon dioxide in t,he opposite direction by the flowing blood.One gram of kmoglobin combines with a definite amount of oxygen(1.34 c.c.), and is practically saturated at the atmospheric pressureof oxygen (one-fifth of 760 mm.); if placed in an air pump, theoxyhzmoglobin parts from its load of oxygen at first very slowly, andeven at half the normal pressure the haemoglobin is still nearlyl2 Haldane and Douglas, Proc.Xoy. SOC., 1910, B, 82, 331 ; A., ii, 511192 ANNUAL REPOBTS ON THE PROGRESS OF CHEMISTRY.saturated; below this, the loss is somewhat more rapid, and in avacuum all the oxygen is dissociated. The due supply of oxygenis thus kept up to practical saturation of the haemoglobin at thealveolar tension of oxygen, which is not much below one-fifth of anatmosphere. I n order, however, that the tissues may readily gettheir oxygen, it is not only necessary that the hzemoglobin shouldobtain its full supply under the ordinary atmospheric conditions,but there is another sine qua %on-the hkmoglobin must readily partwith its oxygen under the pressure conditions which prevail in thetissues; the oxygen must come off from the hzemoglobin first intothe blood plasma, in which fluid the fall of oxygen tension is notnearly so great as in the vacuum of an air-pump.I n round figures,1 C.C. of arterial blood contains 0.2 C.C. of oxygen, and the venousblood half this amount. What are the factors in the blood, whichare absent in a pure solution of oxyhzmoglobin, which enable it togive up half of its oxygen in the mere fraction of time, a t most onesecond, that it occupies in travelling along the capillary vessels?There are three main circumstances that play a part in assistingthe ready dissociation of oxyhaemoglobin; the first of these is thepresence of carbon dioxide, and the importance of this factor wasfirst shown by Bohr 13; how the carbon dioxide acts is not known,for carbon dioxide does not, like carbon monoxide, possess the powerof replacing the oxygen of oxyhzemoglobin; it is an undoubted factall the same, and can be demonstrated by a very simple experiment;if one takes two closed tubes of defibrinated blood, both exposed tothe same tension of oxygen, and to one is added ,a little carbondioxide, the presence of the latter renders the blood obviously morevenous in tint.The second factor is the high temperature of the body, and thedet'ails of this factor have been worked out by Barcroft and King.14In muscular exercise with its accompanying rise of temperature, infever, and in inflammation, the organism or part of it requiresoxygen at a more rapid rate than usual; the rise of body tem-perature enables the blood to meet this demand.The third factor is that other acids may take the place of or assistcarbonic acid in turning out the oxygen; the only acid which hasbeen specially investigated in this relationship is lactic acid; andits importance came into evidence in recent work on respiration atgreat altJtudes 15; here not only is the rise of body temperaturefavourable to respiration, but the acidosis which also occurs isSee also a recent paper by Mnnchot, Annnlen, 1909, 370, 241 ; A., ii, 137.Caspari and Lcewy, Biochem.Zeitsch., 1910, 27, 405 ; A . , ii, 969 ; see alsol4 J. Physiol., 1909, 39, 374 ; A., ii, 50.Barcroft and Orbeli, J. Physiol., 1910, 41, 355PHYSIOLOGICAL CHEMISTHY. 193another effort of nature to compensate for alterations in atmospl~ericconditions.The study of hhe details of tissue respiration as a measure ofactivity in different organs has also progressed during the last twelvemonths, and I propose to conclude this section of my report’ byreferring to a few in which I consider the results are of specialinterest.The first of these which I will take is the investigation of themetabolism of the surviving warm-blooded heart by E.Rohde.lGHe confirmed many points in relation to the isolat.ed mammalianheart which ha.d been established by previous investigators, forinstance, that of Locke and Rosenheim on its capacity to utilisesugar, and of Barcroft and Dixon on its gaseous metabolism. Thespecial feature of Rohde’s apparatus (the demonstration of whichgreatly interested those who attended the Vienna Congress ofPhysiologists) is that simultaneously with the study of metabolism,it is possible to measure the work of the heart. The metabolidchanges are found to run parallel to the amount of work done. Inthe presence of sugar, not only is the sugar burnt, but other con-stituents in the heart itself (reserve material) are burnt also, andthis leads to the production of carbon dioxide.When sugar andother nutritive material are not supplied in the perfusing fluid;these reserve materials are alone utilisable ; these probably originatefrom fat and protein, and the hypothesis is put forward that thdheart forms a sort of internal secretion, in which glycolysis occurs.This last conclusion must bs accepted with reserve; the chief valueof the research is that accurate data are available to support thethesis that gaseous metabolism is a memure of physiological work,a conclusion which we shall be using in an argument a few para-graphs ahead.Brodieand his colleagues17 have shown that the work of absorption ofsaline and protein material is accompanied with an increased gaseousmetabolism. The intestine, as is well known, consists mainly of twosorts of tissue, muscular and epithelial or cellular.It has beenpreviously shown that, weight for weight, glandular tissue uses moreoxygen and gives out more carbon dioxide than muscular tissuedoes. Muscle doubtless contributes more to the production ofanimal heat than glands do, but this is because of its bulk, notbecause of the intensity of the respiratory process. I n the intestinethe same rule prevails; the cellular elements concerned in absorp-tion are mainly responsible for the increase in the gaseous exchanges.The second organ I will select for mention is the intestine.18 Zeitsch. phyciol. Cltem., 1910, 68, 181 ; A . , ii, 976.l 7 J. PIiysioZ., 1910, 40, 135, 173 ; A , , ii, 518.REP.-VOL. 1’11. 194 ANNUAL REPORTS ON THE PROQRESS OF CHEMISTRY,0. Cohnheim,ls who has also taken up the same organ as an objectof study, has been mainly concerned with the gaseous metabolismof the muscular coat of the intestine and stomach.It is satis-factory to be able to state that, although the methods employed inthese two series of researches are different,, the figures obtained arein substantial agreement. I may take the figures for the organ atrest, and compare them. The amonnts of carbon dioxide in C.C.produced per gram per minute are as follows:1. In intestinal muscle . . . ... .. . . .. ... 0.0071 (Cohnheim).2. In intestinal mucous membrane.. 0.0318 (Brodie).3. In small intestine as 3 whole ...... 0 02 (Brodie).4. 1 , Y7 ,, ...... 0.023 (deduced Iioin a combinationof the two sets of figures).These figures, roughly speaking, are doubled during digestivework.The importance of a consideration of figures such as thesedoes not depend on their absolute values, although, of course, it isalways more satisfactory to have accurate figures than roughvaluations; they show that the alimentary tract is a factor to bereckoned with in any considerations of the total metabolism of thebody, and support the view taken by Zuntz, a view which has beenthe subject of much controversy, that the work of the digestive tractin actual digestion and absorption is not a negligible consideration.19A third instance of the value of the gaseous-metabolism method inascertaining the physiological meaning of important processes in thebody we owe to the work of Barcroft and Straub 2o on diuretics.Wemay assume as true that physiological work cannot occur withoutincreased gaseous metabolism, and, conversely, that an increase ofsuch metabolism is a sure proof of physiological activity, as we havealready stated in our discussion on cardiac metabolism. If that isso, then if a diuretic produces an increased flow of urine withoutany increase of gaseous metabolism, it must have produced thisresult by mechanical means, and not as a result of increased actionof the secretory apparatus of the renal cells; this is actually so inthe case of certain diuretics, and so Barcroft and Straub havebrought forward a piece of most valuable evidence in the elucidationI8 Cohnheim and Pletneff (Zeitsch.ph,ysiol. Chem., 1910, 69, 89, 96, 102, 106 ;A., ii, 1079) have used quite different methods froin those employed by Brodie;their apparatus is a small one constructed on the principle of the Atwater-Benedictmachine. In this relationship, one should also refer to Thunberg’s micro-respirometer, which has done good service ; for rccent work on gaseous exchanges infrog’s muscle with this instrument, see Thunberg, Skand. Arch. Physiol., 1909, 22,406, 420 ; A., ii, 54.l9 Recent papers in support of Zuntz’s view which should be COI sulted are by0. Miiller, Biochcm. Zeitsch., 1910, 28, 437, and H. Dahm, ibid., 456; A,, ii, 1083,2o J. Physio/., 1910, 41, 145 ; A., ii, 1090PHY SIOLOGlCAl, CBEMJSTRY. 195of the vexed problem whether urine formation can ever be purelymechanical.The diuretics they studied fall into two groups: (1) those whichproduce urine without alteration in the gaseous exchange of thekidney (Ringer’s solution, and sodium chloride in hyper- and hypo-tonic solutions) ; (2) those which cause increased gaseous exchange(urea, caffeine, sodium sulphate, phloridzin).I n the case of ureaand caffeine, there is a definite poisoning action, as shown by sub-sequent depression of the gaseous exchange. The distinctivefeatures of the urine produced by the second class are attained bya process of secretion on the part of the tubules, and not by aprocess of reabsorption. After poisoning the cells by corrosivesublimate or by the diuretics of the second class, a flow of urine canstill be produced by the first class of diuretics; the urine so producedappears to be isotonic with the blood-serum.The special interestof the research is the action of diuretics of the first class, and theseproduce urine independently of secretory activity (as judged by theabsence of increased metabolism), and so their action must beattributed to mechanical filtration. The proteins of the bloodplasma, in virtue of their osmotic pressure, would attract water intothe blood; the capillary pressure would drive water into the urine.Suppose, for instance, that the capillary pressure is equal to 27 mm.of mercury, and that the osmotic pressure of the proteins is a littlelower, say 25, as it probably is in normal circumstances, then theI f the amountof protein in the blood plssma were reduced to half, theosmotic pressure will be reduced to 12.5, and the available filteringpressure is then 14.5, a sevenfold increase, and diuresis will occur.This argument was justified by testing it as follows.The animalwas bled very considerably, and the blood replaced by Ringer’ssolution, containing blood corpuscles in suspension ; the diuresis soproduced was very considerable, although the blood-pressure wasvery low; and this was attended with no increase in the gaseousexchange.Having now discussed this most important physiological subject,I pass now to the consideration of the pathological topics, as outlinedin the introductory portion of this report.No doubt many chemists, seeing papers with such titles asanaphylaxis or the Wassermann reaction, will put them aside, simplybecause the terms employed are foreign to them.The subjectsreally, if they were not concealed by the jargon of the specialist, areof the deepest interest, and I hope to be able to explain in languagei ~ 9 free from technicalities as possible, and without entering intofull details, the meaning of the work in question,vailable pressure for filtration would be 2 mm.0 196 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,The Wassermann Reaction.It is well known that the injection of a toxin into an animal leadsto the production of an antitoxin ; that the injection of foreign bloodcorpuscles into the blood stream leads to the development in theblood of the animal which has received the injection of a substance(hzmolysin) which is capable of dissolving the foreign corpuscles ;that the injection of it foreign protein leads to the development ofa substance in the blood capable of causing a precipitation of thatprotein.These examples serve to illustrate the general truth whichunderlies modern work on immunity and allied problems. Immunitydue t o the development of an antidote in the body appears to belimited almost entirely to poisons of protein-like nature; thetolerance which is exhibited towards such drugs as arsenic, oralkaloids, or comparatively simple materials, such as adrenaline, isprobably in quite another category of events. The genera1 term nowadopted for toxins, etc., which are capable of inducing the organismto meet the attack by the production of an antidote is that ofantigen.Wassermann founded his celebrated biological test for syphilis uponthe theory of antigen and anti-substance, and although he was herepossibly wrong, yet the test is now recognised as most trustworthyas an empirical one. The original method is a little more tediousand difficult of application than the modifications of it which havesince been proposed, but most authorities are agreed that the originalmethod is more certain in its results.The reaction (omitting detailsin technique) is performed in the following wavy. A rabbit isimmunised against the blood of the ox, that is to say, several dosesof washed ox corpuscles are injected into the ra.bbit.The serumobtained from the blood of the rabbit has then the power of dis-solving the red corpuscles of ox blood. This, according t o t.heEhrlich doctrine, is owing to the presence in the serum of twosubstances, one an enzyme-like material called the complement, andthe other named the amboceptor, which anchors the complement onto the corpuscles, the object of its attack. The complement is notspecific, but is found in the serum of normal animals also; theamboceptor is specific; it is the special key necessary to fit theox corpuscle. Corpuscles of other animals would cause the develop-ment of other special keys, or specific amboceptors. There isstill another difference between the complement and the amboceptor,and this property enables the investigator to separate them; t,hethe complement is thermolabile, and is destroyed by heating theserum to 5 6 O for thirty minutes; the amboceptor is thermostable,and is not affected by this treatment.The rabbit’s serum so heatePHYSIOLOGICAL CHEMISTRY. 197is therefore no longer capable of dissolving ox corpuscles. But ifthe mixture of heated rabbit’s serum and ox corpuscles receives anaddition of some normal guinea-pig’s serum, this supplies the com-plement, and the ox corpuscles are dissolved.The next step is the preparation of an aqueous or alcoholic extractof a syphilitic liver (usually obtained from a foctus), and thecollection of a certain amount of serum or cerebrespinal fluid fromthe patient suspected of suffering from syphilis.The suspectedserum, the extract of syphilitic liver, and a small amount of guinea-pig’s serum are then mixed together, and the mixture suitablydiluted with saline solution. A series of tubes containing thismixture are then placed in an incubator at 3 7 O for one hour, andt h e ox corpuscles previously sensitised by the addition of the heatcclrabbit’s serum are then added.. The tubes are returned to theincubator for two hours, and then put on ice overnight. The nextmorning the amount of hEemolysis is observed. A control experi-ment using normal human serum or cerebro-spinal fluid should bemade at the same time; in the control, hzemolysis will, of course,occur. But if the patient is suffering from syphilis, no hEmolysiswill take place, and the blood corpuscles will simply have sunk andformed a deposit at the bottom of the tube.This is because thesyphilitic serum or cerebro-spinal fluid has combined with thecomplement of the guinea-pig serum, and this I f fixation of thecomplement ” has prevented hzemolysis.The abandonment of the antigen-anti-substance theory as anexplanation of the reaction has followed upon the discovery thatextracts of guinea-pig’s heart, human heart, soaps, and lecithin mayreplace the extract of syphilitic liver in the method.21 But what-ever be the true explanation, the reaction is universally acceptedas a most trustworthy aid to diagnosis, although it is perhaps mostdefinite when the extract of syphilitic liver is employed.Sachs and Rondorie pointed out that the manner of dilution withsaline solution makes a difference.If the dilution is performedrapidly, the mixture becomes densely opalescent ; this can to a largeextent be obviated by performing the dilution drop by drop. Theopa.lescence interferes with the power to fix complement, and theseobservers explain this as a physical result of the size of the particlesin suspension. The main result of these workers has been confirmedby Gatz and Inaba,22 who find the reaction sharper with mixturesthat have been diluted slowly, although they doubt whether thephysical explanation is the correct one.I n relation to the chemistry of the Wassermann reaction, but little21 See, for instance, Browning and others, Biochem. Zeeitsch., 1910, 25, 8 5 ; A ., ii,629.lbid., 1910, 28, 374 ; A . , ii, 1093198 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.is at present known. Mott23 finds that a fluid giving the reactionfails to do so after the removal of the proteins; Sachs24 thinks thesubstance is a globulin ; and Noguchi 25 has come t o the conclusionthat it is attached to the euglobulin, from which it cannot beseparated by solvents. As to how this arises in the cerebro-spinalfluid, several suggestions have been offered, one being that it is atransudation from the blood; if it were so, one would expect to findthe reaction given in cerebral syphilis, but as a rule the cerebrespinal fluid does not give the reaction in this disease, although theblood-serum does. It is now pretty well proved that the cerebro-spinal fluid is secreted by the epithelium which covers the choroidplexus,26 and so Mott was led to make a comparative examinationof this structure in general paralysis and other diseases, and foundthat although the choroid plexus in general paralysis, as comparedwith other diseases in patients of the same age, showed more fre-quently cystic degeneration and denudation of the choroidalepithelium, still he was unable to associate the two facts.27 Anothersuggestion has been made that the substance responsible for theWassermann reaction has its origin in the increased number oflymphocytes in the fluid.Lymphocytosis is frequently present bothin cerebral syphilis and genera.1 paralysis, but in the former diseaseit may be present, and yet the Wassermann reaction be negative.The mention of these two diseases side by side needs a word ofexplanation to the non-medical reader.Syphilis is a disease which is most widespread in its effects, andin its later stages is accompanied with growths (gummata,) andinflammatory conditions in different organs.Among these organsthe brain and the spinal cord must be reckoned, and disease hereproduces most serious results. Nevertheless, syphilis even at thisstage is curable, for instance, by mercurial inunction.After an attack of syphilis has occurred and is cured, the patientis even then threatened with an even more serious danger. He isliable to certain degenerative diseases of the central nervous system,of which locomotor ataxy (tabes dorsalis) and general paralysis of the23 F.W. Mott. Oliver-Sharpey Lectures on the Cerebro-spinal Fluid, RoyalI am greatly indebted College of Physicians, London, Lancet, July 2 and 9, 1910.to these lectures for much which appears in the present section of this report.24 Quoted by Mott.2i Ibid.26 W. E. Dixon and Halliburton have shown that an extract of choroid plexus, orchoroid gland as it may be called, causes when intravenously injected an abundantflow of cerehro-spinal fluid (Proc. physiol. Soc., 1910, xxx ; J. PhpioZ., 40 ; A., ii,522).27 Dixoii and Halliburton found that extracts of the choroid plexuses from casesof general paralysis were equally active i n promoting the flow of cerebro-spinal fluidas extracts of those from normal men and animalsPHYSIOLOGICAL CHEMISTRY.199insane are the most frequent. Such a. condition it is now usual tospeak of as para-syphilis. The greater seriousness of para-syphilisis due t o the fact that it is, with our present knowledge, not curable.It not infrequently happens that the symptoms of syphilis andparaayphilis are very much alike, and here comes in the usefulnessof the Wassermann reaction. I n both classes of disease, the blood-serum gives the reaction, but the cerebro-spinal fluid only gives it,as a rule, in general paralysis and other para-syphilitic affections.Looked at from the patient’s point of view, it is worth his sacrificinga small amount of his blood or cerebro-spinal fluid in order that hismedical attendant may determine which type of disease he has todeal with; and if the Wassermann reaction is negative in thecerebro-spinal fluid, he has the satisfaction of knowing that he mayexpect to be restored to health.Sleeping Sickness.Chemists who have cultivated the habit of reading or even ofglancing through the literature of sciences outside their own cannothave failed to notice how largely the tropical disease, known assleeping sickness, or African lethargy, has occupied the attention ofmedical workers during the past few years.The publications of theRoyal Society on the subject are now very numerous. Pharma-cological journals devote much space to a consideration of the drugsproposed to cure the disease, and this is reflected month by monthin the abstracts of our own Journal. Syphilis is obviously animportant subject with a far-reaching effect on the well-being ofthe race, and from the Imperial point of view, diseases apt toattack our fellow-subjects in Africa, India, and other places withinor near the tropics cannot fail to interest the patriotic Englishman.The Commissions which have been sent out to investigate sleepingsickness have fully justified their existence, for under the leadershipof Bruce they have succeeded in demonstrating what is the causeof this mysterious malady which decimated the inhabitants of pre-viously well-populated and prosperous districts od Africa. Thedisease is caused by a minute animal parasite called a trypanosome,and is infectious because the parasite is carried from one animal orone person to another by means of certain biting flies of the tsetse flytype.If the flies are exterminated, or precautions taken to avoidtheir bites, the disease can be prevented, and already great progresshad been made in this direction. Just as there are different kinds ofbacteria, so also varieties of the trypanosome exist, and these producedifferent symptoms, or have an especial liking for certain species ofanimals. The general term of all these diseases is trypanosomiasis.I n promoting the beneficent results that have already followed th200 ANPU’UAT, REPORTS ON THE PROGRESS OF CHEMISTRY.discovery of the cause of these maladies, the chemist has playedlittle or no part; that we owe to army surgeons, bacteriologists, andzoologists.The work of the chemist and the pharmacologist hascome in at another place. It is small comfort to the patient alreadyinfected to know that zoologists are studying the habits of the flies,and so trying to prevent other people from being bitten. He wantsto be cured. Atoxyl and similar preparations and compounds ofarsenic and antimony have been the substances found most beneficialin this direction, and hardly a month passes but what one will findin our pages summaries of elaborate investigations of the chemicalnature of these drugs, of fresh compounds prepared likely to be lesstoxic, or of experimental work on animals and men in the testingof the preparations. I wish it were possible to record that theirefforts had been attended with complete success; the success hasbeen partial, and mainly confined to the cure.of trypanosomiasis inanimals; but such as i t is, it bodes well for the future. The nameatoxyl was originally given to the mmt widely employed drug ofthis class, on the supposition that it was not poisonous to man,though fatal to the trypanosome. The name has been shown to bea misnomer. One has here again the old difficulty of finding some-thing that will kill the parasite without doipg harm to the host inwhich the parasite dwells. As I have indicated, however, this searchis by no means hopeless. I have been led into this passing allusionto the subject of sleeping sickness from a consideration of certainaspects of syphilis, for it is now recognised that the latter diseaseis due to a spirochzte, an organism not unlike the trypanosome, andalready some work has been performed in i%e treatment of syphilison the lines of the treatment of trypanosomiasis.2* It is at presenttoo early to state definitely whether goqd results have accrued, butthose who have employed Ehrlich’s new arsenical preparation,diaminodihydroxyarsenobenzene, now familiarly known in qurrentmedical literature as ‘‘ 606,” are most enthusiastic.A recent pa.per,for instance, by McIntosh and Filde~,2~ concludes with the followingparagraph :“The importance of ( 6 0 6 ’ as a destroyer of spirochaetes cannotbe over-estimated, even apart from the beneficial effect upon thepatient. I n those cases in which spirochaetes were demonstrablein very large numbers before inoculation, none were found in lessthan twenty-four hours later, even after prolonged search.Thisfact has been already fully established. The importance of theobservation lies in the probability that cases of syphilis can berendered practically non-infective in a day or two. I f this be tlrue,Ehrlich will have swept away the scourge of 2000 yea-rs, and given2R See, for instance, F. Blumenthal, Biochcnz. Zcitsch., 1910, 28, 91 ; A . , ii, 982,Lnncct, 1910, ii, 1684PHYSIOLOGICAL CHEM I WRY. 201into the hands of any State which will avail itself of it a weaponfor the forcible suppression of syphilis.”It is only right, to state, however, that this optimistic view is notshared by all, and the medical journals will be found to containstatements in a diametrically opposite strain.A naph y laxis.A recently published lecture on anaphylaxis30 is followed by abibliography of the subject, containing 184 references.This wasin December, 1908. The list of papers might a t the present timebe easily doubled, for Zentralblatter, which deal with such matters,publish abstracts a t the rate of about twenty per month. This isjust an indication of the large amount of work centring aroundthis important piece of borderland chemistry. The word anaphylaxisdates from 1905, and was coined by C. Richet; he was studying theactions of two poisons obtained from sea anemones, which he namedcongestin and thalassin, and he found that if a small dose whichcaused no symptoms in a dog was followed twenty-two days laterby another small dose, the animal became ill and usually died.This increased susceptibility took a few weeks to develop, and lasteda considerable time, and the condition of hypersusceptibility orsupersensitiveness was named anaphylaxis (ana against, phylaxisprotection). The word implies something opposed to prophylaxis,but the phenomenon is not always harmful; it may be of distinctadvantage to the organism. The publication of Richet’s workled others to discover that the sea anemone’s poisons are not theonly ones which can produce the phenomenon, but that otherantigens (proteins, toxins, animal serums, and the like) may causeit also.At first sight, the anaphylactic state appears distinctlyharmful, and no doubt it is one of the dangers of serum therapy.When, however, a danger is recognised, it is possible to avoid it;in the early days of serum treatment, when the production ofimmunity was its only known effect, one can hardly doubt that if asecond dose was given during the anaphylactic state, severe illnessor even death followed; and there are on record cases of suddendeath produced in this way.Now that anaphylaxis is a matter ofcommon knowledge, unfortunate mishaps of this kind ought not t oocour.The phenomenon wits really known before Richet gave it itsname. For instance, in the case of vaccination, the reaction appearsafter an incubation of four days. I n a second vaccination, thisperiod is shortened, and the increased power of the organism toThe Harvey Lectnres, New York,1910.By John F.Anderson and N, J , Rosenau202 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.react is protective, and the anaphylaxis is in this case prophylacticand beneficial. The tuberculin and ma.l?ein reactions are well-knowninstances of anaphylaxis; these substances are not toxic to healthyindividuals, but the tuberculous patient is anaphylactic to tuber-culin, and the horse suffering from glanders to mallein. Thehypersusceptibility of some people to pollen (hay fever) is anotherexample.Anaphylaxis has, however, mainly been studied by the injectionof serum and foreign proteins into the guinea-pig, the animal usuallyselected for the purpose. Luckily, from the point of view of thera-peutics, horse serum is a comparatively harmless substance, whetherit is derived from a normal animal, or from a horse immunised againstdiphtheria; but a second injection during the anaphylactic state,even when used in small amounts, will possibly be fatal.The mostremarkable fact in this relation is the smallness of the dose necessaryto produce the exaggerated sensitiveness. A millionth part of a C.C.of horse serum will sometimes be sufficient to produce the effect ona guinea-pig, and 0~000,000,05 gram of egg-white has been statedto be enough. It also requires very small amounts when given ina second injectlion to produce poisonous symptoms; 0.1 C.C. injectedinto the peritoneal cavity may cause death, whilst much smalleramounts injected direct into the circulation or into the brain will befatal.I n the face of such small figures, i t seems almost hopeless toattempt a chemical explanation of the phenomenon, or t o isolatethe poisonous principle. The hypersensitive state may further betransmitted by the female guinea-pig to her progeny.The experiment in which the animal receives its second dose is avery striking one; death usually is a matter of minutes only; theblood pressure falls enormously, the abdominal viscera are gorgedwith blood, and hanorrhages are frequent ; the bronchial musclesare acutely contracted. J. Auer 31 sensitised guinea-pigs by thesubcutaneous injection of 1 to 2 C.C. of horse serum; the maximumsensitiveness was reached about the ninth week, and this was main-tained for at least twenty-three weeks more, the longest intervaltested.Noting the prominence of bronchial constriction among thesymptoms, atropine was used as an antidote, and was found to beof distinct utility; without atropine the death rake was 75, withit only 28 per cent. The view taken by most observers is that thepoison acts in this animal upon the respiratory centre.Numerous theories have naturally been suggested to explain allthese remarkable facts; it is a good general rule that whenhypotheses are many, the correct explanation has still to be found.It. would be impossible to state them all in t,his brief summary;31 Amer. J. Physiol., 1910, 26, 439 ; A,, ii, 985PHYSIOLOGICAL CHEMISTRY. 203I propose to take one or two as samples.The first selected is thatof Gay and Southard.32 They consider that there is in the seruma substance provisionally termed anaphylactin, which is not absorbedby the guinea-pig’s tissues, is not neutralised, and is excreted withgreat slowness; it therefore remains as a constant irritant t o thecells of the body, so that their reactivity for the other constituentsof the foreign serum is increased, I f then the cells are suddenlypresented with a second dose of the serum, they are overwhelmed inthe exercise of their increased assimilating functions to such a degreethat local or general death may occur.As is usual in such theorising, it has been found necessary toinvent a series of new words; for example, sensibilisinoghne, sensi-bilisine, and antisensibilisine ; these figure in Besredka’s theory, butin the present state of uncertainty it is not necessary to explain thesemore fully.Rosenau and Anderson’s work has shown that’ anapliylaxis isspecific, for guinea-pigs may be sensitised to three substances at thesame time (milk, serum, and egg-white), and subsequently react toa second injection of each one of these substances, acting as thoughit was susceptible to three separate infectious diseases.This dis-covery indicates tha.t chemical changes rather than morphologicalalterations are at the basis of the phenomenon, and complicatesmatters by the assumption that many anaphylactins exist.Richet, who has followed up his work on the poisons of actinia:with further experiments on other toxins (for example, one extractedfrom the mussel), thinks that anaphylaxis is due t’o the presence ofa toxigenic substance not poisonous in itself, but capable of pro-ducing poison by reacting with the second injection of the extractor serum.I n support of this view, he points out that a mixture ofthe serum of a sensitised dog and of the mussel extract in vitro ismore toxic than the extract alone.Vaughan and Wheeler, in view of the circumstance thatanaphylaxis can be produced by proteins in a state of comparativepurity, believe that the phenomenon must be due to a toxic fragmentof the protein molecule.It is a little difficult for one like myseIf, who is only able to viewpathological questions through physiological spectacles, to appraisethe relative merit of the rival theories.It will probably be saferto make no such attempt here, but to be content to await furtherknowledge. The most recent paper I have read on the subject,however, appears to me to be of great value, and certainly throws anew light upon it. It is written by Dr. W. M. Scott 33; this investi-s2 J. Med. &smrch, 1907, 16, 143 : 1908, 18, 407 ; 1908, 19, 1, 5 , 17.J. Path. Bad., 1910, 15, 31204 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.gator has performed his experiments on the rabbit, and in thisanimal the symptoms are not so markedly bronchial as in theguinea-pig; the majority of the symptoms are due to the great fallof blood pressure, and this in its turn is attributed to the act,ivedilatation of the capillaries, which is accompanied by injury to thevitality of the cells of which they are composed.The main interest,however, of the paper occurs in connexion with the answer to thequestion, What modification has taken place in the economy of theanimal to lead to behaviour so vastly different from the normalanimal? The fact that the sensitive condition can be transferredt o another animal by the serum fixes attention on this fluid as con-taining the responsible factor. I n the serum the precipitin contentruns parallel with the severity of the symptoms, and at once suggeststhat the presence of this and not of any other hypothetical anti-substance (anaphylactin, sensibiline, etc.) is the new factor to whichis due the difference between the normal and the sensitive animal.Doerr and Russ 3* have noticed the same correspondence betweenprecipitin strength and lethality in the guine&pig. The dis-appearance of the precipitin from the serum after the anaphylacticcondition passes off is a point in favour of the same view,How the interaction of precipitin and antigen acts so as to producethe symptoms and morbid changes is still a matter for speculation.I n the now historic phrase, we must be content to (( Wait and see.”The Chemistry of Cancer.Cancer is a subject as important to the well-being of the race assyphilis, and so far as cure of this terrible scourge is concerned,medical men are as far off its ever they were.Those who work underthe auspices of the Imperial Cancer Research Fund are a little morehopeful in their reports than they were in previous years, but as;Sir Alfred Pearce Gould has recently pointed out, hope is ratherof the pious than of the practical kind.I have in previous issues ofthese Reports stated that in mice a certain fairly large proportionof spontaneous recoveries occur; in man, also, there is a very smallpercentage of cases which get well without operative interference.Nature therefore has the power to counteract the malady, and it isthis circumstance that makes the investigator less hopeless than hewas previously. I f nature’s mode of cure can only be discovered,there is hope for suffering humanity. It is a large “if,” but thatshould not hinder the progress of research.The reports of the Imperial Cancer Research Fund contain butlittle that the chemist can get hold o f ; the bacteriologists andparasitologists have had a long and fruitless innings, and it can34 Zcitsch.Immun. epp. Ther., 1910, 4, 706PHYSJOLOGICAL CHEMISTRY. 205hardly be doubted that chemistry will play a part in the ultimatesolution of the cancer mystery. This branch of work has not beenneglected by those who work outside the encl.osure of theImperial Cancer laboratories, but up to the present little that isdefinite has been discovered. That there are fundamental changesof a chemical nature in the organism of a cancer patient isundoubted ; the limitation or disappearance of the acid of the gastricjuice is not a mere local conditim of the mucous membrane.of thestomach, but an indication of a chemical state widespread through-out the body. It has also been proved beyond question that theblood serum in cases of cancer is very rich in antitrypsin. The mereestablishment of this fact has not been without practical importance ;a non-malignant tumour will often simulate cancer, and the investi-gation of the antitryptic power of the serum will do a great dealto settle the question; suppose it is found that there is no rise inthe antitryptic value, it is impossible to do more than imagine therelief which will be experienced by the patient; it is like a reprieveto a condemned man on the way to execution. Unfortunately, greathopes were built upon this discovery, which have never been fulfilled.Trypsin was vaunted at one time as a cancer-cure, and the dailyPress, encouraged by certain pseudo-scientific men of the samekidney, is greatly to be blamed for t.hus raising the hope of sufferers.I f a, few cases of cure can be adduced in support of this treatment,they are probably not more numerous than those of spontaneousrecovery just alluded to.Trypsin, after all, is only one of a largegroup of enzymes; many more remain t o be investigated, though atthe present stage of the inquiry it would be most unwise to pro-mulgate any theory of a connexion between enzyme-disturbance andthe occurrence of malignant disease, and still more unwise to preachthat cure lies in the direction of enzyme administration. The risein the antitryptic value of the serum is also not a specific character-istic of cancer; it is found, also, in obher pathological conditions;and in cancer and in these other pathological conditions one is quitein the dark a.s to whether this sign indicates a factor in the causeof the malady, or is one of its consequences, whether therefore theadministration of the enzyme will be favourable or the reverse.Braunstein and Kepinoff 35 contend that the increased formationof antitrypsin is due to cell degra.dation and t.he setting free ofintracellular proteolytic or autolytic enzymes.They show that theantitryptic action of the serum can be increased by the injectionintraperitoneally of liver or carcinoma paste if the material is notpreviously heated. I f it is heated before injection, no increasedantitrypsin formation is observed.I n other words, antitrypsin is32 Biochm. Zeitsch., 1910, 27, 170 ; A., ii, 786206 ANNUAL REPORTS ON THE PROQRESS OF CHEMISTRY,nature’s reply to the injection of an antigen, or to the liberation ofantigens by cell degeneration. Such a view has much to commendit, for it, is analogous to what so often occurs in other cmes. If it iscorrect, antitrypsin formation is a mere accident in carcinomatousmetabolism.Exactly the same fundamental questions arise in relation to otherenzymes, but of these only two series of researches are sufficientlyripe for mention. One of these relates to peptolytic enzymes, theelaboration of the methods for the detection of which belongs toAbderhalden.36 Various tumours of mice and men were investi-gated, but the activity of the enzymes presenf in comparison withthose of normal tissues exhibit mainly a difference of degree ratherthan of kind.One difference of kind was, however, noted, namely,that the juice from malignant tumours produces cleavage of silkpeptone, whereas that of normal tissue (liver) does not. Dog’sserum normally contains no peptolytic (or erepsin-like) enzymes, SOdiffering from the normal serum of rats and mice; in dogs withmalignant tumours, however, some preliminary experiments indicatethat peptolytic enzymes are present in their serum.The second series of investigations relate to the influence of serumon the lipase of pancreatic juice; this has been carried out byRosenheim and Shaw-Mackenzie.37 These observers find that serumaccelerates the activity of pancreatic lipase ; the accelerating sub-stance in the serum dialyses, and is soluble in dilute alcohol; it isinhibited by cholesterol. This power of serum is much less inhuman than in animal serum, except in certain pathoiogical con-dit,ions, of which cancer is one, and the lipoclastic acceleration of theserum runs parallel with its antitryptic power. Since then, Shaw-Mackenzie has found that this lipoclastic acceleration is very highin mice which will not “take” cancer grafts. This is a point infavour of the view that this power is part of the protectivemechanism. If so, is it possible to ensure protection by methodswhich will increase this property of the blood? This is one of themany unanswered questions that a study of cancer raises.All attempts to find any special toxin in cancerous tumours, anyspecific prot.ein or nucleoprotein, any peculiarity in the nature orproportion of protein cleavage products 38 have yielded absolutelynegative results. The biochemistry of the tumour does not seemto differ from that of normal tissues except in such circumstance8as rate of growth, and assimilation of protein material. Cramer and:j6 Abderhalden and others, Zeitsch. physiol. Chsm., 1910, 66, 265, 277 ; 68, 312 ;A., ii, 636, 980.37 Proc. physiol. SOC., 1910, viii, xii, xiv ; A , , ii, 517.38 Abdcrhalden axid Medigreceanu, Zeilsch. physiol. Chem,, 1910, 69, 66 ; A,,ii, 1093PHYSIOLOGICAL CHEMISTRY. 207Pringle3Q find that, weight for weight, cancer cells contain onlyabout three-quarters of the protein in ordinary tissue cells, so thata large mass of tumour is built from a comparatively small weightof protein food; the abiuretic products, however, are slightly moreabundant in cancer than in normal cells. This, again, is not acharacteristic of carcinomatous growths, for foetal tissues and otherrapidly growing tissues have also a relatively low nitrogen per-centage.So far, then, chemists, like the bacteriologists, have in theirinvestigation of cancer drawn mostly blanks. This circumstance,however, has not yet shaken my conviction that in the future thechemist is more likely than anyone else to draw the winning card.W. D. HALLIBURTON.39 Prtic. Boy. Stir., 1910, 13, 82, 307, 315 ; A . , ii, 635

