摘要:

ANNUAL REPORTSOh’ THEPROGRESS OF CHEMISTRYANNUAL REPORTSON THEPROGRESS OF CHEMISTRYF O R 1904.ISSUED 3Y THE CHEMICAL SOCIETY.8r,ommitfar o f @ubIicirtiair :H. T. BROWN, LLD., F.R.S. H. MCLEOD, F.R.S.A. W. CROSSLEY, D.Sc., Ph.D. E. J. MILLS, D.Sc., LL.D., F.R.S.WYNDHAM R. DUNSTAN, M.A., LL.D., Sir W. RAMSAY, K.C.B., LL.D., F.R.S.A. SCOTT, D.Sc., F.K.S.M. 0. FORSTER, D.Sc., Ph.D. W. A. TILDEN, D.Sc., P.R.S.P. F. FRANKLAND, LL.D., F.R.S. W. P. WYNNE, D.Sc., F.R.S.F. R. S.@.'bitox :G. T. MORGAN, D.Sc.Sub-Qbiox :A. J. GREENAWAY.aarrtribufm :P. PHILLIPS BEDBGN, M.A., D.Sc.A. C. CHAPMAN, F.I.C.J. B. COIIEN, Ph.D.H. J. H. FENTON, M.A., F.R.S.W. D. HALLIBURTON, M.D., F.R.S.A. HUTCRINSON, M.A., Ph.D.W. J. POPE, F.R.S., F.I.C.F. SODDY, M.A.J.A. VOELCKER, M.A., Ph.D.J. WALKER, D.Sc., F.R.S.VOl. I.LONDONGURNEY & JACKSON, 10, PATERNOSTER ROW.1905RICHARD CLAY ANn SOKS, rJIMITBD,RREAn ST.-BILL, E.C., ANDBIXGAY, RIJFFOLKINTRODUCTION.THE issue of a systematic series of reports in English on the progressof chemistry in its several divisions and applications has long beendesirable, but a definite scheme was not formulated until April last,when the Council of the Chemical Society adopted a resolution thatsuch reports should be prepared for the year 1904, and continuedannually. The division of the subject under the same headings asthose adopted for the classification of the Abstracts published inthe Chemical Society’s Journal was thought convenient, but the largeextent of matter to be dealt with made i t necessary further to dividethe work of reporting on the department comprised under the title of‘( Organic Chemistry,” while it was thought probable that in futureyears a similar subdivision of ‘( General and Physical Chemistry ”mould become necessary.An additional article referring to thehistory and development of the new subject of ‘( Radioactivity ”has also been prepared.The object of these ‘LReports” is to present an epitome of theprincipal definite steps in advance which have been accomplished in thepreceding year, for the benefit of all workers, students, or teachers ofchemistry, or those chemists who are engaged in technical or manufactur-ing applications of chemistry, in order that specialists in any one depart-ment of the science may obtain without difficulty information as tothe nature and extent of progress in other branches of the subject towhich they have not paid special attention.With these objects in view, the Council invited a number of gentle-men, distinguished for their acquaintance with the several divisionsof the subject already indicated, to prepare Reports, and their namesattached to the several articles afford a guarantee that the work hasbeen done carefully, judiciously, and accurately.Obviously, the selection of matter from so large it field involves theapparent neglect of some subjects, but it is believed that in the severaVi INTRODUCTION.Reports nothing has been omitted which can be regarded as of funda-inerital importance.It must further be added that inasmuch as no Report can be finishedby the author before December 31st in each year, and in a few casesit will necessarily be somewhat later, the Reports cannot be i l l thehands of the Fellows of the Society till the early Spring, though it isto be hoped that they may be ready some time before the AnniversaryMeeting.W.A. TCONTENTS.PAGEGENERAL AND PHYSICAL CHEMISTRY. By JAMES WALKER, D.Sc.,Ph.D., F.R.S. . . . . . . . . . . 1INORGANIC CHEMISTRY. By P. PHILLIPS BEDSON, M.A., D.Sc. . 30ORGANIC CHEMISTRY -ALIPHATIC DIVISION. By H. J. H. FENTON,M.A., P.R.S. . . . . . . . . . . 55By JULIUS B. COHEN, Ph.D. . . . . . . . . 84STEREOCHEMISTRY. By WILLIAM JACKSON POPE, F.R.S., F.I.C.. 132ANALYTICAL CHEMISTRY. By ALFRED CHASTON CHAPMAN, F.I.C. , 148PHYSIOLOGJCAL CHEMISTRY.M.D., B.Sc., F.R.C.P., F.R.S. . . . . . . . . 169ORGANIC CHEMISTRY-AROMATIC AND OTHER CYCLIC DIVISIONS.By WILLIAM DOBINSON HALLIGUR'I'ON,AGKICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY.By JOHN AUGUSTUS VOELCKEX, &LA., Ph.D., B.Sc., F.I.C. . . 192RADIOACTIVITY. By FREDERICK SODDY, M.A. . . . . . 244XINERALOGICAL CHEMISTRY. By ARTHUX HU'I'CIIIXSON, M. A., Ph. D. 22TABLE OF ABBREVIATIONS EMPLOYED IN THEABBREVIATED TITLE.Amar. Chem. J. , . .A ~ Y . J. Pharm. . .Amer. J. Xci. . . ,Analyst . . . .Annalen . . . .Ann. Physik . . .Ann. Agron. . . ,Ann. C?t.int. anal. . .Ann. Chim. Phys. . .Ann. Inst. Pasteur . .Ann. sci. Univ. Jassy .Arch.Hygiene . . .Arch. NLerland. . .Arch. Pharrn. . . .Arch. Xci. phys. nat. ,Atti R. Accd. Sci. Torino .Atti R. Accnd. Lincei .Zeilr. chem. Phy.viol. Path.Ber. . . . . ."Bied. Centr. . . .Bihnng K. Svenska Vet.-Bull. Acad. roy. Belq. .Bull. Acad. Sci. Cracozo .Bull. Coll. Agr. T6kyO' .Bull. Geol. Soc. Amer. .Bull. xoc. Chim,. . .Bull. Xoc. franq. Min. .Bull. Soc. ind. Mulhouse .Centr. Bakt. Par. . .Akad. Hadl.Centr. Min. . . ."Chenz. Centr. . . .Chm. News . . .Chm. Rev. Felt Rc6r3 Ind.Chem. Zeit. . . .REFERENCES.JOIJENAL.American Cheniical Journal.American Journal of Pharmacy.American Journal of Science.The Anslyst.Justus Liebig's Annaleii cler Chemie.Annalen der Physik.Annales agronomiques.Annales de Chimie analytique appliqude h l'Industrie,Annales de Chimie e t de Physique.Annales de 1'Institut Pasteur.Annales scientifiqnes de 1'Wniversite de Jassy.Archiv fiir Hygiene.Archives Nkerlandaises des sciences exactes et natur-Archiv der Pharmazie.Archives des Sciences physiques et naturelles.Atti della Reale Accademia delle Scienze di Torino.Atti della Reale Accademia dei Lincei.Beitrage fiir chemische Physiologie und Pathologie.Berichte der Deutschen chemischen Gesellschaft.Biedermann's Centralblatt fiir Agrikulturchemie undBihang till Kongl. Svenska Vetenskaps-AkademiensAcadhie royale de Belgique-Bulletin de la ClasseBulletin international de l'Acad6mie des Sciences deBulletin of the College of Agriculture, Imperial Uni-Bulletin of the Geological Society of America.Bulletin de la Soci6td chimique de Paris.Bulletin de la Sociktk franpaise de Minbralogie.Bulletin de la Socidtb industrielle de Mulhouse.Centralblatt efiir Bakteriologie, Parasitenkunde nndCentralblatt fiir Minernlogie, Geologie und Palaeon to-Chemisches Centralblatt.Chemical News.Chemische Revue iiber dic Fett- und Harz-Industrie.Chemiker Zeitung.& l'dgricnlture, A la Pharmacie et la Biologie.elles.rationellen Landwirtschafts-Betiieb.Handlingar.des Sciences.Cracovie.versity, TBkyB.Infektionskrankheiten.logie.* Abstracts from the CtdmlLZntt are made only in tlie case of papers published in journalsother than those incliided in this listX TABLE OF ABRREVlATIONS EMPLOYED IN THE REFERENCES.ABBREVIATED TITLE.Compt.rend. . . .Compt. rend. SOC. Biot. .Exper. Stat. Zecord . .Gaxzetta . . . .Geol. Mag. . . . .Jakrb. Min. . . .Jahrb. Min. Beil.-Bd. .J. Aqner. Chcm. Soc. . .J. Fed. Inst. Brewing. .J. Geol. . . . .J. Hygiene. . . .J. Landw. . . . .J. Med. Research . .J. Path. Bact. . . .J. Pharrn. Chim. . .J. Physical Chem. . .J. Physiol. . . . .J. Physique . . .J. pr. Chem. . . .J. Boy. Agric. SOC.J. ~ o y . ~ o c . New ' ~ o u t iJ. Buss. Phys. Chem. Soc. .J. SOC. Chem. Ind. . .Landw. Ycrsuchs-Slat. .L'Orosi . . . .Mem, Accad. Sci. Torino .WalesMem. llfanchester Phil. SOC.Milch Zeit. . . .Min. Mag. . . . .Monatsh. . . . .Mon. Scient. . . .Nwvo Cim.Cfver K. Vet.-kkad.'FiiriPJEiiger's Archiv.. .Phamn. Arch. . . .Pharna. J. . . . .Pharm. Rev. . . .Phil. Mag. . . .Phil. Tram . . .Proc. . . . . .Proc. Anwr. Physiol. SOC. .Proc. Canth. Phil. Soc. .Proc. Phil. Soc. Glnsgow .Proc. Physiol. J'oc. . .Proc. K. Akad. Wetensch.Proc. Roy. SOC. . . .Proc. Roy. SOC. Edin. .Quart. J. Geol. Soc. . .Amsterdam.JOURNAL.l'Acad6mie des Sciences.Comptes rendus hebdomadaires des SOances deComptes rendus des SQances de la Soci6t6 de Biologie.Experiment Station Record.Gazzetta chimica italiana.Geological Magazine.Neues Jahrbuch fiir Mineralogie, Geologie und Pal-aeontologie.Neues Jahrbuch fur Mineralogie, Geologie und Pal-aeontologie. Beilage-Band.Journal of the American Chemical Society.Journal of the Federated Institntes of Brewing.Joizrnal of Geology.Journal of Hygiene.Journal fur Landwirtschaft.Journal of Medical Research.Journal of Pathology and Bacteriology.Journal de Pharmacie et de Chimie.Journal of Physical Chemistry.Journal of Physiology.Journal de Physique.Joiirnnl fur praktische Chemie.Journal of the Royal Agricultural Society.Journal of the Royal Society of New South Wales.Journal of the Physical and Chemical Society ofJournal of the Society of Chemical IndustryDie landwirtschaftlichen Versuchs-Stationen.L'Orosi.Memorie della Reale Accademin delle Scienze diTorino.Memoirs and Proceedings of the Manchester Literaryand Philosophical Society.Milch Zeitung.Mineralogical Magazine and Journal of the Mineral-ogical Sock ty.Monatshefte fur Chemie nnd verwandte Theile andererWissenschaften.Moniteur Scientifique.I1 Nuovo Cimento.Ofversigt af Kongl.Vetenskaps-Akademiens Fiirhand.lingar.Archiv fur die gesammte Physiologie des Menschenund der Thiere.Pharmaceutical Archives.Pharmaceutical Journal.Pharmaceutical Review.Philosophical'Magazine (The London, Edinburgh andPhilosophical Transactions of the Royal Society ofProceedings of the Chemical Society.Proceedings of the American Physiological Society.Proceedings of the Cambridge Philosophical Society.Proceedings of the Glasgow Philosophical Society.Proceedings of the Physiological Society.Koninklijke Akademie van Wetenschappen te Anister-dam. Proceedings (English Version).Proceedings of the Royal Society.Proceedings of the Royal Society of Edinburgh.Quarterly Journal of the Geological Society.Russia.Dublin).LondonTABLE OF ABBREVIATIONS EMPLOYED IN THE REFERENCES.xiABBREVIATED TITLE.Rev. intarn. Fat$. . .Rec. trav. chim. . . .Sci. Proc. Roy. Dubl. Soc.Xei. Tram. Eoy. Dzcbl. Sac.Sitzungsber. K. Akad. WisS.Sitxungsber. K. A k d Mun-Trans. . . . .Trans. A m r . Inst. MiningTrans. Nova Scotin Inst.Trans. Path. SOC. . .Trans. Roy. Xoc. Cunada .Trans. Roy. Irish Acad. .Tsch. Min. illitth. . .U.S.A. Dept. Agric. Bull. .U.S. A. Dept. Agric. Eep. .Wiss. Abhandl. Phys. - Z'cch.Zeit anal. Chem. . .Zeit. angew. Chem . .Zeit. anorg. Chew. . .Zeit. Biol. . . . .Zeit. Elektrochem. . .Zeit.Farb. Text. Ind. .Zeit. Kryst. Min. . .Zeit. Nahr. Genussrn. .Berlin.C h e l z .Eng.Sci.Reichsnnstalt.Zeit. ofentl. Ohm. . .Zeit. physikal. Chem. . .Zeit. physiol. Chern. . .Zeit. prakt. Gcol. , .Zeit. Ver. dezct. Zuckerind.Zeit. Zuckerind. Biihm. .JOURNAL.Revue intcrnationale des Falsifications.Receuil des travanx chimiques des Pays-Bas et de laScientific Proceedings of the Royal Dublin Society.Scientific Transactions of the Royal Dublin Society.Sitznngsberichte der Koniglich Preassischen Akademieder Wissenschaften zu Berlin.Sitzungsberichte der koniglich bayerischen Akademieder Wissenschaften in Munchen.Transactions of the Chemical Society.Transactions of the American Institute of MiningTransactions of the Nova Scotia Institute of Science.Transactious of the Pathological Society.Transactions of the Royal Society of Canada.Transactions of the Royal Irish Academy.Tschermak's Mineralogische Mittheilungen.Ridletins of the Department of Agricultme, U.S. A.Reports of the Department of Agriculture, U.S.A.Wissenschaftliche Abhandlungen der Physikalisch-Technischen R eichsanstalt.Zeitschrift fur analytische Chemie.Zeitschrift fiir angewandte Chemie.Zeitschrift fiir anorganische Chemie.Zeitschrift fiir Biologie.Zeitschrift fiir Elektrochemie.Zeitschrift fiir Farben- und Textil-Industrie.Zeitschrift fiir Krystallographie und Mineralogie.Zeitschrift fur Untersuchung der Nahrungs- undZeitschrift fur ijffentliche Chemie.Zeitschrift fur physikalische Chemie, Stiichionietrieund Verwandtschaftslehre.Woppe-Seyler's Zeitschrift fur physiologische Chemie.Zeitschrift fiir praktische Geologie.Zeitschrift des Vereins der deutschen Zucker- Industrie.Zeitschrift fiir Zuckerindustrie in Biihmen.Belgique.Engineers.Genussmittel

ISSN:0365-6217    

DOI:10.1039/AR90401FP001

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

INORGANIC CHEMISTRY.REVIEWING the past year naturally calls to mind the fact that duringits course many have passed away whose energies have been directedto the advancement of our knowledge of the elements and their com-pounds, and who have busied themselves with establishing soundtheoretical explanations of the facts of the science of chemistry.Notably amongst these stands the name of Alexander W. Williamson,whose death on May Sth, a t the ripe age of eighty, ended the career of%L man the history of whose services to science takes us back to thosetimes when chemistry was striving for clear views of the fundamentalconceptions of “ atom ” and ‘( molecule.” I n this country, Williamson’sinfluence for the benefit of science has not been confined t o hiswritings and teaching alone, but is also to be seen in the services heperformed in the administration of the affairs of societies concernedwith the advancement of science.On July 23rd died C. A. Lobry deBruyn, for a short period prior to his death Professor of Chemistry a tthe University at Amsterdam, whose investigations cover a wide fieldand represent all branches of chemistry, and to whom we are indebtedfor the isolation of pure hydroxylamine and of pure hydrazine.Professor Clemens Winkler died on October 8th, at the age ofsixty-six ; for many years he was associated in various capacities withthe School of Mines at, Freiberg, and throughout his life remained aconstant and devoted worker in the department of inorganic chemistry.Winkler did much to develop and simplify the methods of volumetricand gas analysis, and by his devices has made the latter capable ofeveryday application in technical work.His researches made clearthe requirements for the successful manufacture of anhydrosulphuricacid.The discovery of germanium will always be reckoned amongst thegreat achievements of Winkler ; the properties of this element suppliedthe third confirmation of the prediction by Mendeldeff of the propertiesof the elements required to fill the spaces in the system of elementsarranged in the order of their atomic weights, and such confirmationhas undoubtedly influenced the minds of chemists in their acceptanceof the Periodic Law. MendelEeff has recently demonstrated the elasINORGANIC CHEMISTRY.31ticity of this system in his speculations on the composition of theether, set forth in the work translated by G. Kamensky, entitled‘ I An attempt towards a Chemical Conception of the ether.”To the groups in the periodic system, in the first place, Mendeleeffproposes to add a zero group in front of group I. I n this zero groupare placed those elements, helium, neon, argon, krypton, and xenon,with the isolation and properties of which the researches of Sir W.Ramsay and his pupils have made us familiar; a group of elementscharacterised by their chemical inactivity, for which, therefore, valenceis reduced to zero, and further, substances whose molecules aremonatomic. Helium belongs to the second series commencing withlithium and ending with fluorine, whilst the first series is repre-sented only by hydrogen, a homologue of lithium, that is, belongingto the same group.The element in the first series of the zero group isrepresented by “ y,” a substance which must have the properties charac-teristic of the argon gases. It is calculated from the relation of theatomic weights of the elements in the neighbouring group that thiselement has an atomic weight of less than 0.4. The relative densityof ‘( y’) in relation t o hydrogen would be 0.2, and it may be identifiedwith the substance coronium,” whose spectrum mas first observedby Young and Harkness in the corona during the eclipse of 1869.Nasini, Anderlini, and Salvadori considered that they had found tracesof coronium in their examination of the spectra of volcanic gases(1 893).The molecules of ‘( y ” would not be sufficiently light, nor would theirvelocity be great enough, to identify this element with ether.To com-plete the series of elements, therefore, a zero series is added, and inthis series in the zero group is placed an element c r ~ , 7 7 which Men-clel6eff regards “ (1) as the lightest of all the elements, both in densityand atomic weight ; (2) as the most mobile gas ; (3) as the elementleast prone to enter into combination with other atoms, and (4) as anall permeating and penetrating substance.” This element ‘( x,” it issuggested, is the ether, the particles and atoms of which are “ capableof moving freely everywhere throughout the universe, and have anatomic weight nearly one-millionth that of hydrogen, and travel witha velocity of about 2,250 kilometres per second.”AS Mendelkeff points out, “ the conception of the ether originatesexclusively from the study of phenomena and the need of reducingthem t o simpler conceptions.Amongst such conceptions we held for along time the conception of imponderable substances (such as phlo-giston, luminous matter, the substance of the positive and negativeelectricity, heat, &c.), but gradually this has disappeared, and now wecan say with certainty that the luminiferous ether, if it be real, isponderable, although it cannot be weighed, just as air cannot b32 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.weighed in air, or water in water. We cannot exclude the ether fromany space; it is everywhere and penetrates everything, owing to itsextreme lightness and the rapidity of motion of its molecules.There-fore such conceptions as that of the ether remain abstract, or concep-tions of the intellect, like the one which also leads us to the veryteaching about a limited number of chemical elements out of whichall substances in nature are composed.”Ths future will decide whether these ideas are destined t o take aplace among the accepted interpretations of natural phenomena ; butthe history of the reception of the first suggestions from which the‘6 periodic law ” has grown warns us against too dogmatic an attitude.The record of the work in inorganic chemistry during tho year1904 gives evidence of great activity on the part of those chemistswho cultivate this special department of research ; whilst, possibly,the discoveries may be lacking in the sensational nature of those whichhave characterised the two previous years, still there is a rich store ofmaterial, containing much that gives precision to our knowledge ofelements and compounds where such exact information has beenwanting.The very nature of this material and its varied character,which of necessity arises from the number of the elements and theirnumerous compounds, makes the writing of a Report of this kinda matter of considerable difficulty, and necessitates the selection ofresearches which can be dealt with from a few general points ofview.Thus, for example, we may take in the first place some of theresults which have accrued from the investigations carried out underconditions which the ready command of low temperatures has madepossible.The study of the compounds formed by liquid halogenhydrides and organic substances, such as acetone and ether, byArchibald and McIntosh,l offers an instance of this kind. Thecomposition of these compounds is shown to find a simple explanationin the increased valency of oxygen at low temperatnres. Thus thecompound (C2H5),0,HI, it is suggested, may be regarded as contain-ing a quadrivalent oxygen atom, thus : C2H5>O<F, rather than asimple additive compound ; similarly, (CH,),CO,HBr is represented ascH3>C:O<Fr. Whilst these and other similar substances indicatethe influence of temperature on the valence of oxygen, the further in-vestigations of such substances may realise in compounds such asC2H5CH3CH H3>O<Br, H and CH3>O<gC13 the asymmetry of the oxygen6 5 (32%atom.1 Trans., 1904, 85, 919INORGANIC CHEMISTRY.33Stock and Guttmann,l in their researches on antimony hydride, haveavailed themselves of liquid air to liquefy and solidify this gas, whichis best prepared by the action of hydrochloric acid upon an alloy ofmagnesium and antimony containing 33 per cent. of the last-namedmetal. Exact determinations of the physical constants of thiscompound have been made, its solubility in many solvents noted :whilst it is readily soluble in ether, ligroin, and benzene, these solu-tions quickly become turbid ; carbon disulphide is essentially thesdvent for this gas, dissolving 250 times its own volume.It is readilydecomposed by electric discharge, and at times decomposes spon-taneously into antimony and hydrogen. The dry gas is stable, thepresence of moisture promotes its instability, and it is attacked by theair at the ordinary temperature. It reacts readily with oxygen formingantiniony and water, and converts nitric oxide into nitrous oxide,nitrogen, and ammonia, antimony being formed a t the same time.The halogens decompose it readily. By the action of air or oxygenon the liquid at - go", an unstable yellow modification of antimony isformed, which dissolves in carbon disulphide, forming an intenselyyellow solution. At - 50", this form passes into the metallic varietyof antimony.By vaporising arsenic in a vacuum and condensing the vapoiirs byliquid air, the quantitative conversion into yellow arsenic has beeneffected by Stock and SieberL2Francesconi and Sciacca 3 have studied the interaction of liquidnitric oxide and liquid oxygen, obtaining in this way nitrogen trioxide,which is also formed by gaseous nitric oxide and oxygen a t - 110" ;the conversion of nitrogen peroxide into nitrogen trioxide by nitricoxide takes place at - 150". The trioxide is stable nncler theordinary pressure at -21".W i t t ~ r f , ~ in the investigation of themelting points of mixtures of nitrogen peroxide ant1 nitric oxide,obtained a blue liqiiicl of the composition N,O,, which solidifies toa blue solid melting at - 103"; with increase in proportion ofnitrogen peroxide, the melting point falls to the eutectic point of- 112".By treating sulphur chloride with liquid chlorine in sealed tnbes,Ruff 5 has shown sulphur tetrachloride to be formed as a solidmelting between - 30.5" and - 31" ; the liquid formed readily decom-poses-in fact, a few degrees above the melting point its dissociationpressure exceeds one atmosphere.A number of compounds of sulphurtetrachloride and chlorides of other elements are described, as also acompound with arsenic fluoride.Rer., 1904, 37, 885.Gazzettcb, 1904, 34, [i], 447.BcT., 1904, 37, 4513.Ibicl., 4572.Zeit. nnorg. Chem., 1904, 41, 85.VOL. I. 34 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.From the cryoscopic study of the solution of chlorine in arsenictrichloride, Smith and Hora1 conclude that the pentachloride is notformed as previously stated by Baskerville and Bennett.Amongst other facts brought to light in researches at low temperaturesare the demonstration of the fact that solid hydrogen is a crystallineand not a viscous solid,2 the absorption of nitrogen by liquid oxygendescribed by Erdmann,s and the selective absorption for oxygenpossessed by charcoal a t very low temperatures affording, as Dewar 4shows, a means of separating oxygen from nitrogen.Utilising theabsorption of hydrogen by charcoal in vessels cooled by liquid bydro-gen, Dewar has obtained vacua of so high an order that an electricdischarge does not take place in the tube.From experiments madewith helium in the same way cooled to 15' on the absolute scale, avacuum is obtained in which the electric discharge produced only anintermittent phosphorescence ; from his experiments, Dewar concludesthat helium boils at about 6' absolute.To Dewar 5 we are indebted for the determination of the densitiesof solid oxygen, nitrogen, and hydrogen, from which the molecularvolumeB of these elements at absolute zero have been calculated to be21.21, 25.49, and 24.18 respectively. The latent heat of vaporisationof liquid oxygen and liquid nitrogen has been ascertained by A h 6Many instances of the application of electricity in the isolation ofelements are recorded ; especially noteworthy is the manufacture ofmetallic calcium by the electrolysis of fused calcium chloride, thedevice adopted by Messrs.Suter and Redlich, of Bitterfeld, obviatingmany of the difficulties surrounding this mode of producing theelement. An iron cathode, so arranged that it can be slowly raised,dips on to the surface of the molten chloride, and when the metalhas been formed round the end of the rod it is slightly withdrawn, sowhilst still maintaining connection gives rise to the gradual productionof a rod of the metal calcium. Some of the more important physicalconstants of this metal, purified by distillation, have been ascertainedby Arndt,7 who notes the energetic action of the metal on air, yieldingcalcium oxide and nitride (Ca,N,).The electrolytic decomposition of solid caustic soda at temperaturesnear its fusing point is recorded by Haber and Tolloczko,s who alsohave similarly decomposed barium chloride at about 400' below itsJ. Anzer.Chem. Soc., 1904, 26, 632.'2 Travers (Proc. Roy. Soc., 1904, 73, 151).3 (Bey., 1904, 37, 1193) ; Erdmann and Bedford (Ber., 1904, 37, 1184)..I Compt. rend., 1904, 139, 261 and 421.