摘要:

ANNUAL REPORTSON ' r mPROGRESS OF CHEMISTRYANNUAL REPORTS1L C. C. BALY, C.R.E., F.R.S.€3. M. DAWSON, D.Sc., Yh.D.J. C. IRVINE, D.Sc., Ph.D.F. GOWLAND HOPKIN8, M.A., M.B.,D.Sc., F.R.S.ON THEC. AINSWORTH MITCHELL, F.I.C.F. L. PYMAN, D.Sc., Ph.L).E. J. RUSSELL, O.B.E., D.Sc., F.R.S.F. SODDY, M.A., F.R.S.A. W. STEWART, D,Sc.PROGRESS OF CHEMISTRYF O R 191s.ISSUED BY THE CHEMICAL SOCIETY.6ommitttt of BubIiczrtion :tj. CIIASTOK CHAPMAS. J. C. PHILIP, O.B.E., D.Sc., Ph.l).A. W. CROSSLEX-, C.M.G., D.Sc., 1 SIR WILLIAM POPE, K . H . E . , N . A . ,M. 0. FORS~EH, Il.Sc., Ph.D., F.R.S. ’ F. L. YYMAN, D.Sc., P1i.D.A. HARDEN, D.Sc., Ph.D., F. K.S. A. SCOTT, M.A., D.Sc., F.R.S.’1’. A. HENRY, D.Sc. S. SMILES, O.B.E., D.Sc., F.R.S.C. A. KIGANE, D.Sc., Ph.D.i J. F. THOEPF., C.B.E., D.dc., 1’h.D ,G . T. MORGAN, D.Sc., F R.S.F.R.S. , D.Sc., F.R.S.F.R.8.&bitor :J. C. CAIN, D.Sc.Sub- Qbitor :A. J. GREENAWAY.,5JssiEltmt Snb-@Fbitux :CLARENCE SMITH, D. Sc.LONDON:GURNEY & J A C K S O N , 33, PATERNOSTER ROW, E.C. 4.1919PBIKTEb I N QBEIT BRITIIN BYRICHARD CLAr hh’D SONS, IAIYITED,BRUNSWICX STREET, STOdFORD STREET, Y.E. 1.ASD BUXQiY, SUFFOLHCOKTENTS.PAGEGENERAL AND YHPSICAL CHEMISTRY. By H. M. DAWSOX, D.Sc.,Ph.D. . . . . . . . . . . . . 1INORGANIC CHEMISTRY. By E. C. C. RALY, C l3. E., F.R.S. . . 26Part ~.-ALIPHATIC DITISIOS. By J . C. IRVIXE, D.Sc., Ph.D. - . . 48Part II.-HOMOCYCLIC DIVISIOS. By F. L. PYMAN, D.Sc., Ph.D. . . 73Part III.-HETF,ROCYCLIC DIVISION. By A.W. STEWART, D.Sc. . . 96ANALYTICAL CHEMISTRY. By C. AINSWORTH MITCHEIJ,, F I.C. . . 118PHYSIOLOGICAL CHEMISTRY.D.Sc., F.R.S. . . . . . . . . . . . 143By E. J. HUSSELL, O.H.E., D.Sc., F.R.S. . . . . . 172RADlOACTlVITY By FKEDEI~ICK Somy, M. A.,' F.R.S. . . . . 195ORGANIC CHEMISTRY :-By F. GOWLAND HOPRIM, M.A., M. EL,AGRICULTURAL CHEMISTRY AND VEGETA RLE PHYSIOLOGYTABLE OF ABBREVIATIONS EMPLOYED I N THEABBILls VZAT ED 'r IT LE.A . . . . . .Ayric. J. India . . .ilmer. C'hem. J. . .Amer. J. Sci. . . .Amer. J. Bot. . . .Amer. J. Physiol. . .Anal SOC. Qui~n. Aryenti?baAnalyst . . . .Annalen . . . .Ann. Bot. . . . .A m . China. . . .Anla. Chim. rtnal. . .Aunali Chim. Appl. . .Awnn. Ghim. Pfrys. . .Anit.Falsif. . , .A m . Physik . . .Ann. Report . . .14rch. Sci. phys. ntct . .Atti E. Accad. Liwci . .Be?. . . .Ber. Dezct. physikal. Ges. 1Berlin. KEin. Wuch. . .Biochem. J. . . ,Biochem. Zeitsch. , .Boll. clzim. farm . .Rot. Gaz. . . .Brit. ~ a i . 'J. . . .Byit. Pat. . . . .Bull. Assoc. Chiin. Sum.Bull. SOC. chim. . .Chem. Neus . . .G'km. Zeib. . . .Cbmpt. rend. . .C'omnples rend. Trav. Lnb.Curluberg . . .Fermentforsch. , , .Gccxzetta . . . , .Belt,. C'him. Acta .Jahrb. 12ndwaktiv. Ekk:tronik . . . .Jap. Pat. . . . .J. Agric. 38s. . . .D.8.-P. . . . .REFERENCES.JOU ENA L.Abstracts in Journal of the Chelnical Society.*Agricultural Journal of India.American Chemical Journal.American Journal of Science.American Journal of Botany.American Jouri~t~l of l'hysiologv.Anales de la Sociedad Qutmica Argeatiiia.The Analyst.Justus Liebig's Annalen der Chemie.Annals of Botany.Annales de Chimie.Annales de Chimie analytique appliqu6e A l'lndustiie,Annali di Chimica Applicata.Annales de Chimie et de Physique.hnnales des Falsifications.Annnlen der Physik.Annual Reports of the Chemical Society.Archives des Sciences physiques e t natnrellvs.Atti della Reale Accademia dei Lincei.Berichte der Deutschen chemischen GesellschaftBerichte der Deutsclien physikalisclien Gesellsclixft.Berliner Klinische Wochenschr~f't.The Biochemical Journal.Biochemische Zeitschrift.Bolletino chimico farmscentico.Botanical Gazette.British Medical Journal.British Patent.Bullet in de 1'Association des Chimistes de SucrerieBulletin de la SociQt6 chimique de France.Chemical News.Chemiker Zeitung.Comptes rendus hebdomaclaires cies Sdanceu deComptes rendus des Travanx de Laboratoii e de tarls-Deutscties Reichs-Patent.Ferru entforschunp.Gazzetta chimica italiana.Helvetica Chimica Acta.Jahrbuch der Radioaktivitat und Elektronik.B I'Agriculture, B la Pharniacie et h la Riologie.et de Distillerie.l'Acad6mie des Sciences.herg.Japanese Patent.Journal of Agricultural Research.The year is not inserted in references t o 1918viii TABLE OF ABBREVIATIONS EMPLOYED IN THE REFERENCES.ABBREVIATED TITLE.J Aqric.&i. . . .J. Amer. Chcm. SOC. . .J. Biol. Chein. . . .J. B d . Agric. .. .J. Chein,. Ind., Tokyo. ,.J. Exp. Med. . . .eJ. Rrmaklin Inst. . .J. Zmrnun.. . . .J. Ind. Eng Chm. , ..I infec. Dss. , . .J. Landw. . . . .J. Pharm.. Chim. . .J . Pharm. Expt. Ther. ..J. Thiszcal Chern. . ..J. Phiysio2. Path. gdn. . .j: pr. Chm. . . .J. Rontgen Soc. . . .J. R Q ~ . Agric. S'oc. . .J. SOC. Chem. IrLd. . ..L Tokyo Chem. SOC. . .J . Washington Acatl. Sci. .Kolloid Zeitxh. . .Krakmcr Anz. . . .Lamet . . .Medd. K. Vetenskapsakad.Nobel-lmf. . . ..L Physiol. . .Mm. C01l. SC~. Ky6tdMon. Sci. . . , .Zonth. Not. Roy. Aslr. Soc.P. . . . :.PJuger's Archiv . . .Pharm. Weekblad . .Pharm, Zeit. . . .Philippine J. Sci. . .Phil. Mag. . . .Phil. Trans. . . .Physikal. Zeitch. . .Physiol. Abstr.. . ,Plzysiol. Research . .Proc. K. Aknd. 1Veten.rch.Ainstsrdnin. . . .Proc. Nab. Acnd. Sci. . .Proc. Physical Soe. London.Proc. Yhysiol. floe. . 'Proc. Boy. A'OC. . . .Proe. Roy. Soc. Edin. .Quart. J . exp. PhysioZ. .Rec. trav. chim. . . .Rep. Brit. Aasoc. . .JOURNAL.Journal of Agricultural Science..Tournal of the American Chemical Society.Journal of Biological Chemistrv, New York..Tournal of the Board of Agriculture.Journal of Chemical Industry, Tokyo.Journal of Experimental Medicine..Journal of the Franklin Institute.Journal of Immunity..Tournal of Industrial and Etigineering Chemistry.Journal of infectious Diseases.dourual fur Landwirtschaft.Journal de Pharmacie et de Chimie.Journal of Pharmacology and Experimental Thera-Journal of Physical Chemistry.Journal of Physiology.Journal d0 Physiologie et de Pathologie g6nQrale.Journal fiir praktische Chemie.Journal of the Kontgen Society.Journal of the Royal Agricultural Society.Journal of the Society of Chemical Industry.Journal of the Tokyo Chemical Society.Journal of the Washington Academy of Sciences.Kolloid Zeitschrift.Krakauer Anzeiger.The Lancet.Meddulanden fran Kongl.VetenskapsakademiensMemoirs of the College of Science, Kyat6 ImperialMonatshefte fur Chemie und verwandte Theile andererMoniteur Scientifique.Monthly Notices of the Royal Astronomical Society,Proceedings of the Chemical Society.Archiv fiir das gesammte Physiologie des MenschenPharmacrutisc ti Weekblad.Pharmazeutische Zeitung.Philippine Journal of Science.Philosophical Magazine (The London, Edinburgh andPhilosophical Transactions of the Royal Society ofPhysikalische ZeitschriftPhysiological Abstracts.Physiological Kesearch.Koninklijke Akademie van Wetenschappen te Amster-dam. Proceedings (English version).Proceodings of the National Academy of Sciences.Proceedings of the Physical Society of Lotidon.Proceedings of tohe Physiological Society.Proceedings of the Royal Society.Proceedings of the Royal Society of.Edinburgh.Quarterlv Journal of Exprrimental Physiology.ltdcueil des travaux chimiques des Pays- Bas et . de laReport of t h e British Association for tlic Advance-peutics.Nobel- Insti tu t.University.Wissenschaften.London.und der Thiere.Dublin).London.Relgique.ment of ScienceTABLE OF' AHRREVIATlONS EMPLOYED IN I'HE REFERENCES.1X8 E 131; EVI A '1'ED TITLE.soil Sci. . . .T . . . . .Trans. Yaraday Soc. .Yrmis. Xqr. ,Yoc. CanatinWien. ilfcd. Wocl~.Zcitsch. anal. Chem. .Zcitsch. a?&ge.a. Chent.Zeitsch. nnorg. Chem. .Zeitsch. Elektroclimn. .Zeeitseh. Nahr.- GemtsumZeitsch. o$enlZ. C'hein .Zeitsch. physikal. Chem.Zeituch . physio 1. Che m.Zeitsch . wiss. Ph 01 uch e m.J O ~ ~ R N A L .Soil Science.Transactions of the Chemical Society.'rransactions of the Fsradny Society.Transactions of the Koyal Society of Canada.Wiener M edizinische Wochenschrift .Zeitschrift fur analytische Chemie.Zeitschrift fur angewaiidte Chemie.Zeitschiift fiir anorganisclie uud allgerneine Chemie.ZeitschriR fur Elektrochemie.Zeitschrift fiir Untersuchnng cler Nahriings- untlZvi tschrift fiir o ffen tliche Chemie.Zeitschrift fur physikalische Chemie, Stochiometrieund Verwaiilritschafts1ehl.t:Hopye-Seyler's Zeit.;chrift fiir yhysiologische Chernie.Zeitschrift iur wissenschaftliche Photographic, Photo-phi sik uiid t'hotochexriie.%entr;~lblat t fiir Physiologie.Zentralblatt fur Zuckerintlustrie.Gennsmittel

ISSN:0365-6217    

DOI:10.1039/AR91815FP001

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

INORGANIC CHEMISTRY.THE diminution in the number of papers that come under reviewin this branch is very marked. With few exceptions, the work ininorganic chemistry during 1918 has been restricted to the pre-paration of new substances. There is little t o record of outstand-ing interest beyond the preparation of the hydrides of silicon andsome of their halogen and oxygen derivatives.Allotropy.Some further work on the allotropy of sulphur may be referredt0.l The discovery of the third modification of sulphur, namely,S,, was dealt with in the Report for 1913, the method of pre-paration being to heat sulphur a t 170° and then to cool it rapidly.The sulphur is then dissolved in carbon disulphide and cooled to-80°, when the whole of the S, separates out, leaving the S , insolution.By careful evaporation of this solution in a vacuuma t -80°, the S, is obtained, contaminated with only a very smallquantity of Sp. It is clear, therefore, that S, is formed from S,a t 1 7 0 O . It has now been found that the equilibrium between thetwo forms is obtained more rapidly in sulphur chloride solutionthan in toluene. A t 140°, six hours are required in the case oftoluene, whereas equilibrium is reached in a few minutes in sulphurchloride solution. Some quantitative investigations have beenmade of the amount of S,, formed under varying conditions oftemperature and concentration. Solutions of sulphur in toluene,in which the equilibrium between S, and S,, had been establishedby heating a t 140°, 150°, and 160°, were cooled to Oo and stirredfor an hour in contact with rhombic sulphur. The resulting solu-tions were analysed, and it was found that the proportion of Sincreases with the temperature and also slightly with the con-centration.There is no doubt that the discovery of this new form of sulphurA.H. W. Aten, Proc. K. Akad. Wetensch. Amsterdam, 1918, 20, 824 ;A., 5, 193.2INORGANIC CHEMISTRY. 27which is clearly produced from S, a t temperatures above the melt-ing point must alter our ideas, as to the composition of moltensulphur. For example, it has commonly been believed that thenatural freezing point of sulphur is lower than that of pure rhmbicsulphur, S,, owing to the presence of about 3.7 per cent. ofamorphous sulphur, S.2. Since S, is partly converted into S,,,i t is evident that the latter must be present in sulphur a t its melt-ing point, and the question atl once arises as to how far the naturalfreezing point of sulphur is due to the presence of S, Thisquestion has been very definitely answered, for it has been foundthat S,, is the sole factor in depressing the freezing point ofs,3It was necessary in the first' place to determine the cryoscopicconstant of sulphur, and this was carried out without much diffi-culty, since sulphur can be used as a cryoscopic solvent i f certainconditions are fulfilled.Soon after it has been melted, the freez-ing point of sulphur is about 119O, but after it has been kept forsome hours a t a temperature just .above its melting point,, thefreezing point falls to the natural freezing point, 114-5O.I n thiscondition, the sulphur is suitable for cryoscopic determinations.The cryoscopic constant was determined by means of a number oforganic compounds, the mean value being 213. The actual deter-minations were : bromoform 229.3, phenylthiocarbimide 226.6,naphthalene 211.4, diphenyl 208-4, thymol 206.4, quinoline 205.7,&naphthol 205.2, and aniline 201-8.Now the freezing point of S, is 119*25O, whilst the natural freez-ing point is 1 1 4 ~ 5 ~ . Assuming that the depression of 4'75O is dueto the presence of S,, with a molecular weight of 128, the propor-tion of S, present must be 2.78 per cent. I n order ,to test whetherthis assumption is justified, some experiments were made on theeffect of the addition of various forms of sulphur to sulphur offreezing point 114.5O. Amorphous sulphur, S,, prepared in avariety of ways, has practically no effect on the freezing point, andthis is due to the rapid transformation of the S, t o a mixture ofS, and S, of the same composition as the solvent sulphur. If thesolution is rapidly cooled after the addition of the S,, it is foundthat only about 24 per cent.of the added sulphur is still insolublein carbon disulphide, the remainder having been transformed intoS, and 53,. When S, is added to a fused mass having a lowerA. Smith and C. M. Carson, Proc. Roy. SOC. Edin., 1906, 26, 362; A.,E. Beckmann and C. Platzmann, Zeitsch. anorg. Chem., 1918, 102, 201 ;E. Beokmann, R.Paul, and 0. Liesche, &id:, 1918,103, 189; A., ii, 308.1907, ii, 20.A . , ii, 21828 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRYfreexing point than 114-5O, there is no effect, but if it is added toone having a higher freezing point than 114*5O, it has the effectof lowering it towards the natural freezing paint, indicating thata t the higher temperature relatively more 8, is formed fromthe S,.When S, is heated, it shows no sharp melting point, but, havingreached 120°, it has a t once t'he natural freezing point 114.5O. If amixture of rhombic sulphur with about 5 per cent. of SN is melted,i t has a freezing point about 2O lower than that of rhombicsulphur, indicating that under these conditions the S, decomposesinto 23 per cent. S, and 77 per cent.S,. A sample of S, whenadded to sulphur with the natural freezing point lowered thefreezing point slightly, but the depression indicated only about4.6 per cent. S, in t,he sample. Lastly, it, was observed that bothrhombic and monoclinic sulphur raised the natural freezing pointof sulphur by increasing the proportion of S,.It may not be out of place to direct attention here to theremarkable colour gradation exhibited by the various allotropicmodifications of sulphur in solution. It has now been definitelyrecognised that there are four distinct modifications, namely, S,,Spy S , and Sb, and of these S, is known as the ordinary rhombicand monoclinic varieties. When S, is maintained a t temperaturesof 119-170°, it is partly transformed into S,,, the molten massbeing an equilibrium mixture of S, and S,.the proportion of S,,being increased with rise of temperature. A t temperatures of250-300°, €3, is formed, for it is a simple matter t o prove bysudden cooling that a considerable proportion is insoluble incarbon disulphide. Clearly, therefore, S,, and S, are formed bythe supply of energy to S,, and although both are known in thesolid state, they obviously are metastable. Tzlis is proved by thereadiness with which S, is converted into S, and S, by solutionin molten sulphur maintained a t 120°, as described above.S+ is precipitated along with S, when certain sulphur com-pounds, such as sodium thiosulphate, are treated with mineralacid, and from this alone the relative energy contents of S+ andS, cannot be ascertained.Now it is well known that a solution of S, in carbon disulphideis practically colourless, and, further, a solution of S, in toluenehas a colour analogous to that of a concentrated solution ofpotassium chromate.It is not generally known that S, is solublein piperidine, and the solution has a fine red colour analogous tothe colour of molten sulphur a t a temperature of 250-300O.Since molten sulphur a t 250-300° contains 8, as an importantconstituent of the equilibrium, this identity of colour is not surINORGANlC CHEMISTRY. 29prising. Again, S, is soluble in piperidine, and the solution hasthe same colour as when S, is dissolved in that solvent, and thusit is evident that piperidine converts S, into S, Further onneutralising the piperidine solution with acid, the dissolved sulphuris recovered as S,.We have, therefore, three differently coloured solutions ofsulphur, namely, the almost colourless solution of S, in carbondisulphide, the strongly yellow solution of S , in toluene, and thedeep red solution of S+ in piperidine.This deepening of thecolour, coupled with the knowledge that the energy content' in-creases from s, to 8, to s,, is very suggestive. It is exactly analogousto the cases of many organic compounds which exhibit differentcolours in different solvents, according to the amount of energysupplied to them by the solvents. According t o this argument, S,+must have an energy content between those of S, aiid S,, since itssolutions exhibit a colour intermediate between those of the solu-tions of these two.The colour of the various phases of sulphur would seem to havea bearing on the constitution of the sulphides and the poly-sulphides. The anhydrous monosulphides of the alkali metals arepractically white, the disulphides pale yellow, the tetrasulphidesdeep yellow, and the pentasulphides orange.I n short, the coloursare analogous to those of the four modifications or phases ofsulphur when in solution. The suggestion may a t once be madethat the phases in which the sulphur exists i n the four types ofsulphides corresponds with the four phases of sulphur, S,, 8,+, S,,and S,. Considerable support for this is to be found in the factthat the pentasulphides, on treatment with acids, give a pre-cipitate of S,.Colloids.ilnioiigst the papers on colloids that have been published duringthe last twelve months, a few have described the preparation ofinorganic colloids.Colloidal solutions of nickel can be prepared by the reductionof solutions or suspensions of nickel salts in glycerol containinggelatin or gum arabic as a protective colloid.6 Thus, a solutionof nickel formate and gelatin in glycerol a t 200-210° when sub-mitted to the action of a stream of hydrogen assumes a chestnut-brown colour.The colloidal solution remains unaltered in airand is miscible with alcohol. On tlreatment with water andcentrifuging, the colloidal metal is deposited as a brown solid con-t.aining 25 to 30 per cent.of nickel. This again yields colloidalC. Kelber, Ber., 1917, 50, 1509; A,, ii, 1930 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.nickel solutions in dilute acetic acid, acidified water, glycerol, oralcohol.Hydrazine hydrate, formaldehyde, hydroxylamine, and hypo-phosphorous acid can be used as reducing agent, and the nickelformate can be replaced by nickel acetate or freshly precipitatednickel hydroxide.A variety of methods have been described for the preparationof mercury sols: and the methods may be grouped into threeclasses, namely, mechanical, thermal, and electrical dispersion. Byforcing a fine stream of mercury by means of high pressure intosolutions of gelatin and potassium nitrate, definite mercury solsare produced, although the particles are relatively large.Whenmercury is shaken with very dilute solutions (10--5A-) of ammonia,ammonium sulphate, ammonium chloride, calcium citrate, tartaricacid, potassium tartrate, carbamide, or gelatin, colloidal mercurysolutions are produced.Mercury sols are also formed by passing hot mercury vapourdirectly into water. They can also be prepared by the Bredigmethod, using either a direct or an alternating current.The sols have varying colours from grey to yellowish-brown andreddish-brown. They are all positively charged except those pre-pared in citrate or tartrate solutions, which are negatively charged.Reference may also be made to an import'ant investigation ofthe nature and stability of hydrated ferric oxide sols.7 Severalseries of perfectly clear sols were prepared, the iron concentrationin each being constant, whilst the chlorine content varied.Thesols were prepared by oxidising a solution of ferrous chloride con-taining 1 gram equivalent .in 400 C.C. of solution by means of3 per cent. hydrogen peroxide. The solutions were then dialysedand diluted to the required concentration.The sols were precipitated by potassium sulphate solution, andthe amount of salt required for the complete precipitation of thesol was taken as a measure of its relative stability. The resultsshow that f o r a given iron concentration the stability increaseswith the chlorine concentration, whilst. for sols of a given purity,that is, for sols with the same ratio, Fe/Cl, the stability decreasesas the concentration increases, this being most pronounced in verypure sols.A theory based on the existence of d0finit.e oxychlorides as com-ponents of the colloid equilibrium was put forward by Nicolardot,86 I.Nordlund, D&78., Upda, 1918, 1 ; A., ii, 267.7 M. Neidle, J . Amer. Chem. SOC., 1917, 39, 2334 ; A., ii, 46.OP. Nicolardot, Compt. rend., 1906, 11M), 310; Ann. Chim. Phy8., 1906,[viii], 6, 334 ; A., 1905, ii, 167INORGANIC CHEMISTKY. 31who believed that two such oxychlorides exist with ratios FejC1of 6 and 125. The experimental data are now criticised and thetheory is modified. The first stage in the hydrolysis of ferricchloride is to be represented by the equationFerric chloride + water colloid No. 1 + hydrochloric acid,colloid No.1 being an oxychloride in which the ratio, Fe/Cl, is 21.It is believed that all clear, hydrated ferric oxide sols containingferric iron contain this definite oxychloride as a component of theequilibrium.As the concentration of ferric ion is decreased, this colloidaloxychloride begins to hydrolyse, giving hydrochloric acid and asecond oxychloride, colloid No. 2, with a ratio greater than 21.When the sol no longer contains ferric ion, the progressive removalof the hydrochloric acid causes a series of successive hydrolyseswhich overlap to a certain extent, and oxychlorides of increasingmolecular weight are formed.The hydrolysis equilibria of the oxychlorides are establishedrapidly, but the establishment of t'he first hydrolytic equilibriumbetween ferric chloride and colloid No.1 requires considerabletime.G r m p 1.Some new investigations have been carried out. on sodamide andpotassamide.Q These compounds were prepared by the action ofammonia on the molten metals, and their physical constants weredetermined immediately after preparation. The melting pointswere found from cooling curves to be NaNH, 210°, KNH, 33S0,these being much higher than those found by Titherley,lo namely,NaNH, 149-155O and KNH, 270-272'. No other breaks werefound in the cooling curves. The fused amides conduct electro-lytically owing to their ionisation into Na' and NH,'. Hydrazine,however, is not formed a t the anode, but ammonia and nihogen,owing probably to the action of the amide.Chlorine and iodinedo not give hydrazine with these compoundst but halogen-sub-stituted ammonias.Certain mixed polyhaloid salts of ammonium and the alkalimetals have been prepared.ll It has been known for some timethat by the action of bromine vapour on ammonium iodide, thebromoiodo-bromide, NTI,BrIBr, is formed.f2 Although a t theL. W6hler and F. Stang-Lund, Zeitsch. ElektrocAem., 1918, 24, 261 ; A.,ii, 397. lo A. W. Titherley, T., 1894, 65, 604.l1 W. N. Rae, {bid., 1915,107, 1286; 1918,113, 880.C. L. Jackson and I. H. Deny, Amer. Chcm. J., 1900, 24, 35 ; A., 1900,ii, 59632 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.commencement of the reaction iodine is set free, this substance ienot a mixture of ammonium bromide and iodine bromide, but adefinite compound.Exactly analogous compounds are formed bythe slow action of bromine vapour on potassium, rubidium, andmiurn iodides These substances are ruby-red in colour anddeepen in shade with rise in atomic weight of the metal. Whenheated, they lose iodine monobromide and give the normal bromide.By the action of chlorine13 on concentrated solutions of theiodides of the alkali metals, the compounds MICl, have alreadybeen prepared, and two of these salts have water of crystallisatGion,namely, LiIC1,,4H20 and NaJC1,,2H20. By the action of drychlorine on the dry iodides, these salts have been prepared in theanhydrous condition, their colour varying from deep orange in thecase of the lithium salt to mustard-yellow in the case of theccesium salt.The lithium salt, however, could not be obtained inthe anhydrous condition, and the hydrate, LiIC1,,3H20, was pre-pared. Although the rate of absorption of the chlorine falls offas the formation of the pentahaloid approaches completion, thetime c’urve shows no break. On the other hand, when these saltsare gently heated, they lose chlorine and are ,converted into thetrihaloid salts, MI(&. The latter compounds are much morestable than the pentahaloid salts and require to be heated a t ahigher temperature in order to give- the normal chloride with lossof iodine monochloride.Mention may be made of an extension of the work that haspreviously been reported on the sulphides of sodium andpotassium.l4 The investigation has naw been carried to the poly-sulphides of these two metals, two experimental methods havingbeen adopted.I n one, the rate was measured a t which sodiumt.etrasulphide and potassium pentasulphide lose sulphur whenheated in a steady stream of hydrogen, and in the other the freez-ing-point curves for the systems Na,S-S and K,S-S were deter-mined. The results obtained are of some interest, for definiteevidence was forthcoming of the existence of a complete series ofcompounds of the general formula R2S,, where x is a whole numberand has the maximum value 5 in the sodium series and 6 in thepotassium series. No evidence whatever was found of the exist-ence of any intermediate compounds, such as the enneasulphide,Na,S9, described by Bloxam. In connexion with the desulphur-isation of the polysulphides, the disulphides were found to beextremely stable compounds from which sulphur can only beremoved with difficulty a t 700-800°.la H.L. Wells and H. L. Wheeler, Amer. J . Sei., 1892, [iii], 44, 42 ; A.,1893, ii, 68. l4 J. is. Thomas and A. Rule, T., 1917,111, 1063IN 0 ROAN 1 C CH EM 1 S‘I‘RY. 33In order to decide between the simple formula R,S, and thedoubled formula R4SZz, favoured by Bloxam, the molecularweights of sodium disulphide and ‘tetrasulphide and potassiumpentasulphido were determined by the ebullimcopic method wit-halcohol as a solvent. The results obtained were considerably lowereven t,han those required by the simpler formuke. The greencolsur of the solutions suggests that a certain aimunt of alcoholysisoccurs, but as very little hydrogen sulphide is lo& by the boilingsolution, it is probable that.tho discrepancy is not due to thiscause. I n all probability, the explanation is to be found inionisation having occurred, and a t any rate it is evident that thesimpler formula, R,S,, must be correct.The relative stability of the disulphides a t once suggests thattheir constitution is t o be represented by R-S*S*R. From this, thepolysulphides are obtained, not by solution of sulphur, but by - . - S S 8R.’&$.:’.K further combination t o ittltl lbS* S . HIt has bee11 found that the commercial basic carbonates ofcopper differ very considerably in composition, and i t is erroneousto assume that they approximate t o the coniposition of malachite.ljAn analysis of thirteen samples from cliff erent commercial sourcesshowed t,hat the percentage OF copper oxide varied from 78.6 t o66.2, and from this point of view i t would seem that the composi-tion more nearly approximates to that of azurite.The amountof carbon dioxide present, on the other hand, is much below thatrequired for either malachite or azurite. Some attempts t o pre-pare a basic carbonate of copper of approximately constant com-position by mixing solutions of copper sulpbate and sodiumcarbonate or sodium hydrogen carbonate led to negative results.It. has been found, however, that a definite basic salt is obtainedin the following way. A solution of copper sulphate, saturated atj1 4 * 5 O , is diluted with an equal volume of water, and to this solu-tion is added a solution containing 5 per cent.of sodium carbonateand 5 per cent. of sodium hydrogen carbonate until precipitation iscomplete. The mixture is allowed to remain for twelve hoursand then filtered. The precipitate is washed free from sulphate,a process which takes many hours. The wet precipitate is allowedto remain for another twelve hours, and then is dried in a steam-oven for a t least six hours. The formula of the salt. prepared inthis way is 2CuCOs,5Cu(OH), or 7Cu0,2C0,,5H20.H. B. Dunnioliff and S. Lal, T., 1918, 113, 718.34 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Croup 11.When solutions of magnesium chloride and disodium, di-potassium, or dirubidium hydrogen phosphate are broughttogether, magnesium hydrogen phosphate generally is precipitated.This salt has a variable content of water of crystallisation, but isliable t.0 be contaminated with magnesium monoalkali phosphate,and under suitable conditions the whole of the precipitate mayconsist of the latter type of salt.16 For example, when a dilutesolution of magnesium chloride is added slowly with agitation t.0a 10 per cent, solution of dipotassium hydrogen phosphate, thesalt, MgKPO,,GH,O, is precipitated in almost pure condition.The orresponding rubidium salt can be precipitated almost purein a similar manner. If the two solutions are mixed in the reverseorder, the precipitate obtained is of uncertain composition, con-taining various quantities of MgKPO,, MgHPO,, Mg(OH),, andMg3(P0,),.In whatever manner dilute solutions of magnesiumchloride and disodium hydrogen phosphate are mixed, there is adanger of the magnesium hydrogen phosphate being contaminatedwith magnesium alkali phosphate. This has a bearing on theestimation of phosphoric acid by the magnesium method, since itis desirable to guard against the presence of alkali metal salts.Calcium hydrogen arsenate can be prepared by pouring a solu-tion of calcium chloride, slightly acidified with acetic acid, hydro.chloric acid, or nitric acid, into a solution of disodium hydrogenarsenate similarly acidified .17 The precipitate is washed bydecantation, filtered, washed until free from chlorides, and drieda t looo. The composition of the salt, is CaHAs0,,H20, the waterof crystallisation being lost a t 1 7 5 O .By the addition of an alkaline solution of calcium chloride toan alkaline solution of disodium hydrogen arsenate, pure calciumarsenate, Ca3(AsO,),,2H,O, is obtained, which can be dried a t looo.An important contribution to the literature on mercuri-ammonium compounds may be noted.18 There are three classesof these substances, namely: (i) the additive compounds ofmercuric salts and ammonia, of which fusible precipitate,HgCl,,2NH3, is the best known example; (ii) the ammonolysedcompounds in which NH,, NH, or N takes the place of the acidradicle in a mercuric salt, ' of which infusible precipitate,ClHgNH,, is the simplest representative ; (iii) the compounds16 D.Balareff, Zeitsch. anorg. Chern., 1918, 102, 241 ; A., ii, 266.1' R. H. Robinson, J . Agric. Rm., 1918, 13, 281 ; A., ii, 232.18 Miss M. C. C. Holmes, T., 1918,113, 74INORGANIC CHEMISTRY. 35whi& are both hydrolysed and ammonolysed, sI1ch as the chlorideof Millon’s base, H,N*Hg-O*HgCl.BY the action of gaseous ammonia on mercuric: chloride, fusibleprecipitate is formed, and this compound can also be obtained bydissolving infusible precipitate or the chloride of Millon’s base ina hot saturated solution of ammonium chloride and cooling thesolution. Some experiments carried out on the action of dryammonia on an ethereal, solution of mercuric chloride indicatedthat a lower arnine of mercuric chloride must exist. When in-fusible precipitate is digested a t looo with solutions of mercuricchloride in approximately saturated solutions of ammoniumchloride, the solution being filtered while hot from the undis-solved precipitate, the filtrate, on being allowed to cool, slowlydeposits well-defined crystals. The composition of these crystaledepends on the concentration of the mercuric chloride.When thelatter amounts to 110 grams in 100 grams of water containing42 grams of ammonium chloride, the new compound, 3HgC1,,2NH3,is obtained. With smaller concentrations of mercuric chloride,fusible precipitate is formed, and no compounds intermediatebetween these two appear to exist.Some doubt has been thrown 011 the existence of the canpound,HgCl,,NH,*HgCl, but i t is now found that! this substance is pro-duced by heat.ing infusible precipitate with a dilute solution ofammonium chloride, nearly saturated with mercuric chloride, a tlooo for one or two hours.The solution is filtered and allowed tocool, when the compound separates in the form of a fine, whitepowder.Group 111.Brief reference may be made to some work on boron and someof its compounds.1g The usual methods for the preparation of thiselement by the reduction of the oxide or chloride by metals areunsatisfactory, since the product invariably contains boride. Thepurest boron is obtained by the reduction of boron trichloridewith hydrogen in the high tension electric arc. A new boronnitride, probably B,N, has been prepared by heating boric acidwith magnesium nitride.The ordinary nitride, BN, is con-veniently obtained from boric acid and calcium cyanamide. Whenthe vapour of boron trichloride is passed over red phosphorus inthe presence of oxygen, a phosphate is formed having the formula2B,O,P,O5, and other phosphates also appear t o exist.l9 W. Kroll, Zeitmh. anorg. Chem., 1918, 102, 1 ; A., ii, 10936 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Following on his work on the hydrides of boron, Shock, duringthe past three years, has undertaken the investigation of thehydrides of silicon. The following nomenclature of these com-pounds has been adopted.20 The saturated compounds are termedsilanes, the various members being differentiated thus : SiH,monosilane, Si,H, disilane, Si,H, trisilane, etc.The names of theother silicon compounds are derived from these in the usualrat,ional manner of organic nomenclature. Thus Si,H,, Si,H2would be termed disilene and disiline respectively. The oxygenderivatives are named siloxanes ; thus SiH,O protosiloxane (uxo-monosilane) and (SiH,),O disiloxane.The silanes have been obtained by the action of acid on mag-nesium silicide, the yield depending on the manner in which thembstance has been prepared.21> 29 The best conditions are gainedby using magnesium and silica in the proportions o f 2 : 1, the lattersubstance being obtained by heat.ing the hydrated compound.The hydrated silica should contain 0.3-0.5 per cent. of impuri-ties, -because this prevents the dehydra+t.ed substance from beingt.oo finely divided.About 100 grams of the mixture are used, andafter the reaction has commenced the crucible is covered with alid through which hydrogen is passed until the mass has cooled.The product is a blue, crystalline mass.It is important that the silicide should be t,reat,ed directly withacid, and not first to add water, since the silanes are extremelyreadily acted on by alkali. The gases evolved are washed withwater, dried with calcium chloride and phosphoric oxide, and thencondensed in a tube cooled by liquid air. By careful fraction-ation the first four silanes are obtained in a pure state, thesparingly volatile residue probably consisting of pentasilane,Si5HI2, and hexasilane, SIGH,,. About one-quarter of the silicoiipresent as silicide is obtained in the form of hydrides, theremainder being converted into " silico-oxalic acid ."Monosilane, SiH,, melts at - 1 8 5 O and boils at. - 112O/760 mm.It is a colourless gas which is very stable at the ordinarytemperature, and its spontaneous inflammation in the air is un-certain, small bubbles, as a rule, failing t o catch fire.Thea* A. Stock, Ber., 1916, 48, 108 ; A., 1916, ii, 319.81 A. Stock and C. Somimki, ibid., 111 ; A., 1916, ii. 319 ; ibid,, 1917, 60,1739 ; A., ii, 110 ; ibid., 1918, 51, 989 ; A., ii, 361.22 A. Stock, C. Somieski, and R. Wintgen., ibid., 1917, 50, 1754, 1764 ;A., ii, 110, 111INOfCGANlC CHEMISTRY. 37presence of other hydrides of silicon causes it invariably to inflame.The vapour density a t 1 9 O is 16.02.Disilane, Si,H,, melts a t - 1 3 2 ~ 5 ~ to a liquid which boik a t-15O/760 mm.It can be preserved unaltered at the ordinarytemperature, but, decomposes rapidly atl 3 0 0 O . The gas inflamesin the air sometimes with violent. explosion. It is very readilysoluble in benzene or carbon disulphide, but. the latter solution isspontaneously inflammable in air. With chloroform arid carbontatrachloride , vigorous reactions occur accompanied by flame.The vapour density of disilane at 21° is 31.7.Trisilane, Si,H,, 'is a crystalline solid melting at - 11F to acolourless, mobile liquid, and boiling at, 53O/760 rnrn. It is muchless stable than silane and disilane, decomposing a t the ordinarytemperatlure. The reaction with carbon tetrachloride is even moreviolent than in the case of disilane.Tetrasilane, Si,H,,, melts at- - 9 3 * 5 O to a colourless liquidboiling at' 80-90°/760 mm., and having a vapour density of 61.0.The stability is less than that of trisilane, for tetrasilane decom-poses fairly rapidly at the ordinary temperature.The two first' members of the series were aiialysed by themeasurement of the hydrogen evolved by the action of concen-hated sodium hydroxide solution, tqhe chemical changes being ex-pressed by SiH, + 2NaOH + H,O = Na2,Si0, + 4H, and Si2H, +4NaOH + 2Hz0 == 2Na,SiO, + 7H,.The composition of the otherhydrides was proved by decomposition by slow passage through aquartz tube a t 800-900O.The reaction between silaiie and bromine is very violent, but ifan excess of the gas is led into a vessel maintained at, -8OO t o-70°, on the walls of which solid bromine is deposited, the reac-tion can be controlled.In this way, the mono- and di-substitutedderivatives have been obtained.Broniomonosilane, SiHsBr, melts a t - 9 4 O and boils a t 1 * 9 O /760 m., forming a colourless gas. It may be preserved overmercury for s m e time, but it det'onates on exposure t o the air,giving silicic acid and brown silicon. With concentrated sodiumhydroxide solution, it reacts according to the equation SiH,Br +3NaOH = 3H, + NaBr + Na,SiO,.Dibromomolnosilane, SiH,Br,, melts a t - 70*lo t o a colourless,mobile liquid, and boils a t 66O/760 mm. It inflames in the airand is very sensitive to moisture, being decomposed into hydrogenbromide and a solid, (SiH,O),.With alkali, it reacts as follows:SiH,Br, + 4NaOH = 2H, -t 2NaRr 4- Na,SiO, +- €I@. When bromo-monosilane is shaken with water, i t gives disiloxane, (SiH,),O. Thisis a colourless, odourless gas which does not inflame spontaneoiislg38 ANNUAL REPOKTS ON THE PROGRESS OF CHEMISTRY.but burns with a brilliant light', giving a white smoke and a depositof brown silicon. It melts a t -144O and boils a t - 1 5 ' 2 O760 mm., these constants being lower than those of the parentdisilane. This is the reverse of that observed with dimethyl etherand ethane.With water, disiloxane soon reacts to give hydrogen and in-soluble compounds, like (SiH,O),, etc. With sodium hydroxidesolution, the decomposition is complete, according to the equation(SiH,),O + H,O + 4NaOH = 2Na,Si03 + 6H2.Disiloxane reactsvery vigorously with chlorine a t -125O to give hexachlorodi-siloxane, but most of this decompolses according t o the equation4(Si@1,),0 = 2Si0, + 6SiC1,. Tetrachloromonosilane, SiCl,, meltsa t - 68.7O and boils at 13'i0/760 mm., whilst hexachlorodisiloxanemelts a t -33O and boils a t 137O/760 mm.It would appear that protosiloxane, SiH,O, can be obtained bythe action of water on dibromomonosiloxane, but it is very difficultto separate the compound from the hydrogen bromide which isformed a t t*he same time. Furthermore, the substance polymerisesto a white, amorphous solid, (SiH,O),. This polymeride is stablea t 300° in a vacuum, but+ it inflames i n air oir chlorine and reactswith sodium hydroxide according t o the equation (SiH,O), +2NaOH --+ 2H2 + Na2,Si03.Lastly, a very remarkable reaction of the silanes may be notedin that, with hydrogen bromide in the presence of aluminiumbromide they give bromine substitution products.Thus silanegives very readily monobromo- and dibromo-silane according t othe equations SiH, + HBr = SiH,Br + H, and SiH, + 2HBr =SiH2Br2 + 2H2. This method f o r the preparation of the lowerbromides is better than the direct bromination of silane.Some further work on the zirconyl salts mentioned in last year'sReport may be described.23,24~ 25 It appears that the usuallyaccepted normal zirconium nitrate, Zr(NO3),,5H2O, does not exist,for a11 atkempts t'o prepare it by evaporation of solutions ofzirconium hydroxide in nitric acid, even in an atmosphere saturatedwith nitric acid fumes, resulted in the formation of normal zirconylnitrate, ZrO(N03),.with either 2€1,0 or 3.5H2O. When this saltis heated at 120° in the presence of nitric acid vapour, it loseswater and nitric acid, giving the basic nitrate,3ZrO(NO3),,ZrO,,7H,O.By heating the normal zirconyl nitrate in air, the following basic23 E. Chauvenet and Mlle. L. Nicolle, Compf. rend., 1918, 166, 781, 8214., ii, 234. 624 E. Chauvenet and Mlle. H. Gueylard, ibid., 167, 24, 126 ; A., ii, 369321.86 P. Brubre and 33. Chauvenet, ibid., 201 A., ii, 321INORGAN LC CHEMlSTRY. 39salts are formed : 2ZrO(N03),,Zr0,,7H20, ZrO(N03)2,2Zr0,,4H,0,ZrO(N0,),,7Zr02,5H,0, and ZrO(N03),,10Zr02,4H20.Anaqueous solution of the normal zirconyl nitrate slowly under-goes hydrolysis, giving a precipitate having the compositionZrO(N0&,ZrO2,nH2O.Normal zirconyl sulphate forms compounds of the types(ZrOSO,),,X and (ZrOSO,)&,, where X is either ZrO,, Na2S0,,K,SO,, or (NH,),SO,. The following have been isolated:(ZrOSO 1)3,K,S0, ,8H,O, ( ZrOSO,),,Na2S0,,7H20, and(ZrOS0,),,2(NH4),S0,,7H,0.Evidence has also been found f o r t-he existence of the followingdouble salts of acid zirconyl sulphate : 2(ZrOSO,,SO,) ,3Na,SO,,3 (ZrO SO,,SO,) , 2Na,S04, ZrOSO,,SO,,( NH,),SO,, andZrOSO4,S0,,2 (NR,),SO,.The first two salts have also been obtained with 8H20 and 7H,Orespectively.If the tetra-ammonia. derivative of zirconium chloride,ZrC1,,4NH3, is heated a t 350°, it is converted into zirconiumnitride, Zr3N,.The formulze Zr,N, and Zr,N, put forward byearlier workers are incorrect.I n last year’s Report attention was directed to the remarkableanalogy between the new oxychloride of zirconium thereindescribed, Zr,0,C14,22H,0, and the basic chloride of tin,Sn,08C3,,7H,0, and a t the same time stress was laid on thenecessity for systematisation of metastannic acid and its deriv-atives. Some new work on metastannic acid has been publishedwhich bears on this question to a certain extent.26 The presentwork deals with t,he action of nitric acid on tin, and the productsnow reported differ somewhat from those usually believed to occur.I f the nitric acid is diluted with 1.25-2 volumes of water, theonly product is stannous nitrate, and with more concentrated, andeven undiluted, acid at 0-15O, the formation of stannous nitratecan still be observed, accompanied by normal or basic stannicnitrate.Stannic nitrate even a t the ordinary temperature slowly changesto the meta-salt.At 45O, the change is so rapid that the solutionsuddenly gelatinises, and, after prolonged heatiog atl looo, thechange is complete. The powder obtained by the oxidation of tinwith hot nitric acid, commonly called metastannic acid, is really anitrate of metastannic acid, which on prolonged washing withwater gives metastannic acid. The metastannic acid prepared inthis way and dried in the air a t the ordinary temperature has thecompositjon 5H,Sn03,4H,0, the 4H20 being lost on storage over26 A.Kleinschmidt, Monabh., 1918, 39, 149 : A., ii, 40040 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.sulphuric acid in a vacuum for several days. The statement isalso made that parastannic acid, H2Sn5011,2H20,27 is only ordinarymetastannic acid.Metastannic acid reacts with hydrochloric acid and sulphuricacid t o give easily hydrolysable compounds, and the resultingmetastannyl chloride gives with sodium hydroxide the salt,5 Sn02,Na20,4H20. The nitrate of met’astannic acid describedabove has the constitution 5Sn0,,2HNO3,3H,O, whilst metastannylchloride has the formula 5Sn0,,2HC1,3H20.It. is preferable for the purpose of comparison to discuss theresults given in this paper on t”he basis of Engler’s formulz.Thusthe formula of sodium metastannate should be writtenNa,Sn,0,,,4H20,and hence metast.annic acid should be given the formulaH,Sn,0,,,4H20. The air-dried metastannic acid described in theabove paper is therefore H2Sn50,,,813,0, which differs very littlefrom that given by Engler, R,Sn,O,,,SH,O. Kleinschmidtentirely confirms Engler’s results withh sodium metastannate andwith metastannyl chloride, Sn,0,C12,4H20, butl he has apparentlyisolated new salts in metastannyl nitrate, Sn,O,(NO3),,4H2O andmetastannyl sulphate, Sn,09S0,,4H,0.It must be confessed that, in view of the undoubtedly strongevidence brought forward by Engler in favour of the existence ofparastannic acid and its derivatives, Rleinschmidt’s statement thatthe para-acid is merely metastannic acid does not appear convincing.I n the first place, Engler found air-dried metastannic acid to beH,Sn,O,,,SH,O, and air-dried parastannic acid to beboth losing 5H,O 0x1 drying over sulphuric acid in a vacuum.Kleinschmidt finds air-dried metastannic acid to be H2Sn5011,8H30,and possibly, therefore, he did not sufficiently differentiate betweenthe two hydrates.I n the second place, Engler obtained thechlorides and the sodium salts of the two acids and differentiatedbetween them. I n the third place, as pointed out by the writerin lastl year’s Report, there seem to exist two series of basiczirconyl salts with the same relationship between them, as statedby Engler to exist between his metastannic and parastanniccompounds.It has been found possible to prepare the sub-chloride, sub-bromide, and sub-iodide of lead by the action of t,he correspond-ing methyl haloid on lead sub-oxide.28 This oxide is obtained byheating lead oxalate in an exhausted tube atl 270-370°, careH2Sn50i1 ,7H@,-“7 R.C. Engler, Contpt. rend., 1897, 125, 464 ; A,, 1897, ii, 29.z8 R. G. Denham. T., 1917, 111, 29; 1918, 113, 248INORGANIC: CHEMISTRY. 41being taken that the total pressure of the evolved gases does notexceed 5 mm. By the action of methyl iodide vapour a t a maxi-mum temperature of 262O 011 the sub-oxide, lead sub-iodide isobtained as a pure yellow powder. It has a solubility in waterabout one-ninth of that of the normal iodide, and the solutiongives no precipitate witmh potassium chromate and only a slightdarkening with hydrogen sulphide. On heating above 300°, thesub-iodide darkens in colour owing t o decomposition t o lead andlead iodide.By analogous methods, the sub-chloride and sub-bromide of leadhave been prepared as grey powders.Both are sparingly solublein water, fairly stable in air, but easily oxidised by bromine water.Both salts are readily decomposed by acid into the normal saltand lead.Group 7.A method has been described for the preparation of chemicallypure antimony, the commercially pure metal not being satisfactoryin this respect.29 Antimony trichloride or pentachloride ispurified by distillation and convert.ed into chloroantimonic acid .3OThe chloride is dissolved in concentrated hydrochloric acid, andchlorine is passed in until the solution becomes greenish-yellow,and then hydrogen chloride is introduced.After purification byrecrystallisation, t3he chloroantimonic acid is hydrolysed to anti-monic acid, which is reduced to metal by fusion with potassiumcyanide. The metal thus obtained is free from all impurities andmelts a t 630.3O.Met,allic antimony dissolves in a solution of sodium in liquidammonia.3' It would seem that there are a t least two compoundsformed, in one of which the atomic ratio Sb:Na is greater than2:1, whilst in the other itd is less than 2 : 1 . Some electrolyticinvestigations show that the antimony is present in the solutionsas anion, and that more than one atom of antimony is associatedwith each negative charge.hypo-chlorous acid in equivalent proportions in cold aqueous solution,potassium chlorominosulphonate, NHCl-SO,K, is formed .32This salt may be isolated by evaporating the mixture to asmall bulk, in a high vacuum, a t as low a temperature aspossible and precipitating with alcohol.It forms limpid, hygro-aB E. Croschuff, Zeitsch. anorg. Chent., 1918, 103, 164 ; A., ii, 322.30 R. F. Weinlmd and H. Schmid, ibid., 1906, 44, 37 ; A . , 1905, ii, 326.31 E. B. Peck, J . Amer. Chem. Soc., 1918, 40, 335 ; A., ii, 168.52 W. Traube and E. von Drathen, Bw., 1918, 51, 111 ; A., ii, 108.By the interaction of potassium aminosulphonats andc42 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.scopic crystals, and is comparatively stable.When warmed withmineral acids, the salt undergoes hydrolysis according to the equa-tion NHC1*S03K + H,O = NH&l + KHSO,. The correspondingbarium salt is not so stable, but potassium bromoaminosulphonateis very similar in its properties.Group V I .When diantipyryl selenoselenide, R,Se:Se, was burnt in a bombin oxygen under 25-30 a h . pressure, -a white, amorphous depositwas formed adhering firmly to the walls of the crucible. Thisproved t o be a new oxide of selenium approximating to the formulaSe3O,.a The substance is almost, insoluble in water, and is decom-posed by boiling sodium hydroxide, about one-third of the seleniumbeing deposited in the elementary state, the remainder giving riseto sodium salts of selenium acids.Ferrous selenate can readily be obtained by the action of aconcentrated solution of selenic acid on ferrous sulphide.34 Acertain amount of the selenic acid is reduced by the hydrogensulphide in accordance with the equation 3H,S + H,Se04 = Se +3S+4H20, but this does not interfere with the application of themethod.If the filtered solution is allowed to crystallise, maneclinic crystals of FeSe0,,7H20, isomorphous with FeSO4,7H,O, areobtained. The double seleiiates of the type M,Se0,,FeSe0,,6H20are readily obtained in the case of ammonium, rubidium, andmsium. The corresponding potassium salt crystallised a t atemperature not much higher than Oo, whilst a t the ordinarytemperature very small, monoclinic crystals of the dihydrated saltare formed.Reference was made in last year's Report to the action ofchromyl chloride on phosphorus trichloride or phosphorus tri-bromide in dry carbon terachloride solution, by which compoundsof the type CrOCl,POCl, are formed.This work has now beenextended to include a study of the action of chrmyl chloride onphosphorus di-iodide, tri-iodide, pbtachloride, and pentabromide.35I n t h e case of the first three phosphorus haloids, simple additivecompounds are precipitated ' containing one molecule of chromylchloride and one molecule of the phosphorus haloid. No reactionsimilar to that occurring with phosphorus trichloride and phos-phorus tribromide takes place. In the case of phosphorus penta-F. von Konek, Ber., 1918, 51, 872 ; A., ii, 309.A.E. H. Tutton, Proc. Roy. SOC., 1918, [A], M, 362 ; A., ii, 193.35 H. S. Fry and J. L. Donnelly, J . Amer. Ohem. SOC., 1918, 40, 418 ; A.,ii, 167INORGANIC CB EMISTRY. 43bromide, no definite compound was formed, but a mixtlire, pre-sumably of Cr02C12,PBr, and CrOCl,POBi-~,, due, no doubt, to thepartial dissociation of the phosphorus pentabromide in carbontetrachloride solution.The compound, Cr0,C1,,P12, is brown and very unst'able in moistair. It is readily decomposed by water with liberation of iodine,and, after boiling, the solution contains phosphate, chromate,chloride, and iodide ions.The compound, CrO,Cl,,PI,, f ornis a purplish-red powder whichreacts with water in accordance with the equatJon 2CkO2CI,,PI3+4H,O = 4HCl+ 4HI + 2CrP0, + I,, and the compound,is a yellowish-red powder which readily decomposes in the air,evolving hydrogen chloride.Considerable interest attaches to the preparation of a series ofcompounds of quinquevalent tutgsten.36 The starting point is thereduction of tungstic acid or a tungst-ate in oxalic acid solutionwith tin.The best results are obtained by reducing a solution ofan alkali tungstate in a concentrated solution of oxalic acid con-taining slight excess of alkali oxalate. The course of the reduc-tion can be followed by the colour change, through dark blue,green, and yellow to deep red. After removal of the tin andexcess of oxalic acid, the complex oxalotungstite is precipitated bymeans of alcohol, aiid may be purified by dissolving in hot waterand salting out, the sodium salt 1vit.h sodium bromide and thepotassium salt with potassium iodide.The salts must be dried ina current of carbon dioxide, but are fairly stable in air when dry.The sodium salt, 3Na,0,2W,0,,4C'20,,12H20, and the potassiumsalt, 3K,0,2W20,,4C,O3,9H,0, form red, crystalline powders whichslowly oxidise in the air, and a t looo lose their water of crystal-lisation, but do not decompose. They are very readily soluble inwater, but are insoluble in organic solvents.The oxalotungstites dissolve in concentrated hydrochloric acid,forming a deep blue solution, which contains an oxychloride ofquinquevalent tungsten, probably WOCl,, because from this solu-tion complex chlorides can be isolated containing WOCl, in com-bination with chlorides of the alkali metals or ammonium or hydro-chlorides of organic bases.The ammonium and potassium saltsare precipitated by saturating a hydrochloric acid solution of thecorresponding oxalotungstite with hydrogen chloride. Therubidium, czesium, aniline, tet rae t hyl- and tetraprop yl-ammoniumcompounds are precipitated when the corresponding chloride isadded to a hydrochloric acid solution of an oxalotungstite. and the36 0. 0. Collenburg, Zeitsch. anorg. Chem., 1918, 102, 247 ; A,, ii, 267.fiO,Cl,,PC1, 9c* 44 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.pyridine and quinoline compounds are prepared by double deconiposition of their hydrochlorides with ammonium chlorolt'ungstite .Four types of these complex chlorides have been observed.TypeIa has the composition M,WOCl,, in which M may be NH,, Rb,Cs, or C,H,NH,; type I b , M,WOCl,,zH20, is represented by thepotassium compound; type IIa, MWOCl,, is represented by thepyridine and quinoline compounds ; and type I I b , MWOCl,,H,O,by tetraethyl- and tetrapropyl-ammonium compounds. The com-pounds of type I form green crystals and correspond with themolybdenyl chlorides. The compounds of type I1 have no repre-sentative among molybdenum compounds ; they form shining,brown crystals (IIa) or bright? greenish-blue crystals ( I I b ) .The chlorotungst<ites are stable in dry air a t the ordinarytemperature, but. decompose with oxidat<ion to tungstates at60-70°. They are inmediately hydrolysed by water with form-ation of a brown hydroxide, which has not been malysed.Theydissolve readily in absolute methyl or ethyl alcohol, with theexception of the rubidium and caesium compounds, but not inother organic solvents. Concentrated hydrochloric acid and 35 percent. sulphuric acid also dissolve them, but alkalis and ammoniadecompose them.The chlorotungstites react vigorously wibh a concentrated solu-tion of potassium cyanide, with evolution of hydrogen cyanide. Areddish-yellow solution is formed containing cyanides of the typeM,w(CN),, from which a sparingly soluble cadmium compound,Cd2W(CN),,8H,O, has been isolated. A thiocyanic acid compoundhas also been isolated in the form of a pyridine salt having thecomposition (PyH),WO( SCN)5,sHz0.Reference may be made to the important work on the natureand constitution of the heteropolytungstates and the hetero-polymolybdates.The complexity of these compounds is a t firstsight somewhat confusing, but some fresh light has been thrownon them which has enabled them very definitely to be classified.37The nomenclature of these acids and their salts is based on theratio between the numbers of the atoms of the non-metallic elementand the metallic element (tungsten or molybdenum) in tqhe com-plex anion. The fundament'al type of the mononuclear acids isthe 12-type with the general formula HI2 - ,[Rn(M207)6], where Ris the non-metallic element of valency n and M is the metallicelement. This type is the most stable of all these acids, and isformed in the presence of excess of the metallic acid.These acidsform two series of hydrates, one of which crystallises in quadratic37 A. Rosenheim and J. Jiinicke, Zitsch. anorg. Chem., 1917, 101, 236A., ii, 77INORGANIC CHEMISTRY. 45octahedra with 28H,O, and the other in rhombohedra with 22H20.The following have been prepared:12-Borotungstic acid, H9[B(W2O7),],28H,O, forms two kinds ofcrystals, namely, large, transparent. octlahedra melting a t 45-51',and slender needles. A lower hydrate with lOH,O was isolated.An iso-12-borotungstic acid, Hg[B(W20,),] ,22HB0, was obtained inthe form of hexagonal, bipyramidal crystals.1 2-Silicomolybdic acid, H,[Si(Mo,0,),],28H20, forms trans-parent octahedra, which melt gradually a t 47-55O t o a uniformliquid.When crystallised from hot nitric acid, it forms a lowerhydrate with 14H20.12-Silicotungstic acid crystallisev with 28H,O and with 22H20,the transition point being a t 28.5'.12-Phosphomolybdic acid exists in yellow, octahedral crystals ofthe constitution H7[P(Mo207),],28H,0, and by crystallisation f r mhot nitric acid it is obtained in small, yellow, probably rhomho-hedral, tables with 22H20.12-Phosphotungstic acid forms crystals of the normal type with28H,O which, in the presence of traces of acid, break down intominute rhombohedra with 22H,O. The highest metallic saltswhich could be prepared of tshis acid were tribasic, for example,Na,H4[P(W20,),],13H,0, 'but in the guanidine salt,half the hydrogen is replaced.12-Arsenotungstic acid could only be obtained in the form ofits ammonium salt, (NR4),H4[As(W,O7),1,4H2O.I n addition to the above, unsaturated mononuclear acids havebeen prepared of the type HI, - n[RnO(M207),], their basicity beingthe same as that of the.saturated acids.10-Silicotungstic acid was obtained in the form of a potassiumsalt as cube-like crystals of the composition(CN,H,)H7[P(W.207),1,,12H,O,K7H[SiO( W207)5], 1 1H20.Turning to the biiiuclear acids, these form two groups, the 1 : 11acids having an outer bridge,and the 1 : 9 (Iuteo-) acids an inner bridge,The acids of the last type, it is suggested, are in tautomeric equil-ibrium with the formH7[ Rn OH* ( M207) 5] M207 * [Re 12 OH - (M,07 ) ,]H 7,HI,- n[(M2,07)4Rn0*M20,*R"0'(Mz07)4]H,, - n -Hi, - n[(M20;r)4RnOH.M207*RnOH(Ms07)*]H,,-11-Phosphotungstates are formed at an intermediate stage inthe decomposition of 1 2-phosphotungstic acid by strong bases46 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTKY.They are stable salts which can be readily prepared from thebarium salt, to which the constitutionis given.The 1 l-arsenot'ungstates are completely analogous to thephosphotungstates.9-Phosphotungstic acid, P20,,18\/V0,,42H2,0, forms thin, six-sided tables, which are very readily soluble and melt a t 2 8 O . Sinceall attempts to prepare salts of higher basicity than 5 failed, i twas concluded that the constitution of this acid must be i-epre-sented by t'he formulaH,[P(OH)(W,O,),* \V207*(\V20,)4(OH)B]HS;36H20.Ba,[P(OH)(W20,),l*W,0,*lI(W,O,),(OH)P],53~z0The silver salt, 5Ag20,P,0,,18W0,,34H,0, is precipitated asyellow, amorphous flakes, which quickly crystallise.9-Arsenotungstic acid corresponds exactly with the 9-phospho-tungstic acid.Only the tribasic potassium and ammonium saltswere prepared, these having similer properties to the tribasic saltsof the phosphotungstic acids.Still inore complex heteropoly-acids have been studied whichprobably contain four nuclei, but no coiistitutional formulze haveas yet been suggested for them.Group PIXI.Some years ago, an account was published of the preparationand properties of the nitrosopentamminecobalt salts .38 Two seriesof salts were described, one being red and the other black. Bothseries were obtained by the actmion of nitric, oxide on ammoniacalsolutions of cobalt salts and have the same general formula,NO*@o(NH,),*X,, the two series being considered to be valencyisomerides. This work has been repeated, and it is now claimedthat whilst the earlier statements witli respect to the black seriesare correct, most of the statements with respect t o the red seriesare incorrect .39These salts present considerable interest from the point of viewof valency and also from the point of view of their constituticn.Whereas the black series has the simpleabove, the red series must be consideredformula8 8 J. Sand and 0. Genssler, Ber., 1903,36, 2083 ;a9 A. Werner and P. Karrer, Helv. Chim. Acta,1903, 329, 194; A., 1904, ii, 39.constitution as statedas having the generalA , , 1903, ii, 549 ; Annalen,1918, 1, 54 ; A,, ii, 319INORGANIC CHEMISTRY. 47and the question of the nature of the radicle, N,O, is as yet un-decided. By the action of acids, the radicle is split off as hypo-nitrous acid, HzNz02, which, however, immediately decomposes,giving nitrous oxide. It was not found possible to isolate thehyponitrous acid or to detect i t in solution. Attempts were madeto prepare the red salts by the action of silver hyponitrite onchloropent.amminecobalt salts, but they were unsuccessful, aquo-pentamminecobalt salts being obt'ained.Some of the new salts now described may be noted.Black nitrosopentamminecobalt iodate, NO*CO(NH~)~(I.O~)~, isprecipitated as a blackish-brown, crystalline powder when nitricoxide is passed into a strongly ammoniacal solution of cobalt iodate.Dinitrosodecamminedicobalt salts (red series), YX,, whereY = N,Oz*C~(NH,),,. The following members of this series maybe mentioned : YBr4,3H,0, Y14,4H,0, Y(S04),,2H20, Y(C,O,),,H,O,Y(Cr0,),,4€IT0; in addition to these, several acid salts have beenobtained. Many of the red salts described by the earlier authorsare now stated not t o exist.Definite compounds have been prepared of mmium tetroxide withthe hydroxides of potassium, rubidium, and msium, and in thisway the tetroxide is proved to possess an acid function.40 Thepotassium compound, Os0,,2KOH, the rubidium compound,OsO,,RbOH, and the two casium compounds, OsO,,CsOH and20s04,CsOH, all form orange o r brown crystals, and are readilysoluble in water, in which solution they are strongly hydrolysed.Mention may also be made of the fact that osmium tetroxide isreduced by concentrated hydrochloric acid according to the equa-tion 2 0 ~ 0 , + 12HC1= 2OsO + 6C12 + 6H20.41E. C. C. BALY.4 0 L. A. Tschugaev, Compt. rend., 1918,167, 162 ; A., ii, 322.41 J. Milbauer, J. pr. Chem., 1917, [ii], 96, 187 ; A., ii, 202