ISSN:0365-6217    

DOI:10.1039/AR9100700186

出版商:RSC    

年代:1910

数据来源: RSC

摘要:

AGRICULTURAL CHEMISTRY AND VEGETABLEPHYSIOLOGY,DURING the year 1910 no outstanding paper has been publishedcomparable to Russell and Hutchinson's work which appearedduring 1909, but activity has been well maintained in all depart-ments of the subject', and particularly in connexion with VegetablePhysiology several valuable and suggestive investigations have beenreported. No additions have been made during the year to ourknowledge of the action of protozoa in the soil, although. severalindependent investigators have arrived at results which fit in withthe theory outlined by Russell and Hutchinson, and in a generaldiscussion on the subject which took place at the Sheffield meetingof the British Association some promising applications to practicewere reported in connexion with the treatment of greenhouse soilswhich, although rich in manure, rapidly become unsuited forvegetation, and again in connexion with the treatment of the soil ofsewage farms.I n the latter case, it is well known that after theuse of excessive quantities of sewage the soil ceases to function inpurifying the effluent, and this seems to be connected with such adevelopment of protozoa under the favourable conditions that thebacterial actions are reduced to a minimum, although they may bsrapidly restored by submitting the soil to some of the processes ofpartial sterilisation. *One congress of some importance to agricul-tural science was held during the year, that on " Agregeology " asa, section of the International Geological Congress a t Stockholm ;there some interesting discussions took place on the classificationof soils and on the limits of size to be adopted for the fractionsinto which a soil is divided by chemical analyses.Soils.I n previous reports 1 I have discussed various points connectedwith the theory of soil productiveness and the action of fertiliserswhich has been advanced by Whitney and his colleagues of theBureau of Soils in the United States Department of Agriculture,1 Ann.Rrporl, 1907, 265 ; 1908, 246 ; 1909, 191AGR tCDL'I'URAL CHEMIS'I'RY AND VEGETAB3LE PHYSIOTJOGY. 209but i t has always been somewhat difficult to follow the progress ofthe work. I n the first place, it. has been printed piecemeal as it,arose in the laboratory, and the bulletins are to be found in very fewplaces in Great Britain, Secondly, they are written in a semi-popular style, so that the worker in the same field is rather apt tosuspend his judgment until he can see a little more of the experi-mental foundation and criticise the data.A t any rate, from onecause or another, the theory has received but little recognition inEurope, nor have the novel points of view advanced obtained theconsideration they deserve. During the year, however, F. I(.Cameron,2 who has been associated with Whitney from the outset,has published a general survey of the whole field, and although theexperimental data are necessarily omitted, the reader has now thetheory set out in reasonable compass and accessible form, providedwith references to the original papers that contain such data as havebeen given.The author's main object is to controvert the general idea that thaprincipal function of the soil is to supply nutrients to the plant, andthat fertilisers are added to the soil to supply the nutrients whichare lacking or in deficient quantity, H e begins by discussing ther81e played by the water in the soil in its relation to the solids, andafter dealing with the physical actions in which it shares, he takesas a starting point the conclusion that the plant draws its nutrimentsolely from the solution formed by the action of the soil water onthe soil particles.Now Cameron concludes, on physico-chemicalgrounds, that this solution must be always of approximately thesame strength, whatever the soil or whatever the treatment it hasreceived in the way of fertilisers, because tlie addition of a fewpounds of phosphoric acid to a hundred thousand times its weightof soil already containing two or three thousand pounds of phos-phoric acid, and with an enormous absorbing power for thatmaterial, cannot influence to any sensible degree the concentrationof the soil water in the phosphoric acid.Similarly with potashand the other mineral constituents of the plant. The amount ofnitrogen in the soil solution is governed by other considerations,and in the main the argument refers to the mineral and not thenitrogenous nutrients of the plant. It is a difficult matter to obtainsamples truly representing the soil water, but the evidence points tothe extracts from all soils being of approximately uniform com-position.Moreover, plants flourish in water cultures of extremelylow concentration, far below that prevailing in any of the naturalsoil solutions, nor is growth accelerated by any increase in theirstrength.' J. Physical Chew., 1910, 14, 320, 393; A., ii, 646.REP.-VOL. VII. 210 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Putting aside the nitrogenous components, it would follow thatall soils must behave alike as regards their power of supplyingplants with their mineral constituents, and that mineral fertiliserscan have no direct action in supplying the plant with its food.As this conclusion does not agree with experience, some other factormust be sought which determines the differences undoubtedly exist-ing between the response of crops on particular soils to mineralfertilisers.The next step in the argument was the examinationof aqueous extracts from various soils by the method of watercultures. It was found t.hat plants would grow in these extracts,where they substantially behaved in the same relative fashion aswhen growing in the soils themselves, either in the field or in pots.The extracts from good soils yielded good plants, while the poorsoils transmitted their indifferent crop-producing powers to theiraqueous extracts. Nothing in the analyses of these extracts asregards their concentration in plant nutrients would account forthe differences in growth exhibited; in fact, dilution of some of thepoor extracts resulted in no falling off in growth, but at a certainstage even an increase.Hence the author concludes that the poorextracts and, in their turn, the poor soils contain certain toxicsubstances which inhibit the growth of plants. This was confirmedby finding that shaking up the poor extracts with such absorbentmaterials as animal charcoal, precipitated alumina, or ferric oxidemade them capable of carrying good growth, although these sub-stances could not possibly have added to the nutrients in the solution.Certain commercial fertilisers had the same beneficial effect on thesolution, as had treatment with minute quantities of pyrogallol andlime. From this it was concluded that the toxic substances must becomplex organic compounds, which are destroyed or precipitated bythe treatment employed.A search was then made in some badsoils for organic materials of a toxic nature, and several suchsubstances were successfully isolated, some of which proved to betoxic to plants in water culture. The author finally correlates thedeterioration of soils under the continued growth of one crop withan accumulation of such toxic substances characteristic of a par-ticular plant, and concludes that the value of rotation or a barefallow or of the ploughing in of a green crop is due to the oppor-tunities afforded for the oxidation or precipitation of the toxins.Furthermore, the usual fertilisers are considered to act indirectly infitting the soil for the growth of crops rather than in the directsupply of plant food.I do not propose to repeat here any of the criticisms which havefrom time to time been offered against some or other of the detailsof Whitney and Cameron’s theory, of which the above is a verAGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 2 11summarised outline.One’s general feeling is that nearly everystep in the argument is open t o some objection either as to faohor interpretation, and one doubtful deduction is based on anotheruntil the seeming logic of the whole argument leads to somethinglike topsy-turveydom. Moreover, the final conclusion does not agreewith field experience of the action of fertilisers, and it must beremembered that in Europe there is much more minute acquaintancewith the effect of particular fertilisers on particular soils and cropsthan as yet prevails in America with its comparatively extensivemethods of farming.It is probably the latter fact that has con-tributed so largely t o the neglect of Whitney and Cameron’s theoryin Europe, but now that a general statement has been put togetherin an accessible form, it should receive the consideration of othersoil chemists, for whatever their final conclusion about it may be,they cannot fail to find it stimulating and suggestive in a veryhigh degree, suggestive, above all, in driving home the extremecomplexity in the processes going on in the soil. It represents thefinal destruction of what we might call the old Liebig mineraltheory, that the one thing needful to fertilise the crop was to putinto the soil the substances the crop takes out; incidentally, also,the illusion that one can determine the available as distinct fromthe total plant food in the soil is again dismissed. This idea wasproposed, only to be discarded by Daubeny seventy years ago, but,like so many mistaken points of view, it seems to possess perennialvitality .Although no absolute distinction can be drawn between availableand total plant food in the soil, the opinion continues to grow thatinformation that is of value towards forming an opinion of thefertiliser needs of the soil can be best obtained by a determinationof the amount of phosphoric acid and potash soluble in an aqueoussolution of carbon dioxide, which is, after all, the chief solventnaturally at work in soils.I n this connexion, E. A. Mitscherlich 3has published a critical study on the solubility in water containingcarbon dioxide of the materials present in fertilisers and soils. H eascertained the influence on the resulting concentration of suchfactors as time, temperature, proportion of carbon dioxide, and theratio of the amount of solvent t~ that of material. The results do not,however, permit of summarisation, but should receive the attentionof workers in this subject. In another paper the same author4investigates the question of whether crop production is influencedat all by the strength of the soil solution in carbon dioxide, whichin the laboratory determines its solvent power over minerals.Hearranged a series of pot experiments of given soils and manures,3 Landw. Jahib., 1910, 39, 299. Bid., 157 ; A., ii, 236.P 212 ANNUAL REPORTS OX THE PROGRESS OF CHEMISTRY.watering some with tap water and others with water containingvarious amounts of carbon dioxide, but obtained no increased yieldfor the carbon dioxide. He concludes that a small amount ofcarbon dioxide is sufficiently effective, and that under natural con-ditions there is always a sufficient production from the roots andfrom the oxidation of organic matter, hence the application offertilisers designed specially to increase the amount of carbondioxide in the soil gases is needless. The use of carbon dioxidesaturated water as an analytical agent to deal with soils is alsorecommended by BiBler-Chatelan.5Arising out of his work with Hutchinson on protozoa, E.J.Russell has investigated the amount of ammonium compoundspresent as such in soils. Considerable uncertainty attaches t o thedeterminations of ammonia in soils, because in the methods usuallyadopted the alkali attacks some of the organic nitrogen compounds,and there is a continuous evolution of ammonia as long as the distil-lation is continued. Russell finds that distillation with alcoholicpotash (0.5 to 1.0 per cent.) at reduced pressures (32-35 mm.) showsa sharp end-point at which the evolution of ammonia ceases, and forsoils not too rich in organic matter the same end-point is reachedby a single distillation with magnesia and water at the same lowtemperature and pressure. This point Russell considers to representthe conclusion of the evolution of the nitrogen in the soil that wascombined as ammonia.Only one or two parts of ammonia permillion of soil are found in ordinary soils, rising in very rich gardensoils to five or six. This is because the ammonia is kept down to alow limit by its conversion into nitrate by the nitrifying organisms.Thus under field conditions the factor limiting the formation ofnitrates is really the preliminary ammonia producing process, andinstead of the rate of nitrification it is really the rate of ammoniaproduction that determines the amount of nitrogen available for thecrop.As bearing on the soil materials available for growth, S. U.Pickering 7 has continued his examination of the chemical changesbrought about by heating the soil for a short time to various tem-peratures above and below looo.He confirms his previous results,that at all temperatures, but especially at looo and above, there is aconsiderable formation of soluble organic matter which will serve asplant food, but is toxic in its nature, as shown by its injuriousaction on the rate of germination of seeds. This injurious material,however, gradually decomposes, probably by oxidation, because theinjurious effect disappears when the soil in a moist condition isexposed to the air even under aseptic conditions.Compt. rend., 1910, 150, 716 ; A . , ii, 453.J. Ayric. S&., 1910, 3, 233 ; A., ii, 1104. 7 B i d . , 258AGRICULTURAL CHEMISTRY AND VEGETAELE PHYSIOLOGY.2 13E. J. Russell 8 has also been working a t the often debated questionof the value of earthworms in cultivated soils. They have generallybeen regarded as increasing the productiveness of soil by decom-posing the organic matter and preparing it for the action of themicreorganisms. Russell shows thah previous experimenters havebeen misled by the nitrogen introduced into the bodies of theearthworms themselves; when this is allowed for, they seem tohave no particular effect on the decomposition of organic matterand the production of nitrates. They have, however, considerableeffect as cultivators, loosening and mulching the soil, and this mayultimately bring about some action on its fertility, althoughexperimental demonstration would be difficult.Among the papersdealing with soil materials, mention may be made of one byH. Mieth,g who tried a series of vegetation experiments in whichhe employed calcium silicates as sources of calcium. He foundthat plants easily decompose such precipitated silicates and cantake up the calcium from them, so that these compounds may serveas sources of calcium to the plant instead of the carbonate, andthis fact the author correlates with the maintenance of neutralityin many soils which show on analysis only a trace of calciumcarbon ate.H. E. Annett lo reports an interesting fact regarding the colour ofcertain black cotton soils which occupy an area of over 200,000square miles in India. These soils are not rich in organic matter,and remain black after oxidation with sulphuric acid.The colourproves to be due to a large extent to a black magnetic compoundcontaining 73 per cent. of ferric oxide and 18 per cent. of titaniumdioxide.Soil Bacteriology.I n the domain of soil bacteria, no very novel work is reported.A. Koch l1 has continued his work on the power of Azotobacter toaccumulate nitrogen in soils to which sugar and other carbohydrateshave been added, and has obtained further results in confirmationof those previously reported. He has extended his experiments t osmall plots of soil, half a metre square, in the open air, and aftertreatment with sugar he has found that he obtained an increase ofcrop, which, although slight in the first year, was considerable inthe second and third after application.From other sources wehave evidence that the fixation of nitrogen by Azotobacter in theopen ground is much affected by the prevailing temperature; ifJ. Agric. Sci., 1910, 3, 246.Landw. Vers.ztchs.-Stal., 1910, 74, 81 ; A . , ii, 1105.lo Mem. Dqd. Agric., India, 1910, 1, 185; A., ii, 535.J. Lac1Ldw., 1909, 57, 269 ; A., ii, 60214 ANNUAL REPORTS ON THE PROGRESS OF CHEMTSTRY.this be too low, other organisms than the A zotobacter predominateas a result of the carbohydrate application. Koch has added onefurther link to the completeness of the demonstration by showingthat the addition of sugar to soils destitute of the Azotohacterorganisms results in no increase in their content of nitrogen.Koch 12 has also studied afresh the denitrification process in soils,and finds that there is but little loss of nitrogen, although bothnitrate and dextrose had been added, provided the amount of waterin the soil is kept down.For example, when the water in a par-ticular soil was below 18 per cent., there was no reduction of nitrate,but when it rose to 25 or 30 per cent., denitrification set in. I nother words, anaerobic conditions must be established before thereducing organism comes into play.Chemistry of the Growing Plant.One of the most suggestive papers of the year is that publishedby H. E. and E. F. Armstrongl3 on the action of chloroform andsimilar substances in stimulating enzyme action in living structures.Starting with t,he interesting observations of Guignard and ofMirande,l4 on the action of chloroform and similar anasthetics onthe development of hydrocyanic acid from cyanogenetic glucmidesin the leaves of laurel and similar plants, t-he Armstrongs haveproceeded to generalise the phenomena there described.They makeuse of the method discovered by Guignard, in which the green leafis placed in a test-tube with a strip of paper coloured orange-yellowwith a solution of sodium picrate. The liberation of a trace ofhydrocyanic acid results in the production of successively orange,rose, and finally a dark brick-red colour on the test paper, due tothe formation of sodium isopurpurate. Using leaves of the cherry-laurel (Prunus Zaurocerasus), which contains the glucoside pu-Zaurasin,15 no hydrocyanic acid is developed when the leaf and testpaper are alone in the tube, but the addition of a drop of chloroformis followed in the course of a few minutes by a gradual developmentof colour, the action being more rapid at higher temperatures.It was found the solutions could be substituted for the vapour,because sound leaves, partly immersed in water, give no hydro-cyanic acid in three or four days.The experiments then showedthat ths vapours of ammonia, carbon disulphide, chloroform, toluene,ether, and various alcohols were quickly active, benzene, naph-thalene, thymol, acetic acid were less so; carbon dioxide, benzene?l2 Ccsttr. Bakt. Par., 1910, ii, 26, 335 ; A., ii, 333.13 Proe. Boy. SOC., 1910, 82, B, 588 ; A., ii, 883.I4 Compt.rend., 1909,149, 91, 140; A., 1909, ii, 823, 824.l5 Caldwell and Courtauld, Tmw., 1907, 91, 671AGRICULTURAL CHEMlSTRY An’D VEGETABLE PHYSIOLOGY. 215limonene were tnly slowly active. I n solutions few salts had anyaction except in strengths that destroyed the leaf, but solutions ofsodium or potassium fluorides were active, as were solutions ofmercuric chloride and cadmium iodide and of ammonia, but notof potassium or sodium hydroxides.These results fall into line with the well-known work of A. J.Brown 16 on the semi-permeability of the membrane surroundingthe barley grain, and indicate that only those substances are activewhich succeed in penetrating into the leaf. The authors propose toextend Starling’s term of “ hormones ” to these excitants, and theypoint out that they are all substances with but slight attraction forwater ; materials which react with water generally fail to penetratethe leaf.It is generally considered that in plant tissues the enzymes andglucosides are either contained in different cells or in differentvacuoles in the same cell.Guignard states that in the cherrylaurel the enzyme is stored in the endodermis, whilst the glucosideis in the parenchyma, and as the enzyme is not diffusible, it ismost probable that the glucoside is induced to travel to the enzyme.The action is evidently bound up with changes in the con-centration of the fluids within the leaf; in his paper Guignardcompares the action t o that of frost, which induces a concentrationof the cell sap and at once sets up change.I n the leaves exposedto vapours there is sufficient water to allow of the passage of theglucoside towards the “ hormone ” entering very close to the enzymewhich lies near the exterior surface.From solutions a considerable amount of water enters the 1ea.fwith the hormone, a leaf, for example, increases in weight by 20per cent. after eighteen hours’ immersion in chloroform water,whereas it only gains 5 per cent. after twenty-four hours in purewater, and 2 per cent. after forty-five hours in a 2 per cent. solutionof sodium chloride.The authors discuss these results in the light of H. E. Armstrong’stheory of the constitution of water, and then proceed to show theirapplication to a number of phenomena in the life of animals andplants.As regards plants, one of the most significant facts is thatcarbon dioxide itself acts as a hormone; it is easy to suppose thatvariations in the presentation of this substance to the cell mayexcite enzymic action in the direction of hydrolysis or thereverse, the most significant of the processes in the metabolismof the cell. Moreover, a slight initial excitation may be suficientto set in motion considerable change, because many of the productsof hydrolysis, for example, hydrocyanic acid and benzaldehy de, itrel6 Proc. Eoy. Soc,, 1909, 81, B, 82 ; A , , 1909, ii, 386216 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.themselves hormones and would extend the action. I n the livingplant, the hormone-excited changes can never be so large as in theexperiments on the detached leaves, for A.D. Waller I7 shows thatthe leaf is killed within a minute of the action of the chloroform, asmay be ascertained from the abolition of electrical response.Doubtless from these experiments light will eventually be thrownon the physiological function of many of the ethereal oils, terpenes,and scents secreted by plants so normally that they cannot bewithout significance.They also throw some light on the horticultural practice whichhas been worked out of recent years, by which plants like lilacsintended for forcing are exposed to the vapour of ether for twenty-four hours or so. After the etherising process, it is found that theplants can be forced into bloom a, week or ten days earlier thanwould otherwise have been possible.As cold acts in the sameway by altering the concentration of the cell sap, we may alsocorrelate the similar acceleration of flowering that is induced bya preliminary cold storage before forcing, and, again, the well-knownfact that potatoes which have been frozen become sweet throughan accumulation of enzyme-produced sugar. I n a paper on theripening of premature fruit, A. E. Vinson 18 shows that dates whichhave reached a certain stage of development can be made to ripenby exposure to certain vapours or solutions, practically the samesubstances which the Armstrongs have found to be active. Vinsonsimilarly concludes that the ripening is brought about by the releaseof the intercellular enzymes through substances penetrating thecuticle and stimulating the protoplasm.The field of work thus opened up is extremely suggestive, andpromises not only to throw light on many of the processes of theliving plant, but also to find certain immediate practical appli-cations.Various papers dealing with assimilation have been publishedduring the year.S. B. Schryver19 has taken up afresh the workof Priestley and Usher on the photochemical formation of form-aldehyde by chlorophyll. He finds that grass, when washed withwarm water, yields no formaldehyde, but when the grass isextracted with alcohol and the dried extract is heated with ether,then formaldehyde can be detected. Hence he concludes that inliving plants the chlorophyll contains formaldehyde in combination.He next obtained films of chlorophyll by evaporating a 1 per cent.solution in ether on glass slips at the ordinary temperature.TheseI7 Proc. Roy. SOC., 1910, 82, €3, 571; compare A . , ii, 741.l8 J. Amer. Chew Soc., 1910, 32, 208 ; A., ii, 336.Is Proc. Roy. Soc., 1910, 82, B, 226 ; A., ii, 334AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 2 17were exposed to moist carbon dioxide and t o air freed from carbondioxide by soda-lime, both in sunlight and in the dark. No form-aldehyde was detected after exposure in the dark, and very littleon the slips which had been kept over sod&lime, but a distinctreaction was obtained in sunlight. Schryver concludes thatchlorophyll can form formaldehyde directly, but that it rarelybecomes sensible because it does not accumulate in the cell, sinceit is withdrawn to form sugars as fast as it is formed. He employeda sensitive form of Rimini’s test for formaldehyde (phenylhydrazinehydrochloride with potassium ferricyanide and hydrochloric acidgives a brilliant magenta colour in presence of formaldehyde), whichwill detect one part in a million, and can be made quantitative.Thoday20 has examined in detail Sachs’ method of measuringassimilation by the difference in dry weight of comparable areas inthe two halves of a leaf before and after exposure to light.Hehas succeeded in improving the method by eliminating certainerrors, particularly those due to shrinkage of area, t o which themethod is liable. He obtains rates of assimilation (17 milligramsper hour per square dcm.) even higher than those of Sachs, andmuch higher than those obtained by Brown and Escombe.Thelow figures of the latter workers he considers to have been due to thehigh temperature prevailing in the glass cases in which their leaveswere confined, and to the resulting lack of turgor in the leaveswhich would result in only a partial opening of the stomata.R. Willstatter 21 and his colleagues have continued their investi-gations on the const’itution of chlorophyll. They had beforeestablished the existence of two chlorophylls, one amorphous-aphytol ester containing one phytol residue and one methoxyl groupfor each magnesium atom-and the other crystalline, yielding, onhydrolysis, pheophorbin, which is a dimethyl ester.The authorshave now examined the distribution of these chlorophylls in anumber of plants from the various orders. From experiments withgrass, plantain, and nettles, they find that the nature of thechlorophyll is not influenced by the soil or the time of the year.The amorphous phytol ester, chlorophyll, is widely distributed andpreponderates in some cases. Crystalline chlorophyll is not alwaysfound. Colorimetric determinations show that the lesves of variousplants contain half to one per cent. of chlorophyll in their drymaterial.The question of the action of small traces of metallic salts andother possible catalytic agents on the growth of plants has againreceived a good deal of attention during the year. For example,Proc.Boy. Soc., 1910, B, 82, 421 ; A , , ii, 800.2L Willstatter, F. Hocheder, and E. Hug, Annalen, 1910, 371, 1 ; A., ii, 150218 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in the Rothamsted Laboratory, W. E. Brenchley 22 has examinedin considerable detail the effect of the sulphates of copper andmanganese on the growth of barley in water cultures. It has beenmaintained that all substances toxic to plants a c t as stimuli atsome stage of high dilution, but with copper sulphate the authorcan find no evidence of stimulus even down to a dilution of one partin 10 millions of water. The toxic effect was always manifest,although it was greatly reduced when the copper was added to asolution of nutrient salts and not used in water alone. I n thelatter case, seedlings are very susceptible, being checked and evenstopped in growth by the use of water which has been distilledfrom the ordinary copper vessels in the laboratory.The stimuluseffect which had been reported from time to time may have eitherbeen due to accidental variations, since the individuality of plantsgrown in water cultures is very marked and large numbers mustbe taken in order to obtain smooth results, or else to some secondaryaction of the toxic substances on bacteria, etc., in the culturemedium. Manganese sulphate can hardly be regarded as toxicfor barley; although in moderate concentrations (more than one in10,000) there was retardation of growth, at lower concentrations,one per 100,000 and downwards, there was distinct evidence ofstimulus.Incidentally i t was noted that at such concentrations asone per 10,000, the manganese taken up by the plant was excretedas peroxide on the surface of the leaves. As manganese is usuallyfound in plant ashes, and has been considered by Bertrand andhis co-workers to aid in the action of the oxydases of the leaf, itobviously stands in a different position, and cannot be comparedwith substances like copper which are toxic and have no normalphysiological function.I n the same line of work comes a paper by P. Ehrenberg23 onthe effect of zinc salts on vegetation. Zinc he finds to be alwaystoxic when the action is simply between the plant and the reactingsubstance. I n his experiments on soil, however, cases were metwith of apparent stimulus due to zinc, but the author considers thatthese can always be explained by some indirect chemical or biologicalaction of the zinc on the constituents in the soil, rather than toany stimulating action of the toxin on t'he plant.Ehrenberg con-cludes that zinc vessels ought never to be used in vegetationexperiments, although one of the most commonly employed typesof vessel for pot culture work is made of zinc,P. Koenig24 also reports a long series of experiments on theact.ion of chromium salts on vegetation, in which he claims to2 3 An/(. of Botany, 1910, 24, 571 ; A . , ii, 859.z3 Lnndw. Versuchs.-Stat., 1910, 73, 15; A , , ii, 236.24 Lnndw. Jahrb., 1910, 39, 775AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY.21 9demonstrate that both the chromium salts and the chromates,although normally toxic, may act as stimuli. The concIusion as tostimulus is, however, vitiated by the fact that the additions ofchromium were always made to soil in which the test plants weregrowing. So involved are the actions taking place in the soil, theresultant only of which is represented by the growth of the plant,that one has no right to draw any conclusions from such experi-ments as to the direct action on the plant of the material underinvestigation.Amongst other work dealing with the living plant which possessessome economic interest is a paper by Otto and Kooper25 on thechanges of the composition of fruit as it ripens after gathering.The experiments were made with sloes, and the authors found thatin the ripening process the lmwlose increased while the dextrosedecreased, and during the same time both the acids and the amountof tannin markedly decreased.The decrease in acid and tanninwas larger than the net increase of sugar, the difference no doubtrepresenting losses by respiration, and the authors considered thatthe other figures indicated a change from dextrose to lzvulose, achange, however, which is very difficult to credit.Another paper, although a contribution to the study of genetics,is yet of general interest to plant-physiologists because of itspossible bearing on enzyme actions in living plants, is one by M.Wheldale26 on the inheritance of colour in certain sweet peas andstocks.I n these flowers the colours are due to anthocyanins, whichare the oxidised products of the action of an oxydase on achromogen. Both must be present in the same flower to causecolour, but as all the white flowers contain the chromogen, theirabsence of colour must be due to a lack of one or other of thefactors (peroxide and peroxydase) making up the oxydae system.Investigations of white flowers which on mating will yet throwcoloured blooms confirmed this theory; in the extracts of some ofthe white flowers no evidence of oxydase was found, whilst in othersthe peroxide factor was lacking. The two factors are inheritedseparately on Mendelian lines, and, on mating, coloured flowers maybe produced when the two factors are again united in the samecell.Manures and Manuring.During the year little work on fertilisers has been reported beyondthe usual stock experiments on the effect of these materials whenused with different crops and soils. Various new materials haveZcitsclt.Nnhr. Genussm., 1910, 19, 10 ; A . , ii, 233.26 Roy. Xoc. Report to Evolution Committee, 1909, V, 26 ; compare A . , 1909,ii, 604220 ANNUAL REPOnTS ON THE PROGKESS OF CHEMISTRY.been brought forward, but none of them represent any freshdevelopment or utilisation of a novel principle as did the nitro-genous manures generated from the atmosphere. I n the latterconnexion, the changes taking place when cyanamide is applied tothe soil continue to attract a good deal of attention, and C. Ulpiani 27gives an account of a long series of experiments on this question.H e dismisses the idea originally suggested by Lohnis that bacterialactions play any considerable part in breaking down the cyanamideto the stage of ammonia. He regards the action as chiefly broughtabout by the colloidal surface of soil particles, which acts as acatalyst.The change ceases when this is de'stroyed either by heatingthe soil or by treating with acids or alkalis, but can be restored bythe addition of precipitated silica. The cyanamide changes firstinto carbamide, and then into ammonium carbonate, but Ulpiani canfind no evidence for Lohnis' idea that a, formation of ammoniumcyanate precedes the carbamide. The change takes place in thepresence of antiseptics and with sterilised materials; it also goes onwith increased velocity a t looo; again it is most rapid at first, andthen falls off.It also increases with the concentrations of thesolutions taken. None of these facts agrees with the theory thatthe change is brought about by bacteria. The soil absorbs theammonia as it is formed, and this removal of the products acceleratesthe rate of change, and also prevents polymerisation into dicyano-diamide. Because of the susceptibility of cyanamide to change inmoist air and the formation of the toxic dicyanodiamide, C. Brioux 28has worked out a method for the analysis of the altered product.This method depends on the fact that the precipitate whichcyanamide gives with silver nitrate is insoluble in ammonia, whereasthe precipitate similarly formed by dicyanodiamide is soluble.Methods for the estimation of nitrates continue to attract a gooddeal of attention, because the determinations with the nitrometeror as nitric oxide by Schloesing's process are not particularlyconvenient.It is obviously preferable to reduce the nitrate toammonia, which can be rapidly and accurately measure6 5y theroutine methods of the laboratory. M. E. Pozzi-Escot 29 employedfor this purpose aluminium, together with a little mercuric chloride,so as to form an aluminium-mercury couple which reduces thenitrate to ammonia in a few minutes. This method has, however,been severely criticised ; Cahen 30 dismisses it as untrustworthy, andwould replace it by Devarda's method, in which the reduction iseffected by 2 or 3 grams of alloy containing 45 per cent.of2/ Gazzettu, 1910, 40, i, 613 ; A . , ii, 890.28 A ~ U L Chim. axal., 1910, 15, 341 ; A . , ii, 1010.29 Bull. Assoc. Chim. Sucr. dist., 1909, 27, 457 ; A . , ii, 71, 153, 652.3O Analyst, 1910, 35, 307AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 221aluminium, 5 of zinc, and 50 of copper. This is digested with thenitrate-containing makerial for half an hour in the presence ofconcentrated sodium hydroxide, the digestion flask being connectedfrom the outset by the distilling apparatus. The distillation isthen completed and the ammonia collected in the standard acidas usual.J. M. Wilkie 31 has discussed a method of determining ammonia,which may on occasion become useful to the agricultural analyst.The solution is rendered exactly neutral, and neutral formaldehydeis added.The acid which results from the abstraction of theammonia by the formaldehyde is titrated with baryta water, usingphenolphthalein as indicator.Chemistry of Animal Nutrition.Papers dealing with animal nutrition have been rare in thiscountry, but there are not wanting indications that work on thisimportant subject is beginning in Britain, and we are pleased tobe able to report on one interesting piece of work that has appearedduring the past year. I n some earlier papers, T. B. Wood32 hasshown that certain constant differences exist in the composition ofthe various kinds of mangolds usually grown. Their average contentof dry matter varies from 10.7 per cent.in the “Yellow Globe”to 13.1 per cent. in the “Long Red” and yellow-fleshed varieties.Since the “Long Red” yields on the average as large a crop asthe “ Yellow Globe,” and a much larger one than the yellow-fleshedvarieties, it produces the most dry matter per acre, and should bethe most profitable mangold to grow. To make this conclusionvalid, however, it was necessary to show that the dry matter of the‘‘ Long Red ’’ variety possesses equal feeding value to that of theothers, and accordingly the author carried out a series of sevenexperiments on fattening cattle, using thirty-seven animals in all,comparing in each case the effect of equal weights of (‘ Long Red ”and “ Yellow Globe ” mangolds. The final result shows a superiorityof the “ Long Red” as compared to the “Yellow Globe” of 116 to100 in their power of producing live-weight increase, the proportionof dry matter being as 120 to 100.Two other experiments showedthat “ Long Red ” and yellow-fleshed mangolds possess equal feedingvalues, the percentages of dry matter being approximately the samein the two varieties. The limits of experimental error obtaining inthe trials are discussed, and the final result mag be taken as con-clusive that the feeding value of the mangold is determined =31 J. SOC. Chem. h d . , 1910, 29, 6 j A . , ii, 240.32 J. Agric. Scsci., 1910, 3, 225282 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.closely as it can be measured in practice by the percentage of drymatter in the roots.I n the field of animal nutrition interest is now chiefly fixed onthe proteins and their cleavage products, as it is felt that themain lines of the energy question are settled. Abderhalden 33 andhis co-workers continue to improve upon their attempts to feedanimals with the cleavage products instead of the proteins them-selves, and have now attained a much greater measure of success.They found that dogs could maintain their nitrogen equilibriumon the deficient cleavage products of meat, whether hydrolysed bypepsin, trypsin, and erepsin, or by acid, provided that care was takento remove the traces of barium which acted prejudicially in theirformer experiments.When the products of acid hydrolysis areadministered, it is desirable to add tryptophan, because this sub-stance is t o a large extent destroyed by the acid.OsborneS4 has continued his work on the cleavage products ofproteins, and in an important paper, in which he sets out as fullyas possible the cleavage products of zein, he shows a recovery ofsomething like 80 per cent.He discusses at length the sources ofloss which still exist in all methods of protein hydrolysis.Kellner35 has continued his work on the value of non-proteinnitrogen compounds in the nutrition of ruminant animals. Lambswere fed as to their nitrogenous requirements exclusively onasparagine and ammonium acetate. The result showed that thesesubstances can be so converted by the bacteria of the intestinesinto protein that they can replace some of the protein requiredfor maintenance.There was, however, no evidence of productionof flesh from these non-proteins, but when fed together with proteinthey can increase the formation of flesh by saving the proteinrequired for maintenance. The same question has also been investi-gated a t the Hohenheim where ammonium acetate andasparagine were fed to milch cows. The authors conclude thatthese substances do not lead to any increase in the undigested proteinin the faxes, although they are converted by bacterial action intoproteins which may be utilised by the animal, not merely formaintenance, but also for milk production.Among other papers interesting to the agricultural chemist isone by Siegfeld37 on the constitution of butter fat. H e finds that33 Zeitsch.physiol. Chem., 1910, 64, 158 ; A., ii, 322.A., i, 59s.3 j 0. Kellner, P. Eisenkolbe, R. Flebbe, and R. Neumann, Landw. F'ersziclis. - T. B. Osborne and L. PI. Liddle, Anzer. J. Physiol., 1910, 26, 295Stat., 1910, 72, 437 ; A . , ii, 424.A. Morgen, C. Berger, and F. Westhausser, iEzd., 73, 285.37 Milchw. Zentr., 1910, 6, 122 ; A., ii, 327AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 223tributyrin is soluble in alcohol, by which it can be extracted from amixture of beef butter. Butter, however, yields very little fat toalcohol, and that of much the same composition as the original fat :from which he concludes that Bell's original conception of butterfat as mixed glycerides is most likely to be correct.T. Weyl38 has examined the precipitation of proteins by acetoneas a basis for analytical processes.He finds that acetone precipitatesthe protein from milk completely; the milk is diluted with an equalvolume of water, four volumes of acetone are added, and thecollected precipitate, after washing, is extracted with ether, dried.and weighed. It is possible that this method of precipitatingproteins with but little change may become useful in plant analysis.As regard the nutrition of farm stock, the most notable eventof late years has been the introduction of the soya bean fromManchuria, and the considerable trade in soya bean cake whichhas thus developed. Although the ordinary analyses show that onewas dealing with a very rich material, only paralleled by decorticatedcotton cake, direct experiments on its digestibility were not avail-able, but one had to assume that i t would probably fall intoline with similar concentrated foods and prove very completelydigestible.F. Honcamp39 now reports certain determinations of thedigestibility by sheep of soya bean meal, made both from thepressed cake and from the residue after the oil had been chemicallyextracted. The following table will show that the meal is themost concentrated of all feeding stuffs in common use, with theexception of linseed from which the oil has not been extracted:v- - Piess cake. Residw.Total. Digestible. Total. Digestible.Crude protein ............ 47 ' 9 43 .?I 52.2 48 *ONitrogen-free extract ... 32 S 31 *1 34.6 34.6Crude fat .................. 7'9 6'9 1 *s 1 -2Crude fibre ............... 5 6 4'4 5.3 5.2 - w-Starch equiv. .......... 92 86It has long been recognised that a certain amount of care mustbe exercised in feeding stock with cottonseed cake; from time totime injurious results have been reported, as though the feedingstuffs contained some toxic substance, but the experiences werenot consistent, and attempts to isolate a poisonous constituent havenot been successful, although cholin and betain have been foundand credited with the harmful action. In practice farmers havefound it wise not to feed cotton cake to milch cows near calving,38 Ber., 1910, 43, 508 ; A., i, 287.39 Laizdw. Yersuchs.-Ss'tat., 1910, 73, 241224 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.nor to young stock. A. C. C r a ~ f o r d , ~ ~ after a series of chemicaland physiological experiments, now attributes the toxic results tosalts of pyrophosphoric acid, the compounds being in some mealsinorganic, in others probably organic. Seed of upland cotton ismore generally poisonous t(han that from Sea Island cotton, althoughthe latter becomes toxic if it is heated in the process of extractingthe oil, due to the conversion of ort.ho- into pyro-phosphates.Crawford’s conclusions seem to be well supported by his experi-mental work, and it should be noted that a t least one previousworker has found pyrophosphates in cottonseed meal and has drawnattention to their poisonous character.A. D. HALL.4o J. €‘liarin. Rxp. Ther., 1910, 1, 519