(i Ann. Physik, 1904, [iv], 13, 1010.8 Zcit. ano?-g. Chem., 1904, 41, 407.Proc. Roy. Soc., 1904, 73, 251.Ber., 1904, 37, 4733INORGANIC CHEMISTRY. 35melting point, and have noted that when barium carbonate is added tothe chloride, carbon is observed to separate at the cathode. Further,when barium chloride is electrolysed in a current of carbon dioxideand air, the following reaction takes place :BaCl, + CO, + 0 = BaCO, + Cl,.Calcium and sodium chlorides are each decomposed in a similarmanner.Coehn and Kettembeill have found it possible to separate, in theform of an amalgam, barium from strontium, barium from calcium,and strontium from calcium by electrolysing solutions of the mixedchlorides, using a mercury cathode and varying potentials.Coehn2 shows that whilst radium is not deposited from solutions ofits compounds in alcohol, acetone, or pyridine on a platinum cathode,it is deposited from its aqueous solutions on a mercury cathode, andthis, when treated with hydrobromic acid, gives a permanently activebromide. Whereas the electrolytic separation of the alkaline earthsis possible by using mercury cathodes, it is not possible to separateradium from barium save by working with currents of extremelylow current density.Metallic radium is precipitated from its saltsolutions by barium amalgam. I n this connection, mention shouldalso be made of Marckwald’s proposal to separate radium by treatingsolutions of radium barium chlorides with sodium amalgam.Muthmann and Weiss have obtained the metals of the cerium group 4by the electrolysis of the anhydrous chlorides, in some instances alone, inothers by admixture with barium chloride. The metals were purifiedby fusion in crucibles made of pure magnesia, and covered with alayer of barium chloride ; the action of lanthanum, neodymium, andpraseodymium on silicates excludes the use of ordinary crucibles.Samarium is not readily obtained from its fused chloride, but has beenproduced by the electrolysis of a mixture of the chloride and bariumchloride.I n each case the cathode consisted of a small rod of carbon,and the current employed varied from 50-100 amperes. I n the caseof samarium, a layer of carbide is formed round the cathode, on whichthe metal is subsequently deposited. The metals have been obtainedin quantities sufficient to establish definitely their physical appearanceand constants, such as the specific gravities and their melting points.The latter constants were ascertained by heating the metals inmagnesia crucibles under a layer of potassium and sodium chlorides,the liquefaction being indicated by the movement of a weighted rod ofmagnesia resting on the surface of the metal, the values found forthe specific gravities being as follows : cerium, ‘7.0424 ; lanthanuin,Zcit. nnorg.Chcrn., 1904, 38, 198.Ibid., 88.A’(?., 1904, 37, 811.Annnlen, 1904, 331, 1.0 36 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.6.1545 ; neodymium, 6.9563 ; praseodymium, 6.4'764 ; samarium,7*7-7*8 ; whilst the melting points were found to be for cerium 623O,lanthanum 81 0", neodymium 840°, and praseodymium 940".These metals can all be burnt in the air, and the heats of combustionhave been determined, giving in each case high values. The specificgravities afford an opportunity of deciding the position to which theseelements may be assigned in the curve of atomic volumes and atomicweights, and support Benedick's suggestion that these rare earths shouldoccupy a position on the descending curve between barium and tantalum.Alloys of cerium with aluminium, with magnesium, and with zinc,as also an alloy of lanthanum ancl aluminium, have been prepared byMuthmann and Beck.2 These alloys combine with hydrogen a t200-400", forming hydrides of cerium and lanthanum. The ceriummagnesium alloy a t 900' reacts with nitrogen forming the nitrides ofthese elements.Cerium forms a liquid, and also a solid amalgam withmercury, both of which readily decompose water with the evolutionof hydrogen. Neodymium hydride, NdH,( 0 ),, and praseodymiumhydricle, PrH,(?), as also the nitrides NdN and PrN, have been formedby the direct union of the elements.3By utilising the isomorphism of the double salt, bismuth magnesiumnitrate with the corresponding double salts of magnesium nitrate a dnitrates of the rare earths, Urbain and Lacombe4 have succeeded inisolating a pure europium sulphate, the amount obtained representing2 parts per 100,000 parts of monazite sand.It is a rose-colouredcrystalline solid, having the composition Eli2( S0,),,8H20, and yieldsthe oxide as a rose-colonred powder; the atomic weight assigned to theelement is 151.79. These authors have also obtained pure samariumoxide, ancl give to this element the atomic weight 150-34.5Nitrobenzene-m-sulphonic acid has been found by Holiberg 6 toforin salts with neodymium, praseodymium, and lanthanum, thefractional crystallisation of which permits of the production of pureneodymium compounds,R.J. Meyer 7 describes a series of complex double carbonates of thecerium earths and of the alkali metals ; the potassium cerium carbonatehas the composition K,Ce,(CO3),,12H,O, which may be taken as atype ; these potassium compounds are readily soluble in aqueoussolutions of potassium carbonate, and are precipitated from this solutionon adding water in the following order : lanthanum, praseodymium,cerium, and neodymium. By the aid of these compounds, lanthanumcan be completely separated from cerium and didymium.Zeit. anorg. Chcm., 1904, 39, 41. Anwnlen, 1904, 331, 46.]bid., 58. Comnpt. rend., 1904, 138, 84. ' Ibid., 1166.Pihang. K. Svenska. Vet.-Akad.-Handl., 1902-1903, 28, ii, No.5 , 1.7 Zeit. anorg. C'hem., 1904, 41, 97INORGANIC CHEMISTRY. 37That neodymium can be freed from lanthanum by the fractional pre-cipitation of the chlorides by hydrogen chloride has been proved byBaskerville and Stevenson,l who also satisfied themselves of the unityof the neodymium chloride so purified. Baskerville's attempts toprepare alums from the sulphates of lanthanum, praseodymium, andneodymium with those of rubidium and cerium have, while failingto yield alums resulted in the isolation of several double salts. By theaction of concentrated sulphuric acid on cerium dioxide, the compoundCe(SO,),, containing quadrivalent cerium, is formecl,3 which, if over-heated, or if water is present in the sulphuric acid, decomposes withthe evolution of oxygen and of ozone and the production of the ceroso-eerie sulphate, HCle'11Ce1V(S04)4, 13H,O.The stability and solubihtyrelations of the hydrates of ceric sulphates have been examined byKoppel with results differing from those of previous observers. Thesubject of the sulphates of the rare earths is dealt with by Brauner in twopapers? in one of which the production of coniylex sulphuric acicls of theformula M(SO,H),, in which M represents either cerium, lanthanum,praseodymium, neodymium, or samarium, is described. These com-pounds are formed by addition of concentrated mlphuric acidto a solution of the normal sulphate in ice-cold water; under similarconditions, thorium forms the salt ThH,( SO,),. Later, Braunerdescribes a series of salts of the complex cerisulphuric acid, such as[CelV(S0,)4]3, CeI'I + 44H,O, in which tervalent cerium may be replacedby lanthanum, praseodymium, and neodymium ; these compounds areisomorphous with one another, forming mixed crystals.A volumetric method for the ready determination of the atomicweights of the elements of the didymium and yttrium groups has beendevised by Wild which should materially facilitate the identificationof the oxides obtained in separating these rare earths.Cerium sulphide (Ce,S,) formed by the action of gaseous hydrogensulphide on the oxide, hydroxide, sulphate, or carbonate at a red heatis not spontaneously inflammable,; whereas the oxy-sulphide preparedby the action of moist sulphuretted hydrogen is.Mosander's golden-yellow sulphide is shown to be crystallised ferric sulphide.For the purpose of separating thorium from cerium, lanthanum, anddidymium, m-nitrobenzoic acid has been advantageously employed byIYei~h,~ the thorium salt, Th(N0,*C6H,*C0,),, being precipitated quanti-tatively from solutions of the nitrate.When thorium oxide mixed with charcoal is heated in a tube ofJ.Amer. Chenz. Soe., 1904, 26, 54.3 Meyer & Autrecht, Ber., 1904, 37, 140.Zeit. anorg. Chcnt., 1904, 38, 322, and 39, 261.7 Sterba, Ann. Chim. Phys., 1904, [viii], 2, 193.J. Anzer. Chenz. Xoc., 1904, 26, 780.I b i d , , 64.Ibid., 41, 377.6 Ibid., 38, 19138 AXNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.silica in a stream of chlorine and the product separated by differencein volatility of the chlorides into three parts, the first fraction,according to Baskerville,l contains the chloride of berxelium, havingan atomic weight 212, and of which the oxide is slightly radioactive.The second fraction contains the thorium chloride, whilst the third frac-tion is the chloride of a metal having the atomic weight 255.6 and styledcarolinium.The ultra-violet spectrum between A3444 and A401 1 ex-hibits, according to Sir W. Crookes, lines identical with those of thorium.Turning to other rare elements, we find >hat by heating potassiumzirconium fluoride with aluminium in an electric arc furnace,Wedekind has obtained compounds of this metal and aluminium, and bysubstituting magnesium for aluminium the production of a crystallinesubstance containing 94.8 per cent. of zirconium takes place.Theelectrolysis of the fused potassium zirconium fluoride yields amorphouszirconium. The tetraiodide of zirconium (Zr14) is produced whenhydrogen iodide reacts on heated zirconium or its carbide; thesublimate is purified by treatment with benzene. It is a yellow, micro-crystalline solid, which fumes in the air, is attacked vigorously bywater, reacts with alcohol forming ethyl iodide and zirconic acid, andforms additive compounds with ether, ammonia, and propylamine. Theoxy-iodide, ZrO12,8H20, corresponding to the oxychloride and oxy-bromide, is formed by action of water on the iodide or by action ofhydriodic acid on zirconium hydroxide, Zr(OH)4 (Stuhb and Denk).Indium and its compounds have been the subject of investigation byseveral chemists.Thiel gives from the analyses of the chloride a valuefor the atomic weight of 115.08 0.03, whilst from the bromide thevalue 114.81 & 0.07 is deduced ; the metal has been obtained by theelectrolysis of its salt solutions and found to melt a t 155' & 1.Renz 5 states that indium oxide (In,O,) sublimes wit'hout meltingwhen heated in an iridium dish, and distinguishes two varieties of thiscompound, one an amorphous modification soluble in acids and asecond crystalline and insoluble form.I n the department concerned with the revision of the atomic weightsof the elements, many observations of importance are to be recorded.Guye and Mallet6 discuss the experimental results obtained byMorley, and, after applying corrections to these average values, suggestthe following: 0=15.8787, H = l , or H=1.00764, 0=16.Thedensities of sulphur dioxide and of oxygen have been determined bythe application of the method used by Morley for hydrogen, giving the1 J. Amor. C'hem. Sobe., 1904, 26, 922. Zeit. Elsktrochsm., 1904, 10, 331.Ber., 1904, 37, 1135.Ihid., 175 ; Zeit. nnorg. Chem., 1904, 39, 119 ; ibid., 40, 280.Ber., 1904, 37, 2110. Compt. rend., 1904, 138, 1034INORGANIC CHEMISTRY. 39weight of 1 litre of oxygen as 1,4292 grams, error &nc, and of sulphurdioxide as 2.92664 grams with maximum error of &a (Jacquerodand Pintza).’The density of nitrous oxide and the determination of its volumetricand gravimetric composition have been utilised for the purpose offixing the atomic weight of nitrogen, giving the value 14.011(Rayleigh,2 Guye and P i n t ~ a , ~ Jacquerod and B ~ g d a n , ~ Guye andBogdan 5).The revision of the atomic weight of rubidium made by Archibald,Owho experimented with specially prepared chloride and bromide, gives85.487 from the chloride, 85.483 from the bromide, and the means ofboth sets of determinations give 85.485.The question of the atomic weight of beryllium is again revived.By the conversion of beryllium acetylacetonate into the oxide,Parsons finds the value 9*113+_0.0059 (0=16), whilst the sameauthor obtains 9.113 0.0043 from the amount of oxide yielded by thebasic acetate, Be,O(C,H,O,),.Haber and Van Oordt have in-vestigated the influence of different salt solutions on the physicalproperties of beryllium hydroxide, and findg that the basic acetateformed by treatment of the hydroxide with glacial acetic acid issoluble in chloroform, a property which affords a means of separatingi t from the insoluble basic acetates of iron and aluminium.Tanatar lohas suggested that beryllium is a quadrivalent element and that thebasic acetate should be represented by the formulaBe( 0*6,H,O),O,Be( O*C2H,0), ;further, that the atomic weight is 18.2, which, when multipliedinto the specific heat at low temperatures, gives an atomic heat of6-8-7.4. Attempts t o produce beryllium alums containing rubidiumand cerium sulphates have been unsuccessful. Possibly the groundsfor this suggestion of Tanatar may find an explanation in thefacts recorded by Pollok11 in his paper entitled “The Compositionof Beryl.” Employing beryl obtained from Limoges, pure berylliawas prepared ; this was mixed with sugar charcoal heated in a stream ofchlorine and the operation conducted in such a way as to allow of theseparation of the more volatile chlorides from the less volatile.The pro-portion of chlorine in these separate portions gave equivalents differingfrom one another to such an extent as to justify the conclusion that theberyl contains, associated with the beryllium, an element of high atomicCompt. rend., 1904, 139, 129.Conzpt. rend., 1904, 139, 677.Ibid., 138, 1494.J. Amer. Chenz. Soc., 1904, 26, 721.lo J. Rzlss. Phys.Chem. SOC., 1904, 36, 82.3 Proc. Roy. Soc., 1904, 744, 181.ti Trans., 1904, 85, 776.8 Zeit. anorg. Chem., 1904, 40, 465.Ibid., 49.’ Ibid., 38, 377.l1 Trans., 1904, 85, 163040 ANNUAL REPORFS ON THE PROGRESS OF CHEMISTRY.weight; from the quoted results, the atomic weight must be muchhigher than that of beryllium. The author considers that his ex-periments explain the anomalous specific heat observed for beryllium,as the metal used would be likely to contain both elements. In fact,whilst determining the heat of formation of beryllium chloride bydissolution of the metal in hydrochloric acid,l the author obtained“ varying numbers for different samples of metals prepared fromdistinct portions of glucina,” all of which appeared to be perEectlypure. The results of these observations led him to undertake thisexamination into the nature of glucina.Moissan 2 has re-determined the relative density of fluorine, usingaegnault’s method, to test the validity of Brauner’s suggestion thatthe activity of fluorine might be due to th,e presence in it of atomicparticles, which the value 1.26, as opposed to the theoretical 1,316,appeared to justify.The mean of four determinations gives 1.31(air = 1 ) ; which is sufficiently near to make Brauner’s assumptioninadmissible.The value to be assigned to the atomic weight of iodine forms thesubject of two publications, one, by G. P. Baxter,3 in which results aregiven of the determination of the ratios : (1) silver to silver iodide, (2)silver to iodine, (3) silver chloride t o silver iodide.The means of allthese experiments gives the value 126.975 (0 = 16), and incident-ally the value 35.467 for chlorine is confirmed. The second publica-tion is that of Kothner and Aeuer,* who purified the iodine employedby first converting it into ethyl iodide, from which, after purification,hydriodic acid was prepared and converted into silver iodide, thusgiving the value 126.026 (H = 1).By weighing the water produced from the hydrogen evolved in thedissolution of aluminium in hydrogen chloride, the value 27.05 hasbeen found by Kohn-Abrest for the atomic weight of aluminium ;whilst from the weight of oxide formed from the metal 27.09 is obtainedas the atomic weight (H= 1).From the analysis of ferrous bromide made by the action of acurrent of nitrogen and hydrogen bromide on heated metallic iron,BaxterG finds the atomic weight of iron t o be 55*S5 (0 = 16),whilst by the reduction of ferric oxide in hydrogen the value 55.S83is obtained.I n this connection, that is, the determination of the stoichiometricvalues of elements and compounds, may be mentioned the examinationof the question of the vnpour density of hydrazine hydrate by Scott,7Pollok, Trims., 1904, 85, 603.J. Amer.Chent. SOC., 1904, 26, 1577.Coinpt. rend., 1904, 139, 669.Tmiw., 1904, 85, 913.Conbpt. Tend., 1904, 138, 728.Bar., 1904, 37, 2536.Zeit. ni~org. Chem., 1904, 38, 23INORGANIC CHEMlSTRY. 41the results of which afford a complete refutation OF the statements ofCurtius and Schultz (1890). The hydrate (N2H4,H,0) is shown to dis-sociate in a vacuum at looo, the dissociation being complete at 143';under atmospheric pressure at 183O, decomposition into ammonia andnitrogen sets in, and a t still higher temperatures further resolutiontakes place.The nature of the surfaces with which the vapour is incontact exerts an influence on the initial temperature of decompositionand also on the rate of the change.I n reference to atomic weight determinations, the warning of theInternational Commission against the use of glass vessels in investiga-tions of this kind finds a justification in the demonstration by Moissanand Siemens that water heated with silicon in glass vessels is attackedwith the liberation of hydrogen, whereas in platinum or quartz nosuch action is observed.This action arises frcm the alkali dissolvedfrom the glass, which in turn interacts with the silicon, forming asilicate which decomposes into the dioxide and regenerates the alkali forfurther action.An indication of the advance made during the past year in ourknowledge of compounds of the elements may most conveniently bearrived a t by discussing some of these under the headings of the groupsin the periodic system.Id.-A series of double compounds of rubidium and bivalent mer-cury, HgI,,RbI, HgI2,2Rb1, has been described by Grossmann,2 alsothe double thiocyanates, Hg(SCN),,RbSCN andHg( SCN),2 Rb( SCN),, &H,O,together with the cynnothiocyanate, Hg(CN),Kb(SCN), which re-sembles very nearly the analogous pyridine compound,The specific gravities of the halides of lithium have been exactly deter-mined by Baxter.3 The production of sodium oxide by the interactionof the peroxide and the metal has been ~ a t e n t e d .~From the standpoint of the phase rule, Fedotkeff 5 has examined theammonia-soda process, concluding that it is better for solid or dissolvedsalt to be brought into contact with solid ammonium hydrogen carbonatethan to operate as in the Solvay process.1B.-The action of sulphuretted hydrogen on the double cyanides ofcopper and potassium shows that whilst the salts [Cu,(.CN),H,O]K andCu,(CN),K, are attacked, those having the formula Cu2(CN),K, arenot acted upon, and Treadwell and Von Griswald 6 conclude that thisHg( CN),,C,H,N( SCN).Compt.rend., 1904,138, 939.Amer. Chem. J., 1904, 31, 558.Badisdie Anilin- & Soda-Fabrik, D.R.-P. 147933 ; Basler Chem. Fabrik,Zeit.physika1. Chew., 1904, 49, 162.Ber., 1904, 37, 1258.D.R.-P. 145754.ci Zeit. anorg. Chev., 1904, 39, 9242 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.is due to the formation of ions containing more than Cu2(CN),,possibly Cu,(CN), or Cu(CN),. Solutions of copper in potassiumcyanide, examined by the electrical method used in the investigation ofsolutions of complex silver salts by Bodliinder and Eberlein,l are shownto contain chiefly the ions Cu(CN),"', and to a less extent Cu(CN);I2.A series of well-defined complex copper salts has been prepared bytreating ammoniacal solutions of cupric salts with solutions of potass-ium or ammonium salts ; for example, [Cu(NH,),](SCN), is formedwhen potassium thiocyanate is ernpl~yed.~ From experiments on theelectrolytic transport in aqueous solutions of copper chloride, it is con-cluded that such solutions contain cathions of complexes containingwater molecules, such as [CuCl(H,O),], which, with water at lowtemperature, act so as to form [ Cu(H,O),]" + Cl', a reaction reversed athigher temperatures.The action of chloric acid on copper and the production of the basicchlorate of this metal are discussed by Brochet,4 and the properties ofcrystallised copper iodates by Grainger and de Schulten.5Normal silver chromate (Ag,CrO,) is formed from a soluble silversalt and a normal chromate, also by the action of water on silver di-chromate.6 Silver dihydrogen pyrophosphate, Ag,H,P,O7, is producedby the solution of silver pyrophosphate in pyrophosphoric acid andprecipitation by alcohol or ether (Ca~alier).~1IB.-The extension of the research on the action at high tempera-tures of manganese fluoride on calcium chloride, by which crystallinecalcium fluoride and calcium fluorochloride are formed, has yielded undersimilar conditions the fluorides of barium and of strontium, also fluoro-chlorides, fluorobromides, and fluoroiodides of the metals of the alkalineearths.* Examples of the composition of these substances are affordedby the following formulae : BaCl,,BaF, ; BaBr,,BaF, ; BaI,,BaF,.Thestudy of the decomposition of mixtures of calcium carbonate and thecarbonates of the alkali metals by heat at 1000" in vacuo shows thatthe mixed carbonates dissociate less readily than calcium carbonate,that the dissociation pressure is lower than that of calcium carbonateand higher than that of the alkali carbonate at the same temperature.Lebeau has also obtained lime in the crystalline form, and proved thatlithia and lime form isoinorphous mixtures of regular octahedral crys-t a l ~ .~ The production of calcium carbide when a mixture of fusedcalcium fluoride and calcium chloride is electrolysed, using a carbonZeit. anorg. Chenz., 1904, 39, 197.Ber., 1904, 37, 1153.Bull. SOC. chim., 1904, [iii], 31, 287, 290, 293.Compt. rend., 1904, 139, 201.7 Compt. rend., 1904, 139, 284.Ibid., 138, 197 ; Ann.Chim. Phys., 1904, [viii], 1, 337.Compt. rend., 1904, 138, 1496; ibid., 1602.Ibid., 41, 369.Zeit. anorg. CIicm., 1904, 4.1, 68INORGANIC CHEMISTRY. 43cathode, has been observed by Moissan,I who has established the factthat lime is not attacked by carbon a t the temperature of the OXY-hydrogen flame, but as crystals of calcium silicate are formed on thelime, Moissan 2 concludes that silica has a distinct vapour pressure a tthis temperature. The insolubility in water of barium sulphate pra-vents the hydration or hardening of this compound, but the solubilitycan be increased by the addition of solutions of aluminium chloride,ferric chloride, or ammonium nitrate, and Rohland has used these toeffect the hardening of barium sulphate.1IB.