ISSN:0365-6217    

DOI:10.1039/AR9181500026

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

ORGANIC CHEMISTRY.PART I.-AL I PHAT I c D I VI s I ON.IT is not improbable that the Annual Reports are subjected to inorecriticism than the publications out of which they are constructed,but possibly on the present occasion sympathy will be accordedboth to the reviewers and t o those who, during an exceptional year,have striven to preserve theoretical and disinterested research. Dueappreciation of research demands full recognition of the conditions,material and otherwise, under which the work is done, and comequently one ought not to labour the obvious and condemn theprogress recently made in aliphatic chemistry as trivial. Muchoriginal ibility has, of necessity, been directed into other channels,so that publicatioiis have been reduced both in number and quality,but there is no reason why this should be regarded as a symptomof intellectual famine.On the contrary, there are many signs,amongst which may be included the advent of new periodicals,that research work is entering on a wider and more active phase.I n compiling this section of the present Report, an attempt hasbeen made t o preserve the form adopted in recent years, and tomake the narrative continuous. I n some cases it has been difficultto resist the temptation of trying to make a modest ration go as faras possible so as to avoid the appearance of dealing preferentiallywith favourite topics, hub although the different branches of thesubject are treated iu varying detail, the space allocated to eachheading is roughly proportioiial to the amount and standard of thework to be discussed.Throughout the year the writer has been encouraged in his taskby the hope that the Report would be studied by those who werereturning with fresh zeal t o interrupted scientific work.I f thishope is realised, such reasders are unlikely to be critical, and thewriter will be amply rewaided.l'iydr ocar b o ns.The most outstanding publications on aliphatic hydrocarbonswhich have appeared during the period embraced within the current4ORGANlC CHEMISTRY. 49Report are coiiceriied with the effects of temperature and pressureon the limits of inflammability of air-methane mixtures. Thenature and treatment of this important topic place the work beyondthe scope of the present section, but the latest contributions 1s 2* 3 tothis systematic series of researches should not remain unnoticed.Inrecent years much of the synthetical and descriptive work on open-chain hydrocarbons has emanated from Russia, and in default ofcontinued publications from this source, there is comparatively littleto report under the above heading. It is, in fact, mainly with theidea of preserving the subdivision adopted in previous Reports thata separate section is now devoted to 'hydrocarbons.Mention should be made of the synthesis of tertiary hydro-carbons,4 which has been commenced by Levene as a preliminary tothe study of the oxidation of these compounds. "he methodsemployed are for the most part orthodox. Thus, in the particularsynthesis which has been carried t o a completion a start was madefrom ethyl dibutylmalonate, C(C,H,),(CO,Et),, from which a-butyl-liexoic acid, CH(C,H,),*CO,H, was obtained in the usual way. Fromthis, the corresponding ethyl ester was prepared and reduced to givea-butylhexyl alcohol.Subsequent conversion into the correspondingiodide, followed by reduction with zinc and acetic acid, ultimatelyyielded B-butylhexane. The essential steps are outlined below :C(C,H,),(CO,Et), + CH(C,H,)g*CO,H +CH(C,H,),*CO,Et -+ CH(C,H,),*CH,*OH -+The most importanC experimental feature of the above syntheticalscheme is the reduction of tile ester t o the corresponding alcohol,this process having been effected by means of sodium.Although the ultimate objective in an important paper, t o whichatt'ention is now directed, was the accumulation of evidence bearingon the technical refining of petroleum oils, a number of usefulgeneralisations have been made on the action of sulphuric acid onole fine^.^ On the resu1t.s of a large number of comparative tests, itis shown that the formation both of alcohols and of alkyl sulphatesis profoundly affected by the electrocheinical character of the sub-stituting groiips introduced iiito tile parent ethylene molecule.Another generalisation which emerges is that polymerisation ofCH(C,H,),-CH21-+ CH(C4H,),*CH,.W.Maeon and R. V. Wheeler, T., 1918, 113, 45.W. Payman and R. V. Wheeler, ibid., 656.R. V. Wheeler, ibid., 840. ' P. A. Levene and 1;. H . Cretcher, jun., J . Biol. Ohm., 1918, 33, 505;B.T. Brooks, and I. Humphrey, J. Amer. Ghem. Soc., 1918, 40, 822 ;A., i, 260.A., i, 28650 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ethylenic hydrocarbons by the agency of sulphuric acid becomesmore pronounced as the molecular weight of the olefine increases.It is pointed out in view of this observation that the identificationof plynaphthenes in hydrocarbons which have been purified bytreatment with sulphuric acid is not conclusive evidence of the exist-ence of these compounds in the original petroleums. The investiga-tion now under review also includes an examination of the condi-tions under which alcohols are formed directly by the action ofdiluted sulphuric acid on ethylene, and the work is stamped ascommendable in that a difficult technical problem has been attackedby systematic, if laborious, methods, giving results of very generalinterest.A brief reference may be introduced here to a few new observa-tions concerning compounds closely related to simple hydrocarbons.The fact that the reaction between carbon tetrabromide and silverfluoride takes place in definite stages to give the complete series ofintermediate fluorobromo-derivatives is only noteworthy in view ofthe drastic conditions necessary to complete the fluorination.6 Thisdifficulty will not come as a surprise to those who have had frequentoccasion to displace one halogen by another even in aliphatic com-pounds of the simplest type.Then again, as halogen compoundsare frequently used as solvents in exact measurements, it may benoted that chloroform is comparatively unstable under the influenceof ultra-violet radiation,' and, further, that trichloroethylene is onoccasions a somewhat fickle solvent, on account of its tendency todisengage hydrogen chlolride.s It is well to recognise these proper-ties before entrusting to the solvents valuable material which iseasily hydrolysed by traces of acids.Practical details have also been contributed 9 of a variation inthe preparation of chloroform from alcohol, and these should findapplication in the teaching laboratory, and thus introduce economyinto a preparation which, in the hands of elementary students, isnotoriously wasteful.Practically all the publications on aliphatic alcohols have bee11concerned with pyrogenic changes, or with the reactions whichhydwxyl cornpounds undergo a t moderate temperatures in the pres-ence of catalysts.Taking the particular case of ethyl alcohol, itH. Rathsburg, Ber., 1918, 51, 669 ; A., i, 333.A. KcLilan, Monatsh., 1917, 38, 637 ; A., i, 209.W. Elsner, Chern. Zeit., 1917, 41, 901 ; A., i, 210.K. Ukita, J . Cham. Ind., Tokyo, 1918, 21, 219 ; A., i, 333ORGANIC CHEMISTRY. 51ia, of course, well known that the decompwition promoted by theagency of metals or of metallic oxides may follow two alternativeroutes, leading respectively to (a) ethylene and water, or ( b ) acet-aldehyde and hydrogen. Determination of the ratio C2H, : H2 inthe evolved gases thus gives an index of the partition betweenthese two rival reactions.In a study 10 of the relative effects of various catalysts on alcoholsi t is shown that, as was to be expected, the presence of water vapouris favourable to the formation of acetaldehyde, and, conversely, that,the addition of hydrogen t o the gaseous alcohol increases the pro-portion of ethylene.That the offect ofi water vapour is a seriousfactor in these reactions is also1 indicated by the results obtained ina daring attempt to examine the products formed when glycerol issubjected to various types of catalytic decomposition .11 Consideringthe possibilities which are open, however, the products actually iso-lated are surprisingly simple. Thus the effect of passing glycerolvapour over heated alumina is t o produce acraldehyde, whilst, inthe presence of finely divided copper, ethyl and ally1 alcohols arelormed.With uranous oxide, on the other hand, both the abovealcohols are produced, t'ogether with some acraldehyde, and the com-bined results furnish a good example of the application of catalyticprocesses to compounds of great reactivity without. encountering thecomplete molecular breakdown which might reasoiiably have beenpredicted.Although it is well known that the action of phosphorus haloidson polyhydroxy-compounds is extremely complex, the fact thatsimple monohydric alcohols frequently. react abnormally is not sogenerally recognised. I n the course, however, of examining theformation and reactions of alkyl phosphites, new facts have comet o light which serve to clear up a number of difficulties.Whenphosphorous chloride acts on an alcohol, the reactions which ensueinvolve the successive formation and decomposition of the completeseries of alkyl phosphites.12 The three consecutive reactions aret.hus Pa3 + 3R.OH = P(OR), + 3HC1+ OH*P(OR),+ RC1-OR*P(OH), + RC1+ P(OH), + RC1, and, according to the experi-mental conditions, the reaction may be approximately arrested a tany desired stage. I n an extension 13 of the work a detailed accountis given of the stability of dialkyl phosphites. These cumpunds, aswas to be expected, are found to be neutral towards indicators andlo C. J. Engelder, J . PAgsieal Chem., 1917, 21, 676; A., ii, 13.l1 P. Sabatier and G. Gaudion, Corn@. r e d . , 1918,166, 1033 ; A,, i, 334.12T.Milobendzki and A. Sachnoweki, Ohernik PObki, 1917, 15, 34; A.,18 Ibid., 48 ; A., i, 478.i, 477are poor conductors, but nevertheless are capable of formingmetallic salts by somewhat indirect methods.14d Idehydes and Ketones.Although good working methods are available fox preparing thelower aliphatic aldehydes, practical difficulties. quickly intervenewhich place limitations on processes depending on the catalyticdehydrogenation of alcohols, and the synthetic organic chemist willwelcome a new method15 in which aldehydes can be convenientlyprepared from the corresponding acyl chlorides. The reduction iscarried out catalytically, a stream of hydrogen being passed througha boiling solution of the chloride in an indifferent solvent, such asxylene.These energetic conditions do not seem to affect the cata-lyst, which may be either barium sulphate coated with palladiumor the particular form of nickel recommended by Kelber. Experi-mental details are quoted which lead to the opinion that the processpossesses a high degree of efficiency. The fact that butaldehydehas in this way been obtained in 50 per cent. yield from butyrylchloride is perhaps not in itself a specially striking example of itsmerits, but the method can evidently be applied successfully to thepreparation of aromatic hydroxy-aldehydes,lG and there seems noreason why it should not be equally applicable to the production ofsubstituted aldehydes of the aliphatic series.Far a considerable time the hope has been entertained that acet-aldehyde may prove t o be a starting point in the preparation ofmany compounds of varied type, and, naturally enough, attentionis still being directed to improving the methods of obtaining thocompound from acetylene.17 Some indication of the pteniial valueof acetaldehyde is given in a paper18 which describes its catalyticconversion into crotonaldehyde by the action of uranium oxide a t360O.The product can thereafter be easily reduced by means ofnickel to give n-butyl alcohol, and the further fact emerges that,during the crotonisation of acetaldehyde, a certain amount of higherliomologues is formed. This observation a t once opens out widepossibilities.With regard t o ketones, few points of general interest have beennoted, but reference should be made ta two papers dealing with the1*T.Miiobendzki and M. Szwejkowska, Chemik Polski, 1917, 16, 66;A., i, 479.l6 K. W. Rosenmund, Ber., 1918, 51, 585 ; A., i, 300.16 K. W. Rosenmund and F. Zetzsohe, ibid., 694 ; A., i, 300.l7 H. Dreyfus, Brit. Pat., 105064 ; A,, i, 261.I s P. Sabatier and G. Gaudion, Compt. rend., 1918, 166, 632 ; A , , i, 251ORG A N J C CH EM TSTRY . 53chemistry of acetone, which, in view of existing conditions, ought,iiot t o remain unmentioned. Although the production of acetoneby the dry distillation of calcium acetate is now a process whichhas been brought to a remarkable state of efficiency, the reactionsinvolved are complex and the by-products are numerous. I n parti-cular, the formation of gases represents a serious loss of acetone,and information indicating the conditions under which theseby-products are produced is somewhat scanty.It has been shown,however,19 that when acetone is heated with lime at temperaturesranging u p to 630°, a species of “cracking” occurs, which resultsin the formation of methane, ethylene, hydrogen, carbon monoxide,and carbon dioxide. As the temperature is raised t o the upperlimit mentioned, t-he amount of methane increases rapidly, whilstthat of hydrogen is diminished. The explanation put forwardis that acetone undergoes (a) a high temperature dissociation, and( b ) conversion into keten, which thereafter decomposes :CH,*CO*CH, --+ CH, + CO + G + H,.CR,*CO-CH, -+ CH, + CH,:CO.2CHZ:CO + 2CO + CZH,.This scheme can be expanded Lo account fairly well for the knownprducfkl which accompany acetone during manufacture by the drydistillation method, particularly when the influence of metals inpromoting further catalytic changes is taken into account.Theexperimental conditions adopted in the research now under discus-sion are, moreover, those which are liable to be reproduced in large-scale working. It is obviously a difficult problem t o minimise theproduction of gas in the manufacture of acetone, but evidently theexclusion of air and the limitation of the temperature t o the lowestworking minilriuni during dry distillation are essential factors.As the standard tests for the purity of acetone depend on theuse of alkaline potassium permanganate, interest is attached to apaper which deals with the mechanism of the reactions involved20It has long been known that, in the absence of alkali, pure acetoneis not appreciably attacked by permanganate, and it now appearsthat the oxidation of the ketone in an alkaline system follo’ws adifferent route according to the amount of alkali added.I n order toaccount for the fact that the essential oxidation products are aceticand oxnlic acids together with carbon dioxide, it is suggested thatl9 M. E. Freudenheim, J . Physical Chem., 1918,22, 184 : A., i, 252.20 E. J. Witzemann, J . Amer. Chem. Soc., 1917, 39, 2657 ; A,, i, 58t,he oxidation process involves preliminary enolieation of the acebrie.followed by the formation of pyruvic acid:COMe, -+ CH,:CMe*OH + HO*CH,*CMe(OH), +CHO*CMe(OH), + C0,HrnCMe(OH)2 +CB,*CO,H + CO,/+CH,*CO*CO,HCH,:C(OH)*CO,H + C,O,H, + CO,.\+The above scheme is in agreement with the general observation thatthe ketones which are attacked most readily by permanganate arethose which are most liable to assume the enolic condition and togive dibasic acids on oxidation. The paper is one which will beread with interest by all who are concerned with the examinationand testing of acetone.Results which may ultimately prove of considerable value in syn-thesis have been obtained in a study of the reaction between mesityloxide and hypochlorous acid.21 On general grounds it might havebeen expected that phorone derivatives would be formed, but thesimple ketochlorohydrin, OH*CMe,*CHCl*COMe, proved to be theessential product.Under the influence of dehydrating agents thispasses into the unsakuratd chlora-ketone, which in turn can betransformed into the corresponding substituted ethylene oxide :Clllf?, CMe,:CCi*COl\de 4 O< I CH*COMeA number of synthetic possibilities are thus opened out; but it willbe well to delay speculation regarding the future of this reactionuntil evidence is available confirming the above formulae.Acids a-nd their Derivatives.Current researches on acids show a tendency to focus on problemsof constitution, and it is well that this should be the case, consider-ing the suspicion with which the standard representation of thecarboxyl group is now regarded.Before referring to a fresh dis-cussion on this subject contributed by Hantzsch, it may be advisableto mention briefly an introductory paper22 which deals with somegeneral principleer.A review of past work on the optical absorption method of deter-mining keto-enol equilibria shows that the results are but little21 K. Slawideki, Chenaik: Polski, 1917,15, 106 ; A., i, 481.88 A. Hantzech, Ber., 1917,50, 1413 ; A., ii, 2ORGANJC CHEMISTRY. 55affected by the formation of additive compuunds between thesolvent and the solute, provided such addition does not occasionprofound structural changes. Several examples are quoted insupport of this view, for which an approximate parallel can fre-quently be found in the analogous phenomenon of optical activity.With regard to the special case of acids, it is pointed out that theethereal salts of a fatty acid show identical optical absorption, andthe same liolds true for the alkali and alkaline earth-salts.In theparticular example of trichloroacetic acid,2S it is interesting to notethat when dissolved in such diverse solvents as water and lightpetroleum, the optical properties of the compound remain constantand are identical with those of the alkali salts in aqueous solution.On the other hand, different absorption curves are given by alco-holic solutions of the acid, but here again these results are dupli-cated by solutions of the esters in indifferent solvents. A commonexpression must thus be found for the salts and for the free acid,and this, according to Hantzsch, is given by the following structuresin which the ionisable fractions are represented as attached to twooxygen atoms:Acid. Salt.R*C<g 1- HAccepting the above view, the conventional expressions R-CO*OBand R*CO*OM are1 resewed for " pseudo-acids " and " pseudo-salts "respectively.It would be inadvisable a t this stage to express anopinion on the above suggestions or t o subject them to detailedcriticism. Some difficulty has evidently been experienced in ex-tending the principles tol examples other than that of trichloroaceticacid, and the experimental results do not agree uniformly with thetheory which, it may be remarked, is a t variance with the results ofother and no: less comprehensive work on 6he structure of aliphaticesters and acids.Considerable interest is attached to the systematic efforts nowbeing made by Boeseken and his pupils to extend the conductivitymethod of ascedaining the constitution and configuration ofhydroxy-compounds to the special case of substituted acids.meprinciple involved is that the addition of boric acid results in pro-nounced exaltation of the conductivity only when hydroxyl groupsare attached t o adjacent carbon atoms and lie on the same side ofthe plane of the carbon chain. Results are now described 2 4 ~ 2 5 whichas A. Hantzsch,Ber., 1917, 50, 1422 ; A., ii, 4.$1 J. B6eseken and H. Kalshoven, Rec. trau. chim., 1918, 37, 130; A,,*& J. Bueseken and pupils, ibid., 165 ; A., ii, 146.ii, 14656 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY-sliow that the method, which was first developed in the sugargroup, is well adapted to the determination of the structure ofaliphatic hydroxy-acids, although, naturally enough, it does notserve to discriminate between a simple racemic acid and its activecomponents .26The extended use to which oxalyl chloride has recently been puthas resulted in the development of yet another method for prepar-ing anhydrides.27 So far, tho process has been applied only t oaromatic examples, but there seems no reason why it should not beequally applicable t o aliphatic compounds.Apparently the reac-tion, which is conducted on the free acid, proceeds in the two stagesshown below:2R*C02H + C2O,Cl2 + 2HC1+ (R-CO O),C,O,.(R*CO*O),C20,- (R*CO),O + CO + CO,.The procedure is simple and the yields obtained are good. I nspecial cases the intermediate mixed anhydride figured above can beisolated as an individual compound, and the reaction thus closelyresembles the thionyl chloride method of preparing anhydrides,and may on occasions prove a convenient alternative.Zsters.A large proportion of recent papers dealing with aliphatic estersis concerned with comparatively unimportant variations in work-ing processes.I n a few cases, however, publications which displayno essential novelty are worthy of meation in view of the utility ofthe results described. All workers who have had occasion t o prepareesters in a specially pure condition must have been struck with thevariable " constants " quoted in the literature, and have been facedwith the difficulty of recognising when any particular preparationconformed to the maximum st.andard of purity. Value is thusattached to a renewed effort28 to determine the exact physical con-stants of a series of simple aliphatic esters.The data now quotedwill be found useful for reference purposes, and it is to be hopedthat the examination will be extended to a larger selection ofcases.Although methyl sulphate has been in use as an alkylatingreagent for a considerable time, the exact mechanism of itsa6 J. Blieseken and L. A. van der Ent., Rec. tmv. chim., 1918,37, 179 ; A . ,ii, 147.27 R. Adams, W. V. Wirth, and H. E. French, J . Amer. Chem. SOC., 1918,40, 424 ; A,, i, 166.ae J.H. Mathews and K. E. Faville, J . Phy8icaZ Chem., 1918, 22, 1 ; A.,153ORGANIC CHEMISTRY. 57hhaviour has been studied only within the past year or two, andeven now is imperfectly understood. As a result it is occasionallysomewhat difficult to predict exactly the best conditions under whichthe reagent should be used. Some light is thrown on this questionby the results of an interesting research,29 in which it has beenshown that, in the methylation of phenolic hydroxyl groups, theuse of potassium hydroxide is inferior t o that of sodium hydroxide,whereas, in ester formation, the best yields are obtained when potass-iuni salts are used. The discrepancy is apparently due t o the moreproaounced hydrolytic effect of potassium hydroxide on dissolvedmethyl sulphate, and this reaction appears t o be catalysed positivelyby potassium salts and negatively by sodium salts.This view hasbeen indirectly supported by the results of an independent investi-gation,30 in which the hydrolysis of methyl and ethyl sulphates inwater and in dilute alkali is compared. I n aqueous solution methylsulphate is hydrolysed much more rapidly than the ethyl compound,and the difference in stability becomes greatly magnified in thepresence of dilute potassium hydroxide. The possibility that thisresult is attributable t o the unequal solubility of the two sulphatesis excluded, and the conclusion is drawn that it is to be ascribedto the different mechanism of the reactions involved. In the paperreferred to, i t is noted as abnormal that whereas sodium meth-oxide reacts with methyl sulphate more readily than with ethylsulphate, a methyl-alcoholic solution of sodium methoxide is lessreactive towards methyl sulphate than an ethyl-alcoholic solutionof sodium ethoside. This observation does not stand alone, but itmay be remarked that reactions invoilviiig metallic alkyloxides,alcohols, and esters are always complicated by 8ri interchange ofgroups between the dissolved ester and the solvent, and the com-parison instituted above has t<hus lit.tle sigilificance.Turning to problems connected with structuure, it is evident thatdiscussion of the keto-end or aldehydo-enol isomerism of esters isby no means closed.I n the case of the ethyl formylphenylacetates,some progress has been made in characterising the solid form (m.p.1 1 0 O ) as the pure enolic variety. On tqhe other hand, it is shownby means of titration by Meyer's method that the liquid isomericlecontains after distillation about 9 per cent. of the aldehydic taut'o-meride.31 Considering the fact that traces of alkali depress themelting points of the formylphenylacet3ates t o a remarkable extent,its is difficult to attach much import'ance to the claim that the liquidand solid modifications of t,he enolic form are distinct chemicalz9 A. KIemenc [with E. Edhofer], Monatsh., 1918, 38, 553 ; A . , i, 220.30 J. Pollak and A. Barn, ibid., 601 ; A., ii, 161.31 W. Dieckmann, Ber., 1917,50, 1376 ; A., i, 16‘’ ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY-individuals.Incidentally, it may be mentioned that the mixtu1-eof isomeric ethyl formylphenylacetates has been utilised in asynthesis of tropic acid,32 the reduction being effected in neutralsolution by the action of aluminium amalgam.It would appear that a systematic effort33 is now being made torevive the study of tautomeric change in esters by means of opticalmethods, special attention being paid ta the variations in specificrefraction and dispersion which accompany keto-enol transform-ation. These factors are selected in preference to molecularrefractions, and the results confirm the idea that not only can thesimple structures *CO*CHR* and *C(OH) :CR* be definitelyidentified, but their relative proportions in mixtures may be estim-ated.In certain cases, however, the results are not so easily inter-preted, as, for example, when a B-diketone undergoes tautomericrearrangement. The two forms thus produced contain, re-spectively, the groupings *CO*CHR-COR’ and OH*C:CR*CR’:O.and the presence of conjugation in the di-enol results in pronouncedexaltation both in refraction and dispersion. This necessitates thestandardisation of optical values in compounds containing typicalconjugated systems, and the experimental determination of thesereference factors is already well advanced. This revival andextension of Briihl’s original proposals seems necessary in biew ofthe stleady accumulat%ion of conflicting and contradictory resultsin the examination of desmotropic changes.One useful applica-tion can already be recorded.34 I n last year’s Report, an accountwas given of new views regarding the structure of the compoundhitherto known as “ ethyl diacetylmalonate,” which has beenshown to be, in reality, the normal acetate of enolic ethyl mono-acetylmalonate. This raises the question if any authentic diacyl-nialonic esters exist, and in the particular case of the “dioxalo-malonates,” the compounds have been subjected to the optical test.The abnormally high values of the refraction and dispersion arefound to be in better agreement with the view that in these ex-amples, also, the compounds are enolic and not true diacylderivatives.Somewhat novel views regarding the structure of the succinyl-malonic esters are expressed in a paper36 which deals primarilywith the corresponding phthalyl compounds.The alternativef ormulz for ethyl phthalylmalonate,yaH,* 7: C(C0,E t)zco---032 E. Miiller, Ber., 1918, 41, 262 ; A., i, 223.3) K. von Auwem, Anmalea, 1918,415, 169 ; A., ii, 381.34 K. von Auwers and E. Auffenberg, Rer., 1918, 51, 1087 ; A., i, 479.M I W . , 1106 ; A., i, 436ORGANIC CHEMISTRY. 59are again considered, and, on the basis of physical measurments,preference is given to the older unsymmetrical constitut*ion. Bysimilar methods, the structure of ethyl succinylmalonate is like-wise claimed to be unsymmetarical, and as this view has to bereconciled with tihe current opinion that succinyl chloride is sym-metrical, an ingenious structural scheme, which overcomes thisrlifficulty, is submitted in the original paper.Much patient work has been devoted to studying the condeiisa-tion react'ions promolted between ethyl oxalate and substitutedethyl crotonates by potassium ethoxide, but the subject does not,lend itself readily to synopsis. I n the case of the reaction betweenthe oxalic ester and ethyl 8-aminocrotonate, the change is simple,and consists of the elimination of alcohol followed by enolisationof the product.36 When, however, the aminocrotonate is replacedby the corresponding ethoxy-ester, a complex reaction ensues andthree molecules of alcohol .are removed :The potassium derivative thus produced undergoes a furtherinteresting change when acidified, as the ethoxy-group is theneliminated, with the fotmat,ion of the triketone,A compound of this nature offers considerable scope for possibleenolisation, and a lengthy paper is devoted to a description of itssomewhatl complicated reactions.37Optical A ctivitfy.It is perhaps necessary to point out that, although the subjectof optical activity has recently been dealtl with a t some length inthis section of the Annual Reports, the treatment has not beencomprehensive in that the policy has been followed of restrictingdiscussion to new results furnished exclusively by aliphatic com-pounds.The writer is of the opiiiioii that this policy, which wasoriginally adopted t o avoid t'he possibility of optical activity beingrelegated to '' No Man's Land," should not in the future be rigidlyadhered to, and that the scope should be sufficiently elastic toinclude observations on all types of optically active substances.On the present occasion, some overlapping with other sections ofsu W.Wislicenus and K. Schallkopf, J . p. Chem., 1917, [ii], 96, 174; A.,i, 157. 57 Ibid., 95, 269; A., 1917, i, 700the Report is inevitable so as to include reference to a strikingresearch which adorns the opening pages of the latest additionto periodical chemical literature.The work of Werner and his school 011 the activity of cobalt-arninines has recently been expanded by t7he study of a series ofcompounds coiitainiiig bath cobalt and carbon asymmetricsystems.38 In directing attention to t.his development, it is feltthat any attempt to discuss the results in an abbreviated form isliable to do injustice to an important piece of work, and the readeris referred to the original paper or the published abstract.The essential principle iiivdved in the research is that the cis-typeof the general compound (XCoen,)X can exist in two structuralforms when one of the ethylenediamino-residues is replaced by anu n s y ~ e t r i c a l diamino-group.This idea has been verified by theisolation of two series of @avo-salts (termed a and /3) correspond-ing with the two structural varieties of the parent ammine, andalso by the number of isomerides obtainable when the unsyni-metrical diamino+componentl is likewise optically active. Takingthe general case, where the asymmetric carbon and cobalt sysfmsare represented, respectively, by A and B, the total number ofoptically active flnzwsalts theoretically possible should be eight,as shown below:I A .d B a and p‘4 A . d Bd ’ A . 1 Bl A . 1 B 1 These should exist in two groups of four, one series conformingto the a- and the other to the P-type. The experimental resultsobtained by Werner conform accurately to the prediction, and alsoinclude the isolation of the following partly racemic compounds :1. Racemic with respect to A:2. Raceinic with respect to B :The fact that, in addition, the two completely racemic compoundsto, which the abolve lead have likewise been obtained does notexhaust the results of a highly interesting research, the successfulprosecution of which must have made esceptionally heavy demandson the experimenters concerned.The painstaking and laborious work devoted during the past8 8 A.Werner, Helu. Chim. Actu, 1918, 1, 6 ; A., i, 375ORGANIC CHEMISTRY. 61twenty-five years to the quantitative study of optical activity iiicarbon compounds has revealed many and unexpected complica-tions, but, despite the fact that the ultimate goal is yet remote,investigators i n this field do not allow their enthusiasm to flag.New results and fresh difficulties follow one another in quizksuccession, and i t is highly desirable that, from time to time, thesit,uation should be broadly reviewed. Bold speculation is neededif our ideas are to be saved from becoming stereotyped, aiid inrecent years the pages of the Journal bear ample testimony to thefact that, in this respect, the subject' is well served.There canbe few more important issues in optical activity than the causesand mechanism of the Walden inversion, but work on this subjectis restricted by the absence of any rigid tests whereby a change inconfiguration, as distinguished from a change in sign, can bedetected with certainty. I n this connexion, considerable import-ance must be attached to a recent paper in which an earlier seriesof researches on optically active a-hydroxy-acids has been extendedto include a-amino-acids.39 An attempt is made t o lay down prin-ciples which would lead to the recognition of the configuration ofsimilarly constituted compounds, and the literature of the subjecthas been thoroughly explored, so that the discussion is based oncomprehensive evidence.It is with considerable reluctance thatthe writer of this section of the Report, refrains from any attemptto give a condensed accountl of the work, but it is felt that anyinterference with the consecubive and closely reasoned argumentwould only lead to confusion.Research on the effect. of solvents in influencing optical inversionshas now been applied to the important case in which bromine isdisplaced by the amino-group. It is found that in the particularcase of Z-phenylbromoacetic acid ,40 the amino-acid produced isopposite in sign when the displacement is carried out in aqueousor alcoholic solution. The results furnished by the lower alcoholsare, however, in some measure irregular, in that considerableracemisation takes place in these solvents, and, in additlon, it willbe remembered that they do not occasion a change of sign whenused as the media in which phenylchloroacetlic acid is convertedinto pheiiylaminoacetic acid.The results cont,ributed in this andthe succeeding paper,4l together with the discussion on the prob-able mechanism oE the decomposition of halogen compounds, are o€obvious importance in the synthesis of optically active amino-acids.39 G. W. Clough, T., 1918,113. 526.40 G. Senter and S . H. Tucker, ibid., 140.41 G. Senter, H. D. K. Drew, and G. H. Martin, &id., 161Turning to the related problems presented by racemisatioiiphenomena, interest will be taken in new results which have beenobtained in the phenylsuccinic acid series.I n the particular caseof compounds conforming to the tartaric acid type, change in con-figuration may give rise to either meso- or d-tl-forms, the resultin either case being regarded as racemisation. It" has now42 beenestablished that the methyl and ethyl esters of r-diphenylsuccinicacid can, like the parent acid, be converted into the correspondingmeso-varieties, and, further, that the act'ive esters behave in asimilar fashion. These changes are encountered during the processof partial hydrolysis, and the most striking feature of the resultsis the observation that the non-hydrolysed ester is largely racemiseclthrough conversion into the meseform.43 In fact', it appears thatthis is to be regarded as the principal source of 6he racemisationrather than the optical rearrangement of the liberated acids.Asthese results are not confined t o any one type of compound, it canno longer be assumed that change in configuration involves ofnecessity the permanent removal of a group from an asymmetricsystem. This is already recognised, as a number of weli-authenticated cases of auto-racemisation are now know I, and theexample presented by optically adive benzoin may be cited as acase in point, but it is somewhat disconcerting to find anotherspecies of auto-racemisation extending to the case of esters.It is a curious factl that some of the most striking results corre-lating the magnitude of specific or molecular rotation with con-stitution have been obtained with compounds of complex con-figuration. An additional example of this is furnished in areview of the optical activities displayed by polyhydroxy-acidamides, a number of new examples of this type of compoundhaving been rendered available as a result of Weerman's work 011the degradation of sugars.Comparison of their optical activitiesshows that the sign of the rotation of the amides is determinedchiefly by the position of the hydroxyl group attached to thea-carbon atom, and is largely independent of the optical effect ofthe remaining asymmetric systems. When the formulae arewritten as below, the product is dextrorotatory if the hydroxylgroup is situated below the chain of carbon atoms, and is laevo-rotatory with the reverse configuration.H OHOH-CH,*[ CE*OH],* &CO N H2 OH*CH,* [ CH*OH J n .6 COON H,i)H HDextro. Laevo.42 H. Wren and C, J. Still, T., 1917, 111, 1019.48 H. Wren, ibid., 1918, 113, 210ORGANIC CHEMISTRY. 63Accepting this view, which applies t,o cases other tphaii khosequoted by Hudson,44 it is possible to ascribe a definite configurw-tion to active hydroxy-acids where the a-carbon atom is asym-metric, and the evidence thus obtained supports Fischer’s formulafor d-tartaric acid, Z-malic acid, and d-glyceric acid. Incidentally.the conclusions arrived a t are in agreement with the configurationsassigned by Freudenberg to malic and glyceric aci-ls on the basisof the production of d-glyceric acid from Z-isoserine.This generalisation denialids that one.asynimeti<c system exertsa preponderating influence on the activity of a molecule which maycontain asymmetric atoms, and that this is frequently the case isnow recognised . Additional evidence pointing to the directinginfluence on rotation of one particular position in 8 molecule isalso furnished by a recent paper 45 which deals exclusively with thespecial case presented by substitution in the benzene nucleus.Here, again, the generalisation emerges that the greatest opticaleffect is exerted when substituting groups are introduced in spatialproximity to the asymmetric carbon atom.Carbohydrates.During the past year, as has recently been t-he case, a consider-able amount of work has been done on the preparation of variousacetylated sugars.46~ 47 The methods employed show little or nodeparture from standard processes, but the work has been directedmainly to the isolation of pure stereochemical forms and t o a studyof the conditions under which these may be int<erconverted.Inview of the discovery, to which reference was made in a previousReport,4* that a t least four definite galactose penta-acetates exist,research of this description acquires a new importance, and, inaddition, ths optical rotations of substituted sugars which are thusrendered available are of value in testing generalisations corre-lating optical rotatory power and constitution in the sugar group.As is well known, the late J. U. Nef devoted the closing yearsof his life to an elaborate study of the condition assumed by sugarsin alkaline solution, and it is gratifying to find that additionalresults are now forthcoming49 in which the work is extended to thecases of Z-arabinose and Z-xylose.As was to be expected, these44 C. S . Hudson, J . Amer. Chem. SOC., 1918, My 813 ; A., i, 292.45 J. B. Cohen and Miss H. 5. de Pennington, T., 1918,113, 67.46 C. S. Hudson and J. K. Dale, J . Amer. Chem. SOC., 1918, 40, 997; A.,47 Ibid., 992 ; A., i, 335.1917,39, 1638 ; A., i, 100.i, 335.48 Ann. Repwt, 1916, 84.J. U. Nef, 0. F. Hedenburg, and J. W. E. Glattfeld, J . Amer. Ohm. Soc.sugars, when oxidised in alkaline solution, give rise to a largevariety of oxidation products, and the result,s n o t oiily serve toemphasise the extremely coiiiplex nature of a reducing sugar inthe alkaline state, but are in agreeineiit with the structural viewsexpressed by Nef in his earlier papers.-* Nef’s ideas also serveto account for bhe effects which have been observed during theoxidation of maltose in alkaline solution,sl and, looking back 011the publications in which this particular type of sugar oxidationwas first discussed, the impression remains that inadequate recog-nitioa has been accorded t o an extremely fine piece of work.Xnoteworthy example illustrating the practical application of theseideas is furnished by the successful conversion of rhamnose intomethyltetronolactcsne by the simple process of dissolving the sugarin alkali and passing air through the solution.p2 From the bio-chemical point of view, the whole question of the oxidatlion ofsugars under niild conditions is impcrtaiit<, and signs are not want-ing that interest in the subject is being revived.53The interruption of research due to war conditions has delayedthe development of systematic work on the specially reactive formsof reducing monosaccharides which are included under the pro-visional name “y-sugars,” but reference can be made to a paperon the subject which has appeared during the past, year.54 It isnow established that in addition t.o the two crystalline methyl-galactosides, a third, noii-crystallisable form exists, and i t is shownthat this variety is analogous in structure to y -methylglucoside.When completely methylated and the product thereafter hydro-I ysed, tetramethyl -/-galactose is obtained, and this substance pre-serves the reactivity which is characteristic of the y-series.Thefact that the methylated sugar undergoes spontaneous auto-condensation on keeping, and is thereby converted into an octa-methyl y -digalactose, is a sufficiently st’rilring example of thisreactivit-y to deserve special mention. As a side issue of theresearch in question, another interesting result emerges. In hisoriginal preparation of methylgalactoside, Fischer isolated anamorphous product which he regarded a t the time as a thirdvariety of the simple galactoside. It now appears, however, thatthis substance is a methyldigalachside, and its formation furnishesanother example pointing to the idea t-hat the most ready route toAnn.Report, 1914, 84.51 J. W. E. Glattfeld and M. T. Ranke, J. Amer. Ghern. Soc., 1918, a,52 C. S. Hudson and L. H. Chernoff, ibid., 100.5 ; -4., i, 336.83 L. Bercaeller and E. Szeg6, Biochem. Zeitsch., 1917, 84, 1 : A . ,973 ; A., i, 336.i, 101Miss M. Cunningham, T., 1918, 113, 596ORGANIC CHEM TS‘T‘RY. 65tJie synthesis of di- and poly-saccharides is through the y-form ofreducing hexmes.Another important step has been gained iii the identification ofy-sugars in a structural study 55 of the crystalline variety of methyl-fructoside recently isolated by Hudson. This compound is t3heonly known homogeneous niethylfructoside, and can thus be con-verted by standard processes into a tetramethyl fructose which isa definite chemical individual. The compound actually obtainedis identical with one of the tetramethyl fructoses previously pre-pared by Purdie and Paul, and, as a result’, it is now possible toconstruct! a scheme illustrative of the complex changes which ensuewhen fructose is treated with acid methyl alcohoi.The ketose,like glucose, behaves both as a butylene oxide and as an ethyleneoxide, and thus gives rise to a t least four fructosidea, two of whichare derived from y-fructose. It is significant that fructose shoulddisplay this ready tendency to react in t’he y-form, particularly asit. is the same form which is present in sucrose.A t the same time, it inwt be recognised that although y-sugarsevidently play an important part in natural processes, other varia-tions of the sugar molecule are ofteii functional.Thus, the pre-diction made by Fischer some years ago that “glucal ” would befound to exist in natural conibinatioii is now realised, as the(‘ carbohydrate group ” in the nncleic acids has been identified asglucal, a i d not glucose. as has hitherto been supposed.56So far as synthetic work in the sugar group is concerned, themost outstanding piiblications of the year deal with the formationof glucose arid fructose derivatives in which .elected hydroxylgroups are substituted. Details need not be given of the methodsemployed t o limit the substitution to particular positions, as thesenow present no novel feature, having been standardised in thepreparation of partly methylated sugars.The first of the papers5’refers to the formation of definite mono-, di-, and tetra-benzoyl-glucoses, and of these, -the most striking is the mmobeiizoyl com-pound, which is apparently identical with the vacciniin ” isolatedby Griebel from the whortleberry. The constitution of the newsugar, considering its mode of formation, must be analogous tothat of mononiethyl glucose,58 and may thus be regarded asC €4 (OSz) *C I-1 (OH) CH [ C H*OH],* CH*OH v055 Miss E. S. Steele, Y’., 1918, 113, 857.56 R. Feulgen, Zeitsch. p&&ol. Chem., 1917, 100, 241 ; A., i, 85.5 7 E. Fischer and H. Noth, Ber., 1918, 51, 321 ; A., i, 225.58 J. C. Irvine and T. P. Hogg, T., 1914, 1386.REP.-“-VOI,. XV.166 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRYThe dibenzoylglucase prepared does not seem to have beeuexamined in detail, but in all probability it is likewise representedin nature, as a well-defined dibenzoylglucoxylose has been foundin the leaves and stems of Daviesia latifolia.Work on similar lines has been successfully extended to fructose,but it may perhaps be pointed out, that the question of structurein these partly substituted hexoses is beset with difficulties, as, inaddition to determining the position of the subst.ituting groups,experience has shown that it is necessary b discriminate bebweenthe ethylene oxide and butylene oxide types.The problem of synthesising sugar derivatives comparable withthe tannins has again been revived,5Q and here also advantage hasbeen taken of glucose mono- and di-acetones, which have been con-verted, respectively, into tri- and mono-gallolylglucoses.Thetrigallolylglucose, however, differs in properties from chebulic acid,and the monogallolyl derivative is not identical with Feist's gluco-gallic acid. It may be mentioned that, as a preliminary to thework just described, a renewed attempt has been madem to obtainpdigallio acid with the ultimate object of preparing from it thecorresponding chloride for use in the synthesis of tannins. Penta-acetyl-p-digallic acid was actually obtained, but, on removing theacetyl groups by carefully regulated hydrolysis, the product provedto be m-digallic acid. The transformation thus involved is ofgeneral interest, and attention should be directed to it.GZzccosides.-Under this heading, only one paper need be con-sidered.I n previous Reports, reference has been made to thethioglucosides prepared from glucope ethyl mercaptal by the actionof mercuric chloride, and it now appears that this particular reac-tion is generaI,61 giving rise uniformly to a-thioglucmides. Thecorresponding &compounds may, however, be obtained by actingon acetobromoglucose with the potassium salts of mercaptans, andt'he published description of these compounds leads to the opinionthat they are true glucosides containing a *five-membered ring inwhich oxygen is replaced by sulphur.Disaccha&fes and Polysaccharides.Although the publications dealing with di- and poly-saccharidesare not numerous, several strikingly important results have to berecorded.Authentic syntheses of disaccharides are few in number,and, excluding those based on the function of enzymes, are charac-5 9 E. Fiischer and M. Bergmaon, Ber., 1918, 51, 298 ; A., i, 224.E. Fiacher, M. Bergma,=, and W. Lipschitz, ibid,, 46 ; A., i, 172.W. Schneider, J. Sepp, and 0. Stiehler, dM., 220 ; A., i, 262ORGANIC CHEMISTRY. 67terised by the use of processes which are drastic and are in nusense parallel to natural synthesis. It is possible, however, tocouple reducing hexoees when they are in the form of y-sugars bycomparatively mild agencies to give products which are glucosidesof di- and poly-saccharides.62 To take an example, when galactoseor glucose is dissolved in methyl alcohol containing a trace' ofhydrogen chloride and the solution concentrated, glucoside form-ation takes place, and simultaneously hexose residues are coupled,so that the ultimata products are respectively methyltetra-galactoside and methyltetraglucoside.In tqhis simple way, it ispossible to form complexes of high molecular weight, and the readyconversion of maltose into a methyltrimaltoside containing thirty-seven carbon atoms furnishes a striking case in point.Interest in thio-derivatives of sugars is reviving, and a newdeparture is marked in a paper describing the synthesis of adefinite thioisotrehalose. By the action of potassium sulphide onacetobromoglucose, the octa-acetate of a thiodiglucose was obtained,and this was converted into the parent thiodisaccharide by theaction of alcoholic ammonia.03 The corresponding selenium com-pound has also been obtained, and as both sugars are crystalline,they have been carefully characterised.It is doubtful, however,if these disaccharides are normal in structure in view of theirbehaviour on hydrolysis and ready capacity to form monopotassiumsalts, but this does not detract. from the inherent interest of thecompounds.Turning t o problems of constitution, the important workdescribed last year on the structure of sucrose has been followedby a similar constitutional study of lactose.64 The method adoptedconsisted, as ustial, of complete methylation, followed by hydro-lysis, and the following scheme illustrabes the essential steps :Lactose + methyl-lactoside + heptamethyl methyl-lactosideTetramethyl hexose ( A )/ 7--3 Methyl alcohol\ Trimethyl hexose ( B )The work thus focussed on the identification of the two methylatedhexoses produced and in the allocafion of the methyl groups.Theproduct ( A ) proved to be the butylene oxide form of tetramethylgalactose, whilst the remaining product ( B ) was remgnised as tri-methyl glucose, identical with that isolated by Denham from82 Miss M. Cunningham, T., 1918,113, 804.6s F. Wrede, Bwchem. Eeitflch., 1917,83, 96; A., i, 6.W. N. Haworth and Miss G. C. Leitch, T., 1918,113, 188.u methylated cellulose. The provisional constitution assigned to thismethylated glucose is now confirmed, and i s consequence the com-plete structure of lactose may be represented by the followingformula : c: I3 2 0 1iI-CH--- O--cH~ H - O H6 H 013(Galactose residue.) (Glucose residue.)Incidentally, the results have also a direct.bearingstitation of melibiose, and work of this descriptionon the con-goes far toclear up many outstanding problems in the disaccharides. One ofthe most significant features of ths new observations is the experi-mental evidence pointing to the existence in the case of lactose ofwhat has long been expected, namely, the coupling of hexose resi-dues through secondary alcohol groups. I n view of these positiveresults, i t is perhaps superfluous to mention an argument,Gj basedon the negative evidence that. lactose fails to form an o-tolyl-hydrazone, that the disaccharide is best represented by the un-branched chain structure originally assigned to it by Fischer.Considering current views, it is possible that some workers willbe disposed to disagree with the inclusion of cellulose as a subjectof discussion under the heading polysaccharides.A few yearsago, the idea that cellulose must be regarded as a polyglucoseseemed definitely settled by the confident claims made by Will-statter that the coniples could be converted quaiititatively intoglucose. Repetition of this work, under conditions which werecertainly no less accurate, has materially weakened the force ofWillstatt'er's argmment.66 It is manifestly impossible to estimate,by means of polarimetric observations, the amount of glucose pro-duced in a system saturated with hydrogen chloride, as this acidproduces profound constitntional changes in the sugar.Estima-tions of reducing power are equally valueless. Some idea of thecomplexity of the changes involved in the hydrolysis of cellulose isshown by the observation that purified cotton or esparto celluloses,when degraded by mineral acids, are converted into a series ofpolysaccharide esters. These are capable of forming stable bariumsalts, and the presence of acidic hydroxyl groups is thus indicated.A. W. van der Haar, Rec. trav. chim., 1918, 37, 251 ; A,, i, 212.66 Miss M. Cunningham, T., 1918,113, 173ORGANIC CHEMISTRY. 69T h s feature is not characteristic of normal polyglucoses, and theresult is disconcerting.I n a further paper,G7 by authors whoseexperience in this subject commands respectful attention , a pleais made for discarding old views and for making a fresh start' inelucidating the structure of cellulose. Considering the complexi-ties of the problem, the experimental method based on a study ofthe products formed on dry distJllation under diminished pressuremust appear somewhat crude, but the results obtained are notuiiworthy of attention68 Apparently I-glucosan is produced innotable yield, and arising out of this observation, the claim hasbeen made that both starch and cellulose are tlo be regarded aspolymerides of Z-glucosan, to which the structureHO*HC----C H-OHI I H( '-f)----CMI IH,C-O---- CH-OHis assigned.69 The above formula is ingenious, but it does notaccount for the isolation of the particular form of trimethyl glucosewhich is obtained from methylated cellulose by hydrolysis.70I n a previous Report, reference has been made to investdgationson the degradation of starch by means of formaldehyde.Thiswork is being cont*inued, and although a good case may yet bemade for the claim that the reactions involved show a strikingsimilarity to those occasioned by diastase, the experimental methodsemployed seem elementary and do iiot carry conviction.71~ 72.Titroyerz Compoicuds.Less space than usual need be devoted t o the consideration ofaliphatic nitrogen compounds, as, judging from the publishedresults, recent, work has been conducted on orthodox lines. Someyears ago, Meisenheimer gave expression to his views regarding thedistribution of the nitrogen vaIencies i n ammonium compounds,and although his opinions were based on the results of speciallydesigned experiments, they were promptly challenged by Fromm.I n the interval, little has been heard of the discussion which ensuedhetween these workers, but an authoritative opinion 73 has now0 7 C.F. CIOSS and IC. J. Eevnn, T., 1018, 113, 182.6 8 A. Piutet mid J. Sitrnsin, Conhppc. v t ?id.. l!) L8, 166, 3 s ; A . , i, 5!).C 9 J. Sarasin, -4rch. S'ci. phys. nut., 1918, [iv], 46, 5 ; -4., i, 375.7" W. S. Denham and Miss H. Woodhouse, Y'., 1917, 111, 94.4.7 1 H. Maggi and G. Woker, Be/*., 1918, 51, 790 ; A., 1, 37.5.7 2 Ibid., 1917, 50, 1188; A., 1917, i, 686.S .Komatsu, Mew. Coll. Sci. Kyi;to, 1918, 3, 151 ; L4., i, 466been expressed independently. A review of the properties ofknown quaternary compounds leads t.0 the conclusion that four ofthe nitrogen valencies are inter-equivalent, and may be regardedas occupying the apices of a tetrahedron, whilst the fifth principalvalency is external, but nevertheless has a fixed position for anyindividual compound. In one respect, we are thus invited tochange our views, but a compromise is possible, as this definiteposition may vary according to the method whereby the ammoniumcompound is prepared. This is not imfirobable, and the adoptionof the proposal, which is certainly free from an element of vague-ness which characbrised Meisenheimer’s ideas, accounts satisf ac-t’orily for the existence of two distinct forms of d-phenylbenzyl-methylallylammonium iodide, and also for the isomerism displayedby the semi-ethers derived from trimethylamine oxide.Amongst numerous new experimental results, mention shouldbe made of a substantial simplification which has been introducedinto the preparation of etbylamine and diethylamine through theaction of ethyl bromide on alcoholic ammonia.74 When conductedin the cold, and when the addition of the alkyl bromide is regu-lated so that the excess of ammonia is maintained a t a fixed ratio,practically no tertiary amine is formed.Further the separationof the primary and secondary amines can be readily effected bytaking advantage of the widely different solubilities of ths corre-sponding hydrobromides in chloroform.Another useful paper75 devoted to a detailed account of thepreparation of dirnethylglyoxime is specially noteworthy in viewof the public-spirited policy which it reflects.Itl is the first of aseries of publications dealing with the preparation of the lessaccessible organic compounds, and describing the working methodswhich have been found most, efficient. The scheme will un-doubtedly attract much attention, and will be followed by chemistswith interest and appreciation.Catalytic methods for preparing nitriles are now almost bewilder-ing in number. Not only may the dehydration of aldoximes76 beeffected by the use of thorium oxide at 34OoY but- the same reagenta t a higher temperature can bring about t-he catalytic condensationof aldehydes and ammonia, the change being followed by loss ofwater, and presumably of hydrogen als0.7~ It- is doubt-ful if thesemethods will prove as generally useful as the corresponding process74 E.A. Werner, T., 1918,113, 899.?aR. Adams and 0. Kamm, J . Amer. Chew. Soc., 1918, 40, 1281; A . ,76 A. Mdlhe and 33’. de Godon, Bull. SOC. c?bh., 1918, [iv], 23, 18; A.,7 7 Idem, Compt. r e d . , 1918,166, 215 ; A., i, 106.i , 482.i, 105ORCfANlC CHEM1STRY. 71depending on the interaction of an eater and ammonia in presenceof aluminium or thorium oxide?I n recent Reports, considerable space has been devoted to thechemistry of carbamides, and although a number of papers on thissubject have appeared during the past year, they are concernedchiefly with the continuation of earlier work which has alreadybeen fully discussed.More than a passing reference should, how-ever, be made to work which entirely alters our views regardingthe constitution of the substances known as isoamides or h i n o -hydrins. These compounds, which are prepared by the decomposi-tion of imino-ether hydrochlorides by means of moist) silver oxide,were originally regarded as conforming to the type OH*CX:NH,but this structure was afterwards modified by Hantzsch so as toaccommodate the fact that the molecular weights are twice themagnitude demanded by the simple formula. The structure thensuggested (NH:CR*O*NH,:CR*OH) is also. open t o criticism, andbreaks down when tihe conductivities of iminohydrins are takeninto consideration.As amphoteric electrolytes, these compoundsshould display low conductivity, whereas the reverse is the case,the results actually obtained being comparable with the valuesgiven by a true salt. Then, again, although Hantzsch’s formuladoes not demand that iminohydrins are derivable only from a-hydr-oxy-acids, this restriction seemed at one time necessary, as alliminohydrins previously known were obtained from this type ofacid. Such a view can no longer be held, and all the evidencenow available points to the idea that the iminohydrins are inreality amidine salts.79 The nature of these salts is perhaps notvery clear from the general formula NH,*CR:NH,R*CO,H, andwill be best understood by the verbal description that “glycoll-iminohydrin ” is to be regarded as glycollamidine glycollate. Theresearch now under review was initiated by conductivity measurements on the amidine salt8, and ended with their synthetical form-ation on lines conforming to the above structure, and thus furnishesa good example of the searching test which physical methods canbring to bear 011 problems of structure. From this point of view,i t is regrettable that the conductivity of boric acid is but littleaffected by the addition of compounds containing the group*NH*CO*, and thus the application of Boeseken’s method of testingconstitution is meanwhile excluded from a number of importantcompounds.80A.Mailhe, Cwnbpt.rend., 1918, 168, 121 ; A., i, 106.7 9 H. G. Rule, T., 1918, 113, 3.**&J. Bbeseken [with W. Sturm and G. Goettech], Rec. trav. c h k . , 1918,37, 144 ; A., ii, 146Little progress has been made with research on amino-acids, .andno novelt4ies have been not'ed, but a welcome will be accorded to auseful paper 81 describing the most f avourable experimental con-ditions for preparing typical phosphotungstates. Although thesecompounds may not be specially suitable for the purpose ofidentifying amino-acids, they retain a certain value in processesof isolating and purifying individual constituents of mixtures.Fresh information on the chemistry of proteins is distinctllyscanty and unconvincing, the results obtained in the oxidation ofthe complexes by nitaic acid or in the methylation by means ofdiazomethane being too indefinite ta lead to any enlightenment.The extensive scheme of research on the azides derived fromcarboxylic acids, to which reference was made last year, has nowbeen brought to a conclusion by the extension of the work t o alarge number of amino- and substituted amino-acids.82 As in theearlier papers of the series, the desired compounds have beenobtained by well-known processes, and their reactions display noessential novelty, although, concealed within a mass of experi-mental results, a number of improved working methods may befound.Very much the same remarks can be applied to the latest paperon the hydrazides and azides of organic acids,8S and to what' isevidently the first of a series of publications on the formation andproperties of hydrazino-acids.84 On the whole, it is evident? that,although research on aliphatic nitrogen compounds has beenenergetically pursued during the past year, a stage has beenreached which is characterised by t.he absence of any noteworthydiscoveries.J.\ams COLQUHOUN IRVINE.d l J.C. Drwnmond, Biochem. J., 1918, 12, 5 ; A . , i, 336.s2 T. Curtius, J. PI-. Chent., 1917, [ii], 95, 327 ; R., i, 44.fi3 T. Curtius a.nd 0. Hofmann, ibid., 96, 202 ; A . , i, 293.S4'A. Dsrwpsky, ibid., 251 ; A . , i, 506ORGANIC CHEMISTRY. 73PART 11. --HOMOCY CLI c DIVISION.Reactions.Catalytic Reduction .-The period under review has broughtforth a number of papers on reduction with hydrogen gas in thepresence of various catalysts.The most important of thesedescribes a general method for the preparation of aldehydes bythe reduction of acid chlorides.’ At the outset, it appmred to bedesirable to work a t a law temperature with the calculated quantityof hydrogen in order t o avoid further reduction t o the alcohol, toemploy as a solvent ether, which would neither react with the acidchloride nor ‘poison’ the catalyst, and t o iieutralise the hydro-chloric acid produced in the reaction, by the addition, for instance,of calcium carbonate. Numerous modificat.ions of these conditionsonly permitted the formation of a trace of benzaldehyde from1)enzoyl chloride, but eventually a met.hod was discovered by whichthe reaction could be carried out with nearly the theoretical yield.The conditions were the reverse of those anticipated, hydrogenbeing passed t,hrougli a boiling 20 per cent.solution of benzoylchloride in xylene until the escaping gas 110 longer containedhydrogen chloride, indicaied by the formation of a cloud withammonia. Palladinised barium sulphate or Kelber’s nickel wasemployed as catalysts. Benzoyl, butyryl, and stearyl chlorideswere thus converted into the corresponding aldehydes, and tri-carbomethosygalloyl chloride into t~icarbomatho;uye;nllaldehyde.which gave gallaldehyde on gentle hydrolysiv.2There is evidence to show that in reductions hy hydrogen gas inthe presence of platinum, tLhe presence or absence of oxygen in thecatalyst may make a considerable difference to the result.111 thereduction of the anhydrides of o-dicarboxylic acids, it is found ,tobe necessary to ‘prime” the catalyst occasionally by shaking itwith air, otherwise the absorption of hydrogen ceases. Employ-ing this method, phthalic anhydride yields as primary productsphthalide and oitoluic acid, indicating t’hat the five-membered ringis reduced first. Subsequently, hexahydrophthalide, hexahydro-o-toluic acid, and hexahydrophthalic acid are produced. In thereduction of phthalimide, however, it is the benzene ring oiily thatsuffers reduction, the sole product of the reaction being hexahydro-1jhthalimide.3K. W. Rosenmund, Ber., 1918,51, 586 ; A., i, 300.K. W. Rosenmund and F. Zetzsche, ibid., 594; A., i, 300.R.Willstlitter ~ n c l l3. Jaquet, ibid., 767 ; A . , i, 391.D74 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRYAn attempt 4 to reduce o-nitrostyrene to P-nitroethylbenzene inalcoholic or acetic acid solution by hydrogen in the presence ofplatinum-black was unsuccessful, the productl being as-dinitro-Py-diphenylbu tam, N02*CH,*CHP he CHP h* @H,-NO2. The reductionof o-nitro-3 : 4-methylenedioxystyrene gave a similar result.Furthermore, catalytic reduction has been employed in the pre-paration of 2 : 3-dimethoxybenzyl alcohol from o-veratraldehyde,6and i n the conversion of alcohols, aldehydes: and acids of theterpene group into the corresponding saturated alcohols, aldehydes,and acids.6The removal of halogen from aromatic and other organic com-pounds by hydrogen in the presence of a catalyst has been thesubject of further work7 designed t o render the process morereadily applicable to tthe estimation of halogen in such compounds.Other papers record the superiority of colloidal palladium overcolloidal platinum as a hydrogen carrier: and the anticatalyticinfluence of mercury and other heavy metals.9The Sulphunution of P-Naphthylamiae.~Q-The action ofordinary concentrated sulphuric acid on 8-naphthylamine attemperatures below 80° leads to the formation of the 2:8- and2 : 5-naphthylaminesulphonic acids in yields of nearly 40 and 60per cent.of the theoretical respectively, whilst very small pro-portions of the 2:6- and 2:7-acids are formed as by-products. Onprolonged heating a t 80° to 120°, however, the 2 : 8-acid is gradu-ally converted, probably by way of repeated hydrolysis andsulphonation, mainly into the 2 : 5-acid, and to a small extent into2:6- and 2:7-acids.A t 150-160°, the last t'wo constitute themain product of sulphonation, being probably derived from the2 : 6 : 8- and 2 : 5 : 7-disulphonic acids by hydrolysis. The entiremechanism of the sulphonation of B-naphthylamine may probablybe represented as follows :'4 A. Sonn and A. Schellenberg, Ber., 1917, 50, 1513 ; A., i, 9.A. Kaufmann and H. Muller, ibid., 1918,51, 123 ; A., i, 178.C. Paal, B.R.-P., 298193 ; A., i, 181.C. Kelber, Ber., 1917, 50, 305 ; A., 1917, ii, 215 ; K. W. RosenmundC. Paal and A. Schwarz, ibid., 640 ; A,, i, 343. .* C. Paal and W.Hartmann, ibid., 711, 894 ; A., ii, 303, 357.lo A. G. Green and K. H. Vakil, T., 1918, 113, 35.and F. Zetzsche, ibid., 1918, 51, 578; A., i, 339ORGANIC CHEMISTRY. 7 5IJ.J.Orientation.K. J. P. Orhn and his co-workers11 have compared the directinginfluences of various groups in the chlorination of aromatic com-pounds by measuring the velocities of reaction, and have estab-lished for simple compounds bhe order NH2>0H)OAlk>NHAc.W. Fuchs12 has now arrived a t a similar result by examining theproducts of the bromination of paminophenol and its N-acetylderivative. The former gave 3 : 5-dibromo-4-aminophenol (I), theolrt’ho-directing influence of the amino-group being greater thanthat of the hydroxyl group, whilst pacetylaminophenol gave 2 : 6-dibromo-4-acetylaminophenol (11), the influence of the hydroxylgrmp predominating over that! of the acetylamino-group.OH OHFurther communications have appeared on the orientatinginfluence of the alkyloxy-groups in catch01 ethers, a subject whichwas reviewed last year.13 As the experimental material increases,it becomes more difficult to include all the results in generalisations.J.L. Simonsen and M. G . Raul* describe the nitration of 5- and6-acetylamino-3 : 4-dimethoxybenzoic acids and 4-acetylamino-verakrde.11 Ann. Report, 1916, 92.1% W. Fucha, Monatsh., 1917,38, 331 ; A,, i, 64.13 Ann. Report, 1917, 96. l4 T., 1918, 113, 22.1,” 76 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY-5 -Acetylamino-3 : 4-dimethoxybenzoic acid (I) yields the 6-nitro-acid (11) in accordance with their views,16 that the negativeOMe OMe NHA~()OM~ --.+ NHA&,OM~\/ NO)C02H\/CO,H(1.1 (11.1carboxyl group exercises no direct orientating effect except in sofar as it neutralises the methoxy-group in the para-position withrespect t o it, the nitro-group entering the orthwposition withrespect to the acetylamino-group and the para-position with respectto the second methoxy-group.The nitration of 6-acetylamino-3 : 4-dimethoxybenzoic acid (111) ,however, gave a result that they did not anticipate, the sole pro-duct of the reaction being 5-nitao-4-acet~ylaminoveratrole (IV),which was also obtained from 4-acetylaminoveratz-ole, whereas theyhad expected t o obhain the 2-nitro-acid (V).OMe OMe OMe/)oAfe -+ /\OMe /)oHe NHAJ I NHA~!,,NO,CO,H\/NO,NHAJ \/CO,H(nI4 W.) (V.)A second paper16 records that the nitration of 2-methoxy-m-tolualdehyde (I) gives a nearly quantitative yield of the 5-nitro-compound (11), whereas the 4-nitro-compound (111) had been/\ON0 ('OMe /\OMe I \ )CHO NO,,)GHO I '\/ ICHO(1.1 (11).(111).expectled i n view of the fact that o-veratraldehyde (IV)17 and5 : 6-methylenedioxy-o-tolualdehyde (V) 18 on nitration yield nitro-derivatives containing the nitro-group in the ort*ho-position withrespect t o the aldehyde group.Me Me MeNO2OMe MeW.) (V.1Is T., 1917, Ill, 224.17 W. H. Perkin, jun., and R. Robinson, ihid., 1914, 105, 2389.18 W. a. Perkin, jun., ibid., 1916, 109, 910.18 J. L.Sirnoneen, i f i d . , 1918, 113, 77577 ORGANIC CHEMISTRY.Miss F. Pollecoff and R. Robinson10 find that the nitration of5 -nitroguaiacol (I) yields mainly 5 : 6-dinitroguaiacol (11) in accord-ance with the view20 that negative groups in the meta-positionwith respect to a positive group exert an influence which is in thedirection 0f favouring ortho-substitution with respect to the positiveorientator, but a considerable proportion of the 4 : 6-isomeride (TIT)is formed at" the same time.(1-1 (11.1 (In.)Nitration of 3 : 5-dinitroguaiacol (IV), however, gave a singleproduct, the expected 3 : 5 : 6-trinit,roguaiacol (V).x 0,MeO?, HO/)N02R02(IV.1 (V.1The bromiiiation 21 of the two isomeric acetylaminoveratrolesand the three acetylainiiioveratric acids gave compounds in whichthe bromine atom entered the para-position with respect to theacetylamino-group in all cases where this position was free. Inthe case of 6-acetylaminoverati*ic acid (I), where this position wasalready occupied, the carboxyl group was eliminated with theformation of 5-bromo-4-acetylaminoveratrole (11).OMe OM e'\OMC? -+ BJ,)/)OMeC4H(,NHAc NHAc(1.) (11.)1Wigmtio92 of A cyl Group.s.-The crystallme digallic acid obtainedby the action of trimethylcarbonatogalloyl chloride on 3 : 5-di-methylcarbonatogallic acid and removal of the methylcarbonato-groups proved unexpectedly to be the meta- and not the para-compound.22 In an attempt to prepare t$he missing para-acid,triacetylgalloyl chloride was condensed with 3 : 5-diacetylgallicacid, when pentla-acetyl-p-digallic acid (I) resulted.On partiall'., 1918, 113, 645.20 T. G. €I. Jones and R. Robinson, ibid., 1917, 111, 903.21 J. L. Simonsen and M. G. Rau, ibid., 1918, 113, 782.22 E. Fischer and K. Freudenberg, Ber., 1913, My 1116 ; A., 1913, i, 47978 BNNUAI, 1LE;PORTS ON THE PROGRESS OF CHEMISTRY.hydrolysis of this compound, however, the known nz-digallic acid(11) was again obtained, which on reacetylation gave penta-acetyl-ni-digallic acid.23AGO AcO HOAcO- ACOAc O<->co 0 /-\CO,H: Ho(->co*oHO" Ha/-\ CO,H ,\-/\ /330-(7.1 (11.)It thus appeared that migration of the galloyl group hadoccurred in the parkial hydrolysis of penta-acetyl-pdigallic acid, asin that of pentamethylcarbonato-p-digallic acid.The investiga-tion was then extended to the examination of t.he beliaviour of thebenzoylacetyl derivatives of gallic and protocatechuic acids withsimilar result P . Thus, methyl 4 -benzoyloxy-3-acetoxyb enzoate(111) on partial hydrolysis yields methyl 4-hydroxy-3-beiizoyloxy-benzoate (V), which gives the isomeric methyl 4-acetoxy-3-benzoyl-o'xybenzoate on reacetylation. It is suggested that the methyl3 - hydroxy-4-benzoyloxybenzoat e, which is presumably the firstproduct, of the hydrolysis, may poesibly pass into the isomeric formthrough ail intermediate compound, such as that formulatedbelow (IV).OBZ OHThe study of steric hindrance in tertiary aromatic amines hasgiven interesting results.Dimethyl-o-toluidine (I) is much less reactive than dimethyl-aniline towards methyl iodide and in reactions involving substitu-tion in the para-pmition with respect to the nitrogen atom, forexample, introduction of the nitlroso-group or condensation withbenzaldehyde or formaldehyde.The extension of one of theN-methyl groups to form a ring, as in 1 : 8-dimethyl-l : 2 : 3 : 4-tetra-hydroqxinoline (11), was found previously t o be associated withdiminislie,l steric hindrance, and it has now been ascertained 2423 E. Fischer, M. Bergmann, and W. Lipschitz, Rer., 1918, 51, 46 ; A., i, 172.2* J. von Brawn, Z. Arkuszowski, and Z. Kohlcr, ibid., 282 ; A., i, 257ORGANIC CHEMISTRY. 