ISSN:0365-6217    

DOI:10.1039/AR9100700208

出版商:RSC    

年代:1910

数据来源: RSC

摘要:

MINERAL0 GICAL CHEMISTRY.FROM a purely mineralogical point of view the year 1910 cannotbe regarded as particularly eventful. The new minerals we haveto record are neither numerous nor specialIy remarkable, and verylittle fresh light has been thrown on the more obscure problems ofmineralogical chemistry. Large numbers of analyses of mineralshave been published, but many of these have been made ratherto aid identification than with the express object of arriving at aformula, and it will only be possible to admit to our chronicleanalyses made with special care on selected material, or whichare of unusual interest on account of the peculiar character or rarityof the species to which they refer. I n the borderland where theconfines of physical chemistry, mineralogy, and geology meet, agood deal of activity has been manifested, and there is an increasingtendency to attempt to elucidate the complex problems presentedby silicate fusions by the study of the behaviour of pure artificialsilicates and inorganic salts.Although interesting results have been arrived a t in this field,it is in another direction that progress has been most rapid.Theapplication of the Barlow-Pope theory of crystal structure to thedata of organic chemistry has rendered clear much that has hithertobeen mysterious and obscure, and has so stimulated the somewhatlanguishing study of chemical crystallography that it has seemedadvisable to include in this report a section in which the moreremarkable of the advances made may be briefly indicated.Somuch by way of preface. We will now proceed t o the discussion ofthe various branches of our subject, following in the main theorder and mode of treatment adopted in past years.General and Physical Chemistry of Hinerals.Mutual Relations of Fused Silicates or Salts.-The remarkablework of Day and Allen on the artificial production of plagioclasefelspars brought strong evidence from the synthetic side in favourof the view that these substances form a continuous series of mixedAim. Beport, 1905, 268,KEP.-VOL. VIL. 226 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.crystals conforming to type I of Bakhuis Roozeboom's classification.These results, obtained by the study of heating and cooling curves,have been fully substantiated so far as the anorthite-labradoriteportion of the series is concerned, by a series of experiments carriedout by E.Dittler,2 a member of Doelter's school. The preliminarynotice of this investigation was referred to last year, and the detailedaccount. is now before us. Eight mixtures of silica and alumina,with the carbonates of sodium and calcium, corresponding withfelspars ranging from pure anorthite to An6,Ab,,, were melted andallowed t o crystallise. The specific gravities and indices of refrac-tion of the crystalline products were determined, and by means ofa small electric furnace, combined with a microscope, the tem-peratures T, and T, were observed, at which the crystalline productsbecame respectively, rounded at the edges, or changed into isotropicglass. The temperature T,, at which crystallisation begins, andthe final temperature of solidification, T4, were also measured.These experiments differ from those of Day and Allen mainly inthe method of determining the melting points, and whereas theystate that anorthite melts sharply a t 1532O, Dittler finds for thesame substance T, = 1290°, T, = 137o0,C2', = 1300°, T4 = 1 1 8 0 O .Similarobservations were made with mixtures containing potassiumcarbonate, and corresponding in composition with mixtures oforthoclase with anorthite, bytownite, and labradorite respectively.The principal conclusions arrived at are as follows. The presenceof potash felspar favoured the production of zonal structure, theperipheral zones being most developed in the melts which containedleast anorthite.From melts containing much anorthite and littleorthoclase, anorthite containing potassium crystallised out, and theground mass consisted of a mixture of the two components. Onincreasing the proportion of orthoclase, most of it solidified as glass.I n the experiments with bytownite and labradorite, it was foundthat, the miscibility of the two components increased with theincrease in the sodium content, but for a given plagioclase the com-pmition of the crystalline product remained practically the samehowever much orthoclase was added. From this it would appearthat the plagioclases at the anorthite end of the series are only ableto take up small quantities of orthoclase, not exceeding a few percent.in the case of anorthite, and from 10 to 15 per cent. in theother felspars examined, while the molecules KAlSi,O, andNaA1Si,08 have the properties of isodimorphous substances, and aremiscible.Another research3 undertaken in the same school has been2 Tsch. Min. Miitt., 1910, 29, 273.5 V. Hnenliileile, Jul~rb. &in, BciL-Ed., 1910, 29, 719 ; A., ii, 721A4 I NERALOG ICA I, CHE hI ISTRY. 227prompted by the criticism directed against some of the earlier workon the interactions of fused silicates. It has been contended thatthe products obtained might be greatly influenced by the presenceof impurities in the natural silicates employed. To meet thisobjection, a number of experiments have been carried out withmixtures of pure silica, magnesia, and aluminium hydroxide, withthe carbonates of calcium and sodium.When mixtures correspond-ing with labradorite + diopside were fused, a number of mineralscould be identified in the crystalline product, as, for example,diopside, sod&augite, aluminium-iron-augite, hedenbergite, labrador-ite, anorthite, magnetite, spinel, and hematite. Mixtures corre-sponding with olivine + labradorite + diopside gave similar results,and confirm the validity of the conclusions already arrived at byobservations on natural minerals. Pure materials have likewisebeen employed by 3%. Hauke4 in an investigation of a numberof eutectic mixtures, in which the proportions of the compoundswere calculated by means of Vogt’s formula; the influence ofmagnesium chloride, of calcium chloride, and of tungstic acid inpromoting crystallisation was also examined.Mixtures correspond-ing in composition with eutectics of anorthite + olivine, labradorite +olivine or diopside, oligoclase + enstatite, nepheline + diopside, anddiopside + olivine were fused, and the order of crystallisstion andthe micrclstructure of the products determined in each case. Thoapplication of the laws of eutectics to fused silicates has also beendiscussed by F. M. Flawitzky.5 Whilst unable to agree with Vogtthat the molecules of these silicates are not polymerised, he findsevidence in favour of the view that the degree of polynierisation isthe same in each case.Work of a similar character to that recorded above has beencarried out in a number of other cases, and some of these mayclaim brief notice here.I n the first place, the study of fused leadsilicate has been continued,6 and some interesting results havebeen obtained. The freezing-point curve suggests the existenceof two eutectics and a maximum corresponding with Pb,SiO,. Thefirst of these eutectics has, however, been shown to consist of twoeutectics close together, with a maximum corresponding with thecompound 3Pb0,2Si02. Another compound, SPbO,SiO,, appearsalso to exist. Secondly, we may notice some work that has beendone on the binary systems formed by calcium metasilicate withcalcium chloride and calcium fluoride respectiveIy.7 I n the formercase, the eutectic point lies close to the calcium chloride point and.Jnhrb.Min., 1910, i, 91 ; A., ii, 510.Nat. Phil. SOC. I m p . Univ. Kaznn, 1909 ; A., ii, 510.ti 3. Hilpert and R. Nauken, Bcr., 1910, 43, 2565; A., ii, 955.i B. KarandCeB; Zcilsch. anorg. Chem., 1910, 68, 188 ; A , , ii, 954.8 228 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.8 O below it, whilst in the latter the eutectic point is a t 1130O andcorresponds with 48CaF, and 52CaSi0,. Lastly, we may drawattention to two other investizations conducted on similar lines. Thefirst of these deals with the relations of calcium sulphate to thealkaline sulphates,* whilst in the second the relations of the sulphateof sodium t o its fluoride and chloride are discussed,g as well as thebehaviour of the simple ternary system, composed of all three.The normal sulphates of potassium, rubidium, and czesium areenantiotropic-dimorphic, being orthorhombic at the ordinary tem-perature, and hexagonal above the transition temperatures, whichare 580°, 649O, and 660° respectively.The temperature-con-centration diagrams of each of these salts, when mixed with calciumsulphate, have been examined, as well as the systems composed ofcalcium sulphate and lithium or sodium sulphates. Potassium sul-phate forms the enantiotropic-dimorphic double salt, K,S0,,2CaS04.Compounds of similar composition are obtained with rubidium andmsium, the former being trimorphous, the latter dimorphous.Sodium sulphate gives a double salt, 4N+S0,,CaS04, completelymiscible with sodium sulphate. Glauberite, N+,S04,CaS04, cannotbe obtained from fusions, a melt of the proper composition solidify-ing as a eutectic of anhydrite, CaSO,, with mixed crystals of4N+SO,,CaSO, and CaSO,.Lithium sulphate forms neither doublesalts nor mixed crystals with calcium sulphate.Constitution of Silicates.-Tschermak's method of determiningthe constitution of silicates by studying the dehydration of thesilicic acids prepared from them continues to give rise to discussion.Tschermak 10 himself claims to have shown that the vapour tensionmethod of detecting discontinuities in the velocity of dehydrationyields results similar to those obtained by the dynamic method,although the latter is to be preferred. On the other hand, it ismaintained 11 that the concentration and temperature of thehydrochloric acid used to decompose the silicate and the tem-perature a t which the silicic acid is dried have an importantinfluence on the result, and it has been shown that the compositionof the silicic acid obtained from leucite varied between H,,Si,O,,and H,Si20,.Electrical Conductivity of Minerals.-As the result of anelaborate investigation into the electrical conductivity of mineralsboth in the crystalline and fused conditions, C.Doelter12 classifiesthese substances as follows: (A) Those which exhibit metallic con-* H. Miiller, Jahrb. illin. Bei1.-Bd., 1910, 30, 1 ; A , , ii, 776.lo Zeitmh, anorg. Chm., 1910, 66, 109 : A , , ii, 407.l1 A. Serm, Atti B. Aced, Lincei, 1910, [v], 19, i, 202 ; A , , ii, 407,13 Moadeh., 1910, 31, 493 ; A., ii, 818,A.Wolters, ibid., 5; ; A., ii, 775MINERALOGICAL CHEMISTRY. 229ductivity a t all temperatures without electrolytic conductivity, suchas galena, antimonite, ilmenite, pyrite, magnetite. (B) Crystalswhich are insulators at' the ordinary temperature, but which exhibitmeballic conductivity at rather higher temperatures, for example,blende, molybdenite, fahlerz. (C) Crystals such as cassiterite andchrysoberyl, which probably exhibit both metallic and electrolyticconductivity, but in which polarisation has not been definitelydetermined. (D) Cryst.als which are insulators at the ordinary tem-perature, but become conductors and exhibit polarisation a t hightemperatures. These include barytes, sapphire, many silicates, andmetallic chlorides and iodides.The transition from the amorphousto the crystalline state is usually accompanied by a break in thetemperature-conductivity curve. I n the case of polymorphous sub-stances, the form stable a t high temperatures is the best conductor.C?b emical Crystallography .I n any historical survey of the development of our ideas concern-ing the relation between chemical constitution and crystalline form,the year 1910 must always stand out prominently as associated withtwo important events. I n the first place, the publication of thethird volume of Groth's invaluable Chemisehe Krystallogmphiehas reduced to order and presented in a form convenient for studyall available data concerning crystals of derivatives of the paraffin,olefine, and acetylene series, as well as those of uric acid, theterpenes, and cyclohexane. Secondly, the Barlow-Pope theory hasbeen successfully applied t o the solution of the problems presentedby the aliphatic hydrocarbons, and it has been shown that, so faras the somewhat meagre crystallographic data allow of comparison,the results deduced from the theory are in harmony with thegoniometric observations.l3As is well known, this theory rests on a very few simpleassumptions. I n the first place, each atom of the moleculesunder consideration is believed to possess its own sphere ofinfluence; the spheres of influence of atoms of the same kind areto be regarded as equal in a set of compounds belonging to the sameseries, while the spheres of influence of atoms of different kinds areproportional t o the fundamental valencies of the atoms; thus, thesphere of influence of the carbon atom is four times as great asthat of the hydrogen atom.Secondly, for the purposes of thisdiscussion, these spheres of influence may be represented by meansof incompressible, but def ormable, material spheres of appropriatesizes, piled together in regular order according to the principles ofl3 W. Barlow and W. J. P o p , Trans., 1910, 97, 2308230 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.closest-packing. Now, since the crystalline forms of the hydrecarbons themselves are unknown, the results developed from thetheory can only be tested by means of their halogen or otherderivatives. The halogens are, however, univalent, like hydrogen.Their spheres of influence are therefore, ex hypothesi, approximatelyequal in size to those occupied by hydrogen atoms, and in the closely-packed assemblages of material spheres which represent the variousmolecules, hydrogen spheres ought t o be capable of substitutionby others of about the same size, representing chlorine, bromine, oriodine, without destroying the character of the assemblage.I n thefirst section of the paper before us, it is shown that such anassumption does no violence t o the crystallographic data in caseswhere direct comparison is possible, and that we are thereforejustified in drawing conclusions as to the structure of the hydro-carbons from the study of the morphology of their halogenderivatives.I n the next section, the structure of methane is COG-sidered. Starting with a number of equal spheres representingca-rbon regularly arranged in closest-packing, it is shown how halfthe spheres may be removed in a regular manner, and the intersticesthereby left in the structure may be filled with groups of fourhydrogen spheres, each having one-quarter of the volume of a carbonsphere, so that the whole assemblage remains highly symmetricaland closely packed. This assemblage has not merely the com-position of methane, but is so far in accord with the van’t Hoff-Le Be1 theory that the units into which the whole structure maybe apportioned each consists of a carbon sphere with four hydrogenspheres, arranged round it in such fashion that the centre of eachof the latter lies approximately at the corner of a regular tetra-hedroc.The structure thus arrived at is found t o be in harmonywith the crystalline forms of carbon tetraiodide, carbon tetra-bromide, iodoform, and of tetrabromo-B/3-dimethylpropane. Thestructure of methane once settled, the next problem is to accountfor its normal homdogues. Now, since any normal paraffin may berepresented as H*[CH,],*H, it is desirable, in the first instance, todetermine the structure of the general met hylene assemblage of theempirical composition CH,, for by addition to it of hydrogen spheresin appropriate number and in regular arrangement the structure ofany other normal paraffin can be deduced. A simple method ofconstructing the methylene assemblage is the following.Space isregarded as divided into a series of endless hexagonal prisms; theseare further sub-divided into hexagonal cells by planes perpendiculart o the prism axes, .the height of each cell being equal to its shortestdiameter. I n each cell is placed a sphere representing a carbonatom, and at each cell corner is placed a smaller sphere representinMINERALOGICAL CHEMISTRY, 231the hydragen atom, and touching the six neighbouring carbonapheres. The assemblage, which has the empirical composition CH,,is next adjusted by increasing the diameters of the small spheresuntil their volumes are one-quarter those of the large spheres.After the further adjustment required t o reduce the assemblage,dislocated by the last operation, to the state of closestrpacking, astructure is arrived a t which is in harmony with the stereochemicslfeatures of the chain CH,.From the methylene assemblage thestructure proper to ethane can readily be obtained by insertingpairs of hydrogen spheres in a symmetrical manner. The crystallo-graphic properties of the hexahalogen derivatives of ethane are inaccord with the structure so obtained. I f the adjustment of thehexagonal cell assemblage of empirical composition CH, is carriedout in a slightly different way, an alternative methylene assemblageis attained, which exhibits tetragonal symmetry, and from whichnormal butane may be derived. It is found, moreover, that thecrystallographic properties of the homologues of ethane can readilybe brought into relation with one or other of the methyleneassemblages.To bring the secondary and tertiary paraffins within the scopeof the theory is now a comparatively simple task.Thus, toarrive at tetramethylmethane, we have merely to removesymmetrically every fourth group of four hydrogen spheres froma methane assembla.ge, and replace them by an equivalent carbonatom. This can be done in two ways, the resulting assemblageshaving cubic or tet'ragonal symmetry respectively. The observationthat the crystals of the compound C'(CH,Br), are pseudo-cubicaffords strong confirmation of the validity of this procedure.By removing methylene layers from tetramethylmethane, wearrive a t trimethylmethane, CH(CB,),, and by the reinsertion ofsuch layers in appropriate positions, isopentane, (CH,),CH-CH,*CH,,can be accounted for.The assemblage representing propane canalso be easily derived from that assigned to tetramethylmethane.Now, since the graphic formulae for all the remaining hydrocarbonsof the form Cn€12n+2 can be derived from those of methane, tri-methylmethane, and tetramethylmethane by the insertion ofmethylene groups, and as by a similar process the assemblages properto the various hydrocarbons can be constructed from those whichrepresent the structures of the simpler ones, it follows that thegeometrical method of interpreting molecular structure is inharmony with the facts already summarised in our ordinary chemicalformuh.The structure of the paraffins once established, i t is an easystep to the type of assemblage characteristic of the olefines232 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Starting with the methylene assemblage in its tetragonal form, weremove the small spheres representing hydrogen from one face ofeach of two composite layers, and then key together the faces laidbare.This process is the geometrical representation of the pro-duction of an ethylene linking. On adding to this assemblagehydrogen or halogen spheres in suitable numbers, ethylene or itshalogen derivatives are made. The crystals of the compound C,I,have constants consistent with this structure. On passing next tothe homologues of ethylene, it can be shown that structures corre-sponding with all possible molecules of the formula C,H, can easilybe obtained.Of these molecules there are six. The first three,namely, cis-s-dimethylethylene, trans-s-dimethylethylene, and ethyl-ethylene, can all be derived by applying in different ways to thenormal butane assemblage the process of excising hydrogen, whichled to the production of ethylene. From the isobutane assemblagea fourth arrangement, representing as-dimethylethylene, can beobtained. Another assemblage, that of methyltrimethylene, can beobtained from both butane and from isobutane, and the sixth, thatof tetramethylene, can be made from butane only. Our knowledgeof the crystallography of substances of this kind is lamentablydeficient, and it will be the work of the future to fill in the detailsof the scheme of which the main outlines have now been clearlytraced.Little, too, is known about the crystals of acetylenederivatives, but the structure of acetylene may be arrived at thus.Starting with a closest-packed assemblage of equal carbon spheresof volume four, place in each cavity surrounded by six large spheresa smaller sphere representing hydrogen, and touching each of itslarger neighbours. These small spheres are just as numerous as thelarge ones, but their volumes are less than unity. Let them there-fore expand until their volumes become unity, and adjust thedislocated assemblage so that each large sphere is in contact withone other sphere of its own size, the points of contact of spherewith sphere being distributed through space as evenly as possible.From this assemblage, which represents acetylene, those of allyleneand ethylacetylene can easily be obtained.This simple method ofrepresenting the structure of acetylene is further remarkable inthat by its aid the transformation of acetylene into aromatic hydro-carbons can be accounted for, it being only necessary slightly todistort the acetylene assemblage to bring it into the configurationproper t o benzene. The behaviour of di-iodoacetylene, which, byslight warming or by the action of light, is converted into hexi+iodobenzene, is in accord with this, and certain other similar casesof polymerisation receive the same explanation.No one who carefully studies this paper can fail to be convinceMINERALOGICAL CHEMISTRY.233that it marks a notable advance, and that there is every prospectthat in the cear future the correlation of chemical constitution andcrystal form will proceed rapidly and surely along the lines hereindicated .The validity of the conclusions derived from the Barlow-Popetheory can only be properly tested by means of accurate dataobtained for series of related substances; for the present, at anyrate, isolated observations are of minor value. We will thereforenow consider a few researches of the kind on which future progressdepends. For a number of years past, H. E. Armstrong14 hasbeen accumulating observations on derivatives of benzene. Theinquiry has embraced a wide field, and included chlorides andbromides of the various dihalogen substitution products of benzene-sulphonic acid.Some remarkable relations have been detected, andthe study of a long series of compounds containing two halogenatoms in the par%position has been completed.15 The results ofaccurate measurements made on twenty-nine different derivativesshow that all belong to two crystalline types, one derived from thehexagonal, and the other from the cubic mode of close-packing ofequal spheres. I n each the carbon atoms appear t o be arrangedexactly as in crystalline benzene, and the introduction of sub-stituting atoms or groups merely expands the benzene assemblagein two of the three possible directions, the orthorhombic symmetryof the benzene assemblage being usually lowered in the process.A large number of derivatives of ethylenediamine have beenexamined by M.Frank,16 and some more or less isolated observationshave been published by F. Zambonini17 and by C. Blass.l*Of greater importance is a memoir 19 which has for its object thestudy of the relations between density and refractive index in thecase of a number of crystalline, isomeric or polymeric, organicsubstances ; thus, methyl oxalate has been compared with succinicacid, catechol with resorcinol and quinol, whilst the relations dueto polymerisation have been studied in the case of dicyanodiamide,(CN*NH,),, and melamine, (CN*NH,),. The chief result of thiselaborate investigation is to confirm the validity of the law dis-covered by Landolt from a study of isomeric organic liquids,namely, that the grouping of the atoms in the molecules of met+meric substances has very little influence on the refractivity, andthat therefore the members of a metameric group possess nearlyl4 Tmns., 1910, 97, 1578.l5 R.T. Colgate and E. H. Rodd, ibid.. 1585.l6 Zeitsch. Kyyst. Jfin., 1910, 47, 346 ; A . , i, 302.l7 Ibid., 620 ; A . , ii, 610.I* Ibid., 48, 20 ; A., i, 614.l9 K. Heydrich, ibid., 48, 243 ; A., i, 705234 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the same specific refractivity. Further, it would appear that thevariations in specific refractivity occurring in the case of polymericsubstances are much greater than those observed in the case ofmetamerides, the denser substance having always the smaller specificrefractivity. The application of this law to minerals indicates thatcalcite and aragonite are polymerides, but that the three varietiesof titanium dioxide are metameric, while of the three silicates ofthe formula Al,SiO,, andalusite and cyanite are to be regardedas metamerides, but fibrolite is a polymeric form.It has furtherbeen found that intimate morphotropic relations exist between thetwo dinitrotoluenes (CH,: NO2: NO2= 1 : 2 : 4 and 1 : 2 : 6) andbetween dicyanodiamide and melamine, whilst the two compounds,C,H,(OH)*S0,K,2H20 (OH : S0,K = 1 : 2) and C,H,(OH)*SO,K(OH : SO,K= 1 : 4), curiously enough, exhibit the same opticalrelations ils normal position isomerides.The relations between thallium and the alkali metals have beenfurther elucidated by A.E. H. TuttonFO who has subjected thedouble sulphate and selenate of thallium and zinc to crystallographicand optical examination in his accustomed thorough manner. Hefinds that the properties of these salts justify their inclusion in theisomorphous series of the type but that tbe ymust not be brought into the more exclusive eutropic series withinthe isomorphous group.Some interesting observations on the crystallography of themercury halides have been published by 5. S. van Nest.21 Mercuricchloride, he finds, is dimorphous, possessing two orthorhombicmodifications, the first proper t o the pure salt, the second a formisomorphous with that of mercuric bromide. The chloride andbromide form an interrupted mixed series, and a double saltprobably exists.The bromide is trimorphous, for in addition toentering into mixed crystals of the form of the chloride, it willalso crystallise with the red tetragonal form of the iodide. Likethe chloride, the latter is dimorphous, being isomorphous in itsyellow form with the orthorhombic bromide.The position of silicon in the periodic classification is such asto suggest the existence of analogies between the crystal forms ofcompounds of silicon and of carbon. Compounds of the twoelements of analogous composition are, however, very different inform, and G. Jerusalem 22 has sought to explain the discrepancy inthe light of the Barlow-Pope theory by the suggestion that, whereasthe fundamental valency of carbon is four, that of silicon is but*O Proc. Xoy.h’oc., 1910, 83, A, 211 ; A . , ii, 127.a1 ZeLitsch. Kryd. Min., 1910, 47, 263; A., ii, 295,Tmns.61910, 97, 2190MINERALOGICAL CHEMISTRY. 