-Magnesium hydroxide suspended in water is dissolved bycarbon dioxide, and from the solution alcohol precipitates the coinpoundMgC0,,3H20, the solid in suspension gradually acquiring the samecomp~sition.~ The dissolution of this compound in solutions of potass-ium bicarbonate results in the formation of the compoundXgC10,,KHC0,,4H20.5When the chroniates of potassium or ammonium are added to solutionsof zinc chloride, double chromates are produced, whereas with sodiumchromate the basic compound ZnCr04,3Zn(OH)2 is formedmGhas described the double chroinates of nickel and magnesium withpotassium, rubidium, and cerium of the type M2'ILI"(Cr0,),,6H20,analogous to the magnesium double sulphates.By methods similar to those employed in the study of solutions ofcopper salts, Kunscherts proves that the solutions of zinc salts inpotassium or ammonium oxalates contain in concentrated solutionsions, Zn(C,O,),, and in dilute, Zn(C,O,),.The solutions in causticsoda contain the ions ZnO,, which on hydrolysis form HZnO,' andO H I, whereas the solutions in potassium cyanide contain Zn(CN), andZn(CN),.Riy has obtained mercuric nitrite by the interaction of mercuricchloride and silver nitrite ; when heated a t 100" in, vctcuo, thiscompound breaks up thus :BriggsHg(NO,), = HgO + N,O, ; Hg(NO,), = HgNO, + NO.The hydrolysis of series of normal mercuric salts is proved by Coxt o yield basic salts intermediate between the normal salts and theoxide. The decomposition of mercurous nitrate is more complex thanthat of the mercuric salt; mercuric fluoride forms the oxide andhydrofluoi4c acid.1 Conzpt.rend., 1904, 138, 661 ; Bullier, ihid., 138, 904.Ibid., 138, 243.Chem. Zeit., 1904, 28, 868.Monatsh., 1904, 25, 520.3 Zeit. anorg. Chem., 1904, 41, 337.Zeit. anorg. Chenz., 1904, 40, 146.3 Zeit. anorg. Chem., 1904, 38, 311.Zed. B'lektrochem., 1904, 10, 161.Trmts., 1904, 85, 672.9 Trans., 1904, 85, 52344 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.IITA.-For the prcduction of crystallised boron, Kuhne recom-mends mixing boron trioxide with aluminium turnings and sulphur,the actim to be started by applying a red-hot iron rod to a mixtureof aluminium and sulphur ; from the resultant mass, the aluminiumsulphide is removed by dissolving in hydrochloric acid.Silicon canbe obtained by substituting silica for the boron trioxide.The study of the melting-point curves of mixtures of boron trioxideand the oxides of the alkaline earths indicates the existence of ortho-,meta-, pyro-, and cli-borates of these elements.2 From the in-vestigation of the electrical conductivity of solutions of borax,Grunhut3 concludes that borax is resolved on dissolution in waterinto boric acid and the metaborate; when carbon dioxide is passedinto the cold solution, the metaborate decomposes and sodium hydrogencarbonate is formed ; if boric acid is added to the solution saturatedwith carbon dioxide, some metaborate is reproduced in virtue of massaction.IIIB.-When aluminium fluoride is fused with sodium sulphide, amixture of sodium aluminofluoride and sodium thioaluminate isproduced :2A1,F6 + 6Na,S = A12F6,6NaF + A1,S,,3Na2S.This mixture, when electrolysed in the fused state, yields aluminium,sulphur, and sodium fluoride; the rettctions are expressed as follows :A1,S3,3Na,S = 2A1 + 3s + 3Na,S.AI,F,,GNaF + 3Na,S = 281, + 35 + 12NaF.On these reactions is based the following patented process: first,aluminium fluoride is formed from bauxite by the action of hydro-fluoric acid, the fluoride being freed from iron and titanium bydigestion with alumina.The sulphur produced in the above reactionscan be used for the manufacture of the sulphuric acid required toprepare hydrofluoric acid from the sodium fluoride formed, the sodiumsulphate resulting from this reaction being converted into sodiuinsulphide by heating with coal.*By the action of barium chlorate on aluminium sulphate, the twohydrated aluminium chlorates A1(C103),,9H,0 and Al(ClO,),,GH,Ohave been prepared and their behaviour when heated studied, fromwhich it would appear that when slowly heated a t 100' they decom-pose with explosive violence, yielding chlorine peroxide ; when heatedrapidly, chlorine is formed, and a residue of a basic perchlorate,Al,(C104)6,A1203, left.5D.R.-P.147871.Zcit. physikal. Chem., 1904, 48, 569.Gin, D.R.-P. 148627.Dobrosercloff, J. Russ. PJHJS. Chcnz. SOC., 1904, 36, 468.Gnertler, %.?it. anorg. Cliem., 1904, 40, 337INORGANIC CHEMISTRY. 45Mention should be made of Verneuil’s successful production ofartificial rubies by heating alumina with a blowpipe flame, into whichis Flown a mixture of chromium sesquioxide and alumina.A number of compounds of aluminium chloride and organicsubstances containing oxygen have been prepared by Walker andSpencer2 by the addition of aluminium chloride to the organicsubstances in presence of carbon disulphide.These compoundsconsist of eyuimolecular proportions of the chloride and organiccompound, for example, AlCl,,(C,H,),O, save in the instance ofmethyl mandelate and acetic acid, which form compounds containingfour molecules of the chloride.1VB.-Silicon hydride is formed by the direct union of the elementsat the temperature of the electric arc.Further, Dufour has denion-strated the reduction of silica by hydrogen. Moissan and Siemens4have investigated the solubility of silicon in molten met,als, forexample, zinc, lead, silver, tic, and aluminium ; from the solution insilver, part of the silicon separates out in crystalline form, which issoluble in hydroflnoric acid.Lead metasilicate 5 heated in a current of hydrogen yields a ‘ I silicite,’which is also formed together with metallic lead from the orthosilicate,from which it is concluded that two classes of lead silicates exist : (1)those containing the acid radicle in excess and yielding a ‘ I silicite ” ;(2) those containing the basic radicle in excess, which yield a silicite ”and metallic lead; these views being explained by the followingformtilx :Chlorostannic acid ( €€2S11C4), bromostnnnic acid (H,SnBr,), andiodostannic acid ( H,SnI,) undergo hydrolysis, which is most completein the case of the last-named acid ; pyridine and quinoline compoundsof the iodostannic acid are described by Rosenheim and Arons.GOF the stannichlorides, the following are described by vonBiron : Rb,SnCI,,, ZnSnC16,6H,0, FeSnC16,6H,0, SrSnC16,4H20, andLi,SnCI,,GH,O.Attempts to prepare corresponding cadmium, copper, silver, lead,Ann.Chim. Phys., 1904, [viii], 3, 20.Trans., 1904, 85, 1106.Contpt. rend., 1904, 138, 1040.Bid., 657.Simmonds, Trans., 1904, 85, 681.Zeit. nnorg. Chem., 1904, 39, 170.J. Rzm. Phys. Chem. sbc., 1904, 36, 45946 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.and thallium compounds were unsuccessful.The author regards thestannichlorides a s analogous to the platinichlorides, and Bellucci andParravano,l discussing the constitution of the stannates, express theview that they may be regarded as derivatives of the acid H2Sn(OH)6,analogous to H,Pt(OH),.The solutions of lead halides and sodium thiosnlphate are sensitiveto light, and on exposure to bright light deposit red precipitates, suchas Pb,S,CI, from the chloride, and Pb,S,I, from the solution of theiodide, whereas in diffused light or in the dark the sulphide isdeposited.2 Strijmholm describes a series of basic lead salts producedby the action of alkali salts on lead hydroxide suspended in water.Lead carbonate is formed by the action of ammonium carbonate in thecold on a solution of lead chloride, and on boiling is converted into thebasic salt, 2PbC03,Pb(OH),, which is also formed when lead carbonateis boiled with sodium sulphate or ~hloride.~VA.-Ruff and Geisel5 have studied the properties of nitrogensulphide, N,S,, which is produced from sulphur tetrachloride and am-monia in accordance with the equation :12SC1, + 16NH, = 3N4S, + 48HC1 + N,.It is attacked by dry hydrogen chloride, yielding ammonia, but nonitrogen ; liquid ammonia dissolves it, giving solutions which withlead iodide forni PbN,S,,NH,, and with mercuric iodide HgN,S,NH,.The authors conclude that the following is the most satisfactory repre-sentation of its constitution :This substance, when treated with ammonia, forms NiSNH, andS:S(NH,),, the first yielding mercuric thiodi-imide, N:S*NHg, and thelatter lead thiodi-imide, S:S<N>Pb.Herrenschmidt describes the industrial production of vanadium andsome of its alloys, which is of interest in association with the use ofthis metal in the manufacture of special steels. The vanadium isobtained in the slag formed by fusion of lead vanadate from the SantaMarta mines in Spain with sodium carbonate and charcoal.The slagcontains sodium vanadate, aluminate, and silicate together witah ironoxide. It is obtained as vanadic acid by oxidation in the fused statewith atmospheric oxygen, then extracting with water and precipitatingby sulphuric acid. Ferrovanadium containing 33 per cent. of vanadiumNAlti A. Accnd.Lineei, 1904, [v], 13, 11, 307 ; ibicl., [v], 13, 11, 324.Hofmanii and Wolff, Bcr., 1904, 37, 249.Salvadori, Gazxettu, 1904, 34, [i], 87,Conzpt. rend., 1904, 139, 635.Zeit. a%o'I'g. Chent., 1004, 38, 429.Bcr., 1904, 37, 1673INORGANIC CHEMISTRY. 47is formed by the ignition in the electric furnace of the precipitateformed by treating sodium vanadate with ferrous sulphate and sodiumcarbonate. Nickel vanadium containing 50 per cent. of vanadium isformed by reduction of a mixture of vanadium pentoxide and nickeloxide.Hall,l in describing the production of oxides of columbium and oftantalum from cohmbite (Haddam, Conn.), a130 discusses the use ofsulphur chloride in the formation of chlorides of the metals from theiroxides, showing that both columbium and tantalum pentoxides yieldthe pentachlorides ; further, titanic oxide, aluminia, and ferric oxideyield volatile chlorides when heated with sulphur chloride, whilsttungstic, vanadic, and molybdic oxides yield the oxychlorides ; zir-conium and tin dioxides give the chlorides only after prolonged heating,whereas silica and boron trioxide do not react with sulphur chloride.VB.-Arsenamide, AS(NH,),,~ is formed by the action of gaseousammonia on the trichloride, tribromide, and tri-iodide of arsenic a t-30" to -40'; it is resolved by water into arsenic trioxide andammonia, A t temperatures above Oo, it decomposes, and a t 60" iscompletely resolved into the imide, 2As(NH,), = As,(NH), + 3NH,.The imide a t 250' forms the nitride, AsN, and this a t higher tem-peratures yields nitrogen and arsenic.When phosphorus trichloride3 is led by means of hydrogen intoliquid ammonia a t - 78", the following reaction takes place :PCI, + 14NH, = 3(NH,Cl,3NH3) + NH:PNH,.At 0" the ammoniacal ammonium chloride decomposes, and between0' and 100" a further decomposition results in the production of theimide P,(NH),.Boron bromide and ammonia react in a somewhatsimilar manner, giving, however, the imide B,(NH), in the firstreaction.suggeststhe use of a solution of mercuric iodide in potassium iodide, with whicheach of the gases forms a characteristic precipitate.Some salts of trithio-oxyarsenic acid are described by McCay andFoster in the production of which the sodium salt, Na,AsOS,,llH,O,is used.This salt is produced by treating freshly precipitated arsenicpen tasulphide with magnesia, removing the magnesia with causticsoda, and precipitating the salt with alcohol.Bismuth tetroxide is formed when the trioxide is oxidised withalkaline potassium ferricyanide, whereas when oxidised with chlorineAs a reagent for phosphine, arsine, and stibine, LemoultJ. Amer. Chem. SOC., 1904, 26, 1235.Joannis, ibid., 364. Ibid., 478.Hugot, Conapt. rend., 1904, 139, 54.6 Ber., 1904, 37, 573; Zeit. a w g . Ch.em., 1904, 41, 45248 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in presence of an alkali both the tetroxide and the pentoxide areformed .1VIA.-Since the stability of endothermic compounds is greater thehigher the temperature, the conversion of oxygen into Ozone at hightemp eraturo should be possible.Clement 2 has, however, demonstratedthis not to be the case, and attributes the reported formation of ozoneat high temperatures to the formation of nitric oxide produced fromthe nitrogen present as impurity in the oxygen.Pfeiffer,3 by the investigation of the compounds of chromium andethylenediamine, has brought to light a series of complex substanceshaving the general formula [En,CrX2]X, in which formula “ E n ” isused t o represent the ethylenediamine residues ; in these compounds,only one X is in the ionic state. The compound [EnCr(SCN),]SCN isformed by the action of K,[Cr(SCN),] on ethylenediamine. It existsin two isomeric forms, namely, the a- and @-modifications ; correspond-ing chlorine compounds, [ En2CrC1,]C1, have been prepared, one ofwhich is green and the other violet.The author explains the iso-merism as arising from different stereometric arrangements, for whichthe following formulz are proposed, representing a cis- and trans-+ -modification :aX XI n these formuh, the chromium occupies the centre of a regularoctahedron, and is attached to ethylenediamine residues representedby a, X representing an electro-negative acid group, for example,SCN.The cis-Form can be distinguished from the tmm-form by it aloneproducing a closed ring with dibasic acid radicles. Experimentallyi t has been found that the a-modifications which are green do notform oxalates, such as the following : pjr-7::8\., awhereas the @-modifications do, hence the cis-type is associated withtho violet-coloured Compounds.1aHauser and Vanino, Zsit.anorg. Chem., 1904, 39, 381.a Ann. Physik, 1904, [ iv J, 14, 334. Ber., 1004, 37, 4255INORGANIC CIIEMISTI’LY. 49Hofmann and Hiendlmaierl prepare the ammoniuni salt ofchromatodiper acid by the action of ammonia and hydrogen peroxideon chromic hydroxide; it has the yellow colour of the sexavalentchromium compounds, and when treated with acids decomposes, givingonly transiently the blue of perchromic acid. The authors regard theperchromates as containing heptadic chromium, thus : CrO,*O*U*NH,,whereas the salts of chromatodiper acid contain sexavalent chromium, forexample, C r 0 2 < ~ : ~ : ~ ~ ~ and the conversion of the reddish-yellowchromates to blue perchromates is considered as analogous to thechange from manganates to permanganates.A new molybdenum carbide, MoC, has been obtained by Moissan byheating in the electric furnace a mixture of molybdenum, carbon, andaluminium.2Briggs 3 has obtained a, series of ammoniacal double chromates andmolybdates of the general formula M,’[RI~’(~RO,),ZNH,, in which AT’ iseither potassium or ammonium, [RI” may be copper, zinc, or cadmium,and R is either chromium or molybdenum.They arc compounds ofconsiderable stability, parting with ammonia at temperatures about200O. Tungsten does not form compounds of this type, but arnmonio-copper and ammonio-zinc tungstates have been prepared. Thesolution of molybdic acid in hydrochloric acid appears t o containchloromolybdic acid, of which Weinland and Knoll have preparedthe cerium, rubidium, pyridine, and quinoline salts.4Schaeffer5 has added much to our knowledge of the compounds oftnngsten, demonstrating the existence of only one potassium tungstenbronze, which has the formula K,W4012.Several paratnngstates aredescribed, and it is also shown that in the electrolysis of a solution ofthe normal sodium or potassium tungstate a t the anode there is firstformed the paratungstate, 5Na,0,12 WO,, and subseqnently the meta-tungstate, Na20,4WO,.VIB.-Harpf 6 finds that sulphur is oxidised at the ordinary tem-perature, especially in sunlight. The production of sulphur dioxidesufficiently explains the antiseptic properties of the element, withoutlthe suggestion that it is due to hydrogen peroxide produced byplants.Sulphur tetrachloride and the compounds it forms with otherchlorides have already been referred to.The production of alkalihyposulphites by the action in presence of ether of sulphur dioxide onsodium or potassium alloyed with lead or mercury is the subject of apatent. The compounds so obtained are very stable in contact withBer., 1904, 37, 1663; ibid., 3405.Tyans., 1904, 85, 677.Zeit. cmorg. Chem., 190 1, 38, 142.Conapt. rend., 1904, 138, 1556.Bw., 1904, 37, 569.(i Ibid., 39, 387.VOL. I. 50 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.air.1 Bucherer and Schwa1 be 2 attribute the following constitution t oy(Ho)*oNa which includes the one moleculeS(HO)*ONa’ sodium hyposulphite, O<of water of constitution this compound contains when salted out fromits solutions.The electrolytic production of hyposulphites has beenthe subject of several papera., Experimenting with aqueous solutionsof sodium thiosulphate, Thatcher shows the compound to be oxidisedforming tetrathionate when the solution is neutral or faintly alkaline,b u t when the solution is acid or strongly alkaline, sulphur, sulphite,and sulphate are formed.A number of well-defined crystalline polysulphides of the heavymetals have been obtained by Hofmann and Hochtlen with an ammo-niacal solution of a copper salt. Ammonium persulphide gives acrystalline precipitate, CuS,NH,, which is regarded as the cuproso-ammonium salt of H*S,H.From platinic chloride, the compoundPtS,,(NH4),,2H,0 is obtained ; this is a derivative of H,S,, havingthe constitution S5:Pt:[S,(NH,)],. Thallous chloride yields blackcrystals of Tl,S,. Auric chloride and ammonium persulphide giveyellow crystals, AuS,NH4, whilst the chloride in ethereal solutionwith sulphuretted hydrogen gives Au,S3. Iridium chloride (IrC1,)yields IrS15( NH,),. Whilst with bismuth chloride in aqueous solutionsthe sulphide is formed, in alcoholic solutions a compound crystallis-ing in black prisms of the composition Bi,S,,O,N,H,, is produced,which appears t o contain thiosulphate groups; for it the formulaNH4s4>Bi*S *S*Bi<szi40 is suggested.NH,S,O, 4 2 3With regard to tellurium,- it is stated that potassium tellurate isproduced by the oxidation of tellurium dioxide in presence of causticpotash with hydrogen peroxide.6 The electrolysis of telluric acidsolution in presence of potassium cyanide yields a brownish-violetsolution of colloidal tellurium; the replacement of the cyanide byammonium oxalate yields a blue hydro~ol.~The production of the hydrides of sulphur, selenium, and telluriumby the direct union of the elements has been established by F. Jones.*V1IA.-It would appear that the manganates of the alkalineearths hitherto described are mixtures, and that pure compounds ofBadische Anilin- & Soda-Fabrik (D.R.-P.148125).Zeit. a?iyew. CJiem., 1904, 17, 1447.Elbs and Becker, Zeit. Ekktrochem., 1904, 10, 361 ; Friesner, ibid., 265 ; Frank,Zeit. physiknl.Chena., 1904, 47, 641.B e y . , 1904, 37, 245, and ibid., 1903, 36, 3540.Gatbier and Wagenknecht, Zeit. anorg. Chem., 1904, 40, 260.Gutbier and Resenscheck, ibid., 264.Mem. Manchester Phil. Soc., 1904, 48, xvi, 1.ibid., 450INORGANIC CHEMISTRY. 51the type M,Mn,O,,H,O are formed by fusing a t 180' to 280' mixturesof the hydroxides of the alkaline earths with nitre and potassiumpermanganate ; these substances are mangani-manganates.1VIIB,-Moissan has redetermined the physical constants ofphosphorus trifluoride, pentafluoride, and oxyfluoride. Titaniumfluoride, TiF,, is formed, according to E m r i ~ h , ~ by the decompositionby heat of barium titanofluoride, BaTiF,. Ruff and Plato4 haveextended their investigations of fluorides prepared by the action ofdry hydrogen fluoride on the corresponding chlorides : TiF,, a liquidboiling at 284' ; SnF,, a hygroscopic, crystalline solid boiling at 705' ;SbF, is a viscid liquid (b.p. 155') ; with the trifluoride, it forms Sb3F1,or SbF,2SbF3, boiling a t 390°, also Sb,F,,,, which boils at 3S4'. Themolecular volumes of the fluorides are considerably less than those ofthe corresponding chlorides.The action of a mixture of chlorine and sulphur chloride on theheated oxides is proposed by Matignon and Gourion5 as a generalmethod for the production of anhydrous chlorides ; by this means theyhave prepared chlorides of silicon, aluminium, chromium, iron, zinc,manganese, nickel, and cobalt, also vanadium tetrachloride andvanadium trichloride. Vanadic acid is converted by this mixture inthe cold into the oxychloride, VOCI,.Tungsten oxide yields bothWO,Cl, and WOCl,. Barium sulphate, calcium sulphate, and calciumcarbonate are converted quantitatively into the chlorides. Boronchloride cannot be obtained in this way.By noting the action of the vapours on papers moistened withpotassium iodide and starch, Fireman and Portner find that phosphoruspentachloride commences to dissociate at 157-1 5S0, ferric chloride at122-1223', cupric chloride a t 344O, and chromic chloride a t 355'. Whencertain metallic chlorides are heated in sealed tubes with ammoniumchloride a t 380-410', those which dissociate more or less readily are re-duced to a lower stage of chlorinition and nitrogen is produced, whereasothers combine to form double compounds with ammonium chloride.7From the experiments of Gooch and McClenahan,s it appears thatwhen BaC12,2H,0, MgC1,,6H20, and A1C13,6H,0 are heated in dryhydrogen chloride, in some cases dehydration is favoured, in others thisaction is inhibited.E. Mullerg shows that potassium periodate is1 Auger and Billy, Comnpt. rend., 1904, 138, 500,3 B i d . , 789.Mosiatsh., 1904, 25, 907.Ruff, Plato and Graf, Beg.., 1904, 37, 673.Compt. rend., 1904, 138, 631 and 760.li J. Physical Ckem., 1904, 8, 600.7 Fireninn, J. Amer. C?~cm. Sac., 1904, 26, 741.9 Zeit. Blektrochem,, 1904, 10, 753.Amel.. J. Sci., 1904, [ iv], 17, 365.E 52 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.formed in the electrolysis of potassium iodate solutions made alkalinewith caustic potash containing 0.1 per cent.of potassium chromate ;further, that the yield is greatly increased by the presence of afluoride. As to the patented application of hydrofluoric acid for thepurpose of increasing the yield of chlorates in the electrolysis of alkalichlorides, it is shown by Foerster and Muller 1 that hydrofluoric acidhas no special advantage, acidification by any acid being as efficient.According to Tissandier, metallic iron heated a t 900' in a stream ofcarbon dioxide is converted into ferrous oxide, whilst Donau findswith the dry gas a t 1200O that magnetite is formed, and when soproduced is magnetic ancl crystalline.Hydrated cobalt chloride, CoCl,, 6H,O, dissolves in ethylene glycol,forming a violet-purple solution which becomes blue on heating ;further, this solution is acted on by light, becoming bluish-violet afterseveral weeks' e x p ~ s u r e .~ These observations are made by Oechsnerde Coninck, whoalso states that nickel and cobalt oxides are convertedinto their sulphrttes by crushing in a mortar with sodium hydrogensulphate.4Nickel carbonyl is more efficiently prepared hy working under apressure of 2-100 atmospheres, the formation then taking placeunder conditions which allow of heat being applied t o accelerate t h ereaction.5 Dewar and .Jones6 have described the action of thehalogens and several active inorganic substances on nickel carbonyl,showing that this compound usually breaks up so as to form carbonmonoxide and nickel compounds with the reagents employed ; thefollowing may be h k e n as typical : Ni(CO), + C1, = NiCl, + 4CO.I nno instance was the production of compounds of carbon monoxideobserved.Both gold and platinum are attacked under the influence of lightby fuming hydrochloric acid in presence of air ; the action is favouredby the presence of a trace of manganese chloride; in the absence oflight there is no action.7L. Wohler 8 finds that whilst platinum forms only the two oxidesPtO, and PtO, there are several hydroxides. Platinic oxide is both anacidic and basic oxide, whilst platinous oxide is essentially acidic.Platinic hydroxide is regarded as H,Pt(OH),, and from it the followinghydrates have been prepared : PtO,, 3H,O, Pt0,,2H20, and PtO,,H,O,the last of which is insoluble in hydrochloric acid or q u a regia.Potassium platinochloride, K,PtCI,, is technically prepared from the1 Zeit.Elektr-oclwm., 1904, 10, 781. Honntsh., 1904, 25, 181.Dewar, D.R. -P. 149959.Berthelot, Compt. rend., 1904, 138, 1297.Bull. A k a d . nay. Bely., 1904, 6, 803 ; ibid., 832.de Coninck, ihid., 833.Trans., 1904, 85, 203.Zcit. anorg. Chein., 1904, 40, 423INORGANIC CHEMISTRY. 