79that the extension of the C-methyl group t o form a ring indimethyltetrahydro-a-naphthylamine (111) gives a similar result.cIEf2 C*,I I/\Me Me NMe CH, NMe,(1.1 (11.1 (111.)Ring formation is not, however, the principal factor in diminish-ing the steric hindrance, for dimethyl-p-xylidine (rV) is morereactive than dimethyl-o-toluidine, and dimethyl-o-3-xylidine (V)still more so; dimethyl-m-2-xylidine (VI), however, is even lessreactive.M e M e(IV.1 W e ) w.1It appears, therefore, that the introduction of a second sub-stituting methyl group neutralises the effect of the first to a largeextent when in the ortho-position with respect to it', and tQ asmaller extent when in the para-position. This behaviour finds anexplanation most readily if it is assumed that all the reactionsunder discussion depend on the preliminary anchoring of the react-ing molecule on the nitrogen, and that in dimethyl-o-toluidine theresidual affinity of the methyl group partly neutralises that of thedimethylamino-group, whereas in the compound (V) above, thesecond inethyl group largely saturates the residual affinity of theSrst methyl group and allows the residual affiity of the dimethyl-amino-group to come into play more readily.A similar attitude towards this problem is adopted by others,25who point out the non-reactivity of dimethylaniline oxide in sup-port of their view.The behaviour of nmthyl p-dimethylamino-beiizoate and pdimethylaminobenzaldehyde towards nitrous acidis ascribed Do the addition of nitrous acid a t the nitrogen atom,H<->NMe2(OH)*N0, whilst subsequent rearrangement gives inthe case of the ester the substances (I) and (11), and in the caseof the aldehyde the compounds (111), (IV), and (V).2A F.Klaus and 0. Baudisch, Rer., 1918, 51, 1036 ; A . , i, 43080 ANNUAL REPORTS ON THE PROGRESS OF CHEMlSTRY.(111.) (IV. 1 (V. )It was found some years ago26 that whereas the nitrogen atomsin the compound (I) reacted sluggishly owing to the sterichindrance of the methyl groups in the ortho-position, yet both thenitrogen atoms in the compound (TI) were reactive.(1- ) (11.1The lower hoinologues of these compounds, derived f r a nbenzidiiie instead of diphenylmethane, have now been examined,and it is found 27 that whilst N-tetramethyl-o-tolidine (111) fails toreact with cyanogen bromide and only combines sluggishly withiodoacetonitriIe, yet N-tetramethyl-o-methylbenzidine (IV) readilyyields the dicyanamide (V) with the first reagent and gives withiodoacetonit.rile a 30 per cent.yield of the dicyanodimethyl deriv-ative (VI).CN*N Me/-\--/-\NMe*CN '\-/ \-/Me(V.)C N C €I,* NMe/-\--/-\N Xe* CH,* CN \-/ \-/(VI.)MeTo steric influence is attributed the abnormal behaviour ofisovaleric acid in the Perkin synthesis.28 Benzaldehyde, isovalericanhydride, and sodium isovalerate yield ten times as much of thehydrocarbon (I) as of the unsaturated acid (11) a t looo.CHPh:CH*CHMe, CH PKC( CO,H)* C 11 Me,(1. ) (11.1CH Ph (OH) C H ( C02H) * CHMe,z.6 J. von Brmn m d 0. Ember, Ber., 1913,48, 3470 ; A., 1913, i, 1333.a5 J. von Braun and M.Mintz, ibid., 1917, 50, 1651 ; A., i, 127.a* A. Schamschmidf, E. Georgeacopol and J. Herzenberg, ibid., 1918, 51,(111.)1059 : A., i, 43181 ORGANIC CHEMISTRY.The hydrocarbon does not' appear to be formed directly from theacid, for this is stable a t looo, and it is suggested that the hypo-thetical primary product of the reaction, the hydroxy-acid, (111),first suffers the loss of carbon dioxide owing to the proximity ofthe isopropyl group, and then yields the hydrocarbon by dehydra-tion.CoZou,r and' Coitstit ution .C'ht-omoisomes.ism .--P. Pfeiffer has continued his . investigationof the occurrence of certain nitromethoxystilbenes in two forms ofdifferent colour, termed cryptoisomerides.29 His lahest paper dealswith t'he conditions which inust be fulfilled in order that nitro-stilbenes may be capable of exhibiting cryptoisomerism .4-Nitro-4/-methoxystilbeiie (I) exists in two varieties of different colour,and so also does 4-nitror2-cyano-4/-methoxystilbene. Introductionof the cyaiio-group into the $position, however, gives rise to acompound which occurs in one foim only. 2-Nitro-4-cyano-4'-iiiethoxystilbene (11) and the corresponding carboxylic acid, itssalts and esters, each occurs in two forms, but 2-nitro-4-cyano-2/(and 3')-methoxystilbenes only exist in one form. 2-Nitro-4-acetylaniino(and 4-benzoylamino)4~-methoxystilbenes also exist intwo forms, so that the phenomenon is characteristic of 2- and4 -ni tro-4 '-methoxystil benes .CN/-\C H :CR/-\OMe\-/ \-/(11.)/-~cH:cH/-\o&Ie \-/NO2(1.1After this examination of the influence of the positions of theabove groups, Pfeiffer deals with the effect of substituting ot-hergroups for the methoxyl group of 4-nitrc~-2-cyano-4'-methoxystilbene,and finds that its replacement by hydrogen or by alkyl groupsgives substances occurring only in one form.Its substitutionby hydroxyl, however, gives a substance occurring in twovarieties, but the acyl derivatives of this cornpound occur in oneform only. These results lead hiin to the view that nitrostilbenesonly occur in chromoisomeric forms when, besides the chrmo-phoric groups (the nitro-group and ethylene linking), an auxo-chromic group is also present. AttentioE is also directed to thefact that, of the two varieties, the paler coloured is similar incolour to the corresponding compound lacking the auxochromicgroup, whilst in the deeper colonred variety the typical auxo-chromic action comes into play.Zo Ann.Report, 1916, 108 ; 1917, 102 ; Ber., 1918, 51, 554 ; A., i, 34482 ANNUAL REPORTS ON THE PROGR,ESS OF CHEMISTRY.FZuorescence.-The fluorescence of platinocyanides indicates thatthe cyano-group has a favourable influence on this phenomenon,and it is kaown that even such a simple compound as benzonitrileis fluorescent in the ultra-violet. Like the platinocyanides, manyorganic cyanogen cmpounds are only fluorescent in #the solid state,for example, the compound CPh(CN) :CH*C,H,-NMe,. SinceN-methyl groups of ten inhibit fluorescence, the correspondingprimary amine, CPh(CN):CH*C,H,*NH2, was also examined, butproved to be less fluorescent in the solid state and devoid of thisproperty in solution.The isomeride of t'hhis compound, CHPh:C(CN)*C6H,*NH,, how-ever, showed a strong fluorescence both in the solid state and insolution, the contrast indicafing the effect of constitutional changeson fluorescence.A further number of somewhat disconnectedinstances of the relation bettween chemical constitution and fluores-cence are given in the same paper.30Synthe.sis of tz(ittirdly O C C U I ritzy C'omyoutids.The earlier syntheses of tropic acid, a hydrolytic product ofboth atropine and hyoscine, are too cumbrous to serve as methodsfor its preparation, but a simple and effective synthesis has nowbeen discovered. It is well known that ethyl phenylacetate canbe condensed with ethyl formate in the presence of sodium, yield-ing a mixture of desmotropic ethyl fomylphenylacetates.Onreducing this product with aluminium amalgam in ethereal solu-tion, ethyl tropate results.31 The reaction has been carried outindependently with the methyl esters.32CH,Ph*C02Et + CPh(:CH*OH)*CO,Et -+Elemicin, 3 : 4 : 5-trimethoxyallylbenzene, a constituent of thevolatile oil of elemi, has been synthesised by the following method.33The condensation of allyl bromide and pyrogallol 2 : 6-dimethylether yields 2 : 6-diniethoxyphenyl allyl et.her (I). This is con-CHPh( CH,* OH)*CO,Et.0- CB,*CH: CH, OH OMoMeO/\,Ol\lc ~ McO'\OMe ~ llcOf',OMe\/I t\/CH,-CK:CH, CH,* CH:C H,\/(1.) (11.) (111.)H.Kauffmann, Ber., 1917,50, 1614; A., i, 113.D.R.-P., 302737 ; A., i, 300.F. Mauthner, Annaten, 1917,414, 250 : A,. i. 428a1 E. Miiller, ibid., 1918,51, 262 ; A., i, 223 ; Chemische Werke Grenzach,"z. W. Wislicenus and E. A. Bilhuber, ibid., 1237 ; A., 3919, i, 19ORGANIC CHEMISTRY. a3verted by heating for a few minutes at 220° into 2 : 6-dimethoxy-4-al€ylphenol (11) , which yields elemicin (111) on methylation.The position of the ally1 group in the synthetic compound hasbeen determined by oxidation, when gallic add trimethyl ether isobtained.Curcumin, the colouring matter of tarmeric, is a substitutedderivative of dicinnamoylmethane,' and has the f omula givenbelow :OMe OMeIt has been synthesised recently by an application of the methodemployed previously for the synthesis of dicinnamoylmethane.34In this, cinnamoyl chloride was condensed with ethyl acetoacetateand the product hydrolysed, when cinnamoylacetone resulted.Con-densation of this product. with a second molecule of cinnamoylchloride and hydrolysis of the product gave dicinnamoylmethane.CHPh : CH C OCI + CHP h:C H CO @H Ac* CO,Et +CHPh:CH*CO*CH&c + (C€€Ph:CH*CO),CIHAc +(CHPh:CH*CO),CH,.By employiiig carboniethoxyferuloyl chloride (I) in the place ofcinnamoyl chloride, the dicarbomethoxy-derivative of curcumin wasobtained. It gave curcumin on hydrolysis.35OMeMeO,C*O/\ 1 ICH:CH-COCI \/(1.)By analogous methods, y-hydroxy- and pp'-dihydroxy-cinnameyl-methanes have been prepared.%A new synt.hesis of adrenaline has been described.37 Diacetyl-protocatechualdehyde (I), on condensation with nitromethane infeebly alkaline aqueous solution, yields B-hydroxy-8-3 : 4-diacetoxy-OAc OAc( y a c -+ (*C -?- fyAC \/' \CH(OH)*CH,*NO, CH(OH)*CH,*NHMe\/CKO(1.) (11.1 (TIT.)54 V.Lampe and T. Milobepdzki, Ber., 1913,443, 2236 ; A., 1913, i, 876.3s V. Lampe, ibid., 1918,51, 1347 ; A., 1919, i, 30.as V. Lampe and M. GodIewska, ibid., 1366 ; A., 1919, i, 31.s7 N. Nagai, Jap. Pats., 32440, 32441, 191884 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.phenylnitroethane (11). When this is mixed with the calculatedquantity of formaldehyde and reduced by means of zinc and aceticacid, 13-hydroxy-P-3 : 4-diacetoxyphenylethylmethylamine (111) isformed, from which adrenaline is obtained on removal of the acetylgroups.Ethylene Oaides.The preparation of many more complex ethylene oxides38 by theaction of sodium ethoxide on o-halogenoacetophenones in thepresence of aromatic aldehydes has been effected .Benzaldehyde has been successfully condensed with severalo-halogenoacetophenones containing positive substituents(CH,, OMe, NHAc),but no crystalline compounds were obtained when w-bromo-m-nitro-acetophenone or w-chloro-5-niti*o-4-acetylaminoacetophenone wereemployed.SBOn the other hand, w-bromoacetophenone has been subjected t othe action of sodium ethoxide in the presence of a large number ofaldehydes, and found to yield ethylene oxidss readily with thosecontaining negative substituents (NO,, C1, etc.), whereas no suchcondensation took pIace with aliphatic aldehydes or with certainaromatic aldehydes containing only positive substitiients, such asanisaldehyde and p-tolualdehyde.40It is suggested that the formation of ethylene oxides in thisreaction takes place according to the scheme:PhC?O*CH,Br + PhCHO + PhCO*CHBr*CH(OH)Ph -+HPhand is thus analogous to the condensation of acetophenone withaldehydes, where in certain cases ketonic alcohols have been isolatedas intermediate products.PhCOeCH, + RCHO --t PhCO*CH2*CH(OH)R +PhCODCHXHR.The tendency of simple ethylene oxides to yield the correspondingketones on heating alone or with catalysts,-CH*CH- --+ -CH,*CO-\/0is not.shared by the complex ethylene oxides under discussion, but38 Compare Ann.Report, 1917, 105.39 H. Jtlrlander, Bw., 1917, 50, 1457 ; A., i, 20.*O S. Bodforss, ibid., 1918, 51, 192 ; A., i, 229ORGANIC CHEMISTRY. 85change of this type can be brought about, by exposure of the sub-stance in methyl-alcoholic solution, to ultra-violet light, benzoyl-phenylethylene oxide, for instance, yielding phenyl a-hydroxystyrylketone.41PhUO*CH<8 HPh --f PhCO*C(OH):CHPh.Poly cyclic A To mat ic Hydro car b ons .Zndews.-Some years ago, C. Courtot 42 showed that Thiele’stheory of the oscillation of the double linking in the indene nucleuswas incorrect by isolating both 1- and 3-substituted indenes, forexample, 1- and 3-benzylindene. Thiele and his pupils43 havearrived at the same result by a slightly different method. Indene(I) is condensed with an aldehyde, R-CHO, and the product (11)is reduced, the resulting compound (111) being condensed with asecond aldehyde, R’oCHO, when the compound (IV) is obtained.-+C:CH R(1.1 (IT.)I \A/ CCHR/\(AI CH I OH,/1:CHR’(111.)I IBy conducting the same operations, but changing the order oftjhe addition of the aldehydes, the isomeric compound (V) isformed.Several pairs of isomerides have been prepared frmiaromatic aldehydes by this method.The stability of the two forms depends on the balance of theresidual affinities of the groups R and R’. To take an extremecase, where R is aromatic and R’ is hydrogen, compounds of them S. Bodforss, Ber, 1918, 51, 814; A ., i, 232.*? Ann. Repoyt, 1916, 117.49 J. Thiele and K. Merck, ArmaEen, 1918, 415, 267 ; W. Bernbhsen, ;bill.,274 ; H. M. Wiiest, ibid., 291 ; A . , i, 484, 488, 488$6 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.type (VI) cannot be isolated owing to the readiness with whichthey pass to the isomeric form (VII).C*CH,R/\/\ O\/CH C:CH,CXHR(VII.)Where both the groups R and R/ are aromatic, the two varietiescan usually be isolated, but may differ in stability. Thus, l-benzyl-idene-3-p-methoxybenzylindene (VIII) is isomerised to l-anisyl-idene-3-benzylindene (IX) when boiled with alkali.C:CHPh/\/\ IAB" C* C H, C,H, OMeI n some cases, however, both forms are stable towards boilingalkali, for instance, when R and R/ are phenyl and 2 : 4-dichloro-phenyl respectively; in others, the action of alkali brings about anequilibrium between the two forms, for instance, when R and R'are phenyl and p-tolyl.It is interesting to note that in two cases (where R=furyl, andR' = phenyl, or p-methoxyphenyl) it has been possible to isolatethe intermediate product (X) as well as the extreme forms (IV)and (V).Anthraquinme.s.-J.L. Simonsen44 has thrown more light onthe constitution of the natural colouring matter, marindone, whichwas known to yield 2-methylanthracene on distlillation with zincdust, and believed to be a trihydroxymethylanthraquinone.45 Thisview has now been confirmed, and it$ is found, further, that two ofthe hydroxy-groups must be in the ortheposition wibh respect tothe carbonyl groups of the anthraquinone nucleus, since treatmentwith methyl iodide and alkali only yielded a monomethyl ether,whilst two of the hydroxyl groups are probably in the 1 : 2-position,since morindone is a mordant dye resembling alizarin.These andother reasons lead to the belief that it has one of the two formulagiven, (I) being thought the more probable.44 T., 1918, 113, 766.45 A. G . Perkin and J. J. Hummel, ibid., 1894, 65, 851ORGANIC CHEMISTRY. 87The oxidation of alizarin (111) by pot,assium ferricyanide inalkaline solution is found to yield an acid having the probableformula (IV).*6CO OH co(111.) (N4Bemzan$hrome .-It has been shown previously that l-phenyl-naphthalene-2 : 3-dicarboxylic anhydride (I) can be converted intothe isomeric 3 : 4-benzofluolrenone-l-carboxylic acid (111) by theprolonged action of cold concent'rated sulphuric acid or by meansof aluminium chloride in benzene.The change can also be broughtabout by alkaline hydrolysis to the dicarboxylic acid (11) and sub-sequent treatment with cold sulphuric acid.In an attempt47 to hasten the formation of the end-product byvarying the conditions of the first-mentioned method of prepara-tion, l-phenylnaphthalene-2 : S-dicarboxylic anhydride was heatedwith concentrated sulphuric acid for three hours a t 1 5 5 O , whenbenzanthronecarboxylic acid (V) was formed, together with asulphonic acid, probably derived from 3 : 4-benzofluoranone-l-carb-oxylic acid. The reaction is an instance of intramolecular changeof a five-membered ring to the more stable six-membered ring.Benzanthronecarboxylic acid was prepared previously by thefusion of the compound (111) with potassium hydroxide, yielding46 R.Scholl and A. Zinke, Ber., 1918, 51, 1419 ; A,, 1919, i, 26.47 A. Schaarschmidt and E. Korten, ibid., 1074 ; A., i, 43388 ANNUAL REPORTS ON THE PROGKESS OF CHEMISTRY.the acid (IV), and treatment of this with cold concentratedsulphuric acid.(IV.)Whilst the acid (IV) is the sole product. of the fusion of theanhydride (111) with alkali hydroxide, the parent compound,3 : 4-benzofluorenone (VI), yields the salfs of bolth l-phenyl-naphthalene-2-carboxylic acid (VII) and o-a-naphthylbenzoic acid(VIII) under this treatment.48(VII.) (VIII.)Dehydrogemtion.-The dehydrogenation of acenaphthene withthe formation of decacyclene and fluopcyclene, which was con-clucted previously by heating a t 280--290°, can be effected moreconveniently by heating a mixture of the compound with litharget o 300-380° in a sealed tube.49 From the by-products of thereaction, a green hydrocarbon, C,,H,,, termed chlorene, has beenisolated.The method may prove to be of use in the dehydrogen-ation of other hydrocarbons.48 A. Schwschmidt and E. Georgoacopol, Ber., 1918,51, 1082 ; A . , i, 434.49 K. Dziewoiiski and S . Siiknarowski, ibid., 45 7 ; -4., i, 296ORGANIC CHEMISTRY. 89Hydrocyclic Compo uitds and Terpemes.Derivatives of cyc1oPropane.-A new mode of preparation ofcyclopropane derivatives has been discovered in the action ofo-halogenoacetophenones on certain 3-substitated coumarins in thepresence of sodium ethoxide.60CH*COPh/\I n this reaction, the substituent in the 3-position of the coumarinnucleus may be an acyl (acetyl, propicmyl, or benzoyl), a carboxy-alkyl, or the cyano-group.The constitution of the condensat'ionproduct is proved in the case of. 3-carbethoxycoumarin (I) byhydrolysis, when a dibasic acid (11) is produced, together withsalicylaldehyde (111) and phenacylmalonic acid (IV) .(11.1C,H,<OH CHo a8nd PhC10*CH,*CH(C02H),.(111.) (IV.1The formation of cycEopropane derivatives does not take placewhen the 3-substituent, R, is hydrogen or the phenyl group, or with4-carbethoxycoumarin. It thus appears to be confined tocoumarins containing the groups of acetoacetic, malonic, and cyano-acetic esters.The reaction has been carried out successfully withseveral aryl halogenomethyl ketones, but cannot be effected withchloroacetme.Derivatives of cycloEeaau o??e .-The influence of the position ofthe bromine atoms in a number of dibrominated cyclohexanoneson the behaviour towards aqueous potassium hydroxide has beenstudied with interesting resulte.61 I n the case of compoundsformed by the saturation by bromine of an ethylene linkingadjacent. to the carbonyl group, different results are obtained accord-ing as the carbon atom next to the carbonyl group is st&ached t o1919, i, 32.5o 0. Widman, Rer., 1018, 51, 533, 907, 1210; A., 1918, i, 347, 393;51.0. Wallach, Annulen, 1918, 414, 271 ; A . , i, 44090 ANNUAL REPOEtTS ON THE PROGRESS OF CHEMISTRY.hydrogen or to an alkyl group.formed ; thus, carvacrol from 3 : 4-dibromocarvomenthone.In the first case, phenols areCHMe/\CH, COCH, CHBr I 1\iCBrMe\/CHMe,In the second, fission of the ring takes place, with the formationof aliphatic ketonic acids containing the same number of carbonatoms ; thus, 1 : dibromocarvomenthone yields ~-ketc+isopropyl-heptoic acid.CMeBr COMe/ \CHBr CO/\/CH, C0,HUH, CH,CHI ICHM~, ~ H M ~ ,Where the bromine atoms are divided between the nucleus andthe side-chain, or are both in the side-chain, the results are sovarious that no generalisation can be made. The most valuableresults, however, are obtained when the bromine atoms areattached to the two carbon atoms adjacent to the carbonyl group,when pentacyclic a-hydroxycarboxylic acids result .62I n connexion with the elimination of halogen hydrides fromderivatives of terpenes, another investigation may be noted.Whilst all the alkaline reagents previously employed for theremoval of hydrogen chloride from nitrosochlorides have dis-advantages, it has now been found that pyridine in acetone solu-tion gives excellent resu1ts.mThe Wagner Rearrangement.-The conversion of borneol (1)-a substance of the camphor type-into camphene (11)-a sub-stance of the fenchone type--on dehydration, and the reversechange from the feiichone to the camphor type in the dehydrationof fenchyl alcohol (111) to a-fenchene (IV), has been explainedhitherto in two ways by the assumption of the intermediate form-62 0.Wallmh, Anmk~li., 1918, 414, 296 ; A . , i, 442.6s 0. Wdlach, ibid., 267 ; A., i, 439.Compare Ann. Report,1916, 116ORGANIC CHEMISTRY. 91ation on the one hand of a tricyclene, and on the other of a sub-stance containing a bivalent carbon atom. The formulae of theCH,*CMe--CH * OHCH2*C:H--C1Me, CH,*CH-CH,c1 11%. CH--C:C!H,--+ dMe, 1 1 1alternative hypothetical intermediate products resulting from thedehydration of borneol are as follows :Froin the first, camphene would result by fission of the markedlinking of the trimethylene ring, whilst in the case of the secondformula, rearrangement of the linkings would be necessary forthe change.Whilst in the case o f .secondary alcohols, such as borneol, thetwo explanations are possible, the occurrence of the Wagner re-arrangement in the dehydration of a tertiary alcohol could onlybe explained by the first assumption. It has now been foundh4t-hat the tertiary alcohols methylborneol (V) and methylf enchylalcohol (VI) both undergo this rearrangement t o some extent ondehydration, yielding the same mixture of hydrocarbons, fromwhich both camphor and fenchone are obtained on ozonisation.This result- can be explained by the assumption that both alcoholsyield as an intermediate product the tricyclene (VII), the tri-methylene ring of which ruptures in two of the three possible waysto yield a mixture of methylcamphene (VIII) and methyl-a-fhnchene (IX).Report, 1914, 119.64 L. Ruzi6ka, Helv.Chim. Acta, 1918, 1, 110 ; A., i, 398. Compare Awt92 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.S'pinuct:ne.--The liver oil of certain fishes belonging to theSpinacidx or Squalid=, a family of sharks, contiaim about 90 percent. of an unsaturated liquid hydrocarbon. This compound,termed spinacene by A. C. Chapman,55 has the formula C2,H4,and forms compounds with both three' and six molecular propor-tions of hydrogen chloride and nitrosyl chloride. Itl appears to herelated to the terpenes, arid yields a compound, CI0Hl8, probablya cydodihydroterpene, when distilled over sodium under 45 mm.pressure.A r o m t ic Co n~poiinds of Xi t r ogen .Coupliizg.-The mechanism of diazo-coupling continues to arousediscussion.An account of the views of K. H. Meyer, K . vonAuwers, and P. Karrer was given in a previous Report.56One of the arguments brought forward by the last author insupport of his view that the addition of diazo-salts to ainines takesplace at' t"he nitrogeii atom, was the supposed inability of di-n-butyl-and diisoamyl-aniline to couple without. the loss of ail alkyl grouh.56 T., 1917, 1-11, 5 6 ; 1918, 113, 458. Cornpure M. Tsujimoto, J . Itit?.Eng. Chem., 1916, 8, 889 ; 1917, 9, 1098 ; A., 1916, i, 786 ; 1918, i, 89.66 Ann. Report, 19 1.5, I 1593 ORGANIC CHEMISTRY.In so far as di-n-butylaniline is concerned, the experimental basisof the work appears to be faulty, for J . Reilly and W.J. Hickin-bottom 57 have now shown that di-n-butylaniline combines in quitea normal manner with diazotised snlphanilic acid, yielding 4-di-n-butylaminoazobenzene-4~-sulphonic acid,(C,H,)2N*CGII,*N,.CH~* S03H.0. Dimroth and collaborators 58 have investdgated the questionraised by von Auwers as to whether the O-azo-compounds obtain-able from phenols and certain enolic compounds are truly O-azo-ethers, R*N:N*OR/, or diazoiiiuin salts, RON( iN)*O*R/. F o r thispurpose, they have measured the electrical conductivity of severalmembers of the class obtained by the action of 4-benzoylamino-naphthalene- 1 -diazonium chloride or pacetylaminobenzenedi -azonium chloride on phenols of different degrees of acidity, andfind that the conductivity of the compounds of the first-mentionedsalt with picric acid (p=30*48) and dinitrophenol (p=22.0) is ofthe same order as that of the chloride ( p ~ 3 1 .3 7 ) in aqueousacetone. These compounds, theref me, react as diazonium salts insolution. On the other hand, t.he conductivity of the compoundswith acetyldibenzoylniethane ( p = 0.26) and pentlaniethylphenol( p = 0.41) is comparable with that of p-nitrobeiizeiiediazornethyiether (p=0*79), which is doubtless a true O-azo-ether.All the compounds prepared, however, whether from phenols ofstrongly or feebly acidic properties or from aliphatic enols, sufferfission on treatment, with ethereal hydrogen chloride, yielding thediazonium chloride and the original hydroxylic constituent. More-over, they couple with phenols and amines. Both reactions-fissionand coupling-take place less readily in the case of the derivativesof aliphatic enols.Attention may be directed here to a consideration of this problembased on the theory of addition of partly dissociated complexes, t owhich brief reference was made last year.59D.iasoimi.lzes.-Following on the preparation of acyl-p-phenylene-diazoimides by diazotisiiig acyl-p-phenylenediamines with liquidnitrous anhydrides in dry acetone,60 the formation of some iin-stable free diazoimines by the same method is recorded.Nitro-p-phenylenediamine (I) yields the diazoimine (11) , which, althoughitself unstable except in a freezing mixture. is converted into the5 7 F., 1918,113, 99.5 8 0. Dimroth, H.Leichtlin, and 0. Friedemann, Ber., 1917, 50, 3534;5@ Mrs. G. M. Robinson and R. Robinson, T., 1917, 111, 963 ; Ann. Report,8o Ann. Report, 1917, 115.A., i, 128.1917, 13494 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.stable 3-nitro-4-acetyl-pphenylene-ldiazo-4-imide (111) on acetyl-ation.NHI INAc(1.1 (11.1 (111.)Similar results were obtained with 2 : 6-dichloro-p-phenylene-diamine.61Pormyl- (and acety1)- methylaminobenzene-4-diazohydroxides canbe obtained from the corresponding methylacylanilines by nitra-tion, reduction, and treatment with nitrous anhydride in dryacetone.62NMeAc NMeAc NMeAcBromoalkylated Aromatic Amines.-When methylaniline andethylene dibromide are heated a t looo in the proportion of fourmolecules to one, the main reaction is the formation of diphenyl-dimethylethylenediamine,4PhNHMe + CH&r*CH,Br = PhMeN*CH,*CH,*NMePh +2PhNHMe,HBr,but even under these conditions a trace of methyl-/3-bromoethyl-aniline, NPhMe-CH,*(TH$r, is formed, whilstl the yield of thiscompound can be increased t o 35 per cent.by employing a largerproportion of ethylene dibromide in the condensation.63 Methyl-&bromoethylaniline is a very reactive compound, and can be sub-jected successfully to all the reactions characteristlic of tertiaryaromatic amines and aliphatic bromecompounds.Several compounds of a similar type have been prepared andtheir reactions studied. For the mostl part, these are without anyspecial' importance, but one is of some interest. By combiningmethyl-8-bromoethylaniline with ethylaniline, NN/-diphenyl-N-methyl-Nj-ethylethylenediamine, NMePh*CH,*CH,*NEtPh, results,and the dinitrosederivative of this when hydrolysed by means ofG.T. Morgan and D. A. Cleage, Z'., 1918,113, 588.62 G. T. Morgan and W. R. Grist, iM., 688.aa J. von Braun, K. Heider,andE. Muller, Ber., 1917, 50, 1637 ; 1918, 51,273, 737; A., i, 107, 269, 406ORGANIC CHEMISTRY. 95concentrated aqueous sodium hydrogen sulphite gives s-methyl-ethylethylenediamine, NHMe*CH,-CH,*NHEt, in good yield. Themethod appears to be of general application for the preparation ofalkylated ethylenediamines of the type NHR*CH,*CH,*NHR’.An&.-K. von Auwers64 discusses several cases where the con-densation of aromatic aldehydes with substituted phenylhydrazines,semicarbazide, and aromatic amines gives an isdable additive com-pound as a first product in place of the anhydro-compoundnormally obtained, for example, R*CH(OH)*NH*R’ instead ofR*CH:N*R’.Whilst it is very rarely possible tlo pass back fromthe anhydro-compound to the hydrate, the closely related com-pounds of the type R42H(OH)*NAcR can be prepared from manyanils of substituted salicylaldehydes.N-Acetyl-o-hydroxylaminobenza1dehyde.-Although o-hydroxyl-aminobenzaldehyde has not yet been isolated, owing to the readi-ness with which it, decomposes into its anhydride, anthranil,a method of preparatioii of its iY-acetyl derivative has now beendiscovered .65 When “ agnotobenzaldehyde,” the primary reductionproduct of o-nitrobenzaldehyde, is treated with acetic anhydride,it yields oinitrobenzaldehyde and N-acetyl-o-hydroxylaminobenz-aldehyde in good yield.On heating to 1 2 5 O , this compound suffersrearrangement, with the formation of acetylanthranilic acid,CHO C6H4*NAc* OH + CO2H*C6H4*NHAc,whilst on oxidation with a solution of bleaching powder it giveso-nitrosobenzaldehyde in good yield.IAromatic Compounds 6f Tin, Lead, and Silicon.The main products of the bromination of tin tetra-aryls aloneor in organic media, even under the most careful conditions, arethe tin diary1 dibromides. By employing pyridine as the solvent,however, the reaction can be stopped a t the first stage, giving thetin triaryl bromide in a yield of 90-95 per cent. of thetheore tical.66Like the tin trialkyl bromides,67 the tin triaryl bromides yieldan ethereal solution of the corresponding hydroxide when shakenwith ether and sodium hydroxide.84 Ber., 1917, 50, 1686; A., i, 193.66 E. Brtmberger, ;bid., 1918, 61, 613 ; A., i, 346.67 G.Griittner and E. Krause, $bid., 1917, 50, 1802 ; A ., i, 158.E:‘ Kmuse, ibid., 912 ; A., i, 41696 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY-The use of pyridine is equally advantageous in the conversion oflead tetra-aryls into lead triaryl bromides by nieans of bromine,nearly theoretical yields being obtained, whereas previously underthe most careful conditions the yield did not exceed 10 per cent.of the theoretical.68By the action of magnesium aryl haloids on lead trialkyl haloids,lead aryl trialkyls have been prepared.69Alk,PbCl+ ArMgCl -+ Alk3PbAr.The magnesium p-halogenophenyl bromides derived fromp-chlorobromobenzene and p-dibromobenzene react with silicontetrachloride, yielding trichloro-p-halogenophenylmonosila~~es,which give p-halogenophenyltrialkylmoiiosilanes when treated withmagnesium alkyl haloids.'OC6H,Br*SiC1, + C,H,Br*Si(Alk),.These, again, react with magnesium, and the products can beemployed in Grignard syntheses to give compounds containingsilicon and also lead or tin.The magnesium compound of p-bromo-phenyltriethylmonosilane reacts with lead trimethyl bromide,giving ptriethylsilyltrimethylplumbylbenzene, SiEt,*C,H,*PbMe,,and with tin triethyl bromide, giving p-triethylsilyltriethylstannyl-benzene, siEt,*@,H,*SnEh,.The p-halogenophenyltrialkylmono-silanes can also be employed in syntheses by Fittig's method; thus,p-chlorophenyltriethylmonosilane reacts with chloradiphenylarsiriein the presence of sodium, forming . y-diphenylarsyltriethylsilyl-benzene, SiEt,*C,H,-AsPh2.FRANK LEE PYMAN.PART III.-HETEROCPCLIC DIVISION.OWING to the continuance of the war, a certain amount of over-lapping has again been rendered necessary in the compilation ofthis Report. Certain papers published in foreign countries couldnot be dealt witlh last year, owing to the journals containing themnot having reached this country in time to secure insertion ofaccounts of the work before the Report went t o press. Wherethese papers seemed suitable for description, accounts of them have6 8 G.Gruttncr, Bcr., 1918, 51, 1298; A., 1919, i, 52.6 9 Gerhard and Gertrud Gruttner, ibid., 1293 ; A., 1919, i, 62.7O G. Griittner and E. Krause. Ber., 1917, 50, 1559 ; A . , i, 132ORGANIC CHEMISTRY. 97been inserted in the present Report, although technically theybelong to last year’s work.The general trend of the year’s work appears to have beentowards the study of natural products, mainly in the alkaloidgroup, and it is a hopeful sign that organic chemistry is once moreturning back to its original field and is showing a weakening inthe interest in purely synthetic research which a t one timethreatened to divorce it entirely from t,he naturally occurringmaterials.Tn this branch of chemistry there is lithle room for mucht lieoretical speculation, apart from constitutional problems, butattention may be directed to the suggestions which have been putforward with regard to the mechanism of the benzidine change.The investigations centdng about the connexion betweenchemical constitution and physiological action in the cocaine seriesare also of interest, as this problem is one of the mosti obscure thatis touched on by organic chemistry.For the rest, the paragraph headings will suffice to give an ideaof the contents of the Report..A Theory of certain, Intramoleculw Changes.1Robinson and Mrs.Robinson2 have put forward an hypothesiswith regard to the mechanism of a peculiar intramolecular reactionwhich has been studied by them, and since their views also coverthe mysterious case of the benzidine and semidine changes, theydeserve a fairly full description here.The authors assume as a basis the possibility of a partial dis-sociation of molecules, and when a molecule has undergone partialdissociation they t’erm it “ activated.” Let A-b-c-D representthe structure of a molecule such that b or c (or both) are atomscapable of displaying a higher valency during salt-formation.Thesalt is now supposed to pass into the activated condition by theabsorption of energy, and in these circumstances it may be repre-sented by the following scheme, in which the acid is omitted forthe sake of simplicity: A-b ... c-D. Now, if the new partialvalenciss shown in this scheme are conjugated with unsaturated.. . . . . . .1 In thie eonnexion it seems desirable to point out the advantages of sub-titles in the case of certain papers. This oommunication bears the title‘‘ A New Synthesis of Tetraphonylpyrrole,” and thus no clue is given to thefact thst it contains important theoretical considerations. * Mrs. Q. M. Robinson and R. Robinson, T., 1918,113, 639.REP.-VOL. XV. groups in A or D, the molecule may be represented3 by somethinglike (I) or (11):Assume, now, a further conjugation of partial valencies in eachcase. The result will be, in case I, that A and c will becomeunited, and if this be followed by the conversion of partial intocomplete dissociation a t the junction of b and c, the result willbe the formation of the new molecule b-A-c-D.In case 11,the result will be a union bet'ween A and D accompanied by aseparation of b and c, resulting as a whole in the formation ofthe new molecule b-A-D-c. It will be seen that the first casecorresponds with the semidine change, whilst the second (double)shift corresponds with the benzidine rearrangement.In practice, indole derivatives may be obtained from substitotedhydrazines in a series of steps, which are shown in a simplifiedform below :NHThe mechanism of this is representmeid on the Robinson hypothesisas follows :-CH CH- -CH C'H- ...........................11 ji + I I - , -C-NH.....NH-C- -C-NH.....NH-C-Paxtial dissociation. Conjugation and ring-formation.(JH ......................... CH-1 i C=NH NH=CFurther dissociation andconjugation.4CH -CH- -- *--- C--ONHH, NH,* - 8 2% +-- I I -C---- C -C=NH NH=CIIEnamic form. II ll Enimic form.SH-1: -( .-Indole derivative.Further confirmation of the hypothesis is found in the fact thata new synthesis of tetraphenylpyrrde has been based on it. WhenThe thickened lines stand for a normal valency plus a partial valencyORGANIC CHEMISTRY. 99t,he azine of deoxybenzoin is treated with dry hydrogen chloride a t180°, it is converted almost quantitatively into a tetraphenyl-pyrrole and ammonium chloride :Y'he Coumarin Group.Some investigations4 have been made with the object of deter-mining the conditions which govern the opening of the coumaran-one ring and the converse process of ring-formation from open-chain derivatives.I n the case of 1 : 4-dimethylcoumaranone, t'wo possible types ofopening reactions are known :The reaction marked (I) takes place when the coumaranone isallowed to oxidise spontaneously in air, whilst opening of the type(11) occurs under the influence of reagents such as hydroxylamine,which react with a carbonyl group.The first reaction is not suitable for the purpose of the investi-gation, since it appears to fail in the cases of more highly sub-stituted comaranones; but the second type has been utilised inorder to study the effect of substitution, and it has been shown thatsubstituents in the ortho- or para-position with respect to theoxygen atom have a weakening influence on the ring-stability,whilst meta-substituents have a strengthening effect.Turning tothe problem of ring-formation, it is found that substitution exertsmarked influence. When bn o-a-halogenacylphenol of the typeshown below is treated with alkali hydroxide, the reaction shownK. von Auwers and W. Muller, Ber., 1915, 50, 1149 ; A . , i, 37.E:100 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in the formulae takes place to a greater or less extent accordingthe nature of the radicle R.When the group A is a m-cresol nucleus and R is a propionylradicle, the corresponding coumaranone is the main product of thereaction, although some a-hydroxypropionylcresol is also formed.When A is derived from p-cresol and R is a butyryl group, thecondensation also yields the cournaranone ring ; 6-chloroacetyl-5-m-xylenol condenses with the greatest of ease to form 3:5-dimethyl-coumaranone.On the other hand, m-a-bromoisobutyryl-pcresolyields no cournaranone a t all, being converted into either 3:6-di-niethyl-1 : 4-benzopyrone or m-a-hydroxyisobutyryl-p-cresol.It has now been shown6 that when benzoacetodinitrile is con-densed with resorcinol under the influence of hydrogen chloride,the product is not 3-hydroxyflavone, but 7-hydroxy-4-phenyl-coumarin.A very simple method6 has been devised for the production ofhydroxycoumaranones, which may be illustrated by the specificcase of the dihydroxy-derivative. Phloroglucinol and chloroaceto-nitrile are dissolved in ether, and the solution is saturated withhydrogen chloride, by which means the hydrochloride of a keto-imide is precipitated.On boiling this product with water, it, ishydrolysed, and forms t,he required coumaranone :NH,HClOH OH C OH CO/\/\+ HO!,,!,/CH~A new type of coumarin derivative has been obtained7 in whicha cyclopropane ring forms part of the nucleus. For example, when3-acetylcoumarin and w-halogenacetophenones are treated withsodium ethoxide in cold alcoholic solution, two products result,,which have the structuresA Cl$?H, /\/\CH,ClNO1 IOH + CN--fHO(,!OH0\/CAc C0,EtCHBz<bH c, H ;OHA. Sonn, Ber., 1918,51, 821 ; A., i, 401.Idem, 1917,50, 1262, 1292 ; A., i, 31.0. Widmen, ibid., 1918,51, 533 ; A., i, 347ORGANIC CHEMISTRY. 101The compounds are not acted on by permanganate, as is theoriginal coumarin, owing to the fact that the ethylenic linkingdisappears from the coumarin ring in the course of their formation.The reaction appears t o be a general one.The Py-idirte Gro.zcp.A new general reaction for the synthesis of various pyridinepolycarboxylic acids has been worked out.* In its essentials, itconsists in the condensation of acetylpyruvic ester or its homo-lopes with compounds such as P-aminocrotonic ester.In the caseof ethyl acetylpyruvate and @-aminocrotonic ester, if the reactionis carried out at. Oo a pyridine derivative is formed:C0,Et C o p tC0,HI kO,H(3 I COO P O , H /\HO,C\/C*CO,EtcB2 / + CH*CO,Et = HCMe&O &Me Meb &MeNH,’ \/ N(1.1 (11.)When the mixture is allowed to become warm, however, otherreactions occur which reduce the almostt quantitative yield con-siderably.CMe(NH,):CH*CO,Et + H,O = COMe*CH,*CO,Et,+ NH,.COMe*CH,*CO*CO,Et+ NH,=COMe*CH,*C(:NH)*CO,Et + H,O.From the dimethylpyridinedicarboxylic acid (I) it is possible, byoxidation with permanganate, to produce a tetracarboxylic acid(11), so that the method lends itself to the production of a variedseries of compounds.Not only so, but, by distilling the acid (I)with calcium hydroxide, a 91 per cent. yield of 2 : 6-lutidine canbe obtained. This method appears to be the most convenient wayof preparing pure lutidine that has yet been devised.Some derivatives of the pyridine series have been describedwhich are formed by the action of aS-dichloroethyl ether on amino-compounds.g Thus, in the case of the reaction between afl-di-chloroethyl ether and ethyl P-aminocrotonate, the product isethyl 2 : 6-dimethyl-4-chloromethyl-l : 4-dihydropyridine-3 : 5-dicarb-oxylate.i, 183, 184.* 0.Mumm and H. Hiineke, Ber., 1917, 50, 1668; 1918, 51, 180; A . ,E. Bensry, ibid., 1918, 51, 567 A,, i, 360102 ANNUAL REPOB'I'S ON THE PROGRESS OF CHEMISTRY.The Relative Stability of Cyclic Bases.I n last year's Report10 it was pointed out that cyclic bases maybe converted into open-chain compound:; either by exhaustivemethylation or by the action of cyan.ogen bromide, and that thetwo reactions appeared to give similar results when used as tests ofthe stability of the rings in cyclic bases. It now appears11 thatdihydroindole forms an exception t o the general rule, as it is verystable in the Hofinaiiii reaction, but' is readily athacked bycyanogen bromide.With the latter reagenb, t.he reaction takesthe following form :The morpholiiie ring E appears t o rank along with tet?rahydr&so-quinoline and dihydrcisoquiiioline when tested with cyanogenbromide, whilst by the test of the HoEmaiin reaction it. standsmidway between the two.The theory of ring-closure has also been further investigated,13but the results appear to be of little general interest.A New Synthesis of Acridhe.When 1-aminoanthraquinone and o-chlorobenzaldehyde areallowed t o condense together in the presence of copper powder anddry sodium carbonate at, 220°, the reaction does not follow the0---3 :CH Ph /\A/\ I l l 1I / \1 A/\ ' I NH, (+PhCHO /'/'(('/ Not formed.\ 0\/\/\/ It0 \x,\/l\/~NHv\ I I I I 1 : \/\(\/ C H * / V0Formed in reaction.10 Ann.Report, 1917, 130.11 J. von Braun, Ber., 1918,51, 90; A., i, 185.1 2 J. von Braun and Z. Kohler, ibid., 265 : A., i, 268.1s R. Meyer and H. Ludera, AnnaEen, 1918,415, 29; A., i, 450ORQANlC CHEMISTRY. 103usual course with the production of a Schiff’s base, but, instead,o-l-anthraquinonylaminobenzaldehyde appears among the p r educts.The abnormal course of this reaction is attributed14 to a mutualinfluence between the carbonyl radicle and the adjacent amino-group, which leads to a repression of the basic function of thelatter. In order to test this view, other compounds were examined,in which the amino-group is similarly situated with regard to“negative” groups, and it has been shown that a nitro-group inthe ortho-position leads to an abnormal reaction, whilst nitro-groups in the meta- and para-positions seem to have no such effect-(The last result appears curious in view of the recognised influenceof certain para-substituents on one another.)From the o-nitroanilinobenzaldehydes produced by this reac-tion, nitroacridines can be obtained by means of concentratedsulphuric acid.In order to obtain acridine itself, iodobenzene ando-aminobenzaldehyde are boiled together in nitrobenzene withsodium carbonate and copper powder. The solvent is removedwith steam, and sulphuric acid is added:isoBraadein.When brazilin, C,,H,,O,, is oxidised, it yields the quinone,brazilein, Cl6Hl2O5, and by the action of mineral acids, the quinoneis convert,ed into a series of orange-red salts, which are termedisobrazilein salts.The constitut,ions provisionally assigned tothese substances are shown below :0CH ‘CH,\-// \ u H o oHBrazilin.0Brazilein.I* F. Mayer and B. Stein, Ber., 1917, 50, 1306 ; A., i, 36104 ANNUAL REPORTS ON THE F'IWGRESS OF CHEMTS'I'HY.S0,H3C CH,HO OHBrazilein hydrogen sulphate.Some of these isobrazilein salts have. now been syiithesised in thefollowing manner .15 Paean01 and veratraldehyde were condensedtogether, and the product, was reduced catalytically to the dihydro-derivative, dihydrobutein trimethyl ether. By prolonged boilingwith zinc chloride and a large excess of absolute formic acid, thetrimethyl ether gave rise to a product from which isobrazileinferrichloride trimethyl ether could be isolated.DemethylationOHwas then carried out by heat,ing the trimethyl ether salt withhydrochloric acid at 150° in a sealed tube, and the end-productshowed all the reactions of isobrazilein hydrochloride.The Imtin G T O U ~ .When the LV-sodium derivative of isatin is treated with methylo r ethyl chloroformate, the corresponding isatin-l-carboxylic esteris produced.16 I f these esters are boiled with water or treated withacids under certain conditions, they yield an acid which containsfour hydrogen atoms more than the parent l-carboxylic acid. Thisnew substance does notl give the indophenin reaction, and on ex-posure to air in alkaline solution it yields isatinic acid with ease.(During the reaction of decomposition, the methyl ester liberates16 H.G. Crabtree and R. Robinson, T., 1918,113, 859.lo G. Heller, Rev., 1918, 51, 424 ; A., i, 309ORGAN 1C CHEMISTRY. 105f ormsldehyde, and the ethyl ester produces acetaldehyde.)ently the acid thus formed has the st-ructureAppar-/\-CH*OH(?\//C(OH)*CO,HNHIn ordinary circuiristauces, it is not easy to reduce an indole t othe corresponding dihydro-compound, so t,hat the effect of intro-ducing a carbalkylvxy-group into t.he molecule is followed by amarked increase in reactivity on the part+ of the compound.The author draws a parallel bet'weeii the ease with which thisreduction takes place and the readiness with which enzyme actionoccurs, but it seems to be a somewhat fanciful view of the case.The new acid exhibits another curious reaction when it isoxidised with potassium dichromate and dilute sulphuric acid, forthe product is said to be a quiiiolinecarboxylic acid having thes tlrrnct ureIt' will be nbted that.this result corresponds with the accret'iolz ofan extra methylene group and the transformation of a five- i n ha six-membered ring. If the extra carbon atom can be success-fully accounted for, there seems to be little difficulty about theremainder of the change, since cases of the kind are already known,the most similar being thatl noted by Meiser,l7 wherein the pinacone(I) is converted into the pinacolin (11) on tmatment with diluteOH(1.1 (11.)sulphuric acid.of '' pseudo-enzymatic action " to account for the results.It seems scarcely necessary to resort to hypothesisThe Purine Group.A very full study of the oxidation of uric acid by means ofhydrogen peroxide 181 19 has produced interesting results.It appears1' W. Meiser, Ber., 1899, 32, 2054 ; A., 1899, i, 741.18. 1 9 C. S. Venable and F. J. Moore, J. Amer. Chem. SOC., 1917,39, 1750 ;C. S. Venable, ibid., 1918, 40, 1099; F. J. Moore and R. M. Thomw, ibid.,1120 ; A., i, 104, 409, 410.E106 ANNUAL REPORTS ON TEE PROGRESS OF CHEMISTRY.that under the conditions which were supposed to lead to theformation of tetracarbimide, this compound is not obtained, forthe main product is found to be cyanuric acid.It. seems likely,therefore, that the so-called tetracarbimide was really cyanuricacid.The reaction between hydrogen peroxide and uric acid is a com-plex one. I n weakly alkaline solutions at temperatures near looo,allantoin appears to be the first product, for it is produced in largequantities a t the beginning of the reaction and is accompaniedonly by minor proportions of carbonyldicarbamide. These twocompounds seem to be the result of two different' reactions, sincethey appear to be produced in arbitrary proportions. The furtherprogress of the reaction is marked by the amount of the carbonyl-dicarbamide remaining fairly constant, whilst the yield of allantoinrapidly decreases. Meanwhile, increasing amounts of cyanuricacid make their appearance up t o about 10 per cent. It is foundthat increasing alkalinity of the solution favours the formation ofcyanuric acid-even as much as 50 per cent.being formed undergood condit,ions-whilst the yields of allantoin and carbonyldi-carbamide are propor tionat ely diminished.It might be supposed that the cyanuric acid is formed from theallantoin, which is the primary product of the reaction, but thisappears to be negatived by the fact that under the same conditionsof experiment no cyanuric acid is formed directly from allantoin ;also, since the highest yield of carbonyldicarbamide observed canonly, assuming its complete conversion into cyanuric acid, bringthe percentage of the latter up to thirty, it will be seen that two-fifths of the cyanuric acid remains unaccounted for.It is evident that the reaction between hydrogen peroxide anduric acid takes a different course, according to the temperature andthe alkalinity of the solution in which it is carried out.Apparently an intermediate product occurs, as is shown by thefollowing evidence.The alkaline solution resulting from theoxidation was treated with manganese dioxide, whereby the excessof hydrogen peroxide was destroyed. After neutralisation, a 60per cent. yield was obtained of the salts of a dibasic acid,C4H505N3, which may possibly be hydrated allantoxanic acid,C4Hs04Ns,H20. This acid, when oxidised in acid solution bymeans of hydrogen peroxide, gives an 80 per cent. yield of cyanuricacid.Chromoisomerism.It will be recalled that when the salts of a base and an acidoccur in varieties exhibiting different colours the phenomenon haORGANIC CHEM ISTRI’.107been described by Hantzsch as chromoisornerism. The field hasproved a captivating one to those who delight to speculate on(( possible ” or “ theoretical ” structures for given molecules, but itseems time to protest against one halfpennyworth of practice tothis intolerable deal of theory, and to demand something morethan assertion in proof of the constitutional formulz which aredrawn up so lavishly.The latest example of this spirit is t o be found in a paper oniminovioluric acid.20 The free acid has been isolated in threeforms. With mineral acids, iminovioluric acid forms colourlesssalts; with alkalis or alkaline earths: pink or red salts are pro-duced. On these scanty data and on thestrength of absorption spectra curves the authors proceed to raisea mass of speculation, which becomes a t times detached fromreality.Four formulae are given as (‘ theoretically possible ” foriminovioluric acid, but a t least two other structures are equally“ theoretically possible,’’ and it seems curious not t o find them con-sidered also when stereoisomerides are included in the four actuallydealt with. Since- the metallic salts of iminovioluric acid haveabsorption spectra similar to those of the violurates, it is laid downthat the nitroso-group is modified and involved in the establish-ment of a “residual affinity ring.” There seems to be no evidencefor this, unless something definite can be adduced as to the con-stitution of the violurates.All that the spectra prove is thatprobably the exchange of the group *COO for t,he group *C(:NH)*produces no great alteration in the spectra.Again, i f the sodium salt is reduced with ferrous sulphate, adark blue powder can be obtained as a precipitate. It4 is statedthat it may be represented bySo much for practice.NH*CH--0 O----CH-NH co<I >c: KO~F~*O*F~LON:C< ‘C0,4H,O.LTH*C=I NH:’ ”. ..NF --C---NH/It may be, but. the evidence scarcely seems convincing.The Areca Nut Alkaloids.Our knowledge of the alkaloids yielded by the areca or betel n u thas advanced considerably, and the constitution of t.hese com-pounds seems to be almost established by the work of the pastyear.21 Apparently the nut is rich in related alkaloids, f o r the20 I.Lifschitz and L. Kritzmann, Ber., 1917, 50, 1719 ; A., i, 192.K. Hess and F. Leibbrandt, ibid., 1918, 51, 806 ; A., i, 401 ; K. Hens,ibid., 1004 ; ti., i, 403 ; K. Freudenberg, ibid., 978 ; A., i, 403.E” 108 ANNIJAL REPORTS ON THE PROGRESS OF CHEMISTRY.following have been detected in it, : arecaidine, arecoline (arecaidinemethyl ester), guvacine, arecaine (N-methylguvacine), andguvacoline (guvacine methyl ester).Arecaine has been definitely proved to be the guvacine N-methylderivative, since it is formed by the action of formaldehyde and€ormic acid on guvacine. Arecoline has already been prepared byesterifying arecaidine with methyl alcohol. Guvacoline has beenconverted into guvacine and vice versa by esterification orhydrolysis.Doubt still remains as to the exact constitution of these alkaloids,however, for although aremidine was synthesised some time ago,the method employed does not settle the structure of the end-pro-duct.Hess regards guvacine as 1 : 2 : 5 : 6-tetrahydropyridine-4-carboxylic acid, whilst Freudenberg believes t-hat the carboxylradicle occupies the 3-position. The evidence appears to inclinetoward the former view, since the reduction of guvacine yieldspiperidine-4-carboxylic acid.Two curious reactions may be mentioned in this mnnexion.When arecaine (N-methylguvacine) is boiled with alcoholichydrogen chloride, it loses its methyl group and yields the ethylester of guvacine.Again, guvacoline (guvacine methyl ester) issaid to yield arecaidine when its methiodide is hydrolysed. Thisimplies that arecaine and arecaidine are identical, alt.houghpossibly they may be stereoisomerides. Further work on the pointwill be of interest.Some negative evidence on the problem is obtained from theresults obtained in the course of the reduction of nicotinic acidderivatives.22 When trigonelline (I) is reduced with hydrogen inthe presence of platinum black and the product subjected to theaction of methyl iodide, the result is the formation of an N-methylderivative (11) which gives a platinichloride having the same melt-ing point as the platinichloride of arecaidine.The anrichlorideand the picrate of the new base, however, are not identical withthe corresponding arecaidine derivatives, It. seems certain, there-38 E. Winterstein and A. B. Weinhagen, Zeitsch. phy&i. Chem., 1917, 100,170; A,, i, 36OROA NIC CHEMISTKY. 109fore, from this and other evidence that aremidine cannot have theformula (11), although it may have a very similar structure.d Ekdoids of the Yomegrawt e Tree.The clearing up of this field really belonged to last year's Report,but owing t o war conditions it was impossible to take note of itin that place, and it is therefore dealt with here. It has nowbeen proved 23 that pelletierine is B-%piperidylpropaldehyde, or,in other words, the aldehyde of coniine:CH2/'\\/CH, CH,C'H, CH*CH,*CH,*CHO I INHCuriously enough, although pelletierine is a secondary base, it doesiiot react with nitrous acid.This behaviour has been attributedto the mutual influences of the nitrogen atom and the aldehydegroup, which, as can be seen from the formula, stand in the 1 :5-posit.ion with regard to each other.The pelletierine grotlp is suffering from the changes of nomen-clature which seem inseparable from alkaloidal research. Tanretisolated an inactive base which he termed isopelletieriiie, but thishas iiow been rechristened pelletierine by Hess and Eichel.Tanret's methylpelletierine has similarly been renamed methyliso-pelletierine.This ~ethyI.is:opelletierii~e has the formula C,H,,ON, and hasbeen shown to be a tertiary base containing a carbonyl radicle.When its hydrazone is heated with sodium ethoxide solution in asealed tube, 1-methylconiine is produced.This reaction limits thechoice of a formula for methylisopelletierine, since it. must have2>CHR, in which R is either the coiistitution CH2xCH,. N M-G'H,*CH,*CEiO or *CH,*CORIe or *COEt.The first two alternatives are ruled out, since they correspondrespectively wj t h methylpelletierine and a-l-methylpiperidyl-2-propan-&one, both of which are already known. Methyliso-pelletierine is therefore an ethyl ketone. A further change innomenclature seem justified in this case.The solution of the methylisopelletierine problem has broughtwith i t the determination of the conhydrine structure, for con-23 K. Hem and A.Eichel, Ber., 1917, 50, 1192, 1386 ; A., i, 33, 34..* C H ,--C110 ANNUAL REPORTS ON 'I'HE PROGRESS OF CHEMISTRY.hydrine can be converted into methylisopelletierine, and mud, inorder to make the reaction possible, be assumed to be a-Z-piperidyl-propyl alcohol.One point of interest in the stereochemical field is raised by thepelletierine derivatives. Originally i t was believed that thealkaloids of the pomegranate root- were optically active, but itseems to be now proved that they are entirely raceniic, no activesubstances being found. I n the great majority of cases, vitalsyntheses lead to the preponderance of one o r other antipode inthe product, but apparently the natural synthesis of pelletierineis a symmetrical process, or else the plant must, possess the powerof racemising the active alkaloid after its formation. Theracemisation of the free bases is apparently not likely to be spon-taneous, since they can be distilled without marked change intheir rotatory power.24Cocaine and i t s Allies.One of the most puzzling problems which confronts the in-vestigator is that which is concerned with the physiological actionof certain compounds.At the present time, the experimentalevidence is confusing and incomplete to such an extent that it isalmost impossible to draw any conclusions of value from it, andit is therefore of great interest to find that a systematic study ofeven a restricted class of compounds has been made.25It appeats probable that the physiological activity of cocaineitself is in some way connected with the presence of the acylatedhydroxyl group in the y-position with regard to the nitrogen atomin the ring, for the ,T-methylviayldiacetonealkamines of the struc-ture (I) have a pharmacological action very similar t o that oftropine, (II), wherein a similar grouping occurs :c H,*CH--CH, CH,--CH--CB,CH,*N bH-OH I CH,-N kH*OH I II 1 I ICH,*CH--CH, CI-T,---C H--CH,(I.1 (11.)It therefore remains t o be seen whether this characteristic isaffected when the acylated hydroxyl radicle in cocaine is trans-ferred to another point in the molecule while still retaining they-position with regard to the nitrogen atom.Cocaine This has now been done in the following manner.24 K. Hess and A.Eichel, Ber., 1918, 51, 741 ; A., i, 404.26 J. von Braun and E. Muller, ibid., 236 ; A., i, 233ORUANIC CHEMISTRY. 111(111) is converted by known methods into ecgonidine (anhydro-ecgonine), the ethyl ester of which has the structure (IV). B yreducing this first. with hydrogen and palladium, and subsequentlywith sodium and amyl alcohol, a new base, homotropine (V), isformed, which is then converted into the tropic acid derivative(VI). It is found that the niydriatic action of this substance isquite as powerful as that of cocaine itself.CH,*CH--C H*CO,Me CH,* CH-CH*CO,EtI 1 BMe t'H*OBz + I hMe b H +I I I 1UH,*CH--CH, CH,*CH-OH(111.) W.)C'R;CH'---CH*(JH,*OH UH;C!H-CHCH;OI I I I I NMe CH, + I NMe CH, c!OI I I IC'H; CH-CH,, CH,*CH---CH, C',H,O(V.) (VI.1This dearly indicates that the mydriatic effect of cocaine is notaffected by the transfer of the acylated hydroxyl radicle from onecarbon atom t.0 a fresh one, provided that.its y-position with regardto the nitrogen atom is retained.A different variation of the groups is shown in the compoundVII, wherein also the acylated hydroxyl radicle is situated in the./-position with respect to the nitrogen atom, although in this casethe hydroxyl group is completely detached from the ring:C H;CH-CH'C0,Et C H 2*C H-CH*CO,Et I AH bHCH,*CH--CKI N----------- CH;CH;CH<OBzI I I 1 / I CH;CH-CH;C H,(VII.) (77111.)The last substance has been obtained by a complicated series ofreactions which it, is unnecessary to describe, and it is found thatas a local anaesthetic it is quite as powerful as cocaine itself.Evidently it must be concluded that the essential feature of thetropine group from the pharmacological point of view lies in therelative positions of the nitrogen atom a.nd the hydrosyl radicle.for the case of the alkamines quoted above proves that the bridgedring structure of tropine is not, indispensable to the activity.I n the course of this investigation, a useful compound has beenisolated, which is termed eccaine and has the structure VIII.Itis more active than cocaine in its anzsthetic properties, and hasthe additional advantages of being non-toxic and sufficiently stableto render its sterilisation easy112 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.An examination has also been made20 of various compoundsderived from alkaloids of the cocaine group by demethylation ofthe nitrogen atom, and it has been found that they have consider-able activity, resembling cocaine in pharmacological action, andhaving the same advantages as eccaine in respect of stability andease of stmilisation.A very curious case27 has been discovered in the reductions oftropinone (I) and IC/-pelletierine (11).CH;CH-CH, CH, --CH-CH, 1 &Me bo C!H, .kMe b0CH,*UH -CH, CH,--C H--CH,(1.1 (11.)Reduction with hydriodic acid or electrolytically produces fromtropinone the physiologically active tmpine, whilst $-pelletierineyields by the same methods the physiologically inert isomethyl-granatoline. When the reduction is carried out with sodium andalcohol, the results are reversed.Tropinone gives physiolpgicallyinactive $-tropine, whilst, J/-pelletierine yields the active productmethylgranatoline.When tropiiie is heated with concentrated hydriodic acid andexcess of phosphonium iodide a t 200°, it is reduced to tropane.The same end-product is obtained when hydroscopolinc is similarlytreated, and from this it is deduced28 that scopoliiie and hydro-scopoline are tropane derivatives, hydroscopoline being regardedas a dihydroxytropane.I I I I IAllies of Be?-berine.A new system of nomenclature has been proposed for the coni-pounds of the berberine group,29 but as the formulae take up aconsiderable amount OF space, reference must be made t.0 theoriginal paper for details.An account is given of various attempts t o produce a compoundwhich has been termed epiberberine.The iiew substance isisomeric with herberine, and differs from i t inasmuch that themethyleiiedioxy- and dimethoxy-groups in herberine are trans-posed in epiberberine. A st.udy of some derivat,ives of berberineclosely allied to cryptopine3O has been made. but the paper doesnot' lend itself t o summarisation.26 Chernische Werke Grenzaeh, D.R.-P., 301139 ; A., i, 121.27 L. F. Werner, J . A ~ w . Chem. SOC., 1918, 40, 669 ; -4., i, 267.z* K. Hem, Ber., 1918,51, 1007 ; A., i, 404.9D W. H. Perltin, jun., T., 1918, 113, 491. 30 Ihid., 722ORGANIC CHEMISTRY. 113The Cinchona: dlkdoid~.Progress towards the complete synthesis of quinine is beingslowly made, and in t,he present year a'gap in the series of reac-tions has been bridged by the conversion of quinicine (quinotoxine)into quiniiie.31It will be recalled that when quinine and cinchonine are heatedwith dilute acetic acid, they are converted, respectively, intoquinotoxiiie and cinchotoxine.The reaction is believed ta consistin the conversion of a bridged ring into an unbridged one, as shownin the formulze---CH -....-- ~c: :cI(!! R*C:H;C-OH C: :c C0CH;R 6:\8H, /. :c \ /'./ \---NH---/ \--N-_-___- CH---I C'H, C: - I I I IIThe reverse chauge has now been accomplished in the followingmanner. Quinicine (quinotoxine), when treated with sodiumhypobromite. Furnishes S-brornoquinicine. Further treatmentwith alkali hydroxide yields the corresponding ketone, quininone,and when this is reduced with aluminium powder and sodiumethoxide solution, quinine is formed.The Poliowing fornukeindicate the nature of the process :-GO-CH,- -CO-CH,-R -CO-CH-K -CH(OH)-CH-RI -N- --t -N- ' + -NH- * - N B rIt is true that this step leaves many others still to be accom-plished, but it is none the less satisfactory to see even a smalladvance made in this difficult problem.With regard t'oi the other half of the quinine molecule, which isderived from quinolinc, some synthet.ic progress is being made inthe direction of the production of the cinchonic acids,32 but theresults up t o the present scarcely justify detailed description, asthey are mainly tentative.The complexity of the cinchona alkaloid problem becomes greaterwith increased research, owing to the number of possible isomerideswhich are obtained.Thus, when cinchonine is heated on a water-bath wit,h hydrobromic acid there are formed, in addition t ohydrobromocinchonidine, no fewer than five compounds, namely,ciachonigine, 6-cinchonine, npocinchonine, cinchoniline, and31 P. Babe and K. Kindler, Ber., 1918, 51, 466 : A ., i, 303.33 A. Kaufmann, &id., 116; A,, i, 187114 ANNUAL REPOR'I'S ON THE PROGRESS OF CHEMISTRY.cinchoniretine.33 It is assumed that cinchonigine and cinchonilinehave the constitution represented by (I), whilst apocinchonine ieregarded as possessing the structure (11), and on this basispossible to explain the fact that these three compoundscinchonine itself will yield the same hydrobromocinchonine, asare found to do in practice.it isandtheyCHISIe: C,,H,,N2: CH*OH(1.1 (11.1The action of hydrogen bromide, however, is not so simple a6might be anticipated, for, owing to the optical activity of the com-pounds, it is necessary to assume that the additive reaction ispreceded by certain stereoisomeric changes.From the complexityof the results of this simple reaction, it is possible to gauge thedifficulties of the cinchonine investigations.A study of the behaviour of a-hydroxycinchonine has led Gger 34to the conclusion that the compound has the constitution repre-sented by CH3*CH(OH)*[C,,Hl,N2(CH*OH)], but for the evidenceadduced by him, reference must be made to t,he original paper.The Ipecacuanha Alkaloids.This field appears to be now almost cleazed up.I n last year'sReport,35 a table was given showing the relations existing betweenthe various substances of importance. It was already known thatthe reduction of met.hylpsychotrine yielded both emetine andisoemetine, and it is now found that oxidation of either emetineor isoemetine leads t o the formation of psychotrine and rubr-emetine.36 This apparently establishes the fact that emetine andisoemetine are stereoisomerides, although the attempt t o convertone into the other has not. been successful. It has further beenshown that isoemetine is the methyl ether of isocephaeline. Acomplete table of relations between the various derivatives is givenin the paper, but need not be reproduced here.I n physiological action, the two stereoisomerides emetine andisoemetine differ from one another considerably, emetine beingmuch more toxic than isoemetine. Such differences are, of course,fairly common.83 E. Lhger, Compt. rend., 1918, 166, 76, 255, 460 ; A., i, 121, 182, 232.341bid., 166, 903; A., i, 304.36 Ann. Report, 1917, 139. 36 F. L. Pyman, T., 1918,113, 222ORGANIC CHEMISTRY. 115Car~zoeim amit Histidine.The constitution of carnosine is now placed beyond doubt, bothby indirect methods and by direct syntbesis.37 The choice of aformula for the compound was limited to 8-alanylhistidine (I) andhistidyl-P-alanine (11).The indirect evidence was obtained by eliminating the amiuo-radicle and then hydrolysing the product, with the result thatabout 70 per cent. of the theoretical yield of histidine was obtained.Obviously, had the formula I1 been the correct, one, no such effectcould have been produced, since the histidine molecule containsthe eliminated amino-group .Carnosine was then synthesised in the following manner. P-Iodo-propionyl chloride was allowed to acb on histidine, and the pro-duct was treated with ammonia, whereby the iodine atom is dis-placed by the amino-group.A convenient method of preparing histidine from red bloodcorpuscles has been described.%Ricinine.A certain amount of evidence has been brought forward59 toprove that ricinine is a glyoxaline derivative having the structureOn hydrolysis with dilute potassium carbonate, ricinine yields theparent acid, ricininic acid, which can be reduced with sodiumamalgam to a dihydro-derivative. This gives a coloration withferric chloride characteristic of glyoxalinecarboxylic acids. Notetrahydro-derivative was obtained, which also favours theglyoxaline hypothesis. On oxidation with chromic and sulphuricL. Baumann and T. Ingvaldsen, J . BioZ. Chem., 1918,35, 263 ; A., i, 464.H. M. Jones, ibid., 33, 429 ; A,, is 232.as B. B6tfchers Bw., 1918,51, 073 ; A., i, 304116 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.acids, ricininic acid yields methylamine, oxalic acid, and hydrogencyanide, thus behaving like the other glyoxaline derivative,histidine. Fuming hydrochloric acid degrades ricininic acid to apyridone derivative, the formula of which has been proved to beThe evideiice seems sufficient to shomw that riciiiiiie belongs to theglyolxaline groiip.Ha emin.Three papers on haemin40 were published last year too late foriiotice in the 1917 Report. I n past years, there has been a con-siderable amount of ingenuity spent on constructing f ormulze forhzmin, but it must be confessed that as yet we are without asure basis in the matter, since the authorities differ almost entirelyin tbeir views. It is clear that a good deal of slow accumulationof knowledge will have to take place before we are in a positionto lay down t-he true constitutlioii of lwmin, and the presentpapers represent a contribution t o that taskIt may be recalled that the hemin molecule contains twocarboxyl radicles, two imino-radicles, and an iron atom, in addi-tion to numerous other groups of no direct importance here.When the iron atom is replaced by its equivalent in hydrogen, weobtain hmatoporphorin.I f diazomethaiie is allowed t o act on hRmatoporphorin, methylation occurs readily, but no analogous reaction takes place withhzemin itself. This evidently indicates some connexion betweenthe presence or absence of the iron atom and the power of methyl-ation.Now if a hamin derivative, known as P-bromohzmin, isesterified wit.h ethyl alcohol, i h yields 8-bromoethylhzemin, andwhen diazomethane acts on the latter substance, B-methylethyl-haemin is formed. I n other words, the presence of the ethyl groupis no hindrance t o the further step of methylation. On the otherhand, if &chlorohzmin is allowed to react with diazomethane,8-chloromethylhzemin is produced, and on this compound diazo-methane produces no further effect. I n this instance, therefore,the introduction of the methyl group has inhibited further action.From this it follows that in esterificatioii with ethyl alcohol andin methylation by diazomethane, two different groups are beingattacked. Not only so, but the same difference is detected whenthe hzmin compound is esterified with ethyl alcohol and with40 W. Kuster, Zeitsch. phyiG001. Chem., 1917, 101, 25, 33, 43 ; A., i, 199, 200ORGANTC CHEMISTRY. 117methyl alcohol: in the one case diazoniethane reacts with theproduct, but in the case of the methyl ester there is no furthermethylation. From this evidence, Kuster deduces that one of thecarboxyl groups of haemin is closely related to an imino-radicle(and hence to the iron atom, since the, latter is supposed to beintimately connected in some may with the imino-group), and hesuggests that, the phenomena may be formulated somewhat, asbelow :An attempt to support this by furhher evidence was madein the following way. When methyl alcohol acts on h m i n ,methylhamin is formed. The action of ethyl alcohol on thiseffects the displacement of the methyl by the ethyl group, yieldingethylhzemin. On t?he other hand, the direct action of ethyl alcoholon haemin, since it involves the other carboxyl group, should yieldan isomeric ethylhamin. Hithert o, no such isomeric ethylhaeminshave been isolated.A. W. STEWART