235two. He has shown that the morphotropic relations existing betweensilicon and carbon compounds, such as (C6H5*CH,),Si*OH and(C6H5*CH2)3C*OH, can be readily accounted for on this hypothesis.I n concluding this section, we may call attention to some remark-able observations which have recently been made on the crystals ofpotassium silicotungstate. It has, up to the present, been generallybelieved that the two enantiomorphous forms assumed by substances,such as quartz and sodium chlorate, are dike in everything savein the sign of the rotation produced in the pla.ne of polarisation oflight traversing the crystals.There appear, however, to beindications of the existence of more profound differences. Thus, ithas been known for some time that potassium silicotungst,atecrystallised from aqueous solution almost invariably appears in theright-handed form. This curious fact has not only been verifiedby H. C0paux,2~ but he has also shown that, although the left-handed form can be obtained, it is produced more slowly anddissolves more rapidly than its enantiomorph. When sodiumchlorate was examined, it was found, contrary to the observationsof previous experimenters, that there was a tendency for right-handed crystals to preponderate, and the velocity of growth ofthese appears to be distinctly greater than is the case with left-handed crystals.Hence he concludes that the two enantiomorphousforms exhibited by such substances are not to be consideredidentical, but rather as dimorphous, and it is therefore conceivablethat a substance might exist exhibiting rotatory power, butinvariably appearing in one form, the other being quite unstable.These observations and the conclusions based on them have alsobeen discussed by E. Sommerfeldt.24New Minerals.Alternousit e, Barbiem’te, Garnegieite.-As these three names havebeen applied by American investigators to different varieties offelspar, it will be convenient to consider them together. Anemousiteis found in large, clear crystals, well suited for chemical and opticaldetermination, in the basaltic lava of the island of Linosa, and hasbeen the subject of a most careful examination by H.S. Washingtonand F. E. Wright.25 The physical characters of the mineral indicatea plagioclase, Ab,An, to Ab,An,, but the results of analyses cannotbe explained by any mixture of albite and anorthite, though theyare expressed pretty accurately by the formula,Na,0,2Ca0,3A1,0,,9Si02 or (&Na2,~Ca)A12Si,0,,,part (about 1/12) of the sodium being replaced by potassium.2y Bull. Soc..fmnq. itfin., 1910, 33, 162; d., ii, 301,24 Tsch. Mi%. Nitt., 1910, 29, 353.as Amer. J. Sci., 1910, [Iv], 29, 52.T236 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,explain this discrepancy, Washington and Wright assume theexistence of a aodacanorthite molecule, Na&12Si20,, and show thatthe composition and properties of the Linosa felspar can be satis-factorily accounted for if it be regarded as a mixture of albite,anorthite, and sodilranorthite in about the proportions 8: 10: 1.This peculiar felspar they propose to call anemousite, from the oldGreek name of the island of Linosa, whilst for sodsanorthitethey suggest the name carnegieite, for although present in butsmall proportion in anemousite, it has been prepared artificially inthe Geophysical Laboratory at Washington, and its individuality,as a, triclinic felspar allied to anorthite, satisfactorily established.The existence of a monoclinic felspar, NaA1Si30s, isomorphous withorthoclase and dimorphous with albite, appears also to have beendemonstrated, largely owing to the analytical work of P.BarbierF6and the name barbierite has therefore been suggested for thisThe felspar from Kragerij, containing but 1.15 per cent.of K,O, is almost pure barbierite, and a soda-sanidine fromMitrowitza consists approximately of equal parts of orthoclase andbarbierite.28 It occurs in large, monoclinic crystals, the cleavageangle, PM, being 90°1 . The extinction on P is Oo, and on M, 2O52'.The optic axial plane is perpendicular to the plane of symmetry,and an acute negative bisectrix emerges through P. 2E = 37O55'.The composition may be expressed as 8KA1Si,08 + 9NaA1Si30,.Cobaltocalcite.-A red variety of calcite occurs at Capo Calamita,Elba.29 It is denser and harder than ordinary calcite, and contains2 per cent. of cobalt carbonate.Gageit e.-A new mineral occurring in delicate, colourless, acicularcrystals has been found at Franklin, New Jersey, associated withcalcite, zincite, willemite, and leucophoenicite.30 An analysis madeon 0.04 gram shows that it is a hydrated silicate of manganese,magnesium, and zinc of the general formula 8R0,3SiO2,2H,O.Itis therefore closely related to the leucophaenicite on which it isimplanted, and probably shares with it a common origin.GoZdfieldite.-At the Mohawk mine in the goldfield mining dis-trict of Nievada, some gray material has been met with, which isbelieved fo be a cupric sulphantimonite, in which part of theantimony is replaced by arsenic and bismuth, and much of thesulphur by tellurium.315CuS,( Sb,Bi,As),( S,Te),,The formula assigned is26 See Ann.Beport, 1909, 211.27 W. T. Schaller, Arner. J. Sci., 1910, [iv], 30, 358 ; A., ii, 1078.28 F. Angel, Jahrb. Min. Beil.-Bd., 1910, 30, 254 ; A., ii, 783.29 F. Millosevich, Atti li. Accnd. Liacei, 1910, [v], 19, i, 91 ; A . , ii, 22130 A. H. Phillips, Amer. J. Sci., 1910, [iv], 30, 283 ; A., ii, 968.31 F. L. Rausome, United Xtatcs Geol. Xurv., Prof. paper, No. 66MISERALOGICAL CHEMISTRY. 237but as the analysis shows a very high summation, and was madeon a small quantity of the substance, which exhibited no crystallineform, the individuality of the species can hardly be considered asestablished beyond question.Joap&zite.-This name has been proposed for minute o r t h erhombic crystals found in the natrolite vein in which benitoiteoccurs in California.The crystals are honey-yellow or light brownin colour, and contain silica, titanium, calcium, and iron, but theyhave not as yet been completely determined.32Minguetite.-Opaque black or greenish-black plates occur inaggregates associated with chalybite, quartz, and some galena in avein at the junction of beds of magnetite with an altered diorite inthe Minguet mine, near Segr6, France.33 The substance wasformerly believed to be biotite, but on analysis was found to containtoo little alumina and alkalis, and to give up its water too easily.The formula, 17Si02,4(Fe,A1)203,8(Fe,Mg)0,K20,8H20, indicatesthat in composition the mineral is intermediate between the mica,lepidomelane, and the chlorite, stilpnomelane.Hosesite.-In these reports for 1906 and 1907, attention wasdirected to the remarkable mercury minerals found at Terlingua,Texas, and the discovery of another member of the series has nowto be recorded.34 The new mineral, for which the name mosesitehas been proposed, somewhat resembles kleinite, being apparentlya mercury ammonium compound containing chlorine and sulphate,the mercury being probably in the mercurous condition.It occurson calcite in minute, regular octahedra or in spinel-twins. Thecrystals are canary-yellow in colour, and birefringent. On haatingto 186O, they become isotropic, but revert slowly to the birefringentcondition on cooling.PiZbarite.-A bright yellow, ochreous mineral occurs in a tantalitelode a t Wodgina, Pilbara Goldfield, Western Australia.34a It isamorphous, and probably a hydrous pseudomorph.The com-position is approximately expressed by the formula :Pb0,U03,Th0,,2Si0,,2H,0'+ 2H20.Quercyite.-A study of the mineralogical constitution of theFrench phosphorites has led A. Lacroix 35 to suggest a new nomen-clature for these substances. Isotropic compounds of calciumphosphate and carbonate are classed as colophanites, whilst mixturesii, 310.33 G. D. Louderback, Bull. Dept. GeoE. Univ. Califomin, 1909, 5, 331 ; A.,33 A. Lacroix, BuEE. Soc franc. Jlin., 1910, 33, 2TO; A., ii, 783.34 F. A. Canfield, W. F. Hillcbrand, a i d W. T. Schaller, Amer. J. Sci,, 1910,30a E. S. Simpson, Chem. News, 1910, 102, 283.80 Corn& rend., 1910, GO, 1213 ; A,, ii, 720.[iv], 30, 202 ; A , , ii, 965238 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,of colophanite with optically negative crystalline matter of similarcomposition are termed quercyite.Sometimes the crystalline mattermixed with the colophanite is partly positive, partly negative. I nthis case the mixture is termed P-yuercyite.Samso&e.-Steel-grey, monoclinic crystals, which resemblemiargyrite in appearance, have been found a t the Samson mine,St. Andreasberg, associated with pyrargyrite, galena, pyrolusite,etc.S6flew Vanadut e.-A vanadate, somewhat resembling cupro-descloizite in composition, has been observed in the cupriferousdeposits of Bena (d)e Padru, near Ozieri, Sardinia.37WiZtshireite.-This name has been assigned by W. J.Lewis 38 toa mineral found in the dolomite of the Binnenthal, where it occursin small, monoclinic crystals having a somewhat characteristiclustre and the following crystallographic consta.nts : a : b : c =1.587: 1 : 1.070, P=79O16/. The chemical composition has notyet been determined owing to paucity of material, but* theindividuality of the species is inferred from the crystallographiccharacters. The same substance appears t o have been noted byR. H. Solly38a in 1903, and is referred to under the title ofrathite a in the list of minerals from Binn given by L. Desbuissonsin his book, La ValZte de Binn.On analysis, the formula was found to be 2Ag2S,MnS,Sb2S3.Mineral Analyses.Adamite.-Pure material from Thasos, Turkey, has a compositionagreeing very closely with the usual formula, Z~,AS,O,,Z~(OH)~.~~The axial ratios of the orthorhombic crystals are a : b : c =0.9764: 1 : 0.7049.A kcandrite.-This variety of chrysoberyl possesses the remark-able property of appearing dark green in daylight, but cherry-redin artificial light.It has been found that solutions of chromiumsulphate which have been gently boiled exhibit the same phenomena,and i t seems probable that the peculiar properties of the gem aredue to the presence of chroniium oxide, partly in colloidal solidsolution, and partly in isomorphous adrni~ture.~OAZstonite.-The occurrence of this rare mineral has been reportedfrom the New Brancepeth Colliery, near Durham, where it is foundassociated with barytes and witherite in a fault-vein intersectingD. Lovisato, Atli A.Accad. Lincei, 1910. [v], 19, ii, 326 ; A., ii, 1077.36 Werner and Fx-aaty, Centr. Jfin., 1910, 331 ; A . , ii, 620.33 Phil. illag., 1910, [vi], 20, 474.38a Nature, 1903, 69, 142.V. Rosicky’, Bull. Intern. Acad. Sci. Bohdme, 1909, 13, 21 ; A., ii, 309.0. Hauser, Zeitsch. angew. Chern., 1910, 23, 1464 ; A,, ii, 873MlKERALOGJCAL CHEMISTRY. 239the coal measures.41 An analysis agrees approximately with theformula BaCa(CO,),.Amphibole G?-oup.-X. Galkin 42 has analysed seven specimens ofhornblende crystals from different localities in the Rhon Mountains.The composition is nearly the same in each case, the mean valuesbeing as follows :30,. TiO,. P,O,. A1,0,. Fe,O,. FeO. MgO. CaO. Na,O. K20. IT,O40'65 3.76 0'88 13.87 8'36 4.57 12-34 12.23 2-27 1.14 0.45The part played by the titanium and the general relation of theseresults to the views as to the composition of hornblende held byTschermak, Scharizer, Rosenbusch, and Penfield are discussed atlength, but no very definite conclusions are reached.AntZerite.-A basic copper sulphate, 3CuS04,7Cu(OH),, wasdescribed under this name by Hillebrand in 1889. Ten years laterthe name stelznerite was assigned by Arzruni and Thaddeeffto a mineral from Chili, for which they found the formulaCUSO,,ZCU(OH)~.Optical examination of the type specimen ofantlerite and comparison of its composition with that of stelzneritehas convinced W. T. Schaller 43 that the two substances are identical,and that the formula assigned to stelznerite is correct.He proposes,however, to abandon the latter name, in view of the prior use of theterm antlerite.ApophyZZite.-Pure material from the Radauthal, Harz Moun-tains, has approximately the formula 4C~H,Si3Ol1,K2H,Si,Ol,.The specimen is remarkable in that it appears to contains alumina(1.78 per cent.) as an essential c o n s t i t ~ e n t . ~ ~Arse.nopyrite.-Brilliant crystals from Franklin Furnace, NewJersey, have it composition accurately expressed by the formulaFeAsS, part of the iron being replaced by 1-16 per cent. of cobalt.459 tacamite.-The composition of remarkable twinned crystals fromCollahurasi, Chili, was found on analysis to agree very closely withthe formula C ~ C ~ , , ~ C U ~ O H ) , . ~ ~Axinite.-A specimen from the Radauthal47 is nearly puremanganese axinite of the formula HMnC+BA1,Si40,,, and agreeswith the general formula HR11R112BA1,Si40,6 proposed by Rammels-berg for the mineral from Bourg d'Oisans.The same generalformula covers the case of crystals from Moosa Caiion, San DiegoCounty, California, for which the composition8 Si02,2A120,,2 (Fe,Mn,Mg)0,4Ca0,H20,B20,Sp. gr = 3-67.41 L. J. Spencer, Min, Mag., 1910, 15, 302; A . , ii, 307.48 Jahrb, Nin, Beil,-Bd., 1910, 29, 681 ; A., ii, 721.43 Amer, J. Sci,, 1910, [iv], 30, 311 ; A., ii, 1076.44 J. Fromme, Tsch. Min. Mitt., 1909, 28, 305 ; A , , ii, 314.45 C. Palache, Amer. J. Sci., 1910, [iv], 29, 177 ; A . , ii, 219.47 J. Fromme, Tsch. Mim, ilfitt., 1909, 28, 305 ; A., ii, 314,W.E. Ford, ibid., 30, 16240 ANNUAL REPORTS ON TEE PROGRESS OF CHEMISTRY.hae been found by W. T. Schaller.48 From the consideration ofother analyses, he has been led to suggest that the atomic pro-portion of calcium is constant, and that manganese and ferrousiron replace one another isomorphously, the mineral being regardedas an isomorphous mixture of ferroaxinite, HFeCa,BAl,Si,O,,, andmanganoaxinite, HMnC~BA12Si40,,. Small, transparent crystalsfrom the Consumes copper mine in Amador County also affordedresults in harmony with these conclusions.Baddeleyite. -This mineral occurs in some quantity in Brazil,and its composition has been investigated by E. Wedekind,49 andalso by L. Weiss and R. Lehmann.50 From this work it appearsthat the Brazilian specimens consist in the main of dioxide ofzirconium, together with small amounts of ferric oxide, alumina,silica, and water.The zirconiaseparated from large quantities of the material was submitted toan elaborate process of fractionation by Weiss and Lehmann, butno indications of resolution into two or more oxides could beobserved. Similar results were obtained by 0. Hauser and F.Wirth,51 who fractionated the zirconia prepared from a number ofminerals to see if they could find any evidence for the existence of thesecalled euxenium earth of Hofmann and Prandtl.52 The resultswere negative.BarytoceZestine.-The mineral described under this name fromthe Binnenthal has been shown to be pure barytes.53 Baryto-celestine does not appear to exist in distinct crystals, and thespecimens from other localities are probably mixtures.Bementite.-The occurrence of this mineral at Franklin Furnace,New Jersey, has enabled a fresh investigation of its characters t obe made.54 It crystallises in the orthorhombic system, has theformula H,Mn,(SiO,),, and is closely related to tephroite.Bertrarndite.-Crystals of this rare mineral resulting from theweathering of beryl occur in the Altai Mountains.55 The com-position is represented by the formula H,Gl,Si,O,, although theamount of glucinum found is rather low.Bery2.-The composition of pink beryls from Madagascar andfrom Mesa Grande and Pala, both in San Diego County, California,has been studied by W.E. F0rd,~6 who has compared their opticalTraces of titanium are also present.48 Zeitsch.Kryst. Min., 1910, 48, 148 ; A , ii, 874.49 Bcr., 1910, 43, 290 ; A., ii, 218.51 Ber., 1910, M, 1807 ; A., ii, 713.53 V. Xosickf, Bull. Intern. Acad. Sci..Eoh&rne, 1909, 13, 21 : A., ii, 309.64 C. Palache, Amer. J. Sci., 1910, [iv], 29, 182 ; A., ii, 219.66 P. P. Pilipenko, Bull. h a d . Sci. St. Pdtersbourg, 1909, 1116 ; A . , ii, 48.MJ Amer. J, Sci., 1910, [iv], 30, 128; A , , ii, 873,Zeitsch. anorg. Chem., 1909, 65, 178; A., ii, 133.52 Ibid., 1901, 34, 1064 ; A . , 1901, ii, 3SMINERALOGICAL CHEMISTRY. 241properties with those of beryls rich in alkalis from Willimantic,Conn., and from Hebron, Maine, analysed by Penfield and byWells. It is found that as the glucina is replaced by alkalis thereis an increase in the values of the refractive indices, birefringence,and specific gravity, as exhibited in the following table :Locality.W . c. Sp. gr. Li20. Na20. K20. Cs,O.Mesa Grande ... 1-58157 - 2.714 0'46 0.84 0'18 -Willim~ntic ..... 158455 1.57835 2.730 0.28 0.75 0'12 -Pala ............... 1'59239 1.58488 3.i85 1-33 1'59 0'28 0.57Hebron .......... 1'59824 1.59014 2.800 1-60 1'13 - 3.60Lacroix57 has pointed out that the beryls rich in cesium fromMadagascar are similar to those from the Ural Mountains recentlydescribed by Vernadsky under the name vorobyevite.58 The berylsof Madagascar have also been the subject of a somewhat elaborateinvestigation by L. Duparc and his assistants,a who have obtainedthe following values for the indices of refraction and specificgravities :Madagascar ...... 1.59500 1.58691 2 790 1 68 1.60 - 1 *70Locality.Colour. Sp. gr. W . €.Tsilaisina ............... piiilr 2.7165 1.5830 15747Tsaravovona ............ 27027 1.5782 1 % i 2 5Antabolro ............... bihe 2.7477 15897 1.5819Tetehina.. ............... , , 2.7116 1.5818 7 *.574sAmbatolam py ,, 27192 1.5838 1'5752Tongafeno .............. , , 2.7379 1.5849 1'5771The composition of the crystals from Tsilaisina was as follows:SiO,. 40,. GIO. bInO. Li,O. Na,O. K,O. H,O.64-76 18'14 13.76 0.003 0'04 0.73 0'15 2-24P. Barbier and F. Gonnard6O have found that beryls frompegmatite near Biauchaud, Puy-de-DGme, and from Montjeu can berepresented by the formula H2Gl,Rl4Si,,O3,.Bismite occurs as the result of the oxidation of bismuth sulphidein colourless scales a t several mines in Nevada.61 The scales areof hexagonal outline, and possess basal cleavage.They exhibit anegative uniaxial interference figure, and probably belong to therhombohedra1 system. Analysis of material mixed with muchgangue indicates that the substance is either bismite, Bi,O,, orhydrous bismuth oxide.Bityite.-The following revised formula has been assigned to thisrare mineral 62 :.........2 1 SiO,, 1 6A1,03,14 (Ca,Gl,Mg)0,4 (Li,Na,M),O, 14H20.6357 Bull. SOC. franc. Milt., 1910, 33, 44 ; A . , ii, 307.58 See Ann. Report, 1909, 228.59 Bull. SOC. franq. Min., 1910, 33, 53 ; A . , ii, 312.6o Ibid., 74, 78 ; A., ii, 418.61 W. T. Schaller and F.L. Ransome, Amer. J. ,S'ci., 1910, [iv], 29, 173 ; A., ii,w3 Compare Ann. Report, 1909, 222.220. 62 A. Lacroix, Bull. Soc. franc. Min., 1910, 33, 52 ; A . , ii, 307.REP.-VOL. VII. 242 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Rrociiantite.-The composition of good crystals from Collahurasi,Chili, is accurdtely represented by the formula. C U S O ~ , ~ C U ( O H ) ~ . ~ ~Broggem'fe.-The composition of iron-black radioactive crystalsfrom Borneo may be represented as:4 SiO,,45UO3,48U0,,1 2Pb0,6ThO2,2Y,O,,Ca0,4Fe0,9Hz0.65Carnotite.-An investigation of the yellow powder occurring increvices in an intimate mixture of ilmenite, rutile, and magnetiteat Radium Hill, South Australia, has led t o the conclusion thatthis substance is a definite mineral species, essentially a hydratedvanadate of uranium and potassium.66 The minute orthorhombicplates have a good basal cleavage, perpendicular to which an acutenegative bisectrix emerges.Incidentally it has been shown thatthe matrix in which the carnotite is found, and t o which the namesdavidite and sefstromite have been applied, is a mixture.Cordi'erite.-Fragments of this mineral from the micaceousquartzite of the Ibity Mountains, Madagascar, have the followingcomposition 67SiO,. A1,0,. Fe,O,. FeO. MgO. ign. Total. Sp. fir.49-05 33.08 0.83 4-38 11'04 1'64 100'02 2.5933The refractive indices are a = 1.53958, P = 1.54516, y = 1.54853.CqmkZine.-This interesting species, hitherto only recorded fromVesuvius, occurs also at Franklin Furnace, New Jersey, for whitecrystal fragments from the Parker Shaft were found on analysisto have the formula Ca2Si(0,F2)4.68DcahZZite.-A mineral exhibiting the characteristic scroll structurediscovered in calcedonite by LBvy, and imitated by Wallerant inorganic compounds by melting them in the presence of opticallyactive substances, occurs in the phosphorites of M o ~ i l l a c .~ ~ Thecomposition of the substance is practically identical with that ofdahllite, 2C~P20,,CaC0,,~Hi0, of which it appears to be a variety,This is probably also true of a substance called podolite,70 mentionedamong the new minerals in the annual report for 1907.DatoZite.-Good crystals of this mineral occur at the junction ofa serpentine with a hornblende-schist at Park Bean Cove, Mullion,Comwall.71 The analytical results agree very closely with thoseW.E. Ford, Amer. J. Sci., 1910, [iv], 30, 24.65 G. P. Tschernik, Bull. Acatl. Sci. St. Pkters3ozwg, 1909, [vi], 3, 1203 ; A., ii,136.T. Crook and G. S. Blake, Min. Mag., 1910, 15, 271 ; A . , ii, 308.67 L. Duparc, R. Sabot, and M. Wunder, Arch. Sci. phys. nut., 1910, [iv], 29,68 C. Palache, .Amer. J. Xci., 1910, [iv], 29, 185; A., ii, 219.69 A. Lacroix, Compt. rend., 1910, 150, 1388; A., ii, 622.7O W. T. Schaller, Amer. J. Sci., 1910, [iv], 30, 309 ; A., ii, 1076.W. F. P. McLintock, Min. Mag., 1910, 15, 407; A . , ii, 78262 ; A., ii, 221MINERALOGICAL CHEMISTRY. 243required by the usual formula, HCaBSiO,. The sp. gr. is 3.001,and the optical constants as follows : a = 1.626, p = 1.653, y = 1.670.2Va= 76O16’ (sodium light).The optic axial plane is 010, and theacute bisectrix almost perpendicular to 100.Dawsonite.-Crystals of this very rare mineral have been foundto have the composition Na,0,A1,0,,2C0,,2H20.7~ They belong tothe orthorhombic system, a : b : c = 0.6475 : 1 : 0.5339.Ep*dote.-A number of minerals collected by the Duke of theAbruzzi’s expedition to Ruwenzori have been described by L.Colomba,73 and analyses made of some, including three specimens ofepidote. For two of these, the ratio SiO,: R203:.(R0,R20) is2 : 1 : 2; in the third, 10 : 5 : 9.Euccemife.-Specimens from Eitland and from Arendal provedon analysis to be typical euxenites.74 A third from Saetersdalmust be classed as polycrase, whilst a specimen from South Carolinawas found to contain more tantalic acid and less titanium thanis usually present.Zirconium could not be detected in any of thesamples. An analysis of a euxenite from Cooglegong, WesternAustralia, has also been published.75FahZerz.-An important contribution to our knowledge of thismineral has been made by A. Kret~chmer,7~ who has not onlyrecalculated the atomic ratios of 162 published analyses, but hashimself examined specimens from fifteen different localities. Thecarefully selected material was decomposed by bromine, which wasfound preferable to chlorine, and the analyses were carried outwith all precautions. The results are tabulated in the followingform, which summarises the data obtained for a specimen fromHorhausen : (Cu,.47,Zn,.,,),.98SbS3.19. His determinations lead’ himto the conclusion that the ratio Cu+ Zn : Sb is constant and equalto three, whereas the ratio Cu: Zn is variable.He finds that anempirical formula of the type (M’s,M”y),M”/S,+,e expressesthe experimental results, when M/=Cu and Ag, M”=Zn,Fe,Pb,Hg,Mn,Ni, and MI// = Sb,As,Bi. As regards the furtherinterpretation of the results, Kretschmer points out that the formulaof Prior and Spencei-, 3R’,S*R/’/2S, + z6R//S*R’//,S3, is in harmonywith his own determinations, but as it involves the assumption ofisomorphism between compounds of the type Cu,Sb,S, and of thetype Zn6Sb2S,, the part played by cU6s3 in the one being taken byZn6S6 in the other, he prefers t o consider fahlerz as an isomorphousmixture of a zinc compound, Zn,Sb,S,, with a copper compound,72 R.P. D. Graham, Trans. Xoy. Soc. Canada, 1908, [iii], 2, iv, 165 ; d., ii, 136,73 ‘ I II Rzswenzori,”~ZItheD~cn dcgli Abruzzi, Milano, 1909, 2, 281 ; A., ii, 967.74 0. Hauser and F. Wirth, Ber., 1909, 42, 4443 ; A., ii, 47.75 E. S . Simpson, Austrat. AS.QOC. Report, 1909, 310 ; A., ii, 1077.‘13 Zcitsch. Kryst. Min., 1910, 48, 484.R 244 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Cu,Sb,S,, the two equivalent atomic groups being Zn,Sb, andCu,Sb,. The comFosition of fahlerz can then be satisfactorilyrepresented as zCu,Sb,S, + Zn,Sb2Sg. The value of x varies from2 to 10, and is most frequently 3 to 4.Felspar Group-Many members of this group have beenexamined during the past year, and we may direct attention to theseries of analyses of French felspars published by Barbier andGonnard.77 Interest also attaches to the large aggregates whichoccur in the basalt of the Crookdene dyke, Northumberland, whichhave proved to be anorthite,78 and in particular to the labradoritefrom the Altai Mountains in Mexico.79 The latter material is par-ticularly well suited for chemical and optical investigation, and isfound in perfectly clear and almost colourless water-worn pebbles.It has been shown by Ford and Bradley to consist of albite andanorthite in the ratio 1: 1.918.The sp. gr. is 2.718, the anglebetween the cleavages 85O49/, the angle of extinction on 010 is- 24O371, and on 001 is - 12O13'.Friedelite.-There is considerable uncertainty as to the formulawhich best expresses the composition of this rather rare mineral.The formula commonly adopted, H7(MnC1)MnaSi4016, demands lessmanganese and more chlorine than are commonly present.Palache 80has found that Hg(MnC1)Mn7Si,O2, represents fairly satisfactorilythe composition of a specimen from Franklin Furnace, though morewater was observed than this fomiula requires. The mineral hasalso been discovered in some quantity associated with rhodocrositeat Veitsch, in Styria.81 Two analyses have been interpreted byHofmann and Slavik as leading to the formuke (H,Cl)8R7Si,021 and( H,C1),R8Si,0, respectively, where R is chiefly Mn with smallquantities of Ca and Mg. The chlorine content of this material isconsiderably below the average, and it may possibly have undergonea1 t er ation.Ferywo&e.-The composition of a specimen from Cooglegong,Western Australia, agrees with the usually accepted formula,R20,,T%0,.82Garnet Group.-A number of members of this family have beenanalysed during the year.Worthy of note are the analyses of redgarnets from diamond pipes in Rhodesia published by F. P.Mennell,83 and the data for a spessartite from Madagascar given77 Bull. SOC. fruit?. Min., 1910, 33, 81 ; A., ii, 419.M. I(. Heslopand J. A. Smythe, Quart. Joicm. Geol. SOC., 1910, 66, 1 ; A.,ii, 313. 79 Amer. J. Sci., 1910, [iv], 30, 151 ; A , , ii, 874.so Ibid., 29, 183 ; A., ii, 220.a2 E. S. Simpson, Azutral. Assoc. Bryort, 1909, 310 ; A., ii, 1077.83 Quart.J. Geol. SOE., 1910, 66, 353; A . , ii, 1078.Bull. Intsrn. Acad. Sci. Boh&mc, 1909 ; A., ii, 311MTNERALOGICAL CHEMISTRY. 245by L. Duparc 84 and his assistants. This mineral is of gem quality.Its composition is well expressed by the formula Mn,Al,( SiO,),,small quantities of ferric oxide and of lime being present. Theindex of refraction is 1.7998 (sodium light). Sp. gr. 4'0586. Acalcium iron garnet from Praborna, St. Marce1,85 containing 7.81per cent. of chromium oxide, has been examined by L. Colomba,who assigns it t o the variety uvarovite.GZauconite.-Submarine deposits containing glauconite, digestedfirst with hydrochloric acid and then with sodium hydroxide, yield,on shaking with boiling water, a colloidal suspension of disintegratedglauconite, from which, on addition of a trace of acid, a green,flocculent precipitate separates.The precipitate separated by thisprocess from material dredged off Panama and from the AgulhasBank agrees fairly well with the formula KFeSi,0,,H,0.86 Micro-scopic study of glauconite grains suggests that the silicate iscolloidal, and enclosed in a network of organic matter, t.hebirefringence and pleochroism being probably the result of strain.Grass-green, flocculent particles, resembling glauconite, have beenobtained by heating under pressure to 180° the clear, greenish-bluejelly which results when potassium silicate and potassio-ferrictartrate are mixed.Gmhamite.-The relations existing between the various types ofasphalts and bitumens have been discussed by C.Ri~hardson,8~ whosuggests that the term grahamite should be confined to nativebitumen characterised by a schistose or hackly fracture, sparingsolubility in naphtha, and by a high percentage of residual coke.He has tabulated the occurrences of grahamites in America, anddraws attention t o the presence of vanadium in the ash of thesesubstances.Hambergik-This rare mineral has been found in Mad%gascar.88 Analysis of crystalline material leads to the formula4G10,B,0,,H20.HetoeroZite.