53product of reduction of hydrogen platinichloride with sulphur dioxide ;the reduction of potassium platinichloride by potassium oxalate takeseffect only in presence of iridium, which acts as a catalytic agent.1Howe,2 in continuation of an investigation on the compounds ofruthenium, describes the preparation of chlororuthenates of the typeX,Ru(OH,)Cl, and their isomerides, the chlororuthenites, X,RuCl,,OH, ;the former of these, when treated with chlorine, yield chlororuthenatessuch as K,RuCI, ; corresponding broinicle compouncls are alsodescribed.Iridium sesquisulyhate, Ir,( S0,)3,xH,0, forms a series of well-defined alums with alkali sulphates, and also thallous sulphate.3Many observations have been made on the properties of colloidalmetals, especially of gold and silver ; for the production of colloidalsalts of the latter, Yaal and Voss recommended the use of alkaliprotalbates, or lysalbates, the latter of which can be formed by theaction of caustic alkali on egg-albumen and dialysing to remove excessof alkali Castoro,G by the addition of acrolein to hot faintly alkalinesolutions of gold chloride, has obtained gold hydrosols, varying incolour from sky-blue, amethyst, violet, pink, or purple, according tothe state of dilution. With ally1 alcohol, violet and ruby-red solutionsare obtained.Hydrosols of the metals of the platinum group can besimilarly produced.A considerable number of interesting communications have beenmade on the subject of the formation and constitution of alloys andamalgams, both the study of the curves of melting points of mixedmetals, as also the micrographical investigation, yielding valuableinformation. Moissan and O'Furelley 7 show that binary alloys ofmetals which do not form carbides inay be fractionally distilled inthe electric furnace, and that copper, zinc, cadmium, lead, and t i nmay be completely or partially separated in this way. Zinc andcadmium may be separated from their alloys with copper, the alloysof copper and lead behaving like ether and water; tin and leadcomport theniselves like mixtures of alcohol and water, and leave aresidue of pure tin, whilst copper and tin alloys behave like formicacid and water, yielding an alloy of constant boiling point containing60 per cent. of tin.Of special interest is the application of vanadium in the manu-facture of steels, the constitution and properties of which haveKlason, Be?*., 1904, 37, 1360.J. Amer. Chem. SOC., 1904, 26, 643 ; ibid., 942.Marino, Zeit. anorg. Cham., 1904, 42, 213.Hanriot, Conapt, rr.end., 1904, 138, 1044 ; Gutbies and Resenscheck, Zcit.Ber., 1904, 37, 3362.Zcit. aizorg. C'ILciiL., 1904, 41, 126.anorg. Chenz., 1904, 39, 112 ; Paal and hmberges, Bey., 1904, 37, 124.7 Cvuipt. wnd., 1904, 138, 165954 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.been studied by Guillet,l who, from their microstructure, forms threeclasses of .such steels : (1) Those containing 0.2 per cent. of carbonand less than 0.7 per cent. of vanadium, tho structure of whichresembles that of ordinary steel; (2) those having from 0.2 to 0.8per cent. of carbon and from 0.7 to 3 per cent. of vanadium, exhibitperlite structure; (3) those containing more than 3 per cent. ofvanadium, in all the carbon exists as vanadium carbide or doublecarbide of vanadium and iron. The vanadium steels are all sensi-tive t o thermal treatment, and their mechanical properties aregreatly influenced by such treatment. Guillet’s experiments on thecementation of carbon and special steels show that this process isinfluenced by the presence of other elements than carbon; the rate ofcementation is increased by manganese, chromium, tungsten, andmolybdenum, whilst nickel, titanium, silicon, aluminium, or tinretard the action. Experimenting with steels containing y-iron, andalso nickel and manganese, Guillet records interesting observationsshowing that carbon is dissolved by y-iron at the ordinary tempera-ture.P. PHILLIPS BEDSON.Covzpt. rend., 1904, 138, 367, 1600 ; 139, 426, 519, 640

ISSN:0365-6217    

DOI:10.1039/AR9040100030

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

ORGANIC CHEMISTRY-ALIPHATIC DIVISION.SPEAKING generally of the work done in the aliphatic series of carboncompounds during the year, i t cannot be said that the period has beenremarkable for any very striking discovery or for the initiation ofany important new departure; the aim of the investigations hasrather been directed towards the extension and amplification of theepoch-marking researches which have been accomplished within thelast ten or fifteen years.I n view of the enormous amount of work which has been done, itmould of course be altogether impossible t o give anything like Bcomprehensive account; the mere titles of the papers and authors’names alone would fill a very considerable portion of the allottedspace; even to make any appropriate selection from the papers whichare likely t o be of more general interest is no easy task since, not-withstanding this limitation, many highly interesting and importantcommunications have to remain without notice.I n many of the references which are included it has only beenfound possible t o give the merest indication as t o the nature of thework; in others, such as the applications of Grignard’s reaction, thechemistry of the carbohydrates and the polypeptides, it has beenconsidered necessary, in view of the increasing importance of thesubjects, t o make the accounts more complete.G r i g n a r d ’ s R e a c t i o 7%.Barbier, in 1899, appears to have been the first to suggest thesubstitution of metallic magnesium for zinc in certain syntheticaloperations, such as the formation of tertiary alcohols from ketonesby the action of alkyl halides in presence of tho metal.I n 1900,Grignard published a general method for the synthesis of alcohols andhydrocarbons, which consisted in first preparing the “reagent ” bythe action of magnesium turnings on an alkyl halide in presence ofperfectly dry ether, and using this to act on an aldehyde or ketone.Although the results are in many cases quite analogous to thoseobtained by the use of organo-zinc compounds, the preparation of th56 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.reagent and simplicity of working details offer very great advantagesover the older method, and the applications are much wider. Almostall classes of oxygen-containing organic compounds have beensynthesised by this method; Grignard, for example, used it in thefirst instance for preparing primary, secondary, and tertiary alcohols,carboxy-acids, hydroxy-acids, and hydrocarbons ; whilst others, suchas Valeur, Blake, Tissier, and Tschitschibabin, have by its meanssynthesised glycols, ketones, aldehydes, and ketonic acids.Thio-acidsand substituted hydroxylamines have also been obtained by use of thereaction, and very many later examples of its application will befound in the accounts given below.The formation of the “reagent” is generally expressed by thechange RX+Mg=R*Mg*X, and its reactions can, as a rule, all besatisfactorily represented as being due to the latter compound. Itseems probable, however, that the initial change is less simple andthat the compound RMgX only represents the final stage, since thenature of the solvent evidently plays an important part.From the earlier experiments, it appeared that ethyl ether was theonly efficient solvent, and Grignard considered that the initial com-pound was of the type RMgX,Et,O, in which the molecule of ether is“ firmly attached ’) to the organo-magnesium halide.Baeyer andVilliger, on the other hand, regard this initial product as an oxoniumcompound, the four groups being linked to quadrivalent oxygen :R R>O<&Later investigations have shown that certain other solvents may besubstituted for ethyl ether ; Hibbert and Sudborough have success-fully used ainyl ether, and Tschelinzeff 2 has brought about the actionwith dimethylaniline as solvent.Bruhl, Oerdt, and Malmgren hadalso obtained certain organo-magnesium compounds using xylene as asolvent, but in this case a higher temperature seems to be necessary.Tschelinzeff has more recently 3 made a further study of this questionas t o the part played by the solvent ; with regard to ether, he considersthat its function is to dissociate or sever the linking between thehalogen and nlkyl groups, and that the latter then react with theelements cf ether to give an oxoniuin compound, R,:O:RX, which bythe action of magnesium is converted to R,:O:MgR*X. In supportof this view he draws attention to similar cases in which ether causesa disruption of the linking in simple halides, as a result of whichmore complex compounds may arise.4Tram., 1904, 85, 933.Loe. c i t . , p. 4534.Compare KlobukotF, Zcit. physikal. C‘hem., 1889, 3, 429 and 476 ; Friedsl, 3~12.Ber., 1904, 37, 2084.Soc. eJ~iin., 1900, [ii], 24, 166 ; Archibald mid McIntosh, TrcLns., 1904, 85, 919ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 57Still more interesting is his conclusion that, in the reaotions whichtake place a t a low temperature, the ether acts catalytically ; using anotherwise inert solvent such as benzene, he finds that the formation ofan organo-magnesium halide takes place if an ether is added even inmere traces, and that the quantity formed is disproportionately greatin comparison with the amount of ether employed. Anisole, owing toits lesser volatility, is more suited for the observation of these effectsthan ethyl ether, although the influence of the latter was confirmed.The author further shows that tertiary amines also act catalytically,and that their influence is still more energetic than t h a t of ether.The changes are explained in a similar way, the alkyl-halogen linkingbeing severed and an intermediate product formed, which in this caseis the quinquevalent nitrogen compound :F.and L. Sachs have, in fact, shown that tertiary amines combinewith organo-magnesium halides to give additive compounds ; althoughthese on hydrolysis yield the original amine, they are themselvesso “strongly bound” that they do not show the reactions of theamine. This catalytic influence of tertiary amines, such as dimethyl-aniline, can be made use of in the practical working of Grignard’sreaction when benzene is employed as solvent.Tschelinzeff in another communication 2 draws attention to ageneral similarity between the reactions of organo-magnesium lialideson certain groups of oxygen and nitrogen compounds ; the nature ofsuch analogy may be gathered from the following few exaniples :H-OH + RMgX = OH-MgX + RH.HONK, + RMgX = H*NH*MgX + RH./O* MgX I \O*MgX-+ R-COR‘.0{R.CCH +2R’MgX = R*C-R’0C:O + RMgX = O:CR.O*MgX -+ O:CR*OH + OI€*&lgX.OC:NR + R’MgX = NR:CR’*OiVgX -+ O:CK’*NI€K + OH.MgX.Grignard’s reaction has been eniployed also in the preparation ofalkyl derivatives of elements other than carbon; it is shown, forexample, by Pfeiffer and Schnurmann3 that compounds such asstannic tetra-ethide or -pheoide may be advantageously prepared byBer., 1904, 37) 3089.Ibitl., 2081. IbkZ.) 31058 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the action of magnesium ethyl bromide on the halogen compounds ofthe metals. Salts of thallium dialkyl, such as TlMe,Br and TlEt,Cl,have been obtained by J. Meyer and Bertheiml from the action oforgano-magnesium halides on thallic chloride according to therelation TlCI, + 2MgRC1= TlR,Cl+ 2MgC1,. Magnesium methyliodide reacts with phosphorus trichloride at - 20' to give tetramethyl-phosphonium chloride, and under varying conditions mono-, di-, andtri-substituted phosphines may be obtained ; arsenic trichloride givesa product which, on oxidation, yields principally trialkylarsine oxide.2H3 d r o c ctr b o n s.The slow combustion of hydrocarbons at temperatures below theirignition points has been further studied by Bone and Stockings.3 Ithad previously been shown4 that the final products of oxidation ofmethane are carbon monoxide, carbon dioxide, and steam,and that form-aldehyde is formed as an intermediate product.Neither free hydrogennor free carbon is produced at any stage of the operation. Theauthors conclude that the oxidation of methane takes place in twosuccessive stages, namely, the production of formaldehyde and steam,and the further rapid oxidation of formaldehyde to carbon monoxide,carbon dioxide, and steam. The observations have now been extendedto ethane, and also to ethyl alcohol and acetaldehyde, and theprincipal conclusions arrived at may shortly be summarised as follows :under similar conditions, ethane burns much more rapidly thanmethane, and the oxidatioii takes place in both cases at temperaturesmuch below that at which steam is appreciably formed from oxygen andhydrogen.When ethane reacts with less oxygen than is required to burnthe whole of it t o carbon monoxide and water, there is no preferentialcombustion either of hydrogen or carbon. The combustion proceedsin several well-defined stages, involving the formation of oxygenatedcompounds; acetaldehyde is shown to be produced in the first stage,and there is much probability that ethyl alcohol is really the primaryproduct. I n the second stage, formaldehyde, carbon monoxide, andsteam result, and the formaldehyde finally undergoes further oxidationto carbon monoxide, carbon dioxide, and steam, formic acid beingprobably an intermediate product.Hydrogen or methane, or both, may appear in the products due tothe decomposition of the vapours of formaldehyde and acetaldehyde byheat and a little ethylene may result from the decomposition ofBer., 1904, 37, 2051.Auger and Billy, Compt. rend., 1904, 139, 597.Trans., 1904, 85, 693.Bone and Wheeler, Trans., 1903, 83, 1074ORGAXIC CHEMISTRY-ALIPHATIC DIVISION, 59ethane itself.Carbon is not liberated below the ignition points ofthe reacting mixtures, but if the temperature is allowed to rise t o theignition point an explosion occurs with the liberation of carbon andhydrogen, together with some acetylene and ethylene. Ethyl alcoholreacts with oxygen far more rapidly than ethane under similarconditions, and the operation involves, as in the case of ethane, thesuccessive formation of acetaldehyde and of formaldehyde with carbonmonoxide. I n the case of acetaldehyde, it was shown that, in additionto formaldehyde, considerable quantities of methane and carbonmonoxide are formed owing to the purely thermal decomposition of theacetaldehyde.Although methyl alcohol could not be detected among the productsof the slow combustion of methane, the authors have shown that, inthe case of ethane, ethyl alcohol is formed. According t o Arm-strong's view,l the hydrocarbon in the initial stage of the operationmerely undergoes hydroxylation, and when this has taken placefurther hydroxylation takes place more rapidly, so that the initialproduct may escape observation.More recently,2 Bone and Wheeler have extended these investiga-tions to the study of ethylene, and their principal conclusions may bebriefly stated as follows :There is no preferential combustion of either carbon or hydrogenwhen ethylene reacts with oxygen in quantity insufficient to burn i tcompletely.Formaldehyde is the most prominent intermediate oxida-tion product, and the formation of aldehydes precedes that of steamand oxides of carbon. There is no separation of carbon or liberationof acetylene, even in the explosive combustion of ethylene, exceptwhen the oxygen present is insufficient to burn the hydrocarbon to form-aldehyde; under these conditions, the excess of ethylene is thermally de-composed, yielding carbon, hydrogen, methane, and traces of acetylene.has shown by a variety of reactions that formaldehyde iscontained in ordinary atmospheric air, and he gives the proportion as2 to 6 grams per 100 cubic metres.The quantity was estimated bypassing the filtered air through U-t ubes containing mercuric oxideand heated to 250'. I n this way, the formaldehyde is oxidised tocarbon dioxide, and this is absorbed in potash bulbs, allowance, ofcourse, being made for the carbon dioxide originally present as suchin the air. points out that when air contains more than0.5 to 1 gram of formaldehyde in 100 cubic metres it ceases to berespirable ; Henriet consequently suggests that the large proportionwhich he found in normal air may have been present in some form ofcombination, such, for example, as methylal.HenrietGautier€roe.Boy. SOC., 1904, 4, 86. Trans., 1904, 85, 1637Ibid., 139, 67. i( Compt. rend., 1904, 138, 203, 127260 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Trillat finds that various combustible substances, such as coal, peat,wood, cork, caoutchouc, and tobacco, when burnt in a glass tube in acurrent of air, give, in all cases, quantities of formaldehyde varying from1/1000th to 1/100,00Oth of the weight. of substance burnt. From theseresults, it is concluded that the formaldehyde found by Henriet inatmospheric air has its origin in processes of limited combustion ofcompounds containing carbon and hydrogen.A l c o h o l s .Primary alcohols may be prepared from the corresponding amidesby acting with metallic sodium on the amide dissolved in ethylalcohol ; on adding water and distilling in steam, a mixture of amineand primaryalcohol passes over, which can be separated in the usualway by means of an acid.Bouveault and Blank2 have in this mayobtained n-hexyl alcohol from the amide of 1%-hexoic acid and benzyl-carbinol from phenylaceticFor the preparation of tertiary alcohols by means of Grignard’sreaction, the following additional method has recently been publishedby Grignard.I The magnesium alkyl halide RMgX is first acted onby dry carbon dioxide in ethereal solntion, when, as the author has pre-viously shown (1901), the additive compound R.CO,*MgX is formed.If, now, the excess of carbon dioxide is removed and the product isfurther acted on by a compound It‘MgX, the following change takesplace :the latter compound on hydrolysis then yields the correspondingtertiary alcohol.Diethylisoamyl-, isobntylcliisoamyl-, and phenylcliethyl-carbinolswere obtained in this way.Although tertiary alcohols normally result from the action of Grig-nard’s reagent on ketones, it was found that in the case of un-saturated ketones in which the double linking is situated near thecnrbonyl group the product of the reaction was an unsaturated hydro-carbon, since the tei tiary alcohol became dehydrated during theprocess.Fallenberg5 now finds, however, that in the cases of mesityloxide and phorone it is possible to isolate the tertiary alcohols whichare formed in the first stage, and that they can be distilled unchangedin a vacuum. Mesityl oxide, when acted upon by magnesium methyliodide, gives a product which, when decomposed by dilute acetic acid,yields 2 : 4-dirnethylpentene-(3)-01-(2), CMe,:CH*CMe,*OH, which is aCompare also Guareschi, Atti 12. Accnd. Xci. 7’0riiz0, 1904, 39, 418.R*CO,*MgX + 2RMgX = O(MgX), + CRR,’*OMgX ;Compt. rcnd., 1904, 138, 1613.Compt. ~ c n d . , 1904, 138, 162.Ibid., 148.6 EL!?..) 190-1, 37, 357sORGANIC CHEMISTRY-ALIPHATIC DIT'ISION. 61colourless liquid boiling at 46'/14 inm. When this tertiary aIcohol isdistilled under the ordinary pressure, it loses water, giving the dimethyl-pentadiene which Grignard obtained (1 900) in a single stage. Phorone,when similarly treated, gives 2 : 4 : 6-trimethylheptadiene-(2 : 5)-01-(4),CMe: CH*CMe(OH) CH:CMe,.This alcohol crystallises in long, white needles, which melt at 5 7 * 5 O ,and on repeatedly distilling it over sodium it yields a colourless liquidhydrocarbon, which proves to be trimethylheptntriene,CMe2:CH*C(:CH,)-CH:CMe,.For the characterisation and pnrification of certain alcohols,Bonveault 1 recommends the conversion of the alcohol into its pyruvicester, and of this into its seniicarbazone.Primary ancl secondaryalcohols give in this way seinicarbszones which are insoluble in water,but which crystallise well froin organic solvents ; from these com-pounds, the alcohols can be regenerated by the action of alcoholicpotash.Tertiary alcohols are decomposed when boiled with pyruvicacid, yielding an ethylenic hydrocarbon and water.Kling and Viard suggest a method of distinguishing primary,secondary, and tertiary alcohols which is based on their differentbehaviour when heated. Tertiary alcohols become dehydrated at thetemperature of boiling iiaphtlialene ( 21S0), whilst primary andsecondary alcohols are unchanged. A t the boiling point of anthracene( 360°), both secondary and tertiary alcohols are decomposed, onlyprimary alcohols remaining intact. These changes can be followedby determination of the vapour density a t the temperatures mentioned.A Id e ? q d e s and l i e t o n e s .Several new methods have recently been published for the syntheticalpreparation of aldehydes.Tschitschibabin,3 for example, finds thatthe esters of orthoformic acid react with organo-magnesium haloidsto give acetals, and these, when hydrolysecl with dilute sulphlnric acid,yield the corresponding aldehydes,CH(OEt), + RMgI = CHR(OEt), + EtO*MgT.B6hal and Sommelet4 first prepare the ethers of a-glycols of thetypes OH-CR,*CH,*OX ancl OH*CRR,*CH,*OH (from ethyl ethoxy-acetate, or from ketones o f . the type R*CO.CH,*OEt, by means ofQrignard's reaction). These are then clecomposed by heating withdry oxalic acid to 11 0-1 15", when the corresponding substitutedaldehydes are produced, the change proceeding probably as follows :OH*CR,*CH,*OX --+ CR,:CH*OX --+CR,:CH*OH -+ CR,H*CHO.Compt. rend., 1904,138, 984.Bcr., 1904 37 186.Con@. rend., 1904, 138, 89.Ibid., 117262 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Blaise 1 shows that certain lactides on distillation give aldehydes inthe following way : CHR<gP!E>CHR = 2CO + SRCHO, a smallproportion of an unsaturated acid being simultaneously formed,Starting from a fatty acid, say hexoic acid, he first obtainsthe a-monobromo-derivative, and from this the hydroxy-derivative,which on heating gives the lactide, and this on distillation the alde-hyde as above. He is of opinion Ohat the aldehyde results from thedecomposition of the lactide and not of the hydroxy-acid itself. ButLe Sueur, in an earlier has found that in the case ofhydroxystearic acid the action of heat is to give carbon monoxide,formic acid, a lactide, and 50 to 60 per cent.of margaric aldehyde,C,,H,,*CHO. Since this change can take place at a lower temperaturethan that a t which the lactide is decomposed, he concludes that thealdehyde is formed directly from the acid and not from the lactide.Margaricaldehyde, obtained by Le Sueur in this way,, is a whitesolid melting a t 35-36’, which slowly polyruerises on keeping; onoxidation, it yields margaric acid, which is perhaps identical with theproduct obtained by Kraft, in 1879, from methyl heptadecyl ketone.Blaise (Zoc. c i t . ) recommends the above series of operations as a meansof systematically degrading certain acids, and he has applied themethod for the degradation of hexoic, pelargonic, lauric, myristic, andpalniitic acids.A method of producing aldehydes of the type CRR’H*CHO fromketones, which is said to be of general application, has recently beenpublished by D a r ~ e n s .