ISSN:0365-6217    

DOI:10.1039/AR9181500048

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

ANALYTICAL CHEMISTRY.THE decrease in the number of papers which characterised thisbranch of chemistry last year has been still more pronouncedduring the past twelve months. As was t o be expected, there havebeen relatively few contributions from German sources, whilstAmerican journals have again been responsible for a large pro-portion of the published work.Owing to the intensified shortage of materials, further attentionhas been given to the recovery of expensive reagents after use inanalysis,l and to devising apparatus and methods for which cheaperor more available substances are required.For example, an alloy of about 11 per cent.. of platinum with89 per cent. of gold has been used as a substitute for platinum forchemical apparatus? and it has been shown that, manna can replaceglycerol in the titration of boric acid.3Physic& Methods.Attention was directed in last year's Report4 to certain sourcesof error in the methods of determining 'viscosity by means of thestandard instruments, and to some of the suggestions which havebeen made to overcome these drawbacks.To obviate the effectof variations in the pressure due to the height of the column ofliquid over the orifice, an apparatus has been constructed in whichthe liquid is driven a t a definite temperature through the openingby means of measured centrifugal force, and the viscosity is ex-pressed in terms of the acceleration due to gravity (g).5In this connexion, mention may also be made of a modifiedform of " mercurial viscosimeter " intended for volatile liquids.I n13. Blount, Amtyst, 1918,45, 119 ; A., ii, 174.0 I. L. B. van der Marck, Pham. WeekbM, 1918,55, 149.* L. E. Iles, A d @ , 1918, 45, 323; A., ii, 407.Ann. Report, 1917, 146.W. C. Cope, J . I d . Eng. Chern., 1917,9, 1046.Compare Ann.Report, 1917, 146.11ANALYTICAL CHEMISTRY. 119this instrument, an equal excess pressure is produced by means ofan attachment above and below the column of liquid.6There have been several further applications of the use of thespectroscope to analytical work. For example, a definite weightof a mineral containing a particular element is vaporised, and ascreen in which is a horizontal slit is made to travel vertically at,a measured velocity in front of the vapour.Froin the length oftime during which a given ray of the element remains visible, thequantity of that element may be calculated.7Another quantitative spect.roscopic method has been used for theestimation of rubidium and msium in plant ash. The potassium,rubidium, and caesium are separated as platinichlorides and con-verted into chlorides, and the solution is compared spectroscopic-ally with standard solutions of the chlorides of the same elementsprepared under the same conditions.8An accurate means of titrating the acidity of coloured solutionshas been based on the difference of the absorption spectra of certainindicators in acid and alkaline solutions. Equal quantities of anindicator are added to water and to the liquid under examination,and alkali is run in until the characteristic absorption band,observed with a pocket spectroscope, is seen in the same positionin each case.9The spectroscopic method affords a sensitive test.for boron, beingcapable of detecting 1 part in 10,000.10An optical method of estimating potassium and sodium has beenbased on the difference between the refractive indices of therespective chlorides in a 20 per cent. solution a t 25O, that of sodiumchloride being 1.36829, and that of potassium chloride 1.35992.Hence the relative proportion of the two salts in admixture maybe calculated from the refractive index of the solution.11It has also been shown that the refractive index may be usedas one of the optical measurements for identifying cinchonine,cinchonidine, quinine, and quinidine when separated in crystallineform from a mixture of the four alkaloids. The refractive indicesare determined in solutions of potassium mercuric iodide andglycerol, the optical refraction of which is known.12For the estimation of malic and tartaric acids in the presenceF.M. Lidetone, J . SOC. Chem. Id., 1918,37, 14811.A. B. P. Leme, Compt. rend., 1918,166, 465 ; A., ii, 172.A. Tingle, J . Amer. Chem. SOC., 1918, 40, 873 ; A., ii, 236.A. de Gramonf, Cmpt. Tend., 1918,166, 477 ; A,, ii, 173.8W. 0. Robinson, J . Id. Eng. Chem., 1918,10, 60; A,, ii, 132.l1 B. A. Shippy and Gc. H. BWOWB, J . AWT. Chern. SOC., 1918, 40, 186;la E. T. Wherry and E. Yenoveky, &id., 1063; A., ii, 330.A,, ii, 131120 ANN[TAL REPOB'I'S ON THE PROGRESS OF CHEMISTRY.of each other, advantage has been t.aken of the fact that theoptical rotation of Z-malic acid and of &tartaric acid is increasedby uranyl acetate, whereas the rotation of Z-malic acid is reversedby ammonium molybdate. By plotting the optical rotations ofeach acid in solutions up to 1 per cent., in one case activated withnranyl acetate and in the other with ammonium hsptamolybdate,two series of curves sloping in opposite directions are obtained.The points of intersection of each correlated pair of cuilres willshow the amount of tartaric acid on the abscissa and that of themalic acid on the ordinates.13An opt.ica1 method to which, of late years, iiicreasing attentionhas been given is that termed nephelometry, or the measurement.of the light reflected from a colloidal precipitate in suspension.Some of the principal technical applications of this method havebeen summarised, and the precautioiis necessary for obtainingtrustworthy results wit.h the iiephelometer have been described.The method is useful for the estimation of precipitates oflight colour, those of dark colour being more suitably measuredcolorimetrically .Substances which may conveniently be estimatedin t.his way include nitrogen, phosphorus, calcium, fats, andproteins .I4The term ' * nephelometric value '' is suggested as a convenientdescription of the amount of tarbidity produced by a givenquantity of a substance in a definite time in comparison with thatproduced by a standard substance under the same conditions.This value varies with the concentration of acid in the suspensionand alters with the change of turbidity on keeping, but for eachsubstance there is an optimum acid concentration which producesthe greatest turbidity with tlhe least change within a definiteperiod of time.15The detection of potassium by t,he flame test' may be renderedmuch more sensitive by coating a glass plate with a gelatin filmcontaining a mixture of two dyes, preferably Patent-blue andTartrazine, in specified proportions.As seen through this screen,the potassium flame appears bright red with a border of yellowish-green.A new application of a physical phenomenon as an indicator inacidimetry has been described. A measured quantity of a mixtureof vaseline oil and oleic acid is made to issue from a jet just belowthe surface of the acid liquid, and the number o€ drops is counted.Only rubidium gives a flame of similar colour.16J. J.WiUamm, J . A w r . Chem. SOC., 1918,4Q, 693 ; A., ii, 248.UP. A. Kober, J. Soc. Chem. Id., 1918,37, 75T.l6 F. A. Csonka, J . BWZ. Chem., 1918,4, 577 ; A., ii, 277.l6 A. Herzog, Chem. Zeit., 1918, a, €46 ; A., ii, 206ANALYTICA4L CHEMISTRY. 121On repeating this after successive additions of standard alkali, asudden increase in the number of drops will be observed whenneutrality is reached. The method thus depends on the measure-ment of the alteration in tension at the separation zone of twoimmiscible liquids .*7Gas Analysis.The catalytic absorption of hydrogen from a mixture of gasesby means of sodium oleate containing metallic nickel insuspension 18 cannot be recommended as an analytical process, since,apart from the difficulty of protecting the reagent from oxidation,the absorption of hydrogen is much too slow €or quantitativework .I9A method of estimatiiig benzene vapour in gases has been basedon the increase in volume which occurs when a measured quantityof the gas is introduced into a special apparatus containing benzenevapour. By determining the increase in volume which would havebeen produced by gas free from benzene, the necessary data for thecalculation are obtained.20 Since, as a general rule, the vapourpressure of a liquid is independent of the nature of an inert gasabove it, it.is possible t o estimate the amount of a vapour, suchas benzene, toluene, or xylene, in a gas, such as air, by determin-ing the difference between the pressure of the mixture and thatof the same gas completely saturated with the vapour. For thispurpose, two flasks are connected with a manometer, one of themcontaining the mixture, the pressure of which must be less thancorresponds wit<h complete saturation, and the other the gas byitself. Small bulbs containing the vapour are broken within eachflask, and from the difference between the readings the pressurecorresponding with the amount of vapour in the original mixturemay be found.21I n using the (‘ chlorale pipette ” 32 for the absorption of hydrogenfrom gaseous mixtures, it is essential that all carbon monoxideshould be removed, since otherwise the catalytic oxidation isretarded.% In the case of pure hydrogen, the “relative absorp-E.Bosshard and E. Fischli, Zeitsch. angew. Chem., 1915, 28, 365 ; A.,R. P. Anderson and M. H. Katz, J . Id. Eng. Chew., 1918, 10, 23 : A.,21 H. S. Davis, M. D. Davis, and D. G. MacGregor, ibid., 709, 712 ; A.,2z K. A. Hofmann, Ber., 1916, 49, 1660; A., 1916, ii, 636.28 K. A. Hofmann and H. Schibsted, ibid., 1663 ; A., 1916, ii, 637.l7 R. Dubrisay, Ann. Chim., 1918, [ix], 9, 26 ; A., ii, 368.1915, ii, 788.ii, 124.ii, 410, 411.2o R. P. Anderson, ibid., 26 ; A., ii, 84122 ANNUAL BEPORTS ON THE PROGRESS OF CHEMISTRY.tion velocity” is fairly constant, or increases slowly until half ofthe gas has been absorbed, whilst traces of carbon monoxide causea rapid reduction in the rate of absorption.Hence, by using astandardised pipette and constructing a curve showing the ratesof absorption up to this point (half-volume) with different minutequantities of carbon monoxide, it is possible to estimate the pro-portion of the latter in the gas.24To obtain trustworthy results when using the Rayleigh interfero-meter in gas analysis, the gas chamber should be a t least 1 metrein length, the gases compared must be a t the same temperatureand free from moisture, and the refractive index must be deter-mined with great accuracy.25Ag&zcltural Analysis.The dearth of potassium salts, mainly due t90 the stoppage ofthe German supplies, has caused attention to be directed to otherpossible sources of supply, such as felspar, dust from cement kilns,siliceous rocks, and the like. Hence the necessity for the accurateestimation of potassium is of paramount importance, and thevarious methods hitherto proposed have been subjected to criticalexamination during the past year.There are little differences in the methods used for the extrac-tion of soluble potassium salts from various materials, but in thecase of substances, such as siliceous rocks, from which the potassiumcannot be extracted by the citric acid process, various processeshave been proposed.Trustworthy results are obtained by decom-posing the material with pure hydrofluoric and sulphuric acids.After removal of iron, aluminium, manganese, and sulphuric acid,the alkalis are converted into chlorides, and the potassium isseparated by the platinichloride or perchlorate method.26 Oneobjection to the hydrofluoric acid method is that very thoroughwashing is required t o remove all potassium from the bariumsulphate precipitate.27 The Lawrence-Smith method, in which thematerial is heated with a mixture of calcium carbonate andammonium chloride, then digested with water, freed from calcium,and the alkalis estimated in the filtrate, has the advantages ofsimplicity and of requiring reagents more readily obtainable thanhydrofluoric acid in the pure condition, but’, on the other hand,24 K.A. Hofmann and H. Schibstsd, Ber., 1918, 51, 837 ; A., ii, 329.86 F.M. Seibert and W. C. Hrtrpster, U.S. Bureau of Mines, Techn. Paper,26 B. Blount, Aizalyst, 1918, 43, 117 ; A., ii, 174.27 G. N. Huntly, ibid., 1918, 43, 122.No. 185, 1918 ; A., ii, 367ANALYTICAL CHEMISTRY. 123it leaves about 1 per cent. of potassium unattacked, and a secondtreatment is required t o decompose this.% If, however, the heating is continued for two hours a t 170°, the decomposition is com-plete in one operation.29 For the estimation of the potassium, theperchlorate method is quite trustworthy, although it is usuallyregarded as less accurate than the platinichloride method. Thecobaltinitrite method is fairly satisfactory for materials contain-ing 1 to 2 per cent3. of potassium, but is liable to be erratic, andmay yield too low results.30 A gravimetric modification of themethod which is suitable for the estimation of potassium in soils,f ertilisers, etc., has been devised.31 The method of calculating theproportions of potassium and sodium froin the amount of chlorinein a weighed mixture of the chlorides has the drawbacks of mostindirect methods. If the McLean-Van Slyke method is used forestimating the chlorine, the probable error in the amount of sodiumincreases with the decrease in the proportion of sodium topotassium, and is usually about 1 per cent..32 I n another indirectmethod, the potassium is calculated from the amount of platinumin the potassium platinichloride .33The methods of estimating phosphoric acid in fertilisers, plantash, etc., have been subjected to further critical examinationduring the year, and several new methods have been devised.34 I none of t-hese methods, intermediate precipitation of phosphoric acidas molybdate is avoided.The ash is dissolved in acetic acid, thecalcium separated as oxalate, and the phosphoric acid precipitatedas magnesium ammonium phosphate, citric acid being used to pre-vent the precipitation of iron add aluminium .35 An analogousmethod has been recommended for the estimation of phosphoricacid in superphosphates.36 Anot.her method is to precipitate thephosphoric acid as a basic compound of mercury by the additionof yellow mercuric oxide, t.0 decompose the latter with sodiumsulphide, and to precipitate the phosphoric acid as ammoniummagnesium phosphate.37A precipitate of constaut composition, MgNH,PO,, may be98 G.N. Huntly, loc. cit.20 P. Wenger and E. Brange, won. Sci., 1918, [iv], 8, T., 97 ; A . , ii, 275.3O E. M. Hawkins, Analyst, 1918, 48, 121.31 C. V. Garole and V. Braun, &4nn. Fals;f., 1917, 10, 672 ; A., ii, 131.32 F. H. McCrudden and C. S. Sargent, J . Biol. Chem., 1918, 33, 236 ;38 T. Steel, Analyst, 1918, 43, 348 ; A., ii, 407.34 Compare Ann. Repmt, 1917, 151.36 J. Grossfeld, Zeitsch. and. Chem., 1918, 57, 28; A., ii, 129.36 G. Vortmann, Zeitsch. anal. Cham., 1917, 58, 465 ; A., ii, 129.37 G. Vortmann, loc. cit.A., ii, 82.See alsoD. Balareff, Zeitsch. anorg. Chem., 1918, 103, 73 ; A., ii, 332124 ANNUAL REPOKl’S ON THE PROGRESS OF CHEMISTRY.obtained by causing ammonia to diffuse slowly into the acid solu-tion containing magnesia and phosphoric acid in the presence ofammonium chloride.I n Schultze’s method of adding ammonia tothe hot solution containing ammonium chloride, the precipitatewhich separates on cooling is not pure. A second solution andreprecipitation gives more trustworthy results.38The presence of ammonia interferes with the accuracy of theresults obtained by titrating the phosphomolybdic precipitate withstandard alkali when phenolphthalein is used as indicator. Thismay be obviated by precipitating the phosphoric acid as potassiumphosphomolybdate.3~ By adding a specified amouiit of ammoniumnitrate to the solution before the addition of the ammoniummolybdate, the precipitate will contain phosphoric oxide andammonia in proportions corresponding with the triammonium com-pound, and the ammonia may be estimated by distillation withalkali and calculated into the corresponding amouzit of phosphoricacid .40A method of estimating inositd-phosphoric acids in feeding-stuff sand the like has been described.It seems probable that. inositol-pentaphosphoric acid, C,H,( OH) ( R2PO4),, is the only inositol-phosphoric acid in the common feeding-stuEs.41Ammonia i n soil extracts may be estimated by Folin’s aerationmethod, the extract being mixed with magnesium oxide and aeratedin the cold for three hours. The ammonia is absorbed in acidtowers, and the acid subsequently distilled with alkali. Beforeestimating nitric nitrogen in the extract, it is necessary to eliminateproteins, which yield ammonid when heated with sodium hydr-oxide.For this purpose, the liquid is treated with copper hydr-oxide and filtered, and the nitric nitrogen in the filtrate estimatedby reduction with Devarda’s alloy and distillation of the amm0nia.4~A study of soil acidity and the hydrolytic ratio in soils hasshown that there appears to be a definite relationship between theproportion of iron and aluminium compounds in a soil and itsreaction towards litmus paper.CaO : (Fe,O, + Al,O,)was found to exceed 1:1*3, and the amount of lime required t oneutralise such a soil may be found by calculating the quantityrequired to be added to the acid-soluble calcium oxide t o bring theratio to 1 : 1.3.43** D.Balareff, Zeitach. awg. Chem., 1918, 104, 63 ; A., ii, 406.1 9 H. Heidenhain, J . Ind. Ens. Chem., 1?18,14, 436; A., ii, 273.4o J. Clarens, Compt. r e d . , 1918, 166, 269; A., ii, 128.(1 J. B. Rather, J . Amr. Chem. SOC., 1918, 40, 623; A., i, 212.IB B. S. Davisson, J. Id. Eng. Chm., 1918,10, 600 ; A., u, 370.48 C. H. Spurway, J. Agric. Res., 1917, 11, 659 ; A., i, 162.In acid soils, the ratiANAL Y TI C AL C HER1 IST R Y. 125Organic Analysis.Qualitative .-There have been few additions during the year t othe methods of identifying groups of organic compounds. Theprincipal new general method of examinat-ion has been based onthe use of ail acetic acid solution of chromic acid as an oxidisingagent, which under specified conditions oxidises organic compoundswith the liberation of acetone and aldehydes. These products mayhe separated by distillation and identified by conversion into theirp-iiitrophenylhydrazones, which are relatively insoluble.By meansof this test, methylpentoses, such as rhamnose, may be identifiedin the presence of pent~ses.4*It has been shown that the colour reaction given by lactic acidwith thiophen and sulphuric acid is due to the formation of form-aldehyde, and a sensitive test for aldehydes has been based on thisfact,. The shade of the red coloration given by aldehydes on treat-ment with an alcoholic solution of thiophen in the presence of con-centrated sulphuric acid varies with the particular aldehyde. Thetest is capable of detecting 1 part of formaldehyde in 100,000.45The guaiacol in guaiacol carbonate may be detected by giving acherry-red coloration with ferric chloride and formaldehyde in thepresence of sulphuric acid.Conversely, guaiacol carbonate may beused as a sensitive reagent for aldehydes in ethyl ether, beingcapable of detecting 1 part in 300,000.46Attention is still being given to the sensitiveness of variousmethods of detecting hydrocyanic acid.47 The only really dis-tinctive test is that based on the formation of ferrocyanides, otherreact.ions being less trustworthy, since they are also produced byother substances. In comparative tests with solutions of purehydrocyanic acid, it was found that the following amounts ofcyanogen (in mg. per litre) could be detected by the variousmethods : ferrocyanide 2, thiocyanate 0.1, picric acid 1,guaiacum 0.004, phenolphthalein 0.05, silver 0.03, and iodine-starch 0.1 mg.48Formjc acid may be detected by heating the liquid with a con-centrated solution of sodium hydrogen sulphite, and, after cool-ing, pouring a dilute solution of sodium nitroprusside on to thesurface.In the presence of formic acid, sodium hyposulphite is44 A. Windaw, Zeitsch. physiol. Chem., 1917,100, 167 ; A., ii, 22.46 W. R. Fearon, Biochem. J., 1918,12, 179 ; A., ii, 462.46 C?. Maue, Pharm. Zeit., 1918,68, 255; A., ii, 336.compare Ann. Report, 1916, 173 ; 1917, 153.I. M. Kolthoff, Zei-tsch. anal. Ciaem., 1918, 57, 1 ; A., ii, 138126 ANNUAL REPOKTS OK THE PROGRESS OF CHEMISTSY.formed from the sodium hydrogen sulphite, and this reacts withthe nitroprusside to produce a blue or green ring, due to the com-pound Na4Fe2(CN),, whilst hydrocyanic acid is liberated.49A test for tartrates has been based on the solubility of cuprichydroxide in alkaline solutions of alkali tartrates.Although, byusing potassium ferrocyanide for the detection of copper in thefiltrate, this test is capable of detecting 0.2 milligram of tartrate,it cannot be regarded as distinctive, since other salts, includingarsenites, borates, and phosphates, give a positive result in theabsence of tartrates, whilst other compounds, including chromates,nitrites, and acetates, interfere with the reaction.%A distinctive reaction for acetylcarbiiiol is produced by boilingits soluteion with o-aminobeiizaldehydel, cooling the liquid, andtreating it.successively with acid and with excess of sodiumhydrogen carbonate. A blue fluorescence is obtained, and, onextracting the liquid with ether and evaporating the extract,3-hydroxy-2-methylquinoline is leftl as a white residue, which givesa red coloration with an alcoholic solution of ferric chloride.51The formation of a yellow condensation productq (m. p. 208O)with cinnamaldehyde enables malonic acid to be detected in thepresence of oxalic, succinic, and citric acids. The drawback of thetest is that about ten hours are required t o form the condensationproduct, cinnamylidenemalonic acid .52A sensitive reaction for mercury fulminate depends on the factthatl it yields pararosauiline by heating with phenylhydrazine,subsequently diluting the liquid with alcohol, and adding adilute acid.53Ergotinine may be detected in an alcoholic solution containing1 part in 1,240,000 by means of the potassium mercuric iodidereagent for alkaloids.Tanret’s test for this alkaloid is renderedtwice as sensitive by adding a trace oi hydrogen peroxide asoxidising agent to the sulphuric acid.54&zcantitative.-It is perhaps in this division of analytical chem-istry more than in any other that the reduced amount of researchis indicated. There have been very few contributions to themethods of elementary analysis. In using cerium dioxide andcupric oxide as a catalyst in association with a mixture of leadperoxide and minium for a series of combustions of substancesL. J.Curtman, A. Lewis, and B. R. Harris, J . Amer. Chem. SOC., 1917,4s E. Comanducci, Boll. Chim. farm., 1918, 57, 101 ; A., ii, 248.39, 2623 ; A., ii, 87.61 0. Baudisch, Biochem. Zeikch., 1918, 89, 279 ; A., ii, 412.52 J. Bougoult, Ann. Chim. anal., 1918, 23, 164; A., ii, 413.63 A. Langhans, Zeitsch. angew. Chem., 1918, 31, i, 161 ; A., ii, 414.L. Wolter, Chem. Zeit., 1918, 42, 446 ; A., ii, 414ANALYTICAL CHEMISTRY. 127containing nitrogen, it is essential to ensure complete decomposi-tion of cupric nitrate after each combustion.s5I n estimating nitrogen by Kjeldahl's method, the results are toolow in the case of certain compounds, such as pyridine, piperidine,quinoline, alld sometimes nicotine, possibly owing to the formationof sulphonic derivatives.To obtain accurate results for pyridineby the Arnold-Gunning modification, the heating should be con-tinued for several hours after the solution has become clear."6 Theresults obtained by Kjeldahl's met-hod are too low when the decom-position has been effected by means of sulphuric acid and mercury,and to obviate this it is necessary to add zinc dust or pot'assiumsulphide, followed by zinc turnings,. prior t o the distillation of theammonia .57A modification of DenigSs's colorimetric method of estimatingmethyl alcohol has been described in which the liquid is oxidisedby means of potassium permanganate, and the resulting form-aldehyde is estimated by means of Schiff's reagent (magentadecolorised with sulphurous acid) under the same conditions asstandard solutions of f ormaldehyde.58A method of estimating formic acid has been based on its oxida-tion by means of chromic acid and measurement of the volumeof carbon dioxide evolved in the reaction.Carbonates andoxalates, if present, are previously precipitated by means of calciumchloride, whilst acetates are not oxidised by chromic acid.59 Themethods of estimating the lower aliphatJc acids have been criticallyexamined, and a new method of separating acetic, propionic, andbutyric acids has been based on the fact that light petroleum (b. p.150° t o 300O) will extract most of the butyric acid and some ofthe propionic acid from the solution after saturation with calciumchloride and the addition of a small amount of potassium chloride.The acidity of the original solution and of the petroleum fraction,and the weight of sodium salts, dried a t 200°, obtained from bothliquids, give the data for the calculation.60 Butyric acid gives ared coloration when treated with hydrogen peroxide, ferrousammonium sulphate, and sulphuric acid, and then with sodiumhydroxide solution, sodium nitroprusside, and a slight excess ofacetic acid.This colour reaction has been made the basis of acolorimetric method of estimating butyric acid .61H. L. Fisher and A. H. Wright, J . Amer. Chent. Soc., 1918, B, 868.66 H. C. Brill and F. Agcaoili, Philippine J . Sci., 1917, I ~ A , 261 ; A., ii, 172.67 E. Sdm and S. Prager, Chem. Zeit., 1918, 42, 104 ; A., ii, 173.68 T.von Fellenberg, Biochem. Zeitsch., 1918, 85, 45; A., ii, 177.F. Tsiropinas, J . Ind. Eng. Chem., 191 7 , 9, 11 10 ; A,, ii, 137.6o R. D. Crowell, J . Amer. Chem. SOC., 1918, 40, 453 ; A., ii, 137.6L G. DenigBs, Ann. Chiin. anal., 1918, 23, 27 ; A., ii, 138128 ANNUAL REPORrS ON THE PLtOCfRESS OF CHEMISTRY.For the separation of oxalic acid from tartaric acid, the solutionis treated with a sufficient quantity of boric acid to prevent theprecipitation of calcium tartrate, and t.he oxalic acid precipitatedas calcium oxalate. The precipitate is washed and ignited, andthe resulting calcium oxide titrated with standard hydrochloricacid.62A comparative study of hhe methods of estimating acetone hasshown that Messenger’s method, which depends on the formationof iodof o m , gives incorrect results, whilst, no improvement iseffected by substituting arsenious acid for thiosulphate in thetitration.Kebler‘s modification of Robineau and Rollin’s method 63has been found the most t r u s t w ~ r t h y . ~ ~The work done in connexion with the subject of oils and fatshas been mainly concerned with the characteristics of individualfats, and few new methods of analysis have been introduced. Forexample, the composition of butter fat. has been once more in-vestigated by modern methods, including esterificatian, with resultsdiffering considerably from those previously recorded.65The measurement. of the optical dispersion of oils from ananalytical point of view has been studied, and it has been foundthat most of the common oils have very similar dispersions (0.0186to 0.0207), with the except.ion of coconut oil (0.0167) and tungoil (0*0371).66A method of detecting foreign fats in butter has been based ona fractionation of the glycerides by treatment with a mixture oftwo solvents (for example, alcohol and ether), one of which is morevolatile and dissolves fat more readily than the other.A currentof air is passed through the solution to evaporate the more volatilesolvent, and the less readily soluble glycerides which separate a t acertain stage during the evaporation are examined.67Twitchell’s method of estimating resin in soap is not applicableto resins other than colophony, and has the drawback that.it causespure fatty acids to show an apparent resin content. These objec-tions are obviated by a method based on the fact that nitratedresins are insoluble in light petroleum, whilst the fatty acids afterthe nitration may be quantitatively separated from the solution.66In estimating citral by Hiltner’s colorimetric method, certain62 A. Bau, Chem. Zeit., 1918, 42, 425 ; A., ii, 412.6s J. Amer. Chem. Soc., 1897, 19, 316; A., 1898, ii, 56.6c A. J. Field, J . Id. Eng. Chem., 1928, 10, 652; A., ii, 377.6s E. B. Holland and J. P. Buakley, jm., J . Aqric. Rea., 1918, 12, 719 ;A, ii, 250.P. J. Fryer asd F. E. Weston, AmZy&, 1918,443, 311.67 A. Seidenberg, J . Ind. Eng. Chem., 1918, 10, 627.s8V. Fortini, Anna& Chh. A s . , 1918, 9, 102ANALYTICAL CHEMISTRY. I29kinds of orange and lemon oils give a blue or green colorationinstead of the usual yellow tint when treated with m-phenylene-diamine hydrochloride. This may be prevented by adding oxalicacid to the reagent.69Several additions have been made to the methods of sugaranalysis.For the estimation of laevulose in the presence of: aldoses,the clarified solntion is inverted by the Clerget -Herzfeld method,cooled, and treated with bromine in a proportion correspondingwith the amount of aldoses. Only the aldoses are osidised, andthe lzevulose may siibsequently be estimated by determining it5reducing power.;o A modification of Bougault’s iodometricmethod 71 is described iii xhich a solution containing sodium phos-phate and hydroxide takes the place of the sodium carbonatesolution .72Another iodometric method of estimating dextrose consists intreating t.he solution with about twice the amount of standardiodine solution required to oxidise the dextrose to gluconic acid.C,H,,O, + I, +- 3NaOH = 2NaI -+ 2H,O + ITO*CH~*[CH*OH],*CO,Na,and then with an excess of sodium hydroxide.After twelve totwenty minutes, the solution is made slightly acid and the excessof iodine titrated. Ketoses and sucrose do not affect the results,and the method may therefore be used for estimating aldose. inthe presence of other sugare.73The proportion of lactose in arlmixtnre with siiclose axid invert-sugar may be calcnlated from the determination of the polarisatiouand reducing power of the mixture under standard conditions bymeans of an empirical formula constructed from data obtainedwith mixtures of the pure sugars.74A method of estimating phenol in the presence of the threecresols is based on the determiiiat-ion of the specific gravity andsolidifying point of the mixture, the necessary data €or the equa-tion having been obtained empirically from the results given bymixtures of the pure ~ubst~ances.76The drawback of Dowzard’s colorimetric inethocl of estimatingbrucine in presence of strychnine7c is that the coloration fades withvarying velocity.The method may be rendered more trustworthyC. E. Parker and R. S. Hiltner, J . I d . Eng. Chein., isis, 10, 608 ;A., ii, 377.7 O Herzfeld and Lenart, Zentr. Zuckerind., 1918, 88, 227.71 Compare Ann.Report, 1917, 159.H. Colin and 0. Lidvin, Bull. SOC. chim., 1918, [iv], 23, 403; A., ii, 461.R. Willstiitter and G. Schudel, Ber., 1918, 31, 780 ; A., ii, 337.74 J. Grossfeld, Zeitsch. Nahr. Glenmm., 1918, 35, 249 ; A., ii, 337.‘ti G. W. Knight, C. T. Lincoln, G. Formanek and H. L. Follett, J . Id.REP.-VOL. XV. B.Eng. Chem., 1918, 10, 9 ; A., ii, 84. 76 P., 1902, 18, 220180 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.by using a mixture of concentrated nitric and 20 per cent.sulphuric acids, and adding a saturated solution of potassiumchlorate immediately after the reaction.77Theobromine may conveniently be estimated by converting i t intoits periodide, C,H8O,N*,HI,I, and titrating the excess of iodine.The method is applicable in the presence of sodium acetate orsalicyla t43.78Pyridine or pyridine bases in ammonium salts or ammonia solu-tion may be estimated by precipitation with iodine in excess froma solution acidified with sulphuric acid.The excess of iodine isremoved by means of thiosulphate, and the periodides are titratedwith standard alkali, first with methyl-orange and then withphenolphthalein a8 indicator, The amount, of pyridine sulphateis calculated from the difference between the two titrations. Thesensitiveness of the method and completeness of the precipitationare increased by adding sodium chloride to the solution.79Abnormal results are sometimes obtained by Sorensen’s methodof formaldehyde titration for amino-acids, polypeptides, etc.Thishas been shown to be usually due to the presence of an imino-group, which is not converted by formaldehyde into a neutralgroup, as in the case of simple amino-acids, but into a group whichis still somewhat basic, and so causes too low results.80Inorganic Analysis.Qualitative .-Further applications of the use of textile fibresimpregnated with reagents in microscopical qualitative analysishave been devised.81 It has been shown that the difficulties whichattend the use of test papers are obviated when a single test’ fibreis used. For example, a fibre of turmeric viscose silk is a sensitivereagent for boric acid, being capable of detecting 0.000025 milli-gram of boron, whilst wool fibres saturated with zinc sulphide aresuitable for the detection of traces of copper (O*UOl milligram) andother heavy metals.82A test for iodides in the presence of cyanides has been based onthe precipitation of the cyanide by means of cobalt, nitrate, and7 7 A.Wtiber, Zeitsch. angew. Chem., 1918,31, i, 124 ; A., ii, 339.W. 0. Emery and G. C. Spencer, J . Id. Eng. Chem., 1918, 10, 605;A., ii, 380.?D T. F. Harvey and C. F. Sparks, J . SOC. Chem. Ind., 1918, 37, 4 1 ~ .*O S. L. Jodidi, J . Amer. Chem. SOC., 1918, 40, 1031 ; A., ii, 379.81-Compare E. M. Chamot and H. I. Cole, J . Ind. Brig. Chem., 1917, 9,83 E. M. Chamot rcnd H. I. Cole, ihid., 1918, 10, 48; A., ii, 129.969 ; A,, 1917, ii, 676ANALYTICAL CHEMISTRY. 131detection of the iodide in the filtrate by oxidation with potassiumpermanganate in the presence of sulphuric acid and chloroform.Comparative experiments with different oxidising agents haveshown that the liberation of iodine from potassium iodide is leastaffected by cyanides when permanganate is used as the oxidisingagent.83A solution of mercuric nitrate in nitric acid may be used forthe detection of the sulphuric ion in insoluble sulphates.Thisreagent forms turpeth mineral, which may readily be identifiedunder the microscope. In the case of mixtures, the Pulphateshould be precipitated as barium sulphate. and the test appliedto the precipitate.84A method of detecting selenium in sulphuric acid depends onthe fact that such acid shows a pronounced violet coloration whentested with aspidospermine. Sulphuric acid free from seleniumdoes not show this reaction, but after the addition of an oxidisingagent produces a rose-red coloration.86The detection of phosphoric acid by means of molybdic acidsolution is rendered ten times more sensitive by the addition ofpyridine to the reagent.86The compounds formed on adding a concentrated solution ofpotassium iodide to ammoniacal solutions of cadmium and nickelsalts afford a means of separating and identifying those metals inpresence of other metals.Cadmium forms an insoluble, white pre-cipitate, Cd(NH3)%12, composed of white octahedra, whereas coppergives no precipitate with the reagent. The nickel compound isbluish-violet, has the formula Ni(NH3)&, and is also composed ofregular octahedra. Cobalt forms an analogous precipitate, andshould therefore be separated before applying the test for nickel.87On heating for a few minutes a solution containing osmium inthe tetroxide condition, or an osmichloride, with an excess of thioccarbamide and a few drops of hydrochloric acid, a coloration isobtained ranging from rose to deep red, according to the concen-tration of the osmium. The reaction, which is capable of detect-ing 1 part of osmium in 100,000, is due to the formation of a redcompound of the composition [Os6NH2*CS*NH2]Cl,,H,0.*~Other colour reactions which have been described are those givenby thorium and zirconium with an aqueous solution of pyrogallol-L.J. Curtman and C. Kaufmas, J. Arner. Chem. Soc., 1918, Po, 914;A., ii, 272.s4 G.DenigBs, Bull. SOC. chim., 1918, [iv], 23, 36 ; A., ii, 82.R5 L. P. 5. Pslet, Anal. SOC. Quirn. Argentina, 1917, 5, 121 ; A., ii, 127.86 G. Vortmsnn, Zeitsch. anal. Chern., 1917,56, 465 ; A., ii, 129.B s L. A. Tschugaev, C m p t . rend., 1918, 167, 235 ; A., ii, 335.A. Agrestini, Oazzettu, 1918, 48, ii, 30 ; A., ii, 455.I?:132 -4NNUA1, REPOWS ON THE PRUQBESS OF CHEMISTKP.aldehyde. This reagent gives a yellow coloration and preoipitatewith thorium salts, whilst with zirconiuin compounds it producesa similar coloration and precipitate after boiling or the addition ofhydrogen peroxide. The test is capable of detecting 0.1 milligramof thorium nitrate in 100 C.C. The reaction is not produced bypyrogallol, pyrogallolcarboxylic acid, or protocat~echualdehyde.89&uautitative.-The use of thymolsulphophthalein as an indicatorin acidimetric titrations has many advantages, owing t o the factthat it shows two distinct changes of colour at different hydrionconcentrations.It may therefore be used for the differential titra-tion of mixtures of weak and strong acids, such as benzoic andhydrochloric acids, or acetic and sulphuric acids, although in thelatter case the error may be as much as +O-5 per cent. Anotherapplication of this indimtor is in the titration of aniline withhydrochloric acid.90I n t,itrating free hydrochloric acid in gastric juice, usingdimethylaminoazobenzene, Conga-red, or tropzolin as indicator, thepresence of large amounts of organic acids, or of hydrochloric acidin a state of loose combination, renders the result8 uncertain.This may be obviated by adding alcohol to prevent the dissocia-tion of organic acids, and thus suppress their acid propertiestowards the indicators.QlThe alkalinity of very dilute solutions (AT/ 10,000 to ,V/40,000)may be estimated by means of an iodotannic reagent consisting ofa mixture of N/lO-iodine solution and 1 per cent.t'annin solut.ion.The alkaline solution is run into 2 C.C. of the reagent. until a dis-tinct red colour appears, after which it is gradually introduced,and a drop of the mixture tested with starch-paper after eachaddition until a blue colour is no longer produced.92A method of estimating the alkalinity of certain liquids, suchas soap solutions, has been based on the measurement of the volumeof nitrogen which the solution liberates from a nitrosoarnine. Thisgives results sufficiently trustworthy for practical Purposes,although not so accurate as those obtained by measuring thepressure of the gas.Nitrosotriacetonamine and nitrosovinyldi-acetonamine are suitable compounds for tdxations within definitelimits of hydroxyl-ion concentration.g3An acidimetrio method of t*itrating zinc will be found of use89 H. Kaserer, Chem. Zeit., 1918, 42, 170 ; A., ii, 244.90 A. B. Clark and H. A Lubs, J . Amer. Chem. SOC., 1918, 40, 1443 ; A,9 1 G. Kelling, Bedin. Klin. Woch., 1918, 54, 334; A., ii, 450.92 D. E. Tsrtkalotos and D. Dalmas, BuW. Soc. chim., 1918, [iv], 23, 391 ;9s F. Prancis, J . SOC. Chem.Ind., 1918, 37, 2521..ii, 449.A., ii, 4.54ANALYTICAL CHEMISTRY. 188when a rapid estimation of the metal is required. The solution,which must contain the zinc in the form of chloride and be freefrom other heavy metals, is neutralised with sodium hydroxide,methyl-orange being used as indicator, and, after the addition ofphenolphthalein, is titrated with N / 10-sodium hydroxide solution.The end-point of the titration is indicated by the pink colour notdisappearing when the liquid is boiled. The precipitated zinchydroxide does not interfere with the accuracy of the results.94Several new iodometric methods have been published during theyear. For the estimation of copper and iron, advantage has beentaken of the fact that the salts of both metals liberate iodine froma solution of potassium iodide in dilute acetic acid.When bothiron and copper- are present, the former may be precipitated asferric phosphate, which does not3 liberate iodine from potassiumiodide, and the liquid again titrated. The iodine found in thefirst titration is equivalent to the copper and iron together, whilstt.hat obtained in the second titration corresponds with the amountof copper. The method is also applicable in the presence of zincand al~minium.9~In another iodometric method of estimating copper, the solutionof the metal is nearly neutralised, and the copper converted intocupric acetate. After the addition of excess of sodium thio-sulphate and slight excess of potassium thiocyanate, the liquid isfiltered from the cuprous thiocyanate, and the excess of thio-sulphate in the filtrate titrated with standard iodine solution. Ofthe common metals, only iron interferes with the estimation.96I n estimating sulphites by oxidation to sulphates by means ofpotassium iodate, it is essential that there should be an excess ofthe iodate and sufficient hydrochloric acid to prevent the hydrolysisof the iodine chloride formed in the reactionHZS + 2KIO3 + 4HC1= 2ICl+ H,SO, + 2H2O + 2KC1.The excess of iodate is t.hen estimated by means of standard iodinesolution.The method may also be used for estimating leadsulphide, which is introduced in a freshly precipitated state intokhe i d a t e soluticm.97In estimating selenious acid by the direct process, it is necessaryto add four times the theoretical amount of potassium iodide, toheat the mixture with hydrochloric acid in a distillation flask, andto titrate the iodine both in the receiver and the residue.The94 R. Howden, Chem. News, 1918, 117, 322 ; A., ii, 408.9t3 J. Moir, Chem. News, 1918, 117, 133 ; A., ii, 83.9 7 R. S. Dean, J. Amer. Chem. Soc., 1918,40, 619; A., ii, 204.H. Ley, Chem. Zeit., 1917, 41, 763 ; A., ii, 21134 ANNUAL REPOItTS ON THE PROGRESS OF CHEMISTRY.indirect method08 is also trustworthy when a similar procedure isused. Selenic acid is best estimated by reduction with hydriodicacid .Q9In analysing a mixture of phosphorous, hypophosphorous, andphosphoric acids, the phosphorous acid may first be estimated bydetermining the iodine absorption of the solution.The hypo-phosphorous acid is then hydrolysed in the presence of hydrochloricacid in accordance with the equation H,P,OG + H,O = H3P0, +?&PO,, and the resulting phosphorous acid estimated iodometricallyas before. Finally, the solution is oxidised and the total phos-phoric acid estimated.'For the estimation of hypobromite in the presence of bromateor hypoiodite in the presence of iodate, the hypobromite or hypo-iodite is oxidised by means of a mixture of sodium hydroxide andhydrogen peroxide, XaBrO + N,02 = NaBr + H20 + O f , the liquidboiled to expel the excess of hydrogen peroxide, potassium iodideand sulphuric acid are added, and the iodine liberated by thebromate is titrated. Another portion of the solution is treatedwith potassium iodide and sulphuric acid t o obtain the iodineequivalent of the hypobromite and bromate together, and thehypobroinite is obtained by difference.2 A method of estimatingiodates and broniates in the same solution has been based on thefact that bromates are gradually decomposed by dilute hydro-chloric acid, with the formation of hydrobroinic acid and hypo-chlorous acid, whilst iodates are not affected.The iodine equi-valent of the two compounds together is obtained as describedabove. Another portion of the solution is then treated with dilutehydrochloric acid, and subsequently oxidised with hydrogen per-oxide and sodium hydroxide, and the iodine equivalent again deter-mined. The difference between the amounts obtained in the twotitrations corresponds with the bromate.3An iodometric method of estimating nitrites has been based onthe reaction NaNOo + 2HI = NaI + I + NO + H20, which is carriedout in a series of connected flasks. The liberated iodine is titratedwith arsenious acid.4I n this connexion, mention may also be made of a general methodof estimating iodine in inorganic and organic compounds, based on98 F.A. Gooch and A. W. Peirce, Zeitsch. nizorg. Chem., 1896, 11, 249 ;g9 L. Moser and W. Prinz, Zeitsch. anal. Chem., 1918, 57, 277 ; A., ii, 451.1 R. G. van Name and W. J. Huff, Amer. J . Sci., 1918, [iv], 6, 91 ; A.,a E. Rupp, Zeitsch. anaL Chem., 1918, 57. 16 ; A., ii, 125.4 F. Dienert, Compt. T e d . , 1928, 167, 366 ;I A.,iii, 370.d., 1896, ii, 334.ii, 128.E.Rupp, ibid., 19 : A., ii, 126ANALYTICAL CHEMISTRY. 135its conversion into iodine trichloride. The iodine liberated in thereaction, GFeSO, + 3H,S04 + 21C13 = 3Fq(S04), + 21 + 6HC1, is ex-tracted with chloroform and titrated with thiosulphate solution.6An oxidimetric method of estimating thorium has been described.The thorium is precipitated as oxalate, and the precipitate heateda t 8 5 O with dilute sulphuric acid, and titrated first in the cold andfinally at. 8 5 O with standard potassium permanganate solution. Ifa known excess of oxalic acid has been used for the precipitation,the filtrate may be heated to 8 5 O and titrated with permanganate.6An extension of the method may also be used for estimatingfluorine.The fluoride is precipitated as thorium fluoride by meansof an excess of thorium, the excess of which, in turn, is precipitatedas thorium oxalate.'Metallic silver may be used as a reducing agent in the volu-metric estimation of iron, the dissolved silver being subsequentlyprecipitated as thiocyanate. The filtrate is treated with an excessof silver nitrate and titrated with potassium permanganate solu-tion. The presence of titanium does not affcct the results, butvanadium is quantitatively reduced by silver.* Titanous chloridemay also be used as a reducing agent for ferric salts, the excessbeing subsequently removed by means of copper sulphate .QIt has been pointed out that in titrating potassium permanganatesolution containing nitric acid with sodium arsenite, the latter hasa reducing value considerably in excess of that shown when noacid is present.It is probable that a manganic compound isformed under these conditions.**In estimating vanadium and molybdenum volumetrically bymeans of titanous chloride,ll the addition of the indicator,potassium thiocyanate, before the titanous chloride causes thevanadic acid to be reduced first. Advantage may be taken of thisfact in the analysis of steel, the vanadium and molybdenum beingfirst estimated together as described (Zoc. c i t . ) , and the vanadiumthen separately titrated after the addition of thiocyanate.12To obtain trustworthy results in the titration of chlorides byVolhard's method, the liquid should be stirred a t the first indica-6 N.Tarugi, ffuxzetta, 1918, 48, ii, 1 ; A., ii, 203.0 F. A. Gooch and M. Kobayashi, Amer. J . Sci., 1918, [iv], 45, 227 ; A,7 Ibid., 370 ; A., ii, 239.ii, 177.G. Edgar and A. R. Kemp, J . Amer. Chem. Soc., 1918, 4Q, 777 ; A.,L. Brandt, Chem. Zeit., 1918, 42, 433, 450 ; A., ii, 409.lo F. Ibbotson, Chem. News, 1918, 117, 167 ; A., ii, 175.A. Travers, Compt. rend., 1917,165,362 ; A., 1917, ii, 645 ; Am,. Report,A. Travers, i b i d , 1018, 186, 289: A., ii, 136.ii, 242.1917, 165136 ANNUAL, H.EPOR'J.S ON THE PROGRESS OF CHEMISTRY.tion of change of colour, and the titration then completed. Thio-cyanates, if present, should be oxidised with sodium peroxide insulphuric acid solution before the titration.13 In using the methodconversely for the estimation of silver, the presence of other metals,such as mercury, lead, nickel, or cobalt., or of lower oxides ofnitrogen, causes the results to be inaccurate.The use of palladiousiodide as indicator renders the method more trustworthy andsensitive and capable of being used in the presence of the sub-stances mentioned. The addition of a small amount of gum arabicis advisable t o prevent the precipitation of silver or palladiousiodide during the titration.14A volumetric method of estimating chlorides. bromides, andcyanogen consists in titrating the solution with standard mercuricnitrate solution, using sodium nitroprusside as indicator. Theresults are more accurate than those obtained by Volhard's method,and the method can be used in the presence of sulphates and phm-phates, although sulphites and nitrites must be removed before thetitration.Conversely, the method is applicable to the estimationof mercury.15The presence of dissolved or gelatinous silica does not interferewith the titration of chlorine with silver nitrate, provided thatthe liquid is made neutral to phenolphthalein with nitric acid, andany resulting gelatinous mass is finely distributed throughout theliquid before introducing the reagent.16One objection to the method of titratiug copper with potassiumcyanide solution is that the end-point of the reaction is no longersharp when much less than 1 gram of copper per litre is present.For smaller quantities, a volumetric method has been based on thefact that a solution of a double carbonate of copper and an alkalimetal in excess of sodium carbonate solution gives a sharp reactionwith potassium cyanide.The double carbonate is prepared byadding a solution of sodium carbonate and sodium hydrogencarbonate t o the copper s01ution.l~The results obtained by the volumetric method of estimatinglead by means of ammonium molybdate, as ordinarily used, are toohigh. To obviate this, it is essential to dissolve the lead sulphatein the smallest possible quantity of ammonium acetate solution.18Calcium may be estimated volumetrically by precipitating itunder specified conditions with an excess of ammonium oxalate,18 I. M. Kolthoff, Zeihh. anal. Chem., 1917,58, 568 ; A., ii, 124.14 L. Schneider, J .Amer. Chem. Soc., 1918, 4Q, 583 ; A., ii, 205.16 E. Votolek, Chem. Zeit., 1918, 42, 267 ; A., ii, 238.18 G. Bruhns, Zeitsch. angew. Chem., 1918, 31, i, 156 ; A,, ii, 368.1' M. P. Applebey and K. W. Lane, ArtaZy&, 1918,43, 268 ; A., ii, 276.I f i L h d t . Zeifsch. anal. Chem., 1918, 57, 71 ; A., ii, 242AN A LYTlCAL C! H EMISTRY. 137the excess of whicli is subsequently Iitrated in the tiltmte IJY meansof potassium permanganute solut-ion.19Turning to the gravimetric methods, it will be found that severalnew methods of separating metals in different groups have beendescribed. For example, for the separation of copper, zinc,cadmium, nickel, and 'cobalt, the metals are precipitated by rneaiisof sodium carbonate, the precipitate is dissolved in the minimuniquantity of ammonia solutioii, and t.he liquid dilated and boileduntil reprecipitation is complete.The precipitate may be an oxide,as in the case of copper, a hydroxide or hydrocarbonate, as in thecase of zinc and nickel, or a carbonate, as cadmium carbonate.The precipitate is ignited, or sometimes is preferably reduced withhydrogen, and the metal weighed. For t.he separation ofindividual metals, -modifications of varions well-known methods maybe employed.29Another new method is coiicerned witlh the separat.ion of metalsof the copper group from t.hose of the arsenic group. It is basedon the facts that the sulphides of mercury, arsenic, antimony, andtin are soluble in n solution of sodium hydroxide saturated withhydrogen sulphide, ancl then mixed with n more concentratedsodium hydroxide solution, whereas the sulphides of lead, bismuth,copper, and cadmium are insoluble therein .zlDicyanodiamide sulphate is a convenient reagent to use f o r thequantitative precipitation of copper or nickel when it3 is desirablenot to use an alkali hydroxide.It may also be used as a groupreagent for separating copper and nickel from zinc, aluminium,arsenic, lead, and antimony.22The use of hydrofluoric acid in eleetxochemical analysis is men-tioned elsewhere.23 A further application of this reagent has bee11based on the fact that stannic tin and tungsten are not precipi-tated by hydrogen sulphide from an acidified fluoride solution, anclmay thus be separated from copper, lead, silver, mercury, auti-mony, and arsenic .z*The accuracy of the results obtained by estimat.ing sulphuric acidas barium sulphate depends to a considerable extent on the rate a twhich the barium cbloride is added, whilst other factors, such asthe concentration, the amount of stirring, and the acidity of theliquid have a much smaller influence.At least one and a-halfl9 J. Grossfeld, Chern. Zeit., 1917, 41, 842 ; A., ii, 83.2o A. Carnot, Compt. rend., 1918, 166, 245, 329 ; A., ii, 133.21M. C. Sneed, J . Amer. Chem. SOC., 1918, Lu), 187; A., ii, 133.22 H. Grossmann and J. Mannheim, Chem. Zpit., 1915, 42, 17 : A . , ii, 175.24 N. H. Furman, J . Amev. Chem. SOC., 1918, 40, 895; A . , ii, 277.See p. 140.F138 ANNUAL REPORTS ON THE PROGRESS OF CHEMLSTRY.minutes should be allowed for the addition of the reagent. In thepresence of potassium salts, the results are too low, but tend tocompensate the high results caused by a too rapid addition ofbarium chloride.26Gravimetric methods of estimating chromates and dichromatesas barium chromate and as silver chromate have been described.In each case, the insoluble chromates are precipitated and washedunder specified conditions, dried a t 1 3 2 O , and weighed.The silvermethod is the more trustworthy, but is not applicable in thepresence of chlorides, whilst the barium method cannot be usedin the presence of sulphates. Nitrates, chlorates, and acetates donot affect the results, but even when the silver method is used,sulphates cause the results to be too high.26A similar method has been devised for the estimation ofstrontium, which is precipitated as sulphate, carbonate, or oxalate,preferably the last.In each case, the precipitate is washed witha saturated solution of the respective strontium salt, dried a t1 3 2 O , and weighed. It should be noted that magnesium chlorideinterferes with the estimation as oxalate.27 For the separation andestimation of barium when associated with strontium, the saturatedsolution of the two chlorides is treated with a mixture of hydro-chloric acid and ether, and the precipitated barium chloride washedwith the same mixture, dried at 150°, and weighed.28For the estimation of magnesium, the compoundMgNH,PO,,GH,Ois precipitated a t 90°, washed with ammonia and methyl alcohol,dried over calcium chloride, and weighed.The method cannot beused, however, when any considerable quantity of potassiumchloride or sodium chloride is present.29Several new methods of separation by means of volatilisationhave been published. When tantalum is precipitated as tantalicacid, the silica which is usually present cannot be separated bytreatment with hydrofluoric acid without some loss of tantalum.To obviate this difficulty, the tantalic acid may be volatilised in acurrent of hydrogen chloride a t 900°, and the residual silicaweighed .SOOther volatilisation methods have been devised for vanadium,2. Raraoglanow, Zeitmh. anal. Chem., 1917, 58, 417 ; 191 8, 57, 77 ;A., ii, 47, 239. Zeitsch.angew. Chem., 1918, 31, i, 160; A., ii, 369.9e L. W . Winkler, Zeitach. angew. Chm., 1918, 31, i, 46; A., ii, 176.IGd., 80, 83 : A., ii, 241.F. A. Gooch and M. A. Sodeman, Amer. J . Sci., 1918, [iv], 48, 638;L. W. Winkler, Zeitsch. angew. Ohem., 1918,31, i, 211 ; A., ii, 466.A. Travers, Compt. rend., 1018, 166, 491 ; A , , ii, 177.A., ii, 408ANALYTlCAL CHEM LSTRY. I 3 9molybdenum, and tungstic acid. In the case of vanadium, thecompound is heated in a current of carbon dioxide and carbontetrachloride in a silica tube, and the resulting vanadium chloridescollected in dilute nitric acid and water. The vanadic acid is thenreduced to vanadyl sulphate, and the solution titrated withstandard permanganate solution .31 Xolybdenum compounds arevolatilised a t 400-560c in carbon tetrachloride vapour, and thevolatilised molybdic acid is collected, evaporated with nitric acid,and weighed.32 For the volatilisation of tungstic acid, a current ofcarbon dioxide saturated with carbon tetrachloride vapour is used,and the separated acid treated as in the case of rnolybdic acid.33The new colorimetric methods include one for the estimation ofmanganese, which depends on the oxidation of manganese salts bymeans of an alkali periodate in acid solution, and comparison ofthe resulting permanganate with standard solutions.34 Tungsticacid may also be estimated colorimetrically by reducing it by meansof titanous chloride, and comparing the blue oxide which remainsin suspension under certain conditions with standard suspensionsof known composition.The method is not applicable in thepresence of vanadium, phosphorus, or molybdenum, and these ifpresent must be removed prior t o the estimation.3581 ectro chemical A nalysisFurther applications of the electrometrjc method of titration 36have been described during the year. For example, it is a con-venient method of estimating manganese in steel. For this pur-pose, the manganese is oxidised to permanganate by means ofsodium bismuthate or ammonium persulphate and the resultingsolution titrated with mercurous nitrate solution. The presence ofchromates or vanadates does not interfere with the estimation.37Another modification ot the method has been devised for the titra-tion of solutions containing proteins, a special apparatus being usedto prevent local reactions when the reagent first, comes in contactwith the solution.3831 P.Jannasch and H. E. Harwood, J . p r . Chenz., 1918, [ii], 97, 93; A.,s8 P. Jannasch and R. Leiste, ibid., 141 ; A., ii, 460.84 H. H. Willard and L. H. Greathouse, J. Amer. Chern. Soc.? 1917, 39,36 A. Travers, Compt. rend., 1918, 166, 416 ; A., ii, 176.36 Compare Ann. Report, 1917, 166.87 G. L. Kelley, M. G. Spencer, C. B. Illingworth, and T. Gray, J . Ind.Eng. Chem., 1918, 10, 19; A., ii, 134.3* J. C. Baker and L. L. Van Slyke, J . Biol. Chem., 1918, 35, 137; A., ii,380.ii, 373. 32 P. Jannasch and 0. Laubi, ibid., 153 ; A., ii, 489.2366 ; A., ii, 84.b1”* 140 ANNUAL REPOETS OX THE PH-OGRESS OF CHEMIS'YRI:On titrating oxalic acid with sodium hydroxide solution, a sharpchange occurs in the electrical conductivity of the liquid a t themoment when the first hydrogen atom is displaced by sodium.Should, however, the sodium hydroxide contain carbonates, theresults obtained in the estimation of oxalic acid will be too high.By means of this method, it is also possible t.0 titrate strong acidsin the presence of weaker acids.3QAn apparatus has also been devised for measuring the densityand the amount of salts in a liquid by means of its electrical con-ductivity a t a definite temperature.The current is derived fromtwo electrolytic cells connected wit?h an alternating current galvano-meter and a recorder. A method of this sort should prove usefulfor following the progress of concent?ration of liquids beingevaporated.A method of estimating vanadic acid has been based on its reduc-tion in the presence of sulphuric acid by means of anodes of silveror copper in rapid rotation in an electrolytic cell, or by means ofa rotating cylinder of zinc.Over-reduction is prevented by theaddition of silver sulphate, and the completion of the reduction isshown by the appearance of metallic silver. The liquid is thenfiltered and the vanadium estimated by titration with potassiumpermanganate. The best results are obtained by the use of silverplated with pure copper.41It has been found that hydrofluoric acid is a useful reagent forelectrolytic separations. For example, copper can be quantita-tively separated from vanadium, tin, or tungsten and electrolytic-ally deposited from an acid fluoride solution.Uranium andtitanium behave in the same way as vanadium. The stannic iondoes not appear to be present to any notable extent in acid fluoridesolutions of stannic tin, but on adding boric acid to the solution,tjhe tin may then be separated either electrolytically or by meansof hydrogen sulphide.42By fractional electrolysis of a dilute solution of the sulphates ofgallium and iridium, it is possible to separate the gallium in apure condition, but it. is necessary to repeat the electrolysis aboutfourteen times .4539 H. S. Harned and C. N. Laird, J . Amer. Chem. SOC., 1918, 40, 1213 ;40 E. E. Weibel and A. L. Thuras, J . Id. Eng. Chem., 1918, 10, 626 ; A.,4 1 I?.A. Gooch arid W. Scott, Amer. J . Sci., 1918, [iv], 46, 427 ; A., ii, 373.42 N. H. Furman, J . Amer. Chem. SOC., 1918, 40, 895; A., ii, 277.43 L. M. Dennis and J. A. Bridgman, ibid., 1531 ; A., ii, 456.A,, ii, 412.ii, 368ANALYTICAT, CHEMISTRY. 141Water Analysis.The introduction of rapid methods of examining water for theuse of armies in the field has been one of the features of recentwork in this branch of analysis.44 For the rapid deterniination ofthe hardness of water on the spot, Blacher's method of titrationwith potassium palmitate is in general the most suitable, and thereagent is prepared for the purpose in the form of standardisedpellets.45It has been found that Wartha and Pfeiffer's method46 ofestimating the hardness is rendered more trustworthy, especially inthe case of waters rich in magnesium salts, by increasing theamount of sodium carbonate to 14.5 grams, and that of the sodiumhydroxide to 8.01 grams, per litre.47A suggestion has been made that the hardness of water might beestimated by measuring the increase in the surface tension afterthe addition of calcium or magnesium salts to an alkaline soapsolution.48For the rapid estimation of magnesium in water, an alkali-metric method has been devised.The water is rendered neutralto methyl-orange and treated with potassium oxalate in slight.excess of the amount. equivalent to the calcium present, and thenwith a measured excess of a mixture of standard alkali hydroxideand carbonate solutions. The liquid is then made up to definitevolume and filtered, an aliquot part of the filtrate treated with anamount of calcium chloride equivalent to the excess of potassiumoxalate used, and the excess of alkali titrated.49I n the colorimetric estimation of lead in water. the salts presenthave a considerable influence on the intensity of the colour reac-tion. To obviate this, it is necessary to prepare the standard leadsolutions for the comparison from the same water which has pre-viously been freed from lead. Comparisons made with standardsprepared from distilled water may give results much too l0w.50A colorimetric method of estimating minute quantities ofvanadium in water has been based on the fact that diphenylaminegives a violet coloratioii with aq ueom solntions of vanadium com-I4 See Ann. Report, 1916, 192.Is A. S. Behrman, Ph'ilippinc J . SC.~., 1918, 13 [A], 21 ; A., ii, 206.'13 J. Zink and F. Hollandt, Zeilach. angew. Chem., 1914, 27, 235; A., 1914,ii, 490.Wagner, Zeitsch. 6ffentl. Chem., 1917, 23, 375 ; A., ii, 174.L. Berczeller, Biochern. Zeilach., 1917, 84, 149: A., ii, 132. ComparePhysical Methods.4g M. Monhaupt, Chem. Zeit., 1918, 42, 338: A,, ii, 336.6 o R . Maldrum, Chem. News, 1915, 47, 49 ; A , , i i , $3142 ANNUAL REPORTS ON THE PROGRESS OF CHEMTSTRY.pounds acidified with hydrochloric acid. The test is capable ofdetecting 0.002 per cent. of vanadium, and is not affected by smallquantities of iron, titanates, or nitrates, but in the presence of freenitric acid the method would require modification. For a quanti-tative estimation, the colour may be compared with that given bysoluti&x containing known quantities of ammonium vanadate.51I n Riegler’s colorimetric method of estimating phosphoric acidin water, the hydrazine sulphate may conveniently be replaced bystannous chloride.52A new colorimetric method has also been devised for the detec-tion of nitrites in water. The sample is treated first with anti-pyrine solution, then with mercuric sulphate solution, and finallywith a few drops of potassium ferricyanide solution, a red color-ation being produced in the presence o€ a trace of nitrite. Thetest is also applicable to nitrates after reduction to nitrites.62C. AINSWORTH MITCHELL.61 V. L. Meeurio, Anal. SOC. QuCm. Arqentina, 1917, 5, 185 ; A., ii, 135..*PP. N. van Eck, Pharrn. Weekblad, 1928, 55, 1037; A., ii, 370.Esceich, J. Phnrm. Chim., 1918, rvii], 17, 395: A , , ii, 273