-A black mineral, supposed to be a zinc hausmannite,was described under this name in 1877. This view of its naturehas now been confirmed by analysis of a specimen from FranklinFurnace, New Jersey, which establishes the formula as Zn0,Mn203.89It crystallises in the tetragonal system.HuZsite.-When first described, this mineral was believed tocontain 25-27 per cent.of BiO,, and to have the compositionArch. Sci. phys. nat., 1910, [iv], 29, 62 ; A . , ii, 221.85 Atti R. Accad. Lincei, 1910, [v], 19, ii, 146 ; A . , ii, 968.s8 W. A. Caspari, Proc. Roy. Soc. Edi~t., 1910, 30, 364 ; A . , ii, 722.p7 J. Amer. Chem. SOC., 1910, 32, 1032 ; A., ii, 964.88 A. Lacroix, B d l . Soc. franc. Min., 1910, 33, 49 ; A . , ii, 307.89 C. Palsche, Anwr, J. Sci., 1910, [iv], 29, 180 ; A,, ii, 219246 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.7(Fe,Mg)0,Fe20,,H20,4B~O~.go A re-determination of the borongives a much lower result, and it has been found that the mineralcontains considerable quantities of tin overlooked in the firstanalysis.g1 The formula now regarded as most probable is12 ( Fe,Mg)0,2Fe20,,Sn02,3B~03,2Hz0.Hu.mlioldtine.-Crystals of this rare mineral have been observedin a vein containing iron and mangaaese a t Cape d'Arco, Elba, andhave been fully described under the name oxalite by E.Mana~se.~2It occurs in minute, orthorhombic prisms associated with the basalpinakoid. The composition is FeC20,,2H20, a simpler formula thanhas hitherto been assigned to the mineral. The crystals are amber-yellow in colour, pleochroic, and strongly birefringent. The indicesof refraction by the immersion method are p=1*561, y=1*692;a could not be determined, but is less than 1.494. It seems likelythat the mineral has resulted from the interaction of oxalic acid,or of an alkaline oxalate of organic origin with ferrous sulphatoproduced by the oxidation of marcasite.Hydrogiob ertite.-Analysis of the spherulitic material whichoccurs in some abundance in the Chiles Valley, Napa County,California, agrees with the formula 2Mg0,C0z,3H20.93ZxioZite.-To this species has been assigned a mineral fromWodgina, Western Australia, of the formula 3Mn0,3T%0,,SnO2.94Jarosite Group.-At Saint-FBlix-de-Pallsres, Gard, France, amineral occurs in ochre-yellow, compact masses, consisting of minutecrystals.It owes its origin to the action of the products of theoxidation of iron-pyrites on the gangue, and was described underthe name pastreite in 1866. A new analysis95 has revealed thepresence of alkalis, and shows that the substance is jarosite,K2Fe6(0H)12(S04)4.PZumbojarosite has been reported from American Fork, Utah.The minute, rhombohedra1 crystals have much the same compositionas the material from New Mexico described by Penfield, and can berepresented by the same formula, PbFe,(OH),,(S04)4.96 Thecrystals are brownish-red in colour, and exhibit the base and thefundamental rhombohedron. The refractive indices are high, E beingabout 1.785, and o )1*825.KaoZinite.-Much attention has been devoted of late to the studyof clays, kaolin, and laterites, and a noteworthy contribution to our90 See An?&. Report, 1909, 224.92 Atti R.Aczad. Lime4 1910, [v], 19, ii, 138; A., ii, 967.9s It, C .Wells, Amer. J. Sci., 1910, [iv], 30, 189 ; A., ii, 965.a E. S. Simpson, Aztstral, Assoc. Report, 1909, 310; A., ii, 1077.95 Az6ma, H u l l . SOC. f r a y . Min., 1910, 33, 130 ; A., ii, 720.96 W. F. Hillebraiid and F. E. Wright,'Amer. J. Sci., 1910, [iv], 30, 191 ; A.,91 W. T. Schaller, ibid., 543 ; A., ii, 621.ii, 966MINERALOOICAL CII EMISTR Y, 247knowledge of these substances has been made by J. M. vanBemmelen.97 Clay, the product of the weathering of silicate rocks,consists, he thinks, of a mixture of crystalline particles of unalteredsilica.tes with a colloidal substance, the result of chemical alteration.The latter contains a silicate resembling kaolir,, having from 2 to2.7 molecules of silica to 1 molecule of alumina, together with afusible silicate whose composition ranges from 2.9 to 6 moleculesof silica to 1 of alumina in the case of heavy clays, and withinsomewhat narrower limits in the case of light clays.Volcanic claysare rich in the fusible silicate, older clays containing increasingquantities of the other. Kaolinite and zeolites appear to be dueto the prolonged action on clay of high temperatures or hot water.Laterite is found in association with both acid and basic rocks intemperate climates as well as in the tropics, and in some cases bothlateritic and ordinary weathering proceed simultaneously. Theresult of lateritic alteration is a product in which the silica ratiofalls below 3 : I, and in which aluminium hydroxide is present.Pneumatolytic weathering gives rise to kaolinite, A120,,2Si0,,2H,0.Since apatite and muscovite are readily decomposed by pneumato-lytic agencies, but are very resistant to ordinary weathering, theirpresence or absence enables us to distinguish between kaolinite andthe products of ordinary weathering.In this connexion, we maynote that a method of distinguishing between kaolin and allophanehas been based on the behaviour of these substances towards diluteacetic acid.98 A kaolin, in which the ratio A120s: SiO, was 1 : 2,was shaken for eight days with 6 or 12 per cent. acetic acid. Onlyfrom 1 to l b per cent. dissolved, and in the solution equal molecularproportions of alumina and silica were found. Allophane treatedsimilarly was much more freely attacked, some 11 per cent.beingdissolved. The ratio of alumina to silica in the dissolved part wasthe same as in the mineral itself. Laterites have been the subjectof investigation by H. Arsandaux,QQ who, from analysis of a numberof samples, has arrived at the conclusion that laterites are normalmuscovites in which water of constitution has progressively replacedthe alkalis. The silicates are gradually replaced by hydrated oxidesof iron and aluminium, as the result of secondary change.Eryptotile is an alteration product of prismatine, with which itoccurs at Waldheim in Saxony.1 Its composition agrees with thesimple formula RAlSiO,, but its mode of occurrence m d propertiessuggest that it is to be regarded as a member of the mica family inZeitsch. anorg. Chem., 1910, 66, 322 ; A,, ii, 419.98 R.van der Leeden, Ccntr. Min., 1910, 289 ; A . , ii, 621.99 Compt. rend., 1910, 150, 1698 ; A . , ii, 723.J. Uhlig, Zeitsch. Kryst. Min., 1910, 47, 215 ; A . , ii, 311248 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.which alkalis are absent, and the formula, is therefore to be writtenH,Al,Si,O,,.Langbeinite occurs embedded in rock-salt a t Hall, Tyrol.2 It formsnodules, which, if exposed to the atmosphere, soon become coatedwith picromerite, K2S04,MgS04,6H20, and epsomite. The com-position of the material is K,S0,,2MgS04. Refractive index, 1-5347(sodium light). Sp. gr. 2.825.Lansfordite.-The water from the mineral springs at Rohitsch,Styria, when evaporated a t 2O, deposits large monoclinic crystals ofMgC03,5H,0.3 This substance is not formed above 6O, and beginsto lose water at 20°.A comparison of these crystals with those oflansfordite, hitherto believed to be an anorthic mineral of theformula 3MgC03,Mg(OR)2,21H,0, leads t o the conclusion that theyare identical. Ths crystallographic constants are as follows :a : b : c=1*6079: 1 : 0.9524, P=78O36’. These conclusions havereceived confirmation from another quarter,4 for it has been foundthat when the mixture of calcium and magnesium oxides obtainedby calcining dolomite is suspended in water and treated a t loo withcarbon dioxide under a pressure of from 5 to 6 atmospheres, onlyMgO is dissolved, and the filtrate deposits monoclinic crystals,a : b : c = 1.6323 : 1 : 0.96676, P = 77O51’, which have the compositionMgC?0,,5H2O, and appear to be identical in form with lansfordite.Lanthanite.-Material from Bastnas, Sweden, has been found tocontain 28.34 per cent.(La,Di),03, and 25.52 per cent. of ceriumoxide.5 Like the American lanthanite, its composition may beexpressed by the general formula R,03,3C0,,8H,0.Ludgwigite has recently been observed in Montana: havingonly been known previously from Hungary. The formula3MgO,FeO,Fe2O,,B,O3~ assigned to the Hungarian minera.1, has beenconfirmed by a new analysis, and the American specimen shownto conform to the same type, part of the magnesia being, however,isomorphously replaced by ferrous oxide. The mineral occurs insmall, dark green or nearly black spherulites in a metamorphiclimestone containing large bodies of magnetite.Manganosite.-This rare species has hitherto only been foundin Sweden, but recently it has been observed as irregular, darkgreen grains, exhibiting cubic cleavage, associated with frankliniteand zincite at Franklin Furnace.7 Its formula is MnO, smallquantities of zinc being also present.2 R.Gorgey, Tsch. Min. Mitt., 1909, 28, 334 ; A., ii, 309.3 H. Leitmeier, Zeilsch. Kryst. Mzn., 1909, 47, 104 ; A., ii, 49.4 G. Ceshro, BUZZ. Acad. roy. Belg., 1910, 234 ; A., ii, 613.6 W. T. Schaller, Anaer. J. Sci,, 1910, [iv], 30, 146 ; A., ii, 873.7 C. Pelache, ibid., 29, 178 j A . , ii, 219.G. Lindstrom, Geol. F6r. Fiirh. Stockholm, 1910, 32, 206 ; A., ii, 965MINERALOGICAL CHEMISTRY. 249Mica Group.-The analyses which have been published ofmembers of this group call for no special remark, but we may notethat the green mica crystals which occur in the dolomite of theBinnenthal have been shown by Prior8 to belong to the varietytermed fuchsite.MicroZite.-This mineral is essentially a calcium pyrotantalate.A specimen from Wodgina, Western Australia, has been analysedby E.S. Simp~on.~Mineruite.-A soft, white, powdery substance, apparently homo-geneous, from the Island of RQunion, has been found to have thecomposition 2A1P0,,(K,NH,,H)3P0,,7~H20. It appears t o besimilar t o minervite and palmerite.1°NepheZine.-The so-called pseudonepheline or pseudosommite,from Capo di Bove, resembles nepheline in its crystallographiccharacters, but has somewhat different optical properties.Theformula is (Na,X)AISiO,, corresponding with a lower percentage ofsilica than is found in nepheline.11Nespuehonite.-The waters of the mineral springs at Rohitsch,Styria, contain carbon dioxide, with considerable quantities ofmagnesium carbonate, sodium carbonate, and sodium sulphate.12On evaporation a t temperatures of 1 3 O or 20°, these waters depositorthorhombic needles of nesquehonite, MgC03,3H,0, followed aftersome days by indistinct crystals of aragonite, a mineral found infine groups at the spring (see also lansfordite).Paigeite.-This mineral occurs associated with hulsite and mag-netite in the neighbourhood of Brooks Mountain, Seward Penin-sula.l3 As is also true of hulsite, it has been found that theformula first assigned to the mineral needs revision, the amountof boron having been at first considerably over-estimated, and thetin altogether overlooked.Ths formula now suggested for paigeiteis 30Fe0,5Fe203,Sn0,,6B203,5H,0, although the possibility that thesubstance may be a borate of iron mixed with hulsite has to beborne in mind.Pat?*onite.-In the course of a description of the vanadiumdeposits in Peru, D. F. Hewett14 gives analyses of specimens ofpatronite purer than that examined by Hillebrand, and suggeststhe formula V2S5 + nS. Secondary vanadium compounds are formedMin Mag., 1910, 15, 385 ; A., ii, 781.Austral. Assoc. Report, 1909, 310 ; A., ii, 1077.F. Zambonini, Rend. Aceacl. Sei. Fis. Mat. Napoli, 1910, [iiia], 16, 83 ; A,,H.Leitmeier, Zeitsch. Kryst. Jfin., 1909, 47, 104 ; A., ii, 49.l3 W. T. SchalIer, Amer. J. Sci., 1910, [iv], 29, 543 ; A., ii, 621.I4 Trans. Amer. Inst. Mining Engineers, 1910,lo A. Lacroix, Bull. Soc. frang. Min., 1910, 33, 34 ; A., ii, 308.ii, 107s.(1909), 274 ; A., ii, 719250 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTHY.by the oxidation of these ores, and preliminary descriptions aregiven of these, some of which may prove to be new species.PiZoZiite.-Thin, flexible sheets of ‘‘ mountain leather,” fromvarious localities in the west of the Province of Siichwan, China,consists of interlaced fibres, showing straight ext(inction.15 The com-position corresponds with the formula A1,Si,O7,2MgSi,0,,7H20, andthe mineral is therefore not a variety of asbestiform serpentine oramp hibole.Plwnboniobite was mentioned among t,he new minerals last year.The following formula is now proposed for it 16:R”,Cb207,R”’4(Cb,07)3,where R” represents Pb, Fe, UO, and Ca, and R”’ represents Y,Gd, Sm, and Al.PI-ismatilne.-This mineral occurs in granulite at Waldheim, inSaxony, and was described by A, Sauer in 1886.Its identity withkornerupine was suggested by Ussing in 1889. It has lately beenthe subject of a careful reinvestigation,l7 which, whilst confirmingin the main the work of previous observers, has resulted in thedetermination of the axial ratios of the orthorhombic crystals, andin a more accurate knowledge of the chemical composition. Thisappears to be best expressed as NaH3MgGAl,,Si7O4,, some of themagnesia being replaced by ferrous oxide, and some of the aluminaby ferric iron.The composition of kornerupine may be representedby the analogous formula H2Mg7A1,2Si70,, ; the two minerals maytheref ore be regarded as distinct but isomorphous species.Pucherite.-A specimen of this rare vanadate of bismuth hasbeen found in chrome-yellow, crystalline grains in the concentratesfrom an oxidised quartz reef at Niagara, Western Australia.18 Thecomposition is represented by the formula BiVO,.Pyroxene Group-Analyses of the varieties termed jeffersoniteand schefferite have been published by C . Pa1a~he.l~ The com-position of a green chrome-diopside from a diamond pipe inRhodesia has been recorded by F. P. MennellFO and a number ofanalyses of augite from the basalt of the Rho, Mountains havebeen made by X.Galkin.21 The last are all very similar in com-position, and the results obtained have been fully discussed in thelight of the work of Penfield and Tschermak, although no verydefinite conclusions have been drawn.15 G. S. Whitby, Min. Mag., 1910, 15, 294; A., ii, 313.16 0. Hauser, Ber., 1910, 43, 417 ; A., ii, 221.l7 J. Uhlig, Zeitsch. Rryst. blin., 1910, 47, 215 ; A., ii, 311.I* E. Griffiths, J. Roy. SOC. Ne,iu South Wales, 1908, 42, 251 ; A., ii, 47.19 Amer. J. S’ci, 1910, [iv], 29, 180 ; A , , ii, 219.20 Quart. J. Ceol. SOC., 1910, 66, 353 ; A . , ii, 1078.21 Jahrb. Mi%. BeiL-Bd., 1910, 29, 681 ; A., ii, 721MINERALOGICAL CHEMISTRY. 251Rhubdite is a phosphide of iron and nickel found in minute,tetragonal prisms in certain meteoric irons, and a phosphide of ironformed by combustion in the coal mines of Commentry, France,has been referred to the same species.The latter substance haslately been subjected to metallographic examination and chemicalanalysis,22 with the result that it has been shown to be a mixtureof iron and a phosphide, Fe3P, together with small quantities of FeS.Rhodomite.-Well-crystallised material from the Radauthal, Harz,has a composition agreeing with the general formula R”Si03,23where R” is Mn and Ca, (CaO=14*18 per cent.).Riuotite.-At Trazein, near Sentein, France, an ore containingcopper, silver, and antimony is being worked in dolomites ofDevonian age.24 On microscopical examination, it was seen toconsist of grains of tetrahedrite surrounded by concentric layers of agolden-yellow, isotropic material, which proved to be stibiconite,Sb,O,,H,O, tpgether with layers of a, greenish-yellow, birefringentsubstance.The latter was soluble in ammonia and in acetic acid,and is malachite. A mineral termed rivotite, originally describedfrom Spain, has similar characters, and is therefore to be regardedas a mixture of malachite and stibiconite resulting from thealteration of tetrahedrite.Sapphire.-A. Verneuil25 has found that this gem can be madeartificially by fusing in the oxyhydrogen flame alumina, containing1.5 per cent. of magnetite and 0.5 per cent. of titanic acid. Thephysical properties of these stones agree closely with those of thenatural mineral, and on analysis traces of Fe,O, and from 0-11 to0.13 per cent. of TiO, were found.26Scapotit e Grozcp.-A specimen of mizzonite from Cape d’Arco,Elba, has been found to consist of three molecules ofmarialite, Na,[A1C1]Al,[Si308]3, and two molecules of meionite,Ca,[A10]A12[ Si,AlO&, and to possess the corresponding physicalproperties.27The views as to the constitution of the scapolite group, originallypropounded by Tschermak, have, moreover, been abundantly con-firmed by Himmelbauer,28 who, in a valuable and elaborate memoir,has tabulated the results of previous observers, and has recordedthe observations he himself has made on a number of members OFthis family.H e has measured with great care the densities andOswald, Bztll.Soc. franq. &Fin., 1910, 33, 88.a3 J. Fromme, Tsch. Min. Mitt., 1909, 28, 308; A., ii, 314.24 A, Lacroix, Bull. S‘oc. frffinq. Min., 1910, 33, 190; A . , ii, 782..Lj Contpt. rend., 1910, 150, 185 ; A . , ii, 212.26 A. J. Moses, Amer. J. Sci., 1910, [iv], 30, 271 ; A., ii, 965.27 E. Manasse, Atti R. Accnd. Lineei, 1910, [v], 19, ii, 211 ; A., ii, 967.28 Sitmngsber. K. Akffid. Wiss. Wieie., 1910, I19 i, 115252 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,the crystallographic and optical constants of specimens from variouslocalities, and has determined their melting points by the methodselaborated by Doelter. Further, he has examined, by Tschermak’smethod, the nature of the silicic acids, from which these substancesare derived, and has by analysis estimated the proportions in whichthe two constituents, meionite and marialite, enter into their com-position.He concludes that from the crystallographic, physical,and chemical aspect, the scapolites exhibit the criteria, of an iso-morphous series. Within the limits of experimental error, theirproperties are continuous functions of their composition. The factthat these limits axe tolerably wide is due to the impurity of thematerial investigated .SeZigmannite.-From a, consideration of its crystalline form, itwas considered probable that this rare mineral from the Binnenthalwould prove t o be a sulpharsenite of copper and lead, CuPbAsS,,isomorphous with bournonite, CuPbSbS,. This prediction has nowbeen fully confirmed by an analysis made by G.T. Prior.29UZZmannite.-An interesting occurrence of this mineral has beenreported from the New Brancepeth Colliery, near Durham.30. Thecrystals are of cubic or octahedral habit, and often form parallelgrowths with the galena with which they are associated. Thecomposition is NiSbS.Vanthofite.-This mineral occurs as nodules embedded in blodite,(Na2S0,,MgS04,4H20), and associated with loweite,at Hall, Tyrol. The composition agrees very closely with theformula 3N+S04,MgS0,.31 The crystal system is doubtful, but themineral is birefringent, and the following values were obtained forthe refractive indices by the immersion method in sodium light:a = 1.4855, fi = 1.4876, y = 1.4893.Va&cite.-The formula, Al2O,,P20,,5H2O has been assigned to apale applegreen substance incrusting black shale in an iron mineat Vashegy, Hungary.32 The mineral contains one molecule morewater than is usually present in variscite.Vesuviunit e .-Bluish-gr een, fibrous material from Franklin Fur -nace agrees closely in composition with cyprine from Tellemarken,Norway, although the latter contains less water and more fluorine.%The formula is H,(Al,Fe),Ca,,Si,,O,,.WiZZemite.-The axial ratio and refractive indices of colourlessor pale green crystals from Franklin Furnace have been found to(2N+S04,2MgS04,5H20),Sp. gr.= 2.694.2* Min. iMag., 1918, 15, 385 ; A . , ii, 781.so L. J. Spencer, ibid., 302; A., ii, 307.31 R. Gorgey, Tsch. Him. Mitt., 1909, 28, 334 ; A., ii, 309.32 K.Zimhyi, Ber. aus Ungarn, 1909, 25, 241 ; A., ii, 307.33 C. Palache, Amer. J. Sci., 1910, [iv], 29, 184 ; A, ii, 219MINERALOGICAL CHEMISTRY. 253be as follows 34: a : c = l : 0.6612, o =1*6939, ~=1*7230 (sodiumlight).WoZframite.-The mixture of rare earths obtained from theZinnwald wolframite contains about 56 per cent. of scandium oxide,which appears to be present to the extent of about 0.1 per cent. inthe original mineral. A similar proportion has been detected inwolframite from Sadisdorf, near Schmiedeberg.35 The presence ofscandium in wolframite from Sadisdorf has been confirmed byEberhard,36 who has also detected it spectroscopically in a numberof minerals and rocks, more particularly in zeschynite and cassiteritefrom Swaziland, in monazite and wiikite from Finland, and incassiterite from Japan.It appears to be almost constantly presentin the minerals and rocks associated with tin-ores.Zeolite Group.-Among the recent investigations of members ofthis group we may notice, in the first place, the careful study ofthe acicular crystals of mesoZit,e from the Faroe Islands, for whichwe are indebted to R. Gorgey.37 The crystals are apparently maneclinic, but optical examination shows that they are really triclinicand twinned. In composition they correspond with a mixture ofone molecule of natrolite, NazA1,Si,0,,,2H,0, with two molecules ofscolecite, CaAl,Si~0,,,3Hz0. As both these minerals are, however,monoclinic, the conclusion is arrived at that mesolite is to beregarded as a double salt, rather than as an isomurphous mixture,The optical properties of mesolite and allied substances have alsobeen examined in detail by G.Cesbr0.~8 The large twinned crystalsof phillipsite, which occur in basalt at Sirgwitz in Silesia, contain anunusually high percentage of magnesium oxide (4.53 per cent.).39Their composition may be represented as15 SiO2,4AlZO3,5 (Ca,Mg,K,) 0 , 2 OH,O.Magnesium oxide has also been reported by J. Fromme40 in amesolite from the Radauthal, Harz, and in an apophyllite from thesame locality. The latter is also remarkable as containing alumina(1-78 per cent.), apparently as an essential constituent.Here may be recorded some interesting experiments which havebeen made on the absorption of vapours by zeolites.It has longbeen known that certain zeolites, when dehydrated, will absorb notonly water, but air and ammonia, and it has now been shown thatvapours of iodine, bromine, mercury, calomel, cinnabar, and sulphur34 C. Palache, Amer.'J. Sci., 1910, [iv], 29, 184 ; A , ii, 219.35 R. J. Meyer and H. Winter, Zeitsch. anorg. Chem., 1910, 67, 498 ; A., ii, 853.38 Sitz~~gsber. K. Akad. Wiss.Berlin, 1910, 404 ; A . , ii, 509.37 Tsch. Niit. Mitt., 1909, 28, 77 ; A., ii, 312.38 Bull. Acad. roy. Belg., 1909, 435. '' P. Barbier and F. Gonnard, Bull. Sue. franc. Xh., 1910, 33, 79 ; A., ii, 418.Tsch. Hin. Mitt., 1909, 28, 305; d., ii, 314254 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.may be taken up.41 Chabazite, for example, may absorb as muchas 27 per cent.of mercury. Marked changes in the optical pro-perties accompany these phenomena. We may also draw attentionto an investigation into the rate at which an artificial sodium zeoliteis attacked by certain chloride solutions.42 It is found that thevelocity of the reaction is at first very great, but graduallydiminishes. Rise of temperature increases the rate of change, andwhen solutions of the chlorides of magnesium, calcium, strontium,and barium are employed, increased velocity of attack accompaniesincrease in the atomic weight of the metallic iron.Meteorites.Laboratory work on the properties of nickel-iron alloys mightfairly be expected to throw light on the nature of the meteoricirons, but although attempts in this direction have not been wanting,the conclusions so far arrived at appear to be somewhat contra-dictory. Last year reference was made to a paper by Fraenkel andTammann, in which evidence was brought forward to prove thatmeteoric nickel-iron is unstable a t low temperatures.That this isnot the case. is now maintained by Guertler,43 who has attemptedt o show that the formation of the characteristic meteoric structurecan only occur at low temperatures and with extreme slowness. I nthis connexion, we may note that, according to Ruer and Schiiz,44the system iron-nickel gives a continuous freezing-point curve with ashallow minimum. From these experiments and from a series ofdeterminations of the temperatures of magnetic transiormation,they find indications of the existence of a compound FeNi,.Among recent investigations of individual meteorites, the follow-ing may be recorded.Angra dos Reis.-This stone is remarkable as consisting mainly(92.89 per cent.) of an augite resembling in its optical characters thetitaniferous augite of certain basaltic rocks.The other con-stituents are olivine, pyrrhotite, apatite in small grains, and glassparticles. On looking for titanium, 2-39 per cent. of TiO, wasfound in the stone.45 The analysis published in 1887: in which thepresence of titanium was overlooked, therefore requires correction.Chandakapur.-A thorough examination has been made of aportion of the specimen preserved in the Oxford UniversityMuseum.46 The meteorite consists mainly of olivine (53'47 percent.) and pyroxenes and felspars (33.89 per cent.), and bears a41 F. Grandjean, BdZ. SOC. fmnp Min., 1910, 33, 5 ; A . , ii, 311.42 A. G. ljoroschewsky and A. Bardt, J. Rzus. Phys. Chein. Sbc., 1910, 42, 435 ;44 MetaElurgie, 1910, 7, 415 ; A . , ii, 959.45 E. Ludwig and G . Tschermiik, Tsch. illin. Mitt., 1909, 28, 110; A., ii, 315.H. L. Bowman and H. E. Clarke, Bin. Mag., 1910,15, 350 ; A , , ii, t83.A., ii, 615. 43 Zeitseh. physikal. Chem., 1910, 74, 428 ; A., ii, 833MIXERALOGICAL CHEMISTltY. 255noticeable resemblance to the chondrites of Makariwa, Krahen-berg, Waconda, and Nerft. The silicates are very rich inaluminium. The metallic alloy (5.8 per cent.) is rather poor innickel. The other constituents are troilite, schreibersite, chromite,magnetite, and rust.Coon B.utte.-The origin of the great crater-like depression knownas Coon Butte, in Arizona, has been the subject of much speculation.The presence in and around it of numerous masses of meteoric ironhas suggested that it was produced by the impact of an immensemeteorite or swarm of meteorites. This view was discussed byMerrill in 1908, and has met with considerable acceptance, althoughtho alternative explanation of formation by volcanic action is stillpreferred by some. D. M. Barringer47 finds support for themeteoric hypothesis in the results of a careful exploration of thecrater, and has recorded his observations and conclusions in abeautifully illustrated memoir (privately printed), entitled “ TheMeteor Crater in Northern Central Arizona.”Goamus.-This meteorite takes its name from the farm calledGoamus, near Gibeon, in German South-West Africa.48 It is aniron, and remarkable for its octahedral structure, lamellae parallelto cube faces being of subordinate importance.Mummpeowie.-The discovery of an iron meteorite exceeding a tonin weight has been reported from Murnpeowie, South Australia.49Its fall was not observed, but there seems reason to believe that ittook place in recent times.Shrewbury. - A much-weathered mass was found in 1907about seven miles north of Shrewsbury, York County, Penn-~ y l v a n i a . ~ ~ On examination, it proved to be an octahedrite ofmedium coarseness, with broad bands of kamacite bordered byt aenite.S,irnondium.-Two much-rusted masses, found about a foot belowthe surface in gravel at Simondium, Cape Colony, have beendescribed by G. T. Prior.51 They may be placed in the howarditegroup of Brezina’s classification, and consist mainly of enstatite,olivine, and plagioclase f elspar, together with magnetite, nodulesof troilite, and particles of nickel-iron.Thornson.-A small mass was found a t Thomson, McDuffie County,Georgia, in 1888, but its existence has only recently been madeIt is a t present under investigation.Troilite nodules and schreibersite are also present.It appears to resemble the MOcs meteorite.A. HUTCHINSON.47 Smithsonian Misc. Contributions, 1908, 461.49 L. Laybourne Smith, Amer. J. Xci., 1910, [iv], 30, 264.6o 0. C. Farrington, ibid., 29, 350 ; A . , ii, 420.51 Min. Mag., 1910, 15, 312; A., ii, 315.62 G. P. Merrill, Anzw. J. Sci., 1910, [iv], 29, 368.F. Rinne, Jahrb. Min., 1910, 1, 115