~ The ketone R*CO*R’ is mixed with ethylchloroacetate and acted upon by sodium ethoxide in the state ofpowder. The result is the formation of an unstable acid, which splitsup into carbon dioxide and the aldehyde CRR’H*CHO.It has been shown by Blank and Finkenbeiner and by Hardenthat when formaldehyde is acted on by hydrogen dioxide in alkalinesolution the result is free hydrogen and a metallic formate.now shows that if the action takes place in neutral or acid solutionno formic acid is produced, but only carbon dioxide and free hydrogen.I n these reactions, the hydrogen appears to come from the form-aldehyde, and not from the hydrogen dioxide, since barium peroxidegives similar results.The peroxides of lead and manganese act onformaldehyde to give formates.indicate that even in dilute aqueous solution formaldehyde existspartly in a polymerised form. Diformaldehyde, C2H402, is said toCompt. rend., 1904, 138, 697. Proc., 1904, 20, 14.3 Tq-ans., 1904, 85, 833. Conapt. rend., 1904, 139, 1214.Bcr., 1904, 37, 515. Anitaleit, 1904, 334, 1GeisowCryoscopic determinations made by Litterscheid and ThimmORGANIC CHEMISTRY-ALIPHATIC DIVISION. 63separate in flakes when the vapour of formaldehyde is passed intochloroform at about 130°, the change being greatly increased bysun1ight.lBy heating trioxymethylene with water, Segewetz and Gibellohave obtained four polymerides of formaldehyde which differ inmelting points and solubilities from the modifications already known(paraformaldehyde, its hydrate, trioxymethylene, and a-trioxy-methylene). The molecular weights of these new modifications issaid t o approximate to 60 in the freshly prepared solutions, whilstthe vapour density in each case indicated the number 30.The sametwo authors 3 have found that the condensation of trioxymethylene toa mixture of sugars is easily brought about by meam of sodiumsulphite, the change taking place much more readily than the corre-sponding condensation of formaldehyde by bases.The nature of theresulting sugars depends somewhat on the proportions and on theconditions of the experiment ; from the action of phenylhydrazine onthe resulting mixtures, they were able to identify forrnosazone,glycerosazone, and, under certain conditions, a-acrosazone.Hydracrylic aldehyde, CH,(OH)*CH,*CHO, has been obtainedby Nef4 as a colourless oil boiling at 90' under 18 mm.pressure; i t is prepared by heating acrolein with four times its weightof water a t 100' for about 20 hours. .It is very easily soluble inwater, but dissolves only very slightly in ether; heating withpotassium hydrogen sulphate reconverts it into acrolein, and by theaction of dilute alkalis it gives rise t o crotonaldehyde. The semi-carbazone is crystalline and melts at 114'.r-Lactic aldehyde, CH,*CH(OH)*CHO, appears to be incapableof existing in the isolated form, but was obtained5 as acetate bythe action of silver acetate on a-iodopropaldehyde. This acetateis a dark oil having an aromatic odour, which boils at 55-65Ounder 19 mm.pressure and gives a crystalline semicarbazone. Vhenheated with water, it yields acetol and acetic acid (see page 68).Lnpworth in the course of an extensive study on the addition ofhydrogen cyanide to carbon compounds has recently shown6 that theaddition is usually much more easily accomplished when potassiumcyanide is present; carbonyl compounds can, in fact, in many casesactually remove hydrogen cyanide from an alkaline solution of potassiumcyanide. I n a more recent c~mmunication,~ this author describes theresults of the action of potassium cyanide on mesityl oxide.It isshown that the initial product is mesitononitrile, and this, on prolongedKorber, P/mrnz. Zeit., 1904, 49, 608.BdI. SOC. chim., 1904, [iii], 31, 434.LOC. cit., p. 266.Conapt. re?tcl., 1904, 138, 1225.L4miaZen, 1904, 335, 219.Trans., 1903, 83, 995.7 Ibid., 1904, 85, 121464 AKNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.heating, is hydrolysed by the resulting potassium hydroxide, yieldingmesitonic acid,C(CH,),:CK*CO*CH, + KCN + 2H,O ==C0,K*C(CH,)2*CH,*C0.CH, + NH,.I n one operation, therefore, it is possible in this way to synthesise ny-ketonic acid from an up-unsaturated ketone.Cnrbo h y d r a t es.Bertrand gives a complete historical account of the chemistry ofsorbose and sorbidol together with a concise summary of his remarkablework on the oxidation of various polyhgdric alcohols and sugars bythe agency of the “ sorbose bacterium.” I n the latter organism, it ispointed out, we have the equivalent of a powerful chemical agent bywhose assistance it is possible to prepare many new compounds and togain much knowledge with regard to the constitution of various carbo-hydrates and allied substances.I n the case of polyhydric alcohols, theeffect of its action is to bring about the oxidation of a -CH*OH groupto :GO, and consequently the formation of a ketose; in this way, theketoses-dihydroxyacetone, erythrulose, arabinulose, sorbose, l~vulose,perseulose, and volemulose-were obtained from the respective poly-hydric alcohols-glycerol, erythritol, xrabitol, sorbitol, mannitol, perseitol,ancl volemitol.Glycol, Lxylitol, arid d-dulcitol are not attacked, theirimmunity being evidently conditioned by stereochemical structure ;according to the author’s view, a -CH*OH group is only open to attackby the organism when its hydroxyl group is not adjacent to a hydrogenatom on the same side in the configuration formula.I n the case of reducing sugars, it is found that all are attacked;nldoses are oxiclised quantitatively to the corresponding inonobasicacids, whereas ketoses are only slowly altered and give no characteristicproducts.Amongst this author’s most recent observations which are describedin this paper may be mentioned the reduction, by sodium amalgam, ofsorbose to a mixture of d-sorbitol and d-iditol.The properties ofdihydroxyaceto?ze, which is easily obtained by the above-mentionedmethod, have also been more completely studied, and it is shown that,contrary to previous statements, this carbohydrate is capable of under-going alcoholic fermentation with yeast, although with difficulty.From one gram of dihydroxyacetone, bhe yield of alcohol amounted,after 10 days, to 15-125 milligrams, according t o the kind of yeastemployed.. As already mentioned, ordinary erythritol yields thecorresponding ketose, erythrulose ; the latter, when reduced by sodiumA m . Chinz. Phys., 1904, [viii], 3, 181ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 65amalgam gives rise to two tetritols ; one of these is ordinary i-erythritoland the other is the hitherto unknawn d-erythritol, which is the opticalantipode of the product which Maquenne previously obtained (1 901)from xylose by degradation and reduction.On oxidation with nitricacid (1 : S ) , this new modification gives rise to ordinary d-tartaric acid.When an nldose sugar is oxidised, under the influence of thisorganism, to the corresponding monobasic acid, if it should happenthat an '' attaakable " secondary alcoholic group remains, the oxidationmay proceed further with formation of the corresponding keto-acid.d-Glucose, for example, gives glnconic acid which contains a -CH*OHgroup liable to attack ; the result of further oxidation, by the sameagency, is (' oxygluconic " acid.OH H OH OH OH H OH OHOH H OHH 6 H H--f CO,H*~-~-~*CO*CH,*OH.The latter acid appears to be identical in every way with that whichBoutroux, in 1888, prepared also by the fermentation of glucose; inthis case, however, the active ferment was lost, and in consequencethe acid had been but little studied.It was formerly supposed that only primary hydrazines were capableof producing osazones from aldoses o r ketoses, the reaction involvingoxidation of the C.H*OH or CH,*OH group adjacent to the CO group.But Weuberg, in 1902, showed that phenylmethylhydrazine can givean osazone by direct action on lasulose and on some other ketoses,and it appeared, in the first instance, that this behaviour was limitedto ketoses and to osonee.Ofner now states 1 that d-glucose can reactdirectly with phenylmethylhydrazine to give an osazone identicalwith that which Neuberg obtained from levulose and Fischer fromglucosone. But Neuberg2 points out that if the conditions which herecommended are followed the distinction is still valid. With regardto the action of unsyminetrical secondary aromatic hyclrazines suchas phenylbenzylhydrazine, it would appear that these can react withthe phenylhydrazones of aldoses to give osazones, but not with thesugars themselves. Pure phenylbenzylhydrazine is, in fact, said to bewithout action on either dextrose or hvulose, and the product pre-viously obtained by Neuberg from lzevulose, and supposed to bed-fructosephenylbenzylosazone, is now shown to be a mixture ofphenylosazone and phenylbenzylosazone, and is only produced whenBsr., 1994, 37, 3362.YOL.I.2 Ibid., p. 4616.66 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the phenylbenzylhydrazine contains phenylhydrazine. I n this con-nection, it may be of interest to mention a recent observation of thewriter that glycollic aldehyde readily reacts with phenylbenzylhydr-azine to give the phenylbenzylosazone of g1yoxal.lMany acid hydrazides, such as p-bromobenzoylhydrazide, react withaldoses to give hydrazones which are insoluble or sparingly soluble inmost solvents. From these compounds, the original sugars areeasily regenerated by the action of dilute sulphuric acid, benzaldehyde,or pyridine. It is stated that ketoses do not give hydrazones bythis treatment.2In order to distinguish aldoses from ketoses, Berg proposes a methodbased on the fact that the former are readily oxidised by brominewater to the corresponding hydroxy-acids, and that the latter give anintense yellow colour with ferric chloride.The sugar to be examinedis heated for 10 minutes with bromine water to 60--70°, the excessof bromine expelled, and the product tested with ferric chlorideand a drop of hydrochloric acid. The aldoses examined-glucose,galactose, arabinose, and xylose-all gave an intense yellow colourwhen submitted to this treatment, whereas lmwlose and sorbose gaveno colour.It has been shown by the writer4 that ketohexoses and substanceswhich yield them by hydrolysis, when oxidised in presence of ironby hydrogen peroxide, or by chlorine, a t 80-90°, yield a product which,when heated with phenylhydrazine-p-sulphonic acid, gives a brownish-pink dye-stuff. This reaction appears to be very characteristic ofketohexoses ; the aldoses are only very slowly oxidised under similarconditions and the lower sugars do not give a similar colour with thehy drazine compound.For the purpose of separating and identifying the constituents ofa mixture of certain sugars, VotoEek and VondrACek recommend aprocess of successive treatment with different hydrazines, such asphenyl-, phenylmethyl-, and diphengl-hydrazines.The strength of thesolution is adjusted so as to contain about 5 per cent. of the reducingsugars, and an equivalent quantity of a suitable hydrazine is added inthe form of acetate, The resulting hydrazone is filtered off and thefiltrate is treated with a second hydrazine, which causes the separationof another sugar as hydrazone or osazone, and these operations maybe continued even for a third sugar.Mannose and galactose, for example, can be separated by first pre-cipitating the rnannose as phenylhydrazone, and, secondly, the galactose1 Compare Ruff and OllendorfY, Ber., 1900, 33, 1806.2 Kahl, Zeit. Ycr.Deut. Zuckerind., 1904, 584, 1091.3 Rid/. Xoc. chim., 1904, [iii], 31, 1216.Ber., 1904, 37, 3854. Byit. Assoc. lieport, 1904ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 67as phenylmethylhydrazone. A mixture of galactose and glucose issimilarly identified by acting successively with phenylmethylhydrazineand phenylhydrazine, which give the corresponding hydrazone andosazone respectively.Morrell and Bellars * have continued their investigations on theformat.ion of osones from hexoses, pentoses, and bioses by the generalmethod of oxidation with hydrogen peroxide in presence of ferrous ironand have traced a connection between the diminution of opticalactivity, change in reducing power, acidity, and yield of osazone duringoxidation.They show that glucose, fructose, galactose, arabinose,rhamnose, and maltose give crystalline compounds with guanidine ;these compounds form strongly alkaline aqueous solutions from whichthe guanidine can be completely removed by acids.By keeping milk-sugar for some time in contact with calciumhydroxide, isosaccharin and metasaccharin were obtained by Cuisinierand by Kiliani respectively (1882-1883) ; Kiliani and Loeffler nowfind that parasaccharin is also produced in considerable quantity.When the latter substance is oxidised by hydrogen peroxide in presenceof iron, " degradation " occurs with formation of parasaccharopentose,C,H,,O,. This is a crystalline substance which reacts with phenyl-benzylhydrazine to form a hydrazone, and has the constitutionCH,(OH)* CH,*CO*CH(O H) CH,* OH.From this, it is concluded that parasaccharic acid must have theformula CH,( OH)*CH,* C( CO,H)( OH) CH( OH) CH,*OH.By oxi-dising the barium salt of the latter acid with strong nitric acid(sp. gr. 1-39), an easily soluble crystalline acid is obtained, whichproves to be hydroxycitric acid, C,H,O,,H,O ; this has hitherto beenbut little known and only scantily described.It is tribasic andgives characteristic copper and dipotassium salts. These authorspoint out t h a t the modifications of saccharic acid may convenientlybe identified by means of their crystalline quinine salts.The action of calcium hydroxide on I-arabinose gave rise t o con-siderable quantities of calcium lactate, and, in addition, salts havingthe composition Ca(C,H90,), and Ca(C,H,,O,), mere obtained. Theformation. of a six-carbon acid from a five-carbon sugar is explained bysupposing that part of the sugar first breaks down into simpler parts,which then unite to build up synthetically the more complex molecule.3It would appear that acetol should appropriately be considered inconnection with the family of the carbohydrates, since it may be regardedas the methyl derivative of the first sugar or methyldiose.Nef, in ahighly interesting course of researches on the disociation of compoundsBrit. Assoc. Kcport, 1904.Ber., 1904, 37, 1196 and 3612.Kiliani and Koehler, Zoc. cit., p. 1.210.F 623 ANNUAL REPORTS ON THE PROGRESS OP CHEMISTRY.belonging to the glycol OF glycerol series,l has made a careful study ofthe formation, properties, and relationships of acetol. He shows thatit is produced, anlongst other substances, when glycerol is slowlyled through a tube which is filled with pumice and heated to 430-450O.It is also formed when a-bromopropionaldehyde is heated with potassiumacetate or formate.Further, he finds that, when a-iodopropionaldehydeis heated with silver acetate, a product is obtained which he identifiesas the acetate of r-lactic aldehyde. When this acetate is heated withwater to looo, it yields acetol and acetic acid. I n view of these fads,the question arises whether acetol and lactic aldehyde may not beidentical or tautomeric. It is shown, however, that on heating acetolwith acetic anhydride only acetd acetate is produced quite freefrom the acetate of lactic aldehyde, the two acetates being readilydistinguished by their semicarbazones ; the acetol compound melts at145", and that of lactic aldehyde at 163". This author arrives a t theconclusion that acetol is identical with hydroxyacetone and that theisomeric lactic aldehyde cannot exist in the isolated condition, butbecomes transformed into acetol.Owing to the observation that acetol, when oxidised with alka-line cupric oxide, gives rise to lactic acid, Kling (1903) consideredthat, in solution, acetol exists partlyin a form different from hydroxy-acetone, and suggested the possibility of the group :C--C:.He has'\/0later attacked this question by means of Grigoard's reaction, sinceit had been shown by Grignard that compounds cont;iining this group,when acted iipon by organo-magnesium halides at low temperatures,give secondary alcohols of the type OH*CHR*CH,X, whereastertiary alcohols are produced from compounds in which the -0-group is present. The behaviour of acetol and its esters towards thisreagent is found to be that of a ketonic compound, tertiary alcohols,or their derivatives, being obtained.The action of dilute acids on cellulose causes under certain con-ditions, a destruction of the tenacity of the fibre, and the resultingpowder has been called " hydrocellulose," the formula assigned to itbeing C1,,H2,0,, (Girard, 1875-1881).Stern has recently examinedthe behaviour of flax and cotton cellulose when boiled with 5 per cent,sulphuric acid, and finds that instead of a gain in weight there isalways a loss, and a certain amount of soluble matter is a,lso formedof which a portion appears to be d-glucose. The friable mass remain-ing is shown by analysis to have the same composition as t,he originalAmalen, 1904, 335, 191-333.T~mis., 1904, 85, 336.Compf.Tend., 1803, 137, 756ORGANIC CHEMISTRP-ALIPHATIC DIVISION. 69cellulose. The author concludes that hydrocellulose is not formed,and that the only essential change, apart from the disintegration, isthat a portion of the cellulose becomes hydrolysed into soluble pro-ducts.Cross and Bevan, however, consider that these differences aredue to the fact that the conditions of Stern’s experiments are notaltogether the same as those employed by Girard, and they propose toretain the name of hydrocellulose for the products of the action ofacids on cellulose. These, they say, are certainly hydroly sed, althoughin many cases they may have the same composition as the parentsubs tanc:.Knechtl shows that when cellulose is treated with nitric acid ofsp.gr. 1.415 a ‘‘ labile ” nitrate having the composition CBHl,O,,HNO,is obtained. When this is decomposed by water, a product free fromnitric acid results, which contains 4 per cent. more water than theorigmal cellulose, and appears to be a hydrate. The process is there-fore quite analogous to the mercerisation of cotton by alkalis ; in thiscase, the compound (C,H,,O,),,Na,O is probably first formed, and thisie decomposed by water, forming sodium hydroxide and a celluloseIt is customary to assume that the molecular formula for cellulosemust be represented by a multiple of the empirical formula, thedouble value C,,H,,Olo being often regarded as the minimum. Thereasons usually advanced in favour of this assumption, such as theinsoluble and colloidal nature of cellulose and the existence of a penta-nitrate, are considered by Green * to be altogether insufficient and,until further definite experimental evidence is forthcoming, he prefersto employ the single formula C6H,o0,5.He shows, further, that nosatisfactory constitutional formula has yet been proposed which givesan adequate indication of the chemical behaviour of cellulose, andsuggests that it might be regarded as an inner anhydride of glucoseCH(OH)*CH*CH*OHCH(OH)*C K* CH,(C6H100,)2,H20*liaviug the constitution I >o>o *This formula would account for a large number of important facts,among which the following may be mentioned.(a) That the highest nitrate (assuming the c6 formula) is thetrinitrate; (71) that the absence of a carbonyl gr’oup is indicated bythe behaviour of phenylhydrazine and hydroxylamine ; ( c ) that w-bromo-methylfurfural results by the action of dry hydrogen bromide; (d) theproduction of isosaccharic and dihydroxybutyric acids by the action ofmilk of lime on oxycellulose, and (e) the formation of hydroxypyruvicacid when cellulose nitrate is heated with dilute sodium hydroxide.2 Eeit.F M ~ . Texf, Ind., 1904, 3, 97. BET., 1904, 37, 54970 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Several objections to this formula are raised by Cross and Bevan 1and are answered by Green.2 The objection that the formula cloes notindicate the possibility of a tetra-acetate would appear to be disposedof, since a determination of the acetyl groups in this supposed tetra-acetate by Perkin's method proves it, in reality, to be a triacetate.3Skraup and Konig, in 1901, obtained a biose, C,,H,,O,,, fromcellulose by treatment with acetic anhydride and sulphuric acid, anddecomposition of the resulting octoacetylcellulose with alcoholic potash.This sugar (cellose) has been further examined by Maquenne andGoodwin.* With hydroxylamine, it reacts to give a viscous oxime, andby action of carbanil it is converted into a hexaphenylurethane,C12H20010( CON*C,IE,)6, which appears therefore to be derived from ananhydride containing only six hydroxyl groups.When oxidised bybromine in presence of water, cellose gives, as an uncrystallisablesyrup, '' cellobionic acid," C,,H,,O,,, which reduces Fehling's solutiononly after hydrolysis ; this direct format.ion of a corresponding mono-basic acid on oxidation proves the prosence of an aldoae group in themolecule of cellose.the action of carbanil (phenyl-carbimide) on various other sugars, such as arabinose, xylose, dextrose,and lactose; they find in every case that each hydroxyl group isreplaced by the carbamate residue.that the semi-carbazones of many of the sugars are easily obtained, but they are notvery well suited for the identification of the latter, since the meltingpoints are not sharply defined.From results obtained by the cryoscopic method, SabaneeB, in 1890,estimated the molecular weight of glycogen to be about 1620, corre-sponding t o the formula (C,Hl,O,),o. Similar determinations haverecently been made, using improved modern apparatus, by Nme.Gatin-Gmiewska, who comes to the conclusion that either the previousresult is far too low or t h a t the substance is insoluble, and its mole-cular weight cannot be determined.The numbers actually obtainedby the author would point to a molecular weight of 140,000.These authors have also examinedThey show alsoA c i d s a n d E s t e r s .A method for the characterisation of fatty acids has been suggestedby Locquin,' which consists in converting them into the correspondingZed. Farb. Z'ext. Ind., 1904, 3, 197.Cross and Bevan, however, still consider that the evidence is not conclusive andsuggest that a fonrth acetyl group may be present which behaves differently to theother three.Ibid., p.309.Zeit. Farb. Text. Ind., 1904, 3, 441.* Rzdl. Soc. chirm., 1904, [iii], 31, 854. Compt. revd., 1904, 138, 633.Compt, Texd., 1904, 138, 1274, Bzcll. Xoc. c ? ~ i m . , 1904, [iii], 31, 1075ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 71hydroxyacetone esters by the action of chloroacetone upon the sodiumsalts :R*CO*ONa + CH,Cl*CO*C€€, = R*CO*O*CH,*CO*CH, + NaCl.These esters can then be readily identified by means of their semi-carbazones, which are easily purified and have sharply-defined meltingpoints.As an example of one of the ways in which Qrignard’s reaction maybe employed in the synthesis of acids may be mentioned the simpleformation of pivalic (trimethylacetic) acid from te&.-butyl chloride,‘The additive compound which is formed by the action of magnesiumis, in this case, acted on by dry carbon dioxide in ether solution,when a 30 per cent.yield of pivalic acid is obtained on hydrolysis.tert.