ISSN:0365-6217    

DOI:10.1039/AR9181500118

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

PHYSIOLOGICAL CHEMISTRY.SIR HENRY THOMPSON, late Professor of Physiology at TrinityCollege, Dublin, whose death was due to the dastardly outragewhich sank the Leinster, was the only individual who before thewar pad taken the trouble to estimate a nation's actual food sup-ply-imported and home produced-in terms of protein andcalories. The items as found in the returns of, say, the Boardsof Trade and Agriculture-so many tons of this and so many tonsof that-tell little on mere inspection with regard to the nutritivevalue of the supply, Thompson, however, had made the necessarycalculations in the case of Ireland some time before the war. Theinterest he took in such matters led to' his becoming a member ofthe Royal Society Food (War) Committee, He went as a repre-sentative of that Committee to the Ministry of Food, and after-wards became scientific adviser to the Ministry.The honour ofknighthood which was the reward of his official services wasenjoyed for a period most sadly brief. Thompson was anenthusiastic student of the science of nutrition, and. although notrained chemist, he had other high qualifications as a worker a tthe subject. His teaching and influence will be greatly missed.The Fapers dealing with the dynamic side of physiological chem-istry-the processes of metabolism-to which I have hitherto givenchief attention in these Reports have been few and, for the mostpart, unimportant this year. I shall therefore give more atten-tion than usiial to other aspects of the subject.Emulsoid Colloids : Carbon Dioxide in Btood.It is justifiable to recall sometimes that in this country occurred,not only the birth of colloid chemistry, but its awakening topresent activity.Graham presided a t its birth and endowed i twith much material for growth; but the infant science promptlywent to sleep for more than thirty years. Linder and Picton in1892 began to make important provision for its future, but it%14144 AKNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.actual awakening to what. has siuce become so robust an existencewas due to W. B. Hardy, whose studies -were stimulated by theneeds of biology. I think that anyone who reviews the literaturebefore and after 1899, when Hardy’s first papers were published,will be convinced of the essential rightness of this claim.After-wards came ‘* German industry ” and-the deluge.After two decades, however, of intensive study of the colloidstate, we have hitherto lacked really illuminating knowledge ofemulsoid as distinct from suspeiisoid systems. Generalisat.ionsfrom studies of the latter have domiiiated theory. Yet, theoretic-ally and in practice, emulsoid dispersion is a t least of equal import-ance with suspensoid dispersion. I n physiological chemistry it isof parthicular interest., because the mise e n .sc&c for the drama ofmetabolism is largely built of ernulsoids.An enlightened study of an emulsoid colloid by S. P. L. Soremenand various co-workers, of which the results appear in a monographrecently published, will be greatly welcomed by all who have feltthe lack of accizrate information concerning the properties ofproteins in ‘.native *’ solution. The monr\graph can now beobt.ained in an English translation, wliiclz for 3ome reason is calledoil its title-page ‘‘ Edition Frangaise.” * It may be noted that awhole number of t h e Zeitsclirift fiir physiologische Chemie isdevoted to a reproduction of the work.?Soremen has attacked the subjecth by means of an intensive studyof a single substance, regarding it simultaneously from a chemicaland a physico-chemical point of view. The material used wascrystalline ovalbumin prepared by the method described by F. G.Aopkins a i d S. N. Pinkus. It was shown long ago that, so faras constancy of optical relation after successive recrystallisationscould be a guarantee of purity, the albumin obtained by thismethod is a pure product.3 Sorsenseii found it.to representmaterial so well defined as to allow of an exact reproduction ofconditions in each experiment. of a series. The work described inthe monograph was done on rigidly quantitative lines. Much ofthe technique was original. The results are fully discussed andthe conclusions are drawn with much insight.Perhaps khe most fiindsniental part of the work is the proofthat the essential phenomena exhibited by emulsoid solutions canbe interpreted by the laws which hold for true solutions. Thei~iaking of sharp distinctions between colloid and crystalloid solu-tion is not justified ; the emulsoid is a bridge between the silspensoidI Compteu rend.Tmu. Lab. Carlsberg, 1907, 12.Zeitsch. physiol. Chent., 1918, 103, 1.F. G. Hoplrins, J. Physiol., 1900. 25, 206 ; A . , 1900, i, 466PH YSIOLOGJCAL CHEMLSTRY. 145and hhe crystalloid. I n a chapter dealing with the conditions ofequilibrium between the crystals of albumin and the constituentsof their mother liquor, it is shown that Gihbs’s phase rule is per-fectly applicable t o the system. The osmotic pressure of solutionsof the albumin was submitted to ail elaborate investigation.Donnan’s formula is successfully elaborated to suit the particularconditions present, and it is finally shown that the osmotic pressureof a correctly defined einulsoid solut.ion is as real and as constanta quantity as that of ally crystalloid solution of definite composi-tion.Such conclusions as these, and there are others of almostequal importance, are arrived a t after a very careful st’udy of anumber of individual variables. The monograph is long, extend-ing t o 370 pages. It is impossible, therefore, to give even anepitome of the experimental details contained in it, but I may addthat, apart from the results. the technique described will affordreal help to other workers.The impedance oE the purely physical properties of the blood-proteins as einulsoid colloids in maintfaining the normal relationsof the circulation Elas been rather overlooked of late. This isowing perhaps to the success with which many isolated organs cancarry out their functions when perfused with non-colloidal solu-tions, such as oxygenated Ringer’s or Locke’s solution.The needsof medical and surgical pactlice during the war have once moreemphasised the importance of the colloids. When simple salinesolutions are used in attempts to restore the blood pressure afterit has been lowered by h a o r r h a g e o r shock, no1 more than at.emporary rise is obtained, and the condition may quickly becomeworse than before treatment. The intravenous injection of asolution containing 6 per cent. of gum acacia and 0.9 per cent. ofsodium chloride will, on tbhe other hand, permanently restore thenormal blood pressure .4 Gelatin solutions of the same concentra-tion are also effective, although they are more liable to show sometoxicity.5 The osmotic pressure of the colloids, and perhaps theirviscosity, must, be supposed to play the chief part in producing thisnotable effect, and the proteins of normal blood owe much of theirimportance in the circulating fluid to their colloidal attributes.It would be a grave mistake, however, t o take a view of theirfunctioiis which is too purely physical. The one function we haveto deny to the blood proteins is that of representing nutritiveW.M. Bayliss, Med. Res. Committee Reports of the Special Investigationon, Surgica2 Shock a d Allied Conditions, No. 1, November, 1917.H. Drumrnond and E. S. Taylor, ibid., No. 3, 1918; W. M. Bayliss,Proc. Roy. SOC., 1916, [B], 89: W. 91. Baylisa, Proc. ph,ysioZ. SOC., J.P h p i o t . , 1918, 52, svz1146 ANNUAL REPORTS OW THE PROGRESS OF CHEMISTKI.’.material in course of transport from gut to tissue.6 In thechemical equilibrium of the blood itself they undoubtedly play animportant part., although the extent of i t is just now the subjectof fresh discussion.Sorensen7 insists that a t the bottom of thedifferences between suspensoid colloids and emulsoid colloids liesthe fact that the latter, unlike the former, when forming the dis-persed or internal phase of a system, react chemically on theexternal phase. The chemical nature of the particles has relativelysmall influence in determining the properties of suspensoid solu-tions. In emulsoid solution, the chemical properties of the dis-solved material are of much greater importance. Ostwald’s dictumthat colloid chemistry is “the science, not of colloid materials, butof the colloidal condition,” is untrue when emulsoids are concerned.I n last year’s Report I dealt a t considerable lenqth with theneutralising power of blood-with its so-called alkali-reserve.”I pointed out that the buffer action of the blood has, since thetheoretical and experimental studies of L.J. Henderson, beenattributed almost entirely to the inorganic salts present; jn thecase of the plasma, almost exclusively to the sodium bicarbonate.The claim that the proteins, as amphoteric substances, play animportant part in maintaining the hydrion concentration has,however, been again raised ,* and again sharply criticised.9 It issure that the ‘‘ reactivity” of pure proteins is too small to con-tribute more than a small proportion of the buffer effect observedwhen, by the addition of acid or alkali to blood, the hydrion con-centration is made to change within the very narrow limit9 whichare phvsiological.I am not quite sure, however, that all suchfactors of eqiiilihrium in the blood are vet understood.Siirensen devotes an important section of his monograph to arnqthevatical discussion of the capacity of ampholytes in general,and of albumins in particular, to combine with acids or bases, bothi n salt-free solutions and also, an important addition, in solutionscontaining neutral salts. I feel unable to make this discussionintelligible here, but it should be read by those who are workingat the subject.I f the buffer mechanism of the blood still offers difficulties, soalso, and to a greater extent, does the closely related subject ofcarbon dioxide transport by the blood.That the bicarbonate of the plasma plays, a t any rate, a veryimportant part in stabilising the reaction of the blood is sure.* For evidence of this on somewhat new lines, see 8.Hanson and I. McQuarria,7 LOC. C i t .J . Pharrn. Expt. Ther., 1917, 10, 261.8 B. Moore, &it. Med. J., 1918, i, 920,W. M. Bayliss, ibid., 1918, ii, 78PHYSIOLOOICAL CHEMISTRY. 147Does it also represent the combination in which carbon dioxide iscarried from the tissues to the lungs ? It has been recently shown lothat bicarbonate does not dissociate a t all when exposed to thecarbon dioxide tension of the alveolar air.A t the temperature ofthe body, sodium bicarbonate does not dissociate until the carbondioxide tension is reduced to 2.25 mm. of mercury, whereas thetension in the lungs is of the order of 40 mm., a t which a solutionof the salt actually absorbs carbon dioxide. It is clear, therefore,that if all the carbon dioxide from the tissues arrives in the lungsas bicarbonate, there must be some mechanism to secure its evolu-tion from the salt.It has long been taught in explanation of the familiar fact thatintact blood gives up the whole of its carbon dioxide to a vacuumthat the proteins play a part as weak acids, and it has been implied,perhaps more vaguely, that they play a similar part when thebicarbonate of the blood is exposed to the carbon dioxide tensionof the lungs.Evidence has recently been brought forward,ll horn'-ever, which throws doubt on their capacity to act in this way eitherin the former case or the latter.The special case of haemoglobin must, however, be considered,and from t>wo points of view. I mentioned in my last Report thestatement that h o g l o b i n has special properties as an ampholyte,acting as a buffer to it degree of which the plasma proteins are in-capable, and also becoming more acidic on passing from the reducedto the oxygenated condition.12 Hmoglobin itself also enters intocombination with carbon dioxide, the compound becoming lessstable with increasing tension of oxygen.13 Oxygenation in thelungs therefore drives out carbon dioxide from its combinationwith blood pigment, and also, independently, causes an increase ofhydrion concentration within the corpuscles.The corpuscles are,however, permeable to anions, and changes of equilibrium begunin the corpuscles extend to the plasma. In these facts we havea basis for explaining, a t least in part, the removal of carbondioxide from bicarbonate in the lungs. The direction of thesechanges must be reversed in the tissues where carbon dioxidetension is much higher and the oxygen tension nil. The inform-ation available, however, although becoming much more quanti-tative than before, is not yet quantitative enough for measuringthe relative importance of this or that factor, nor to give a completepicture of carbon dioxide transport.lo G. A.Buckmaster, Proc. phySi02. LC(OC.. J . Phydol., 1918, 52, xvi.l1 G. A. Buckmaster, J . Phy&oZ., 1917,51, 105.l* Ann. Report, 1917, 178.lb J. Christiansen, C. G. Douglas, and J. 8. Haldme, i&$d., 1914, 4$, 244 ;A., 1914, i, 1012148 ANNUAL REPORTS ON THE PROGR.ESS OF CHEMXS'J'RY.It is surprising, perhaps, that. in so fundamental a matter physio-logical knowledge should be yet to seek. As a matter of fact,however, as I claimed in a recent Report, the advances of recentyears towards an understanding of equilibrium in the blood havebeen remarkable, and progress continues. Yetl the teaching, as Iremember it, of twenty-five years ago was not wrong. As a sketchit was correct. We are now filling in the details of the picture,and the details are difficult.It is necessary that we should know more of the properties ofemulsoid colloids.Just as the gain in the purely chemical know-ledge of the composition of the proteins has helped to illuminatemetabolism, so, I think, will more knowledge of the physical-chemical properties of native proteins in solution throw light onsuch pheiioniena as those just discussed. Hence the importance ofSorensen's new work on the emulsoid colloids, which possess somuch more reactivity than the better understood suspensoids.Son7e Other Belations the Blood Proteins.A few other points cowenling the blood proteins may now bementioned. It" is likely that, as Hardy's pioneer work suggested,the condition of the euglobulins (not the pseudqlobulins) differsfrom that' of the albumins in coming nearer to suspensoid than t oemulsoid dispersion. It seems t.0 partake of the qualities of both,and the globulin system illustrates the point insisted on byGraham, and recently by Soremen, that many gradations can befound between a mere suspension of particles and true crystalloidsolution. Since we now know that the globulins really differchemically from the albumins, their relative fluctuations in theblood become of n o small interest.The ratio has been redeter-mined recently, and it seems to be constant in the same individualwhile in normal health, but differs widely in different individuals,the albumin fraction varying from 55 to 85 per cent. of the wholeproteins, and the globulins, including, of course, the pseudo-globulins, from 45 t o 70 per cent.Injecting foreign proteins hasno permanent effect on this ratio, which is rapidly readjusted.14There is, however, a large relative increase in the total globulinsduring injections of diphtheria or tetanus antitoxins.15 Fibrinogenas a special globulin is greatly increased by a first injection ofpeptone, but markedly depressed (negative phase) by a secondinjection a t the right interval. The injection of vaccines, tuber-lC Esther Smith and C. L. A. Smith, J . Immun., 1917, 2, 343.l5 TC . F. Mej7er, S. H. 1~urwitz, and 1,. Tenssig, J. h?fcc. Dia., 1918, 22, 1PHYSlOLOClCAL GhEM ISTRY. 3 49culiu, etc., increases fibrinogen.16 Older observations had sug-gested some of these recent findings.Whether these factorsincrease the globulin fraction by causing transference of proteinfrom the tissue to the blood, or in some other way, the increase isa n interesting point. The suggestion made some time ago that theeuglobulins represent protein-phosphatide complexes seems t o beconfirmed in various papers since published. This should beremembered in conliexioil with the discussion of phosphorus com-plexes in a later section. The distribution of phqhorus, organicand inorganic, in the blood is now being carefully studied.17Citwnzlica7 Factors i n Shock.I have referred to the successful use of gum arabic solutions inthe treatment of circulatory failure due to shock. An rrnderstand-ing of the factors concerned in producing * ‘ shock * ’ has been oneof the great needs of war-time, and much excellent contemporaryresearch has been done under the stimulus of that need.Meta-bolic chemical factors are suspected of playing a part, in producingshock, and although this aspect of the subject has proved elusive,the studies made deserve reference. Some of the facts elicited arerelated to those dealt with a t the end of the last section, andextend somewhat the ground covered by the discussion on thealkali reserve of the blood in last year’s Report-.Rather more than a year ago, observations made 011 woundedsoldiers in France were thought to suggest that ‘* acidosis,” definedas a serious reduction in the alkaline reserve of the blood, is acausative factor in the production of shock.18 It? was believed fora time that lactic acid, produced i n the injured moribund muscles,was the cause of this acidosis, so that a 17ery simple chemical factorseemed to relate the receipt of a severe wound with the subsequentcondition of shock.This conception, however, did not survive adiscriminating experimental study of the matter.19 When certaindisturbing factors had become understood and were eliminated, itcould be shown that a reduction of the alkali reserve of the blood,even if severe and long maintained, does not C S U S ~ shock. Nordoes it, indeed, cause any perceptible impairment of the circula-tion or any observable symptoms of importance. This conclusionG. Modrakowski and V. Orator, Wien. Med. Woch., 1917, 30, 1073.l7 J .Feigl, Biochem. Zeitsch., 1917, 83, 81 ; 84, 231 ; 87, 237 ; A , , i, 50,I* A. Wright and Fleming, L m c e t , 1918, i, 205.203: 357.Med. Res. Committee, Repwts of the Special Investigwtion Committee onSu.v&al Shock and Allied Conditions, No. 7, Acidosis and Shock150 ANNUAL REPORTS ON THE PROGRESS OF CHEMtSTRY.is one which might well have been expected, because it was alreadyknown that the alkali reserve might be greatly reduced withoutany increase in the hydrion concentration of the blood, and it isonly on changes in the latter that, theoretically a t least, we shouldexpect symptoms to supervene. The laborious experiments under-taken to establish the point would perhaps never have been donesave for certain mistakes in the interpretation of the earlier ex-periments.That these mistakes were made is no matter for regret,for the work done in consequence has yielded some quite interest-ing results and has shown, incidentally, that the Van Slyketechnique fur the estimation of alkali reserve is a trustworthy andconvenient aid to clinical observation.It has been thoroughly established by the experiment,al workreferred to that a grave depletion of the alkali reserve is indeedinvariably associated with such conditions as shock, but as asecondary result and not as a primary factor. It follows ondeficiency in the oxygen supply to the tissues, which itself resultsfrom the failure in the circulation. With lack of oxygen, theaccumulation of (lactic) acid in metabolism inevitably involvessuch a result.This, again, is by no means an unexpected revela-tion, but it is satisfactory to have such complete experimentaldemonstration of this objective change in the body occurring as aresult of deficiency of oxygen. As I endeavoured to emphasise intho last Report, observations show that although an individual inwhom the alkali reserve is diminished may display no symptoms,because the actual chemical reaction of his blood may be unaffected,he is yet in a different position from one who has a normal alkalireserve. . The former may become perceptibly dpspneic on slightexertion, and more intensely dyspnceic with an equally great exer-tion than the latter. This fact has been very fully demonstratedin these recent studies.The effects of want of oxygen have, infact, dominated what may be termed war physiology. The studyof these effects became necessary in connexion, not alone with shock,but with the results of gassing and the reaction of individuals tohigh altitude flying. Many interesting details have been added toour knowledge of the results of oxygen deficiency as a result, ofthese war studies.The investigations into shock have yielded results of generalinterest, some of which may be mentioned. The parallelism whichobtains between degrees of reduction in the blood-pressure andthe consequent fall in available blood-alkali is striking enough, nomatter how the former may have been brought about. There isa critical pressure above which no effect on the alkali reserve is t obe dmmmd- This, in the case of human beings, as well as oPHYSiOLOGlCAL CH EMLSTRY. 151and cats, lies in the neighbourhood of 90-80 mm.of mercury.Thus, taking a mean of a number of clinical cases, a t a bloodpressure of 90-100 mm. the carbon dioxide capacity (whichmeasures the alkali reserve) of the plasma was 49 ~01s. per cent.A t 60-70 mm. it was 36 vols., and a t 56-60 mm. only 24 vols.per cent.Not only does the mere existence of acidosis fail in itself to pro-duce shock, it has no effect in favouring the production of shockby other agencies. It does not exaggerate, for instance, the effectsof hamorrhage. The functions of the vaso-motor centre in main-taining the normal blood pressure remain normal in conditions ofacidosis.Acidosis does not modify the action of adrenaline northe " shock " effect of peptone or histamine.20Mention of the last substance introduces what remain the mostinteresting possibilities relating to the play of chemical factors inshock. It is well known that histamine (8-iminazolylethylamine)in large doses produces symptoms astonishingly like those ofanaphylactic shock, and the latter has many features in commonwith surgical shock. A paper dealing with a detailed study of thevaso-dilator effects of histamine has appeared during the year.21The action of the base would seem to be on the capillaries ratherthan on the arteries or arterioles, and the fall of pressure insurgical shock is almost certainly due to a similar capillary dilata-tion.The probability that metabolites with an action like that ofhistamine are normally formed during the activity of the tissuesis very great, and forms the readiest explanation of the capillarydilatation which accompanies increased activity.22 There is some-thing more than a possibility that such substances appear ingreater amount in damaged tissues, and the universal capillaryrelaxation which is a central feature of shock, although certainlynot an effect of acid production, may yet be due to the absorptionof histamine-like substances produced in extensive wounds.Biochemistry of Gumdine Compozcnds.I devoted a short section in my last Report to the action ofguanidine in producing the symptoms of tetany. The subject isof great interest and importance, and has progressed somewhatduring the year.That guanidine as a drug stimulates muscleshas been long known.% That in strong doses it produces, on theSo Med. Res. Committee Report, loc. cit.*l H. H. Dale and H. N. Richards, J . Physiol., 1918, 52, 110.a* CompareJ. Bsrcroft and €3. Piper, ibid., 1912, 44, 350 ; A., 1912, ii, 782.aa Gergene and Bmimann, PfEiiger's Archiv, 1876, 42, 206other hand, a curare-like action in frogs, and that, being stronglydissociated in solution, its action is that of a powerful base actingin the form of an organic cation, has been known since 1907; soalso has the fact that its physiological action is counteracted bycalcium salts.24 A little later it was shown to produce two effectsin muscle, one displayed in spontaneous twitching, the other in amodified response to nerve stimulation.It was suggested that itacted on two different substances in the muscle.?;' Meanwhile, thebase, methylguanidine, had been shown to be present in smallamounts as a normal constituent of muscle,26 and also found innormal urine.27I n 1912-1913, the methylated base was shown t o be pre-sent in much more than the normal amount in the urineof dogs which had undergone parathyroidectomy. If after thisoperation methylguanidine showed less increase, other guanidinebases, guanidine itself, for instance, and dimethylguanidine, weresaid to take its place. In connexion with the statements made inthe last section, it is of interest to note that histamine was alsoidentified in the urine of dogs which had nnciergone the operation,although only in three cases out of six.I n a discnssion of theabove findings, the suggestion was made that, the guanidine basesare responsible for the symptoms displayed after loss of the para-thyroids, but not with definite reference to tetany.28Then (1917) followed the clear experimental proof referred toin the last Report that guanidine bases were greatly increased inthe blood and urine both of clinical cases of tetany and of para-thyroidectomised dogs, together with the demonstration that theeffect of administering panidine is to produce symptoms identicalwith those seen after removal of t.he parathyroids.29 This year, theidentity of effect has been still further established by the proofthat the hypoglycania which is characteristic of a loss of the para-thyroid function is also produced by the administration ofguanidine salts, and, no less, the equally characteristic acidosisand increased excretion of ammonia.There would seem to be onepoint of difference, however-in the case of the rabbit, a t any rate24 H. Fuhner, Zefit?'. Physiol., 1907, 20, 838 ; A., 1907, ii, 901.26 M. Camis, J . PhysioE., 1909, 39, 73 ; A., 1909, ii, 819. See, for moreO6 R. Krimberg, Zeitsch. pkyysiol. Chem., 1906, 4$, 412; A . , 1906,27 F. Kutscher and A. Lohmann, ihicl., 1, 422 ; 49, 81 ; A., 1906; ii, 471,2sF. W. Koch, J . BioE. Chem., 1912, 6, 451; 1913, 15, 43; A., 1912,2 9 Quart. J . exp. PhyRioE., 1917, 10, 175 ; Ann. Rcpo~t, 1917, 195.recent work on this point, J.S. Meighan, ibid., 1917, 51, 51.ii, 781.786, 875.ii, 1194; 1913, i, 735PHYSIOLOGICAL CHEMISTRY. 163-in that, unlike the btany induced by removal of the glands, thatwhich follows guanidine administration is notl abolished by givingcalcium sa1ts.m Such a contrast may depend, however, on no morethan the inevitable difference of conditions involved in the directadministration of the base on the one hand and its gradual pro-duction in the body on the other. Another phenomenon which isseen in the absence of the glandular function, and results also fromguanidine injection, the arrest, namely, of the vago-cardiac in-hibition, has been shown to be removed in each case by givingcalcium salts.s1The proof thhatr the action of guanidine is responsible for sofamiliar a pathological condition as tetany, and the possibility thatthe pathological action is simply an exaggeration of a physiologicalfunction, certainly make the whole question of guanidine meta-bolism a very interesting one.We want t.0 know how t o relatetogether, in terms of metabolic change, arginine, with its guanidinenucleus, the guanidine bases themselves, and creatine with itsmethylated guanidine grouping. The extraordinarily elusive func-tions, or meaning in metabolism, of the last-mentioned substancenow gain renewed interest.It seems likely enough that both guanidine and creatine arisefrom arginine, although I do not feel that the point is actuallyproven in either case.It was to be expected, perhaps, thatguanidine takes its direct origin from creatinine, but as after para-thyroidectoiny the free guanidine of the muscles decreases and thecreatine increases more o r less proportionately,3” there is some sug-gestion for the reverse relation. Maybe there is only a shift. ofthe equilibrium which exists between them.An endeavour to answerthis question formed the last as well as some of the earliest scien-tific work of W. H. Thompson,s to whose tragic death I earlierreferred. He administered arginine carbonate, by the mouth orby injections, to ducks, dogs, and rabbits. On a diet free frompre-f ormed creatine, the only safe condition for experiment,administration by the mouth of 3 grams of the arginine salt todogs gave an average extra excretion of 23.6 milligrams of creatine,estimated as creatinine (pre-formed creatinine was not usuallyaffected), in the urine, corresponding with an increase of 10 percent.in the daily output of creatinine, and representing about2.5 per cent. of the guanidine nucleus of the arginine given.so C. K. Watanabe, J . Biol. Chem., 1918, 33, 263; 34, 61, 66, 73; A.,i, 205, 327.32 P. S. Henderson, ibid., 1 ; A., i, 279.38 W. H. Thompson, ibid., 1917, 51, 111, 347 ; A., 1917, i, 673: 1918,Does creatine arise from arginine?81 D. Burns and A. M. Watson, J . Phydol., 1918, 52, 88.i, 88154 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRYApproximately the aame results were given in the case of birds,Somewhat larger increases, amounting in dogs to 22 per cent.ofthe normal excretion of creatinine, were found after hypodermicor intravenous injection. It is remarkable that a second adminis-tration did not show the effect. It is remarkable, too, that a largerpercentage of the guanidine nucleus seemed to appear as creatinewhen racemised arginine was given.Estimations of creatine in the muscles of rabbits were madebefore and after injections of from 1.5 to 3.1 grams of argininecarbonate, the muscles of the one limb being removed before theinjection, and those of the corresponding limb on the opposite sidesix hours after it. Possible changes in water content during theexperiment were controlled.The results were all consistent (seven observations) in showinga higher percentage after arginine injection, but the increase wasvery small.I n one experiment, it is true, the creatine was in-creased by 8 per cent., but in two by only 2 per cent., and on theaverage by only 3 per cent. I n later experiments, the argininewas given in company with substances which were presumed ableto supply a methyl group for the methylation of the guanidinenucleus, for instance, methyl citrate and methyl benzoate. Theformer of these seemed definitely to increase (on injection, notafter feeding) the amount of creatine formed from a given amountof arginine, whilst the latter had no such effect. With methylcitrate, after correction was made for the rather noteworthycircumstance that this substance when administered alone gavesome increase, the plus excretion was found to account for 7 percent.of the guanidine nucleus in the arginine injected. Experi-ments in which the arginine was combined with betaine or cholinedid not show that this type of methylated compound increased thepower of the arginine to affect the urinary creatine or creatinine.Much larger increases were seen when, with the arginine, para-formaldehyde or hexamethylenetetramine was injected into ducks,but an increase nearly as large followed the administration of theformaldehyde aIone, so there was no proof that the arginineadministered a t the time was converted into creatine. If form-aldehyde, in whatever way, really increases the production ofcreatine on synthetic lines, it is a noteworthy fact.We have tothink, however, of the possibi1it.y that a toxic breakdown of musclesubstance may be responsible for the increase. Thompson himselfsuggests that the reactions involved are those which form the basisof Werner’s theory of the methylation of amino-compounds byf ormaldehyde.3433 W. R. Thompson, Biochem. J . , 1917, 11, 307; A,, i, 142PHYSIOLOGICAL CHEMISTRY. 155The injection of guanidine carbonate increased the total urinarycreatinine to a degree which would indicate methylation of some10 per cent. of the base administered. It does not seem certain,however, that. Folin's method, which was used for the estimations,might not return as creatinine some other derivative of the injectedguanidine.It seems to me that this very laborious and praiseworthy experi-ment'al study (of which the accounts abound in detail), whilst mostcertainly adding strength to the probability that creatine arisesfrom arginine, cannot be said altogether to prove that i t does SO.Other recent observations 35 have been made on somewhat similarlines, although involving very few experiments.In one experi-ment, the injection of 2 grams of arginine increased the urinarycreatine (expressed as creatinine) of a dog from 6.4 to 16 milli-grams without affecting the pre-f ormed creatinine. The autborsattach no importance to this result, because an injection of histidinecarried out as a control produced a similar effect. In so arguing,they neglect the fact that arginine and histidine have been shownto be largely capable of replacing one another in metzabolism.36However, in a second experiment with arginina the effect was notobtained.I have ventured elsewhere37 to point out that.experiments of thekind just noticed do not necessarily give favourable conditions forproving whether a given reaction in metabolism starts initially fromthis or that substance. Knowing, for instance, as we do, that thecreatinine of the urine is practically unaffected by the widestvariations in the protein intake, and is therefore independent ofthe amount of arginine absorbed during digestion, we shouldscarcely expect it to be affected by an increase in the supply ofarginine given in free form. Creatine itself might be formed andyet not be excreted. Nor is it likely that the latter would in anycase be appreciably increased in the muscles under such conditionsas those described.When an animal is in a state of adequatenutrition, it does not follow that a. particular process in its tissueswill be appreciably affect?d by a mere increase, and especially avery temporary increase, in the supply of the precursor from whichthe process normally starts. Otherwise, there could not be thatdistinction between endogenous and exogenous metabolism whichis usually recognised. Of the relative stability of the former,creatinine is the most conspicuous example. The tissue cell as as6 L. Baumann and H. M. Hines, J . BioZ. Chem., 1918, 35, 95 ; A., i, 417.s6 H. Ackroyd and F. G. Hopkins, Biochem. J., 1916, 10, 551 ; A . , 1917,i, 237.H.Ackroyd and F. G. Hopkins, Zoc. cif156 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.chemical system does not, of course, escape from the laws of chem-istry: an increase in. loco of the concentration of specific materialmust accelerate the reactions which that material normally under-goes. I n some cases, such, for instance, as that of urea formationfrom amino-acids, we find an immediate effect from an increase inthe concentration of the precursors. This, indeed, is the realcharacteristic of whatl we call exogenous metabolism. In the caseof reactions which are part of the basal and essential, as distinctfrom the more accidental (often self-protectlve), activities of atissue, the velocity is much more independent of the supply of rawmaterial, because, owing t o the organisation of the cell, any excessdoes not arrive a t the locus of that particular change.The excessis got rid of by other less specific reactions, hydrolysis and directoxidation, for example (exogenous change), and has but a tem-porary existence in the cell. That, some regulating mechanism can,as it were, be forced by a large increase of concentration round thecell, may possibly account for small changes such as the increaseof creatine in the above experiments.Other papers dealing with creatine and creatiinine from aspectsdifferent! from the above have appeared during the year. Onlyone, I think, calls for notice. To test once more the question of asupposed relation between creatine and carbohydrate metabolism,advantage was taken of the fact tjhat in ruminants creatine isnormally excreted as well as creatinine.I n these animals, it wasfound that the excretion of the former is in inverse proportion tathe amount of carbohydrate in the diet'. It is plausibly arguedfrom the evidence given that ci-eatine is produced in metabolism inrelatively large quantities, that it is utilised in the tissues, and thatits utilisation is intimately connected with the metabolism of carbo-hydrate. So far as the conversion of creatine into creatinine isconcerned, it is suggested that when the former is produced withinthe metabolic field, it is probably in a more favourable positionfor such conversion (if this takes place) than is creatine given bythe mouth or by injection. The amount converted depends onsome metabolic process which is not affected by the amount offeredfor conversion.% This point of view is, clearly, the one which Ihave myself urged-in more detail and with less caution-in thepreceding paragraphs.38 B.Qrr. Biochrm. J . , 1918, 12, 221 ; A., i, 561PHYSTOLOQICAL CHEMISTRY. 157The Phosphoric A cid Comfleses of Livinny CeLl8.Since, in 1911, Professor Halliburton39 gave an account of re-search done on nucleic acids, these important substances havereceived no attention in these Report.. The work of the Rocke-feller Institute towards the end of the last decade extended theresults of the earlier studies and left our knowledge of &hymus-iiucleic acid in a satisfactory state, although there is still un-certainty about the details of its inolecular structure.40 Of late,attention has been given rather to yeast-nucleic acid.No evidencehas yet appeared t o shake the general belief that the nucleic acidsof all animal cells are identical with the former substance,ll andthose of all vegetable cells with trhe latter. The two nucleic acidsare therefore exceedingly widespread in nature and of great hio-chemical importance.In an interesting address, P. A. Levene4? has remarked thatsuch apparent lack of differentiation in the nuclear material ofliving tissues was scarcely to be expected. It removes part of theevidence for the view that underlying the morphology of speciesis a chemistry of species. There are, however, countless otheropportunities in the cell for chemical variation.The uniformityof the nucleic acids would seem to point to the factl that theirstructure is something fundamental to the make-up of the cell--something essential to the life of all tissues.It will be recalled that the essential chemical structure of thenucleic acids is that of polynucleotides. In the simplest type ofnucleotide-the mononucleotide-orthophosphoric acid is condensedwith a carbohydrate and a purine or pyrimidine base, the carbo-hydrate residue being intermediary, linking the acid to the base.Such are guanylic acid (phosphoric acid-d-ribose-guanine) , firstisolated from the pancreas, and iziosic acid (phosphoric acidd-ribose-hypoxanthine) from muscle. These mononucleotides, how-ever, are not found as such in the nuclei of the cells, but are to belooked on rather as met.abolites of the true nucleic acids, and, soss Ann, Report, 1911, 199.4O For literature up to 1913, see “ Nucleic Acids : their Chemical Propertiesand Physiological Conduct,” by Walter Jones.Longmms, 1914. Mono-graphs of Biochemistry.41 See, however, R. Nakasako, (‘ Nucleic Acid of the Lymph Corpuscle.’ ’ A. C.James Remarch Lab., 1917, Bull. 3, 29 (Physiol. Abstr. 1918, 3, 4). I havenot eeen the original of tfhis paper. The author claims to have isolatedxanthine and hypoxmthine t~ well as gua4idine and adenine. All previousexperience would suggest that enzymic deamination had occurred before OFduring the preparation of the material.42 J . Amer.Chem Soc., 1917,39, 8 2 8 ; A., 1917, i, 363158 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTEY.far as the two just mentioned are concerned, as being probablyderived from vegetable food consumed by the animal.Six years ago it was well established that in thymus-nucleicacid four different mononucleotides, containing respectively thebases adenine, guanine, cytosine, and thymine, are linked together.Less certain is the exact grouping of these four constituents of themolecule and the nature of the linkings, although the structuralformula suggested by P. A. Levene has met with general if onlyprovisional acceptance.@For a considerable time there has been t-he suggestion that yeast-nucleic acid is also composed of four mononucleotides linkedtogether, the difference between the vegetable and the animal pro-duct being that in the former the carbohydrate of each group isd-ribose instead of a hexose (see below), whilst a uracil-mononucleo-tide replaces the thymine-mononucleotide.Recent work has provided confirmatory evidence for the exist-ence and nature of the four mononucleotides, and nothing hasarisen to suggest that the molecule of yeast-nucleic acid containsany other essential element in its structure.From the productsof its partial hydrolysis, guanylic acid,4* as well as uridine-phosphoric acid (uracil mononucleotide), and cytidine-phosphoricacid (cytosine mononucleotide), have been prepared pure, whilstthe fourth nucleotide, containing the adenine group, has also beenseparated with a reasonable guarantee of purity.45In the case of the vegetable nucleic acid, however, there is, evennow, less evidence for the actual grouping of the mononucleotideconstituents and for the position of the linkings than can beclaimed in the case of the animal product.The effort to get theevidence has naturally been made on the lines of studying the pro-ducts of carefully limited hydrolysis. It was the isolation of suchproducts-dinucleotides, for example-which threw light on thestructure of thymus-nucleic acid.It has been recently stated that yeast-nucleic acid, either byenzyme hydrolysis 46 or, more simply, by heating with ammonia,47could be made to yield two intact dinucleotides, the one contain-ing adenine and uracil, the other guanine and cytosine.It wasfurther claimed that from the products of controlled hydrolysis byacids a third dinucleotide containing cytosine and uracil could be48 P. A. Levene and W. A. Jacobs, J . BioZ. Chem., 1912,12,411 ; A., 1912,44 B. E. Read, ibid., 1917, 31, 47 ; A., 1917, i, 696.46 P. A. Levene, ibid., 1918, 33, 229, 426; A., i, 130, 240.47 W. Jones and B. E. Read, ibid., 1917,29, 111 ; A,, 1917, i, 232.i, 926.W. Jones and A. E. Richards, ibid., 1915, 20, 25; A., 1915, i, 91PAYSlOLOGICAL CHEMISTRY. 159separated.a This evidence, if established, would clearly indicatethat the two pyrimidine mononucleotides are linked together andtake the central place in the original molecule, whilst the con-stituents containing purines would be external, the adenine mono-nucleotide being attached to the uracil mononucleotide and theguanine mononucleotide to the cytosine mononucleotide.More-over, because the supposed dinucleotides appeared to yield brucinesalts containing four molecules of the alkaloid, the suggestion arosethat the phosphoric acid hydroxyl groups could not be, as wasformerly supposed, concerned in the linking of one mononucleotideto another. The linkings would then most proba,bly involve thecarbohydrate groups, and 8, tetraribose of the structurewould form, as it, were, the essential nucleus of the nucleic acidmolecule, which would be in effect, a substituted polysacchariderather than, as in the earlier view, a substituted phosphoric acid.Theproducts supposed to be dinucleotides, although they gave con-sistent analytical figures and cryptalline brucine salts, of which thecomposition remained constant during repeated recrystallisationfrom methyl alcohol, and also barium salts to correspond, werenevertheless apparently mixtures.By the choice of a specialsolvent-dilute (35 per cent .) ethyl alcohol-the brucine salts couldbe in each case separated into two fractions. From each of thesewas obtained a mononucleotide containing one of the two basessupposed to be in the corresponding dinucleotide.49It has beenclaimed elsewhere that with controlled hydrolysis by enzymes orweak ammonia, the uracil mononucleotide may be split off, leavingintact a trinucleotide containing the three remaining bases.60 Thisclaim was first based on the preparation and analyses of a hexa-brucine salt of the supposed trinucleotide, evidence which wasrightly criticised as unsatisfactory and insufficient.The trinucleo-tide, however, has now been further studied51 and made to yielda dinucleotide containing guanine and adenine. This, as well asthe cytosine mononucleotide simultaneously split off, was obtainedin a crystalline form. There would therefore seem to be now goodevidence for the existence of the trinucleotide from yeast-nucleic(C,H,oO,h - 3H2OUnfortunately, this evidence seems to have broken down.So far I have been dealing with American work.48 W. Jones and B. E. Read, J . Biool. Chern., 1917,31, 39 ; A., 1917, i, 596.O8 P. A. Levene, ibid., 1917, 31, 691 ; A,, 1917, i, 670.Levene, Zoc. cit.6o S . J. Thannhauser and G. Dorfmiiller, Zeitach. phy8iOl. Chem., 1917,swpra.100, 121 ; A., i, 49.S. J. Thannhauser and G. Dorfmiiller, Ber., 1918, 51, 467 ; A., i, 316160 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.acid, and for the particular grouping which its compositiunindicates. The two purine nucleotides would appear to be adjacentin the original nucleic acid molecule.I n the trinucleotide, six hydroxyl groups belonging to the phos-phoric acid radjcles are free, so that the linkings probably involvet.he Carbohydrate groups. It would seem, moreover, that the threeconstituents of the trinucleotide must have a linking different fromthat which holds the uracil nucleoticle in the molecule, since thelatter is more easily eliminated by hydrolysis.The suggestion istherefore put forward thatJ whilst in the original nucleic acid allfour nucleotides are joiijed through the phosphoric acid groups,the three present in the t.rinucleotide have additional linkingthrough the carbohydrate groups. Hydrolysis with diluteammonia severs only the linking between the phosphoric acid!groups.As iswell known, the existence of the hexose grouping in this has beenaccepted on indirect evidence. The sugar has not. been isolated,but its nature has been inferred from the yield of lzvulose andformic acid on hydrolysis. It is now stated 52 that the “carbo-hydrate ” is really related to ghcal (C,H,,O,), a reduction productof glucose first described by Emil Fischer in 1913.It is to behoped that so important a statementl will be duly tested by thosewho are now working a t the chemistry of nucleic acids.It is clear that recent work on the constitution of these cellconstitnuents has brought. us no evidence of a final sort, but I havefelt justified in dealing with it a t some length because the papersquoted illustrate a gradually developing technique for dealing withwhat are difficult but, biologically, very important chemicalproducts.The nucleotide structure, of which there is no doubt whatever,is essentially remarkable. One feels how unlikely itl is that purechemical suggestion would by itself have led to! the idea of theexistence of natural compounds in which a carbohydrate linksphosphoric acid t o a base.Yet1 it is now certain that such com-pounds play a prominent part in the chemistry of living tissues.Their synthesis should tempt the chemist.One may remark that yeastrnucleic acid, being extensivelyemployed in medical and surgical practice, is now prepared in thiscountry on a commercial scale.53 I f the product prove to be fairlypure and free from the products of its own partial hydrolysis,5% R. Feulgen, Zeitsch. phy&oZ. Chem., 1917, 100, 241 ; 1918, 101, 296 ;A., i, 85, 413.63 Compare A. C. Chapman, Analyst, 1918, 9-3, 269.A brief reference may be made to thymus-nucleic acidmaterial for further research has beconic easy to obtaiii. ripartfrom this, we now possess a relatively easy method for preparingit in the lab0ratory.5~Brief reference may iiow be made t o allied tissue constituents,the phosphatides, Because of the diff ereiice in their geographyin the cell, and maybe because of t.he differences in their probablefunctions, but chiefly, I think, because of the accident of.widelydifferent solubilities, nucleic acids aiid phosphat.ides are usuallythought of apart. From the point of view of intermediary meta-bolism, however, it is a mistake t o forget the circumstance thatwhilst the former comist of phosphoric acid in association with abase and carbohydrate, the latter contain phosphoric acid associatedwith a base aiid a fat. The resemblances and the differencesin t.he chemical make-up of these subst8aiicej are alike sugges-tive.A summary of t,he difficult and scattered literature of the phos-phatides has appeared diiring the year in a monograph by1%.Maclean.55 The book, as the author points out in his preface,was written in circumstances lnade difficult by the war. It’ is,nevertheless, most valuable as an up-to-date account; of presentknowledge concerning the phosphatides and lipins. It also containsjust criticism of much literature which does not represent know-ledge. The author emphasises once more, whatq even Germanwriters have of late a l l o ~ e d , that. although our lriiowledge of thelipins has been materially increased within the last few years, wereally know little to-day beyond what was known and publishedby Thudicum more than twenty years ago. “Indeed, recentadvances are in many cases but corroborations of Thudicum’swonderful experimental work.”I propose t o refer only to some advances iu coniie,Yion with thepurification and characterisation of the chief exemplar of the phos-phatide group-lecithin itself.Until certain observations byillacLean 66 were published, most preparations of lecithin acceptedas pure were probably really mixtures in which true lecithin, ofwhich the basic constituent is choline, was associated with therelated substance kephaliii, which contains aminoethyl alcohol asa base. It was shown that a separation was possible by treatingt’he mixed cadmium chloride compounds with ether. The absenceof kephalin from a preparation can be demonstrated with ease,because, unlike choline. its base contains an amino-group, and64 G.Clarke and S. B. Schryver, Biochetn. J., 1917, 11, 319 ; A., i, 130.65 “ Leoithin and Allied Substances ; the Lipins.”56 H. MacLean, Biochem. J., 1915, 9, 357 ; A . , 1915, i, 936.REP.-VOL. XI7. aMonographs on Bio-ohemistry, 1918 : Longmans62 ANNUAL REP’ORl’S OX THE PROGRESS OF CHEM1S’I‘K.y.therefore yields nitrogen in Van Slyke’s apparatus. Further workin this connexion has been published during theIf the cadmium compound of “ lecithin” from egg-yolk is r ecrystallised from a mixture of ethyl acetate and 80 per cent.alcohol, the true lecithin can be freed from kephalin and thenliberated from its cadmium compound by means of ammoniumcarbonate. If, atany rate, it is reduced by hydrogen in the presence of palladium,so as to give the corresponding hydrolecithin, in which both of thefatty acid radicles are saturated, elementary analyses then agreevery exactly with theory.Reduced kephalin-hydrokephalin-in which the two fatty acid residues are present as stearyl, hasalso been prepared so as to give theoretical figures on analysis.It will be noticed that this satisfactory guarantee of individua1it.yis attached to preparations which have been, so t o speak, stabilisedby the reduction of unsaturated fatty acid radicles contained inthe phosphatide.Quite apart from the instability displayed during the course oftheir extraction, the difficulty of preparing individualised sub-stances of this type is, in my opinion, only to be fully understoodby recognising that part a t least.of the metabolism of normal fat,and probably some of the metabolism of carbohydrate, proceedwithin these phosphorus complexes.The condition of things in living stuff is never statical-there israther, so to speak, dynamic equilibrium. Reactions run insuccessive stages : a t first, maybe, in synthetic directions, butultimately towards end-products which are excreted. These reac-tions are constantly maintained by a supply of new material fromthe food.From such a milieu, a chemical individual can be isolated withease only if, in the series of changes, it happens to be a phasewhich tends to accumulate.58 Intermediate products whichaccumulate in relatively large amounts are those which areresponsible for the physico-chemical properties of the cell-thosewhich we look on as part of its structure. Among such, doubtless,are certain of the phosphatides; but so long as the tissue is alive,the fatty acid radicles in the phosphatides almost certainly undergodesaturation and probably oxidation, whilst the molecule is a t thesame time continuously reconstructed from a fresh supply of fattySuch a preparation seems to be really pure.57 P.A. Levene and C. J. West, J . Biol. Chem., 1918, 33, 111 ; 34, 175 ;58 See on this point F. G. Hopkina, “The Dynamic Side of Biochemistry.”Nature, 92, 213 ;35; 285 ; A., i, 98, 288, 421.Addresa in Biochemistry, Rep. Bm’t. Assoc., 1913, 652.ale0 W. M. Bayliss, ‘‘ Principles of General Physiology,” 1st ed., p. 20PHYSIOLOGICAL CHEMIS‘I’RY. 163acids.When a main product is isolated, it is t-herefore likely tobe associated with small amounts of related products, and it is notsurprising that purification is difficult.The suggestion that fats may be metabolised when inphosphatide combinations is by no means new, but recentwork59 has given evidence for it on fresh lines. Thereseems, for instance, to be no doubtl thatl when ordinary fattyacids are being absorbed from the gut after a weal rich in fat,there is st marked increase of phosphatides in the blood, andespecially in the corpuscles of the blood. The corpuscles takeup a t least a proportion of the fat absorbed and build it upstraightway into phosphatide complexes. I n these, the fatty acidscertainly undergo desaturation.A further indication of theinstability of the phosphatides in metabolism is found in thepresence of a specific lipoidase in leucocytes and pus cells.60 Thisenzyme hydrolyses lecithin in feebly alkaline solution. It is morethennolabile than the ordinary lipase associated with it.It may be noted, in parenthesis, that another synthetic processoccurs when fats are being absorbed, for although the totalcholesterol in t h blood is unaffected by the taking of a fat dieh,bhe amount presentl in the form of its fatty acid esters is markedlyincreased during absorption. The cholesterol thus concerned inf a t transport seems t o be of the ordinary kind, cryst-allising inrhombic form, whereas in organs such as the kidney a differentvariety predominates, which crystallises in elliptical form .61What may be the significance of the co-existence of two methodsfor f a t transport-in phosphatide combination and in cholesterolesters respectively-is uncertain.It is clear, however, that thefacts just reviewed, together with the circumstance that a greatpart of true “tissue ’’ fat, as distinct from fat merely deposited,consists of phosphatides, give a very strong suggestion for themetabolic importance of the latter.Turning now in t.his same connexion to the fate of carbohydrate,it may be noted that there is accuniulating evidence for the beliefthat the precursor of lactic acid in muscle is sugar in the form ofa hexosephosphoric acid.G2 If this be the case, an important partof the whole metabolism of carbohydrate is associated with a phos-phorus combination.5 y W.B. Bloor, J . Biol. Chem., 1910,24,447 : -4., 1916, i, 450 ; A. Knudson,8o N. Fiessinger and R. Clogne, Compt. rend., 1917, 165, 730; A., i, 50.ibid., 1917, 32, 337; d., i, 136.I. Lifschutz, Biochem. Zeitsch.., 1917, 83, 18 ; A., i, 51.G. Embden and F. Laquer, Zeitsch. physiot. Chem., 1917,100,181 ; A.,1917, i, 674.a It would be a great, mistake, moreover, tasynthesis of hexosephosphoric acid during thefermentation of sugars is a phenomenon remoteconsidering.suppose t,hat thecell-free alcoholicfrom those we areSince the important observations of Harden and Young firstdirected attention to this fundamental phenomenon in 1905, muchwork has been done in coiinexioii with it! and there are some recentpapers to be noted.The coniposition attributed to the hexose-phosphoric acid by the above authors, C6H,,04P(P0,H,),, and thefact that it yields lsevulose on hydrolysis, have been confirmed.63The previously known circumstance that, although the substance isformed under the influence of yeast juice, living yeastl cells do notferment itl, has been shown to remain true even when added co-ferment and artificial activators are supplied. Moreover, whilstdried yeast, or cell-free yeast juice, in. the presence of sugarsesterifies added phosphates almost quantitatively, it is stated thatthe living cells, even when toluene has been added, may esterifyonly some 8 per cent. of the added phosphate. These facts haveled to the suggestion that the formation of the hexose-phosphatein cell-free or dead cell fermentations is a " pathological " process.64This suggestion seems to me unjustifiable and against the weightof evidence.It is far more reasonable to suppose that the wholequestion is one of cell permeability. I n the experiments, whichgave so small an esterification of phosphates, it is possible, more-over, that the excess of toluene used was deleterious. Again, inall work with yeasts, the part.icular strain chosen and its previoushistory must always be considered.65 It is stated, for instance, thatcertain yeasts when weakened by nitrogen starvation fail to esterifyphosphates in the presence of dextrose, but nevertheless esterifythem when laevulose is supplied.66 Other experiments, nioreover,have shown that when living yeast cells are acting on a mixture ofdextrose and phosphates, whilst there may be littde synthesis in theearlier stages of tlhe fermentation, the combination of hexose andphosphoric acid occurs rapidly during later stages.67 In this con-nexion, it is very interesting t o learn that an artificial sucrose-phosphoric acid is hydrolysed, and its sugar fermented, by livingyeast cells.68 This seems to me t o show that cell permeability playsan important.part in these phenomena.1917,83, 244 ; A,, i, 91.6s C. Neuberg, E. Flirber, A. Levite, and E. Schmsnk, Biochem. Zeitsch.,64 Idem, 2oc. cit.66 H. Euler, Biochem. Zeitsch., 1918, 86, 337 ; A., i, 329.66 H. Euler, H.Ohlsen, and D. Johmson, ibid., 1917,84, 402 ; A., i, 149.*? H. Euler, 0. Svanberg, G. Hdlberg, and K. Branding, Zeitsch. phyaiol.68 K. Djenab and C. Neuberg, Biochem. Zeitsch., 1917, 82, 391 ; A., 1917,Uhem., 1917, 100, 203; A., i, 54.i, 680P H Y S 10 LoGI (: A T, C H EM I STR Y . 165The Biochemicul Deyradatiou of Dextrose.Many references have been made in these Reports to investiga-tions dealing with the intermediary metabolism o€ dextrose in theanimal body and with the problem of determining successive stagesin its degradation. During the past year, work on the subject hasbeen more or less quiescent. TO.’ one statement, however, I shouldlike to direct’ attention.@ If dextrose solutions are, under suitableconditions, perfused through the pancreas, the optical dextrorota-tion of the perfusates is said to be diininished withoutl any altera-tion in their reducing power.Osazones from such perfusates havea lower melting point than glucosazone. It is supposed that thesechanges represent a preparation of the sugar for iiornial utilisatioii .Such experimental results may represent- nothing more than th coccurrence of condensation to a polysaccharide. on lines alreadysuggested by the work of Levene and Meyer and by that of Lom-broso.70 Whether this condensation really involves the formationof a phosphoric acid complex seems, by the way, not yet to havebeen considered. What, however, is of special interest in therecent work under notice is the circumstaizce that, unlike dextrose,lmmlose is noi; affected by perfusion through the pancreas.NowIzevulose is certainly well utilised in the body, and, under certaindiabetic conditions, better utilised, or at least more easily con-verted into glycogen, than dextrose itself. There seems, indeed, t%be just the suggestion that- lmdose is not affected by the pancreas,because it is already available f o r utilisation. One thinks, a t anyrate, of points discussed in the preceding section-of the fact thatthe carbqhydrate in hexose-phosphate, although produced by yeastjuice from dextrose, yields lmulose on hydrolysis; of the circum-stance that a weakened yeast, unable t o esterify dextrose, can yetdeal with laevulose. There appears, indeed, t o be an indication thatin certain circuinstances, a t any rate, the protoplasm can grip theketose structure more readily than the aldose structure, and thatpreparatory processes may be concerned with t’he conversion of thelatter into the former.It is certainly undesirable that those who seek for ;nformationconcerning animal metabolism should ignore the facts won fromthe study of the lower organisms.They may not be susceptible ofdirect application, but they may often afford suggestion andguidance. I propose to remark on some further studies of yeastwhich can be logically considered after those dealt with in the lasfsection.C B A. H. Clark, J. Exp. Med., 1917, 20, 721 ; A., i, 139.7 O Ann. Report, 1916, 214166 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Although probably no one doubts that a three-carbon compoundof some sort is an early intermediate product in the process ofalcoholic fermentation, lactic acid, since the work of Slator, hasbeen held to be out of court in this connexion.Only in thepresence of some added reducing substance (hydrogen acceptor),such as methylene-blue, are the conditions giveia for any appreci-able production of alcohol from this acid. The reductase of yeastcan with this assistance convert the lactic acid into acetaldehyde,which may itself suffer reduction to alcohol. Tn any case, theresults of quantitative studies are against the view t"hat lactic acidis a normal intermediary product.71 On the whole, it seems thatthe trioses must also be ruled out'. Neither glyceraldehyde nordihydroxyacetone undergoes fermentation with yeast..It has beenclaimed, indeed, that> the synthetic phosphoric ester already dis-cussed contains a triose group as well as a hexose group, but4 theevidence is far from conclusive.72 Trioses yield methylglyoxal ondistillation, whilst hexose-phosphoric acid yields none.On the other hand, the evidence to show that pyruvic acid is anormal intermediary in the productioii of alcohol seems to bestrengthening, even although we are ignorant of what standsbetween i t and the hexose molecule. The case in its favour clearlygrows stronger with the proof that acetaldehyde is formed by yeastin really considerable amounts, since it is well known that thecarboxylase of yeast rapidly converts pyruvic acid into aldehyde.By growing yeast in the presence of sodium sulphite, the proof isobtained.73The formation of pyruvic acid from sugar involves the removalof hydrogen under the influence of the yeast reductase, and for thecontinuance of this stage of the degradation an acceptor for thehydrogen is required; this acceptor has been assumed t o be acet-aldehyde itself, of which, as soon as i t is formed, a moiety is con-verted straightway into alcohol.From one molecule of sugar,therefore, any process involviiig partial arrest at the aldehydestage could yield a t the most one molecule of the aldehyde. Ofthe amount to be expected on this view, as inuch as 75-45 per cent.has been obtained by fermentation in the presence of sodiumsulphite.Of the importance of the aldehyde stage there can therefore beno doubt, but if we accept the above view of fermentation as awhole, we have to recognise that acetaldehyde, as well as being theCompare A.Lebedev, Biochem. J., 1917, 11, 189 ; A., i, 149.78 A. Lebedev, ibid., 1918, 12, 87 ; A., i, 364.'9 C. Neuberg and E. Reinfurth, Biochem. Zeitsch., 1918, 89, 365 ; d.,i, 617PHYSIOLOGICAL CHEMISTR\i 167immediate precursor of the alcohol, bas to initiate by its presencethe production of the very substaiice from which it itself takesorigin. It is clear, therefore, that some minimal amount of pre-formed aldehyde must be present from the first in any fermentingsystem. There at Once occurs t o the mind a particular possibiIity.Since the pioneer observations of Harden and Young, i t hasbecome fully established that when yeast juice is filtered ordialvsed, a factor necessary for fermentation passes into the filtrateor dialysate, the residue being incapable of fermenting sugar untilthat factor is restored.This factor is the so-called co-ferment.Is acetaldehyde this co-ferment, or is it present as a constituent ofthe cu-ferment8 system 1The presence of pyruvic acid would have identical significance,because the carboxylase of yeast is not removed by filtration ordialysis, so that the residue can still convert the acid into thealdehyde.It has been known for the last. three years74 that the additionof small amounts of pyruvates accelerates fermentation bymacerated yeast,. It is asserted,75 however, that neither yeast-juice nor zymin (acetone yeast), when once deprived of its CD-enzyme, is reactivated by pyruvates when these are added alone,not even when a proper supply of phosphates is present.Reactiva-tion calls, i t is said, for a mixture of keto-acids or their salts. Thisstatement has always been difficult t o understand, and to judgefrom recent work it does not seem to be true,76 although still main-tained by its originator.77 Zymin rendered inactive by thoroughwashing is, as a matter of fact, readily activated by potassiumpyruvate in the presence of a suitable concentration of potassiumphosphate. Acetaldehyde in similar circumstances also activates,and a great number of other aldehydes have been shown to do theIncidentally, it is interesting to know that potassium orammonium phosphate must be supplied in all cases; sodium phos-phate is quite ineffective.79There would seem from the facts so far before us to be goodgrounds for the belief that what is washed away during the in-activation of yeast preparations consists of such amounts ofpyruvates o r acetaldehyde as are normally present, in the yeast.74 M.Oppenheimer, Zeitwh. physiol. Chern., 1915, 93, 235; A., 1916,i, 358.75 C. Neuberg and E. Schwenk, Biochem. Zeitsch., 1915, 7 , 135 ; A., 1916,i, 1045.76 A. Harden, Biochem. J., 1917, 11, 64; A., 1917, i, 601.77 C. Neuberg, Biochem. Zcitsch., 1918,88, 146 ; A., i, 469.78 C. Neuberg, Zoc. cit.i 9 A. Harden, Biochem. J., 1917, ti, 64 ; A., 1917, i 50168 ,iNNUAL REPORI'S 0s THE PROGRESS OF CHEMISTRY.The * ' co-ferment " would thus represent no more than theseremainders from previous activity. I n deciding this point, how-ever, quite recently won facts of no small interest must be takeninto account.It has now been conclusively shown80 that extractsof animal tissues can with equal efficiency take the place of theco-ferment preparations made from yeast itself. I f yeast macera-tion juice is filtered, and the material on the filter thoroughlywashed, the residue, by itself entirely inactive, ferments sugarfreely after the addition of a boiling-water extract of mincedmuscle. The activating substance t.hus deinonstxated in muscle isfound in almost all animal tissues, although absent; from bloodserum.Its chemical properties resemble precisely those associatedwith the co-enzyme of yeast itself, aiid the course of fermentatioiiunder the influence or" a muscle extract is strictly comparable withwhat is observed when the co-enzyme froin yeast is employed.It is stated that the substance, present in both yeast and muscle,which acts as the co-enzyme,of the fermentation acts also as arespiratory catalyst .81 If chopped muscle is thoroughly washed,its power to absorb oxygen may be reduced nearly to zero. It isrestored, bowever, on the addition of boiled aqueous extracts ofeither yeasti or muscle. The oxygen-consuniption of washed yeastis also greatly increased by such extracts, whether their source beyeast itself or muscle. These observat.ions may be held to supportthe old hypothesis that the earlier phases in the processes offermentation and respiration, respectively, are closely related, andsuggest perhaps that, the conversion of sugar into a three-carbonderivative, which can then be fermented (yeast.) or oxidised(muscle), is a process in which the same co-ferment assists.There is no question a t all as to the trustworthiness of thesestatements in so far as they relate to the power of the animal tissueextra& to take the place of the yeast co-ferment in alcoholicfermentation.The experiments are quite easy to repeat, Howfar they ought to modify our attitude towards the view that theco-enzyme of yeast consists of pyruvic acid or acetaldehyde itl isdifficult to decide. Both these substances have been supposed tobe intermediate products in animal metabolism, although proof ofthe supposition is lacking.@: They certainly do notl accumulate t oany appreciable extent in animal tissues, and t-he amounts con-tained in muscle extracts which are effective in stimu1at"ing- ferment-ation must be ipfinitesimal.This circumstance does not, it is true,decide against them as possible activators. We have known fors o 0. Meyerhof, Zeitsch. physiol. Ckem., 1918, 101, 165 ; 102, 1 ; A.,242, 464.81 0. %reY(ll'~lOf, LOC. c i t . s2 8 c c x Avn. Rtport, 1914, 204some time, it should be noted, thaL a hydrogen acceptor, necessaryfor the reduction of mcthylene-blue by muscle, can be washed fromthe tissue by saline solutions, and can then be replaced by acet-aldehyde.It can also, however, be replaced by other s~ibstances.~~The co-enzyme effect may, after all, be due to other reducingagents in muscle. We already lrnow that acetaldehyde, even if thenormal hydrogen acceptor in fermentation, is not specific in thatfunction; other aldehydes are effective. and so perhaps may bebther types of reducing agents,The statements mentioned above with regard to the stimulationof the respiratory process recall others long familiar. The latterwere based on experiments from which it appeared that, tissueswhich have been kept for some hours after death, and in which theoxidative processes are gradually becoming less, can be reactivatedby the addition of aqueous extracts of various fresh tissues.Theseolder experiments have received damaging criticism, but I thinkthe more recent ones, as well as having more precise significance,are based on greatly superior technique, and their results point inan interesting way to the existence of closely related chemicalmechanisms in animal and vegetable cells.Sonrc Tissue Cons tit ?tents.Work at the Rockefeller Institcute seems t c r be satisfactorily clear-ing up the nature and the mode of linking of the amino-sugars inmucins and mucoids. It is thirty years since c". T. MFrnerannounced the presence of chondroitin-sulphuric acid in cartilage.The proof that a conjugated sulphuric acid compound containingan amino-sugar is a constituent of a connective tissue aroused greatinterest a t t5e time, as well it might', but until very recently littleprogress had been made towards a closer characterisation of thistype of tissue constituent.It is now established that two examplesexist : chondroith-sulphuric acid and mucolitin-sulphuric acidrespectively. The former yields chondrosamine (d-lyxohexosamine)oln hydrolysis; the latter, on the other hand, yields mucosin, adisaccharide (C,,H,,O,,N), which breaks down into glucosamine,and glycuronic acid. The chondroitin compound is contained int"he aorta and sclera, t,he mucoitin compound in mucins fromvarious tissues-the vitreous huniour, the cornea, and t'he gastricmucosa, for instance. It. is present also in ovomucoid and inovarian c~st~s.84** A. Harden and H. MacLean, J . PhYS<Ol., 1915, 9, 330.84 P.A . Levene a,nd J. T,bpee-SuRrez, J . B?:oZ. Chew., 1918, 26, 106 ; A . ,i, 564170 ANNUAL HEPORT8 ON THE PROGRESS OF CHEMIS’I’KY.Most satisfactory is it to get definite information as to the rela-tion of the iodine in the thymus gland. From the hydrolytic pro-ducts of the proteins of the gland an iodine derivative of the indole(tryptophan) nucleus can be separated which, as stated in the lastReport’, has a physiological action akin toactivities of the gland itself. Its constitutionbe the following:the physiologicalis now stated86 toPhysiological chemists cannot fail to be interested in the dis-covery of hydrocarbons in the liver of fishes. When this was firstannounced, it seemed likely that such substances might wellbe formed by $he elimination of carbon dioxide from fatty acidsunder the influence of some enzyme of the carboxylase type. I nview of their constitution, this cannot be true. An unsaturatedhydrocarbon, squalene, C&H5”, was first separated 86 from sharkliver oil in 1915, and has now been further studied.87 A saturatedhydrocarbon, CI8Hs, seems, in some specimens of the oil, to beassociated with squalene. Spinacene, first observed in 1915 88 inoils from the livers of species belonging to the Spinacidce, has nowbeen more fully examined, and has been found to have the struc-ture of a terpene.89 We have to think of it, and, maybe, also ofsqualene, for they are probably allied i f not identical, as relatedin metabolism to cholesterol and the bile acids, rather than withfats.There is no doubt that, in the future, comparative studies inphysiological chemistry will throw much light on processes as theyoccur in mammals and on the meaning of many tissue constituents.It is a far cry from the fish-liver hydrocarbons, but I think the samepoint is illustrated by such a fact as that a substhce? helicorubin,found in the (‘bile ’’ of the snail (Helix pomatia), may be looked onas an (‘embryonic ” or (( ancestral” form of haemoglobin. Thissubstance has received fresh attention lately,90 and there can be nodoubt of its close relations with blood pigment. A fascinatingphenomenon discovered in comparative physiology is found in the85 E . C. Kendall, Endocrinology, 1918, 2, 81 ; A., i, 560.86 M. Tsujimoto, J . I n d . Eng. Chem., 1916,8, 889 ; A., 1916, i, 786.87 M. Tsujimoto, ibid., 1917, 9, 1098 ; A., i, 89.* 8 A. C. Chapman, T., 1917, Ill, 56.a9 A. C: Chapmafi, ibid., 1918, 113, 458.90 0. DhM and G. Vegeezi, J . Phyaiol. Path. gin., 1917, 44, 53 ; A., i, 36PHY SlOLOGlC.4 I, CHEM18'l'RY. 171influence of a hormone on the colour of the skin of an animal. Itis said, a t least, that black pigment) cells in the epidermis of Philippine house lizards never, as in ohher cases, expand o r contract,but when these creatures become, for instance, light-coloured onwhite surroundings, the bleaching is due t o the discharge of some-thing into the blood. Adrenaline when artificially injected iscapable of producing the effect, and also bleaches the pigmentin uitro.91 Very interesting, again, are recent studies 93 of theluminescence of various insects and other animals, showing itsdependence on the interaction of two substances, one possibly anoxydase, in the presence of oxygen. I have taken these few refer-ences to ohservatioiis on the lower animals quite at. random.F. GOWLAND HOPIEINS.91 E. G. Ruth and R. B. Gibson, Philippine .7 Sci., 1917, 12, [B], 181.99 E. N. Harvey, Amer. J. Physiol., 1916, 41, 449, 454 ; 42, 318, 342. 349;A., 1917, i, 366