ISSN:0365-6217    

DOI:10.1039/AR9100700225

出版商:RSC    

年代:1910

数据来源: RSC

摘要:

RADIOACTIVITY.Standards and Units of Measurement.AT the International Congress of Radiology at Brussels held duringthe year, after a general review of the question by Rutherford, anInternational Standards Committee was appointed and issued aRep0rt.l As a member of this committee, Mme. Curie has con-sented to prepare a standard tube containing a known weight,approximately 20 milligrams, of radium (element) as chloride, whichis bo be kept in Paris, and is to serve as the primary internationalstandard of radium. By suitable y-ray methods of measurement,any required number of standards, having a known ratio to theprimary, can then be prepared without elaborate chemical processes.The relatively somewhat large quantity chosen is necessary to securea high degree of accuracy, the standard being primarily a standardmass of radium which, once prepared, will serve subsequently as SLstandard of y-radiation, but for many purposes smaller sub-standardsof about 1 milligram will be more generally useful.For measure-ment of smaller quantities of radium, such as are found in naturallyoccurring materials, the emanation generated by the radium isalmost invariably employed. A new unit for the quantity of radiumemanation- was adopted, to be called the " curie," with the sub-divisions millicurie, microcurie, etc., the curie being the mass ofemanation in equilibrium with one gram of radium. Its mass istherefore A,/A, gram, where A, and A~ are the radioactive constantsof radium and its emanation respectively.The unit frequentlyused, the amount of emanation generated per second by a gramof radium, is A, curie, A, being expressed in seconds. Recentdeterminations agree in making the value of A,(sec.)-l, 2-08 x(p. 279).2The absolute value of the ionisation current, in vessels ofcylindrical form, given by known quantities of emanation has alsobeen the subject of recent investigation.3Le Radium, 1910, 7, September Sqqdement, p. 65.Mrne. Curie, Le M i u r n , 1910, 7, 32 ; A., ii, 374.W. Duane and A. Laborde, Comnpt. rend., 1910, 150, 1421 ; A . , ii, 676RA DlOACTIVlTY. 257The preparation of the primary standard will therefore bringabout a great advance in reducing all radioactive measurements toa common standard, and in simplifying the expression of theresults. Each laboratory now possesses its own provisional radiumstandard, as was the case in electrical laboratories with standardsof resistance a few decades a.go.The adoption of a commonstandard is of importance, not only for scientific, but also intechnical, work where considerable uncertainty prevails.a-Rays.Countin9 Experiments.-Several important investigations havebeen published depending on the counting of a-particles by thescintillation method. I n the first place, fresh information has inthis way been obtained of the number of a-particles emitted in thesuccessive changes of the thorium and actinium series.4 Twoparallel zinc sulphide screens, placed near together, formed two sidesof a box into which emanation was allowed to diffuse from pre-parations of thorium or actinium.The number of scintillationsfrom the active deposit and emanation together in equilibriumwas in each case three times greater than that found for the activedeposit alone, after the supply of emanation had been cut off andthat initially present allowed to decay. Since in each case twosets of a-particles are furnished by the active deposit, four mustbe furnished by the emanation. By means of two similar micro-scopes, focussed on exactly opposite portions of the two screens,two observers counted the number of simultaneous scintillations.For the radium emanation and active deposit only a few per cent.of the scintillations occurred in pairs, but for the actiniumemanation twethirds of the total number of scintillations occurredas pairs simultaneously.For the thorium emanation a large numberof rapidly succeeding scintillations were recorded, the intervalvarying from 0.5 second downward. Even with very few scin-tillations per minute, the appearance of a scintillation was usuallythe signal f o r that of another, which followed the first closely, aftera distinct but very short interval. It appears therefore that thechange of the thorium emanation is double, the product of theemanation having a period of average life of the order of one-fifthof it second. Interesting and suggestive as the experiments are,they are still far from complete, and many points remainunanswered, the method of investigation being extremely difficultand trying to the observer.The detection of the single scintillation,although possible, is very near the limit of visibility, especially inAnn. Report, 1909, 236 ; H. Geiger and E. Marsdcn, Physika?. Zeitsch., 1910,11, 7 ; A., ii, 92.REP.-YOL, VII. 258 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the case of the low-range a-particles of uranium. The obviousextension of the method just described to the problem whether thetwo a-particles from uranium are simultaneous or successive has notyet been accomplished. On the other hand, determinations havebeen made of the relative numbers of a-particles given by pureuranium and thorium compounds and by uranium and thoriumminerals respectively, in which the complete disintegration seriesexist in equilibrium.These experiments have completely sub-stantiated the view that uranium, alone in the uranium series, emitstwo a-particles per atom disintegrating, and, on this basis, bearout remarkably closely the number calculated from the fundamentalconstant 5 representing the number emitted per second (3.4 x 1010)per gram of radium (free from products). Thus the calculatednumber, per second, per gram of uranium in equilibrium, is 96,700.The number found in one investigation6 was 73,600, and in theother,' which was more complete, 96,000. I n the latter research,the number found per gram of uranium in pure uranium oxide was23,700, as compared with 11,600, the calculated number, if onlyone a-particle was expelled from each atom of uranium.The distribution of the a-particles among the members of thethorium series, and the total number emitted per atom of thorium,are, as already pointed out, still incompletely known, but the totalnumber given per second by one gram of thorium in equilibriumwith its products was found to be 27,000.The period of uraniumis known from the ratio of uranium and radium in minerals andthe period of radium, but no such method for determining theperiod of thorium is possible. The datum just referred to will,however, enable the period of thorium to be calculated as soon asthe total number of a-particles emitted per atom of thorium dis-integrating is known. It has always been clear tha,t the period ofthorium must be many times greater than that of uranium.An interesting result of the foregoing investigation was that, thescintillations produced by the a-rays of ionium (range 2.8 cm.) wereas bright or brighter than those from the a-rays of uranium, therange of which has previously been assumed, from indirectcalculations, to be 3.5 cm.A preliminary direct estimate of therange of these particles by a scintillation method gave 2.7 cm., thelowest yet recorded. The low range of both a-particles fromuranium is, on Rutherford's rule? very strong, although not entirelyconclusive, evidence that they cannot, be derived from two successivechanges, unless the second change is a t least as slow as that ofCalled Q previously, Aim. Beport, 1909: 234.H. Geiger and E. Rutherford, Phil. Mag., 1910, [vi], 20, 691 ) A., ii, 917,-4m.Keport, 1907, 311.6 J. N. Brown, PYOC. Aoy. SOC., 1910, A, 84, 151 ; A., ii, 917RADIOACTIVITY. 259ioniurn. But in this case uranium must be a chemically non-separable mixture of two elements differing in atomic weight by4 units, in the constant proportion due t o their genetic relation-ships (compare p. 285). The distribution of the a-particles from apolonium source with regard to time was found to be such as isto be expected from the theory of probability for a purely randomdistribution.YThe Sadden Disappearance of the a-Particle at the End of itsRange.-Experiments10 have shown that as the velocity of thea-particle diminishes in its passage through matter, there is a rapidincrease in its liability to be scattered or turned from its initialdirection by collision with an atom.The power of different atomsto scatter a-rays was found to be directly proportional to the atomicweight, and for gold to be inversely proportional to the cube of thevelocity of the a-particle. A redetermination l1 of the diminutionof velocity during passage through matter showed that the velocityof the a-particle a t any point in its path is proportional t o thecube root of the range it has still to run. A t a point about 5 mm.from the end of the range, the number of a-particles in a stream,which previously has remained constant during the passage throughmatter, begins to diminish rapidly. This is not due t o initialdifferences in the velocity of expulsion, for the most careful testsfailed to show any such differences, but is brought about bydifferences in the individual chances of collision with the moleculesof matter during the passage and by scattering.The ranges ofBragg are in reality the extreme ranges, the average ranges beingaome millimetres less. It is probable that the very rapid increasein the liability of the a-particle to be deflected and scattered oncollision with an atom as its velocity diminishes accounts for theapparent suddenness with which the particle passes out of the rangeof detection. For the individual a-particle, the diminbtion ofionising power is not quite so sudden as is indicated by the Braggcurve, which is an average curve for a pencil of a-particlestravelling, towards the end of the path, at slightly different speeds.FZuorescemce.-A quantitative examination of the fluorescence ofzinc sulphide, willemite, and barium platinocyanide, exposed toa-rays, has shown that the reduction of luminosity with continuedexposure, which is least rapid for willemite, and most rapid forbarium platinocyanide, is accompanied by only a small reductionm the number of scintillations observed.12 The theory is suggestedthat " active centres " exist in the fluorescent substance, whichE.Rutherforcl and H. Geiger, Phil. Maq., 1910, [vi], 20, 698; A., ii, 917.H. Geiger, Proc. Roy. Soa, 1910, A, 83, 492 ; A., ii, 472.l1 H. Geiger, ibid., 505 ; A., ii, 473 ; compare Am. Beport, 1906, 335.J2 E. Mareden, z3id., 548 ; A., ii, 565 ; E. Rutheiford, ibid., 561 ; A ., ii, 665,8 260 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRYdissociate and give out light when struck by an a-particle, but,after having been once struck, become ineffective. At first eacha-particle causes the dissociation of a number of these centres, but,as they become used up, fewer are available, causing the brightness,but not the number, of the individual scintillations to diminish.On this view it is cadculated that the mean diameter of the activecentres in zinc sulphide and willemite is not very much larger thanthe molecular diameter, which precludes the possibility that thescintillations are produced by the mechanical cleavage of smallcrystals. I n barium platinocyanide the diameter of the activecentres appears to be about a hundred times greater than in zincsulphide.It has. long been known that similar changes are producedin barium platinocyanide by grinding, and that simple re-crystallisation restores the salt t o its initial condition.13Pleochmic HuZos.14-Just as the photographic plate reveals starstoo faint to be visually detected, the pleochroic halo found in certainmicaceous minerals, particularly biotite, zinnwaldite, and horn-blende, integrates the a-ray effect of ages from tiny inclusions ofradioactive material, themselves often barely visible in the centreof the halo. The diameter of a nucleus capable of evolving a fullydeveloped halo is often less than 5 x cm., and even if this wereuraninite, the quantity of radium it contains is only 10-16 gram,and the number of a-particles given off is only about two per day.I n certain embryonic halos, still quite unmistakable, the mass ofmatter in the nucleus is often sixteen times less, and as the materialcausing the halo is often zircon, not a very radioactive mineral, itfollows that by this means quantities of radioactive matter can berecognised by mere inspection, which are many thousands of timesless than can be detected in any other way.The production of thehalo depends on the character of the surrounding matrix, and inone specimen of Leinster biotite, the halo was often found to beabruptly bisected where the darkened biotite abutted against com-pletely limpid muscovite. I n granites and syenites the halo is notcontinued into the quartz or felspar adjacent to the biotite orhornblende in which it develops.As the a-ray-sensitive mica isoften associated in rocks with many common elements, without theOccurrence of pleochroic halos, it may be concluded that a-radio-activity, at least, is certainly not a common property of matter toofeeble to be directly detected.A careful microscopic examination of these halos has revealeddetails of extraordinary interest. Owing to the ionisation of thea-ray increasing rapidly towards the end of it's range to a maximumjust before it ceases to ionise, the darkening in the halo is notl3 Ann. &port, 1905, 301.l4 J. Joly and A. L. Fletcher, Phil. Hag., 1910, [si], 19, 630RADJOACTIVITY. 261uniform, or uniformly varying from the centre to the edge, butthere exist well-defined rings of greater intensity correspondingwith the separate a-rays of different ranges. Taking into accountthe chemical composition and the density of the material and theknown law of absorption of the a-rays, the various features of thehalos correspond exactly with the known a-rays.No central(‘ pupil ” is ever found less in diameter than the range of the ioniuma-ray, nor any (‘ corona ” greater than corresponds with ths rangeof the a-ray from thorium-C. The uranium halos can be dis-tinguished easily from the thorium halos, which are less frequentlyencountered, but both have been found side by side in the samespecimen. I n biotite, with nuclei of negligible size, the overalldiameter of a good completely developed uranium halo is 0.033 mm.,and of a thorium halo 0.040 mm.All stages of development havebeen observed in a single large crystal of biotite (variety, haughton-ite) from Leinster granite. The phenomenon commences with theappearance of the embryonic halo, perfectly circular and usuallystructureless o r with only a slightly darkened peripheral border,due to the slowest a-rays (ionium, radium, uranium). This doesnot start from the centre outward, but the earliest appearance isa very faint, spherical darkening of the full diameter. These simplehalos may be quite blackened up before the next stage, due to thea-rays of radium-A and -C, appears. The a-rays of radium-P andthe emanakion enlarge the diameter of this central “ pupil ” some-what, a t a later stage of development, without any clear annulus.The next stage seems to be the development of the ‘(corona” dueto radium-C, and it is only after this has commenced that theinner corona due to radium-A appears, which, quite inexplicably,seems always somewhat backward in its development.A beautifulseries of microphotographs accompanies the paper, and in one, ofa halo in biotite ( x 450 diameters), the central pupil, the outercorona due t o radium-C, and the inner due to radium-A are shownwith exquisite detail. I n the last stage of the development, onlythe outer corona and central pupil, enlarged to somewhat morethan the radius due to radium-A, can be separately distinguished,which enlargement may be due to actinium a-rays, but has not yetbeen fully explained.Fine capillary tubes of soda-glass, which havecontained radium emanation, show in transverse section a colouredregion extending about 0.04 mm., corresponding with the naturalpleochroic halo.15Helium.Production of Helium h y Radioactive Substances.-The identityof the a-particles expelled in the radium series with atoms of heliuml5 E. Rutherford, M e r n . Manchester Phil. b’oc., 1909, 54, [v], 1 ; A., ii, 175262 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.has been completely established,le and it is therefore advisable toconsider the researches on the connexion of helium with radio-activity immediately after those dealing with the a-rays. Two newdeterminations of the rate of production of helium from radium havebeen made.The first l7 refers to the experiment already described,l8in which the rate of production previously given, 0.37 cu.mm. (pergram of radium per day), was erroneous, and should have been0.499 cu.mm. Over a further period of nine months the rate ofproduction was 0.463, and it is considered that the true valueprobably lies between these two limits. The theoretical value is0.433 cu.mm. I n the second determination,19 0-2 gram of radiumchloride, freed by chemical treatment from polonium and radium-D,was allowed to accumulate helium for eighty-three days. The rateof production found corresponded with 0.447 cu.mm. (per gramper day). The production of helium from polonium, which isreferred t o incidentally in the work just described, has beenestablished in the investigation on this substance,eo described morefully later (p.281). Part of a very active polonium preparation,derived from several tons of pitchblende, generated 1.3 cu.mm. ofhelium in one hundred days, as compared with the value 1.6 cu.mm.,calculated from the number of a-particles expelled. An importantdetermination of the rate of production of helium in the mineralsthorianite and Joachimsthal pitchblende 21 has given the followingresults :72.65 2'79 x 2'67 x Thorianite { 13.1Pitchblende ............... 37 *6 - 3.16 x 2-95 xThe table shows the percentage of uranium oxide and thoria inthe minerals, and the rate of production of helium found in C.C. pergram of mineral per annum. The work was published prior tothat already considered (p.258) on the number of a-particlesexpelled per second per gram of uranium and thorium in minerals,but I have, from these numbers, calculated the theoretical rates ofproduction of helium for the three minerals, and shown the resultin the last column of the table. Considering the great difficultiesof the experiments, there is a wonderful agreement between thevalues found and calculated.Helium in Mi.neraZs.-The minimum ages of the two thorianitesU,OV Tho,. Rate found. Rate calculated.24 5 65'44 3.7 X ~ O - ~ 3 ' 4 2 ~ 1 0 - ~ .................A m . Report, 1909, 233.Sir J. Dewar, Proc. Roy. Xoc., 1910, A, 83, 404 ; A . , ii, 376.l 8 Ann Report, 1909, 219.l 9 E. Rutherford and B. Boltwood, Mwn. Manchcster Phi,!. Soc., 1909, 54, [vi], 1 ;au Mnic.Curie and A. Debicrne, Compt. rend., 1910, 150, 386 ; A . , ii, 251.A., ii, 175.Hon. 11. J. Gtrutt, Proc. Roy. Soc., 1910, A, 84, 379; A,, ii, 1023RADIOACTIYLTY. 263used in the last investigation, calculated from the rate of pro-duction of helium and the quantity of helium in the mineral, arerespectively 250 and 280 million years. As certainly some of thehelium escapes, the real ages must exceed this.22 But severalexamples of the Archean rocks show a higher ratio of helium tothorium and uranium than thorianite,23 a minimum age of 700million years being indicated by this method for certain sphenes.Minerals like zircon and sphene contain hundreds of times asmuch helium as the average for the rocks in which they are con-stituents, so that the whole of the contained helium must have beengenerated since the consolidation of the rock and the separation ofthe mineral.The minimum ages for three other minerals foundby these methods were, in millions of years, (1) sphzrosiderite(Oligocene), 8.4 ; (2) hzematite (eocene), 31 ; (3) hzematite (carbon-iferous limestone), 150. I n explanation of the anomalous case ofberyl, which contains helium out of all proportion to its radioactiveconstituents, it has been suggested that the helium is derived fromradium or ionium initially deposited with the mineral, which, inthe absence of its parent element, has completely disintegrated.Distinct traces of helium have been found in many minerals, notappreciably radioactive, such as castorite and tourmaline, in additiont o beryl, whilst the strongly radioactive minerals formed in thecontemporaneous eruptions of Vesuvius, for example, cotunnite, theradioactivity of which is due to radium-D and its products withoutradium, do not contain helium.In the recent strongly radioactiveminerals, carnotite and tobernite, helium in minute quantity hasbeen detected, but in autunite the amount in certain specimens isnot detectable.24 Autunite is interesting, also, since it containspractically no lead, and because its radium-huranium ratio isabnormally low .25An examination 01 the helium content and the radium-buraniumratio of several specimens of Portuguese autunite showed that bothquantities vary very much in different specimens.I n one specimen,specially chosen on account of its fresh and unaltered appearance,no helium was found, although the amount formed in only thirtyyears could have been detected, whilst the radium ratio was thehighest of all those examined, being 70 per cent. of the equilibriumamount. I n the other specimens helium was found, in one case inconsiderable amount, corresponding with 70,000 years’ accumulation.As the helium increased, however, the radium ratio decreased to22 Ann. &port, 1909, 250.2y Hon. R. J. Strutt, Proc. Roy. SOC., 1910, A, 83, 298, and A, 84, 194; A., ii,24 A. Piutti, LB h!cm?iecm, 1910, 7, 146, 178 ; A , , ii, 677, 767,175, 920.Ann. Report, 1909, 250, 260264 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.a minimum, and then again rose more slowly, suggesting, i f thefew specimens so far examined are representative, that theformation of Portuguese autunite is a process now in actualoperation, and that the crystals when first deposited contain theradium, but not the ionium associated with the uranium in theparent mineral.The radium present, in consequence, decays forthe first few thousand years after the formation of the crystalsuntil a minimum is reached, when fresh begins to be suppliedfrom regenerated ionium.26 Private information, supplied by theowners of Portuguese autunite mines, makes it clear that mostinteresting geological processes are there in full operation a t thepresent day. For the whole mass of material treated, theRutherford-Boltwood ratio of radium to uranium is found to holdaccurately.I n selected crystals, however, an exceedingly lowvalue for this ratio is often found, whilst the materialof the rock walls in which the veins of autunite occur sometimescontain a relatively high content of radium and no chemicallydetectable quantity of uranium. The case is probably completelyanalogous to the superficial coating of the pyromorphite of Issy-1’EvGque with radium, which has been connected with the existenceof an autunite deposit in the neighbourhood.27 I n both cases,however, it is probable that it is not the radium which is separatedby the agency of percolating water, but its parent, ionium. Amillion years hence such rocks might well contain detectablequantities of helium and no ra,dioactive matter.The presence of helium to the extent of 0.17 volume per cent.ininflammable natural gas (83.6 per cent. hydrogen, 4.4 per cent.methane, 12 per cent. inert residue), issuing from the carnallitebeds of Leopoldshall, has suggested that the origin of the gas maybe due to the decomposition of water by radioactive impurities inthe carnallite. The oxygen would go to oxidise the ferrous chloridepresent as rinnite (FeCl2,3KC1,NaC1). The well-known blue rocksalt found in these mines may be due to the action of the rays ofthe radioactive matter on the sodium chloride.28@-Rays.Homogeneous fl-Rndiation.-Foremost in the work on P-rays mustbe placed a notable advance, bearing out the working theory beforealluded to,29 that in any single disintegration only one type of&radiation is expelled, which, like the a-radiation, is homogeneous26 F.Soddy, Le Radium, 1910, 7, 295 ; A . , 1911, ii, 6.2i Ann. Report, 1909, 260.28 Ernst Erdmann, Ber., 1910, 43, 777; A . , ii, 376.29 Ann. Report, 1909, 241RADIOACTIVITY. 265as regards initial velocity of expulsion, and is exponentially absorbedby matter. If a beam of 8-rays, after passage through a slit, isdeviated in a suitable magnetic field and allowed t o fall on aphotographic plate, the resultant image will be like a continuousspectrum, if the rays are perfectly heterogeneous, and like a linespectrum if they are composed of several types of distinct homegeneous bundles of rays. The 8-rays from the active deposit ofthorium gave a photograph having a single sharp line correspondingwith the hard &rays of thorium-D, and another corresponding withthe soft 8-rays of thorium-A, in addition t o others due to very soft8-rays, so feebly penetrating that they cannot be differentiated froma-rays in ordinary absorption measurements.A radiothoriurn pre-paration showed, in addition, a previously unrecognised very soft8-radiation, due to thorium-X, which separate experiments showedwas about three times as readily absorbed as the @-rays ofthorium-A.30 Radium-E gave one not very sharp line, whilstmesothorium-2 showed, apart from four lines due to extremely soft&rays, only a broad band, indicating that its penetrating &rays,like those of radium-C, are complex.It is perhaps natural thatthe most definite results in favour of distinct types of &rays shouldfirst be obtained for an active deposit where no absorption takesplace in the radioactive matter itself, for the heterogeneity of&rays from a thick layer of substance is not inconsistent with aninitial homogeneity subsequently modified by absorption in thematerial. Thus the @-rays from a thick layer of radium-E havebeen shown by magnetic deflexion experiments to be heterogeneous,and different bundles of rays ca.n be sorted out of widely differentpenerating power, the absorption coefficient [p(cm.)-lJ 31 varyingbetween 13 and 62.5. Yet as a whole the radiation is exponentiallyabsorbed [p(cm.)--l= 43].32 This result supports the view that theexponential law of absorption is indicative of heterogeneity of therays with a certain distribution of velocity among the constituentsof the beam, rather than the older view that because the rays areexponentially absorbed therefore they are homogeneous.33 At thesame time a repetition of the experiments which led before to theconclusion that homogeneous 8-rays, obtained by magnetic sorting,are linearly absorbed, with more strictly homogeneous rays, in a5o 0.von Baeyer and 0. Hahn, Physikal. Zeitsch., 1910, 11, 488 ; A,, ii, 566 ;0. Hahn and L. Meitner, ibid., 493 ; A., ii, 566.31 In view:of the universal use of the symbol A to express radioactive constants, infuture in these Reports the symbol p will be chosen to cxpross absorption coefficients,according t o the custom on the Continent.32 J.A. Gray and W. Wilson, Phi2. Mag., 1910, [vi], 20, 870 ; A., ii, 1022.31 Ann. Report, 1909, 240 ; W. Wilson, Physikal. Zeitsch., 1910, 11, 101 ; A,,ii, 175266 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.vacuum where no scattering occurs, showed two entirely differentcases, according as to whether aluminium or platinum was employedas absorbent. For the first, the curve was neither linear norexponential, but showed two opposite inflexions, which would, withless refined magnetic sorting, be smoothed out to give a curveapparently linear. Platinum, however, after the first 0.001 cm.,for which the curve was very steep, showed for homogeneous &raysa strictly exponential curve.34 Again, after passage through 0*001cm.of platinum, homogeneous &radiation is exponentially absorbedby aluminium, and the view is taken that exponential absorption isindicative of a completely scattered radiation.35 The velocity ofhomogeneous &radiation is slightly but definitely diminished bypassage through aluminium and glass, whilst from platinum the raysemerge with a considerable range of velocity, for the most part,but not altogether, less than initially. The “absorption” of&rays is, however, due to the complete stopping of a fraction ratherthan to the retardation of the whole beam. For a heterogeneous/?-radiation the velocity of the rays after transmission through anabsorbing plate is apparently unaltered, owing to the preferentialabsorption of the less penetrating rays, whereby the retardation ofthe transmitted rays is masked, but with homogeneous B-rays theretardation is now well established.36 The greatest reduction ofvelocity yet observed is 21 per cent., but owing to the high velocityof the rays and the consequent increase in their apparent mass,this diminution in the velocity corresponds to a reduction of energyof 77 per cent.Over this range the absorption coefficient increasedfrom 4*8(cm.)-1 t o 35’7(cm.)-1. Thus, although the reduction invelocity is small, the effects produced on bhe absorption curves areof great importance.The scattering of homogeneous &rays was found to bear out atheory of the nature of the action which has been proposed.37 Adeduction from the results was that in all the atoms examined thenumber of electrons is three times the atomic weight on the viewthat the positive electricity, assumed to be present, is uniformly dis-tributed, not: concentrated in an electronic condition.The power of diff erenb substances to reflect &rays increases withthe velocity of the rays ( H p from 1000 to 3000), and thendiminishes again, although the ratio of the reflecting power ofdifferent substances is not influenced by the velocity of the rays.34 J.A. Crowther, Proc. Cantb. Phil. SOC., 1910, 15, 442 ; A., ii, 672.35 J. A. Crowther, Proc. h y . Soc., 1910, A, 84, 226 ; A., ii, 918.37 Sir J. J, Thomson, Proc, Canzb, Phil, Soe., 1910, 15, v,W. Wilson, ibid., 141ItADIOAC1'1 VITY.267The point of maximum reflexion corresponds with an absorptioncoefficient of about 2 0 ( ~ m . ) - l . ~The relative ionisation produced in different gases by brays, also,is uninfluenced by the velocity of the rays, the ratio for differentgases being the same with the &rays of actinium it9 with the muchmore penetrating &rays of uranium.39Although the work on homogeneous &rays has resulted in notabledefinite advances, much still remains to be done before the verycomplex questions involved are fully cleared up.A bSOrpti07L of t h e /3-Rays.40-Experiments with liquids haveshown that the 8-rays of uranium-X and radium are absorbed bythe component atoms in a purely additive manner. Neitherallotropy nor isomerism influence the absorption, and two liquids,which react chemically, absorb to the same extent before and aftermixing.The absorption by the chemical elements is a periodicfunction of the atomic weight, the electronegative elements absorb-ing less than the electropositive. The absorption divided by thecube-root of the atomic weight gives a constant which is the samefor all the elements in the same natural group of the periodic table,but varies slightly with different groups.The A t o m k Cliarge of Electm'city.-So far no experimentalevidence for the existence of entities of negative electricity less inquantity than the charge on the hydrogen ion has been found, inspite of the immense variety of phenomena investigated. By thefurther study under improved conditions of the charged dust ofplatinum and silver produced by forming an arc between poles ofthese metals in air,*l values have been obtained differing widelyfrom the atomic charge, or multiples thereof, and in some casesfar below it.It is too early to discuss this result, which, if correct,is of capital importance.Emission of Electrons from t h e RZh.aZi-MetaZs.-The persistenceof this phenomenon to a feeble extent in total darkness, whichhas suggested the view that the action is analogous to the spon-taneous atomic disintegration of radioactivity, has been investigated.As an alternative, it seems more likely that the action may bedue to the diffraction of long waves round the edges of screens, andto heat radiation of ordinary temperature.42and W.Wilson, ibid., 866 ; A . , ii, 1022.A. F. Kovarik, Phil. Mag., 1910, [vi], 20, 849 ; A , , ii, 1021 ; A. F. KovsrikR. I). Kleenian, Prm. Roy. SOC., 1910, A, 83, 530 ; A., ii, 474.H. W. Schmidt, Physikal. Zeitsch., i910, 11, 262; A., ii, 378 ; W. A.Borodowsky, Phzt. Nag., 1910, [vi], 19, 605 ; A., ii, 375.'* Ann. BePrl, 1909, 235 ; F. Ehrenhaft, Wieiur Anzniger, 1910, x,42 L- DunoYer, am#. r e d . , 1910, 180, 335 ; A., ii, 253268 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.y-Rays.The ionisation produced by y-rays in electroscopes of the samevolume is known to vary considerably with the material out of whichthe electroscope is made, being greatest for lead. Provided thatthe wall thickness is sufficient to absorb B-rays completely, it hasbeen shown that the relative ionisations in different vessels are ameasure of the average .ranges of the B-rays generated by the7-rays in the metals concerned.This method of estimating theaverage ranges is independent of the amount of deflexion andscattering suffered by the P-ray. I n ordinary circumstances, leadabsorbs more than other mstals, weight for weight, but this is dueto the more zigzag character of the path of the B-ray in lead. Theaverage length of the real path of the B-ray, multiplied by thedensity of the metal, is greatest in lead, although the trajectory ismore entangled.43Lead has another advantage in the construction of y-ray electro-scopes, in that it is, of all metals, the least penetrated by thesecondary rays generated by the y-rays in surrounding objects.Provided that a thick lead electroscope is used, with the windowsand cork properly screened by lead, the absorption curve of theradium y-rays in lead is absolutely exponential from 1 cm.to 22 cm.,with the value of p(cm.)-l 0.50. The departures from theexponential form previously observed, which were supposed toindicate heterogeneity of the rays, are due to secondary rays enteringthrough the sides of the electroscope. The absorption curves overthe initial thickness up to 1 cm. of lead, or its equivalent, are notexponential, but the variations are not due to initial heterogeneityof the beam, as the departures are in opposite senses with differen4metals and different experimental arrangements. With it pointsource of radium at the centre of a hemispherical ionisation chamber,with absorbing plates in the form of truncated hemispheres, thetheoretical absorption curve can be evaluated on the assumptionthat the y-rays are homogeneous, and are not scattered.For lead,the curve found agreed closely with the theoretical from the thick-ness sufficient to absorb P-rays onward, which is strong evidencein favour of the homogeneity of the y-rays of radium. However,there is other evidence against this view. The phenomenon of thehardening of the y-rays by passage through increasing thicknessof lead, whereby the penetrating power of the transmitted raystowards a lighter metal, such as zinc, is continuously increased,apparently without limit, although the absorption curves are alwaysstrictly exponential,, is strong evidence in favour of it continuousq3 W.H. Bragg, Phil. Mag., 1910, [vi], 20, 385; A., ii, 919RADIOACTIVITY. 269modification of the nature of the y-radiation by lead. As in thecase of the &rays, the problem arises as to how far a strictlyexponential absorption curve is indicative of homogeneity, althoughit must be remarked that the exponential law holds far more com-pletely for the y-rays than for the 8-rays. The studies before madeof the y-rays of uranium-X and radium have now been extendedto t_he two types of y-rays in the thorium series, from mesothorium-2and thorium-D, and for those of actinium4 or -D. The generalresult is t o show that the two thorium y-rays are extremely similarto those of radium4 both in penetrating power and in the ratioof the intensity of y- t o 8-rays.The y-rays of thorium-D are themost penetrating rays known, being a few per cent. more pene-trating khan those of radium-(?, while those of mesothorium-2 area few per cent. less penetrating. The y / P ratio of both types israther less than for radium-C, that of thorium-D being less thanthat of mesothorium-2. The y-rays of actinium are abnormallyhighly absorbed by lead, and in addition the absorption curve isnot exponential, showing two sharp points of inflexion at thickness0.3 cm. and 0-85 cm., although f o r other metals the curves arequite exponential. The absorption coefficient is about twice thatof radium-C for metals other than lead, and varies from seven tothree times greater for lead, whilst the y / 8 ratio is only fromthirteen to eight times as great, according t o the method of measure-ment.I n the latter respect therefore actinium is more analogousto uranium than to radium and thorium. All this workemphasises how little connexion there is between the properties ofthe y-rays and those of the 8-rays which always accompany them,and has strengthened the view that the two types are not inter-dependent. Indeed, there is far more connexion between theproperties of the y-rays and those of the a-rays which precede andfollow them in the disintegration series than with those of the 8-rayswhich accompany them. With the exception of actinium, the morerapid the change, the more penetrating the y-ray emitted, as is thecase for the a-rays.44Secondary y-Rays.-When y-rays strike a plate of metd,‘‘ secondary ” y-rays, softer than the primary, are emitted fromboth sides of the plate, the “ incident” being always softer thanthe “ emergent ” secondary rays.T‘he “ secondary ” rays appear toconsist merely of scattered and softened primary rays, and shows nosudden break in properties from the primary, there being a gradualsoftening the more the secondary radiation departs in direction fromthat of the primary. The lighter elements produce more secondaryradiation than the heavier elements. As the thickness of the44 F. and W. M. Soddy and A. S. Russell, Phil. Mag., 1910, [vi], 19, 725 ; A.,ii, 474 j A .S. Russell and F. Soddy, ibid., 1911, [vi], 21, 130270 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.plate is increased, both the primary and the emergent secondaryrays are hardened. These results have been held to support theview that the primary rays are heterogeneous, the softer radiationbeing more scattered than the harder, so that the emergent primarybeam is hardened by passage through metals.45 Thus the evidence,as in the case of the &rays, is conflicting, and much still remainsto be explained.Much interesting work46 has been done on the homogeneoussecondary X-rays. When X-rays fall on a metal, for example, tin,a characteristic secondary " tin " X-radiation is generated, providedthat the primary rays possess a sufficient degree of hardness.Thedegree of hardness necessary increases with the atomic weight ofthe metal. Characteristic homogeneous secondary X-radiations haveso far been obtained from the elements included between iron andantimony, the former being seventy times more easily absorbed thanthe latter. It does not seem possible to produce a primaryX-radiation sufficiently hard to excite the characteristic secondariesof the elements heavier than antimony. The existence of thesecharacteristic radiations explains the great absorbing power of heavyvapours, like ethyl bromide and iodide, for X-rays, which was pre-viously thought to be anomalous, the heavy atoms of the gas beingexcited to give their characteristic radiation with greatly increasedabsorption of the primary rays and ionisation in consequence. Nosuch phenomena have so far been observed with y-rays, and theyform, with the polarisation of the X-rays, the two chief argumentsin favour of a wave-theory and against the corpuscular theory ofthe nature of the X-rays.On the other hand, if the argument isconfined to the y-rays alone, the corpuscular theory offers a fairlycomplete and reasonable view of their properties, and has proved ofthe greatest service in simplifying the many complex phenomenaencountered.47The uolz Schweidler Va&ation.-Attempts have been made tosettle between the two hypotheses by comparing the von Schweidlervariations of the y-rays due to the irregularity of the individualatomic disintegrations. I f the wave-front possesses a heterogeneousstructure, as it must have on the corpuscular hypothesis but noton the wave theory, a second von Schweidler variation would besuperimposed on the first, which would come the more into evidence45 D.C. H. Florance, Phil. Mag., 1910, [vi], 20, 921.46 C. G. Barkla, ibid., 370 ; A., ii, 920 ; R. T. Bcatty, Proc. Cam6. Phil.Soc., 1910, 15, 416; A., ii, 674 ; R. D. Kleeman, Proc. Roy. SOC., 1910, A ,84, 16 ; A., ii, 567 ; J. L. Glasson, Proc. Camb. Phil. Soc., 1910, 15, 437 ;A., ii, 674; J. C. Chapman and S, H. Piper, Phil. Mag., 1910, [ivJ, 19, 897;A , , ii, 567.47 W. H, Bragg, Phil. Nag., 1910, [vi], 20, 385 ; A., ii, 919RADIOACTIVITY. 