-Amy1 chloride similarly gives a 60 per cent. yield of aa-dimethyl-butyric acid :R3C‘*MgC1 --+ R3C*C10,*MgCl -+ R3C*C02H,An isomeride of oleic acid has been obtained by Ponzioe froma-bromostearic acid ; the latter was first converted into the corre-sponding iodostearic acid (by the action of alcoholic potassium iodide),and this was then decomposed by alcoholic potash. The formulaCH3(CH2),4*CH.:CH*C0,H is assigned by the author to this acid,which, on potash fusion, yields palmitic and acetic acids.By the action of alcoholic potash on a-bromostearic acid, Le Sueurobtains, together with a-hydroxystearic acid, an isomeride of oleic acidhaving the above constitution, which he designates as Aa-oleic acid.On oxidation with potassium permanganate, it yields first a dihydroxy-stearic acid, and, on further oxidation, palmitic acid.Pimelic acid, which has hitherto only been obtained syntheticallyby a comparatively tedious method, can be readily prepared from1 : 5-di-iodo- or dibromo-pentane ; by action of potassium cyanide, thecorresponding nitrile is obtained, and this, on saponification by hydro-chloric acid, gives a theoretical yield of pimelic acid ;Br*[CH,],*Br -+ NC*[CH,],*CN -+ C02H*[CH2],*C0,Et.Hsmonet * and Braun 5 have both obtained this result, workingonly on somewhat different lines.The latter starts with benzoyl-piperidine, which, by the action of phosphorus pentachloride (orpentabromide), is converted into a mixture of benzonitrile and ae-di-chloropentane, and this mixture may be used directly for the aboveBouveault, C‘ompt. wncl., 1904, 138, 1108.‘2 Atti R. Accnd. ,Sci. Yorino, 1904, 39, 552.Y’rans., 1904, 85, 1708. ‘ Cow@. w i t t l . , 1904, 139, 59. Ber., 1904, 37, 3588'12 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.synthesis, since the benzonitrile is easily removed by steam distilla-tion.With the exception of the tartaric acids, our knowledge of thedihydroxy-derivatives of acids of the succinic series has hithertobeen somewhat limited, and an interesting communication hasrecently been published by Rosenlew on the PE-dihy?rozyadipicacids. Two isomeric PE-dibromoadipic acids were prepared byAschan's method, and these, by the action of baryta water, were con-verted i n to the corresponding dihydroxy-acids.These two acidsmelt at 173' and 132' respectively, and are designated as the A- andB-forms. The A-acid, which is the inore soluble, appears t o be theexternally compensated or racemic form, and the B-acid the internallycompensated form.Considerable attention has of late been paid t o the alkyl derivativesof barbituric acid owing to their medicinal value as hypnotics.Fischer and Dilthey2 find that when urea is acted upon by diethyl-malonic acid in presence of phosphorus oxychloride, the result is notdiethylbarbituric acid, as might have been expected from the previousinvestigations of Thorne and of Grimaux ; instead of this, a ureide ofdiethylacet*ic acid is obtained, But if, on the other hand, the con-densation of the ester is effected with the agency of sodium ethoxide,the dialkylbarbituric acids can advantageously be prepared :Et,:C:(CO,Et), + (NH,),CO + NaOEt =The monoalkyl derivatives can similarly be obtaiued froin themonoalkylmalonic esters.Thiocarbamide, guanidine, and mononlkylcarbarnides behave similarlyt o carbamides, but the s-dialkylcarbamides do not.Dialkylbarbituricacids can be obtained by the action of carbamide on dialkylmaionylchlorides.For the preparation of methyl esters of certain acids, Werner andSeybold 3 recommend the interaction of dimethyl sulphate with thealkali metal salt of the acid.It is shown that this method (whichhad previously been employed in special cases by H. Meyer, H. vonLiebig, and others) is sometimes successful where the usual met hodof esterification with methyl alcohol cannot be applied.I n preparing esters by the action of sulphuric acid and alcohol,H. Meyer recommends that the acid should be dissolved in concen-Ber., 1904, 37, 2090.&r., 1904, 37, 3658.Aniialen; 1904, 335, 334. ' dfoantsh., 19c4, 23, 840ORGANIC CHEMTSTRY-ALIPHATIC DIVISION. 73trated sulphuric acid and an equivalent quantity of the alcohol added ;the mixture is then poured on to crystallised sodium carbonate.As an example of one of the typical reactions of Grignard's reagenton esters may be mentioned the recent work of Pogorielski,l who showsthat when ethyl succinate is acted on by magnesium methyl iodide,the glycol, OH*CMe,*CH,*CH,*CMe,*OH, can be obtained, the finalresult therefore consisting in the replacement of -CO,Et by *CMe,*OH.2Previously this glycol had been prepared by Zelinsky (1902) fromacetonylacetone, also by the action of magnesium methyl iodide, thefinal change in this case being represented by the replacement of the:CO groups by *C(OH)Ne in the usual way.The esters of hydroxy-acids behave in a similar way ; thus Frank-land and Twiss : have recently shown that by the action of magnesiumphenyl bromide on dimethyl tartrate a product is obtained which,after hydrolysis with dilute sulphuric acid, yields a tetraphenyl-erythritol, OH*C(C,H,),*CH(OH)*CH(OH)~C(C,H,),*OH, a compoundwhich is isomeric with benzoinpinacone,0 H*CH( C,H,) C( C,H,)(OH) C( C,H 5)( OH) CH( C,H,) *OH.A further study has recently been made by Collie4 of methylfluoride, a compound first obtained by him in 1889 by the action ofheat on tetramethylammonium fluoride.On subjecting this gas tothe electric spark in a glass tube over mercury, it is almost imme-diately decomposed into carbon, hydrogen, and hydrogen fluoride,4CH,F = 4C +.4H2 + 2H2F2.On continued sparking, a filament begins to grow from the negativeelectrode, finally bridging the gap to the positive electrode. Thisfilament proves to be pure silicon, evidently derived from the glass.Silicon fluoride is probably first formed, and is then reduced by thehydrogen.It has been shown by Willstatter and Pummerer, that ethylacetonedioxalate (which was obtained by Claisen in 1891 from acetoneand ethyl oxalate by action of sodium ethoxide) can exist in twodesmotropic forms.One of these melts a t 104", is colourless, has nodyeing properties, and appears to be the monoenolic form :CO,Et*CO*CH:C( OH).CH,*CO*CO,Et orC0,Et COO CH, CO CH : C( OH)*CO,E t.The second mDdification, which can be obtained from the first byJ. Buss. Phys. Chcm Soc., 1904, 36, 882.Coiiipare also the reactions involved in the synthesis of' terpineol by W. H.Y'rnns., 1904, 85, 1666. hid., 1318 I) Iier. 1904, 37, 3733.Perkin, jun., this vol., p.11774 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the action of alkalis, melts at 9S0, is lemon-yellow, and dyes wool adeep yellow colour.CO,Et*C(OH):CH*CO*CH:C(OH)*CO,Et.The latter compound is of particular interest, since it appears to bethe only known nitrogen-free member of the aliphatic series whichacts as a dye-stuff.B a s e s .It is apparently the di-enolic form :For the characterisation and estimation of amines, Sud borough andHibbertl propose to make use of Grignard’s reagent. Meunier2showed that with primary and secondary amines the reagent behavesin the following way :RNH, + CH,*MgI = RNH*MgI + CH,andRR,NH + CH,MgI = RR,N*MgI + CH,.The first-named authors find that this reaction with primaryamines takes pIace quantitatively in the cold, but that on heatinga second molecule of methane is liberated, probably according to theequation :RNK*MgI + CH,*MgI = RN(MgI), + CH,.I n the case of secondary amines, however, one molecule of methaneis given for each molecule of amine, even on heating, and with tertiaryamines no gas is evolved.Cadaverine or pentamethy lenediamine was synthetically preparedby Ladenburg in 1883-1886 by the reduction of trimethylenecyanide.A new synthesis of this base has now been effected byBrlzun in the following way : ac-dichloropentane is first preparedfrom yiperidine in the manner indicated on p. 71, and in order toreplace the halogen atoms by the amino-group, since the simple actionof ammonia does not give good results in this case, the method ofGabriel was employed.This consists in acting on the halogencompound with the potassium derivative of phthalimide, and decom-posing the resulting compound with hydrochloric acid. The changesinvolved are indicated in the following scheme ;C5Hlo:NH -+ C,HlON*CO*C,H5 -+ Cl(CHJ,Cl -+The cadaverine is a t once obtained, in the form of its sparinglysoluble hydrochloride, in a pure state, and the yield of the freeProc., 19d4, 20, 165,Ber , 1904, 37, 3583.Cotnpt. r e d . 2 1903, 136, 758ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 75base amounts to about 50 per cent. of the weight of piperidineemployed.Serine and isoserine, which are the a-amino-p-hydroxy- and p-amino-a-hydroxy-derivatives, respectively, of propionic acid, were syntheticallyprepared i n 1902 by Fischer and Leuchs ; serine was obtained fromglycollic aldehyde-ammonia and hydrogen cyanide, and isoserine fromP-chlorolactic acid and ammonia.isoSerine has now been synthesised in a different way by Ellinger,land by Neuberg and Silbermanna2 The method employed consistsin acting on the monohydrobromide of up-diaminopropionic acid inaqueous solution with silver nitrite, the mixture being kept a t about40' for 3 or 4 days.The principal change may be represented asfollows :NH,*CH,*CH(NH,)*CO,H,Hljr + AgNO, =NH,*CH,-CH(OH)*CO,H + AgBr + N, + €&OnThe two modifications of serine can be distinguished, as previouslyshown, by their phenylcarbimides, copper salts, and behaviour withnaphthalene-P-sulphonic chloride.The syntheses of cystein and of cystine have recently been accom-plished by E.Erlenmeyer, jun.,3 and it is shown that their constitutionis to be represented by the formulz CH,(SH)*CH(NH,).CO,H and[-S-CH,*CH(NH,)*CO,H], respectively. When the ethyl ester ofbenzoylserine, OH*CH,*CH[NH(CO*C,H,)]*CO,H, is acted on byphosphorus pentasnlphide, the hydroxylic oxygen is replaced bysulphur, giving the ester of benzoylcystein ; this, on hydrolysis, yieldscystein, and by oxidation of the latter, cystine is obtained.A new synthesis of r-leucine (r-a-aminoisohexoic acid) is describedby Bouveault and Locquin.4 It is effected by the reduction of ethyla-oximinoisobutylacetate, (CH,),CH*CH,*C(NOH)*CO,Et, with alu-minium amalgam in presence of ether.Leucinimide, which is thecorresponding diketopiperazine derivative (see p. 77), is obtained byspontaneous decomposition of the ethyl ester.An isomeride of leucine, which is described RS d-isoleucine, has beenobtained by Ehrlich 5 from the liquors to which the strontia-processhas been applied in the manufacture of beet-root sugar. This authoris of opinion that this isomeride nearly always occurs together withZ-leucine as a primary product in the hydrolysis of proteids. The factthat these two forms of leucine can give mixed crystals probablyexplains the difficulty which is sometimes experienced in isolatingBey., 1904, 37, 335.B d l . SOC. china., 1904, [iii], 31, 1180.Zeit. Yer. Dezbt. ZwkerCnd., 1903, 571, 809, and Be.'.., 1904, 37, 1809.Ibid., p.341. An.lznlen, 1904, 337, 23676 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ordinary I-leucine. The constitution of d-isoleucine is not fullyestablished, but it appears not improbable that it is the p-amino-acid.P o I yp e p t i d es.With the object of throwing further light on the nature of proteidsubstances, chemists have for some considerable time made attemptsto obtain condensation products from those amino-acids-such asglycine, leucine, and asparagine-which result from the hydrolyticdecomposition of proteids. As examples of some of the earlier attemptsi u this direction, one may refer to the formation of the so-called poly-aspartic anhydrides from asparagine and aspartic acid by Schaal(l871)and Schiff (1898), and the condensation of one of these anhydrides byGrimaux (1882).The product obtained in the latter case was acolloidal, gummy mass, which had many of the characters of a proteidand gave the “ biuret reaction ” with alkaline cupric oxide. Schutzen-berger ( 1888-1891) also prepared prokeid-like substances by heatingamino-acids with urea and phosphoric oxide. Lilienfeld (1894) actedon ethyl glycine with condensing agents, such as potassium hydrogensulphate or formaldehyde, and obtained a base which he called ‘‘ biuretdimethylene,” which had the percentage composition of gelatin,and which, when condensed with the esters of other amino-acids,gave products which exhibited some of the characters of proteids.But all of the above-mentioned products were amorphous, of un-known constitution, and generally difficult to identify a s singlesubstances. It is to Curtius and to Fischer-with the co-operationof their colleagues-that we are indebted for the systematic buildingup of complex compounds, the constitution of which is beyond doubt,from amino-acids in such a manner that the residues of these acidsare coupled together, link by link, into “ chains.”Such compounds may be regarded as being formed by the inter-action of the amino-group of one acid with the carboxylic hydroxyl ofthe next, a molecule of water being eliminated :NH,.R”. co :OH ““H~NH. w. CO,H.._............_..The names glycyl, leucyl, alangl, and so on, are given by Fischerto these NH,*R”*CO groups, which replace the hydrogen atom of thenext NH, group, and the complex chains so produced are called byhim “ polypeptides.”I n order to bring about this systematic linking, many entirelydifferent methods have been devised.Curtius, in 1881, by the actionof silver glycine on benzoyl chloride, obtained, in addition to otherproducts, hippurylglycine, that is, the benzoyl derivative of glycyl-glycine, C,H,*CO*NH.~H,*CO.NH.CH,.CO,H, and two years lateORGANIC CHEMISTRY-ALIPHATIC DIVISION. 77he showed that the ethyl ester of glycine undergoes spontaneousdecomposition, giving glycine anhydride and the so-called ‘( biuretbase.” He showed later that this glycine anhydride has thebimolecular formula, and its reactions indicate that its constitutionis to be represented asTH*CH,*YOCO*CH,*SH’or diketopiperazine.Fischer, in 1901, used this substance as the starting-point of hisresearches in the direction above indicated, and showed that when itwas heated for a short time with concentrated hydrochloric acid thepiperazine ring was broken and the hydrochloride of an amino-acidwas obtained.NH,*CH,.CO*NH*CH,*CO,H,the simplest example of *a dipeptide.The ester of this dipeptidereacts with ethyl chlorocarboaate, in presence of alkalis, to form thecarbethoxy -derivative, EtO- CO*NH* CH,* (70 NH* CH, C0,Et.By introduction of the carbethoxy-group in this way, the veryreactive amino-group is rendered more stable, and tl e ester of theresulting compound can now be made to condense with the esters ofother amino-acids by simple heating.In this way, Fiacher obtainedthe carbethoxy-derivative of diglycyl-leucine ester (a tripept id€derivative), EtO*CO*NH*CH,*CO*NH*CH2*CO*NH*CH( C,HJ-CO,Et.This method of building up longer chains has, however, its dis-advantages, since the condensation becomes more difficult as thehigher members are reached, and a new method has consequently beensought for. It was found that the acid chlorides of amino-acids couldbe prepared by means of thionyl chloride provided that the amino-group is first rendered stable by the introduction of carbethoxyl inthe manner stated above. The acid chloride so obtained can thenreact with the esters of other amino-acids to produce derivatives of thehigher members.Carbethoxyglycylglycine, for example, was in this way convertedinto the acid chloride, and this reacted with ethyl glycylglycine to give%t tetrapeptide derivative, EtO*CO(NH*CH,*CO),*NH*CH,*CO,Et(carbethoxytriglycine ester), and in a similar way the mixed dipeptidederivative, carbet hoxygl ycylalanine, was prepared.Notwithstanding the wide applicability of this method and thefacility with which the changes can be brought about, it could not besaid that the final object had been attained, since it is difficult or im-possible to obtain the free polypeptides from the carbethoxy-deriv-atives.Yet another method was therefore devised which has yieldedthe most excellent results, and is applicable for the synthesis of themost complex poljyeptides. It is evident thzt the limits of this syn-This amino-acid is in fact glycylglycine78 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.thetical process have not yet been reached in the compounds described ;the operations, in fact, appear to become easier and the yields betteras the compounds become more complex.Briefly stated, this new method consists in acting on the poly-peptide or its ester with a halogen-substituted acid chloride, and then,by the action of aqueous ammonia, replacing the halogen in the result-ing compound by the amino-group.The dipeptide, glycylglycine, for example, reacts with chloroacetylchloride to give chloroacetylglycylglycine, and this, when subjected tothe action of aqueous ammonia, even in the cold, gives the tripeptide,diglycylglycine :(NH,*CH,*CO)NH*CH,*CO,H ---+C1CH,~CO*(NH*CH,*CO)*NH*CH2*C0,H -+(NH,*CH,-CO)(NH*CH,* CO)NH*CH,*CO,H.This tripeptide can now react simiIarly with chloroacetyl chloride toproduce the chloroacetyl derivative, which, in its turn, is changed byammonia into the tetrapeptide, triglycylglycine,NH,*CH,*CO*[NH* CH,*CO],*NH*CH,*CO,H,and by exactly similar steps this tetrapeptide can be changed to thepentapeptide, tetraglycylglycine,NH,*CH,*CO*[NH*CH,*CO],*NH*CH,*CO,H.The dipeptides hit herto known, glycylglycine, alanylnlanine, andleucyl-leucine, were all obtained by the method first described, that is,by fission of the corresponding diketopiperazine ; for the prepara-tion, however, of mixed dipeptides, this method is not well adapted,since the piperazine derivatives are in’ such cases difficult t o obtain.By the new process, however, mixed polypeptides can be prepared ofapparently any degree of complexity. As examples of some of themixed forms which have recently been synthesised by Fischer and hiscolleagues, the following may be mentioned.i- Glyc ylalanine, (NH,.CH, CO) *NH * CH( CH,) CO,H, is obtained, bythe steps above mentioned, from chloroacetyl chloride and alanine,and glycyl-1-tyrosin, (NH,. CH,* CO) *NH-CH( CO,H)* CH,* C,H,*OH, isprepared similarly from I-tyrosine or its ester. The latter dipeptide iseasily soluble in water, gives Millon’s reaction, and can be hydrolysedby trypsin.From I-tyrosine and a-bromoisohexoyl chloride, Zeucyl-1-tyrosinecan be obtained, but only in the amorphous state ; the correspondinganhydride, C,HD*CH<~~~~>CH.CH,.C,H,-OH, however, crystal-lises in needles.It has been shown that a-pyrrolidinecnrboxylic acid (for which theshort name “ prolin ” is suggested) is a component of most proteiORGANIC CHEMISTRY-ALIPHATIC DIVISION.79substances, and it was therefore of especial interest to attempt thesynthesis of polypeptides in which the radicle of this acid is contained.A dipeptide of this nature has been prepared by acting on alanine witha&dibromovaleryl chloride, CH,Br*CH,.CH,*CHBr*CO~l, and de-composing the resulting as-dibromovalerylalanine with ammonia. Thedipeptide so obtained is called prolylalanine, its constitution beingCH,* CH,* CH,* CH*CO*NH*CH(CH,)* C0,H.\\ / /“H’I t crystallises in plates, is easily soluble in water, dissolves cupricoxide, forming a blue solution, and is precipitated by phosphotungsticacid.Up to this stage of the inquiry, only four halogen-substituted acidradicles had been employed in the synthesis of polypeptides by the newmethod, namely, chloroacetyl, bromopropionyl, a- bromoisohexoyl, anda8-dibromovaleryl.These serve for the introduction of glycyl, alanyl,leucyl, and prolyl respectively.With the object of introducing the radicle of phenylalanine, it wasnecessary to obtain the chloride of one of the a-halogen phenylpropionicacids; these cannot be prepared by the usual methods, but it wasfound possible to prepare indirectly a-bromo-/3-phenylpropionic acid,C,H5*CH,*CHBr*C0,H. This acid reacts with ammonia to givephenylalanine, and its chloride condenses with amino-acids in the usualway to produce the desired polypeptides.With glycylglycine, forexample, phenylalanylglycylglycine is obtained, and with phenylalanineit gives p h n y Zalany @hen y Za Zanine,[C,H,*CH,* CH( NH,)*CO]*NH*CH(CO,H)*CH,°C,H,.I n the latter case, however, the yield is small, and as a by-productthere is formed cinnamoylpl~ei~ ylalanine,( C6H5* CH: CH* C0)NH. CH( CO,H)*CH,*C,H,.I n addition to the above, the following are some of the mixed poly-peptides which have recently been obtained :Leucylprolin. Leucyl-a-leucylpheiiy lalanine.a- and P-Leucylphenylalanines. Diglycylphenylalanine.Alanylphen ylalanine. Leucylglycylphenylalanine .The researches of Morner (1901) have established the fact thatcystine is a regular component of sulphur-containing proteid sub-stances, and that its proportion may in certain cases amount to as muchas 12 per cent.of the total weight. It was therefore evidently highlyinteresting and important to ascertain whether it is possible t o syn-thesise polypeptides or analogous compounds by the coupling togetherof cystine with the amino-acids above referred to. Such compound80 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.may not improbably be formed in the successive building up and degra-dation of albuminous substances.I n the more recent experiments of Fischer and Suzuki, it is shownthat cystine readily reacts with halogen-substituted acid chlorides inalkaline solution, and when the products so obtained are treated withammonia the corresponding polypeptides result. I n these reactions, itis found that one molecule of cystine reacts with two molecules of theacid chloride.Diglycylcystine,(KH,*CH,*CO)NH*~H*CH,*S*S*CH,*~H*NH(CO*CH,*NH,),is prepared in the above manner from chloroacetyl chloride and cystine.It is a colourless, hard, transparent substance which does not crystal-lise, is easily soluble in water, and its solution dissolves cupric oxide,giving a blue solution.Dinlccnylcystine is similarly obtained from cystine and a- bromo-propionyl bromide.The pure product is sparingly soluble, crystallisesin microscopic prisms, and is lavorotatory.Dileucylcystine is obtained in like manner from cystine and a-bromo-isohexoyl chloride. It is fairly easily soluble in cold water and has notbeen crystallised. The aqueous solution, on evaporation, leaves aglassy residue which, when rubbed, is changed to a colourlesspowder.Further, it appeared desirable to attempt the synthesis of poly-peptides in which the residues of asparagine or aspartic acid arecontained, since, from previous observations, there is little doubtthat the latter substances exist in natural proteids in the form ofpolypeptide-like compounds.Fischer and Koenigs hare found t h a tasparagine (and aspartic acids) react with halogen-containing acidchlorides in the usual way, and from the coinpounds so obtained, byaction of ammonia, polypeptides are obtained in which a monobasicacid group replaces hydrogen in the amino-group of asparagine.Glycylccsparugine, (NH,*CH,*CO)*NH*CH(C0,H)*CH2*CO*NH, andleucy lasparagine,[ (CH,),CH* CH,*CH(NH,) CO]*NH.CH( CO,H)*CH,* CONH,,were in this manner obtained from I-asparagine and chloroacetyl andbromoisohexoyl chlorides respectively.I n ordert o obtain polypeptides in which the acid radicle of aspartic acidreplaces hydrogen in the amino-group of other amino-acids, chloro-or bromosuccinyl chloride was made to act on an alkaline solu-tion of the amino-acid or its ester.In this case, the resultinghalogen-containing product does not act directly in the usual way withammonia, but gives a fumaryl derivative; the latter, however, by theC0,H C0,HBoth of these polypeptides give a strong biuret reactionORGANlC CHEMISTRY-ALIPHATIC DIVISION.81action of ammonia at a higher temperature, is transformed into theaspartyl derivative.Chlorosnccinyldialanine, for example, gives fnmaryldialanine, and thelatter, when heated to 100" with aqueous ammonia, is changed to therequired polypeptide, as~artyZdicclarzi~,ae,[ CO,H* CH( CH,)NH] CO* CH,. CH(NH,)* CO[NH*CH( CH,) CO,H].These fumaryl derivatives can be ob-tniued without first preparing thehalogen-substituted succinyl chloride ; it is sufficient to act withfumaryl chloride on the ester of the amino-acid, and then saponify theresulting product.All the results above mentioned tend strongly to confirin theconviction that there is n close resemblance in properties between theseartificial polypeptides and the n;kturnl peptones ; this similarity isespecially marked in the case of mixed polypeptides and particularlyso in their amides.Amongst some of the reactions in common maybe mentioned their precipitation with phosphotungstic acid, theproduction of the (' biuret " reaction with alkaline cupric oxide, and thecapability which many of them possess of being hydrolysed by trypsin.Under the influence of the latter ferment, glycyl-Z-tyrosine yields glycineand Z-tyrosine, and racemic leucylalanine gives leucyl-d-alanine and anactive clipeptide which appears to be leucyl-Z-alanine.The principal researches of Fischer and his colleagues on the poly-peptides will be found in the following papers : Ber., 1901, 34, 2868 ;1902, 35, 1095 ; 1903, 36, 2094, 2106, 2592, 2982; 1904, 37, 2486,2842, 3062, 3071, 3103, 3306, 4575, 4585.The derivatives of several of the above-mentioned polypeptides hadbeen obtained previously by Curtius, although in some cases their truenature has only recently been established.I n the year 1881, heshowed that by the action of benzoyl chloride on silver glycine threenitrogen-containing acids were formed; one of these proved to behippuric acid, identical with the natural product, and the others hecalled the p- and y-acids. The /3-product was later shown to be thebenzoyl derivative OF glycylglycine, as above mentioned. The y-acidhas recently been further examined by Curtins and Benrath,l and isshown to be the benzoyl derivative of pentaglycylglycine,C6H,*C'O-[NH*CH2* CO],*NH*CH,*C02H,that is to say, a hexapepticle derivative.It may also be prepared byfusing ethyl hippurate with glycine, or its ester may be obtained fromthe azoimide of benzoyltriglycylaminoacetic acid.These berizoyl derivatives of polypeptides may be built up link bylink by the action of hippurylazoimide on various amino-acids, such asglycine, glycy lglycine, aspartic acid, p-aminobutyric acid, h e ,It was stated above that the ethyl ester of glycine undergoesVOL. 