ISSN:0365-6217    

DOI:10.1039/AR9181500143

出版商:RSC    

年代:1918

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AGRICULTURAL CHEMISTRY AND VEGETABLEPHYSIOLOGY.THE distinguishing feature of the year 1918 from the point of viewof the agricultural chemist was the urgent need to increase foodproduction under a growing shortage of f ertilisers and feeding-st'uffs. The problem before him was twofold: to increase suppliesof these essential commodities and to advise farmers how best theymight make use of the limited amounts at their disposal. This isnot the place to discuss the methods adopted or the results; bothare described in the Report on Agricultural Chemistry issued bythe Society of Chemical Industry. Following established custom,this Report deals primarily with advances in our knowledge ofagricultural chemistry rather than with applications of knownprinciples.The Soil.The basis of the farm resources is the soil.Considered in rela-tion to plant growth, it may be regarded as a highly porous masscomposed of solid mineral fragments intimately mixed with decom-posing plant and animal residues. It possesses all the attributes ofcolloids, such as powers of adsorption, retention of water, etc., t oso marked an extent as to suggest that its particles are coated witha gel, which might- well be formed of silica, alumina, iron oxide,and other subst'ances; in contact with all this is the soil moisture,which is presumably saturated with all the soluble substances inthe soil.Allinvestigators agree that iti constitutes the nutrient solution for theplant. In this country it is usually considered t o fluctuate SOmuch in composiLion with rainfall, manuring, and soil treatmentthat it. has proved unattractive to investigators.I n the UnitedStates, however, it is regarded by many as being sufficiently definiteto justify close study, and i t has evoked a considerable bulk ofwork. The soil solut7ion was first. brought into prominence inThis soil moisture is of great importance in crop productionAGRlCULTURAL CHEMISTRY AND VEGETABLE PHPSIOLOGY. 1731903, when Whitney and Cameron published their striking hypo-thesis that it is a saturated solution of the soil minerals in equil-ibrium with them, and therefore of constant composition in allsoils, since all are made up of the same minerals.A series of papers has recently been published from the Cali,f ornian Agricultural Experimental Station which throws consider-able light on the subject. The depression of the freezing point ofthe solution in the soil was determined under varying moisturecondit\ions.This had already been done by Bouyoucos and McCoola t Rgichigaii 1 as a means of expressing variations 111 the concentra-tion of the soil solution, The depressions vary with the moisturecontent of the soil, but. not in a direct ratio; the variation is suchas t.0 suggestt that a certain fractioa of the total water is not sub-ject to freezing, a i d apparently it is so combined that it does notforni ail effective part of the soil solutioii. This assumed fractionis called the “unfree water.” Accepting this method and its con-sequent assumption, the Californian investigator 0, finds that the soilsolution is neither saturated nor constant in composition.ThusWhitney ’s fuiidaniental assumption is controverted. Storageiii a bin greatly increased the soluble matter in the soil; washingwith water reduces it t o a low level, where it remains for a longtime. Cropping the soil also reduces the soluble matter. Allthese propositions are acceptable, and, indeed, were proved bydirect chemical determinations.3 Various soils were set up in largevessels and subjected to definite, but differentl treatments ; somewere cropped and some uncropped. Frequent samples were drawnfor analysis of the water extract, which is supposed t o reflect thecomposition of the soil solution. An enormous amount ofanalytical work was involved, but.it. has long been recognised 4 thatcontinuous curves offer the only safe basis of comparison in soilinvestigations. A great mass of detail is thus obtained whichis difficult to discuss adequately. I n general, however, the graphsare somewhat similar For cropped soils, bnt show striking differ-ences for uncropped soils. The more fertile uncropped sails had ahigher concentration t.han the infertile ones-again in oppositionto the old hypothesis of Whitiiey and in accordance with the resultsobtained a t Rothamsted by Hall, Rrenchley, and Underwood-butin between these extremes there came intermediate soils, in whichthe concentration of the solution was not clearly connected withproductiveness.G . ,I. BOUYOUCO~ and M.M. McCool, Michigan TccJi. BzJE., 24, 1916.D. R. Hoagland, J. Agric. Res., 1918, 12, 369.G. R. Stewart, {bid., 311.4 Compare E. J. Russell and H. B. Hutchinson, J . Agl-ic. Sci., 1909, 3,131174 ANNUAL REPORTS ON THE PROGRESS OF CEEMISTRY.These investigations are further discussed and extended byBurd,5 who sets out the results in terms of. the amounts of solutesextracted by the crop from the soil, and not in terms of concen-tration in the soil. This was done by harvesting portions of thecrop on different dates and determining the soil constituentspresent. Knowing also the amount of water-soluble material inthe soil, he is able to determine how long this supply would lastassuming the daily draft continued a t a constant rate and that thewhole of the soluble material could be taken by the plant.Makingthese assumptions, it is found that there were never less than ninedays’ supply of nitrate or t8wenty-four days’ supply of phosphatein the soil.Now it is distinctly remarkable that even poor soils shouldalways contain sufficient nitrate, phosphate, etc., in the soil solu-tion to supply the plant for a t least nine days, because it isnotorious that additions of nitrates, phosphates, etc., do cause in-creased growth. This, indeed, is the old difficulty urged againstthe original Whitney hypothesis, and the author finds no way out.except the suggestion that in infertile soils the plant is unable toabsorb all the potentially soluble material.When a train of argument leads to difficulties of this sort., it iswell to go back and re-examine the fundamental assumptions; inthis case there are two, namely, that extraction of the soil withwater removes nothing beyond what is soluble in the natural soilmoisture, and that the plant can take the whole of the potentiallysoluble material from the soil.Neither assumption is necessarilysound, and indeed the second is inherently improbable, for soil haspowerful absorbent properties and would be far more likely t ocome into equilibrium with another absorber like a plant-an equil-ibrium, moreover, whieh would only slowly be disturbable-thanto yield up the whole of its supply on demand.Continuing his argument, however, the author proceeds t o addthe quantities of nutrients present in a ‘‘ good crop ” to those foundin the cropped soil, and then compares the result with the amountsfound in uncropped soils. I n the case of nitrates, there is a deficit;this is the usual experience, and implies that the growth of thecrop in some way depresses nitrification. I n the case of phosphates,however, there is an excess; one may suppose that the growth ofthe crop has somehow promoted the solution of otherwise insolublephosphates, etc., or else that the soluble material extracted fromthe uncropped soil does not, represent all that is soluble, but onlythe fraction that is actually dissolved; and, further, that ingood soils the water-soluble material is replaced as fast as the plant6J.S. Burd, J . Agric. Rm., 1918, 12, 297AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY.175absorbs it. I n the case of phosphates, however, the author couldfind no evidence of greater power or rapidity of renewal of solublephosphates in good than in poor soils; in both cases renewal musthave been rapid, because the quantity found in the solution showedno reduction with the growth of the crop.Speaking generally, the results are a t variance with thoseobtained by Whitney and in agreement with those obtained a tRothamsted. The controvertible point still remains whether apoor soil can be said “ t o be able to furnish adequate amounts ofall solutes a t the most critical periods.’’ It may well be that areexamination of the problem, having regard to the phenomena ofsoil adsorption, would lead to interesting results.Turning to the solid phase, this, as already stated, shows markedcolloidal properties, and, indeed, no studies of soil problems cannow be regarded as satisfactory which ignore this fact.A summaryof these properties and a discussion of their bearing on soil problemshave appezred in the form of a monograph.6One of the most remarkable properties shown by the smallestclay particles is that they become flocculated in the presence ofacids and dissolved salts and deflocculated in the presence of alkalis.This phenomenon has generally been regarded as electrical ; claywas supposed to be an electronegative colloid, the charge on whichis neutralisable by electropositive ions. An alternative chemicalhypothesis has, however, been put forward, and flocculationattributed to a combination of clay with the flocculant and thesolute, whereby the aggregation of molecules increases so muchthat they lose the power of Brownian movement and soon settle.’Another important property commonly attributed tpo colloids isabsorption. There is, however, a chemical school that ascribesthis property to the supposed presence of the specially reactiveminerals known as zeolites.It is admitted that no mineralogicalevidence has been obtained of the existence of zeolites in soils, buti t is claimed that the observed phenomena warrant the assumption.If it is conceded that, zeolites occur in the soil and that the absorp-tion and power of exchanging bases shown by zeolites is chemica1,sthen the phenomena of absorption and interchange of bases insoils may be chemical also.This view finds favour among theRussian investigators,D whilst the physical adsorption view is moreP. Ehrenberg, “ Die Bodenkolloide ” (Steinkopf \, 2nd ed., 1918.As claimed by V. Rothmund and G. Kornfeld, Zeitsch. anorg. Chem.,1918, 103, 129; A., ii, 315, in opposition to G. Wiegner’s view that it isphysical, J . Landw., 1912, 60, 197 ; A,, 1912, ii, 981.’ S. U. Pickering, Proc. Roy. Soc., 1918, 94, [A], 315.K. K. Gedroitz, Reprints, A., i. 519 and ii, 364176 ANNUAL 1tEPOItTS ON THE PROGRESS OF CHEMJS‘I‘RI’.commonly accepted in this country, in the United States, and inGermany.Under certain conditions, a precipitate of ferric oxide or othersubstance is formed in the soil at a certain depth below the surface.When this becomes continuous, it.cements the soil particles into alayer of rock 5-7 cm. in thickness, known as a pan, which causesconsiderable damage t o crops by interfering with free movementof water and unduly restricting root growth. The precipitation isnow regarded as a colloidal phenomenon, a change from a soil t o agel. Further observations have been made on the precipitation offerric oxide solutions.1°Yet anot’her property of soil claiiiied as a colloidal phenomenon isacidity. Certain soils turn blue litmus red; it, is assumed, there-fore, that these have the power of preferential adsorption, takingup the basic ions more readily than the acidic, and thereby chang-ing the colour of the indicator. The chemical school, however,stoutly inaintaiiis the presence of substances of acid reaction inthe soil, although with much controversy as tlo whether these aretrue acids or salts of iron aiid aluminium.The believers in trueacids are faced with the difficulty t.hat no undeniable acid has everbeen isolated from the soil except in very minute amounts, butthey have used various methods to demoiistrate their presence-ineasureinent of the hydrogen-ion concentration, rate of inversionof sucrose, liberation of iodine from mixtures of Fotassium iodideand iodate, etc. These all give positive indications, but un-fort-unately in quantitative experiments they do not agree amongthemselves, nor do t,hey show any relationship to the litmus test11or the amouiit8 of lime or calcium bicarbonate required t o“iieutralise ” the soil, t-hat is, to leave an excess of unchangedlime .I2The detemiiiiatioii of the hydrogen-ion coilcentratJon has beenca4rried out mainly in the United States. Remembering how com-plex is the soil solution, m e cannot help asking whether the methodis really applicable and whether investigators are justified inwriting clown definite l’IT values.A4 critical and fundamental in-vestigation into the validity of the method seeins required. In themeantime, measurements are accumulating ; for normal soils thefigures vary from true neutrality to wellmarked true acidity.Manuring the soil with ammoniuiii sulphate or potassium sulphateI ” M. Neidlc, J . Amer.Chem. SOC., 1917, 39, 2334; A., ii, 45.l1 L. J. Gillespie and L. E. Wise, J . Amer. Chew. SOC.. 1918, 40, 796;l2 D. R. Hongland and L. T. Stiavp, J . 2 / g r k . He.?., 1918, 12, 130..I., i, 368AGRlCULTURAL CHEMISTRY AND VEGETABLE PYYSIOLOGY. 177iiicreases the value, the former being more potent than the latter;sodium nitrate slightly reduces it; superphosphate has no effect.18The rate of inversion of sucrose has also been used in the UnitedSt8ates as a measure of the hydrogen-ion concentration, but thismethod involves the assumption that the hydrogen ion is the onlything that can invert sucrose.34 The results do not agree with thoseobtained by the direct electrical or indicator methods; the authorstherefore suppose that these methods simply measure the soluble,but not the total acidity.They consider t>hat an insoluble acidmust operate in the soil, because the amount. of inversion increaseswith the quantity of soil used, which could not be the case if thedissolved portion alone was active. As further evidence of theaction of ail insoluble acid, the authors adduce the fact that“inversion still goes on even in the presence of sufficient lime t omake the solution alkaliue. Again t.he fundamental assumptionis open to question, and it will be askecl whether, in view of thelime result, one can still assunie that inversion is brought aboutoiily by the hydrogen ion. I n these matters, the agriculturalchemist necessarily relies for guidance 011 the physical chemist.It has been shown that the passage of carbon dioxide through asoil increases its acidity, as also does the growth of a crop.Itl issuggested, therefore, that the liberation of the hydrogen ion is dueto carbon dioxide generated within the soil.15Another explanation of’ the pheiioiiieiia of acidity is that it arisesfrom the hydrolysis of salts of iron aiid aluminium formed byaddition of other salts to: the soil. The acidity of certain glacialsoils has been attributed to the “hydrolytic ratio ” between thesalts of ’the alkalilie earth metals on the one hand, and those ofiron and alumiiiium on the other.16Further, it has been argued 17 that the toxic effect. of ‘‘ acid”soils cannot in any case be due t o true acids even if they are pre-sent, because acids added to the nutrient solution in watercultures affect barley and rye similarly, whilst extractsof acid soils affect them differently. Therefore acid soilextracts coiitain something not present in acid nutrient solutions ;on testing, they were found t o contain aluminium.The effect ofalumiiiiuiii salts on plant growth was examined and found t oThe method was intro-duced by L. J. Gillespie, J . Washington Acad. Sci., 1916, 6, 7 ; R., 1916,i, 303.l3 J. K. Plummer, J. Agric. Res., 1918, 12, 19..l4 F. E. Rice and S. Osugi, Soil Sci., 1918, 5, 333 ; A , , i, 620.l5 H. A. Noyes and L. Yoder, ibid., 161.l6 C. H. Spurway, J . Agric. Res., 1917, 11, 659 ; A., i, 162.l7 B. L. Hartwell and F. R. Pember, J. Amev. Xoc. Agron., 1918, 10, 45178 ANNUAL REPORTS ON THE PROGRESS OF CEEMISTRY.resemble t h a t of the acid soil extract.If these observations arewell founded, the conclusions drawn by the authors seem to beirresistible. The hydrogen-ion measurements may indicate thepre2ence of free acid in acid soils, assuming always the validity ofthe method, but the plant test is final; the importance of theseobservations lies in the fact that they make the appeal direct t othe plant.Whatever the cause of soil acidity, it can be remedied by addi-tions of lime. In practice, this is highly important, because acidsoils are infertile for most farm crops, whilst after neutralisationthey may become quite productive.Considerable areas in this country need lime, and cases are notinfrequently recorded 18 where infertile patches in a field are foundto be acid and almost free from carbonates, whilst the rest of thefield, which is still fertile, is not acid and still contains carbonates,although sometimes only little.Besides neutralising soil acidity, lime has other effects less easyt o explain.I t s action on the water-soluble nutrients is foundto differ with the soil and the previous treatment.19 Thus in twosoils the water-soluble potash was increased as a result of liming;in two i t was decreased; in four soils the soluble magnesia contentwas increased ; in one decreased ; sometimes the soluble phosphatewas increased and sometimes it was not’. No explanation is p u tforward of these phenomena, nor is any correlation attempted withother chemical properties of the soils in question.The complex nature of the action of lime may be further gaugedby the difficulty of ascertaining what becomes of it in the soil.Hager clairns’O t h a t only a small part of the added quicklimeappears as carbonate, the remainder being absorbed by soil con-stituents.The power of absorption appears to be related t o theamount of clay present, the process here presumably being physical.but i t is also considered t h a t unsaturated compounds are presentwith which the lime reacts chemically.There are, however, large areas of cultivated land t h a t are acidb u t so far from any source of lime as t o preclude the possi-bility of neutralisation on a large scale. Corville suggested someyears ago21 that a system of “acid agriculture ” might be developedin such cases by means of a suitable rotation of acid-resistantcrops.Inasmuch as a‘leguminous crop would be essential for themaintenance of the nitrogen supply, recent attempts have been18 E. J. Russell, J . Bd. Agric., 1918, 25, 1102.19 A. W. Christ.ie and J. C. Martin, Soil Sci., 1918, 5, 383.2o G. Hager, J . Landw., 1917, 65, 245;: .I., i , 247.11 U.S. Dcpt. of -4p-k. BuU. 6, 1913AGRICULTURAL CHEMISTRY AXD VEGETABLE PHYSIOLOGY. 179made t o study the effect of acidity 01 the nodule organism.= Othersoil bacteria were also included. The soja bean was found to bea suitable crop, growing and fixing nitrogen (through the agencyof the nodule bacteria) even in the presence of soil acidity.Theother bacteria were considerably affected, however. Those grow-ing on gelatin plates were greatly increased in number whensufficient calcium carbonate was added to bring about neutral-isation (using the Veitch method of indicating neutrality), andstill further increases were obtained when phosphates were addedto the neutralised soil. The rates of ammonification and of nitrifi-cation were affected by addition of calcium carbonate before theneutralisation point was reached, and not much afterwards, inwhich respect they differed from the bacterial numbers; non-symbiotic nitrogen fixation was also stimulated, especially in thepresence of phmphate. The general conclusion in regard to non-leguminous plants is that those capable of assimilating ammoniacan flourish in an acid soil, whilst those dependent, entirely onnitrates cannot.The most characteristic soil constituent is the organic matterderived froin residues of plants and animals, and its most significantproperty is that4 it is perpetually undergoing decomposition, withultimate formation of carbon dioxide, water, ’ ammonia, and variousinorganic salts.23 Several agencies are involved, bacteria, moulds,eiizyrnes, etc., and, as the changes go on at low temperature,iiumerous intermediate products are formed .The decompositionis an important factor in soil fertility, because the resulting nitratesare essential to plant$ growth; the process may, indeed, be regardedas the manufacture of plant nutrients in the soil.The original organic substances added to the soil in the plantresidues include carbohydrates such as starch, sugar, cellulose, thepentosans, gums, etc., proteins, nucleoproteins, fats, waxes, andnumerous other substances.The number of possible intermediateproducts is, of course, enormous, and the list of known soil con-stituents is continually being extended; this year, two more coni-pounds have been isolated, benzoic acid and p-hydroxybenzoicacid ; the quantit,y of the latter was distinctly appreciable, amount-ing t o 22 parts per million of soil; there was less than one-tenththis amount, however, of benzoic acid.24 The real importanceof the search for soil constituents will be revealed only when thesa F. E. Bear, Soil Sci., 1917, 4, 433 ; A., i, 206.33 A detailed comparison has been made of the inorganic oomposition ofSee C.F. the original plant and that of the pea6 to which it has given rise.Miller, J. Sgric. Res., 1918, 13, 606.24 E. H. Walters, J . Amr. Chem. SOC., 1917, 39, 1778; A., i, 1612180 ANX'UAL REPOR'I'S ON THE PROGRESS OF CHEMISTRY.process of formation and the functions of the compounds areunderstood.The main interest a t present lies in the mechanism of the procesg,for until this is known it is difficult to interpret the chemical data.Chemical and biological invest-igations should go on side byside, but for the time being the biologists have outstrippedthe chemists. In view of the general similarity both ofthe initial products and of the conditions o€ decomposition indifferent soils, it is reasonable t o anticipate similar intermediateproducts.In last year's Report some evidence was adduced onthis important fundamental point ; the nitrogen compounds revealedby the Van Slyke method were said to be much the samein all soils examin+i.25 It has since been shown, how-ever, that this method does iiot, apply to soils, being vitiated bythe ferric salts formed from the soil during the hydrolysis. Thisis an unfortunate setback, but it illustrates the great! difficultiesunder which the soil investigator labours. Progress is largelydependent on the introduction of new methods and conceptionsfrom pure chemistry, but a t every stage the closest scrutiny isnecessary to ensure that the proposed method is really valid.Broadly speaking, investigations proceed in two directions : theactual processes in the soil are as far as possible traced out, andinformation is accumulated as to the way in which given kypes ofcompounds decompose in tho soil.Aliphatic nitrogen compounds are more easily converted intoammonia than aromatic aniino-compounds, and these in turn morerapidly than aromatic iniino-compounds .26 Thus the compoundstested broke down to ammonia in the following order: acetamidemost readily, then leucine, tyrosine, benzamide, acetanilide, andfinally benzanilide.Another investigator 27 has shown that di-cyanodiarnide does not decompose in the soil, whilst cyanamiderapidly breaks down, a fact? which may throw some light on itsconstitution.The efforts to trace out the actual processes in the soil have metwith considerable success.Two general types of change areknown: a degradation, whereby protein breaks down to formammonia: and a remarkable constructive change, in which gaseousnitrogen is converted into protein. About the steps i n thissynthesis nothing is known, but the conditions under which it takesplace have been examined in the Rothamsted laboratory.% Az6 Ann. Report, 1917, 203.28 K. Miyake, J . Amer. Chenz. SOC., 1917,39, 2378 ; A., i, 91.27 G. A. Cowie, J. Agric. Sci., 1918, 9, 113.28 R. B. Hutchinson, J . Agri'c. Sci., 1918, 9, 92source of energy is obviously necessary; this is supplied by thedecomposable carbohydrates. When plant residues were added tothe soil, fixation of gaseous nitrogen was observed amounting to9 milligrams per gram of substance added.Other necessary condi-tions are suitable temperature, presence of phosphates and ofcalcium (or magnesium) carbonate. This process is wholly beneficial.In addition, another synthetical process was observed starting fromnitrates; this is harmful, because it. results in t-he temporary with-drawal of nit'rate from the supply available for the plant. Inpractice, therefore, the carbohydrate or plantl material would beadded in autmnn? when the temporary withdrawal of nitrate doesnot seriously affect farm crops and the fixation process has time totake place before spring. The organisms concerned, A zotobacter,are widely distributed.2gThe decomposition of sulphur compounds with final productionof sulphates has received some attention in tihe United States,especially the relations of '' sulphofication " t o other soil decomposi-tions.30It will surprise no organic chemist that during the degradationof organic compounds in the soil there is a considerable productionof a black, non-crystalline material soluble in sodium hydroxide andlargely precipitated by acids.Formerly, this so-called humus wassupposed t.0 be an intermediate product in the production ofnitrates, and therefore it was estimated so as to give a measure ofthe potential fertility of the ~0il.31 Several investigators of recentyears have shown tmhat it is not related to fertility, but is, as mightbe expected, a by-product rather than a.main product. Furtherevidence: is now offered from the soils in orange groves.32The decomposition is brought about by bacteria, fungi, and otherorganisms, but their relative part is. unknown. Indeed, theevidence in favour of activity of fungi is by no means unexception-able. It has been argued, for instance, that fungi must operatein the soil, because approximately equal amounts of carbon dioxideare evolved from sterilised soil whether moulds or bacteria are29 P. L. Gainey, J . Agric. Res., 1918, 14, 265, found them in 59 per cent.of the soils examined ; in these cases the PH value was less than 6.ao Of papers published this year the following may be mentioned : J. W.Ames and T. E. Richmond, Soil Sci., 1918, 5, 311. H. C. McLean, ibid.,251 : this deals especially with the oxidation of sulphur by micro-organisms.0. M.Shedd, J . Agric. Res., 1917,11, 91 ; A., i, 96 : the effect of sulphur oncrops and soils.31 New methods of estimation are still devised by ingenious chemists,although the value of the results is no longer generally admitted. See, forexample, A. Jakobsen, Zhw. Qpt9n. Agron., 1916, 17, 93 ; A., ii, 136.32 C. A. Jensen, J . Agric Res., 1918,12, 505182 ANNUAL REPORTS ON THE PlCOQRESS OF CHEMlSTH1’.intxoduced.33 The argument; is not really valid, because heat-ing soil is well known t o make it suitable to certain types ofmoulds.A new method of counting soil protozoa has been devised, makinguse of the apparatus for counting blood corpuscles; there are nowfive methods available.34The important part played by bacteria in the decomposition ofthe organic matter of the soil and the vital importance of the pro-ducts as plant nutrients have led t o careful study of khe relation-ships between soil conditions and bacterial activity.In general,these are the same as the relationships between soil conditionsand plant growth, plants and bacteria both being livingthings and affected similarly by the same biological factors.This similarity has been well brought outl in an investigationon the effect of sodium nitrate on the nitrogen transform-ations in soils.35 Sodium nitrate increased the numbers of ’ammonifying bacteria, and in normal soils increased also theamount of decomposition of added protein; in alkali soils, how-ever, there was apparently some rearrangement of the flora, so thatthe simplified material was assimilated, thereby masking the decom-position effect. Fungi were even more affected than bacteria.Thenitrifying and nitrogen-fixing organisms both benefited up to acertain point, beyond which further increases in the amount ofsodium nitrate cause a falling off in activity. A more detailedstudy of the effect on the nitrogen-fixing Azotobacter has beenmade.36 Small quant,ities of the nitrates of potassium, sodium, orcalcium caused great increases in the numbers of Azotobacter insterilised soil, although not’ a commensurate increase in the amountof nitrogen fixed. The nodule organism, BaciZZzcs radicicola, alsoincreased in numbers after addition of nitrates, butl the gain infixed nitrogen was only slight and there was an actual depression ofnodule formation which could not easily be explained.Moreover, it is shown37 that in alkali soils the excess of salinematter impairs the vitality of the organisms; after the excess ofsalts is washed out, however, the organisms act more vigorously.The ammonifying organisms are the most hardy, next come thenitrifying organisms ; both these tolerate more salinity than culti-vated plants, so that in the washing-out’ process the activity of thenitrate-forming organisms becomes marked before the soil is yet33 R.S. Potter and R. 5. Snyder, Soil Sci., 1918, 5, 359.A. Itano and G. B. Ray, ibid., 303.D. A. Coleman, {bid., 1917, 4, 345.3@ T.L. Hills, J . Agric. Rea., 1918, 12, 183; A,, i, 328.37 J. H. Barnes and B. Ali, Ag&. J . India, 1917, 12, 388; A., i, 182ready for plant growth. These observations are of great interestin connexion with the reclamation of alkali land.The effect of calcium and of magnesium carbonates on the soilbacteria has been studied in some detail.% Both carbonatesincrease the numbers of Azotobacter and also of bacteria growingon gelatin plates, especially in acid soils; magnesium carbonate ismore potent than calcium carbonate. The effect is in the main aneutralisation of acidity,. butl it is something more, because itincreased by further additions after the neutralisation point isreached.It has frequently been assumed that bacteriotoxins must existin the soil, since they are known to be formed in certain culturemedia.The question has been examined very thoroughly,but all the supposed proofs are shown to be faulty.39 The essentialdifference between an artificial medium and a soil is that in theformer the bacterial flora is pure, or ata any rate limited in variety,whilst in the soil itl is exceedingly complex, many of the organismsdepending on the products of activity of others. Not only couldno experimental evidence of the existence of bacteriotoxins beobtained, but it was further shown that the assumption of toxinsleads to difficulties. Thus, it is necessary to suppose that heatingfresh soil for fifteen minutes is sufficient, t o produce toxins but notto destroy them, whilst heating for sixty minutes both producesand destroys them, and in the case of air-dried soils fifteen minutes'heat causes their decomposition.Aeration and water supply of the soil arc3 highly importantfactors in its relation t o plant growth.Aeration has receivedparticular attention in India under Howard and his co-workers.The effect of adding potsherds or sand to the Pusa soil is shownto increase nitrification40 and plant growt*h; in the case of Javaindigo, the increase was as much as 40 per cent. The effect is nodoubt complex, but evidence is adduced t o show that excess ofcarbon dioxide in ~ soil air adversely affects plant development.Some highly important practical consequences follow. Floodirrigation on fine alluvial soils interferes with their ventilation byrapidly destroying the texture and forming a compact surface crustimpermeable to air.One limiting factor, water, is removed, butanother, the need of aeration, is introduced. Thus over-irrigation** H. L. Fulmer, J . Agric. Res., 1918, 12, 463; see also F. E. Bear, SoilSci., 1917, 4, 433.30 H. B. Hutchineon and A. C. Thaysen, J. Agrzc. Sci., 1918,9, 43.40 A. Howard and Rb S. Hole, Indian Science Congress, Lahore, 1918.Indian Forester, 1918, 187 : 3. N. Sen, J . Agrk. Scd., 1918, 9, 32. For theeffect of oxygen and carbon dioxiae on nitrification and ammonification,see J. K. Plummer, CorneU U n h Agr. Expt. Stat., 1916, Bull. 384 ; A,, i, 90184 ANNUAL REPORTS ON THE PROGRESS OF CHEMWl'RT.actually diminishes the yield. 'rhis is further shown by resulbobtained at Quetta, where 13 rnaunds of wheat were obtainedwith one irrigation and only 8 maunds where three irrigationswere given.In any flood irrigation system, therefore, a practicalcompromise between the needs of the plant for air and for watermust be worked out. This has been accomplished at? Quetta bythe proper utilisation of the preliminary watering given before sow-ing. Under t.his new system, the yields obtained are often higherthhan with the six or seven waterings usually applied. The Quettaresults have been shown by experiment t o apply to the Punjab andSind, where about half the irrigation water now used could besaved. The economic significance of these results becomes apparentwhen it is remembered that the annual revenue derived fromirrigation works in India is &5,000,000 sterling.It is further shown that aeration probably influences tahe dis-tribution of plants, and is therefore of importance in ecological 40lLstudies.Finally, a new method of pot culture is described which allowsclose study of root development .41The power of retaining water is intimately bound up with thesize of the soil particles as revealed by mechanical analysis, and isespecially marked in the case of the smaller particles. Thus, the'' moisture equivalents " 42 of the separate fract,ims of a soil wereas follows : 4sCoarse fractions, down to and including the fineVery fine sand (0.10 to 0.05 m.in diameter) ...Silt (0.05 t o 0.005 mm. in diameter) ...... 25Clay (below 0.005 mm. in diameter) ... ... 61sand 0.10 nun. in diameter ... ... ... 1-24.6The equivalent for the whole soil, however, is not the sum ofthe equivalents of the separate fractions, although it is notl greatlydifferent, but soils of the same mechanical analyses did not havethe same equivalentls. Methods of calculating equivalents are basedon the assumption that the property is additive, and therefore notwholly trustworthy. The moisture equivalent is affected by salts,especially after they have been washed out; it, is assumed that'On For the benefit of chemists who are out of touch with modern botany itmay be said that ecology deals with the relationships between t,heplant and its environment.I1 A. Howard and G. L. C.Howard, Agric. J. India, 1918, 36.*? For methods of determination, see F. J. Alway, M. A. Kline, and G. R.McDole, J . Agric. Rea., 1917,11, 147 ; A., ii, 47.A . Smith, Soil Sci., 1917, 4, 471AGRLCLJLTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 185this results from changes in the degree of dispersion of the soilparticles, and the consequent alteration in the interfacial surface."The relationship of physical textlure of soil to crop production inIndia has also been discussed.45Fertilz'scrs.\Vork 011 fertilisers has been confined in the main to methodsof increasing supplies, on which serious inroads were made by theRiIinist'ry of Munitions. The problems were of considerabletechnical interest, butq no new scientific principle was brought out ;ail account is given in the Report to the Society of ChemicalIndustzy, and need not be repeated here.Perhaps the most important scientific work was on cyanamide.For long it has been known that this substance under certain con-ditions changes to dicyanodiamide ; 46 the agricultnral interest int.he change lies in the fact that dicyanodiamide is toxic to plants,whilst cyanamide is a valuable fertiliser.It is now shown47 thatdicyanodiamide is also toxic t o the nitrifying organisms, but it dbesnot stop ammonia production; in admixture with cyanamide itscarcely impeded the production of ammonia, but completely pre-vented the further changes t o nitrate. There are considerabledifferences between ammonia and nitrate as plant nutrients, theformer being, on the whole, less efficient than the latter.Noevidence could be adduced that clicyanodiamide breaks down inthe soil, although cyanamide easily deconiposes ; whatever thereaction may be. it clearly cannot3 involve the formation ofdicyanodiamide .Yla.nd Growth .The most fundamental process in plant gruwt'h is the assimila-tion of carbon dioxide and its transformation into sugar. Thephysical processes were elucidated in 1900 by H. T. Brown andF. Escombe in 'a classical series of investigations, which was againpresented with great advantage to the younger chemists by Dr.Brown in his lecture before the Chemical Society in May.# The4p 3;. T. Sharp and D. D. Waynick, Soil Sci., 1917, 4.45 D. Clouston and A. R. P. Aiyer, Agric. J. India, 1918, 89.46 A paper on the constitution of dicyanodiamide deserves mentionW.J. Hale and F. C. Vibrans, J. Amer. Chem. Soc., 1918, 40, 1046 ; A.,i, 380. The authors favour the cyanoguanidine structure, NH;C( :NH).NH.CN,suggested by Bamberger in 1880.47 G. A. Cowie, J . Agric. Sci., 1918, 9, 113 : confirmed also by L. Moller,Biochwn. Zeitwh., 1918,.88, 85 ; il., i, 469. 4 5 T.. 1918,113. 569186 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.chemical processes are not clearly worked out. Baeyer’s well-known hypothesis that formaldehyde is the first product has metwith considerable criticism, but has recently been strongly sup-ported in Germany. It is pointed out49 that of all possibleprimary products, formaldehyde is the only one in the formationof which the volume of carbon dioxide absorbed is equal to thatof the oxygen liberated.The so-called (‘ assimilatory quotient ”CO,/O,, which is therefore 1 in the case of formaldehyde, is 1.33for glycollic acid, 2 for formic acid, and 4 for oxalic acid. Nowprecise determinations show that the quotient is exactly 1 whetherthe temperature is loo or 3 5 O , whether the atmosphere is rich incarbon dioxide or even free of oxygen altogether, and whetherordinary foliage or xerophytic leaves like cactus are examined.I n spite of this kind of negative evidence many chemists remainunconvinced, an important difficulty being that carbon dioxidecannot by any known process be reduced to formaldehyde, and evenits reduction to formic acid is only brought about by powerfulagents which in no wise reproduce the conditions in the plant.Tosome extent the difficulty is diminished by the discovery50 of anew reaction whereby the reduction of carbonic acid to formic acidoccurs with the intervention only of hydrogen peroxide, which isknown to occur regularly in plant,s. When a saturated solution ofpotassium hydrogen carbonate reacts with a 10 per cent. solutionof hydrogen peroxide, the following change takes place :H,02 + E[$CO] = H20 + 0, + H*CO,K.So far as it goes this is helpful, but there still remains the furtherreduction to formaldehyde, which, the author admits, is altogethera more difficult step.The formaldehyde is then supposed to change to sugar, which istemporarily stored as starch, but sooner or later passes from theleaf to the sto,rage organ, whether grain, stems, root, or tuber, inwhich it is stored in some characteristic manner.Some plants,such as Jerusalem artichoke, dahlia, and chicory, store thecarbohydrates as inulin in their roots. Direct experiment withthese has shown 51 that the inulin is certainly not found in theleaf or translocated as such; it, occurs only in the undergroundorgan, being formed from sugars tramslocated from the leaf.( 9 R. Willstlitter and A. Stoll, Ber., 1917, 50, 1777 ; A., i, 207. For amethod of measuring photosynthesis see W. J. V. Osterhout, Amer. J . Bot.,1918, 5, 106, and Science, 1918, 47, 420; A., i, 471.50 H. Wislicenus, Ber., 1918, 51, 942; A., i, 473.51 H. Colin, Cornpt.rend., 1918,166, 224 ; A., i, 161AQRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 187During the period of rest, however (that is, during the wintermonths), the inulin becomes gradually converted into sucrose andl;evulosans.52An investigation has been made of the carbohydrates of mul-berry leaves which, apart from its physiological interest, has apractical hearing in that it deals with the food uf the silkworm.53The nitrogen required by the plant is taken up in the form ofnitrate, but it obviously has to undergo important changes beforeit appears in the final form of protein; in particular, there mustbe a reduction either of the nitrate or of a nitro-compound. Ithas been shown54 that ferrous sulphate and sodium carbonate reactwith aldoses, ketoses, catechol, quinol, quercetin (representingyellow plant pigments), chrysarobin (representing the anthranols),.and other plant constituents to foim a complex compound whichin the presence of oxygen can carry out, either reduction, convert-ing nitrites to nitric oxide and ammonia, or nitrobenzene to aniline.Further, all these compounds are autoxidisable ; they take upoxygen, and in presence of water produce hydrogen peroxide.The iron exists as an l C internal complex ” and does not show theordinary reactions; only traces are needed, but its presence isessential; neither manganese nor copper has the same effect.It is particularly interesting that these widely distributed organicsubstances should have the power of, bringing about oxidations onthe one hand, and, in the presence of iron, reductions on the other,and that both reactions should take place in the presence of oxygen.Numerous investigations have been made of other organic con-stituents of plants.One by Everest, on the production of antho-cyanins and anthocyanidins55 in plants, is of interest because forthe first, time it shows the presence in the same flower of an antho-cyanin pigment and of the flavonol derivatives from which it wouldbe formed by reduction. The anthocyanin pigment of the purplish-black viola ‘( Black Knight ” is shown t o be a delphinidin glucosideidentical with the violanin obtained by R. Willstatter and F. J.Wei1.56 The yellow sap pigment from the same pansy contains amyricetin glucoside and another yellow sap pigment which doesnot give a green coloration with dilute alkalis.The pigment of myrtle berries has been examined, and is saidt o be identical with oenocyanin, the colouring matter of wine.5762 H.Colin, Compt Tend., 1918,166, 305 ; A., i, 208.K8 S. Kawase, J . Tokyo Chem. SOC., 1918, 39, 245 ; A., i, 476.64 0. Baudisch, Ber., 1918, 51, 793 ; A., i, 474.A. E. Eveiest, Proc. Roy. Soc., 1918, [B], 90, 251 ; A., i, 420.6% R. Willstiitter, and F. J . Weil, Annalen, 1916, 412, 178 ; A., 1917, i, 46.C. Marini, Annali Chim. Appl., 1918, 10, 32 ; A., i, 519188 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The occurreuce of carotin in various seeds has been recorded; itwas found in the seed of flax, mustard, and black sesame, but notin the seed of rape, white sunflower, turnip, safflower, or cotton.68Great possibilities are suggested by a research started inAmerica 59 to discover the substances in the cotton plant whichprove so attractive t o the boll weevil.This insect causes disastrouslosses, and there is no certain means of control. If the attractivesubstance could be discovered it! might? be used for baiting traps,aiid if, better still, it could be bred out of the plant, much mightbe acconiplished.The phytosterols of wheat have received soille attention; it isshown 60 that sitosterol is the chief representative of this group inthe wheat grain, although another occurs in the bran. Thequantity present in the young plants is greater than that in t9heoriginal grain so long as growth is normal, but in etiolated plantsthere is a falling off. It is suggested thatl those sterols form anessential part of the cell membrane. Representatives of the groupare also found 61 in the lower plants-funqi, seaweed, sphagnum,agaricus, etc.Of the nitrogen compounds in plants, the legumiii in peas hasbeen shown to coiisist of a t least two distinct substances, one solubleand the other insoluble in dilute salt' solution, but the latter isextractable by water O;L' dilute alkali and can be precipitated withdilute acetic acid.G2The protein of the Chinese velvet, bean has been shown to consistmainly of a new globulin, t o which the name stizolobin is given; 63examinations have also been made of the globulin of buckwheat@and the stachydrin of lucerne.65An improved method has been devised66 for extracting nucleicacid from yeast and from wheat embryos; the purified productswere found to contain nitrogen and phosphorus in t'he proportionsrequired by Levene's 67 formula, C,,H,,O,,N,,P,.The complex carbohydrates, cellulose.pectins, f urfuroids, etc.,A. H. Gill, J . I n d . Eng. Chem., 1918, 10, 612 ; d., i, 476.345 : see also E. E. Stanford and A. Viehoever, ibid., 419.59 A. Viehoever, L. H. Chernoff, and C. 0. Johns, J . Ag&. Res., 1918,13,6o M. T. Ellis, Biochem. J., 1918, 12, 160: A., i, 420.Ihid., 12, 173; A., i, 420.0. Hammarsten, Zeitsch. physiol. Chew., 1918, 102, 86 ; A, i, 509.63 C. 0. Johns and A. J. Finks, J . BioZ. Chent., 1918, 34, 429 ; A., i, 316.64 C. 0.Johns and L. H. Chernoff, ibid., 439; A., i, 318.86 H. Steenbock, ibid., 1918, 35, 1 ; A., i, 476.66 G. Clarke and S. B. Schryver, Biochem. J., 1917,11, 319 ; A., i, 130.P. A . Levme, Riochem. Zpitsrli., 1909, 17, 120 ; A . , 1909, i, 541form a large part of the plant tissue, but their chemical charachr-isation is still very incomplete, and no great additions to our know-ledge can be recorded this year.Recent investigation has brought out the fact that cellulose isnot hydrolysed t o dextrose, as was formerly supposed, but' to morecomplex esters of polysaccharides which contain acidic hydroxylgroups.68 The constitution suggested for cellulose, which supposesi t to be a polydextrose anhydride, is therefore without experi-mental support.More definite evidence has been puti forward ofthe occurrence of methyl pentosans in cereals and the soya bean,G9on which doubts have been castl, and it. has again been emphasisedthat other substances besides pentoses and pentosans yield f urfur-aldehyde under the conventioiial method of distillation with hydro-chIoric acid.70Investigation of the pectins, t.he basis of fruit jellies, has broughtout little more than the facts that methyl alcohol can be split off,and that various preparations yield furf uraldehyde correspondingwith between 35 and 46 per cent. of arabinose and 6 and 10 percent. of methyl peiitose.71The chief phosphorus compounds of wheat and other cerealgrains are ort.hophosphoric acid and inositolpentapliosphoric acid,C6H6(OH)(H2P04)5.72Many attemph have been made to ascertain the functions of thenumerous organic substances found in plants, or, less ambitiously,to discover whether they are harmful or beneficial to the plant.Many are harmful, especially i n water culture, but? in a t ldast onecase73 the plant is immune to the toxic principle it" itself produces;A qrostemma.g i t h n p is not affected by its glucoside agrostemina-saponin even in 1 per cent. solution, whilst peas, radishes, and buck-wheat are markedly injured by as lit8tle as 0.01 per cent. Othercompounds are somewhat. specific in t-heir eff ects. Mandelonitrilealmost prevents germination, but is not poisonous afterwards,although when given to seedlings it so alters the habit, of growthas to give the appearance of a new species; strychnine, morphine,and caffeine, on the other hand, do not prevent germination, butare toxic afterwards.Some of the results suggestl that, the glkaloids may have a definite69 K.Oshime and K. Kondii, J. Tokyo Chern. SOC., 1918, 39, 185, 294;'O R. Gillet, BuZE. Assoc. Chirn. Suer., 1917, 35, 53 ; A., ii, 248.'l T. von Fellenberg, Biociiem. Zeitsch., 1918, 85, 118 ; A., i, 216.J. B. Rather, J. Amer. C&em. SOC., 1918,40, 523 ; A., i, 212.7y R. Combes, Compt. rend., 1918, 167, 275.M. Cunningham, T., 1918,113, 173.A., i, 419 ; ii, 338190 ANNIJAI, REPORTS ON THE PROGRESS OF CHEMISTRY.function in plants,74 perhaps that of hormones. Just as in animalsthe adrenaline of the suprarenal glands is produced from tyrmine,so in plants the waste products, originally indifferent, may be trans-formed to something serviceable.The curious observation is recorded that galactose and mannoseeven in dilute solutions are very toxic to the roots of peas andwheat, although dextrose and sucrose were able to actl as anti-dotes.75 Hydrocyanic acid is likewise extremely toxic, 1 partl in100,000 of the culture solution being sufficient to kill immediately;sodium cyanide proved equally toxic.Neither compound showedany sign of a stimulating effect in any d i l u t < i ~ n . ~ ~Results obtained in water culture are of considerable physio-logical interest, but they do not necessarily show what! happens inthe soil, for it is well hown that considerable biochemical trans-formations take place in soil, and organic compounds toxic inwater may be decomposed quickly.Thus vanillin, whilst immedi-ately harmful as in water culture, soon disappears77 and leaves noaft er-e ff ects .The inorganic plantl nutrients figure much more prominently inagricultural chemistry than the organic constituents of the plant,because they are more under control. The process by which theyare absorbed is commonly considered to lie outside the purview ofthe agricultural chemist, but is of never-failing interest t o thephysiologist, and there is a constant flow of papers on its variousaspects. Osterhout and his school regard the process as physical;Stiles And Jgrgensen consider i t to be chemical.78One of the most remarkable of the phenomena connected witht,he inorganic plant$ nutrients is the injury caused to the plant whensingle substances, and not mixtures of substances, are presented tothe roots, or when one subst.ance greatly preponderates over others.A full investigation was made by Tottingham79 four years ago;eighty-four different mixtures of four salts were used for plantgrowth; all had the same total concentration, but the proportionsof the four ingredients varied ; some of the solutions caused specificinjury to wheat seedlings, whilst others produced excellent growth74 G.Ciamicipn and C. Ravenha, Gazetta, 1917, 47, ii, 109 ; Atti R. Accad.76 L. Knudsen, Arner. J . Bot., 1917, 4, 430 ; A., i, 95.76 Miss W. E. Brenchley, Ann. Bot., 1917,31, 447 ; A., i, 95.77 M.J. Funchess, Alabama Agric. Expt. Stat. Bull. 191, 1916 ; A., i, 150.78 W. J. V Osterhout, Bot. Gaz., 1917,63, 77, 317 ; A., i, 472. S . C. Brooks,ibid., 1917,64, 230, 306 ; A., i, 472 ; W. Stiles and I. Jargensen, Ann. Bot.,1917, 31, 415 ; A., i, 94 ; Bot. Gaz., 1918, 65, 526 ; W. Stiles aind F. Kidd,PTOC. Roy. Soc., 1918,11.Lincei, 1918, [v], 27, i, 38 ; A., i, 93, 473.70 Physiol. Remarch, 1914, 1, 133and had no toxic effects. These observations have been consider-ably extended. Magnesium 80 and phosphoric acid in certain pro-portions both tend to produce injury, especially when the totalconcentration exceeds a certain point. Monocalcium phosphate inits toxic doses was more harmful than potassium phosphate, butthe effects were quite definite.81 Ammonium sulphate also causesinjury when given alone or in preponderating quantity in a mix-ture.Where increased yields are obtained they are due, not toadditional nitrogen, but to a redressing of a disturbed balance.82Indeed, the American physiologists consider that the cation of anysingle salt is toxic, but its toxicity is overcome in a properlybalanced mixture of t-wo or more salts. The French investigatorsclaim an exception in calciumf3 a t any rate in its effects on seedlinggrowth; for in the presence of a calcium salt seedling growth ismuch more rapid than in pure water, but this effect is decreasedand not heightened by the addition of other salts. Thus thedifferent metals, whether toxic or nutritive, are antagonistic tocalcium in seedling growth, just as calcium is anti-toxic towardsthem.A close relationship is claimed 84 between antagonism andeffects on permeability, all solutions which permit normal growthpreserving normal permeability.Investigation continues of the effect of other inorganic elementsbesides the classical three (nitrogen, phosphorus, and potassium) ;J. A. Voelcker in the Hills's experiments has examined magnesiumsalts; American investigators have found lithium in all plantsexamined, rubidium in most, and msium in a few,85 whilst it isalso shownsG that aluminium occurs only in small quantities inxerophytes, but in much larger amounts i n other plants. Theeffect of boron compounds on plant growth has been examined.87There is little to, record in the investigation of crop composition;quality of crop, once of interest to the agricultural chemist, hasreceded to the background in a hungry world clamouring only forquantity.One paper has appeared on the old problem of theFor injurious effect of magnesium carbonate in water cultures, see H.Coupin, Compt. r e d . , 1918, 166, 1006; for soil experiments, see J. A.Voelcker, J . Roy. Agric. Soc., 1916, 77, 244.81 J. W. Shive, Soil Sci., 1918, 5, 87.85 L. Maquenne and E. Demoussy, Compt. rend., 1918, 166, 89 ; A., i, 149.84 W. J. V. Osterhout, Science, 1917,445, 97 ; A., i, 471 : see also L. W. H.van Oyen, Biochern. Zeitacch., 1918, 87, 418; A., i, 472, who attempts tocorrelate the physical properties of the salts with their biological action.ys W.0. Robinson, L. A. Steinkoenig, and C. F. Miller, U.S. Dept. Agr.,Bull., 1917, No. 600; A., i, 331.86 J. Stoklasa and others, Biochern. Zsitsch., 1918, 88, 292 ; A., i, 475.87 F. C. Cook and J. B. Wilson, J . Agric. Res., 1918,13, 461.82 M. I. Wolkoff, ibid., 123192 zSNNUAI, ItEl’OR1’S OX ’J’HE -PROGRESS OF CHEMISTRY.strength of whe&t,BB the main point of which is that the gluteuof weak flour is a different chemical unit from the gluten of strongflour, coming nearer the boundary which separates the crystalloidfrom the colloid state.The probleins of grain st’orage have received attention,*Q and incrop growth more data have accumulated on t.he comparative ratesof transpiration of maize and sorghum 00 and on the relationshipof the density of cell sap t o the ability of plants to siirrive lowtemperature.01The chief concern of agricultural chemists in t.his country hasbeen to show how the limited supplies of feeding stuffs might beused to the best advantage, but in countries affected by the blockadethere has been a vigorous search for substitutes for which muchsuccess was claimed.The best is said t o have been straw digestedwith dilute sodium hydroxide solution, but. a number of others-leaves, heather meal, etc.-have been used; they are described inthe Report- to the Society of Chemical Industry.Of scientific work, perhaps the most interesting comes from StateCollege, Pennsylvania. The low return for the last pound of foodin fattening is traced to the increased inaiiitenance requirementl ofthe fat as compared with the lean ox; it is not due, as hascommonly been supposed, to the falling off in efficiency of utilisa-tion of the nett energy.92 Dr.Armsby has summarised his re-searches in a new volume, “The Nutrition of Farm Animals,”which will be welcomed by agricultural chemists. It may be notedthat he attaches less importance than usual to starch equivalents,which, he considers, may obscure the energy relationships.Several digestibility studies have been completed. The powerof digesting starch is shown to increase rapidly in the young calfbetween the fourth day and the third week after birth.93 I n olderanimals, the digestion coefficients are said to be reduced when foodsare given together instead of singly.94The efficiency of various proteins for purposes of milk produc-tion has been determined, the protein of distillers’ grains beingR.A. Gortner and E. H. Doherty, J . Agvk. Rea., 1918, 13, 389.89 C. H. Bailey and A. M. Gurjar, ibid., 1918,12, 685.S. C. Salmon and F. L. Fleming, ibid., 1918, 13, 497.g1 E. C. Miller and W. B. Coffmmn, ibid., 1918, 13, 679.na H. P. Armsby and J. A. Fries, ibid., 1917, 11, 451 ; 1918, 13, 43.ga R. H. Shrtw, T. E. Woodward, and R. P. Norton, ibid., 1918,12, 575.94 P. V. Ewing and F. H. Smith, ibid., 1918, 13, 611more effective than that of gluten feed. which again is I ~ O T Beffective than that of cotton ~eed.9~The composition of milk has received some attention. The verycomplex mixture of glycerides forming the fat has been againexamined,g0 and a new method of esterificatioii suggested, basedon the use of hydrochloric acid as ~atalyst.9~A new protein has heell rouiid in milk resembling the gliadin ofwheat in its solubility in 60-80 per cent.alcohol; several pre-vioiisly described proteins have been more definitely characterisecl .QHThe method of preparation of pure caseinogen from milk hasbeen considerably irnproved.99A method for isolating citric acid from inilk is described,’ andthe mechanism of the souring process discussed.2Further data have been published on the old question as to therelationship betlweeii yield of milk and percentage of fatq. A nega-tive correlation was found; where the yieId was high the fat waslow, and vice versa.3Fermentation.Slator has continued his investigations on the phenomena ofkhe growth of yeast, and shows that it involves three stages: alag-phase or period of quiescence, during which there is no growth;a period of unrestricted growth, when the rate follows a logarithmiclaw ; and a period of retardation, due to the accumulation of carbondioxide or deficiency of oxygen.4An important experimental confirmation has been obtained oft.he hypothesis that acetaldehyde is an intermediate product in theformation of alcohol by ferment.ation. Action can be stopped a tthis stage if the prolcess is carried out in presence of sodiumsulphite ; the acetaldehyde then accumulates in the form of the95 E.B. Hart and G. C.Humphrey, J . Biol. Chem., 1918, 35, 367 ; A.,96 C. Amberger, Zeitsch. Nahr. Genussm., 1918, 35, 313 ; A., i, 418.97 E. B. Rollsnd and J. P. Buckley, j m . , J . Agric. Res., 1918, 12, 719;9B T. B. Osborne and A. J. Wakeman, J. Bio2. Chem., 1918, 33, 7 ; A.,gg L L. Vaa Slyke and J. C. Baker, ibid., 35, 127 ; A., i 413.i, 465.- I . , ii, 250.i, 141.H. H. Sommer and E. B. Hart, ibid., 313 ; A., i, 465.L. L. Van Slyke and J. C. Baker, {bid., 147 ; A., i, 417.E. Roberts, .7. Agric. Rea., 1918, 14, 67.A. Slator, Biochem J , 1918, 12, 248 ; A., i, 564.HEP.-VOL. X V . 194 ANNUAL &ttEPOltTS ON THE PROGRESS OF CHEBIISTKP.bisulphite compound, no less than 73.5 per cent. of the theoreticalquantity being obtained. Further, it is shown that acetaldehydeis readily reduced to ethyl alcohol during fermentation.On the other hand, there has been severe criticism of Lebedev'shypothesis that the hexoses break down to trioses, which are thenconverted into alcohol and carbon dioxide.The formation of hexosephosphoric acid was, of course, estab-lished by Harden and Young, but it is regarded by Neuberg as apathological phenomenon and not as a true intermediate process inthe living yeast ~011.5 I n this investigation, the formula ascribedby Harden and Young to hexosephosphoric acid, C,H,,O,(PO,H,),,has been confirmed, and further properties are recorded. It can-not be fermented by living yeasts even in the presence of co-ferments or artificial activators, nor can its salts.Further work has been done on the nature of the co-ferment.Examination has been made of the hypothesis that a mixture ofketonic acids and potfassium phosphate acts as a co-ferment, andthis has been confirmed;6 here, however, the evidence is not re-garded by Harden as sufficient. A large number of aldehydesaccelerate f ermentation.7Two important, papers have appeared on the enzymes concernedin the decomposition of dextrose and mannitol by Bacillus colicomrnunis.8 The view is taken that the fermentation of carbo-hydrates by bacteria is effected by a definite set of enzymes whichact in the same way in all cases. A common intermediate sub-stance is therefore assumed, the production of which may requirespecial enzymes, but the subsequent stages are always similar.I n development- of this view, it is shown that alcohol, acetic acid,and succinic acid are probably formed from the common inter-mediate substance by one reaction and lactic acid by another, eachaccelerated by specific enzymes.Papers have appeared on yeast metabolism, which, however, aredealt with in the section on Physiological Chemistry.A bacterial catalase has been described.9E. J. RUSSELL.C. Neuberg and E. Reinfurth, Bioclbern. Zeitsch., 1918, 89, 366, ; A . ,C. Neuberg, A. Levite, E. Flirber, and E. Schwenk, ibid., 1917, 83, 244 ;C. Neuberg, ibid., 1918, 88, 145 ; A., i, 469.E. C. Grey, Proc. Roy. SOC., 1918, P I , 90, 75, 9 2 ; A., i, 144.i, 517.A . , i, 91.!'M. Jacoby, Biochern. Zeitach., 1918, 88, 35; 89, 350; A., i, 469, 517