27 1.the narrower the pencil of rays employed. A series of experimentson these lines supported strongly the view that the wave front isstrongly anisotropic, although, of course, it does not decide whetherthe rays are propagated along lines or narrow cones.48 The fact thatin all probability the y-rays do not ionise directly, but by meansof the secondary B-rays they generate, and the possibility that inaddition to the other variations the number of pairs of ions producedby the individual y-ray in the gas is also subject to variations of asimilar kind, makes the interpretation of such experiments verydifficult and uncertain.49Th ermo-radioactivity.The heat evolved by pitchblende, containing 64 per cent.ofuranium, has been found to be 6.1 x 10-5 calories per hour pergram, which is about 30 per cent. higher than the rate calculatedfrom the kinetic energy of the a-particles expel1ed.s With the verysensitive calorimeter before described, the direct heating effect ofthe a-rays from radium8 has been clearly detected, the B- and y-raysnot producing any appreciable action.51 It has also been established,with the same instrument, that when a phosphorescent salt is mixedwith a radium preparation, the same amount of heat is evolvedas in its absence, showing that by the intermediate transformationof the energy of the rays into light no alteration is brought aboutin the amount of heat ultimately produced.62 By means of adifferential air calorimeter of glass, the difference between the heatenergy evolved from a zinc sulphide preparation exposed to a-rays,bare and covered with black paper to absorb light, was found tobe about 1.5 per cent.of the total heat evolved. This gives a roughestimate of the fraction of the energy of the a-rays converted intolight by zinc su1phide.MRadioactive Recoil.The atomic mas3 of the recoiled atoms of radium-B, which carrypositive electric charges, has been determined by the measurement ofthe electrostatic and electromagnetic deflexion of the atom. Thevalue found for Hp, which is equal to mule, in the magneticdeflexion experiment was twice that for the a-particle, indicating,Edgar Meyer, Sitz~cngsber. K. AkcuE. IYiss. Berlin, 1910, 32, 647 ; JaliIZadwaktiv. Mektronik, 1910, 7, 279 ; A., ii, 673.49 E. von Schweidler, Phywikal. Zeihch.. 1910, 11, 225, 614 ; A . , ii, 376, 766.H. H.Poole, Phil. Mug., .1910, [vi], 19, 314 ; A., ii, 176.Ann. &port, 1909,245 ; W. Duane, Compt. rend., 1910, 151, 471 ; A., ii, 862 W. Duane, Compt. rend., 1910, 161, 379 : A., ii, 816.09 E. Marsden, Proc. hj. Sac., 1910, A, 88, 648 ; A., ii, 565,b.6272 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.since the momentum mu of the recoiling atom must be equal tothat of the a-particle, that the recoiling atom carries a singlepositive charge. From the combined deflexions, the velocity of therecoiling atom was found to be 3.23 x lo7 cm. per second, and itsmass, 194 (H=l). The difference between the latter number andthe value 214-5, calculated by subtracting from the atomic weight ofradium three times that of helium, is not significant, as the experi-ments do not permit of a high degree of accuracy.54The amount of product recoiled in an a-ray change, for example,radium-A from the emanation, or radium-B from radium-A, is muchgreater than the amount in a &ray change, for example, radium-C2from radium-C,, as is to expected.But it seems that even in arayless change, or one in which only a very feeble B-ray is expelled,as that of radium-B, a perceptible amount of the product (radium-C,)is recoiled, which varies capriciously in different experiments Therecoiling radium-C, atom, which carried no charge, possesses apenetrating power about one-fortieth of that of the recoiledradium-B atom. It is probable that in this case mechanical dis-turbance, due to the violent disintegration of radium-C, bringsabout the projection of neighbouring radium8 atoms, as the energythey possess is far greater than is to be expected if they were reallyrecoiled during the disintegration of radium-B.55Some evidence has also been obtained that recoiled atoms ofradium-B can be scattered by a reflector and deposited on a surfaceout of the direct line of fire of the stream, but the possibility thatatoms can be mechanically removed by the disintegration ofneighbouring atoms, so simulating a recoil phenomenon, makes theinterpretation of the results difficult.56The range of radium-B recoiling from radium-A is about 400times less than that of the a-particles of radium-A, or about a tenthof a millimetre of air at normal pressure.A single gold leaf, of0-08 p thickness, would thus completely stop the recoiled atoms.I n hydrogen the range is about six times that in air.Someinteresting experiments were done with plates which, afterimmersion in the emanation, were silvered to different extents. Acoating of silver 20 pp in thickness stopped the recoil completely,while 10 pp allowed some 60 per cent. of the recoiling atoms to passthrough. I n the distribution upon surfaces of the active depositfrom the emanation, recoil phenomena play an important part,s4 S. Rum and W. Makower, Phil. Mag., 1909, [vi], 20, 875 ; W. Makower andE. J. Evans, ibid., 882; A . , ii, 1022, 1023.b6 W. Makower and 8. RUSS, ibid., 1910, [vi], 19, 100 ; A . , ii, 91 ; S. RUSS,Le Radiwm, 1910, 7, 93 ; Mem. Mamhester Phil.Xoc., 1910, 54, No. viii, 1 ; A.,ii, 475.W. Makower and 8. Ruas, Mem. Jhchestcr Phil. Soc., 1910, 55, No. i, IR hDIOACTIVTTY. 273especially in gas at low pressure. I n the case of radium-D, which,owing to its extended life period, possesses a radioactivity too feebleto be detected in ordinary circumstances, there is some evidence thatit may be possible to follow its recoil from radium-C, by means ofthe ionisation the projected particles produce in a gas at lowpressure.57Influence of Temperature o n Radioactive Change.Many of the effects which were supposed to indicate an alterationin the rate of change in the active deposit of radium at hightemperature have received a satisfactory elucidation, and thequestion may now be considered settled.The hard y-rays showpractically no change when, for example, a radium preparation ina quartz tube is heated in an eIectric oven to 1 2 0 0 O to 1300°, eitherduring the heating or subsequently. But the &rays show a curiousand complex sequence of variahions, which are such as can beaccounted for by changes in their absorption by the preparationitself. The first effect of the heating is to liberate the occludedemanation and to gasify the products radi~m-~4, -B, and -C fromthe preparation, causing a lessened absorption and consequentsudden incre?se of P-radiation. On cooling, the products, all exceptthe emanation, are suddenly absorbed again by the preparation,with a consequent sudden return of the @radiation to its initialvalue.Three hours afterwards, a new set of products is producedon the walls of the containing tube from the liberated emanation,which causes the &radiation gradually to return to its higher value.Then over a period of three weeks, the liberated emanation decays,while fresh is produced within the solid preparation, producing agradual decay of the P-rays to their initial value. The conclusionis that so far as experiments have yet been carried, temperatureproduces no real change in the rate of atomic transformation.58The Uranium-Radium D i s k t egration Series.A series of measurements, giving the relative proportion of B-rayscontributed by the different constituents of uraninite in a cylindricalelectroscope 40 cm. high and 40 cm. diameter, gave as the resultthat uranium-X (hard rays only) contributes about one-third,radium-B and -C about onehalf, and radium-E about 10 per ~ e n t .5 ~Uranium-X.-A new determination of the radioactive constantof uranium-X gave a result about 10 per cent. less than the value57 L. Werteiistein, Compt. rend., 1910, 150, 869 ; 151, 469 ; A., ii, 476,816.58 H. W. Schmidt and P. Cermack, Physikal. Zeitsch., 1910, 11, 793; A . ,59 S. J. Lloyd, J. Physical Clwn., 1910, 14, 509 ; A., ii, 765REP.-VOL. VII. Tii, 918274 ANNUAL REPORTS ON THE PROGRESS OF' CHEMISTRY.previously used, namely, 0.0282(day) -1. This makes the periodof average life 35.5 days, and that of half-change 24.6 days. Thevalues obtained from the decay curves of the y- and &rays, thefirst over a period of eight months and the second over fourteenmonths, were identical, both types of rays decaying normally tozero. The uranium-X was prepared from 50 kilos.of uraniumnitrate, and the observations of the y-rays were continued untilthey were reduced to about 1/7OOth, and of the &rays to1 / 100,000th of their initial value.60 The further study of theseand similar preparations to determine whether a, feeble a-radiationdeveloped as the /3-radiation decayed, either concomitantly or sub-sequently, as is to be expected if ionium is the product of thedisintegration, has given a completely negative result. A feebleconstant a-radiation remains after the penetrating radiation hascompletely decayed, but it is present from the start, and is duet-o impurities separated from the uranium.The conclusion fromthese experiments is that, if ionium is the direct product ofuranium-X, its period of average life must be greater than 35,000years as a minimum, which agrees with the experiments on theabsence of growth of radium in uranium solutions (p. 275).Neither has any indication of the growth of actinium from thesepreparations yet been obtained, but actinium in minute amount ispresent from the start as an impurity.61Evidence has been obtained in the adsorption of uranium-X,by precipitating barium sulphate in a solution of uranium nitrate,of the existence of a definite partition coefficient between theabsorbent and the solution. Experiments carried out by pre-cipitating different, amounts of barium sulphate in similar solutionsunder exactly the same conditions showed that' the distributionobeys the law C/C'~ =constant, where c and C are the concentrationsof the uranium-X in the solid and liquid phases respectively, and nis a constant.This relation probably only holds for the initial dis-tribution immediately after precipitation, as, no doubt, on keeping,the uranium-X would diffuse into the barium sulphate particles,lessening the surface concentration, and enabling the bariumsulphate t o withdraw further amounts of uranium-X from thesolution. 62The following method of separating uranium-X from uraniumnitrate has been recommended. Soot, freshly obtained by burningnaphthalene, is stirred into the acetone solution, and then extractedwith hydrochloric acid.Iron is added to the extract, and pre-cipitated with ammonium carbonate in excess. The uranium-X is6o F. goddy and A. S. Russell, Phil. Mag., 1910, [vi] 19, 847 ; A., ii, 568.''l F. Soddy, ibid., 20, 342 ; A.. ii, 921.( j Z A. J. Evrry, Trans., 1910, 97, 196RADIOACTIVITY. 275freed from the iron precipitate by dissolving it in concentratedhydrochloric acid, and extracting the solution with freshly distilledether saturated with hydrogen chloride, when the uranium-Xremains dissolved in the aqueous layer.63The statement occurs in various places that uranium-X andthorium are chemically analogous and cannot be separated, butno detailed researches have been published.64 This would explainat once the remarkable fact commented on last year,65 that a traceof thorium sulphate added t o a uranium solution completelyprevents the adsorption of uranium-X therefrom by means ofcharcoal.It has been noticed that the short-lived radioactiveproducts are much more prone to separation by adsorption thanthe long-lived. The reason for this is clear, since when quantitiesof different radioactive products of similar intensity of radioactivityare compared, as is usually the case, these quantities are p r eportional to the periods of the products. I f , now, a given quantityof an adsorbent is able t o absorb the same absolute quantity oftwo different radioactive products, the adsorption may be prac-tically complete for the one product if it is short-lived, andinappreciable for the other if it is long-lived, although the actnalmasses of each adsorbed is the same.If there is also present anelement either not radioactive, or, if radioactive, of long period,which has a chemical nature entirely analogous t o that of theshort-lived product, it follows that a mere trace of it will besufficient entirely to stop the adsorption of the short-lived product.flGThe Relation between Uranium a d Radium: 1onium.-The rateof growth of radium in the purified uranium solutions, which wasbefore stated to have increased during the fourth year from pre-paration, according to the square of the time, has not beenmaintained. There was an undetected error in the measurements.It is probable that the undoubted growth of radium, so farobserved, is due to a trace of ionium initially present, and thatthe growth from uranium has not yet appreciably started.Thisincreases the minimum estimate of the period of average life ofionium t o at least 35,000 years, if there is only one long-livedintermediate body in the series, and the extended period is inagreement with the experiments on the absence of a growth ofa-radiation from uranium-X already described.67 The variations63 S. J. LIoyd, J. Physical Chem., 1910, 14, 509 ; A . , ii, 765.64 B, Keetnian, Jahrb. Rndioaktiv. Elcktronik, 1909, 6, 265 ; A., 1909, ii, 852 ;8b Ann. Report, 1909, 262.66 F. Soddy, Trans., 1911, 99, 72.67 Ann. R ( p r t , 1909, 262 ; F. Soddy, Phil. Mag., 1010, [vi], 20, 340 ; A . , ii,W.Marckwald, Ber., 1910, 43, 3421 ; A , , 1911, ii, 8.921.T 276 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in the uranium-radium ratio in autunite and thorianite have beenre-examined.68 Some of the results with Portuguese autunite havebeen referred to under Helium (p. 263). Various specimensexamined showed a radium ratio from 70 to 44 per cent. of theequilibrium ratio, whilst a specimen from Autun, France, hadonly 27 per cent., the lowest yet recorded. The ratio f o r thorianitewas found to be only slightly greater than that for Joachimsthalpitchblende. It is probable that the extended life period of ioniumwill account for all these departures, and that even in Joachimsthalpitchblende the radium ratio may be slightly lower than the trueequilibrium ratio, owing to the mineral not being sufficiently old.The small amount of helium in this mineral is evidence that itmust be, geologically, a recent formation.It is interesting to note that the exact law of radioactiveequilibrium is A,x, = X A ( l t A + x, + x, + .. . ltN), where x,, x,, x,, etc.are the quantities of the successive members of a disintegration series,and A,, A,, A,, etc., their radioactive constant^.^^This relation becomes identical with the usual approximaterelation ANxN = AAxA when the periods of the products are negligibleby comparison wit'h that of the parent element. It shows thateven were the period of ionium a million years, its effect on theequilibrium ratio of radium to uranium would be less than a tenthper cent.I n a very complete chemical investigation of the '( hydrate "fraction obtained from the working up of ten tons of Joachimsthalpitchblende for radium, which contained the actinium and ioniumof the mineral together with rare-earths, the ionium followed all thereactions of thorium, and was separated with this element from allthe other constituents.For details, the original work must beconsulted. Numerous fresh attempts to separate the ionium fromthorium, including various fractionation processes and the heatingof the oxide in the electric arc, failed completely in their purpose,as have many independent attempts previously.70Actinium.-In the same research, actinium, which is known t ofollow the reactions of lanthanum very closely, was found to standchemically between lanthanum and calcium.It was observed thatin presence of ammonium salts neither ammonia nor ammoniumoxalate precipitate actinium completely, but in presence ofmanganese it can be precipitated from the basic solution as aAnn. Izeport, 1909, 260 ; F. Soddy and Miss R. Pirret, Phil. Mag., 1910, [vi],20, 345 ; A., ii, 922; A. S. Russell, Natzwe, 1910, 84, 238 ; compare Mme. Curie,Radionctivitd, 11, 441.69 H. Mitchell, Phil. Mag., 1911, [vi], 21, 40.70 C. Auer von U'elsbach, Sitzungsbm. K. Akad. Wiss. Wien, 1910, 119, [iia],1 ; A., 1911, ii, 7RADIOACTIVITY. 277manganate, which proved to be a reaction of great value in itsseparation. This piece of work was carried through withoutrecourse to the usual method of adding the element most nearlyallied chemically to the radioactive substance and then separatingthem together, in order the more completely to elucidate thechemical nature of the extremely complicated mixtures treated.Indications of new non-radioactive elements were obtained.,4 ctinium-B.-Further evidence of the dual character of thisproduct, shown by the slight difference of range of the a-particlesemitted, has been obtained, the most important being that thescintillations, examined in a gas over the range of increasingpressure necessary to cause the a-particles just not to reach thescreen, disappear less abruptly than in the case of a substance likepolonium, known to give it homogeneous set of a-particles.71RacFium.-Foremoat in the work on radium is its isolation inthe elementary state as metal.About one-tenth of a gram ofperfectly pure radium chloride was electrolysed with a mercurycathode until the solution contained less than 10 per cent. of theinitial radium. The amalgam of radium, which was fluid, whereasparallel experiments with barium chloride had given a partly solidamalgam, was dried and cautiously ignited in an iron boat in acurrent of specially purified hydrogen a t reduced pressure. Whenthe temperature reached 400°, the amalgam became solid. A t 700°no more mercury volatilised, and the boat contained a brilliantwhite metal, which melted sharply a t about 700°, volatilisingappreciably a t the same temperature. Thus, in volatility andfusibility, radium resembles calcium rather than the much lessfusible and volatile barium, and it is possible that sublimation ina, vacuum may serve t o separate radium from barium.Radiumbehaved as is to be expected of an alkaline-earth metal, dissolvingin water with energetic evolution of hydrogen, and tarnishingrapidly in the air with the formation, probably, of the nitride.Its radioactive behaviour was also normal, the penetratingradiation from the metal, sealed in a glass tube, being generatedaccording t o the law of the production of the emanation.72Another interesting attempt to isolate radium from a mixture ofthe barium and radium azoimides, by careful heating in a " melting-point tube" to 185-250O in a perfect vacuum, yielded a shining,metallic mirror, containing the greater part of the radium employed,which behaved in the same way as metallic barium, appearing toform the nitride in moist air with even greater readiness.73 These71 Mlle.L. Blanquies, Compt. rend., 1910, 151, 57 ; Le Radium, 1910, 7, 159 ;A., ii, 768.72 Mme. Curie and A. Debierne, ibid., 523 ; A., ii, 816,73 E. Ebler, Ber.,gl910, 43, 2613; A., ii, 1024278 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.advances bring to a fitting consummation the long series ofresearches which began with the recognition of radium as a newmember of the alkaline-earth famiIy of elements, but, as was tobe expected, do not! add anything new on the radioactive side, forthe existence of all the radioactive properties of uranium unmodifiedin the metallic state has long been known.A careful estimation of the radium in all the by-products fromthe extraction of radium from 10 tons of Joachimsthal pitchblende,showed that there was present in all only 0.26 gram, of which two-thirds was present in the unattacked residue from the sodaextractions, and about onequarter in the lead products.74Radium Emanation.-Bunsen’s method of determination of thedensity of a gas, by its velocity of escape from a small hole in athin partition, has been applied to radium emanation, mixed withfrom 5 to 200 times its volume of foreign gas at a pressure of about0.01 mm.of mercury, the vessel into which the gas escaped beingkept continuously exhausted by a rotary mercury pump. Witha mixture of argon and oxygen under these conditions, each gasbehaved as if alone present a t its partial pressure, and for theemanation the amount of foreign gas present exerted no influenceon its rate of escape.The results, compared with those obtainedwith argon and oxygen, gave a value for the molecular weight ofthe emanation of about 220, the experiments not varying morethan 2 or 3 per cent.75The densitv of the emanation has been determined directly bymeans of the quartz micro-balance before described.76 Althoughthe quantities of emanation employed were almost infinitesimal, inno cam exceeding 0.1 cu.mm. volume a t atmospheric pressure, andof weight of the order of one-half a micregram, consistent resultswere obtained for the molecular weight of the emanation, lyingbetween 216 and 228, wit.h a mean value 220.The volume of theemanation was calculated from the volume in equilibrium with1 gram of radium (0.601 cu.mm.) previously found.77 Both of theseresults and that already given on the molecular weight of radium-B(p. 272) bear out fully the method of calculating the atomicweights of the members of the uranium-radium disintegration seriesby the subtraction from the atomic weight of uranium or ofradium the known number of helium atoms expelled in theirfor mat ion.A new determination of the period of the emanation, both bymeans of the P- and y-rays from a quantity in a sealed tube, and7* Helene Souczek, Sitzzcngsber. K. Akad. Wiss. Wien, 1910, 119, [iia], 371.75 A. Debierne, Conzpt. red., 1910, 150, 1740; A ., ii, 675.77 Sir W. R.amsay and R. W. Gray, Compt. rend., 1910, 151, 126 ; A . , ii, 767.A m . Xeport, 1909, 267RADIOACTIVITY. 27 9by means of the a-rays, the emanation being enclosed in an air-tightionisation vessel, gave, in five determinations by each method,results consistent t o 1 per cent. The period of average life is5-55 days, and of half-change, 3-85 days. The radioactive constant,A(hour)-l, is 0.00751. I n these experiments, the concentrationvaried over a range of 2 x loll. I n single experiments, theexponential decay continued for three months, over a decay to oneten-millionth of the initial quantity, so that no more completeproof could be desired of the absolute independence of the ra.tcof radioactive change upon concentration.Among other investigations of interest ib connexion with theuse of the emanation in the estimation of radium,'IB some resultshave been obtained which throw light on the progressively diminish-ing rate of production of emanation from a solution in which theradium has been freshly precipitated, which has raised the questionwhether an intermediate body, " radium-X," exists in the series.Heating a solution in which the rate of production had diminishedwith time, enormously increased the amount of emanation evolved,showing that the emanation was generated its usual, but accumu-lated in, and was not evolved from, the cold liquid.This isascribed to the slow formation of an invisible precipitate of non-emanating radium sulphate, which re-dissolves when the solutionis heated.79 The formation of other precipitates in a solution con-taining radium and barium does not much affect the amount ofemanation evolved, but sodium carbonate and sulphuric acid causea notable diminution, due to the precipitation of the radium.Stirring and heating a solution in which radium and bariumsulphate have been precipitated causes the radium again to gointo solution, so that a radium solution after barium sulphate hasbeen precipitated in it, but not removed, may recover its initialpower of evolving emanation.80Experiments on the release of emanation from various saltscontaining radium by heating have shown that the same fractionis retained whether the salt is maintained at the high temperatureor heated to it for only a short time before the extraction.Thisfraction, which is a function of the temperature only, not of thetime of accumulation, is constant for any given preparation, butvaries widelg with different preparations, being less for impurepreparations than for those containing barium and radium only.With minute quantities of pure radium chloride, it was found thatthe material was chemically changed by the heating, becoming78 W. Duane and A. Laborde, G'ompt. rend., 1910, 150, 1421 ; Lt! Badizrm, 1910,7, 162 ; A., ii, 676 ; lime. Curie, Le IZadiunz, 1910, 7, 65 ; A., ii, 476.L. Kolowrat, Le Radiuw~, 1910, 7, 157.eo S. J. Lloyd, J. Physical Chcn~., 1910, 14, 476 ; A , , ii, 568280 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.insoluble and no longer evolving its emanation completely at thefusion temperature.81The absorption of the emanation by cocoanut charcoal, in thismethod of estimating the amount in the atmosphere? is nevercomplete? but the fraction absorbed was found to be the same forsolutions of different amounts of radium, up to 6 x 10-9 gram.The fraction absorbed diminishes as the velocity of the air streamincreases and with the time the experiment lasts, as though thecharcoal became superficially saturated.82 Other experiments havenot confirmed the great difference found in the temperature ofvolatilisation of the condensed emanation from glass and metalsurf aces respectively.83 I n this new work, almost.inappreciabledifferences? not greater than 4O, were observed.84Radium-D.-Numerous attempts have been made to concentrateradium-D (radio-lead) from lead, but without success,*j and thereis good reason for thinking that the two elements form a non-separable pair, of which so many cases now exist.The separationwould be a valuable one, if it were possible, as all the P-rays ofthe mineral due to the radium-E are a t present not utilised, thelead seprtrated having a P-activity not very much greater thanuranium. However, pure radium-D can be formed in minuteamount from the radium emanation by leaving it to decay in asealed tube. I n course of time this develops polonium or radium-F,which gives a-particles. By counting the number of scintillationsproduced by the a-particles emitted after a known time from asknown initial quantity of the radium emanation? the period ofradium-D can be determined.Five results by this method gavethe result 16.5 years (k0.5 year) for the period of half-change.I n the course of this work, it was found that a quantity ofradium-D deposited during a single day from a large quantity ofthe emanation developed the P-radiation due to radium-E regularlyand normally w&h the half-change period of five days. Whenradium-E is separated from a solution of radium-I) by precipitatingthe la<tter with barium sulphate, the &rays decay normally withthe same period. These results disprove the existence of an inter-mediate rayless product, radium-E,, in the series. Only oneproduct, radium-E, exists between radium-D and polonium, andthis gives P-rays, and has a period of half-change of 5-0 days.Radium-D is removed with radium from an old radium preparatione l L.Koluwrat, Le Radizm, 1909, 6, 321 ; 7, 266 ; A . , ii, 91, 1023.82 J. Satterley, Phil. Mag., 1910, [vi], 20, 778 ; A . , ii, 921.83 Aptn. Eeport, 1909, 254.85 H. Herschfinkel, Le Eadizcin, 1910, 7, 198 ; A., ii, 817.R. W. Boyle, Phil. Mag., 1910, [vi], 20, 955 ; A., 1911, ii, 6RADIOACTIVITY. 281by the precipitation of barium sulphate, leaving radium-B andpolonium in solution.86Polonium.-In the working up of some tons of residues ofuranium minerals, the polonium was obtained in a final con-centrated product, weighing 2 milligrams. It was estimated thatthe actual quantity of polonium present was 5 per cent.of thisweight, and corresponded with the amount in about 2 tons of goodpitchblende. The product gave a spectrum showing several newlines, and it is proposed t o see if these alter in intensity anddisappear from the spectrum as the polonium disintegrates. Bythe same tests it is hoped to see whether the spectrum of lead,which, although not altogether absent in the preparation initially,was very feeble, increases in intensity as the polonium decays. I nthe course of a year or two the greater part of the polonium willhave disintegrated, and the results of the subsequent spectroscopicinvestigation will be awaited with interest.87 Old polonium pre-parations decay regularly and completely with the normal period,showing that no further products possessing detectable activityexist.8s There can be little doubt that the product will prove t obe lead.What the end products of the thorium and actiniumseries are there is a t present no means even of guessing.The Thorium Series.Mesothoriurn.-Preparations of mesothorium more concentratedthan pure radium salts, as regards the intensity of the penetratingrays, have, during the year, been prepared by a secret process frommonazite sand and put on the market. The period of average lifeof the parent substance, mesothorium-1, is about 8 years, andduring the first two years, through the growth of radiothorium,the initial penetrating radiation is about doubled before the decaycommences. The substance then possesses the whole of the radio-activity of the thorium series in concentrated form, with theexception of a few per cent.of low range a-rays. It produces thewhole of the penetrating rays, the thorium emanation, and activedeposit, corresponding with the thorium series in the mineral fromwhich it was extracted. Although not a permanently radioactivesubstance, the useful life is sufficiently long to make it worthextracting, especially as it is merely a by-product of the thoriumindustry, which consumes annually an enormous amount of theraw material, monazite sand. Although the nature of the manu-86 G. N. Antonoff, Phi2. Mag., 1910, [vi], 19, 825 : A., ii, 568.e7 Mme. Curie and A. Debierne, Campt. rend., 1910, 150, 386 ; A., 3, 251.s8 J. W. Waters, Phil.Mag., 1910, [vi], 19, 905 ; A . , ii, 569282 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.facture of mesothorium preparations has been kept entirely secret,two separate investigations of the chemical nature of the substancehave established the interesting fact that it is absolutely identicalin all its reactions with radium.89 In the ordinary technical treat-ment of monazite sand, by heating it with excess of sulphuric acidand stirring the product with water, part of the mesothoriumremains with the insoluble residue, and part passes into solution,from which it may be removed by a bpium sulphate precipitation.If, however, a, barium compound in small quantity is added to themonazite sand before treatment, the whole of the mesothorium iscontained in the insoluble residue. From the latter, or, indeed,from any mixture containing it, it may be recovered by processesidentical in every respect to those in use in the working up ofradium residues.A long series of fractionations of bariumchloride, containing mesothorium and radium, concentrated the tworadioactive substances together from the inactive barium chloridewithout changing their relative proportions in the slightest degree.The rapidly changing product, thorium-X, is always separated withthe mesothorium and radium from minerals, and these three sub-stances form a trio of chemically non-separable radieelements.The possibility of accidental or intentional adulteration of radiumwith mesothorium must be borne in mind in view of the identityof their chemical properties and great similarity of their penetratingrays (p.269). A simple test is, after heating or dissolving thepreparation to remove radium emanation and resealing the pre-paration, to take the intensity of the penetrating rays three hoursafterwards, when the activity is due to mesothorium alone, andthree weeks later, when the full activity due to radium is alsopresent. The ratio of these two measurements gives the proportionof mesothorium present. A careful measurement of the absorptioncoefficient of the y-rays will also serve to reveal the presence ofmesothorium, the y-rays of which are rather less penetrating thanthose of radium, and this test does not require the tube to beopened. For a mixture of the two substances, instead of anexponential absorption curve with constant value of p from 1 cm.of lead onward, the value of p will decrease for the first few cm.until the value for radium is attained.90 Since thorium mineralsalways contain more or less uranium, mesothorium free fromradium has not yet been prepared.Thori?cm-D.-Electrolysis for a few seconds of the solution of theactive deposit of thorium in concentrated hydrochloric acid (0.5milliamperes with platinum electrodes 0.5 x 2.1 cm., 1 cm.apart)89 W. Marckwald, Ber., 1910, 43, 3430; A . , 1911, ii, 8 ; F. Soddy, Tram.,1911, 99, i 2 .90 A. S. Russell and F. Soddy, Phil. Mag., 1911, [vi], 21, 130RADIOACTIVITY. 283separates pure thorium-B on the cathode, the a-rays of which decaynormally with the sixty minutes half-period, but the &rays ofwhich rise from zero to a maximum with the 3-05 minutes half-period of thorium-D.Nickel shaken in the solution withdraws purethorium-B as in the electrolysis. I n these respects, thorium-D isan exception to von Lerch’s rule, that in a disintegration seriesthe successive products are progressively more “ noble ” in theirelectrochemical behaviour, thorium-D being less (‘ noble ” thanthorium-B. Thorium-D is also more easily volatilised than theother products of the active deposit, being completely removedfrom a wire by thirty seconds’ heating in a Bunsen flame, and itis also less soluble in acids.91Radioactivity of Rocks and Minerals.The rocks from the transandine tunnel proved t o be low inradioactive constituents, both thorium and radium, in agreementwith the absence of abnormal temperature gradients encounteredduring the piercing of the tunnel.g2 Calcareous and dolomiticrocks of various origins proved to be very poor in thorium.It isprobable that the element is selectively rejected by the organismsin sea water which abstract lime. But sedimentary rocks almostalways contain an easily detected quantity of thorium, 1.3 and0.6 ( x 10-5 gram of thorium per gram) being average values for theargillaceous and arenaceous group respectively. It is probablethat in these rocks the thorium has been concentrated owing tothe removal by gravity before deposition of the larger particles offelspar and q ~ a r t z . ~ 3 Ten rocks from the west coast of Sumatracontained amounts of radium of the order of 10-l2 gram per gram,which were very similar to the amounts found for rocks fromEurope and America.94A new Australian mineral, named pilbarite, after the localitywhere it is found, occurs in nodules, up to 30 grams in weight, ofamorphous, colloidal, gelatinous or gummy texture, the interiorbright canary colour being disguised by a superficial brown orred coating. It is a hydrated silicate of thorium, uranium, andlead, probably being a hydrous pseudomorph of an anhydrousparent mineral, and is soluble in strong acids, leaving silica.Analysis: U0,=27*09; Th02=31.4; PbO=17*26; Sio2=12’72;91 F.von Lerch and E. von Wartberg, Sitxungsber. K. Akad. Wiss. Wien, 1909,118, [iiu], 1575.92 A.L. Fletcher, PhiZ. Mug., 1910, [vi], 20, 36 ; A . , ii, 677.93 J. Joly, ibid., 125, 353 ; A., ij, 523, 969.94 E. H. Buchner, Proc. R. Akad. Wetensch. dmsterdum, 1910, 13, 359 ; A.,ii, 1025284 ANIL'UAL REPORTS ON THE PROGRESS OF CHEMISTRY.H,O=7.56 per cent.95the interior of Sout'h Australia is also reported in the Press.A find of another radioactive mineral inA tmospheric and Natural Radioactivity.The examination of spas and thermal springs, and waters ingeneral in all parts of the world proceeds apace on account of thesupposed medicinal value of the dissolved radium emanation, butno essentially new facts have transpired. A very completeexamination of the radioactivity of the hot springs of Iceland 96failed to throw any definite light on the nature of hot springs orto establish any direct connexion between the radioactivity andthe heat energy.The springs contained on the whole about thesame amounts of radium emanation as the mineral springs ofGermany and Austria, although none were found quite so activeas the most active of these. The absence of any appreciableamounts of radium in the sediments and deposits around thesprings is considered a strong argument in favour of the theorythat the spring water is heated by steam, as otherwise it is to beexpected that these deposits would contain radium derived fromthe rocks of the interior.Numerous investigations have also been made of atmosphericradi~activity.~~ Specially interesting are the tests made at theSestola Observatory in the Apennines, over 3000 feet high, andexposed to all the four winds.The proportion of the activity,obtained by four hours' exposure of a charged wire, due to thoriumvaried from 29 to 73 per cent., being increased by falling barometerand high ~ i n d s . ~ 8 The average amount of radium emanation inthe air at Cambridge, England, was found to be 1.7 molecules perc.c., and varied over a range of three times great'er and three timesless than this figure, according, chiefly, as to whether the prevailingwind had passed over the land or ocean previously. The ionsproduced by the average amount of emanation are 2.1 per C.C. persecond. It is estimated that in the free air the thorium emanationproduced a similar number, whilst only 1 is produced by thepenetrating rays irom the earth.I n closed vessels the latternumber may be increased fourfold.9995 Arutralian Miniizg Standard, 7/9/10.96 T. Thorkelsson, ilfe'moires de I'Acad. Royale des Sciences et des Lettres de'J7 K. Xiurz, Abh. K. Akad. Wis. Munchen, 1909, 25, 5 ; A . , ii, 476 ; A. S. EveDaneiim-k, CopedLague, 1910, [vii], 8, 182 ; A., 1911, ii, 9.Phil. Mag., 1910, [vi], 19, 657; A,, ii, 479.D. Pacini, Physikal. Zeitsch., 1910, 11, 227 ; A., ii, 374.99 J. Satterley, Phil. Mag., 1910, [vi], 20, 1 ; A . , ii, 676RADIOACTIVITY. 285Cherrhicul B elutions7~ips of t 7 ~ e Badio-elements.A method of determining the chemical nature of a member ofa, disintegration series by isomorphism consists in adding varyingsalts to the solution, allowing them partly to crystallise out, anddetermining which $inds of salts crystallise with the active material.Thus, when barium nitrate or chloride or lead nitrate crystallisesin a thorium-X solution, the crystals are very active, whereascrystals of potassium, bismuth, or lanthanum ammonium nitrateso formed are inactive. In this way, it has been found thatthorium-X, actinium-X, and radium show a complete identity ofchemical behaviour, and are members of the alkaline-earth groupof elements.' To this group,' as already described, mesothorium-1also belongs, whilst another chemically identical group comprisesthorium, radiothorium, radioactinium, ionium, and uranium-X.The three emanations form a similar group, and, working back-ward from them through the three disintegration series, thepreceding members, radium, thorium-X, and actinium-X, areidentical chemically and belong to the alkaline-earth family, whilstbefore these come ionium, radiothorium, and radioactinium, chemi-cally identical with one another and with thorium. Theseregularities2 may prove to be the beginning of some embracinggeneralisation, which will throw light, not only on radioactiveprocesses, but on the elements in general and the Periodic Law.Of course, the evidence of chemical identity is not of equal weightfor all the preceding cases, but the complete identity of ionium,thorium, and radiothorium, of radium and mesothorium-1, and oflead and radium-D, may be considered thoroughly well established.Indeed, when it is considered what a powerful means radioactivemethods of measurement afford for detecting the least change inthe concentration of a pair of active substances, and the complete-ness and persistence of some of the attempts a t separation whichhave been made, the conclusion is scarcely to be resisted that wehave in these examples no mere chemical analogues, but chemicalidentities. The atomic weight of the members in these groupscannot be the same. For example, that of ionium must be 230.5,of thorium 232.5, and of radiothorium 228-5. Radium-D mustbe four units higher than lead; whilst radium, 226.5, mewthorium-1, 228.5, and thorium-X, 224.5, are like the first group,two units separating the consecutive members. On the other hand,I). Stromholm and T. Svedberg, Zeitsch. nnorg. Chem., 1909, 61, 338 ; 63,Compare also 0. Hahn aid L. Meitner, Phylsikal. Zeitsch., 1910, 11, 493 ; A,197 ; A., 1909, ii, 200, 849.ii, 566286 ANNTJAL REPORTS ON THE PROGRESS OF CHEMISTRY.some members which presumably have identical atomic weightbelong to different families, as mesothorium-1 and radiothorium,radium-D and polonium. . The recognition that elements of differentatomic weight may possess identical chemical propertis seemsdestined to have its most important application in the region offnactive elements, where the absence of a second radioactive nature,totally unconnected with the chemical nature, makes it impossiblefor chemical identities to be individually detected. Chemicalhomogeneity is no longer a guarantee that any supposed elementis not a mixture of several of different atomic weights, or thatany atomic weight is not merely a mean number. The constancyof atomic weight, whatever the source of the material, is not acomplete proof of homogeneity, for, as in the radio-elements, geneticrelationships might, have resulted in an initial constancy of pro-portion between the several individuals, which no subsequentnatural or artificial chemical process would be able to disturb.If this is the case, the absence of simple numerical relationshipsbetween the atomic weights becomes a matter of course rather thanone for surprise.FREDERICK SODDY