1. G1 Rer., 1904, 37, 127982 ANNUAL REPOKl’S ON THE PROGRESS OF CHEMISTRY.spontaneous decomposition giving glycine anhydride and the ‘‘ biuretbase.” This change has now been more minutely examined, and it isfound that if moisture is excluded the product consists almost entirelyof the biuret base, and that the proportion of glycine anhydrideincreases as more moisture has accessal This biuret base has also beenfurther investigated; Schwarzschild considered it to be the ester ofhexaglycylglycine, but Curtius now shows that it is a tetrapeptidederivative, namely, the ethyl ester of triglycylglycine,NH,* CH,*CO*[ NHCH,CO],*NH* CH,* (30,.C,H5.This base is easily soluble in water and gives many reactionscharacteristic of proteids. It gives the biiiret reaction and producesprecipitates with phosphomolybdic acid, tannic acid, lead acetate, &c.Schwarzschild bas previously shown2 t h a t when this base has beenSubjected to the action of trypsin for 4-6 days it no longer gives anybiuret reaction.Analyticul Processes.The two following processes are described in the report on analyticalchemistry.(i) The rapid ultimate analysis of certain carbon compounds$(p.156).(ii) The determination of methyl alcohol in presence of ethylalcohol * (p. 166).A new and simple method for the determination of acetyl groups isgiven by A. G. Perkin.5 The substance to be examined is distilled withalcohol and sulphuric acid, and the resulting ethyl acetate is collectedi n standard alcoholic potash and determined by titration.For the determination of hydroxyl groups in organic compounds,Tschugaeff, in 1902, proposed a method based on the estimation of theamount of methane evolved when the compound is acted on inethereal solution by magnesium methyl iodide, according to therelationROH + CII,*MgI = RO*RfgI + CH,.Hibbert and Sudborough have carefully examined this method andfind that, in order to obtain reliable results, it is advisable to use amylether as solvent in place of ethyl ether, and to carry out the operationsin an atmosphere of nitrogen.6Pringsheim and von Konek * recommend the use of sodium peroxideCurtius, Ber., 1904, 37, 1284.Beitr. chem. PhysioZ. Path., 1903, 4, 165.Collie, Tmns., 1904, 85, 1111.Thorpe and Holmes, ibid., 1.Proc., 1904, 20, 171.Ber., 1904, 37, 2155.Zeit. angew. Chew., 1904, 17, S86.Tmm., 1904, 85, 933ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 83for the detection and estimation of halogens, phosphorus, arsenic, andsulphur in organic compounds. For this purpose, it is recommendedthat the peroxide should be mixed with about 25 times its weight ofsome substance rich in carbon and hydrogen which is not hygroscopic,such as naphthalene or cinnamic acid; this mixture can then be storedready for use in a closed flask. Even carbon may be estimated,according to von Konek, by determining the amount of carbonateformed when the organic substance is oxidised with sodium peroxide.For the dehydration and preservation of ethyl alcohol, Evans andFetsch 1 suggest the use of magnesium amalgam, which is easily obtainedby rubbing together mercury and powdered magnesium, the latterbeing added gradually. This amalgam is without action on coldabsolute ethyl alcohol, but reacts instantly with water. When heatedwith methyl or ethyl alcohols, the corresponding magnesium methoxideor ethoxide are produced, the former being soluble and separating inthe crystalline form on cooling.The conditions under which the '' pyrrole reaction " is given by varioussubstances, may, according to Neuberg,2 afford useful information fortheir identification.He divides the substances under consideration into four classes :(1) those which give the reaction directly (pyrrole, indole, carbazole) ;(2) nitrogen-containing substances which, when decomposed by heating,give off vapours capable of showing the reaction (certain amino-acidsand ammonium salts, such as glutamic acid, cystine, serine, taurine,ammonium malate and pyruvate, be.) ; (3) nitrogen-containing substanceswhich yield the reaction only when heated with zinc dust (glucosamine,glucose-oxime, erythrose diacetamide, and ammonium salts of gluconic,tartaric, oxalic, and malonic acids) ; (4) nitrogen-free oxygen-containing substances which give pyrrole when heated with ammoniaor ammonium salts (y-diketones).H. J. H. FENTON.J. Amr. C'hcm. S'uc., 1904, 26, 1158.C h m . Ccntr., 1904, ii, 1435.G

ISSN:0365-6217    

DOI:10.1039/AR9040100055

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

ORGANJC CHEMISTRY-AROMATIC AND OTHER CYCLICDIVISIONS.IN reviewing the year's work in so wide, varied, and fertile a field ofresearch as that of the chemistry of the aromatic compounds, it is adificult task to indicate which region has yielded the most abundantor the most luxuriant harvest. The ground most assiduously cultivatedis naturally that which is related to the industries based on organicchemistry.Although the development in the field of colour chemistry hasfollowed the old lines, there has been no diminution in the crop of newdye-stuffs. On the theoretical side, the study of the relation of colourto structure, always a fascinating subject for speculation, ha-, receivedmore than its usual share of attention, and appears rather to growthan to diminish in complexity.Whilst a strong case has been madeout for the existence of a quinonoid ion in members of the triphenyl-methane and allied dyes, the total absence of colour in the quinone-imines and the existence of true dye-stuffs with an open chainstructure is opposed to any general application of a quinone structureto every class of colouring matters.I n the region of synthetical chemistry, a powerful stimulus has beenoffered by the elaboration of new reactions as well as by the modifica-tion of old ones. I n the latter case, the tendency lies in the directionof milder reagents. Given a corupound in a labile state, a catalyst ofthe most insipid kind may prove a powerful instrument of chemicalchange. The lability of vital products is the priinum movem of theirrapid and complex evolutions under conditions which might seein toexclude chemical agency altogether.'I'he conductivity of mineral acids in ehhereal solution touches thefringe of important applications of physical chemistry to organicreactions, which promise an interesting development.The unique character of Gomberg's tervalent carbon compound,taken in conjunction with the signi6cance of its double molecularformula, clernancl for the present an open verdict on its structure untilfurther evidence is forthcoming.The subjects of the report have been grouped in sections so as topermit of general treatment and scarcely require explanationORGANIC CHEMISTRY-CYCLIC DIVISIONS.85New Reagents.The use of dimethyl sulphate as a methylating agent, which was intro-duced by Ullmann,l and has proved so serviceable in preparing methylderivatives of hydroxy- and amino-compounds and of sulphonic acids,can also be used in the preparation of methyl esters from acids wherethe usual met hods fail.2The well-known Schotten-Baumann method of acylating, i n whichthe acid chloride is used in presence of alkali, can be modified withadvantage in many cases by replacing the alkali by pyridine. Themodified reaction has been widely applied3 Recent papers on the sub-ject by Freundler4 deal with the acylation of alcohols and amino-com-pounds, whilst Auwers 5 has shown that hydroxy-compounds withbasic substituents like the hydroxybenzylarylaminss (I) and aromatichydroxyaldehydephenylhydrazones (11) produce, in presence of pyridine,O-esters, when under ordinary circumstances N-esters would beformed :./OAc 0-4cCGH4<CH,*NHAr C6H4<CH:N *NH* cp;I.11.Heller finds, moreover, that acylated compounds containing thegroup N*CN, which are usually unstable when alkalis are used, canbe readily obtained with pyridine.The substitution of ammonia for the caustic alkalis and alkyl oxides,which bears a certain analogy to the above, is dealt with under “ con-densation ’’ on p. 98.The action of potassium cyanide on aromatic nitro-compoundsproduces a very complex series of changes which have been ex-haustively studied by Lobry de Bruyn.7 The action may be of athree-fold character. The cyanide may act as a reducing agent andform azo-, azoxy-, nitroso-, and amino-compounds, or, if the reactionproceeds in alcoholic solution, the replacement of a nitro-group byan alkyloxy-group may occur, or, thirdly, one or more cyanogengroups may enter the nucleus whereby either a nitro-group orhydrogen is replaced.Iu an interesting series of memoirs on aaimilar subject, namely, the action of potassium cyanide on nitro-phenols, the constitution of the purpuric acids is discussed by BorscheAnnalen, 1903, 327, 104.2 Werner a i d Seybold, L’er., 1904, 37, 3655 ; H. von Liebig, Ber., 1904, 37,3 Einhorn and Hollandt, Annalen, 1898, 301, 96.4 Bull. SOC. chim., 1904, [iiij, 31, 616, 621.0 Ber., 1904, 37, 3899.4036.Ibid., 3112. Rec. Trav. chim., 1904, 23, 2686 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.and Locatelli and Borsche and Bocker.1 The papers are too long toreview, but it may be stated that here also cyanogen appears to enterthe nucleus and that a nitro-group undergoes reduction to a hydroxyl-amine group.A curious reaction of potassium cyanide has been observed by Wolffand Lindenhayn in connection with diazoacetophenone and diazo-benzeneimide.With the former a salt of acetophenoneazocyanide, andwith t,he latter phenylcyanotriazine, is formed :Acetophenoneazocy anide.Phenylcyanotriazine .The use of potassium cyanide in the formation of additive com-pounds, to which this reaction strictly belongs, is referred to again onTon Brann 3 uses cganogen bromide for preparing cyanobenzenesul-phonamides by adding the reagent to the sodium compound of thesulphonamide.Benzenesulphonanilide gives C,H,*SO,(N*C,H,)*CN.The same reagent is used for obtaining a new class of dyes, whichpromise to be of some importance (p. 128).The action of nitriles on carboxylic acids, which was first studied byGautier, has been very fully investigated by Konig4 The reaction takesplace in the following way :p. 102.R*CiN + HOaC0.R’ -+ R*Y:N*CO*R’ -+ R*CO*NH*CO*R’.OHAnthranilic acid also combines with nitriles, but forms a t the sametime a quinazoline derivative by inner condensation. Very importantfrom a technical, as well as a theoretical, standpoint is the action of thealkali sulphites on aromatic amino- and hydroxy-compounds, whichforms the subject of a series of papers by Bucherer.5 The reactionmay be divided into the following three categories.1.By the action of bisulphite solutions on aromatic amino-compoundsthe latter lose ammonia and are converted into new substances, which,on hydrolysis, break up into the corresponding aromatic hydroxyl com-pounds and sulphurous acid, which is eliminated. The intermediateRcr., 1902, 35, 569; 1904, 37, 1843, 4388.lbid., 1904, 37, 2374.J. pr. Chenz., 1904, [ii], 69, 1.lbid., 2809.5 Ibid., 49 ; 70, 345 ; Zeil. Farb. Text. Ind., 1904, 3, 57ORGANIC CHEMISTRY-CYCLIC DIVISIONS. 87compound may consequently be regarded as the sulphurous ester ofthe hydroxyl compound :R*NH, + 2NaS0,H = R.O*SO,H + Na2S0, + NB3.2. Hisulphite solutions convert aromatic hydroxyl conipounda intothe above sulphurous esters :R*OH + 2NaS03H = R*O-SO,H + Na,SO, $; H,O.3.Ammonium sulphite solution in presence of ammonia convertsaromatic hy droxyl compounds into the corresponding amino-compounds,a process whichis probably determined by the formation of the inter-mediate sulphurous ester above referred to. The reaction can beexpressed by the following equation :R*OH + (NH,),SO, + NH3 = R*NH, + (N€X,),SO, + H,O.It should be added that the sulphites of aliphatic amino- andhydroxy-compounds do not react as above described, and, moreover,the benzene derivatives shorn less reactivity than those of naphtha-lene. The reaction appears to depend on the stability of the sulphur-ous ester, which is affected not only by the character, but also by thesubstituents of the nucleus.The position of the sulphonyl group inthe sulphonic acids, for example, has a marked influence, sometimesretarding, a t others assisting the reaction, A number of experimentaldetails are given showing the conversion of naphthylamine and itssulphonic acids into the corresponding naphthol compounds andthe reverse change f rom naphthols into naphthylamine derivatives.It appears, moreover, that by acting on P-naphthol and /3-naphthyl-amine and their derivatives with aromatic amino-compounds in presenceof bisulphite they pass into secondary or aryl-substituted P-naphthyl-amines, forming, as before, sulphurous esters as intermediate productsin the following way:I, RP-OH + HO*SO,Na = R*O*SO,Na + H,Oor RP*NH, + HO*SO,Na = R*O*SO,Na + NH, ;11, H,NR + R*O*SO,Na = R*NHR + NaHSO,.Metals and metallic compounds are coming more and more into useRS organic reagents, acting, as a rule, the part of catalysts.The use ofmetals as “ halogen carriers ” and of copper in Sandmeyer’s reactionare too well known to need description. Ullmann and his colla-borators * have recently shown that finely-divided copper may be usedfor removing halogens from the nucleus of aromatic compounds. Thehalogen, which is usually regarded as so firmly attached as to defy theattack of most reagents, may by this means be simply removed or sub-Ber., 1903, 36, 2383 ; 1904, 37, 853 ; A m c d e i i , 1904, 332, 3888 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.stituted by amino- and phenoxyl groups.Good yields of diphenyl (and itsderivatives) have been obtained from iodobenzene (and its derivatives)by heating the substances-with copper in a fine state of division to210--320°, either in closed or, if the boiling point is high enough, inopen vessels. A technical application of this discovery is the subjectof a patent for the preparation of anthranilic acid and derivatives fromo-chlorobenzoic acid and the amines in presence of copper. The use offinely-divided nickel as a reducing agent is described on p. 93.Dewar and Jones1 have found that nickel carbonyl acts on benzenein presence of aluminium chloride and converts it, at the ordinarytemperature, mainly into benzaldehyde. At 100’ the principal productis anthracene.Eijkman 2 has utilised Friedel and Crafts’ method for the synthesisof aromatic acids from lactones.For example, y-methylbutyrolactonewith benzene and aluminium chloride yields phenyl-y-methylbutyricacid, C,H,* C( CH3)*CH,*CH,* C0,H. Another interesting applicationof the same reaction is the preparation of benzeneazodiphenyl,C,H,*N, C6H4*C6H5, and its homologues by the action of aluminiumchloride on a mixture of azoxybenzene (or its homologues) and thearomatic hydr~carbon.~Grignurd’s Reaction.-The importance of Grignard’s reaction as aninvaluable aid to organic synthesis has become more emphasised withfurther study, and no less than fifty separate investigations in connectionwith the aromatic compounds alone have appeared during the presentyear. Of these, Grignard4 has contributed one on the preparation oftertiary alcohols from esters.The compound R*CO*OMgX is firstprepared in the usual way, and a second molecule, R’MgX, is then addedin the cold. The mixture is heated on the water-bath and ultimatelydecomposed with dilute sulphuric acid, when the tertiary alcoholCRR’*OH is formed according to the following equation :Other aromatic hydrocarbons behave similarly.R*CO*OMgX + R’MgX = CRR(OMgX),.CRR’(OMgX), + R’MgX = CRR,’OMgX + (MgX),O.Phenyldiethylcarbinol and diphenylethylcarbinol have been obtainedin this way.A number of papers5 which describe the formation of aromaticsecondary and tertiary alcohols from aldehydes and ketones affordlittle novelty except in the application of the method, but the newcarbinol derivatives containing a naphthalene, anthracene, or acridineTrans., 1904, 85, 212.Chcm. TVeekblncZ, 1904, 1, 421.Anz, Bull. Acnd. Sei. Cracow, 1904, 158.4 Compt. rend., 1904, 138, 15’1.6 Acree, Ber., 1904, 37, 990 ; Bistrzycki and Gyr, Ber., 1904, 37, 1245 ; Konow-doff, J. Rum, Pity8, Chem. Xoc., 1904, 36, 228 ; Mameli, &wetta, 1904, 34, [i], 358ORGANIC CHEMISTRY-CYCLlC DIVISIONS. 89nucleus are sufficiently rare to merit a short description. Magnesiuma-naphthyl bromide, CloE7MgBr, and benzophenone yield diphenyl-a-naphthylcarbinol, C10H7*C(C6H5)p*OH ; this, like the other triaryl-carbinols, is colourless, but becomes deeply coloured' (greenish-blue) byadding strong sulphuric acid or acetic and hydrochloric acids (see p.129).On reduction with tin and hydrochloric acid, it is converted liketriphenylcarbinol into the corresponding methane derivative.1 Anthra-quinone and magnesium phenyl bromide form y-dihydroxy-y-diphenyl-hydroanthrncenes :CLIH4<g$g{>c6H4.Diphenylanthrone (1) and magnesium phenyl bromide give in thesame way y-triphenyl-y-hydroxydihydroanthracene (11) : 3The formation of a hydroxydibydro-base from N-methylacridonebelongs to the same class of reactions. Magnesium phenyl bromideconverts N-met hylacridone (111) into hydroxyphen y l-N-met hyldihydro-acridine (IV) : *C6H4<NMe>C6H4 CO- '6=4<-NMe-- CPh(oH)>C 6 H 4'111. IV.Dialkylphthalides are readily obtained by the action of magnesiumalkyl compounds on phthalic anhydride. Dimethyl- and diethyl-phthalides have been prepared in this way :C,H*<-CO_>o' c(c=3)2Dime thylphthalide.Lactones behave similarly.6 Phthalimide, however, gives a some whatdifferent result and yields derivatives of phthalimidine as follows :C6H4<CO>NH co + 2C2H5*MgBr =cO<$~~~>C(C,H,)*OMgBr + C2H,.CO<$~~~>C(C,H,)*OMgBr + H,O =CO<3Ej>C:CH*CH3 + MgBrs + Mg(OH),.Acree, Be?.., 1904, 37, 616, 625, 2753.2 Haller and Guyot, Compt.rend., 1904, 138, 32%3 Haller and Guyot, ibid., 139, 9.4 Bunzly and Decker, Ber., 1904, 37, 575.7 BQis, Compt. Tend., 1904, 138, 987 ; 139, 61,Bauer, ibid., 735. Houben, ibid., 48990 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Magnesium phenyl bromide gives the phenylcarbinol compound :CO<$Ej>CPh* OH,The alkylsaccharins, which belong to the same group of substancesas the phthalimides, yield similar products.' Unsaturated compounds, assecondary products caused by the removal of water from the originalcarbinol, have been obtained by Hell and Bauer, Klagea, and othersby the help of this reaction.Anisylphenylketone and magnesium ethyl iodide give anisylphenyl-propylene, CH,*O*C),H,*C(C'6H5): c'H*CH,.So also anisaldehyde andmagnesium benzyl bromide give directly p-methoxystilbene without theformation of carbinol, whereas acetophenone and magnesium benzylbromide form phenyl benzylmeth ylcar binol,C,H,* C H,* C (OH) CH,* C,H,,which, only aFter heating with acetic anhydride, passes into a-methyl-s t ilb ene ,As these unsaturated hydrocarbons can be reduced with sodium andalcohol, the reaction affords a simple method for preparing aryl para&ns.3Schroeter and also Tiff eneau have utilised Grignard's reaction for pre-paring unsaturated acids.Acetophenone and ethyl iodoacetate inpresence of magnesium give the ester of hydroxy-acid which, on distilla-tion under the ordinary pressure, is converted into P-methylcinnamicacid.4R*C(CH3):CH,,have been obtained from the corresponding esters by using excess ofmagnesium methyl iodide in the following way :Unsaturated phenols with a pseudoallyl side-chain,CR(CH,),*OMgT + Mg(CHJ1 = CR(CH,):CH, + MgI, + MgO + CH,.The action of ethyl orthoformate on the organomagnesium compoundhas been employed in the synthesis of acetals and indirectly of aldehydesof the aromatic series,6HC(OR), + R'MgI = R'CH(OR), + RO*MgT.Sabatier and Mailhe 7 have prepared from cyclohexanone a series oftertiary alcohols having the general formula :1 Sachs, Wolff, and Ludwig, Ber., 1904, 37, 3252.2 Hell and Stockmayer, ibid., 225 ; Hell and Bauer, ibid., 230, 453, 1429,3 Klages and Heilmann, ibid., 1447.4 Tiffeneau, Compt.rend., 1904, 138, 985 : Schroeter, Ber., 1904, 37, 1090.6 Bodroux, ibid., 138, 92, 700 ; Tschitschibabin, Bev., 1904, 37, 186, 850.7 Comnpt. rend., 1904, 138, 139, 343, 1321.BQhal and Tiffeneau, Compt. rend., 1904,139, 139ORGANIC CHEMISTRP-CY CLIC DIVISIOKS. 91/\OH RThe introduction of alkyl groups into hydrocyclic compounds byGrignard's method has also been successfully employed by Perkin inthe synthesis of terpin, terpineol, and dipentene, to which reference ismade on p.11 3.The formation of glycols and pinacones has also been effected by thisreactioii.Acree has prepared benzpinacone, (C,H,),C(OH)*C( OH)(C,H,),, fromphenylbenzoin and magnesium phenyl bromide, as well as from benzil ormethyl benzilate and magnesium phenyl bromide. Benzoin or methylmandelate produce in the same way asp-triphenylethylene glycol,(C6H5)2C(OH) CH(0H) * C,H,.lDilthey and Last 2 have also obtained benzpinacone irom magnesiumphenyl bromide and ethyl oxalate.An interesting synthesis of an optically active alcohol has beeneffected by Frankland and Twiss by the action of magnesium phenylbromide on dimethyl tartrate.3 The aa88-tetraphenylerythritol whichis formed has a specific rotation of [ C Z ] ~ + 1 8 2 - 8 O .Finally, K i p ~ i n g , ~ Dilthey and Eduardoff ,5 Pfeiff er and Schnurmannand Truskeier 6 have shown that Grignard's reaction may be employedin the preparation of aryl and alkyl compounds of silicon and themetals.0 x id is i n g A gents.I n former papers, Harries has shown that by means of ozonealcohols may be oxidised to aldehydes, iodobenzene to iodosobenzene, andunsaturated compounds may be ruptured a t the double bond and con-verted into aldehydes and ketones.If, however, the ozone is allowedto react in a non-dissociating solvent, oxygen is added at the doublebond with the formation of compounds having the following formuh :>c:c< + 0, = >g-y< op >y-c.'