ISSN:0365-6217    

DOI:10.1039/AR9181500172

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

RADIOACTIVITY.THE Annual Report this year comprises the work done in 1917 and1918, and is, as regards the work published in Germany andAustria, subject to limitations imposed by the censorship in thesecountries, although probably most of the investigations in thisfield are included. The most important advances are concernedwith the discovery of the parent of actinium, which, in additiont~ adding an interesting, chemically new, element? to those dis-covered by radioactive methods, completes probably the longsequence of changes suffered by the radio-elements ; very comprehensive researches on the y-rays of radium, which throw much freshlight on the peculiarities observed in the absorption of these radia-tions and on their wave-length; and a notable beginning in theapplication of the Rutherford-Bohr model nuclear atom to thewhole of the elements, preserving the best features of the originalThomson electronic atom, from which new experimental inquiriesmay be expected to originate.The Parent of A ctimium .Ekatarntntum, .The most probable mode of origin of actinium as a branch pro-duct of the main uranium-radium series has already been fullydiscussed and illustrated by a diagram.1 It was expected thaturanium-P, isotopic with uranium-X, and ionium in the thoriumplace in the periodic table, and simultaneously formed with oneof them in the dual a-ray change of either uranium-Z oruranium-ZZ, would prove to be the first, member of the actiniumseries. Uranium-P gives a &radiatlion, and theref ore its unknowiiproduct must occupy the ‘ I ekatantalum ” place in the periodictabIe, and be isotopic with uranium-&, or brevium, the very short-lived product of uranium-X’, in a &ray change.If this unknownproduct of uranium-P underwent an a-ray change, the productmust be actinium or an isotope, and, if the chacge were slow, it1 Ann. Report, 1913, 267.H Z 1 9.would account for this member not having been ijreviouslyobserved; but in this case i t must be present in weighable quantityin uranium minerals.I n one investigation,z the hypothetical element was sought* for inpitchblende by subjecting it to a treatment which had been foundto be effective in volatilising its isotope, uranium-X2, fromuranium-X,. It was found, by distilling a preparation ofuranium-S in a current of air and carbon tetrachloride vapour a tan incipient red heat, that uraniuni-X, could readily be volatilisedfrom uranium-S,. On applying the method to about 500 gramsof a very rich Indian pitchblende, sinall sublimates were obtainedin which the known pre-emanation members could not be detected,but in which the post-emanation members, polonium, radium-3,and probably radium-D, werel present.The growth of actiniumin these preparations was tested f o r by means of the active depositproduced. At. first, all the preparations were free from actiniumand gave neither an emanation nor an active deposit. The firstpreparation, obtained during the first twenty hours of the sub-limation process, remained free from actinium. The second pre-paration was obtained by a simple continuation of t.he process atthe same temperature for a further period of ninety hours, andthis, in the course of 1000 days, continuously produced a distinctquantity of actinium, unmistakably characterised by means of theactive deposit.At the end of this period, the quantity ofactinium present was at; least twenty times as greatl as sufficed fordetection, A third sublimate, obtained by a furt"her treatmentof the inaterial for six hours atl a much higher temperature,remained free from actinium. Confirmation was obtained by thegrowth of actinium in another preparation, derived, from the in-soluble matter that had slowly deposited from a nitric acid solu-tion of Joachimsthal pitchblende on long keeping, by the carbontetrachloride sublimation.Moreover, certain old uranium-X pre-parations, separated from 50 kilograms of uranyl nitrate in 1909,in which a growth of actinium too minute t o be conclusive hadbeen recorded in 1913: by 1917 were found to contain actiniumin increased amount., minute, but beyond all doubt.The attempt. was made, on the admittedly uncertain assumptionthat the whole of the ekatantalum had been separated from themineral and was contained in the second sublimate-since nonewas found in the first, and the third, prepared by raising thetemperature considerably, also remained free from actiniuni-toobtain an estimate of the life-period of actinium. The case pre-F. Soddy and J. A. Cranaton, Proc.Roy. SOC., 1918, [A], 94, 384; A . ,ii, 211. F. Soddy, Chem,. News, 1913, 107, 97HADIOACTIVI’I‘T. 197sellts colnp!ete analogy t o the iiiethod used by Rgtherford and Bolt-wood t o find the life-period of radium, by separating the whole ofthe ionium from a mineral and determining the rate of grolvthfrom it of radium, in terms of the equilibrium amount of radiuminitially present- in the mineral.4 On the assumption that thewhole of the parent has been separated, the method gives the periodof the product. although nothing is known as to the period of theparent. It was found that the amount of actinium formed in2.5 years from t-he ekatantalum preparation was equal to theamount’ of actinium in one two-thousandth part of the originalmineral wed in the preparatioii.This gives for the period ofaverage life of actinium 6000 years. It is the iliaximum possiblevalue, to be reduced in proportion as the separation of the eka-tantalum from the mineral was incomplete. The iniiiiinum period,on the other hand, is given by the iiicomplete and preliminaryobservation of Mme. Curie, that the &activity of an old actiniumpreparation had decreased 10 per cent. in three years, from whicha period of average life of the order of only thirty years is t o beinferred.5In an independent investigatioii, the parent of actinium hasbeen separated from uranium minerals and given the name (‘ proto-actinium.” 6 A t the outset, these investigators state that they haveconfirmed Mme. Curie’s est-imate, that the period of actinium is ofthe order of thirty years, by observatioiis on the decay of theradiation over a period of seven years, as well as for several morerecently prepared specimens.This, if correct, indicates that8 inthe carbon tetrachloride distillation less than 1 per cent. of t.hecontained ekatantalum was removed. So that there is a t presenta real conflict of evidence as t o the period of this element, whichstill, after so many years, remains the chief lacuna in our know-ledge in this field. However, it is a step in the right directiondefinitely t o have confined it between the limits of thirty and 5000years.I n this investigation, the siliceous reidues reniaiiiiiig u11dis-solved after treatment of pitchblende with nitric acid providedthe raw material for the search for the parent of actinium.Asmall quantity of a tantalum compound was added, and thematerial treated with hydrofluoric acid. The filtrate, afterevaporation with sulphuric acid to dryness, was digested with con-centrated nitric acid. The part undissolved, containing the tan-talum, was examined first as regards its a-radiation. It, was foundto be giving an a-radiation, which increased with lapse of time.Coinpare Anj~. Rrpori. 1916. 265. -4nn. Rcport, 191 1, 2900. Hahn and L. Meitner, Physikal. Zeitsch., 1918, 19, 208 ; A . , ii, 34198 ANNUAL LCEPJOlt’l’S OX THE PROGRESS OF CHEMISTRY.On the expectation that the initial rays were due to the parentof actinium, and that these would be of low range in comparisonwith those later produced, derived from the products of actinium,the radiation was also examined under conditions such that therays of lower range were suppressed.The expectation was con-firmed. Under these conditions, the longer range a-rays wereabsent initially, but rapidly developed and grew in strength withlapse of time, With larger quantities of material, prepared in thesame way, the growth of actinium was definitely established by theappearance, and increase in amount with lapse of time, both ofthe short-lived actinium emanation and the characteristic activedeposit.A careful determination was made of the range of the a-raysinitially given by the preparation. The value obtlained, 3.314 cm.of air a t N.T.P., enables a rough estimate of the period of thenew member to be determined by means of the Geiger-Nuttallrelation.Unfortunately, the act-inium series does not obey thisrelation nearly as closely as the other disintegration series, andthere is a considerable difference in the constants, according asactinium-X or radioactinium is taken for the comparison. Fromthe former, the range corresponds with 1700 years, and from thelatter with 260,000 years, as the period of average life of proto-actinium.It is clear from this evidence, however, that the period of eka-tantalum or protoactinium inustl be such as to cause the equil-ibrium quantity accumulating in uranium minerals to be of thesame order as for radium. This quantity, relative to that ofradium, is as the ratio of the periods multiplied by 8/92, thebranching factor.Since the new element occupies a place to itselfin the periodic table, save for the hopelessly short-liveduranium-X2, or brevium, it should possess unique chemicalcharacter and spectrum. Its separation from uranium mineralsin a pure state, in quantities that’ will allow its atomic weight-and spectrum t o be determined and its various compounds to beprepared and stmdied, may theref ore be confidently anticipated.This, in turn, will allow the preparation of actinium, in a mannersimilar to the preparation of radiothorium from mesothorium, t.0be carried out, and will much simplify the elucidation of theproblems with regard to the period, atomic weight-, and spectrumof that element which remain to be settled.There is no reason t o doubt that ekatantalum is the product ofuranium-P, but this probably, as in the case of the production ofuranium-ZI from uranium-X2, can never be the subject of directproof owing to the unfavourable relations of the periods.TherHADIUACTIVl’IY. 199remains the doubt, however, as to whether uranium-P is the pro-duct of uranium-Z or uranium-IZ, although the latter is perhapsthe more probable. This point can only be settled by the deter-mination of the atomic weight of ekatantalum or actinium. Thefirst alternative makes the atomic weighis 234 and 230, and thesecond 230 and 226, respectively.I n this connexion, a third very interesting alternative sugges-tion has been made, namely, that actinium is derived from a thirddistinct isotope of uranium, of atomic weight 240, which does notbelong to the uranium-radium family a t all, but is a distinctprimary radio-element, for which the name actinouranium ” isproposed.7 I n support of this view, it is pointed out that thelatest determination of the atomic weight of uranium by Honig-schmid, 238.16, corresponds exactly with what it should be wereit, a mixture of 92 per cent.of an isotope of atomic weight 238,corresponding with that of radium. 226.0, and 8 per cent. of anisotope of atomic weight 240, corresponding with an atomic weight,of actinium, 232. Also, the fact that in the graph of the Geiger-Nuttall relation the t-hree series are not superimposed, but giveparallel lines, the constants being the same for each series butdifferent for the different series, is evidence that the actiniumseries is a distinct primary series.The obvious objection is that,so far as is yet known a t least, the ratio of actinium to radium inuranium minerals is constant, and, for this to be the case, actino-uranium must have the same period as uranium-I. This question,alsb, must await for its answer the determination of the atomicweight of either ekatantalum or actinium; but it may be notedthat, but for the assumed difference in the atomic weight;, no ex-perimenta! decision would be possible. There is no method of dis-tinguishing between a single substance disintegrating dually togive two products and a mixture of two isotopes in the proper pro-portion, each isotope having the same atomic weight and the sameperiod, although, of course, it would be an extremely unlikelychance that the periods of the two: components of such a mixturewould be the same.Except for the decision between these three alternatives, it maythus be considered fairly probable that the complicated disintegra-tion sequences of the radio-elements are now completely unravelled.Adopting as the most probable alternative that uranium-P is ‘pro-duced from uranium-ZZ, these sequences are illustrated in theaccompanying figure, taken from a recent lecture to the ChemicalSociety.s The figure is t o be read a t an angle of 45O; the number’ A.Piccard, Arch. ScL phy8. nat., 1917, [iv], 44, 161 ; A., ii, 6.* 3’. Soddy, T., 1919, 116, 1above or below each symbol indicates the period of average life, a? signifying that the period is indirectly estimnt,ed from the rangeof the a-rays.The figures at. the head of each place are the atomicnumbers, as deteriniiied by Moseley from the wave-lengths of thR ADIOA CTIVLTT. 201X-rays characteristic 01 the elements, on the assumption that thatof aluminium, the thirteenth element in the list of known elements,is 13. It is to be noted that, should the stellar elements ofNicholson find places in the periodic table, these numbers will haveto be increased. Of the twelve places between thallium anduranium covered by the disintegration series, two are vacant. Thechemical and spectroscopic character of each of the individualmembers of the series is that of one of ten elements, of which fiveare common elements-uranium, thorium, bismuth, lead, andthallium-thoroughly well known before radioactivity was dis-covered, two are equally well kii own-radium and emanation-andonly three, polonium, actinium, and ekatantalum, remain to beisolated in quantities sufficient for the spectrum and other proper-ties to be determined.Apart from the great theoretical advancesdue to the explanation of the natme of radioactive change, theenormous simplification effected in the practical and technical’problems connected with the preparation of the various membersin the concentrated conditions from radioactive minerals must noth e overlooked.The Isotopes of Lead und Uraniwm.In connexion with the determination of the atomic weights oflead derived from radioactive minerals,O one new atomic weightdetermination of thorio-lead has to be recorded.10 This specimenof lead was prepared from B Norwegian thorite from Langesund-fiord, and contained 30.1 per cent. of thorium, 0.45 per cent.ofuranium, and.0.35 per cent. of lead. The Th/U ratio, 67, was thussomewhatl higher than that, 57, for t.he lead from Ceylon thorite,which gave the value 20’7.7’7 for the atomic weight. The valuein the present case was found by Honigschmid to be 207*90st0-013,and this is the highest value yet actually found for the atomicweight of this element,.I n an attempt to obtain evidence as to whether common lead,with the atomic weight 207.2, is a single isotope or a mixture ofthe two derived from uranium and thorium, a comparison wasmade of the P-act-ivities and the atomic weights of the containedlead from a number of uranium minerals of the same geologicalage.10 The last-mentioned condition being satisfied, the P-activi-ties, being derived from the lead isotope, radium-D, are a measureof the uranio-lead to total lead ratio for the mineral.This ratiowill decrease, and the atomic weight of the lead increase, in pro-9 Ann. Report, 1916, 247, 272.10 K. Fajans, Zeitmh. ElPktrochm., 1918, 24, I63 : A . , ii, 421.H202 ANNUAL REPOKTS ON TEE PROGRESS OF CHEMISTRY.portion as the lead separated from the mineral has not been pro-duced from uranium, but is due to admixture. For three speci-mens of lead, derived from Joachimathal pitchblende, the valuesfound for the atomic weights, 206.405, 206.61, 206.73, and for the&activities, in the ratio 1 : 0.639 :0-55, were such as are to be ex-pected if the lead were a mixture of uranio-lead and common leadof constant atomic weight 207-2.The question, however, whetherordinary lead is a definite single isotope o r a mixture of isotopes ofdifferent atomic weights is likely to prove a difficult one. The con-stancy of the atomic weight of ordinary lead, as obtained from allsources, except the radioactive minerals, and even the proof that inthe latter case the lead was a mixture of that derived from theradio-elements with ordinary lead of this constant atomic weight,although valid enough evidence pointing to the homogeneity ofcommon lead, does not entirely settle the question, for it is possiblet o conceive of evolutionaiy processes in which different isotopes ofthe same element result necessarily in constant definite proportions,so that the product would simulate a homogeneous element.It was pointed out by A.Holmes that the age of the Ceylonthorite, from which lead of atomic weight' 207.77 was obtained, ascalculated from the Pb/Th ratio, namely, 130 million years, wasvery much lower than is to be expected. A Ceylon pitchblendefrom the same locality, which he regarded as likely to be of thesame age and as one of the most suitable minerals from which t ocalculate the age, had a Pb/U ratio 0.064, which corresponds withthe geological age, 512 million years.To account! for this and forthe general poverty of thorium minerals in lead, which was thereason for the original conclusion that lead could not' possibly bethe ultimate product of thorium, it has been suggested that onlyone of the two isotopes of lead derived from the thorium series ispermanently stable. The branching of the thorium series, as canbe seen from the figure, results in the production of two isobaricisotopes with atomic weight 208. Since different amounts ofenergy are evolved in the two branches, the two products are notidentical, and are likely to have different stabilities. If we takethe analogy of the radium series, the isotope formed in major pro-portion, namely, the one in the 65 per cent. branch, is analogousto radium-D, which is not permanently stable, but disintegratesfurther, and, after one a- and two &ray changes, finally gives theultimate product of atomic weight 206.Such further changeshave not yet been detected in the case of thorium, though, nowthat they are foreshadowed, it should be easy to decide definitelywhether or not they occur. An important point is that in 20 kilo-grams of this thorite neither bismuth nor mercury could bKA DIOACTIVITY. 20;:detected, These are the two elements which would result from asingle P - or a-ray change respectively. A successive a- and &ragchange would result i n thallium being produced, which was presentin the thorite in quite noticeable amount. An examination of theT1/ Th ratio of minerals, and of the radioactivity of thorio-lead, isthus called for, but the war has hitherto prevented the suggestionbeing put to the test.Assuming that only the 35 per cent.isotope of lead is per-manently stable, the calculated age of the mineral is 375 millionyears, which is much more in accordance with the geologicalevidence. A further point is that the atomic weight found for thelead, 207.77, is less than it should be if the lead is wholly of radio-active origin and if both isotopes survived, but agrees exactly withthe calculated value if only the 35 per cent. isotope is stable andhhe true atomic weights of uranio- and thorio-lead are exactintegers, 206 and 308 respectively.ll On the other hand, the morerecent determination of the atomic weight, 207.90, for the leadfrom Norwegian thorite is about, 0.08 too high on these assump-tions.Solubility of Salts of Isotopes.-It is to be expected that themolecular solubility of the salts of different isotopes will be thesame, and therefore that, for salts of isotopes of different atomicweight, the solubilities and the densities of the saturated solutionswill be different. A first attempt to put this to the test wasrecorded last year -14I n a second investigation,ls lead of atomic weight 206.42 wascompared with ordinary lead, and the molal solubilities of thenitrates a t 2 5 O were compared by estimating the lead in the solu-tions gravimetrically to the highest possible degree of accuracy.The result established conclusively that the mdal solubilities of thetlwo salts were identical within the very small margin of experi-mental error, that of the common lead nitrate being 1.7993 andthat of the uranio-lead nitrate being 1.7991 gram-molecules perlitre.With regard to the actual weight of lead per 100 grams ofwater, the figures, 37.281 for commoii lead and 37.130 for uranio-lead, are in substantially the same ratio as the known atomicweights.On the same two specimens of lead nitrate a careful comparisonof the refractive indices of the solid crystals failed t o reveal anydifference. A t 20°, the value of nD for each was 1.7814.11 F. Soddy, Royal Institution Lecture, May 18th, 1917 ; NatuTe, 1917,18 T. W. Richards and W. C. Schumb, J . Ame-r. Chem. Soc., 1918, QO,99, 414, 433.1403 ; A., ii, 422.l a Ann.Report, 1917, 2.H* 204 A4NNUAL REPOR'I'S OX 'I'HE PROGRESS OF CHEMISTKY.Uranium-I and Uranium-11.-In this section an attempt toseparate the isotopes of uranium by diffusion methods may conveni-ently be referred to. There is a difference of four units in theatomic weight of uranium-Z and uranium-ZZ, and a separation byfractional diffusion should theoretically be possible. The relativerates of diffusion may, however, be expected to differ as the square-roots of the relative molecular weights, and even although the mole-cules diffusing are anhydrous, the difference to be expected betweenthe diffusion coefficients is less than one-half per cent. , whereas if themolecules of the salt, as is quite possible, ar0 heavily hydrated insolution, this small difference will be still further diminished.Thenew attempt, like earlier ones, failed to effect any separation. Onlyan abstract. of the work is available, in which it is stated that theexperiment showed that the difference in the diffusion coefficientscould not exceed 1.5 per cent. The case is, however, one of themost favourable for examination, because an alteration in therelative concentration of the two isotopes will cause a differencein the a-radiation of the tiranium.14Spectra of L e d Isotopes.-Previous work has shown that thespectra of isotopes, botlh the ordinary light spectra and the high-frequency or X-ray spectra, are identical within the limits ofdetection. As regards the high-frequency spectrum, this has beenconfirmed in a new instance t.0 a very high degree of approxim-ation.The t'wwo strongest. lines in the L-series of lead, the so-calleda- and &lines, were photographed on the same plate and underthe same coiiditions for two specimens of lead, one of at-omic weight206.05, from Mmogoro uraninit-e, consisting essentially of uranio-lead, and the other, ordinary lead. The wave-length of the lineswas found to be identical, within tbhe error of measurement, whichwas estimated as 0.0001 A.15On the other hand, for ordinary lead and lead of atomic weight206.34, estimated to contain one part of common lead to threeparts of uranio-lead, the identity of wave-length of the strongestline in the light' spectrum, of wavelength 4058, has been tested toa greater degree of approximation probably than has before beenattained.This line was photographed with a 10-inch planeMichelson grating in the sixth order, under conditions such thata single &tgstrBrn unit corresponded with a distance of nearly3 mm. on the photographic plate. The source of illumination wasthe Wali-Mohamed oxy-cathode arc in a vacuum, and, during theH. Lachs, 1M. Nadratomska, and L. Wertenstein, Con~pt. rend. SOC. Sci.WUTGUW, 1917, 9, 670; A., ii, 213.l6 M. Siegbahn and W. StenstrGm, Cornpt. rend., 1917, 165, 428 ; A., 1017,ii, 5241tADIOACTLV LTT. 205preliminary work, it was found that differences in the pressurecaused differences in the intensities of the lines analogous t o thatnoticed by Soddy for the line 4760.1 in his original comparison oft.he spectra of ordinary and thorio-lead.I n the actual determina-t,ions. the two lamps containing the two specimens of lead werefrequently interchanged in position. In every case, a minutedifference in the wave-length of the line in question was observed,amounting in the mean to 0.0043 ,&., the line in the case of uranio-lead having the longer wave-length, as is t o be anticipatedtheoretically. A remarkable feature of the experiment was thatthe line in question was shifted, not broadened. Since the uranio-lead employed was certainly a mixture with comnion lead, thisresult is somewhat unexpected. As the authors themselves remark,i t is well to await the result of entirely independent con-firmation before concluding that the very minute difference inwave-length observed is due to the difference in atomic weight ofthe two specimens.16G'eiwsis, Nature, arid Relations beta$ee,i the C;'he,micul Elemeuts.A number of comprehensive accounts of the recent advances,often accompanied by attempts, more or less ambitious and in-definite, to interpret the constitution of the atom and the inter-relationship of the elements, have appeared, but these can onlybe briefly mentioned.The niost promising direction of advanceseems to lie in the direction of the interpretation of the light andhigh-frequency spectra, and the modification of the Rutherford-Bohr atom t.0 bring it* into line with the facts, as regards theelements ot.her than hydrogen and helium, tot which its initialsuccesses were confined.This can niost convenient-ly be dealt within a separate section.The attempt has been made t o construct a, model satom whichshall explam in particular the chemical character of the elements.17The orbits of the outer valency electrons are regarded as beingi n general elliptical rather than circular. At the positaim ofaphelion with regard to the nucleus, they will be travelling moreslowly, and so be less resistant l o forces tending to remove &ernfrom the atom. Those elements with variable valency are con-sidered to have more elliptical orbits than those with co'nstantvalency, whilst for the argon gases the orbits are consideredl c M7. D. Harkins and L. drollberg, Pro(:.S a t . Acad. Sci., 1917, 3, 710:.-I., ii, 89; Compare T. 3%. Merton, Pror. Ho?y, Soc., 1915, [A], 91, 195; A . ,1915, ii. 119: Ann. Report, 1916, 248.l 7 A. I%-. Slewart, Phil. N u y . , 191 S, 1~ i], 36, 326 ; A . , ii, 395206 ANNUAL REPORTS Oh’ THE PROGRESS OF CHEMISTRY.circular. Following the work of Fleck, who showed that quadri-valent uranium has great chemical resemblance to thorium, notamounting to the complete identity displayed by isotopes, ananalogy is drawn between the vnlency changes of an element, forexample, between ferrous and ferric iron, and the successive pro-ducts of P-ray changes, in which the electron is withdrawn fromthe nucleus rather than from the external ring of electrons. Forthese successive products of f3-ray changes, possessing essentiallythe same atomic weight but different atomic number and distinctchemical character, the term isobccres is used.I n another paper, pointing out general relationships among theradio-elements, another type of model atom is advocated, and theconnection between the structure, chemical linking, valency, andelectrochemical character discussed.lB Lastly, another discussionof the periodic law and the probable genesis of the elements, deal-ing particularly with the accommodation of hydrogen, the rareearths, and the stellar e!emeizts of Nicholson in the table, and thenew views introduced by t-he study of radioactive change, may bementioned.I n this paper is contained a complete and independentsystem of nomenclature of the radio-elements, on a definite andconsistent basis.19X-Ray Spectra and the Coiwtitution of t h e Atom.20Bohr’s theory, applied t o the nuclear atom of Rutherford, ex-plained the complete series spectrum of hydrogen and one of thespectra of helium emitted when a single electron recombined withthe isolated nucleus.Itl also explained the nature and significanceof R, the universal frequency constant of Rydberg, and enabledthis to be calculated in terms OF other fundamental constants to avery high degree of approximation; but it did not give anytheoretical interpretation of series spectra in geiieral, qnd hithertolittle attempt has been made to give any conception of the detailedconstitution of the elements as a whole. It was based on the twofundamental assumptions (1) that in the normal state the electronswere arranged in rings round the nucleus such that each electronhad angular momentum nzwa2 equal to h/27r, where m is the mass,w the angular velocity of the electron, h.is Planck’s constant, anda is the radius of the orbit; (2) t.hat the line of a series was pro-$8 E. Kohlweiler, Zeitxh. ph,y.siknl. Chun., 1918, 92, 685 ; 93, 1 ; A , .ii, 286, 364.lg C. Schmidt, Zeitsch. anorg. Chem., 1918, 103, 79; A., ii, 305.20 I,. Vegard, Phil. Mag., 1918, [vi], 35, 293; A., ii, 144; Bw. Deut.9, 328, 344 ; .4., ii, 93, 94. physikal. Ges., 1917RADIOACTIVITY. 207duced, after the removal in some way of an electron from one ofthe rings, by its recombination in steps towards the broken ringbetween successive stability orbits, so that in one ,tep one quantumof energy, hi!, where v is the frequency, was radiated.Much mathe-matical work has since been done in generalising the theory andapplying i t to non-circular orbits by Bohr, Sommerfeld, Schwarz-child, and Epstein.The great. extension of our knowledge of the high-frequencyspectra of the various elements provides a further means of testingand extending the theory. One of the first generalisations, madeby Kossel in 1914, was that' the difference of frequency in the a-and &lines of the K-spectrum of an element was equal, veryapproximately, to the frequency of the a-line of the L-spectrum.This was interpreted by Bohr to mean that the d i n e of theK-spectrum was produced, after the removal of an electron fromthe ring next the nucleus, by its replacement by an electron fromthe second ring, the &line by its replacement by an electron fromthe third ring, and the a-line of the L-spectrum by the replace-ment of an electron in the second ring by one from the third.Recently, Debye,2* as the result of an analysis based on certainfundamental assumptions, has succeeded in proving that the inner-most ring of electrons, from which the I<-series originates, consistsof three electrons in the case of the elements bet,ween sodium andneodymium in the periodic table.For elements of higher atomicnumber than 30, the increasing mass of the electrons, due to theirvelocities increasing and becoming comparable with the speed oflight, introduces difficulties into the exact calculation of the wave-lengths of the radiations.Vegard, making different alternative assumptions, althoughfinally adopting the above conclusion as probably the one mostlikely to- represent the constitution of the innermost ring, showsthat the ring might be of four electrons, on the one further andphysically perhaps improbable condition, that the H-radiationoriginated in all four electrons being removed together and re-combining again as a unit to re-form the ring.He then proceedsto discuss the urigin of the L-radiation, and shows that it, is quiteimpossible t o derive it by any recombination to a system in whichthe angular momentum of each electron is h/27r: One of Bohr'sfundamental assumptions must be altered, and he assumes that theenergy of the electron is in general nh/27r, where n is an integerhaving increasing value as we pass from ring to ring outwardsfrom the nucleus, and to which he gives the name the quant-number.It is only for the X-radiation and for the ring next tiheP. Debye, Ph)ysikal. Zeitsch., 1917, 18, 276 ; A., 1917, ii, 434308 ANNUAL REPORTS Oh' THE PROGRESS OF CHEMISTRY.nucleus that the quant-number is unity and Bohr's origiualassumption applies.As the result of his analysis and Debye's work, the K-series isto be attributed tho a ring of three electrons nearest to the nucleus,for which the quant-number is unity. The L-series should be duet,o two rings, containing 7 and 8 electrons reapectively, for whichthe quant-number is two, and the M-series to a ring containing9 or 10 electrons with the quant-number three. The new homo-geneous J-radiation of BarMa and Miss White,22 which is morepenetrating e ~ e n than the li-radiatioii, aiid is excited inaluminium by X-rays of wave-lengkh 0.37 A,, he considers cannotbe formed by any external electronic system, but must arise fromelectrons forming part of the nucleus. If this is so, it is clearlyof fundamental importance, and, indeed, it is in this gradualsapping up to the nucleus of the atom as we pass from one externalelectronic ring to the other, and the hope itl arouses that this mayprove an avenue of approach to the problem of artificial trans-mutation, that the chief fascination in this field lies.Taking as a very legitimate and probable view that in passingfrom the lighter to the heavier elements the system of eleccronsround the nucleus of the lighter element is preserved int.act in theheavier and is' gradually built round it, Vegard putas forward thefollowing definite suggestions, combining the essential poiiits ofSir J.J. Thornson's electronic atom with the conception of thenucleus. The elenleiits from helium t o fluorine have an internalring of two electrons, the external system consisting of from 0 t o 7electrons, one being added for 'each element or for each step inatomic number. I n all cases the nucleus changes, of course, witheach change in the atomic number, the nett, positive charge of thenucleus being- equal t o the atomic number, but) the mass and cm-stitution of the nucleus, which has no influence on the chemicalcharacter, are not further considered.,4t neon the added electronis transferred to the innerrnost ring, which, from now on, poss'essesthree electrons; the outer ring of seven electrons is preserved intactas a new, complete second ring, from which the L-series originates.Since the K-series originates by transference of an electron frointhe second tQ t'he innermost ring, it should begin with the elementsodium, a result in agreement with experiment. By continuing theprocess, a t argon we have both L-rings with 7 and 8 electronsrespectively, and the L-series of radiations may be expected tobegin with the element potassium. In the long period from argonto krypton, a new ring of ten electrons is firstl completed by nickel,constituting the first M-ring with quant-number three. This i32 - C,, C i .Burkla and Miss 1111. 1'. V-hite. Phil. N a g . , 191 8, [vi], 34, 270KA DIOA CTI VlT Y. 209followed by the formation of a new ring of eight electrons, andthe process is repeated from krypton t o xenon. The next fourelement,s, from msium t o cerium, are formed normally, theexternal valency system a t the latter element comprising fourelectrons. From now it is supposed, to account. for the rare earths,that this external system is kept intact, and the new electronsadded go t,o produce a new inner ring, the members of which have:I smaller quant-number than those outside. At the end of therare earth elements t.his internal ring is complet-ed, and the newelectrons are added on as before.The electrons forming the outermost system, which coiidition theordinary chemical and electrochemical character of the element, areprobably connected together as a whole in some unknown way, andin these phenomena act together as a unit rather than asindividuals.Thus electro-affinity cannot be the measure of theenergy required t o remove one electron from the system, which isproportional to the ionising potential, a totally distinct quantity.The positive ray experiments of Sir J. J. Thomson have shown thatthe power of an atom to bind additional electrons does not followthe electro-affinity. The suggestion is put forward that the electro-affinity may be proportional to the energy required to remove anelectron when all the other electrons of the system are simul-taneously removed, which, according to Bohr, is equal to the kineticenergy of the electron.The mathematical analysis of this viewleads t.o the espected results as regards the passage from electro-positive t o electronegative elements as the number of electrons inthe outermost system increases, the elements with the more slowlymoving electrons being the more electropositive, and also t o thewell-defined increase in the electropositive character with increaseof atomic weight for elements of the same family. With regardto electric conductivit.y,~~ by means of the idea of atomic con-ductivity capacity, Benedicks has shown clearly that it must beregarded as a strictly periodic function of the atomic number.The atom is regarded as possessing an electric capacity C and t.0be in frictionless motioii between two parallel planes, between whicha certain potential is maintained.The electric conductivity dueto the atom, A*, is equal to the product of the capacity, C, and thefrequency, or number of oscillations it executes per second, v. Sothe atomic conductive capacity is derived from the atomic con-ductivity, K , by dividing it by the atomic frequency, v. Thisquantity, plotted against the atomic number, gives a sharplyperiodic curve, in every respect analogous to tihat obtained whenthe atomic volume is plotted against atomic weight. Vegard con-23 C. Benedicks, Jatwb.Hndioabtiu. Idlclctronik., 2916, 13, 362210 AK’NUAL REPORTS ON THE PROQRESS OF CHEMISTRY,siders that the main features of this curve are t o be expected onhis view of the atomic structure, and that a great increase inelectric conductivity is to be expected each time a new surfacering is commenced.With regard to the nucleus of the atom itself, and the mannerin which the contained electrons are disposed, the idea is put for-ward that for these the quant-number may be smaller than unity.There are difficulties in connexion with this view in that the veloci-ties of the electrons would exceed that of light if the quant-numberis made much less than unity. The y-rays are much more pene-trating than those of the K-series, and, like the new J-series alreadymentioned, must arise from the high-speed electrons within thenucleus.The line of shortest wave-length in the y-ray spectrumof radium-C, with wave-length 0.072 i., would be accounted forby assuming the e1ect”ron to move within the nucleus between circlesfor which the quant-numbers are two-thirds and one-half, and thenew ?-radiation of aluminium by supposing the quant-numbers tobe one-half and one-quarter. Without putting too much trust inthe details of this theory of atomic structure, i t presents us forthe first time with a picture of the possible constitution of all theelements from one end of the periodic table to the other, which,however imperfect it may prove, is a t least definite and capableof detailed quantitative examination and improvement as ourknowledge of the high-frequency spectra of the elements grows.The New J- nizd ( 1 ) I-Series of Characteristic X-Radiations.24-With regard t o the new J-series of characteristic X-radiations,already referred to, these were put into evidence by determiningthe mass absorption coefficients in aluminium, paraffin wax, filterpaper, and water of X-rays of wave-lengths between 0-51 and0-145 A., and then plotting these against’ those found for copper.for which no J-radiation is expected to be excited by X-rays of thisrange of frequency.Discontinuities in the curves a t wave-lengths0-37 for water, due to oxygen, and 0.42 for filter paper, dueto oxygen and carbon, the latter discontinuity being marked alsofor paraffin wax, and a t 0.37 8.for aluminium, revealed the exist-ence of the new characteristic radiation, and the wave-lengthsgiven correspond with these of the rays for carbon, oxygen, andaluminium, the effect of hydrogen in the compounds being neglig-ible. These rays are a link between the K-series, the highestseries of characteristic X-rays previously known, and the y-rays ofradioactive substances. It is just possible that’ a still higher series,an Z-series of characteristic radiations, exists, but this has not yetbeen definitely shown.34 C. G. Barkla and Miss M.-P. White, Phil. M q . , 1918, [vil, 34, 270KADIOACTlVITY. 211Atomic Weight of Nebulium.26-By taking into account the mag-netic as well a8 the electrostatic forces acting on the electrons inthe atom postulated, the atomic weight of this element has beendeduced, from the wavelengths of the two principal lines in thespectrum, 5006.89 and 4363.37, to be 1.31, with a possible un-certainty of one unit in the last figure.The */-€days of Radium.From the newer point of view that the characteristic X-radia-tions of the various elements in the several series are due t o thesuccessive rings of electrons surrounding the nucleus, the wave-lengths of the radiations becoming the shorter and the rays themore penetrating the more nearly the nucleus is approached, they-rays appear to arise in a precisely analogous manner from rings ofelectrons contained within the nucleus.A clearer pict'ure of theirnature and origin is beginning to be formed.In the first place, a very comprehensive and fruitful re-examina-tion of the absorption of the y-rays of radium by matter, and ofthe questions connected with their homogeneity and the '' harden-ing" they undergo during the process of absorption, has been madewith a very much larger quantity of radium-0.12 gram of radiumchloride-than has before been available, which has greatlyfacilitated the clearing up of the points that the most careful workby private investigators with smaller resources left unsettled .26This work is to be interpreted in the light of the definition con-sistently adopted as to what is meant by absorption.Whether theenergy of the beam is lost by conversion into heat, electronic orwave-radiation is regarded as irrelevant.The diminution of theenergy over the area of the beam in its initial direction, whetherby scattering, deflexion, or actual absorption, is regarded as absorp-tion, as if; is considered that only when scattered or secondaryradiatJoii is eliminated or corrected for can true absorptioncoefficients be obtained and t~he quest'ion of t-he complexity or homo-geneity of the beam decided.With the large quantity of radium, a narrow cone of y-rays couldbe employed, which, after penetrating the absorbing plates, could25 J. W. Nicholson, Month. Not. Rog. A&. Soc., 1918, 78, 349 ; -4., ii, 181 ;compare Ann. Report, 1916, 256.26 K. W. F. Kohlrausch, Jahrb. Radioabtiv. Elektronik., 1918, 15, 64 ;also Wiener Ber., Mitt. Ra.-Inrrt., Nos.97, 98, 99, 102 ; Physikal Zeitsch.,1918, 19, 345 ; A., ii, 386. For accounts of-the earlier work, compare Ann.Report, 1910, 268; 1912, 280; 1912, 296, 306; 1913, 281 ; 1914, 276;1916, 262212 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.be passed through a magnetic field to eliminate electronic radia-tion, and the distance of the measuring instrument from the absorb-ing plates could be varied up to a metre if required. Many of thepuzzling effects before encountered, when the cone had to be of wideangle and the screens close to the electroscope, at once became clear.Thus, when a plate of copper 0.4 cm. thick was introduced intothe nearly parallel beam, and the distance of the ionisation vesselvaried from 0 t o 100 cm., the value of the absorption coefficient,p, for copper varied from 0.284 t o 0.522 (cm.-l) as the contribu-tion of the scattered and secondary y-radiation from the absorb-ing plate to t.he ionisation decreased with the distance.In thesecircumstaiices, the “hardening ” effect became constant’ after atlhickness of 3.3 cm. of lead or its equivalent had been traversed.Thus, the absorption coefficients for the unscreened rays were 0.176for aluminium, and this diminished to the constant! value 0.125when thicknesses of lead were introduced, no further change takingplace after 3.3 cin. of lead. Similarly, the absorption coefficientfor lead became constant after 3.3 cm. at 0.543. This value ishigher than the most trustworthy value previously adopted, 0.500,owing t o the difference in the conditions of measurement and theexclusion of the scattered and secondary radiation.The absorption curve below the thickness of 3.3 cm. of lead wasthe sum of two exponential curves, the value of the coefficientsbeing 0.543 for the more penetrating rays and 1-43 for the lesspenetrating rays, the ratio of the ionisations produced by the tworadiations in the initial beam being as 1.3 : 1.For lighter metals,a third still softer radiation, absorbed in 3 mm. of lead, with thecoefficient 4.6 in lead, was recognised. The general result of theanalysis was t o separate the y-rays of radium into three homo-geneous types of radiation, designated, in order of diminishingpenetrating power: K l , K2, K,, with ionisation energies in the ratio8: 6 : 1, and with absorption coefficients pl, p2, p3, as given forlead, 0-543, 1-43, 4.6, and for aluminium, 0-127, 0.230, 0.57(cm.-1).It will be observed fhat the ratio of the absorptioncoefficients is nearly twice as greatl for lead as for aluminium, whichis a general feature of these very short waves.Another point is that?, so far as ionisation is concerned, the mostpenetrating radiation is the mostl powerful, and this no doubtexplains to some extent the earlier conclusiorl that the rays wereabsorbed by lead, after the first centimetre, as a homogeneous radia-tion. The explanation of the definite conclusion of F. and W. M.Soddy, from experiments on the absorption in truncated hemi-Rpheres in a hemispherical ionisation chamber, capable of exact~nat.heinatical reprecentation and investigation, that the radiatioRADlOACTlVlTY. 21 3was absorbed as a homogeneous beam, without scattering and pro-duction of secondary radiation, is not so clear, but is ascribed t o abalancing of opposite effects.The heavy elements, which give riseto relatively little secondary radiation, absorb the less penetratingradiation the more strongly, whilst the lighter elements, whichabsorb the less penetrating radiation relatively less strongly, giverise to a strong secondary radiation. In the ordinary disposition,with absorbing plates close to an ordinary electroscope, thelogarithmic absorption curve is, for light metals, slightly concave,and, for heavy metals, slightly convex t o the origin.As regards the values of the mass absorption coefficients, PIP,where p is the density, for K , the extreme variation for differentelements is only 15 per cent.., the elements of mean atomic weight,as previously established, having the smaller values.Tin has theminimum value, about 0.04, which increases both for the lighterand the heavier elements. For K,, the behaviour is moreirregular, or perhaps to some extent a periodic function of theatomic weight". The value for the heaviest element, bismuth, 0.17,is about twice that for the lightest, aluminium, 0.085.The full identification of these three types of ./-rays disclosed byt'he absorption phenomena with those disclosed by the crystalreflection method27 is not yet possible. Using a linear relation ofSiegbahn between the logarithm of t'he absorption coefficients inaluminium and the logarithm of the wave-length of the character-istic X-radiations of the various elements, and assuming what,according to the work of Barkla and Rutherford, is certainly noteven approximately true, that; this may be extrapolated into theregion of very short waves, the values calculated for the wave-lengths are: f o r K , 0,139, for K2 0.174, and for K , 0.240 8.iTtiis regarded as almost certainly the most penetrating type of y-raygiven by radium-3, and K , as the doublet, with wave-lengths0.159 and 0.169, as measured by Rutherford and Andrade, ofwhich one component was regarded as probably due to radium-Band one to radium-C. K2, moreover, is considered as almostcertainly the d i n e of the K-series of the characteristic X-radia-tion of bismuth.Kl does not, however, correspond with the mostpenetrating rays of wave-length 0.099 and 0.115 in the y-rayspectrum of radiumC. I n view of the recent conclusion of Ishinoand Rutherford, still to be dealt with, that the penetrating y-raysof radium4 are of very much shorter wave-length than any t*hathave been resolved by crystal reflection, this whole attempt toCOrrelate the results O€ t'he ahsorption and spectrnm analyses musthe regarded as doubtful,Ann. Report, 1913, 282 ; 1914, 276214 SNNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.In another investigation, also with a large quantity of radium 28and with a similar experimental disposition, the separate coefficientsof scattering and absorption were determined for rays that hadpassed through 1 cm.of lead. As regards the total emergentradiation, the rays are absorbed exponentially, and the obFervedcoefficient is the sum of the true absorption and the scatteringcoefficients. When the absorbing plate is atl a sufficient distancefrom the electroscope, so thatl the amount of scattered radiationentering the electroscope may be considered negligible, the coefficientof the absorption curve is that of true absorption alone. Thisneglects the increased absorption suffered by the scattered radiationin the plate, due to the thickness traversed increasing as the raysbecome oblique to their initial direction, but becomes the morenearly true as the absorbing plates decrease in thickness.The ex-periments consisted in measuring the rays, confined to a narrow cone,,with the absorbing plate in three positions : (1) near the source farremoved from the electroscope; (2) close up to the front; of theelectroscope ; (3) close up behind the electroscope, and extrapolatingthe values found for the scattering and absorption coefficients t ozero thickness of absorber. As the final result, the value of thescattering coefficient., r, was taken to be 0.121 for aluminium,0.334 for iron, and 0.397 for lead, the corresponding mass scatter-ing coefficients, v / p , being 0.045, 0.042, and 0.034 respectively.For p and p / p , the values in these three metals were, respectively,0-070, 0.0263; 0.206, 0.0262; 0.460, 0.0423.These results are ofinterest in two directions. First, the scattering is very much lessthan for X-rays, for which it is practically independent of wave-length. For example, Hull and Miss Rice, using the X-radiationof a Coolidge tube, found that the true mass absorption coefficientvaried as the cube of the wave-length, but the mass scatteringcoefficient was 0.12, independent* of the wave-length. Since thetotal mass absorption coefficient found in these experiments withy-frays, 0-076 for lead, was less than the scattering coefficient forX-rays, it is clear that the results of Hidl and Miss Rice cannot beextrapolated to waves of shorter wave-length, and that for thesethe scattering coefficient decreases. The second point is that thevalue of the total absorption coefficient in lead for the X-rays ofwave-length 0-15 i.is some forty times greater than for the hardy-rays of radium, ( p + + ) / p being 3.00, as compared with 0.076.This makes it appear that the hard y-rays of radium4 consist ofwaves very much shorter than any that have yet been observed bythe crystal reflection method, the shortest? wbve-length so farobserved being 0.071 A.28 M. Ishino, Phil. Mag., 1817, [Vi], 83, 129RADlOA CTIVI'I'Y. 215These conclusions have been further developed by an examina-tion of the X-rays from a Coolidge tube, generated by voltagesbetween 79,000 and 196,000.29 A t the highest voltage, theabsorption in lead could be followed over a range of 10 mm., butthe intensity was cut down to less than one-millionth of the initialvalue by this thickness, although for the y-rays of radium sometwenty times this thickness would be necessary to produce prac-tically complete absorption.Confining attention to the total massabsorption coefficients, ( p + o ) / p , between the extremes of voltagementioned, this changed from 2.37 to 0.75. From 105,000 to144,000 volts, the rays were absorbed exponentially, and thiscoefficient remained constant a t 1.93. At 183,000 volts i t decreasedfrom 2.28 t o 1-05, as the thickness of lead increased from 0.7 to7.0 mm. The homogeneous radiation obtained a t intermediatevoltage is undoubtedly due to the characteristic radiation of wave-length 0.149 %., given by lead. After passing through screens ofiron, the values of (p +o) / p in aluminium for the end radiationwere 0-14, 0.11, and 0.085 for voltages of 92,000, 144,000, and183,000 respectively.The wavelength of the X-rays generated may be calculatedclosely from the voltage by the quantum relation E = hv, where Eis the energy of the electron impressed on it by the voltage, h isPlanck's constant, and Y is the frequency of the X-rays generated.These resulh showed thatl for high frequencies, the absorptioncoefficients, instead of varying a t something like the cube of thewave-length, as in the case of X-rays of lower frequency, vary butslowly with t.he wave-length, and that the wave-lengths of thepenetrating y-rays of radium4 must be a t least three times, andmay be ten times, shorter than the shortest revealed by the crystalreflection method.Using the quantum relation, the observedradium-C y-rays of wave-lengths 0-072 and 0.099 A. correspondwith a voltage of 174,000 and 125,000 volts. The values of (p+ v ) / pfor X-rays excited a t these voltages is 0.09 and 0.12. The mainy-rays of radium4 must correspond with X-rays excited a t between600,000 and 2,OOO,OOO volts, and their wave-length must lie between0'02 and 0.007 A., which is about a hundred times less than thewave-lengths of the soft y-rays of radium-B.An examination of the voltage necessary to give the electronkinetic energy equal to that possessed by the various groups ofP-rays in the magnetic spectrum of radium-B and 4 3 0 bears outthis conclusion. Of the three types of y-rays given by radium-B,3Q Sir E.Rutherford. Phil. Nag., 1917, [vi], 34, 163 ; compare also Silvanus30 Ann. Repwt, 1911, 278.P. Thompson Nemorial Lecture, J . Rdntgen SOC., 1918, 14, 75the softest, p=45 (cm.-I), in lead, corresponds with a voltage of200,000, and there are three strong groups in the &ray spectrumof radium-B, the energies of which correspond with an averagevoltage of 200,000. The most penetrating type, which is alsopresent in the y-rays of radium-C, p=1.5 in lead, corresponds witha voltage of 500,000, and &rays with energies appropriate to thisvoltage are well marked in the &ray magnetic spect'rra of bothradium-B and -C.Attempts to detect rays of shorter wave-length than those knownin the y-rays of radium-C by the crystal reflection method havefailed.Possibly the crystal is unable t o resolve waves so small incomparison with the grating-space. Rutherford now regards it asmore probable that the transformation between P - and y-raysoccurs by single quanta rather than by multiple quanta, and t,hatthe multiple relations observed bet'ween the energies of some groupsof fl-rays must indicate approximate multiple relations betweenthe frequencies of the y-rays. Assuming that the single quantumrelation holds, the magnetic spectrum of the fi-ra,ys should affordtrustworthhy data for extending the investigation of the X- ory-ray spectra into the region of Oery short wavelength, where thecrystal reflection method fails. If so, the extreme complexity ofthe magnetic spectra of the @-rays indicates that the spectrum ofthe y-rays, and presumably the high-frequency spectra of heavyelements in general, are in reality just. as complex as their ordinarylight spectra.The Actitqe Deposits.An investigation of the effect of different atmospheres on thedistribution of the active deposit in an electric field has showiithat the final condition of the particle, recoiling from the emana-tions after the discharge of the a-particle, has nothing to do withthe charge carried a t the instant of formation, but depends entirelyon the character of the gas molecules encountered during therecoil.31 I n dry air, all the particles of active deposit remainpositively charged, whereas in an atmosphere of pure ether vapour,and probabIy in pure water vapour, all remain uncharged.I n amixture of air and vapour, the proportion of charged to unchargedatoms depends on the proportion of air and vapour in the mixture.Hydrogen, oxygen, and carbon dioxide all behave like dry air inthis respect, whilst ethyl bromide vapour resembles ether.a1 G. H. Henderson, Tram. Roy. SOC. Calzccda, 1917, [iii], 10, 151 ; d.,1917, ii, 351 ; compare Ann. Report, 1926, 26311 h 111 OACT I 1’ I ‘IT. 217As regards the distribution of the active deposit in an electricfield, itl has also been shown that the phenomenon of the electricwind has much t o do with the results obtained.32 Thus, when theelectrodes consist of a sharp needle point opposite a disk and highpotentials are employed, the electric wind drives the depositl on tothe disk, independently of whether it is the cathode or t.he anode,provided that the gas is strongly ioniseid.This, for example, isusually the case when the experiment is made in a vessel muchused with the radium emanation, and on the interior surface ofwhich an active layer of poloninni has formed. By suitablyarranging the electrodes, the electric wind may cause a continuouscirculat-ion of the gas round a closed annulus. If into the gas astrong source of radium-A is introduced, radium-R particles, recoil-ing from i t and becoming discharged, remain in the gas withoutdepositing. These uncharged radium-B particles may be causedby the electric wind to go 011 circulating in the apparatus longafter the radium-d that gave rise to t?hem has all disintegrated,and may be made to deposit a t will by directing &hem t o a surfaceby the electric wind independently of the sign of the charge on thesurface.Similarly, tshe motion of the so-called large ions in theelectric field is t o be ascribed to the electric wind, and not, asformerly supposed, to their carrying an electric charge.Another curious and as yet* unexplained property of the radiumactive deposit is that, after it has been deposited on a disk, itspreads to a slight. extent t o surrounding surfaces, as if slightlyvolatile.33 Thus, i f a plate is mounted opposite to the disk coatedwith the active deposit, the plate being positively charged withreference to the disk to avoid radium-I? from being deposited 011it by recoil in the case that radium-A is present.in the activedeposit, the plate always acquires a small fraction of the sameactive deposit, as is present on t.he disk. This proportion is muchdecreased by washing t5he deposit on the disk or by gently heatingit, but is not much affected by the physical or chemical conditionof the surface of the disk or by directing on the coatliig of activedeposit’ a violent blast of air. When the exposure of the disk tothe emanation has been short, the proportion of active depositlost in this way is much increased, and, for exposures of only a fewseconds, it may become comparable with the amount of radium-Blost by recoil. The phenomenon constitutes a very insidious sourceof possible error in certain experiments.For example, the recoilof radium-C2 may be entirely niasked by it i f precautions are nottaken. A very remarkable point, is that, from radium-A, the32 8. Ratner, Phil. May., 1917, [vi], 34, 429 ; -4., 1917, ii, 568.33 Ibid., 1918, 36, 397 ; A., ii, 419318 ANNUAL REFORTS ON THE PROGRESS OF CHEMISTRY.quantity escaping from the disk diminishes in a regular mannerwith lapse of time, falling to half the initial value in 1.4 minutes,though the half-period of radium-A itself is three minutes.Although no explanation is advanced, the practical importance ofthe effect has to be borne in mind.Solubility of Pure Radium Su1phate.--It is a strange but seem-ingly well-established fact that, when a barium-radium solution isprecipitated by sulphuric acid or a soluble sulphate, there is nochange between the relative concentration of the radium andbarium in the fractions precipitated and left in solution, even whenthe precipitant is in excess.The behaviour, which has beentermed ‘‘ pseudo-isotopy,” resembles that of two isotopic elements,although barium is easily separable from radium.34 It suggeststhat the solubilities of radium and barium su1phat.e are the same,and this point has been investigated. The solubility of bariumsulphate in water a t 2 5 O is 2 . 3 ~ gram per C.C. A roughextrapolation from the solubilities 9 of the sulphates of calcium,strontium, and barium to that of radium sulphate indicates, forthe latter, a solubility of the order of 10-8.In the practical work-ing up of carnotite for radium, however, by the precipitation ofsolutions of radium, in the presence of a million-fold its weight ofbarium, by sulphuric acid, only same 10-ll gram of radium per C.C.is contained in the solution.The direct estimation was carried out by the fractionation ofsome 0.25 gram of radium in the form of bromide to 100 per cent.purity, which was checked by a comparison with the U.S.A. sub-standard. This was converted into the sulphate, and the solu-bility a t 2 5 O determined for 1 C.C. of the solution by the ernana-tion method, in pure water and in various concentrations ofsulphuric acid. The values obtained, between 2.0 and 2.3 ( x 10-8gram per c.c.), were constant in pure water and in sulphuric acidup to 50 per cent.concentration, but rapidly increased with higherconcentration, being twelve times as great for 70 per cent. as for65 per cent. concentration. The constancy of the solubility forlow concentrations of sulphuric acid is notablel. The case is oneof the clearest and most striking of that sharp chemical behaviourof radioactive substances in infinitesimal quantity in the presenceof an analogous element which has been so frequently remarked,and has made the practical chemistry of these substances so vastlys4 S. C. Lind, J. E. Underwood, and C. F. Whitternore, J . Amer. Chem. SOL,1918, 40, 465 ; A., ii, 14R A I) I 0 AC‘I’ I V ITT. 219easier than could have been anticipated. On thinking over thematter, the explanation that suggests itself is that radium andbarium sulphates are isoinorphous and constitute in the solid statea single phase rather than two phases.Series Spectrum of Radium.-There is no doubt that the atomicnumber rather than the atomic weight is the constant controllingmost nearly the chemical and spectroscopic character of theelements, and many approximate relations found to hold for theatomic weight have been reexamined for the atomic number.Byplott-ing the logarithms of the frequency differences between theextreme members of the triplets in the spectral series of theelements of the second family against the logarithms of the atomicweights, the alternate members have been found to fall on twostraight lines, the one cumprising mercury, cadmium, zinc, andmagnesium, and the other barium, strontium, and calcium.Byextrapolation, the frequency difference found for radium isapproximately 3060 i. In the radium spectrum there are anumber of triplets with average frequency differences 201 6.64 and1036.15, and there is little doubt that the sum of these, 3052.79,is a characteristic of the radium spectrum, although the conclusionstill had to be confirmed by magnetic resolution of the lines toascertain the series to which they belong.36TechlrLical Extraction of Radium from Curnoltite .-Some furtherparticulars are given of the results of tests on the working up ofcarnotite by treatment wit*h concentrated sulphuric acid, or fusionwith sodium sulphate, and fractional sedimentation of the productafter lixiviating with water, that have already in part? beende~cribed.3~ Allowing the coarse and finer sediments to settleseparately, 87 per cent.of the contained radium was present inthe latter, in which the radium was from twenty t o thirty timesmore concentrated than in the original ore. The sediment con-sisted of 90 per cent. of sand and 10 per cent. of sulphates, and afurther concentrafion of the radiuni from 150 to 300 times waseffected by solution in boiling concentrated sulphuric acid andreprecipitation with water containing a trace of barium chloride,or by fusion with sodium carbonate, and proceeding as in the moreusual method.“ The Milligram of riesothorium.”-A technically very importantquantity, and one that, by its nature, has proved difficult to connect35 Gladys A.Anslow mid Janet T. Howell, Prac. Nut. Acud. Sci., 1917Compare also H. Bell, Phil. Mag., 1918, [vi], 8636 A. G. Loomis and H. Schlunclt, J . Ind. Eng. Chem., 1916, 8, 990 ; A.,3, 409 ; A., 1917, ii, 401.337 ; A., ii, 383.1917, ii, 31. Compare Ann. Report, 1916, 269220 ANNUAT, REPORTS ON THE PROGRESS OF CHEMISTRY.with other radioactive quantities, is the so-called milligram ofmesothorium, meaning, thereby, the quantity of mesothorium-1 and-2 in equilibrium (actually, of course, unweighable) which has they-ray activity of 1 milligram of radium (element) in equilibriumwith its first four products and in the form of any convenient coin-pound. I n a long and difficult investigation into the relative con-tribution of the various members of the disintegrat'ion series ofthorium to the radioactivity of thorium minerals, it was foundthat the quantity in question was that in equilibrium with 19 kilo-grams of thorium in thorium minerals, the y-rays being measuredthrough 2 mni.of lead and 1.32 inrn. of brass. Therefore 1 gramof thorium in its minerals is in equilibrium with 0.524 x"milligram of mesothorium." whereas 1 gram of uranium in itsminerals is in equilibrium with 3-24 x 10-4 milligram of radium.Thus, to obtain preparations of the same */-activity, which is thebasis on which they are sold, six times as much thorium as ofuranium has t~ be worked up, which indicates sufficiently therelatively unf avourable position of the thorium minerals comparedwith those of uranium as sources of radioactive preparations, andto some extent discounts the advantage that in the case of thethorium the raw material is an otherwise valueless by-product3.37In the same work it was conaluderl that: of the y-activity of athorium iniiieral due t o thorium, 36.3 per cent.was derived frommesothorium and 62.7 per cent. from radiothorium, or, speakingmore strictly, from mesothorium-2 and from thorium-D respectively.Li f e-periods of Th o 1-i ic n z , Meso t hor i mi, aizd Radio t h orizirn .--Theperiod of radiothoriuni, according to a consensus of independentevidence, is somewhat less than that formerly accepted. The mostcareful and accurate determination38 gives 1.905 years, or 696days, for the period of half-change, or 2-75 years for the period 0'average life, with a probable accuracy within 1 per cent.For the period of mesothorium-Z a value was found, namely, 6.7years, much higher than tNhat, 5.5 years, usually accepted for thehalf-period, The new value, which was confirmed in independentexperiments and seems thoroughly well f ouaded, makes the periodof average life 9-67 years, the period for the maximum a-radio-activity of a mesothorium preparation due to the growth of radio-thorium, 4.83 years, and the maximum for the y-rays 3-34 years.For preparations of equal a-activity of (1) radium, (2) radio-thorium, (3) mesothorium in equilibrium with accumulated radio-37 H.X. McCoy and L. M. Henderson, J . Amer. Chem.Soc., 1918, M, 1316;38 L. Meitner, Physikal. Zeitsclb., 1918, 19, 257 ; A , , ii, 347 ; compareA . , ii, 422.B. Walter, ibid., 1917, 18, 584; A , , ii, 51thorium, the y-activities-are in the ratio 1.00 : 0.66 : 1.11. For theperiod of thorium itself, a higher value than is usually acceptedwas found by a long arid somewhat indirect method. The half-period found was 2-37 x 101" years, assuming that of radium to be1740 years, as compared wit.h previous values ranging from 1-28to 1.86 ( x 101O years).The B e c q o f Luminosity o j Endiiim-Zinc Szclphide Paint .-Theillcreasing use oE radium luminous paint in watches, compasses fornight flying, and the dials of instruments generally, has made thequestion of the decay cf the luminosity, due to the deterioration ofthe zinc sulphide exposed to the a-ray bombardment, of greatpractical importance.A description has been given of the methodsemployed a t the National Physical Laboratory for testing theluminosity of luminous preparations, both before and after applica-tion to the dials of instruments, of the considerations governingthe choice and specification of these preparations and of the instru-ment with which they are used, and of the decay of the luminositywith time. Through some effect of the medium used to fix thepreparation on t.0 the surface coated, probably in protecting thezinc sulphide to some extent from the a-ray bombardment, the rateof decay of the luminosity of the compound is only from une-thirdto one-foirth as rapid, after the paint has been applied, as it ishef ore application.On Rutherford's theory of the destruction of " active centresin the zinc sulphide by the bombardment, the luminosity shoulddecrease to zero exponentially with the time.I n practice, it isfound that, whilst this is true for the initial period, some 200 daysfrom manufacture, the rate of decrease then falls off and theluminosity then tends to approach a limiting value which is not~er0.39 A modification of the theory to account for this, that thereis a recovery of the destroyed active centres at a rate proportionalto their concentration, has been proposed and found to agree withthe experimental results in tche case of eight different samplesexamined. The expression connecting the brightness, Bt, a t anytime from preparation, t , with the time, t , is log(& - m) = Lt, wherem and t are constants.One conclusion of the work, which is ofpractical importance, is that no advantage commensurate withillcreased cost1 is gained by increasing the radium content above0.2, or a t mast 0.3 milligram of radium per gram of zinc sulphide.For fuller results of the decay of these preparations, the origin31rapers should be consulted.39 C. C. Paterson, J. W. T. Walsh, and W. F. Higgins, Proc. Physical SOC.J. W. T. Walsh, Proc. Roy. Soc., 1917, [A], 93, 550 ; London, 1917,29, 215.A., 1917, ii, 56922.2 ANNUAL ItEPOlt'J'S ON 'l'HE PROGRESS OF CHEMIS'l'KP.Effect of Radium Rays an Colloids.-Using preparations ofradium containing 0.1 gram of the element, some remarkable resultshave been observed of the effect of the B- and the y-rays on thecolloidal solution of ceric hydroxide, prepared by dialysing a solu-tion containing 10 per cent..of cerio ammonium nitrate. Thissolution, left to itself, ages with time, in that its viscosity decreases,and its liability to coagulate and its sensitiveness to electrolytesdiminish. These spontaneous changes, which are attributed togradual dehydration of the colloidal particles, are accelerated byrise of temperature and are not reversible. Exposure to the 8- ory-rays of radium a t first accelerated the diminution of viscosity,but, after that, the viscosity steadily increased to a very high value,and after many days a stable, clear jelly resulted.Once the increaseof viscosity has set in, it appears to proceed independently as towhether exposure to the rays be continued or not. I f , however,the irradiation is terminated before the initial diminution ofviscosity is completed, t'he viscosity rises abruptly, reaches a maxi-mum, and then decreases almost as abruptly until a value near theminimum is reached. A fresh exposure t o the radiation, afterquickly completing the reduction of the viscosity t o the minimumthat would have been reached by constant irradiation, thedgelatinises the solution with relatively great rapidity. The curveconnecting the viscosity and the time, as regards the abrupt riseto a maximum followed by the fall to a minimum value, is remin-iscent of the type familiar in radioactive change, such, for example,as would be obtained for the variation of the activity with thetime in the case of a radioactive substance, not itself giving rays,but producing a product, of period similar to its own, responsiblefor the radiation.The agent used, owing to the magnitude of theeffects and the apparent regularity with which they occur, seemsto be one well suited for the study of effects of this character, andthe results look as if they should be amenable t o strict mathe-matical interpretation, The effects of the rays are, in general,similar to those produced by minute traces of electrolytes in amountinsufficient to produce immediate coagulation. They differ, how-ever, in detail. JFor example, with electrolytes, the initial reduc-tion of viscosity occurs instantaneously, and the jelly finally pro-duced is unstable.40The explanation of Zsigmondy?l that the colloidal state of theactive deposits in neutral and alkaline solutions, recognised first byPaneth, may be due t o the adsorption af the radio-elements by40 A.Fernau and W. Pauli, Kolloid Zeitsch., 1917, 20, 20 ; A., 1917,ii, 189. 41 Ann. Report, 1913, 276RADIOACTIVITY. 223existing colloid particle; in the liquid, possibly derived from theglass containing vessels, has been criticised as inadequate, andfurther experiments carried out on the properties of the radiumactive deposit in various solvents.42 The proportions of the activedeposit obtained on the anode and cathode respectively, and theadsorption of the radioactive substances by various adsorbents,were both found to depend to a considerable extent on the natureof the solvent.Yleochroic Halos.43-A careful study of the appearance anddimensions of the pleochroic halos found in various kinds of micahas raised many new problems.Although the final stage ofthe halo corresponds with what might be expected, the earlystages of development, in which concentric rings appear, corre-sponding in radius with the ranges of the various u-particles con-cerned, are extremely difficult to explain. Because the outwardspreading of the rays, according to the square of the distance fromthe centre, ought so to weaken the darkening a t the edge, relativelyto that a t the centre, that the " corona " clue to radium-C oughtnever to appear before the centre has blackened up, whereas thiscorona is a well-marked feature in the early stages of developmentof the halo.In fact, the development is almost exactly what wouldbe expected for a parallel beam of a-rays rather than for rays pro-ceeding outward from a pointi source. To account for this, Jolyassumes that the more quickly moving ways, which reach to theedge of the halo, in their passage through the mica can reverse theeffect of the more slowly moving rays, much as the latent image in thephotographic plate caused by X-rays may be reversed by subsequentexposure to light. Whatever %he explanation, there is no doubtof the fact that the halos do develop in a regular sequence, thefirst effect being the appearance of .the central sphere due to therays of short range, followed quickly by the appearance of theouter concentric rings due to the rays of longer range.The micafrom a Vosges granite was found to be very rich in thorium halos,which, under the microscope, can readily be distinguished by theirdimensions from the mure common uranium halos, abundant inthe mica from the Leinster granite of County Carlow and fromBallyellen. In addition, one clear example of a mixed uranium-thorium halo was found, together with another class of halo,ultimately traced in its origin to the radium emanation by meansof its dimensions. The latter were found in conduits in the mica,43 L. Zachs, Kolloid Zeitach., 1917, 21, 165 ; A., ii, 95.48 J.Joly, Phil. Trans., 1917, [A], 217, 51; compare Ann. Report,1910, 260 ; 1913, 279224 ANNU.lL REPOH'L'S ON THE PROUKESY OF CHEMISTRY.through which water charged with radium emanation presumablyhad percolated, around some nucleus capable of adsorbing or retain-ing the emanation.A very careful and accurate series of measurements of the radiiof the component features of all these halos gave results thatagreed perfectJy with the known ranges of the a-rays and thestopping power of the mica, except' in one very significant, case.Whereas the outer features of the uranium halo exhibit- gootlcorrespondence, the inner features undoubtedly do not fit, thecentral portion beiiig distinctly larger in radius than is to beexpected from the range of the rays concerned in its production.I n attempting to account; for this, Joly advances the suggestionthat the period of uranium may have been shorter, and the a-raysexpelled therefore loager in range, in foriiier geological times thanis now the case.For the case of the thorium halos, there is NOreason to believe that the transformation has not proceededthroughout a t a uniform rate. The view, in the case of uranium,would also serve to reconcile the discrepancy between the radio-active and geological estimates of the age of the earth from thelead-uranium ratio of minerals. It is clear that! before, a sugges-tion so completely ati variance with what must be regarded as afairly well-founded conclusion can be accepted, much stronger andmore definite evidence will have to be put' forward.Scattehg of a-Particles by Gases.-A method has been describedfor determining the scattering of a-particles in gases, especially inhydrogen, by passing the a-rays from a fine needle point., coatedwith the active deposit., through a small hole and receiving themon a photographic plate a t a suitable distance in an apparatusthat can be filled with the desired gas at" suitable pressure.Thenumber of darkened silver grains in the photographic image canbe counted under the microscope, and since the number of grains,in general, is proportional to the number of a-particles, t,he methodcan be used for determining the deflections suffered by thea-particle i n its passage through the gas. So far, only preliminaryresults have beon 0btained.4~Bismuth Hydride .-A problem of chemistry that has beenpreviously much investigated without definite result, whetherbismuth forms a volatile hydride analogous to the compoundsformed by the other elements in this family, has been the occasionfor an elegant application of the conversion of a chemical into aradioactive problem by the use of a radioactive isotopic element.The C-members of the disintegration series are isotopic with44 R.R. Sahni, Phil. Mag., 1917, [vi], 33, 290; compare Ann. Report,1916, 261R A D I 0 A CTI V1 T 1’. 225bismuth, and, in the present case, thorium-C was chosen. Mag-nesium foil coated with the active deposit of thorium was dissolvedin acid and the evolved hydrogen passed into an electroscope, asin testing for an emanation.The gas showed distinct radioactivity,which was identified with that of thorium-C by its rate of decay.The general behaviour showed that the activity was almost certainlydue to a gaseous compound, and not to the mechanical carryingover of a spray of the liquid. Its rate of spontaneous decomp~si-tion was investigated. A t the ordinary temperature in an atmo-sphere of hydrogen, 20 per cent. remained undecomposed afterfifty minutes, but at3 higher temperature dissociation proceededmuch more rapidly. Only 6 to 7 per cent. remained on passingthrough a tube heated to 350O. If the tube was heated to rednessa t one point, complete decomposition occurred with the sharpdeposition of thorium4 just beyond the heated portion, exactlyas in Marsh’s test for antimony.The gas could be condensed byliquid air, and, by the use of strong preparations, it was possiblet o establish that a small fraction revolat*ilised when the liquid airwas removed. It is hoped that the experience gained as to tbebest conditions for its formation will lead to its beconling possibleto put into evidence the formation of ordinary bismuth hydrideby chemical or rnicrochemical methods.45 The research isanalogous to that previously reported on a volatile hydride ofpolonium .46A170~nencZat.z~re of the Rndio-eZeme~zts.-But for the war, thenomenclature of the radio-elements would have been discussed atthe International Congress, proposed to be held in Vienna in 1916.I n the meantime, a nomenclature has been provisioiially adoptedby the German and Austrian investigators, and used in the treatiseon radioactivity by Meyer and von Schweidler.47 As regards thesynibols, isotopes are indicated by Roman, successive products byArabic indices, thus: GI, UII ; MsTh,, MsTh,; UX,, UX,; thename uranium-P is retained f o r the branch product.a t the headof the actinium series, but f o r the branch products of theC-members, one dash indicates the isotopes of polonium and twodashes the isotopes of thallium. Thus we have ThC”, RaC’’, AcC’,indicating the members usually so designated, but ThC”, RaG”’,and AcCIf for what are usually known as Th-D, Ra-C,, and Ac-D.Radium-D retains its present significance, but the names thorium-U45 F.Paneth, Zeitsch. EEektrochem., 1918, 24, 298 ; further details have been46 Ann. Report, 1916, 266.47 S. Meyer and E. von Schweidler, Zeitsch. Elektrochem., 1918, %, 36;REP -VOI,. xv. 1published too late for inclusion here (Ber., 1918, 51, 1704, 1728).*4., ii, 94 ; compare K. Fajans, ibid., 1917, 23, 250 ; A., 1917, ii, 523226 ANNUAL REPORTS ON THE PROGRESS OF CHEMIYTKT.and actinium-l) are given to the products, respectively, ofactinium4"' (the main product) and of t-horium-C' in the majorbranch. Fajans, on the other hand, somewhat. earlier, proposedmeantime retaining the names first given by t.he discoverers, andthis is khe plan adopted for the most part in the accompanyingfigure . 46.Vat ural Radioactiuity.Radioactivity of the ,4 tnzosphere.-The height in the atmosphereto which t-he various radioactive gases and their products may beexpected to extend has been the subject of inquiry.Owing to thedecay of the radio,active substance which is supplied from the soil,its quantity will decrease with the height from the surface of theearth the more rapidly the shorter is its period of average life.The heights in which the quantities may be expected to be reducedto one-half of the value a t the surface are: for the radium emana-tion and its short-lived products, 1200 metres; for thorium-B andits short-lived products, 100 to 150 metres; for actinium-B andproducts, 10 to 20 metres; f o r thorium emanation and thorium-A,2 to 3 metres; and for actinium emanation and actinium-A, 0.5 to1 metre.The distribution of radium-D and products should beessentially uniform up to a height of 10 kilometres. So far asexperimental evidence, from balloon ascents, is available for thecase of the radium emanation, the calculated distribution withheight appears to be borne out. On this basis, the total quantityof radium emanation in the whole atmosphere is calculated to beabout 2 x 107 curies, o r the quantity in equilibrium with some20 tons of radium (element).49A study of the quantity of the radium emanation in the atmo-sphere a t Freiburg, Switzerland, extending over several years, gavefor the mean content 131, with a maximum of 305 and a minimumof 54 ( x 10-18 curie per c.c.), which is solmewhat higher than thevalues previously found in other localities.As elsewhere, thequantity was found to vary in a more or less regular manner withthe meteorological conditions.60Radioactivity of Rocks.-A radioactive survey of the Archwncomplex of Mysore State, S. India,sl affords an interesting example4 8 Compare also C. Schmidt, Zeitsch. anmg. Chem., 1918, 103, 116 ; A.,ii, 305.49 V. F. Hess and W. Schmidt, Physikal. Zeitsch., 1918, 19, 109 ; 9.,ii, 213.J. Olujih, Jahrb. Radioaktiw. Elektronik, 1918, 15, 158 ; d., ii, 420.W. F. Smeeth and H. E. Watson, Phil. Mug., 1918, [vi], 35, 206 ; A . ,ii, 96RADIOACTIVJTP. 227of the independent evidence afforded to the petrologist by radio-activity in dealing with the complicated problem of classifying andcorrelating the members of a highly metamorphosed and confusedmass of rocks.The oldest rocks, epidiorites and hornblendicschists of the Dharwar system, are low and uniform in radiumcontent, between 0.14 and 0.25 ( x 10-12 gram per gram), and thenext in age, the rocks of the Chloritic series, do not much differfrom them. The intrusions of the Champion gneiss and the relatedquartz veins o€ the Kholar field contain much more radium, whilstthe basic intrusions of Dharwar age contain much less radium thanthe schists themselves. The next oldest rocks, t.he Championgneiss, Peninsular gneiss, and elmepet granite, contain some fourtimes as much radium as the Dharwar schists and some twelve orfifteen times as much as those next following in order of age, theCharnockites, which stand quite apart in their very low radiumcontent, and which Holland had previously classified as a distinct..petrographical province. These very ancient rocks, which are all:presumably of igneous origin, contain, in general, remarkably littleradium, the more basic less than the more acidic, as is usuallyfound, except for the Charnockites, which are of intermediatechemical coniposition. I n the Kolar field, where the schists a10fairly uniform, no increase in radium content occurs with the depthbelow the surface.The examinatlion of a Sardinian porphyritic granite showed thatits radioactivity, which was traced to the presence of uraniferousbiotite, had probably been acquired by the action of percolatingwater that had previously traversed strata containing uraniumA number of other Italian minerals have also beenexamined .53Meteorites.-An investigation of the radioactivity of twenty-two meteorites showed that the metallic meteorites are practicaIlyfree from radium, and that the stony meteorites contain, thoaverage, less than one-fourth of ths radium contained in anaverage granite.64Radioactivity of Natural Waters.-A detailed and prolongedexamination has been made into the radioactivity of the naturalwaters of a very small area in the NeuchBtel Jura mountains, with-out disclosing any inter-eonnexion between the radioactivity, whichin all cases was small, and the volume of flow, temperature,62 A. Serra, Gazzettta, 1917, 47, ii, 1 ; A., ii, 348.53 L. Francesconi, N. Granat,a., A. Nieddu, and G. Angelino, ibid.,I 4 T. T. Quirke and I,. Finkelstoin, dmer. J . Sci., 1917, [iv], 44, 2374, i, 112 ; A., ii, 421.1917, ii, 576.I 2and1918,; A.‘328 ANNUBL REPORTS ON THE PROGltESS OF CHEMISTRY.chemical composition of the springs.55 There were a few thermaland mineralised springs in the region examined, but they were notspecially radioactive. The radioactivity of the springs increasedin passing across the Jura chain in the direction from S.E. t oN.W., and, travelling in this direction, the crystalline rocksbeneath come nearer to the surface.Several investigations have been niade of the radioactivity ofbhe waters in the Philippine Islands. The ssa-water from ManilaBay, in the China Sea, was found t o contain a quantity of radium,from 0.2 to 0-1 ( x gram of radium per litre), much lowerthan has been found for sea-water from other parts of the world.66The waters of some ninety springs in the Philippine Islands con-t’ained radium emanation frm 21 t o 13 ( x curie per litre),but no dissolved radium.57 I n the mountainous region of northernLuzon, which shows evidence of recent< vulcanism, and where saltand hot springs are numerous, no highly radioactive waters wereencountered.58 One spring was examined over long periods oft,ime, during which great variations in the volume of flow tookplace, but the emanation content. of the water remained remark-ably constant.FREDERICK SODDY.tj5 H. Perret and A. Jaquerod, Arch. Sci. phys. nut., 1915, [iv], 45, 277;66 J. R. Wright and G. W. Heise, Philippine J. Sci., 1918, 13, [A], 49 ; A . ,57 Idem, J . Physical Chem., 1917, 21, 535 ; A., 1917, ii, 560.58 G. W. Heise, Philippltte J . Sci., 1917, 12, [A], 293, 309 ; A., ii, 182.366, 418 ; A., ii, 255.ii, 420