ISSN:0365-6217    

DOI:10.1039/AR9100700256

出版商:RSC    

年代:1910

数据来源: RSC

摘要:

INDEX OF AUTHORS’ NAMES.Abderhalden, E., 146, 147, 183, 188,Ackermann, A., 95.Ackermann, D., 148.Ackroyd, H., 189.Acree, S. F., 61.Alvarez. See PifierGa Alvarez.Amadori, M., 4.Amann, J., 30.Anderson, J. F., 201, 203.Andresen, H. B., 182.Angel, F., 236.Angeli, A., 98.Angelico, F., 138.Annett, H. E., 213.Antonoff, G. N., 281.Antropoff, A. von, 21, 161.Armstrong, E. F., 183, 214.Armstrong, H. E., 82, 214, 233.Arnold, H., 171.Arnold, W., 182.Arsandaux, H., 247.Asahina, Y., 144.Aschan, O., 92, 117, 118.Ashdown, Miss 0. E., 149.Aufrecht, 182.Auer, J., 202.Autenrieth, W., 151.Auwers, K., 67, 69.Auzinger, A., 174.Azdma, 246.Bach, A., 149.Backe, A., 175.Baeyer, A. von, 116.Baeyer, 0. von, 265.Bain, Miss A. M. 93.Baker, H.B., 33,’ 39, 50.Baker, J. L., 174.Balke, C. W., 27.Ball, W. C., 168.Baly, E. C. C., 81.Bamberger, E., 66.Bamford, Miss H., 109.206, 222.REP.-VOL. VII.Bang, I., 188, 189.Barbier, P., 236, 241, 244, 253.Barcroft, J., 192, 194.Rardach, B., 185.Bardt, A., 254.Barger, G., 138, 139.Barkla, C. G., 270.Barlow, W.: 229.Barnebey, 0. L., 169.Barnett, E. de B., 153, 154, 155.Barringer, D. M., 255.Baume, G., 6.Beard, S. H., 75.Beatty, R. T., 270.Beckmann, E., 5.Beger, M., 55.Bemmelen, J. M. van, 247.Benedict, F. G., 182.Benner, R. C., 170, 171.Benz, M., 144.Berger, C., 222.Bergmann, M., 72.15x1, E., 157, 158, 184.Bernoulli, W., 98.Berry, A. J., 21, 274.Rertrand, G., 174.13e;sson, A., 54.Eeuttel, F., 151.Beys, C., 178.Bider-Chatelan, 180, 212.Bierling, E., 176.Bierry, H., 106.Biilmann, E., 90, 91.Billeter, O., 153.Biltz, H., 49, 165.Bjerrum, N., 90.Blaise, .E.E., 109.Blake, G. S., 242.Blanquies, Mlle. L., 277.Blasdale, W. C., 171.Blass, C., 233.Bleyer, B., 41.Blichfield, S. H., 177.Blockey, J. R., 64.290 INDEX OF AUTHORS’ NAMES.Blumenthal, F., 200.Boddener, I<. H., 108.13ohi, A., 23.Boehner, R., 146.Boeseken, J., 175.Bogojawlensky, A. D., 8.Bolin, I., 149.Boll, P., 136.Boltwood, B., 262.Rone, W. A., 33, 50, 102.Rsongrand, J. C., 104.Bonis, 178.Bonnerot, S., 42.Bordas, F., 185.Bornemann, F., 169.Borodowsky, M7. A., 267.Borsche, W., 69.Bose, E., 9.Bouga,ult, J., 141.Rouefield, W.R., 4.Bouveault, L., 158.Bowman, H. L., 254.Boyd, R., 98.Boyle, R. W., 280.Bradley, W. M., 244.Brady 0. L., 153.Bragg: W. H., 268, 270.Braun, J. von: 152.Rraunstein, A., 205.Bray, W. C., 163.Brenchley, W. E., 218.Brigl, P., 189.Briner, E., 52.Brioux, C . , 220.Rrodie, T. G., 193.Brown, A. J., 215.Brown, J. N., 258.Browning, C. H., 197.Browning, P. E., 169.13rune1, R. F., 61.Bruni, G., 4.Bube, K., 164.Buckmaster, J. H., 171.Biichner, E. H., 285.Burgess, M. J., 103.Rurmann, jun., J., 176.Burnley, M. C., 71.Rurschanadze, T., 103.Burt, F. P., 21.Busch, M., 79, 96, 99.Cahen, E., 165, 167, 220.Calvi, G., 161.Cambi, L., 52.Camboulives, P., 55.Cameron, F. hi., 209.Campbell, A. F., 90, 112.Canfield, F.A., 237.Carles, P., 178.Carpiaux, E., 180.Caw, F. H., 82, 176.Carvallo, J., 22.Caspari, W., 192.Caspari, W. A4., 245.Cavazza, L. E., 180.Centnerszwer, M., 160.Cermack, P., 273.CesBro, G., 248, 253.Challenger, F., 84.Chamot, E. M., 181.Chapman, A. C., 184.Chapman, D. L., 45, 55.Chapman, J. C., 270.Chardet, G., 180.Charitschkofl, K. ?V., 70, 162.Charpy, G., 42.Chick, Miss F., 72.Chittock, C., 24.Christiaens, A., 189.Ciacci, E., 184.Ciusa, R., 135.Clark, E. D., 183.Clarke, H. E., 254.Clarke, H. T., 72.Claude, G., 56.Clammann, P., 55.Clayton, A., 76.ClBment, L., 179.Clough, G. W., 85, 86.Cohen, E., 53.Cohen, J. B., 64. 84, 87.Cohnheim, O., 194.Colgate, R. T., 82, 233.C,ollie, J. N., 56.Ctolman, H.G., 164.Colomba, L., 243, 245.Copaux, H., 235.Cone, L. H., 112, 114.Coppola, A., 125.Copthorne, H. N., 178.Couzens, E. G., 129.Cowap, &I. D., 51.C,oward, H. F., 50, 102.Cramer, W., 206.Crawford, *4. C., 224.Crook, T., 242.Crookes, Sir W., 50.Crossley, A. W., 122.Crowther, J. A., 266.Cruess, W., 171.Crymble, C. R., 82.Cumming, A. C., 35, 36.Curie, Mme. M., 40, 256, 262, 277,Cusmano, G., 111, 132.Cuthbertson, C., 20, 21.Cuthbertson, M., 20.Dahm, K., 194.Dakin, H. Q., 65: 189.D’Ans, J., 55.Darzens, G., 97, 100.281INDEX OF AUTHORS’ NAMES. 291Davenport, A. T., 163.Dawson, H. M., 64.Deakin, Miss S., 72.Debierne, -A., 40, 262, 277, 278, 281.Deerr, N., 174.Deiss, E., 167.DelBpine, M., 152.Delpy, M., 184.DenigBs, G., 172, 178.Denison, R.B., 23.Dennstedt, M., 173.Densch, 180.Desch, C. H., 80.Desvignes, 176.Dewar, Sir J., 14, 16, 51, 52, 104, 262.Diefenthaler, O., 166.Dimroth, O., 125, 126, 128, 132.Dittler, E., 226.Dixon, H. B., 31.Dixon, W. E., 198.Dmochowski, R., 180.Doelter, C., 228.Doring, T., 168.Doerr, 204.Doscher, H., 173.Donath, E., 167.Donau, J., 158.Donnan, F. G., 44, 65.Dorn, E., 9, 10, 11, 12.Doroschewsky, A. G., 254.Douglas, C. G., 191.Dover, Miss M. V., 171.Duane, W., 256, 271, 279.DuchbEek, F. 174.Dudley, H. +., 87.Dumitrescu, G., 177.Dunoyer, L., 267.Duparc, L., 241, 242, 245.l h t o i t , P., 159.Dyer, B., 171.Easley, C W., 27.Eberhard, G., 253.Ebler, E., 41, 277.Ehrenberg, P., 218.Ehrenhaft, F., 267.Eisenkolbe, P., 222.Eisenlohr, F., 67, 69.Eisenschiml, O., 178.Elger, F., 66.Elliott, A.H., 160.Elvove, E., 176.Emich, F., 158.Engler, C., 102, 103.Epstein, F., 33.Erdmann, E., 160, 264.Erlenmeyer, E., 90.Escher, R. von, 74.Euler, H., 149.Evans, E. J., 272.Evans, W. W., 50.Eve, A. S., 284.Ewers, E., 177.Ewins, A. J., 138, 139, 176.Fajans, K., 66, 83.Falco, F., 96.Faltis, F., 136.Farcy, L., 181.Farnngton, 0. C., 255.Feist, F., 89.Fendler, G., 177.Fenton, H. J. H., 163.Fester, G., 125.Fichter, F., 98.Fiedler, A., 148.Field, S., 43.Fildes, 200.Finch, G., 158.Fischer, E., 74, 85, 109, 146, 147, 148.Fischer, F., 53, 56,Fischer, H., 109.Fischer, W. M., 167.Flawitzky, F.M., 227Flebbe, R., 222.Fleck, A., 88.Fleischmann, M., 99.Fletcher, A. L., 260,. 283.Fleury, P., 179.Flint, W. It., 28.Florence, D. C. H., 270.Fldrscheim, B., 63.Foa, I., 155.Focke, C., 176.Foerster, F., 170.Foizik, A., 28.Fonzes-Diacon, H., 178.E’oote, H. W., 169.Forbes, A, 161.Ford, W. E., 239,. 240, 242, 244.Poresti, G., 177.Forster, A., 152.Porster, M. O., 94, 124, 125, 126, 133.Fosse, R., 115.Foucar, J . L., 165.Fournier, H., 101.Fournier, L., 54.Fox, J. J., 81.Fraatz, 238.Frabot, C., 181.Frankel, S., 188.Francis, A. G.,.27.Frank, M., 233.Franke, A., 110.Freund, M., 137.Friederich, W., 55.Fritzsche, H., 145.Fromm, E., 152.Fromme, J., 167, 239, 251, 253.Fuchs, K., 146.Funk, C., 146, 188.u 292 Ih’DEX OF AUTHOI~S’ NAMES.Gadamer, J., 136.Galkin, X., 239, 250.Galliot, 39.Gambarjan, S., 150.Grams, A., 136.Garland, C.S., 133.Garrett, C. S., 108.Gatz, E., 197.Gautier, A:, 52.Gay, 203.Geiger, H., 257, 258, 259.Gcis, T., 148.Gemmell, A., 168.Giesel, F., 13.Gilling, C., 1B.Giolitti, F., 42.Gisiger, E., 98.Glascock, B. L.. 40.Glasson, J. L., 270.Glimm, E., 183.Godden, W., 131.Gorgey, R., 248, 252, 253.Gorner, P., 185.Goldbaum, J. S., 172.Goldschmidt, V. &I., 90.Gomberg, hl., 112, 114.Gomolka, F., 53.Gonnard, F., 241, 244. 253.Gooch, F. A., 163, 171.Gortner, C. V., 96.Gortner, R. A., 96, 149.Goujon, 178.Gowing-Scopes, L., 159.Grafe, E., 173.Graham, R. P. D., 243.Grandjean.F., 254.Gray, J. A., 265.Gray, R. W., 278.Graziani, F., 66.Greaves, J. E., 181.Greenlee, A. D., 175.GrBaoire, A., 180.Griffiths, E., 250.Griqnard, V., 99.Grimmer, W., 180.Groh, R., 85.Grossmann, H.. 89, 164, 165, 166.Griinhut, L., 160.Guertler, W., 254.Giittisch, A,, 166.Guggenheim, M., 147.Guignard, L., 214, 215.Guntz, A., 39.Guthzeit, M., 110.Gutmann, L., 159.Guye, P. A., 4, 6.Gwiggner, A., 161.Haar, A. W. van der, 149.Haber, F., 33.Hahnel, O., 56.Haemmerle, V., 226.Hahn, A., 158.Hahn, O., 265, 285.Haldane, J. S., 191.Halliburton, W. D., 198.Halmai, B., 102.Hankam. O . , 110.Hantzsch, A., 68, 73, 76, 77, 78, 79,H a n d , J., 165.Harcourt, A. G. V., 165.Harkins, W. D., 164.Harries, C.D., 70, 116, 118, 119, 147.Harrison, W., 173.Hartmann, E., 110.Hartmann, W.. 160.Hassler, F., 173.Hauke, M., 227.Hauser, O., 238, 240, 243, 250.Hegland, J. M. A., 177.Heidelberger, M., 168.Heilbron. J., 77.Heller, G., 129.Hempel, W., 159.Henderson, G. G., 98, 117, 123.Henderson, L. J., 161.Henri, V., 106.Henrich, F.. 160.Henriques, V., 181.Heritage, G. I,., 71.Herschfinkel. H., 280.Hertz, H.. 51.Herzenstein, A., 73.Heslop, M. K., 244.Hewett, D. F., 249.Hewitt. J. T., 130,’149.He-ydrick. K., 233.Heydweiller, A . . 22.Hicks, W. T,., 95.Hiwins, H. L., 173, 182.Hilditch, T. P., 86.Hilgendorff, G., 90.Hillebrand, W. F., 237, 246.Hilpert,, S., 227.Himmelbauer. A.. 251.Hinrichsen. F. W., 119.Hinsberg, 0..151, 152.Hintz, E., 160.Hirokawa, W.. 189.Hladik. J.. 158.Hocheder, F.. 217.Hock, H.. 128.Hodtke, O . , 165.Holter, L., 164, 165.Hofmann, K. A., 75, 115, 128.Holde, D.. 178.Holmes, Miss M. E., 171.Homer, Miss A.. 82.Homfray, Miss I. F., 9.Honcamp, F., B3.Hopwood, A., 148.114IKDEX OF AUTHORS’ NAMES. 293Horrniann, P., 138.Hough, G. J., 167.Howard, H., 164.Howell, W. H., 189.Hubert, A., 178.ILudson, C. S., 23, 87, 173Hughes, W. E., 170.Hultou, H. F. E., 174.Humphreys, T. C., 170.Humphries, H. B., 85.Huntley, G. N., 161.Hixth, M. E., 12.Huttner, F., 56.Inaba, R., 197.Irvine, J. C., 108.Isham, R. M., 169.Jackson, F. G., 16.JaffB, G., 21.Jager, L. de, 182.Jamieson, G. S., 167.Jannasch, P., 164.Jerusalem, G., 234.Jorgensen, G., 185.Johnson, Miss A., 173.Jolibois, P., 53.Jolles, A., 174.Joly, J ., 260, 283.Jones, G. C., 183.Jones, H. C., 43.Jones, H. E., 55.Jones, H. O., 51, 52, 91, 104, 150.Jones, W., 188.Jurrissen, A. W., 157.Kalmus, 185.Karandkeff, B., 227.Kasarnowski, H., 158.Kasztan, M., 187.Knto, Y., 22.Keetman, B., 275.Kehrmann, F., 114.Kellner, O., 222.Kendall, E. C., 183.Kepinoff, L., 205.Kiefer, A., 98.Killhy, L. G., 48.Kimley, W. S., 170.Kindscher, E., 119.Ring, W. 0. It., 192.Kipping. F. S., 84.Kirby, 0. F., 163.Kirkby, P. J., 32.Kirmreuter, H., 75, 115.Kleeman, R. D., 267, 270.Klein, F., 176.Kleine, A., 158.Klemperer, R,. von, 159.Klever, H. W., 73.mxg, E., 217.Knorr, A., 74.Knorre, G.von, 164.Kober, P., 73.Kober, P. A., 158.Koch, A., 213, 214.Kogel, W., 79.Koehler, A., 109.Kohler, F., 148.Koenig, P., 218.Kohler, E. P., 171.Kohn-Abrest, E., 49.Kollock, Miss L. G., 171.Kolowrat, L., 279, 280.Koninck, L. L. de, 161.Kooper, W. D., 219.Koref, F., 14.Kovarik, A. F., 267.Kramers, G. H., 137.Krapiwin, S., 97.Krassa, P., 33.Kratter, J., 185.Kreikenbaum, A. , 178.Kreis, H., 175.Kretschmer, A., 243.Krogh, A., 190, 191Krogh, Mme. M., 190.Kdster, W., 145, 146.Kuntzen, H., 92.Kurbatoff, W. A., 15.Kurz, K., 284.Lahorde, A., 256, 279.Lachmann, S., 106.Lacrolx, A., 237, 241, 242, 245, 249.Lacy, B. S., 33.Ladenburg, A., 83.Lambert, B., 38.Landau, B., 89.Langer, J., 174.Langley, J.N., 187.Langley, R. W., 169.Lapworth, A., 72, 83.Lasserre, A., 179.Lauritzen, M., 182.Lecco, 1cI. T., 181, 184.Leeden, R. van der, 247.Lehmann, F., 165.Lehmann, O., 6, 7, 9, 12.Lehmann, R., 240.Leitmeier, H., 248, 249.Lemeland, P., 174.Lerch, F., von., 283.Leuchs, H., 136.Lewis, G. N., 23.Lewis, W. J., 238.Leyko, Z., 143.Liddle, L. M., 222.Liebermann, C., 90.Lindemann, F. A., 14, 17.Lindstrom, G., 248.251294 INDEXLing, A. R., 182, 183.Lippmann, E., 150.Little, H. F. V., 165, 167.Lloyd, S. J., 273, 275, 279.Lochte, 185.Lockemann, G., 185.Lob, W., 106.Loffler, K., 97.Lotsch, E., 180.Lcewy, A., 192.Lohmann, W., 10.London, E. S., 188.Lorenz, R., 23.Louderback, G. D., 237.Louise, E., 179.Lovisato, D., 238.h w r y , T.M., 4, 80.Ludwig, E., 183, 254.Luff, B. D. W., 138Lumpp, H., 162.Luniak, A., 147.Lutz, O., 86.Lyman, J. F., 189.McCay, L. \V., 165.McCrackan, R. F., 167.McIntosh, 200.Mackay, G. M., 163.McKenzie, A., 85, 86.McLintock, W. F. P., 242.MacMahon, P. S., 45.Mchlillan, A., 137.McWeeney, J., 185.Maderna, G., 162.Magnus, A., 14, 17.Magnus, R., 187.Mailhe, A., 96, 99, 100.Makower, W., 272.Malarski, H., 143.Malfatti, H., 182.Manasse, E., 246, 251.Manchot, W., 56, 129, 192.Mannich, C., 139.Marchlewski, L., 143.Marcille, R., 178.Marckwald, W., 28,. 275, 282.Marcusson, J., 173, 177, 178.Mares’, F., 188, 189.Margaillan, L., 174.Marsden, E., 257, 259, 271.Marsden, Rl[i,ss E.G., 81.Marsh, J. E., 35.Marshall, E. K., 61.Marshall, J., 84.Masing, E., 188.Massini P., 54.Mason,’ J. I. O., 36.Matsui, M., 97.Mecklenburg, W., 166, 177.Medigreceanu, F., 206.Meillkre, G., 179,OF AUTHORS’ NAMES.Meisenburg, K., 68.Meitner, L., 265, 285.Melcher, A. C., 34.Meldola; R., 92, 97, 130.Mellet, R., 161.Mendel, L. B.. 188. 189.Mennell, F. P., 244, 250.Merrill, G. P., 255.Merzbacher, S., 126, 145.Rletcalfe, E. P., 20.Rfetzger, F. J., 167, 168.Meyer, E., 271.Meyer, K. H., 73, 74.Meyer, R. J., 168, 253.Meyerfeld, J., 162.Michael, A., 54, 61.Rlicko, K., 175.Mieth, H., 213.Miller, W. von, 91.Milobendski, T., 162.Millosevich, F., 236.Mills,. W. H., 93.Mingaye, J. C. H., 168, 169.Mirande, M., 214.Mita, 185.Mitchell, H., 276.Mitscherlich, E.A., 211.Modrakowski, 188.Mohr, E., 148.Moir, J., 184.Mojoiu, P., 159.Mond, L., 51.Montagne, P. J., 63.Mooy, W. J. de, 6.Morgan, G. T., 129, 130, 131,Morgen, A., 222.Morrell, R. S., 179.Moses, A. J., 251.Mossler, G., 136.hlott, F. W., 198.Moureu, C., 104.Miiller, E., 166.Muller, I?., 188.hliiller, H., 228.Muller, O., ’194.Miiller, R. 124, 126.Murat, M., 96.Murmann, E., 167.Murphy, A., jun., 55.Muttelet, F., 174.Mylius, F., 169.Nacken, R., 227.Nametkin, S. S., 96.Naumann, A., 34.Nef, J. U., 107.Nernst, W., 14, 15, 18.Nest, J. S. van, 234.Neuberg, C., 106.Neumann, E., 41.Neumann, R., 222INDEX OF AUTHORS’ NAMES. 295Newman, S. H., 124.Nicolardot, P., 179.Niemann, A., 188.Nirdlinger, S., 61.Novak, J., 47.Noyes, A.A., 22, 24, 161.Oddo, B., 99.Ogilvie, J. P., 174.Olie, J., jun., 53.Olivari, F., 5.Oliveri-Mandalh, E., 125.Orbeli, 192.Osborne, T. B., 222.Ostromisslensky, I. von, 103.Ostwald, Wo, 3.Oswald, 251.Otto, R., 219.Paal, C., 160.Pacini, D., 284.Padoa, M., 66.Page, H. J., 154.Palache, C., 239, 240, 242, 244, 245,248, 250, 252, 253.Palazzo, F. C., 125.Palitzsch, S., 161.Palladin, A, 183.Palm&, J., 116.Palmer, H. E., 166, 169.Pape, K., 176.Parker, J. G., 180.Parsons, C. L., 50.Pascal, P., 69.Pasztor, B., 171.Patterson, T. S., 88.Paul, M., 180.Pawloff, P. N., 13.Pellet, H., 175.Pennington, Miss M. E., 175.Perkin, F.M., 170.Perkin, W. H., jun., 121, 122, 123,135, 136, 138.Perkins, C. C., 163.Perrot, F. L., 6.Petersen, I., 147.Petersen, J., 162.Peterson, P. P., 95.Petroff, S., 163.Pfenning, F., 166.Pfister, K., 132.Phelps, J., 169.Phillips, A. H.. 236.Piccard, J., 163.Pickard, J. A., 130.Pickering, S. U., 212.Pickles, S. S.. 119.Pictet, ’ 14., 136, 137.Pier, M., 19.PiliDenko. P. P.. 240.Pildty, O:, 142, 144, 145.Piiieriia Alvarez, E., 162.Piper, S. H., 270.Pirret, Miss R., 276.Piutti, A., 263.Plato, W., 165.Pletneff, D., 194.Plochl, J., 91.Pollock, E. F., 117.Pomine, G., 89.Poole, H. H., 271.Pope, W. J., 83, 229.Popescu, D. M., 177.Posner, T., 71.Potts, H. E., 65.Pouget, I., 181.Pozzi-Escot, M. E., 220.Prandtl, W., 41.Pratt, D.S., 181.Pregl, F., 141.Preuss, G., 159.Price, T. S., 170.Prilescha&eff? N., 150.Primot, C., 177.Pring, J. N., 50, 102.Pringle, H., 207.Prior, G. T., 249, 252, 255.Pschorr, R., 137.Pucciante, L., 8.Pulvermacher, G., 106.Purdie, T., 85.Purvis, J. E., 82, 91, 150.Pyman, F. L., 137, 139.Quitmann, E., 142.Rahe, P., 136, 137.Raffo, M., 177.Raiziss, G., 152.Rakoczy, A., 188.Ramsay, Sir W., 278.Ranc, A., 106.Rankine, A. O . , 20.Ransome, F. L., 236, 241.Raschig, F., 53.Rassenfosse, A., 46.Read, H. I,., 171.Read, J., 83.Reckleben, H., 166.Reich, P., 136.Reichard, C., 173.Reid, E. E., 97.Reinders, W., 46.Reinhardt, F., 174.Reinhold. B., 24.Reitzenstein, F., 98, 172.Reuter, It., 89.Reverdin, F., 130.Reynolds.W. C.. 82, 137, 176.Rhead, E. T i , 166.Richards, T. W., 16, 26.Richardson, C., 245296 INDEX OF AUTBORS’ NAMES.Richet, C., 203.Riesenfeld, E. H., 24.Riiber, C., 90.Rindell, A., 34.Rinne, F., 255.Ritter, H., 101.Rivett, A. C. D., 64, 71.Robel, J., 143.Robertson. P. W.. 77.Robinson, ’R., 135; 136, 138.Robison, R.. 77.Rodd, E. H:, 82, 233.Roemer, H., 168.Rocsner, H., 148.Rossler, L., 169.Rohde, E., 193.Rohde, K., 71.Rollett, A., 137.Rosenau, M. J., 201, 203.Rosenbloom, J., 189.Rosenheim, O., 188, 206.Rosenmund, K. W., 138.Rosenthaler, L., 178, 185.Rosicky’, V., 238, 240.Rost, H., 97.Rotarski, T., 13.Roth, R., 128.Roth, W. A., 69.Rouillard, 178.Routala, 0.) 102.Rudorf, G., 21.Ruer, R., 254.Ruff, O., 169.Ruhemann, S., 76.Runne, E., 176.Rupe, H., 86.Rupp, E., 165, 166.Rusconi, A., 179.RUSS, 204.RUSS, S., 272.Russell, A.S., 269, 274, 275, 282.Russell, E. J., 212, 213.Rutherford, E., 258, 259, 261, 252.Sabatier, P., 99, 100.Sabot, R., 242.Salle. 181.Salvadori, R., 162.Salway A. H., 137.Sand. H. J. S.. 149, 170, 171.Sanders, J. M.,’ 159; .Santi, L:, 66:Sasaki, T., 173.Satterley, J., 280, 284.Sauerland, F., 188.Sawitsch, W., 188.Scaffidi, V., 188.kagliarini, G., 135.Schaefer, K., 82.Schaller, W. T., 236, 237, 239, 240,241, 242, 246, 248, 249.Scheibler, H., 85.Schenck, R., 7, 8.Scheuer, 0.) 88.Scheunert, A., 180.Schimpff, H., 17.Schittenhelm, A,, 188.Schlenk W., 73.Schmidfin, J., 54, 72, 74, 99.Schmidt, H.W., 267, 273.Schmidt, J;, 74, 162.Schmidt, M. von, 142.Schneider W., 151.Scholl, R.’, 173.Scholtz, M., 92.Schrader, H., 74.Schroder, J., 22.Schroter, F., 605.Schroeter, %., 63, 126.Schryver, S. B., 172, 216, 217.Schuck, B., 166.Schurmann, E., 171.Schuz, E., 253.Schulze, E., 147.Schweidler, E. von, 271.Scott, L., 106.Scott, W. M., 203.Seidel, T., 164.Seisser, P., 188.Semmler, F. W., 120.Senderens, J. B., 99, 100.Senter, G., 64.Serra, A,, 228.Shaw, T. W. A., 44.Shaw-Mackenzie, J. A., 206.Shedd, 0. M., 168.Sherman, H. C., 183.Sidgwick, N. V., 64, 71.Sieverts, A., 43.Silberstein, S., 185.Simonsen, J. L., 109.Simpson, E. S., 237, 243, 244, 246, 249.Skirrow, F.W., 164, 165.Skita, A., 101.Slator, A., 149.Sloan, W. H., 24, 45.Slyke, D. D. van, 181.Smalley, W. M., 171.Smedley, Miss I., 68.Smiles, S., 153, 154, 155.Smith, c., 134.Smith, E. F., 171, 172.Smith, 1,. L., 255.Smits, A., 6.Smythe, J. A., 152, 244.Sobecki, W., 83.Soddy, F., 21, 264, 269, 274, 275, 276,Soddy, Mrs. W. M., 269.Sorensen, S. P. I,!., 147, 161, 181, 182.Sommerfeldt, E., 235.Sosman, R. B., 22.282297Souczek, H., 278.Soukup, A., 165.Sourlis, A., 129.Southard, 203.Southgate, H. W., 80.Sowton, Miss S. C. M., 187.Spiith, E., 97.Spear, E. B., 171.Spencer, L. J., 239, 252.Spetcr, &I., 168.Spindler, 0. von, 181.Spoehr, H. A., 107.Stahler, A., 170.Stamm, G., 172.Stark, O., 98.Staudinger, H., 73.Steele, B.D., 161.Stepanoff, A., 114.Stendel, H. 189.Stevenson, i l k s E. F., 88.Stewart, A. W., 82.Stewart, 81. A., 24.Stewart, R., 181.Stieglitz, J., 63, 95.Stobbe, H., 75, 90.Stock, A . , 53.Stoecklin, E., de, 149.Stoermer, R., 66.Stoll6, R., 172.Stoltzenberg, H., 160.Straub, H., 194.Straub, W., 187.Straus, F., 95.Strecker, W., 99.Stromholm, D., 285.Stroschein, F., 148.Strutt, Hon. R. J., 262, 263.Stuckert, L., 160.Stumpf, F., 12, 13.Sudborough, J. J., 70, 75.Surre, I,., 178.Sutherland, Miss M. M. J., 123.Svedberg, T., 285.Sventoslavsky, W., 130.Swann, W. F. G., 17.Taggart, W. G., 175.Tammann, G . , 1.Tanatar, S., 163.Tasker, H. S., 150.‘I‘:itlock, R. €3..175.Tavanti, G., 42.Taylor, R. L., 47.Tcbb, Miss 31. C., 188.Thal, A., 115.Thierfelder, 13.. 188.Thoday, D., 217.Thole, F. B., 130.Thomas, F. E., 33.Thomas, J., 70.Thommen, H., 74.Thompson, R. T., 175.Thomson, D., 111.Thomson, J. C., 38.Thomson, Sir J. J., 266.Thorkelsson, T., 284.Thorpe, J. F., 89, 90, 112.I’horpe, Sir T. E., 27.Thunberg, T., 194.Tiffeneau, 11.. 97.Tilden, Sir W. A., 118.Tizard, H. T., 161.Tollens, B., 108, 180.Tolman, R. C., 23.Tower, 0. F., 167.Traube, W., 149.Trier, G., 147.Trucksiiss, H., 90.Triimpler, A., 152.Tsakalotos, I). E., 6.Tschermnk, G., 228. 254.Tschernik, (3. P., 242.Tsvett, JI., 144.Tuck, W. B., 81.Tutton, A. E. H., 234.Uhlenhuth, R . , 163.Uhlig, E. C., 161.Uhlig, J., 247, 250.ITlpiani, C., 220.Underhill.F. P., 188.Urazoff, G. G., 42.Ilrbasch, S., 159.Usher, F. L., 52.Vassallo, E., 161.Vaubel, W., 178.Vaiighan, 203.Vavon, G., 117.Veley, V. H., 187.Venturoli, G . , 184.Verneuil, A . , 50, 251.Vernon, R. H., 158.Vesterberg, A . , 181.VQzes, RI., 180.Viehover,, A,, 176.Vinson, A. E., 216.Vogtlin, C., 188Voishet, E., 178.Vorliinder, I)., 6, 7, 8, 9, 13.Voss, A., 136.Vournasos, A. C., 44, 184.Waentig, P., 5, 29.Wagner, H., 74.Walden, P., 5.Walker, P. H., 179.Wallach, 0.. 97, 110, 120, 123.Waller. A. D., 184, 187, 216.Wallerant, F., 9.Walpole, G. S., 139, 182.Walter, E., 185298 INDEX OF AUWartberg, E. von, 283.Waser, E., 101.Washburn, E. W., 23.Washington, H. S., 235, 236.Waters, J. W., 281.Watson, 8. E., 30.Watts, Miss C. H., 134.Wechsler, E., 72, 83.Wedekind, E., 93, 240.Wedekind, O., 93.Wegscheider, R., 97.Werckel, T.,- 73. .Weil, H., 173.Weimarn. P. P. von, 3, 13. I , Weiss, L., 41, 240.Weizmann, C., 148.Wells, E. E., 171.Wells, H. G., 188.Wells, R. C., 246.Welsbach, C. A. von, 276.Wenz, W., 45.Werner, 238.Werschinin, N., 187.Wertenstein, L., 273.Westhausser, F., 222.Weyl, T., 182, 223.Wheeler, 203.Wheeler, R. V., 103.Wheldale, Miss M., 219.Whit,by, G. S., 165, 250.Wiechowski, W., 188.Wielen, P. van der, 176.Wilkie, J . M., 221.Willcs, W. A. R., 49.HOES' NAMES.Willard, H. H., 26.Williams, 0. T., 189.Willstatter, R., 101,. 144, 145,Wilsmore, N. T. M., 72.Wilson, W., 265, 266, 267.Winogradoff, N., 8.Winter, H., 253.Winterfeld, G., 177.Wirth, F., 240, 243.Witte, 174.Wohl, A., 183.Wohl, J.. 74. 99.Wohfgekuth; J., 183.Wolff, J., 149.Wolters. A.. 228.wood, T. k, 221.Woodmansey, A., 64.Wren, H., 85.Wright, F. E., 235, 236, 246.Wright, R., 82.Wroczynski, A., 6, 52.Wunder, M., 242.Wulff, G., 13.Yoder, P. A., 175.Zaar, B., 120.Zambonini, F., 233, 249.Zeidler, F., 137.Zeller, T., 180.Zemplhn, G., 109, 147.ZimBnyi, K., 252.Zimmerli, A., 94.Zorn, L., 99.217

ISSN:0365-6217    

DOI:10.1039/AR9100700289

出版商:RSC    

年代:1910

数据来源: RSC

摘要:

INDEX OF SUBJECTS.Acetic acid, trichloro-, detection of, 172.Acetone, condensation of fructose and,Acetonitrile, nitro-, 105.Acids, fatty, halogenated, action ofActinium, 276.Actinium-B, 277.Adamite, 238.Alcohols, molecular weights of, 5.Aldehydes, detection of, 172.Alexandrite, 238.Alkali-metals, emission of electronsfrom, 267.Alkaloids, 135.analysis of, 175, 185.Alkylation, 97.Alloys, preparation of, 39.electro-deposited, formation of, 43.Alstonite, 238.Aluminium silicide, 49.Alums, diffusion of, 50.Smalgams. See Mercury alloys.Amines, preparations of, 97.dmino-compounds, analysis of, 181.Ammonia, action of radium emanation107.silver nitrate on, 64.on, 52.heat of formation of, 18.Amphibole group, 239.Analysis, physical, 159.Anaphylaxis, 201.Anemousite, 235.Anhydrides, velocity of hydration of,Antlerite, 239.Apophyllite, 239.Apparatus, analytical, 157.Argon, preparation of, 56.Arsenic acid, detection of, 162.Arsenopyrite, 239.Asymmetry, 83.Atacamite, 239.Atomic heats, 16, 17.weights, 26.64.Axinite, 239.Axoxy-compounds, preparation of, 98.Azo-compounds, 123.Baddeleyite, 240.Barbierite, 235.Barium sulphate, solubility of, 34.Barytocelestine, 240.Bementite, 240.Benzenepolycarboxylic acids, constitu-tion of, 109.Bertrandite, 240.Beryl, 240.Bile, acids of, 139.Bismite, 241.Bismuth, estimation of, 165.Bityite, 241.Bleaching powder, chemical behaviourof, 47.Blood, analytical reactions of, 185.Bornylene, 116.Boron, “ crystalline,” 49.Brochantite, 242.Broggerite, 242.Bromination, 98.Caesium, estimation of, 168.Calcium, estimation of, 159.carbide, action of, on hydratedcarbonate, solubility of, 34,hydroxide, action of bromine on, 48,sulphate, solubility of, 34.crystals, 36.49.Calorimeters.14, 15.Camphene, 116.Cancer, chemistry of, 204.Caoutchouc, 118.Carbohydrates, 105.Carbon monoxide, effect of pressureon, 52.monosulphide, 51, 104.subnitride, 104.Carbonium compounds, 112300 INDEX OF SUBJECTS.Carbon-ring, formation of the, 109.stabilitv of the. 110.Carbonyli, metalfic, 51.Carnegieite, 235.Carnohe, 242.Caro’s acid, new synthesis of, 55.Catalysis, 64, 65.Cerium, estimation of, 168.Cheirolin, 151.Chlorine, atomic weight of, 26.Chlorophyll, 142.Cinnamic acids, isomeric, 90.Coal, volatile constituents of, 103.Cobalt, detection of, 163.Cobalt ocalcit e, 236.Colour and constitution, 74.Combustion, 30, 33.Compounds, specific heats of, 14.Conductivity, 24.Constitution and colour, 74.and optical activit 86.Copper, detection o[’ 163.estimation of, 171.Cordierite, 242.Cork, 141.Crgoscopy, 5.Crystallography, 229.Crystals, hydrated, action of calciumcarbide on, 36.liquid, 6 e t seq.“Cupferron,” use of, in analysis, 165.Cupric salts, colour of, 46.Cuspidine, 242.Cyanides, analysis of, 164, 184.Dahllite, 242.Datalite, 242.Dawsonite, 243.Diazo-compounds, 128.Drugs, analysis of, 175.Electric discharge, chemical action of,Electrical properties of pure solvents,Electricity, atomic charge of, 267.Electrochemical analysis, 170.Electrons, 267.Elements, atomic heats of, 16.specific heats of, 14, 16.Enzymes, 148.analysis of, 182.Epidote, 243.Etholides, 141.Ethyl ether, electrical properties of, 22.Ethylene, trichloro-, solvent propertiesEthylidenesalicylamides, stereoisomeric,interaction of hydrogen and, 45.estimation of, 166.33:21,.of, 159.95.Euxenite, 243.Fahlerz, 243.Fats, analysis of, 177.Felspar group, 244.Fergusonite, 244.Ferrous salts, union of nitric oxideand, 56.Flames, electrical conductivity of, 33.Fluorescence, 259.Food analysis, 173.Forensic analysis, 183.Formaldehyde, detection of, 172.Friedelite, 244.Fructose, condensation of acetone and,107.Gageite, 236.Garnet group, 244.Gas analysis, 160.Gases, explosion of, 31.ignition-points of, 32.molecular heats of, 19.refractive indices of, 20, 160.separation of, 160.solubility of, in metals and alloys, 43.specific heats of, 17.inactive, constants of, 21.viscosities of, 20.cycloGeraniolene, 122.Glass, alkalinity of, 169.Glauconite, 245.Glutaconic. acids, substituted, stereo-Gold alloys with magnesium, 42.Goldfieldite, 235.Grahamite, 245.Grignard’s reaction, application of, 98.Haematin, 132.Halogens, estimation of, 163.Hambergite, 245.Hantzsch-Werner hypothesis, 93.Helium, molecular weight of, 30.rate of production of, from radium,Hetoerolite, 245.Hexane, liquid, electrical properties of,*ycZoHexanone-4-carboxylic acid, oximeHulsite, 245.Humboldtine, 246.Hydrates.See Salt hydrates.Hydrazine, preparation of, 53.Hydrides, formation of, 44.Hydrocarbons, action of, on mag-Hydrochloric acid, transport numberisorneric, 89.estimation of, 169.262.21.oi‘, resolution of, 94.nesium, 47.of, 24.synthesis of, 102INDEX OF STJBJECTS. 301Hgdrogen, ignition of oxygen and, 31.Hydrogiobertite, 246.Hydroxy-ketones, preparation of, 97.interaction of chlorine and, 45.union of oxygen and, 32.Ice, forms of, 1.Ignition-points, of gases, 32.Indicators, 161.Iodine, molecular condition of, 29.molecular weight of, 5.Ionisation, 24.Ioniuin, 275.Iron, cementation of, 42.Isomeric change, 153.Ixiolite, 246.rusting of, 37.Jnrosite group. 246.Joaquinite, 237.Raolinite, 246.Keten compounds, 72.Ketones, detection of, 172.molecular weights of, 5.Kryptotile, 247.Lactones,.preparation of, 98.Langbeinite, 248.Lansfordite, 248.Lanthanite, 248.Lead, estimation of, 165, 171.Lithium, atomic weight of, 26.Ludgwigite, 248.estimation of, 181.Magnesium, action of hydrocarbons on,Manganese, estimation of, 167.Manganosite, 248.Manures, 219.Mercury, atomic weight of, 27.Mesolite, 253.Mesothorium, 281.Metallic compounds, contact action of,47.alloys with gold, 42.alloys with silver, 43.estimation of, 165.99. _ _ _Metals, analytical reactions of, 159,162, 165, 180.atomic heats of. 17.contact actions of, 99.preparation of, 39.Meteorites, 254.Methane, estimation of, 160.Mica group, 249.Microlite, 249.Minerds.electrical conductivity of,synthesis of, 50, 102.228escape of helium from, 262.physical chemistrv of, 225.radioactivity of, 283.Minervitc, 249.Mingiietite, 237.Mosesite, 237.Molecular compounds, 6.weights, 29.Naphtha, pyrogenic decomposition of,Neon, molecular weight of, 30.Nepheiine, 249.Nesquehonite, 249.Nickel, estimation of, 166.Nitration, 96.Nitric acid, detection of, 162.Nitric oxide, union of ferrous saltsNitrides, metallic, 53.Nitriles, preparation of, 97.isoNitroamines, constitution of, 131.Kitrogen, estimation of, 175, 180.Non-metals, analytical reactions of,162, 163, 180.Nutrition, animal, 221.103.estimation of, 163.and, 56.stereochemistry of.91.Oils, analysis of, 177.Optical activity,and constitution, 86.Organic analysis, 172.Osazones, estimation of rotatory powerOxides, metallic, action of chlorine on,Oxonium compounds, 112.Oxygen, ignition of hydrogen and, 31.solubility of, in molten silver, 44.union of hydrogen and, 32.Ozone, decomposition of, 55.of, 160.54.Paigeite, 249.a-Particle, 259.Patronite, 249.Perphosphoric acids, 54.Persulphuric acid, preparation of, 56.Petroleum, analysis of, 179.origin of, 102.Phillipsite, 253.Phosphorus, varieties of, 53.new chloride of, 54.Photochemical reactions, 66302 INDEX OF SUBJECTS.Pilbarite, 237.Yilolite, 250.Plant, growing, chemistry of the, 214.Yleochroic halos, 260.Plumbo j arosite, 246.Plumboniobite, 250.Polonium, 281.Polypeptides, 146.Potassium, velocity of sound in vapourestimation of, 159, 168.iodide, molecular conductivity of, 24.mercuri-iodide, 35.of, 45.Prismatine, 250.Proteins, 146.analysis of, 182.Pucherite, 250.Pyroxene group, 250.Quercyite, 237.Racemic compounds, 83.Radioactive change, influence of teni-perature on, 273.Radioactive recoil, 271.R,adioactivity, atmospheric, 284.Radio-elements, chemical relationshipsof the, 285.Radium, preparation of, 40, 277.relation between uranium and, 275.emanation, 278.Radium-11, 280.a-Rays, 257.&Rays, 264.y-Rays, 268.Reaction, chemical, theory of, 60.Reduction, 96.Refractive indices of gases, 20.Resolution of acids and bases, 82.Respiration, 190.Rhabdite, 251.Rhodonite, 251.Rivotite, 251.Rocks, radioactivity of, 283.Rotatory power, influence of solventsnatural, 284.general organic, 96.on, 88.Salicylic acid, estimation of, 175.Salt ‘hydrates, 35.Salts, specific heats of, 15.solubility of sparingly soluble, 34.coloured, 76.fused, 225.Samsonite, 238.a-Santalol, 120.Sapphires, artificial, 50, 251.Scandium, compounds of, 50.Scapolite group, 251.Scatole, detection of, 172.Seligmannite, 252.Semicarbazones, stereoisomeric, 94.Silicates, constitution of, 228.fused, 225.Silicon monosulphide, 52.Silver, atomic v-eight of, 26.alloys with mercury, 43.estimation of, 165.chloride, solubility of, 34.photochlorides of, 46.carbonate, hydrates of, 36.physics of, 208.Sleeping sickness, 199.Sodium, estimation of, 168.Soil, bacteriology of, 212.Solution, 34.Solvents, influence of, on rotatoryorganic, behaviour of substances in,pure, electrical properties of, 21.Specific heats, 14.of gases, 17.Spectroscopy, 79.Starch, estimation of, 175.Steam, constitution of, 4.Stereochemistry, 82.Strontium, atomic weight of, 27.preparation of, 39, 40.Sulphur, molecular weight of, 5.compounds, phosphorescent, 152.organic derivatives of, 150.isomeric change in, 153.dioxide, electrical properties of, 22.ionisation of, 24.power, 88.34.Sulphuric acid, estimation of, 164.Tantalum, atomic weight of, 27.Tartaric acid, estimation of, 178.Tellurium, atomic weight of, 28.Terpenes, 116.Thermo-radioactivity, 271.Thorium, estimation of, 168.Thorium-D, 282.Tin, estimation of, 171.Titanium, estimation of, 168, 169.Toluene, chlorination of, 63.Toxicological analysis, 183.Transference numbers, 23.Triazens, 132.Triazo-compounds, 124.Triphenylmethyl compounds, 73.Tungsten, preparation of, 41.Turpentine, analysis of, 179.Ullmannite, 252INDEX OF SUBJECTS.303Unsaturation, influence of, 66.Uranium, relation between radiumand, 275Uranium-9, 273.Vanadate, new, 238.Vanadium, estimation of, 169.preparation of, 41.Vanthoffite, 252.Variscite, 252.Vesuvianite, 252.Viscosity, of inactive gases, 20.Walden inversion, 85.Wassermann's reaction, 196.Water, analysis of, 181.constitution of, 3.electrical properties of, 22.forms of, 1.theory of formation of, 33.of crystallisation, 34.Willemite, 252.Wiltshireite, 238.Wolframite, 253.Zinc, estimation of , 165.Zirconium, properties of, 41.H. C I A Y AND YON'S, LTD , BHEAD ST. BILL, E . C . , A S D BUNUAY, YL'FFOLK

ISSN:0365-6217    

DOI:10.1039/AR9100700299

出版商:RSC    

年代:1910

数据来源: RSC