ISSN:0365-6217    

DOI:10.1039/AR9181500195

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

INDEX OF AU’I’HORS;’ NAMES,lckroyd, H., 155.-Adam, R., 56, 70.Agcaoili, F., 127.Agrestini, A, 131.diyer, 9. R. P., 185.X i , B., 182.Allen, H. S., 2.Alway, F. J., 184.Amberger, C., 193.Ames, J. W., 181.Anderson, R’. P., 121.-lndrews, J. C., 13.Angelino, G., 227.Anslow, G. A, 219.Applebey, RI. P., 136.Arkuszewski. Z., 78.Armsby, H. P., 192.Arndt, hf., 4.-4ronberg, L., 5, 205.Aten, A. H. W., 26.Auffenberg, E., 58.duwers, K. von, 58, 95, 99.Baar, *4., 57.Bailey, C. H., 192.Baker, J. C., 139, 193.Balareff, D., 34, 123, 124.Bamberger, E., 95.Bancroft, W. D., 18.Barkla, C. G., aO8, 210.Barnes, J. H., 182.Bau, A., 128.Baudisch, O . , 79. 126. 187.Eaumann, L., 115, 155.Bayliss, W. M., 145, 146.Bear, 5’. E., 179, 183.Reckmann, E., 27.Behrman, A.S., 141.Bell, H., 219.Remry, E., 101.Benedicks, C., 209.Bennett, H. S., 23.Berczeller, L., 64, 141,Eerginaiin, X., 66, 78.Bernthsen, W,, 85.Bevan, E. J., 69.Eichowsky, F. R. von, 24.Bigelow, S. L., 17.Bilhuber, E. A., 82.Eloor, W. R., 163.Blouilt, B.. 118, 122.Bodforss, S., 84, 85.Boesekeii, J., 55. 56, 71.Bottcher, B., 115.Bolam, T. R., 24.Booge, J. E., 13.Bougault, J., 126.Bousfield. W. R., 15.Brandt, L., 135,Brandting, K., 164.Brange, E.. 123.Braun, J. von, 78. 80, 94, 102, 110Braun, V., 123.Brenchley, (Miss) W. E., 190.Bridgman, J. A., 140.Briggs, T. R., 23.Brighton T. B., 24.Brill, R.’C., 127.Brooks, B. T., 49.Brooks, S. C., 190.Brovn, H. T., 185.BruBre, P., 38.Bruhns, G., 136.Cuckley, J.P., jun., 128, 193.Buckmaster, G. A., 147.Rurd, J. S., 174.Burns, D.. 153.Burrows, G. H., 119.Carnot, &4., 137.Centnerszw-er, 51,. 18.Cha.mot, E. M., 130.Chapman, A. C., 92, 160, 170.Chaudun, (MIle.) 9., 17.Chauvenet, E., 38.Chemische Werlre Grenzack. 82. 11:230 IXDE X OF L4UTHORS ’ NAMESChernoff, L. H., 64, 188.Christie, A. W., 178.Ciamician, G., 190.Clarens, J., 124.Clark, A. B., 132.IClark, A. H., 165.Clarke, G., 161, 188.Cleage, D. A,, 94.Clogne, R., 163.Clough, G. W., 61.Clouston, D., 185.Coffmann, W. B., 192.Cohen, J. B., 63.Cole, H. I., 130.Coleman, D. A., 182.Colin, H., 17, 129, 186, 187.Collenburg 0. O., 43.Comanducci, E., 126.Combes, R., 189.Compton, A.H.. 24.Cook, F. C., 191.Cope, W. C., 118.Coupin, H., 191.Cowie, G. A., 180, 185.Crabtree, H. G., 104.Cranston, J. A., 196.Cretcher, L. H., jun., 49.,Crookes, (Sir) W., 6.Cross, C. F., 69.Crowell, R. D., 127.Csonka. F. A.. 120.Cunningham, (Miss) BE., 64, 67, 68, 183.Curtius, T:. 72.Curtman, L. J., 126, 131.Dale, H. H., 151.Dale, J. K., 63.Dalmas, D., 132.Darapsky, A., 72.Davis, H. S., 121.Davis, RI. D.. 121.Davisson, B. S.. 124.Dean, R. S., 133.Debye, P. 3, 207.Deichsel, b., 8.Demoussy, E., 191.Denhm, H. G., 40.Denham, W. S . , 69.Denigh, G., 127, 131.Dennis, L. M., 140.DhBr6, C., 170.Dieckmann, W., 57.Dienerc, F , EM.Dimroth, O., 93.Djenab, K., 164.Doherty, E. H., 192.Donnellv, J. L., 42.Dorfmiiller, G., 159.Drathen, E.von, 41.Drew, H. D. K., 61.Dreyfus, H., 52Drummond, H., 145.Drummond, J. C., 72.Dubrisay, R., 121.Dunnicliff, H. B., 33.Dziewonski, K., 88.Eck, P. Pj. van, 142.Edgar, G., 135.Edhofel, E., 57.Ehrenberg, P.. 175.Eichel, A., 109, 110.Ellis, M. T., 188.Elmer, W., 50.Embden, G., 163.Emery, W. O., 130.Engelder, C. J., 51.Ent, L. A. vaii der, 56.Escaich, 142.Euler, H., 164.Everest, A. E.. 187.Ewing, P. IT., 192.Farbkr, E., 164, 194.Pajans, K., 201, 225.f‘aville, K. E., 56.Fearon, W. R., 125.Feigl, J., 149.Fellenberg, T. von, 127, 189.Fernau, A., 222.Feulgen, R., 65, 160.Field; A. J., 128.Fiessinger, N., 163.Finkelstein, L., 227.Finks, A. J.. 188.Fischer, E., 65, 66, 78.Fischer, H.L., 127.Fleming, 149.Fleming, F. L., 192.Follett, H. L., 129.Pormanek, G., 129.Fortini, V., 128.Praiwesconi, L., 227.Francis, F., 132.French, H. E.. 56.Freudenberg, K., 107.Freudenheirn, M. E., 53.Friedemann, 0.. 93.Fries, J. A., 192.Fry, H. S., 42.Fryer, P. J., 128.Fuchs, w., 75.Fulmer, H. L., 183.Funchess, M. J., 190.Furman, M. H., 137, 140.Gainer, P. L., 181.Garola., C. V., 123.Gaudion, G., 51, 52.Gedroitz. K. K.. 175.Georgeacopol, E:, 80,, 88.Ghosh, J. C., 11INDEX OF AUTHORS' NAMES 231Gibson, R. B., 171.Gilbert, C. A., 18.Gill, A. H., 188.Qillespie, L. J., 176.Gillet, R., 189.Glattfeld, J. W. E., 63, 64.Godlewska, M., 83.Godon, F. de, 70.Gorcke, M., 4.Goetkch, G., 71.Gooch, F.A., 135, 138, 140.Gortner, R. A., 192.Gramont, A. de, 119.Granata, N., 227.Gray, T., 139.Greathouse, L. H., 139.Green, A. G., 74.Grey, E. C., 194.Grist, W. R., 94.Growhuff, E., 41.Grossfeld, J., 123, 129, 137.Grossmann, H., 137.Griittner, Gerha.rd, 95. 96.Gruttner, Gertrud, 96.Gueylard, (Mlle.) H., 38.Gurjar, A. M., 192.Raar, A. W. van der, 68.Hager, G., 178.Hahn, O., 197.Hale, W. J., 185.Hallberg, G., 164.Hamburger, L., 5, 22.Hammareten, 0.. 188.Hanke, M. T., 64.Hanson, S., 146.Hantzsch, A., 7, 8, 54, 55.Harden, A., 167.Hardtke, O., 5.Hardy, W. B., 144.Harkins, W. D., 5, 205.Harned, H. S., 140.Harpster, W. C., 122.Harris, B. R., 126.Hart, E. B., 193.Hartmann, W., 74.Hartwell. B. L., 177.Harvey, E.N., 171.Harvey, T. F., 130.Harwood, H. E., 139.Hawkins, E. M., 123.Haworth, W. N., 67.Hedenburg, 0. F., 63.Heidenhain, H., 124.Heider. K., 94.Hein, F., 9.Heise, G. W., 228.Heller, G., 104.Hemsalech, G. A., 6.Henderson, G. H., 216.Henderson, L. M., 220.Henderson, P. S., 153.Herzenberg, J., 80.Herzfeld, 129.Herzog, A., 120.Hess, K., 107, 109, 110, 112.Hess, V. F., 226.Hevesy, G. von, 14.Hickinbottom, W. J., 93.Higgins, W. F., 221.Hills, T. L., 182.Hiltner, R. S., 129.Hines, H. M., 155.Hcmgland, D. R., 173, 176.Honigschmid, 0.) 201.Hofmann, K. A., 122.Hofmann, O., 72.Hole, R. S., 183.Holland, E. B.. 128, 193.Holmes, A., 202.Holmes, (Miss) Ill. C. C., 34Holtsmark, J., 5.Hopkins, F.G., 155.Howard, A., 183. 184.Howard, G. L. C., 184.Howden, R., 133.Howell, J. T., 219.Hudson, C. S., 63, 64.Hunecke, H., 101.Huff, W. J., 134.Humphrey, G. C., 193.Humphrey, I., 49.Huntly. G. N., 122, 123.Hurwitz, S. H., 148.Hutchinson, H. B., 180, 18.3.Ibbotson, F.: 135.Iles, L. E., 118.Illingworth, C. B.. 139.Tnguddsen, T., 115.Ishino, M., 214.Itiano, A., 182.Jacoby, M., 194.Jaeger, F. M., 24.Janicke, J., 44.Jakobsen, A.. 181.Jander, G.. 23.Jannasch, P., 139.Jaquerod, 9.. 228.Jaquet, D., 73.Jensen, C. A., 181.Jodidi, S. L., 130.Jnreensen, L., 190.Jorlander, H., 84.Johansson, D., 164.Johns, C. O., 188.Joly, J.. 223.Jones, H. M.. 115.Jones, T. G. H., 77.Bones. W., 158, 159232 IXDEX OF AUTHORS' HAMESKailan, A, 50.Kalshoven, H., 55.Kamm, O., 7U.Karaoglanow, Z., 138.Karrer, P., 46.Rnserer, H., 132.Katz, bf.H., 121.Kauffmann, H., 82.Kaufman, C., 131.Kaufmanii, A., 74, 113.Kawase. S., 187.Kelber, C.. 29, 74.Kelley, G. L.. 139.Kelling, G., 132.Kemp, A. R., 135.Kendall, E. C., 170.Keiidall. J.. 13.Keyes, D. B.. 24.Kidd, F., 190.Kiiiiura, M., 7.Kindler, M., 113.Kirchhof, F., 22.Klaus, B., 79.Kleinschmidt, A, 39.Klernenc, d., 57.Kline, M. A., 184.Knight, G. W., 129.Knuclsen, L., 190.Kiiudson, A, 163.Kobayashi, 31.. 135.Kober, P. -4.. 120.Kohler, Z., 75, 102.Kohlrausch, K. W. F., 211.Kohlweiler, E., 206.Kolthoff, I. M.. 22, 125, 136.Rcmatsu, Y.. 69.Kond6, K . , 189.Konek, F. von, 42.Kornfeld, G., 175.Korten, E., 87.Krause, E., 95, 96.Rritzmanrn, L., 107.Kroll, w., 35.Kroo, J., 3.Kruyt, H.R., 22, 23.Kiister, W., 116.IJaChS, M.. m, 223.Laing, (Miss) M. E.. 25.Laird C. N., 140.Lal, S., 33.Lampe. V., 83.Lane. K. IT., 136.Langhans. A, 126.Liaquer. F., 163.La.ubi, O., 139.Lebedev, A, 166.Lee, R. E.. 18.LQger, E., 114.Leibbrandt. F., 107.Leichtlin, H., 93.LeistP, R . , 139.Leitch, (Miss) G. C., 67.Leme. 9. B. P.. 119.IJena,it. 129. 'Levene, P. A., 49, 157, 158, 159, 162,169.Levite, -4., 164, 194.Lewis, A., 126.Lewis, G. N., 24.Lewis, W. C. M., 19.Ley, H., 133.Lidstone, F. N., 119.Liesche, O., 27.LiQvin, O., 129.Lifschitz, I., 107.Lifschiitz, I., 163.Lincoln, C. T., 129.Lind, S.C., 218.Lindt, 136.Lipschitz. W., 66, 78.Lmmis, A. G., 219.L6pez-Su$rez, J., 169.Lubs, H. S., 132.Liidere, H., 10%.McBain, J. W., 24.McCoy, H. N., 220.McCrudden, F. H., 123.McDole, G. R., 184.MacGregor, D. G., 121.Maclean, H., 161.IIcLean, H. C., 181.McQuarrie, I., 146.Maggi, H., 69.Mailhe, A., 70, 71.Mannheim, J., 137.Blaquenne, L.. 191.Marck, I. L. B. van der, 118.Marini, C., 187.Martin, G. H., 61.Martin, J. C., 178.Mason, W., 20, 49,Mathews, J. H., 56.Maue, G., 125.Rlauthner, F., 82.Mayer, F., 103.Rleauris, V. L., 142.Meighan, J. S., 152.hfeitner, L., 197, 220.Meldrum, R., 141.Merck, K., 85.Meyer, K. F., 148.BJeyer, R., 102.Meyer. S., 225.Meyerhof, O., 168.Milbauer, J., 47.Miller, C.F., 179, 191.Miller, E. C., 192.Milner, S. R. .. 11.Milobeiidzki, T., 51, 52.Mintz, M., 80.Miyake, K., 180.Modrakowski, G., 149INDEX OF AUTHORS’ NAMESMoir, J., 133.Moller, L., 155.,Monhaupt, M., 141.,Moore, B., 146.Moore, F. J., 105.Morgan, G. T., 94.Moser, L., 134.&fuller, E., 58, 82, 94, 110.Xuller, H., 74.Muller, W., 99.Jfunim, O., 101.Nadratowska, 31. , 204.Nagai, N., 83.Nakasako, R., 157.Name, R. G . van, 134.Nef, J. U., 63.Xeidle, M., 30, 176.Neuberg, C., 164, 166, 167, 194.Newbery, E., 9.Nicholson, J. W., 4, 211.Nicolle, (Mlle.) L., 38.Nieddu, A, 227.Xiggemaiin. H., 8, 9.Nordlund, I., 30.Norton, R. P., 192.Noth, H., 65.Yoyes, H. A . , 177.Ohlon, S. E., 6.Ohlsen, H., 164.Oluji6, J., 226.Orator, V., 149.Orr, B., 156.Osborne, T.B., 193.Oshima, R., 189.Osterhout, W. J. V., 186, 190, 191.Osugi, S., 177.Oven, L. W. H. van, 191.P a l , c., 74.Palet, L. P. J., 131.Paneth, F., 225.Parker, C. E., 129.Partington, J . R., 16.Paterson, C. C., 221.Paul, R., 27.Pauli, W., 222.Papman, VC’., 20, 49.Peck, E. B., 41.Pember, F. R., 177.Pennington, (Miss) H. S. de, 63.Perkin, W. H., jun., 112.Perret, H., 228.Pfeiffer, P., 81.Piccard, A.. 199.Pickerinq, S. U., 175.Pictet, A., 69.Pierson, H. L., 23.Platzmann, C . , 27.Plunimer. J. K., 177, 183.Pollak, J., 57.Polkcoff (Miss). F.. 77.Porter, A. W.. 15, 17.Potter, Itt. S., 182.Prager, S., 127.Prinz, TT., 134.Pyman, F. L.. 114.Quirk, T.T., 227.Rabe, P.. 113.Rae, W. N., 31.Randall, M., 24.Rather, J. B., 124, 189.Rathsburg, R.. 50.Ratner, S., 217.Rau, M. G., 75, 77.Ravenna, C., 190.Ray, G. B., 182.Read, R. E., 158, 159.Reilly, J., 93.Reinders, W., 22.Reinfurth, E., 166. 194.Rhead, T. F. E., 21.Rice, F. E., 177.Richards, H. N., 151.Richards, T. W., 203.Richmond. T. E., 181.Roberts, E.. 193.Robinsoii, C. S., 17.Robinson, (Mrs.) (2. hl., 93, 97.Robinson, R., 77, 93, 97, 104.Robinson, R. H., 34.Robinson, IT’. O., 119, 191.Rosenheim, A., 23, 44.Roseiimund, K. Mi., 52, 73. 74.Rothmund, V., 175.Rule, A., 32.Rule, H. G., 71.Rupp. E., 134.Russell, E. J., 178.Ruth, E. G., 171.Rutherford, (Sir) E.. 215.Ruzifika, L., 91.Sabatier, P., 51, 52.Sachnowski. X., 51.Sahni, R.R.. 224.Salm, E., 127.Salmon. s. C., 192.Sarasin; J., 69.Sargent, C. S., 123.Schaarschmidt. L4., 80, 87, 88.Schaefer, K . , 9, 9: ‘Schellenberg, -4.. 74.Schibsted, H., 122.Schlundt, H., 219.Schmidt, C . , 206, 226.Schmidt. IT., %6234 INDEX OF AUTHORS’ NAMESSchneider, L., 136.Schneider, W., 66.Schollkopf, K., 59.Scholl, R., 87.Schryver, S. B., 161, 188.Schudel, G., 129.Schumb, W. C., 203.Schwarz, A., 74.Schwejdler, E. von, 225.Schwenk, E., 164, 194.Scott, W., 140.Sebastian, R. L., 24.Seibert, 3’. M., 122.Seidenberg, A., 128.Sen, J. N., 183.Senter, G.. 61.Sepp, J., 66.Serra, A., 227.Sharp, L. T., 176, 185.Shaw, R. H., 192.Shedd, 0. &I., 181.Shippy, B. A., 119.Shive, J.W., 191.Siegbahn, M., 204.Simonsen, J. L., 75, 76, 77, 86.Slator, A., 193.Slawinski, I<., 54.Slylte, L. L. van, 139. 193.Smeeth, W. F., 226.Smith, A, 184.Smith, C. L. A., 148.Smith, E., 148.Smith, F. H., 192.Sneed, M. C., 137.Snyder, R. S., 182.Soddy, F., 196, 199, 203.Soderman, M. A., 138.Sorensen, S. P. L., 144.Somieski, C., 36.Sommer, H. XI., 193.Sommerfeld, A., 3.Sonn, A., 74, 100.Sparks, C. F., 130.Spencer, G. C., 130.Spencer, M. G., 139.Spurway, C. H., 124, 177.Stanford, E. E., 188.Stang-Lund, F., 31.Stark, J., 4.Steel, T., 123.Steele, (Miss) E. S., 65.Steenbork. H., 188.Stein, B., 103.Steinkoenig. I,. A.. 191.Stenstrijm. W., 204.Stewart, A. W., 3, 205.Stewart, G. R., 173.Stiehler, 0..66.Stiles, W., 190.Still, C. J., 62.Stock, A,, 36.Stoklasa, J., 193.Stoll, -4.. 186.Sturm, W., 71.Suknarowski, S. , 88.Svanberg, O., 164.Szego, E., 64.Szwejkowska, M., 52.Tarugi, N., 135.Taussig, L., 148.Taylor, E. S., 145.Thannhauser, S. J., 159.Thaysen, A. C., 183.Thiele. J., 85.Thomas, J. S., 32.Thomas, R. M., 105.‘Thompson, (Sir) W. H., 143, 153, 154.Thuras, A. L., 140.Tingle, A., 119.Tinker, F., 16.Todd, G. W., 17.Traube, W., 41.Travers, A., 135, 138, 139.Tsakalotos, D. E., 132.Tschugaev, L. A., 47, 131.Tsiropinas, F., 127.Tsujimoto, M., 92, 170.Tucker, S. H., 61.Tutton, A. E. H., 42.Ukita, K., 50.Underwood, J. E., 218.Vakil, K. H., 74.Vegard, L., 3, 206.Vegezzi, G., 170.Venable, C. S., 105.Vibrans, F. C., 185.Viehover, A., 188.Voelcker, J. A., 191.Vortmann, G., 123, 131.VotoEek, E., 136.Wagner, 141.Wmakeman, A. .J., 193.Wallnch, O., 89, 90.Walsh, J. W. T., 221.Walter, B., 220.Walters, E. H.. 179.Washburn, E. W., 10.Watanabe, C. K., 153.JQatson, A. M., 153.Watson. H. E., 226.Waynick. D. D., 185.Weibel. E. E., 140.TiT’eilancl, H. J.. 10.Weinhagen, A. B., 108.Wenger, P., 123.Werner, A, 46, 60.Werner, E. A., 70.Werner, L. F., 112INDEX TO AUTHORS’ NAMESWertemtein, L., 204.West, C. J., 162.Weatan, F. E., 128.Wheeler, R. V., 20, 49.Wherry, E. T., 119.White, (Miss) 11. P., 208, 210.Whitternore, C. F., 218.Widman, O . , 89, 100.Willaman, J. J., 120.Willard, H. H., 139.Willsktter, R., 73, 129, 186.WiLson, J. B., 191.Windaus, A., 125.WinMer, L. W., 138.Winterstein, E., 108.Wintgen, R.. 36.Wirth, W. V., 56.Wise, L. E., 176.Wislicenus, H., 186.Wislicenus, W., 59, 82.Witzemann. E. J., 53.Wober, R., 130.Wohler, L., 31.Woker, G., 69.Wolkoff, M. I., 191.Wolter, L., 126.Wood, R. m7., 7.Woodburn, (Miss) H., 69.Woodward, T. E., 192.Wrede, F., 67.Wren, H., 62.Wright, A., 149.Wright, A. H.. 127.?Vright, J. li., 228.Wiiest, H. M., 85.Yanovsky, E.. 119.Yoder, L., 177.Zetzsche, F.. 52, 73, 74.Zinke, A.? 87

ISSN:0365-6217    

DOI:10.1039/AR9181500229

出版商:RSC    

年代:1918

数据来源: RSC

摘要:

IXDEX SUBJECTSAcenaphtheiie, dehydrogenation of, 88.Scetaldehyde, 52.Acetic acid, separation of, 127.-4cetone, 53.5- and 6-Acetylaniino-3 : 4-dimethoxy-benzoic acids, nitration of, 75.*~lcetylaminoveratric acids, bromination4-_~cetylaniiiio~~eratrole, nitration of,Acetylaminoveratroles, bromination of,Acetylcarbinol, detection of, 126.,V - Acetyl- o - hydroxylaininobenzalde-Acidity of soil, 176.Acidosis i n shock, 149.,4cids, aliphatic, and their derivatives,Scridine, synthesis of, 102.Actinium, parent of, 195.Actinouranium, 199.Acyl groups, migration of, 77.Adrenaline, synthesis of, 83.Agricultural analysis, 122.Alcohols, aliphatic. arid their deriv-*4ldehgdes, preparation of, 73.Alizarin, oxidation of, 87.Alkali metals, polyhaloid salts *of the,Alkaline reserve of the body, 146, 150.-4lkalinity, estimation of, 132.Alkaloids, of the areca nut, 107.cinchona, 113.of the cocaine woup, 112.ipscacuanha, 1104.of the pomegranate tree, 109.estimation of, 128.of, 77.75.77.hyde, 95.54.atives, 50.aliphatic, 52.detection of.125.31.Allotropy. 26.Amidine salts, 71.Amines, bromoalkyla ted aromatic, 94.Amino-acids, 72.A4mmonia, estimation of, 124.Ammonium polyhaloid salts, 31.Analysis, agricultural, 122.tertiary aromatic, steric hindrancein, 78.estimation of, 130.electrochemical, 139.gas, 121.inorganic, 130.organic, 125.physical, 118.Anhydrides, organic, preparation of,56.Anils, 95.Anisotropy, 22.Anthocyanins, production of, in plants,Aiithraquiiioiies, 86.L4ntimoi~y , metallic, 41.Areca nuti alkaloids of, 107.Arecaidine, 108.Arecaine, 108.drginine, 153.Arsenic compounds, 45, 46.Atom, constitution of the, 206.Atomic numbers, 1.,itmosphcre, radioactivitv of the, 226.Bacteria in soil, 182.Barium, estimation of, 138.Bases, cyclic, relative stability o f , 102.Benzanthrone, 87.Benzidine transformation, theory of, 97.Renzoic acid and p-hydroxp-, in soil,Benzoylglucose, 65.Rerberine group, the, 112.l?ismuth hydride, 224.187.structure, 2.179.23INDEX OF SUBJECTS 23';%lood, carbon dioxide in, 143.Body, alkaline reserve of the, 146, 150.Boric acid, detection of.130.Boron and its compounds, 35.a'soBrazilein, 103.Bromic acid, estimation of, 134.Bromine, estimation of, 136.Brucine.estimation of, 129.Butaldehyde, 52.Butyric acid, estimation and separationof, 127.proteiila of the, 148.Cadmium. detectioit of, 131.Calcium arsenates, 34.estimation of, 136.Carbohydrates, 63.Carbohydrate metabolism, 163.Carbon dioxide in blood, 143.Carnosine, synthesis of, 115.Carnotite, extraction of radium from,Carotin, occurrence of, in seeds, 188.Catalysis, 18, 70, 73.Cells, living, phosphoric acid complexesCellulose, structure of, 68, 69.Chemical dynamics, 17.Chlorene, 88.Chlorine, estimation of, 135, 136.Chloroform, preparation of, 50.Chondroitin-sulphuric acid, 169,Chromium compounds, 42.estimation of, 138.Chronioisomerism, 81, 106.Cinchona alkaloids, 113.C i t r d , estimation of, 128.Cobalt compounds, 46.Cobaltammines, optical activity of, 60Cocaine, 110.Colloids, 21, 29.emulsoid, 143.effect of radium rays on, 222.Colour and constitution, 81.of animal skin, 171.Compounds occurring in nature, synthesis of, 82.Conhydrine, 109.Copper, basic carbonates of, 33.detection of, 130.estimation of, 133, 136.Gourn aranone, d z l y droxy -, 100.Coumarin group, the, 99.Creatine, 153.Creatinine, 153.Cryptoisomerism, 81.Curcumin, synthesis of, 83.Cyanamide as a fertiliser, 185.Cyanogen, estimation of, 136.assimilation of, by plants, 185.219.of, 157.elements, genesis, nature, and reln-tions between the, 205.Dehydrogenation, 88.Dextrose, biochemical degradation of,estimation of, 129.Diazo-compounds, mechanism of coup-Diazoimines, 93.Dicyanodiamide as a fertiliser, 185.Diethylamine, preparation of, 70.Digallic acid, 77.Dimethylglyoxime, preparation of, 70.Dimethyl-o-toluidine, reactions of, 78.Disaccharides, 66.Disinfection, 18.165.ling of, 92.use of, in analysis, 137.Eccaine, 111.Ekatantalum, 195.Electrical conductivity of solutions, 9.Electrochemical analysis, 139.Electrolytes, strong, abnormality of, 11.Electro-osmometer , 23.Elements, chemioal, genesis, nature andElemicin, synthesis of, 82.Ismetine, 114.Emulsoid colloids.143.Ergotinine, detection of, 126.Esters, aliphatic, 56.isomerism of, 57.Ethylamine, preparation of. 70.Ethylene oxides, 84.relations between the, 205.Fats, meta.bolism of, 163.analysis of, 128.Feeding stuffs, 192.Fermentation, 193.Ferric oxide, hydrated, colloidal soln-tions of.30.Fertilisers, 185.Flames, 21.Flooculation in soil, 175.Fluorescence of organic compounds, 82.Fluorine, estimation of, 135.Formic acid, detection of, 125.estimation of, 127.Gas analysis, 121.Gaseous mixtures, ignition of, 20.inflammability of, 20.Gluccsides. 66.Guaiacol, detection of, 125.5-nitro-. nitration of. 77.Guanidiire compounds, biochemistry of.151.Hzmin, 116.Hanoglobin, 147.Halos, pleochroic, 223.Helicorubin, 170.cycloHexanone. derivative6 of, d9.Hexosephosphoric acid, 164, 194.Histidine, preparation of, 115238 IDDEX OF SUBJECTSHydsocarbow, aliphatic, 48.polycyclic aromatic, 85.Hydrochloric acid, estimation of, 132.Hydrocyanic acid, detection of, 125.Hydrocyclic compounds, 89.Hydrofluoric acid, use of, in analysis,Hypobromous acid, estimation of, 134.H ypoiodous acid, estimation of, 134.Ignition of gaseous mixtures, 20.Iminohydrins, constitution of, 71.Iminovioluric acid, 107.Pndenes, 85.Indole derivatives, theory of formatioilInflammability of gaseous mixtures, 20.Inorganic analysis, 130.compounds in plants, 190.Inositolphosphoric acids, esAmation of,Insects, luminescence of, 171.Intramolecular changes, theory of, 97.Iodic acid, estimation of, 134.Iodine, resonance spectra of, 7.Iodometry, 133.Ions, nature of, 13.Ionisation, 9.Ipecacuanha alkaloids, 114.Iron, spectra of, 6.estimation of, 133, 135.Irrigation of soil, 183.Isatin group, the, 104.Isobares, 206.Isotopes, spectra, of, 5.halogen derivatives, 50.137, 14.0.of, 98.124.detection of, 130.estimation of, 134.solubility of salts of, 203.of lead and uranium, 201.Kephalin, 161.Ketones, aliphatic, 52.Lactose, canstitution of, 67.Lzvulose, estimation of, 129.Lead, isotope of, 201.spectra of, 204.sub-salts of, 40.sulphide, estimation of, 133.organic compounds, 95.estimation of, 136, 141.Lecithin, 161.Lipoidase, 163.Liquids, surface energy o f , 24.Luminescence of insects, 171.2 : 6-Lutidine, preparation of, 101.Magnesium phosphates, 34.estimation 'of, 138, 141.Nalonic acid, detection of, 126.Jfanganese, estimation of, 139.Mercury, colloidal solutions of, 30.ammonium compounds, 34.fulminate, detection of, 126.estimation of, 136.Mesityl oxide, action of hypuchlorousMesothorium, lif e-period of, 2%).Metals.sepaxation of, 137, 138.Meteorites, radioactivity of, 227.2 - Methoxy-m-tolualdehyde, nitrationMethyl dcohol. estimation of, 127.sulphate, use of, for methylation, 56.Slethyl-B-bromoethyl'aniline, 94.Methglfructoside. 65.acid on, 54.the milligram of, 219.spectra of, 5.of, 76.Methylpentoses, detection of, 125.Milk, 193.Molybdenum compounds, 44.estimation of, 135, 139.Norindone, constitution of, 86.Mucoitin-sulphuric acid, 169.Mucosin, 169.P-Naphthylamine, sulphonation of, 74,Nebulium, atomic weight of, Wl.Nephelometry, 120.Nickel, colloidal solutione of, 29.detection of, 131.Nitriles, catalytic preparation of, 70.Nitrogen, assimilation of, by plants,187.compounds, aliphatic, 69.aromatic, 92.estimation of, 126.estimation of, 134.Sitrous acid, detection of, 142.Somenclature of radio-elements, 2%.Nucleic acids, 157.Nucleotides, 158.Oenocyanin, 187.Oils, analysis of, 128.Optical activity, 59, 62.Organic analysis, 125.Orientation of organic compounds, 75-Osmium compounds, 47.detection of, 131.Osmotic pressure, 15.Oxalic acid, estimation of, 140.separation of, 12%.2-Particles, scattering of, by gases, 224-Pelletierine, 109.Phenol, estimation of, 129.Phenylsuccinic acid series, racemisa-Phosphatides, 161.Phosahoric acid, detection of, 131.225.methods of analysis, 119, 12%.tion in the, 62.estimation of, 123.complexes of living cells, 157INDEX OF SUBJECTS 239Phosphorus acids, estimation of, 134,142.compounds, 42, 45.in wheat, 189.Physical analysis, 118.Phitosterols of wheat, 188.f'lant growth, 185.Plants, inorganic compounds in, 190.l'loochroic halos, 223.Polypeptides, estimation of, 130.Polysaccharides, 66.Pomegranate tree, alkaloids of the, 109,Potassamide, 31.Potassium chloroaminosulphonate, 41.permanganate, titration of, 135.polysulphides, 32.estimation of, 122.Potential, contact, measurement of, 24eycZoPropane, derivatives of, 89.Propionic acid, separation of, 127.Proteins, 144.of the blood, 148.Protoactinium, 197.Purine group, the, 105.Pyridine Lases, estimation of, 1x1.group, the, 101.Pyridinepolycarboxylic acids, synthesi!O f ) 101.Quantum theory, 19.Quinine group, the, 113.Racemisation, 62.X-Radiations, J - and Z-series of, 210.Radioactive a eposi t s , 21 6.Radioactivity, of meteorites, 227.natural, 226.of rocks, 226.of water, 227.Radio-elements, nomenclature of, 206,R,adiothorium, life-period of, 220.Radium, extraction of, from carnotite,series spectrum of, 219.rays of.effect of, on colloids, 222.y-rays of, 211.sulphate, solubility of, 218,Radium-zinc sulphide paint, decay ofluminosity of, 221.S-Bay spectra, 206.y-Rays of radium, 211.Reaction velocity, 19.Reduction, catalytic, 73.Itesin, estimation of, in soap, 128.Ricinine, constitution of, 115.Rocks, radioactivity of, 226.Selenic acid, estimation of, 134.Selenious acid, estimation of, 133.Selenium compounds, 42.225.table of, 200.219.detection of, 131.Semidine traiisformation, theory of, 97Shock, chemical factors in, 149.Silanes.36.Silicon hydrides, 36.organic compounds, 95.Siloxanes, 36.Silver, estimation of, 136.Soap solutions, constitution of, 24.Sodamide, 31.Sodium polysulphides, 32.Soil, acidity of, 176.chemistry of, 172.Solids, structure of, 24.Solutions, electrical conductiL itp of, 9Spectra, absorption, 7.emission, 4.fluorescence, 6.high frequency, 2.resonance, 7.X-ray, 206.Spectroscopic analysis, 119.Spectrum, series, of radium, 219.Spinacene, 92, 170.Squalene, 170.Steel, analysis of, 135.Steric hindrance, 78.Stizolobin, 188.3trontinm, estimation of, 138.Sucrase, mode of action of, 17.3ucrose, inversion of, 17.5ugars, acetylated, 63.oxida.tion of, 64.estimation of, 129.Y-Sugars, 64.julphites, estimation of, 133.iulphofication in soil, 181.3ulphur.allotropy of, 26.3ulphuric acid. detection of. 131.estimation of manganese in, 139.estimation of, 137.Tantalum, estimation of, 138.hrtaric acid, detection of, 126.I'erpenes, 89.retany, 151.I'&raphenylpyrrole, synthesis of, 98.rheobromine, estimation of, 130.I'hioisotrehalose, 67.rhorium, life-period of, 220detection of, 131.estimation of, 135.I'hymolsulphophthalein, use of, as :tljindica.tor, 132.Thymus gland, iodine camponnd inthe, 170.Thymus-nucleic acid, 160.rin mmpounds, 39.organic. 95.Tissues, constituents of, 169.I'oxicity in plants, 189.rlopic acid, synthesis of, 58, 82.rropiiie gronp, the, 111240l'uiipteii compounds, 43.estimation of, 139.INDEX O F SUBJECTSCranium, atomic weightTJranium I and 11, 2Q4.Uric acid, oxidation of, 105.isotope of, 201.Vanadium, estimation of, 135, 138, 140,141.Velocity of reaction, 19.Violanin, 187.Viscosity, determination of, 118.Wagner rearrangement, the, 90.Walden inversion, 61.Water, natural, radioactivity of, 227.analysis, 141.Yeast, fermentation by, 166,Yeast-nucleic acid, 157.growth of, 193.Zinc, estiniation of, 132.Zirconium compounds, 38.detection of, 131.PRINTED IN GBEAT BRITAIN BY R. CLIP AND .8ONS, I.lD.,BRUNSWICX STREET, STAMFORD STREET, S.E. 1, I??D BUNGAT, SUFFOLH

ISSN:0365-6217    

DOI:10.1039/AR9181500236

出版商:RSC    

年代:1918

数据来源: RSC