<0.0.0 0-0These ozonides are decomposed with water into two molecules ofBer., 1904, 37, 2753.Ibid., 3775.Trans., 1904, 85, 1666.Ber., 1904, 37, 1139.Proc., 1904, 20, 15.l b i d . , 319, 112592 ANNUAL REPORTS Oh’ THE PROGRESS OF CHEMISTRY.ketone and hydrogen peroxide. The same result is produced by theaction of ozone on the unsaturated compound in presence of water. Theozonides are viscid, colourless, or light green oils, with a suffocatingsmell. The ozonides of mesityl oxide and acrolein are highly explosive,whilst those of the unsaturated hydrocarbons are, on the other hand,more stable and only explode on heating on platinum foil. The ozonidespossess the curious property of emitting rays which act more stronglyon the photographic plate than ozone itse1f.l Harries and his collabor-ators have used ozone for determining the position of the double bondin unsaturated hydrocarbons, and have employed it with advantage inbreaking down the caoutchouc molecule into simpler constituents.3More recently, Harries and Weiss4 have succeeded in analysingRenard’s ozobenzene, which the latter obtained by the action of ozoneon benzene.The compound is benzenetriozonide, to which Harriesassigns the followiug formula :o=o/ \I1CH ,O\ / I I o=oIt is obtained by passing a current of oxygen containing 5 per cent.of ozone for 1-2 hours into pure benzene. A gelatinous, opalescentproduct is formed, which, on removing the benzene, remains as a white,amorphous substance.It explodes violently when warm water ispoured upon it ; but when carefully warmed with water, i t passes slowlyinto solution as glyoxal.The oxidising action of fuming sulphuric acid in presence of mercury,which is used in the production of phthalic acid from naphthalene, is thesubject of two patents, one for oxidising anthracene to anthraquinoneand the other for converting an thraquinone-P-sulphonic acid into anew polyhydroxyanthraquinonesulphonic acid.Electrolytic methods both for oxidation and reduction are rapidlygaining in importance. The oxidation of anthracene and naphthalenet o the quinones has been effected by electrolysis in an acid solutioncontaining cerium salts, and A.G. and F. M. Perkin describe anelectrolytic method for producing purpurogallin from pyrogallol and itscarboxylic acid from gallic acid.1 B ~ T . , 1904, 37, 839.Ibid., 2708.Trans., 1904, 85, 243.Ibid., 842.Ibid., 3431ORGANIC CHEMISTRY-CYCLIC DIVISIONS. 93Beduction.-Two patents connected with electrolytic reduction havebeen applied for in the course of the year, one for converting nitro-benzene into paminophenol in the manner described by Gattermann,and the otber for the production of aromatic and aliphatic amino-basesby the electrolysis of an aldehyde in presence of ammonia or an amine.For example, f ormaldeh ydeaniline yields on electrolysis methylaniline ;acetaldehyde and ethylamine are converted into diethylamine.Electrolytic methods for the reduction of aliphatic and aromatic acidsand esters are described by Tafel and Friedrichs 1 and C.Meti;ler.2 Thereducing action of nickel in presence of hydrogen, introduced recentlyby Sabatier and Senderens 3 and used by them for the reduction of avariety of aliphatic compounds, has during the past year been success-fully applied to the preparation of cyclohexanols from phenols andcyclohexylamines from aromatic bases. By passing phenol vnpourmixed with excess of hydrogen over nickel at 215-230°, the phenol isreduced to cyclohexanol, which is at the same time partly convertedinto cyclohexanone by the loss of hydrogen. The mixed product may beeither wholly converted into alcohol by passing it a second time overnickel with excess of hydrogen a t a lower temperature (140 -l5Oo), orinto the ketone by conducting the vapour without hydrogen overcopper heated to 330’.Other cyclohexanols have been prepared byBrunel4 by this method. The new hydrocyclic alcohols are colourlessliquids with characteristic odours : cyclohexanol boils at 160-1 6I n the same way, when aniline vapour and hydrogen are passed overfinely-divided nickel heated to 1 90°, a mixture of nearly eqnal parts ofcyclohexylamine, C6Hll*NH2, dicyclohexylamine, C6Hl,*NH*C6Hll, andcyclobexylaniline, C6H5*NH*C,H,,, are formed ; cyclohexylamine is acolourless liquid with an ammoniacal smell resembling conicine ;it is a strong base which absorbs carbon dioxide from the air and formscrystalline salts. The xlkylanilines and m-toluidine have been reducedin the same way.Godcot has converted anthracene by Sabatier and Senderens’ methodinto tetrahydro- and octohydro-anthracenes.Acree has found a new method for reducing triphenylcarbinol andtriphenylchloromethane and their homologues to the me thane hydro-carbons without the formation of hexaphenylethane. Triphenylmethyl(see p.105), which is probably first liberated, very readily polymerisesin presence of hydrochloric acid to hexaphenylethane ; but by usingspongy tin and gradually adding the calculated amount of hydrochloric:wid, polymerisation is avoided and the reduction proceeds smoothly.Ber., 1904, 37, 3187.Conyt. rend., 1904,137, 1025 ; 138, 457, 1257.Holleman, Proc. h’. Aknd. Wetensch. Anzsterdana, 1903, 201.Compt.reizd., 1904, 139, 604.Ibicl., 3692.Ibid., 137,1268.BPr., 1904, 37, 81194 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ChZorincction.--Von Braun has succeeded in obtaining amidochloridesfrom aromatic amides by the action of phosphorus pentachloride inchloroform or other suitable solvent, from which the new substancemay be precipitated with light petroleum :R,CO*NR2 + PCI, = R,C(Cl,)NR, + POC1,.Ainidines can be obtained from them by the action of arylamino-compounds in the ordinary way. Dimet hylbenzamide, for example,gives the dichloride, C,H,*CCl,*N (CH3)2, which. with aniline, is trans-formed into the amidine, C,H,*C(N*C,H,)*N(CH,),. Now the dichloridesare unstable a t high temperatures and lose alkyl chloride, as von Pech-mann first pointed out, so that if dimethylbenzamide is heated withphosphorus pentachloride, methyl chloride escapes and methylbenzimido-chloride, C,H,*CCl:N*CH,, is produced.A t a still higher teinperatiire,a second molecule of methyl chloride is driven off, and benzonitrilefinally remains. The application of this reaction to acyl derivatives ofcyclic amines has led to interesting results ; for, under certain conditions,the ring opens and aliphatic products are formed. Benzoylpiperidine(I) with phosphorus pentachloride is either decomposed into benzimido-chloride of e-chloroamylamine (II), which readily changes into benzoyl-echloroamylamine (111), or it produces a mixture of benzonitrileand 1 : 5-dichloropentane (IV). 1 : 5-Dibromopentane can be obtainedin a similar manner :-+ U,H,*CO*NH(CH2),Cl or (CHJ5C12111.IV.I n a later paper, von Braun shows how piperidiae may be convertedinto pentamethylenediamine and pimelic acid by nieans of this reaction.Alkali hypochlorites as chlorinating agents have been applied by Chatta-way t o the preparation of nitrogen chlorides of the general formulaR*SO,*NCl,, and chloroamides of the formula R,*S0,*NC1*R,.2A curious process of chlorination by substitution is describedby Schmidt and Ladner.s WheE 9 : 1 O-bromonitrophenanthrene oro-bromonitrobenzene is heated in sealed tubes to 320' with ammoniumchloride, both bromine atom and nitro-group are replaced by chlorine,and satisfactory yields of the dichloro-compounds are obtained :B e y ., 1904, 37, 2678, 2812, 2915, 3210, 3583, 3588.Trans., 1904, 85, 971.Ber., 1904, 37, 4402ORGANIC CHEMISTRY-CYCLIC DIVISIONS. 95Br NO, c1 c1/-\/-\-/-\,/-\/-\,-/-\ -+ \-/ \-/ \-/ \-/Br NO, c1 c1/-\\-/ ' c-> -+\-The product formed by the chlorination of salicylaldehyde isheptachloroketotetrahydrobenzene :Cl,Biltz and Giesel find that on redudion with stannous chloride andhydrochloric acid a quantitative yield of tetrachlorophenol is obtained.By boiling the same product with dilute acetone, 90 per cent. of purepentachlorophenol is produced.Brominution. -The action of bromine on p-hydroxy- and dihydroxy-diphenylmethanes forms the subject of several long communicationsby Zincke and his collaborators in continuation of their previousresearches on the bromination of phenols. Only a brief summary ofthese papers can be given Di-p-hydroxydiphenylmethane combines inacetic acid solution with four atoms of bromine, When treated in thecold with bromine, it takes up two additional atoms.The hexabromideis colourless and unchanged by alkalis. If it is heated with brominein a sealed tube, a seventh bromine atom can be introduced, and entersthe methylene group ( I or 11) :Br Br Br H Br()/=\/C*-/-\;OH\=/-I \-/Br Br Br Br Br Br Br Br Br BrI. 11.This substance no longer possesses the properties of a normalbromide, but, according t o Zincke, those of a pseudo-bromide; for itreacts with alcohols, acetone, and aniline, forming compounds whichdissolve in alkalis.The product formed by the action of a smallquantity of methyl alcohol on the heptabromide, or by adding waterEer., 1904, 37, 4010.AnnaZen, 1904, 330, 61 ; 334, 342, 36796 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.to the acetone solution, is hexabromohydroxybenzylidenequinone, andpossesses the following structure :Br Bro/='\ : c H . /-\0 H.\=/ \-/Br Br Br BrIt crystallises in red needles. Its quinonoid character is determinedby the additive compounds which it forms, and which are the same asthose obtained by the direct action of the same reagents on the hepta-bromide.Br BrThese compounds have the general formula,HO/-\.CH./-\OH.\ - / I \-/Br Br OX Br Brin which OX = OH, 0-CH,, 0.C,H5, NH*C,H,. They dissolve in alkaliwithout change, forming colourless solutions.The heptabromide iscompletely reduced to the hexabromide with hydriodic acid. Whenzinc and hydrochloric acid, on the other hand, act on an etherealsolution of the heptabromide, the reduction proceeds slowly, and theproduct contains a substance which gives a violet colour with alkali.The author regards this compound as the quinonoid form of the hexa-bromide.I n a later paper, Zincke and Fries have studied the action of chlorineand bromine on 2 : 3-dihydroxynaphthalene. When excess of chlorineis present, the tetrachlorodiketo-derivative is first formed,H C1,which on reduction yields a dicblorodihydroxynaphthalene. The latter,when acted on by strong nitric acid in the cold, forms a curiouscompound, to which the following formula is provisionally assigned :Bleaching powder converts the tetrachlorodiketone into the corre-sponding hydrindene derivative, which, with alkalis0 RG AN IC CH EM I S‘T 11 1’ - C YC L IC DIVISIONS.97CC1,/’\,/\I II G‘o 7 \/\/CCl.,Tetrachloroketohydrindene.breaks up into phthzllidecarboxylic acid, and on oxidation with nitricacid into phthalonic acid,CO C0,H/\/I t/\\/\1 1 0\/\CO*CO.,H\/\/’CH CO,,H YPlitlislidecarboxylic acid. l’lithaloiiic acid.The action of bromine on 2 : 3-dihydroxynaphthalene gives similarresu1t.s to the above.I n a former paper 1 these authors investigated the action of chlorineand bromine on stilbene. I n a later the :ictioci ofthese rengpts on di-p-acetoxystilbene has been studied. An additivecomponnd is first formed, having the following general formula, inwhich X = C1 or Br, and exists in two isomeric forins, like the stilbenederivative :The less fusible modification, on heating, loses halogen hydricte, and isconverted into di-p-acetoxystilbenemonohalicle, which, with dcoholic:potash, loses a further inolecule of halogen hydride whilst unclwgoingsimul taneons hydrolysis, and yields di-p-hydroxytolune :Dihydroxytolane dissolves in strong sulphuric acid to a red solution,which is probably due to the formation of a quinonoicl compound.When methyl-alcoholic potash acts on either modification of thehalogen additive compound of diacetosystilbene, the same methoxy-derivative is produced :H*/-\*CH--cH*/-\oH.\-/ I \--/O*CH, b*CH,The dibrornide additive compound of di-p-hydroxystilbene, which hasthe properties of a pseudo-bromide, is decomposed by water into stilbene-Annnlen, 1902, 325, 19, 44.Ibid., 1904, 335, 157.VOL. I. 98 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.y uinone, a highly reactive substance which crystallises in bright redneedles :o/=>: \= CH-CH:/-)~. \=The two forms probably correspond to hydro- and isohydro-benzoin,and the same compound is produced when strong sulphuric acid actson the halogen additive compound of diacetoxystilbene with theelimination of acetyl halide.The bromination of phenols has been studied by Hewitt, Kenner,and Silk,l who find that when one molecular proportion of bromineacts on ordinary phenol the character as well as the relativequantities of the products vary with the conditions.Absence ofwater and presence of strong mineral acids favour the formation ofp-bromophenol. If more than one molecular proportion of bromine isadded to phenol dissolved in strong sulpharic and glacial acetic acids,the second molecule of bromine is utilised very slowly, the sulphuricacid hindering substitution in the ortho-position ; but with excess of73 per cent, sulphuric acid the action takes place readily, and 2 : 4-di-bromophenol is obtained.Conclensation.Among the various reagents which have been employed to effectcondensation, perhaps the most interesting, because of the possibleinsight they afford into the synthetical agents used by the livingorganism, are ammonia and the primary and secondary amines(diethylamine and pipericline).A summary of the various condensa-tion products obtained by this means between aldehydes on the onehand and 1 : 3-diketones and similar compounds on the other is givenby Knoevenagel,2 who has himself made a comprehensive study of thisreaction. The range of compounds with which aldehydes condenseincludes suhstilnces having the formula RCH,*NO,, like nitroethane andphenylnitroethsne, and also 2 : 4-dioitrotoluene. Ketones condensewith ethyl cyanoacetate, ethyl acetoacetate, and again ethyl cyanoacetatecondenses with unsaturated ketones, like dibenzylideneacetone, ethylfumarate, and carvone, forming products having the nature of additivecompounds.Products of the condensation of formaldehyde with aromatic com-pounds have been the subject of numerous memoirs and patents.I nthe past year, the following papers, among others, have appeared onthe subject. Condensation products of phenols with formaldehydehave been studied by Simon3 and B ~ e h m . ~ The condeusation iseffected in aqueous solution with or without the addition of acid.Tmns., 1904, 85, 1225.A~m-den, 1903, 329, 30.Ber., 1904, 37, 4461.Ibid., 269ORGANIC CHEMISTRY- CYCLIC DIVISIONS. 99With orcinol, to take one example, methylenebisorcinol is formed,and similar products are obtained with derivatives of phloroglucinol.HO~)OH HOAOH ,/-- CH,---/ 1\/CH3 CH,hlethylenebisorcinol.Rusche and Berkhout,l working along similar lines and in con-tinuation of former researches, have obtained from p-nitrophenol andformaldehyde in presence of dilute sulphuric acid, 5-nitrosaligeninmethylene ether :0The nitrocresols and a-nitro-a-naphthol behave in a.similar manner.Formaldehyde reacts with hydroxyquinol in presence of sulphuricacid, with the formation of hexahydroxydiphenylmet bane,,Betti 3 has obtained from /&naphthol and formaldehyde in presence ofexcess of ammonia a trihydroxynaphthylmethyleneamine having theformula (OH*C,,H,*CH2),N, and Blaise arid Gault have shown thatformaldehyde condenses with 2 molecules of ethyl oxalate in presenceof pyridine, giving a substance of the formulaC0,Et*CO*CH(C0,Et).CH,.CIE(C0,Et)*CO*C02Et,which yields dioxypimelic acid, CO,H*CO*CH,*CH,*CH,.CO.C0,31,on hydrolysis.Other interesting cases of condensation with form-aldehyde are the production of the compounds C5H,N*CH2*CH2*OH andC,H,N*CH( CH,*OH), from a-picoline, which were originally obtainedby Koenigs and Happe,5 and have been more fully examined by Lippand Richard.6Tschitschibabin 7 has shown that similar products are obtained froma- and y-benzylpyridines. Alkylaminobenzaldehydes have been preparedindirectly by the action of formaldehyde on the alkylanilines byUllmann and FreybsCondensation products of beuzilic acid with phenols have been pre-pared by Geipert,g in which the carbinol carbon of the acid attachesCH2CC,H,(OH)312.Annalen, 1904, 330, 82.Liebermann and Lindenbaum, Ber., 1904, 37, 1171.3 Oazzettn, 1904, 34, [i], 212.Bey., 1902, 35, 1343 ; 1903, 36, 2904.7 J.pr. Chem., 1904, [ii], 69, 310.Ibid, 664.4 Compt. rend., 1904, 139, 137.]bid., 1904, 37, 737.8 Ber., 1904, 37, 1207.H 100 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTBY.itself to the para- or ortho-position relatively to the hydroxyl groupof the phenol ; in the one case, parahydroxy-acids are formed (I), andin the other, lactones (11).CH3 CH,/-\OH (C(jH5P- /-\CH,.(C,H,’,T:-\-- / I \-/C0,H CH, co-0I. 11.By the condensation of aldehydes with phenols, Liebermann andlindenbaum,’ Schreier and Wenzel,, and Liebschutz and W e n d haveobtained flixorone derivatives.From among the many other examples of condensation which haveappeared during the current year, the following have been selected.Moureu 4 has continued his investigations on the condensation ofacetylenic esters with alcohol in presence of sodium ethoxicle.Theproduct is a mixture of diacetal and the corresponding alkyloxy-ethylene ester. Thus, ethyl phenylpropiolate and sodium ethoxide giveC,H,* C( O~C,H,),*CH,~CO,-C,H, and C,H,*C( O*C,H,) :CH* CO,*C,H,.By the action of sodium alkyloxides and phenoxides on acetyleneketones, only the unsaturated alkyloxy- or phenyloxy-ethylene ketoneare formed.Piccinini 6 finds that aldehydes condense with ethyl cyanoacetate,in presence of ammonia, and yield secondary amides of the formulaHCH(CN)*CO*NH,, which on boiling with baryta solution are hydro-lysed to substituted malonic esters. I n a later paper, he shows thatcertain aromatic hydroxyaldehydes form 7-substituted dicyanoglut-aconimides by this reaction.Vanillin gives the ammonium salt ofhydroxy-y-methoxyphen yldicyanoglutaconimide,C*CGH,(OH)*O.CHsCN-HC \ C CNO C b\/ NH;OCNSimilar condensation products have been obtained by Issoglio withthe nitrobenzaldehydes.Giffrida and Chimenti have prepared, by condensing pyrotartaricor pyruvic acid with p-aminophenols, imides or diamides of the follow-ing formula :CH3* VH* F0>N*C6H4*OR CH,*yH CO *NH *CGH,*ORCH*CO CH,*CO*NH*C6H,*OR ’Ber., 1904, 37, 1171.l b i d . , 139, 208.Monntsh., 1904, 25, 311.Comnpt. rend., 1904, 138, 206.Atti. R. Accnd. Sci. Torino, 1904, 39, 121,6 Gazzetta, 1904, 34, [ii], 261.3 Ibid., 25, 319.7 Ibid., 39, 140ORGANIC CHEMISTRY-CYCLIC DIVISIONS.101Schoeltz and Huberl have obtained a series of condensation pro-ducts by combining aromatic aldehydes with y-aniincncetophenonein an alcoholic solution containing caustic potash. Renzaldeh ydegives the compound C,H,*CH:N*C,H,* CO-CH: CH*C,H,.Auwers2 has shown that the condensation products of pseudo-phenols and tertiary bases like diniethylaniline, to which be formerlyascribed a different formula, me in reality derivatives of diphenyl-methane. The condensation product of pseudocuiiieiiol tribromide (I)has the following formnla (11) :CH, Br CH3 Br/-\-cH,+/-\N(cH~), . \-/ \-/ OH/-'\CH,Br --+ OH \-/Br CH, Br CH,I. I I.It may be observed that the term pseudophenol has been applied tothose br ominated methyl phenols which contain a mobile bromineatom in the side-chain (in the para-position to the hydroxyl group),and which no longer dissolve in alkalis.In t ram o l e c u I ar Chcc rzge.The clearer views which in recent years have obtained with respectto the phenomenon of dynamic isomerism, wherein the mobility of ahydrogen at,om is usually the determining factor, have had the effectof directing more attention to intramolecular changes of all kinds, andto the special conditions which govern them.A molecular change ofsome interest has been very fully investigated by Willstatter andKahii in the case of the betaines. They find that the quaternarsy deri-vatives of a-, p-, and y-amino-acids of the aliphatic series exhibitcharacteristic differences on heating.The a-betaines are convertedinto esters of tertiary amino-acids, the simplest /I-betaine (propio-betaine) isomerises into the trimethylamine salt of acrylic acid, whereasthe y-betaines, like butyrobetaine, decompose into the lactone andtrimethylamine. The aromatic betaines, on the other hand, all behavein a similar manner. The o-, m-, and p-betaines of amino-acids areconverted on heating into the ester of the dirtlkylamino-acid thus :(/-GO ' IBer., 1904, 37, 390.Bcr., 1904, 37, 401, 1853, 1858.2 Annalen, 1904, 334, 264102 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Another case of molecular change has been observed by Auwers.1I n the course of experiments on the phenol bromides, Auwers foundthat by the action of bases on acetyl compounds of the generalformula C6X,(O*C2H,0)*CH,Br, in addition to the replacement of thehalogen by the basic substituent, the acetyl group frequently detachesitself from the oxygen and passes to the nitrogen atom.Thus, by theaction of aniline on the acetyl derivative of dibromo-o-hydroxy-benzyl bromide in benzene, dibromo-o-hydroxybenzylacetoanilide isformed :Br RrFor this reason, the O-esters of o-aminophenols and o-hydroxy-benzylamines cannot be isolated, since they isomerise a t once into theN-esters :A /\ /\ /\ () iSH2-+l INH*C,H,O ; I/CH2*NH2-Jt \/ /CH2*NH*C2H30.0 a C2H30 OH\/O*C2H,0 OHSimilar observations on the intramolecular conversion of amino-phenylcarbonates have been made by Stieglitz and Upson.2 Some-thiiig in the nature of the reversal of the above phenomenon has beeninvestigated by Chatbaway and L e ~ i s , ~ who have shown that byheating diacylanilides with hydrochloric acid or zinc chloride, o-or p-substituted acylaminoke tones are produced.C6H6*N( CO*R), -+ Re CO*C,H,*NH* C0.R.That is, one acyl group passes from the nitrogen atom to thenucleus.A similar process is described by Eijkmsnn.4 The acylphenols, when heated with zinc chloride, are converted into phenolicketones by the entrance of the acyl group into the nucleus.I n this connection may also be mentioned the interesting intra-molecular changes of dimethyldiacetylpyrone which have been studiedby Collie.5The mechanism of the conversion which was examined by Claisen,Annalen, 1904, 332, 159 ct seq.Arner.Chem. J., 1903, 31, 4 5 8 ; 1904, 32, 13.Tyans., 1904, 85, 386, 589.Chcmisch. WceEbZatl, 1904, [i], 453.Tmns., 1904, 85, 971ORGANIC CHEMISTRY-CYCLIC DIVISIONS. 103whereby the 0-acyl derivative of ethyl acetoacetate changes to a C-acylderivative, y% 7%F:E*O*COCH, -+ 70YH*CO*CH, ’CO,*C,H, CO,*C,HShas been re-examined by Dieckmaiin and Stein,l who pronounce infavour of Claisen’s view that the change is rather inter- than intra-molecular.A d d i t i v e Go mp o u n d s.It has long been known that many unsaturated compounds lose theproperty of uniting with bromine. Nef considers that this additivefunction is determined by the chemical nature of the elements andgroups attached to the doubly-linked carbon atoms.Bauer,3 who hascollected a number of facts relating to this question, confirms Nef’sviews, for he finds that the power of combining with bromine is diminishedwith the increasing number of carboxyl, ester, phenyl groups, orbromine atoms which are attached to the unsaturated carbon atoms.I n certain cases, alkyl groups, when present with the above groups,produce the same effect. Interesting observations of the same naturehave been made by Klages4 on the reduction of substituted styrenes.Sodium and alcohol reduce with clifficulty styrene derivatives, havingthe formulae C,H,*CH:CR, and C,H,.CR:C‘R,, and it is well knownthat unsaturated acids like /3-dimethylacrylic acid, (CH,),C:CH-CO,H,and teraconic acid, (CHJ,C:C( CH,*CO,H)*CO,H, cannot be reduceda t all.Closely related to the above is the behaviour of the bromineadditive compound of unsaturated compounds towards water andalcohol.Hell and Bauer divide the aromatic propylene dibromidesinto three classes, (1) normal bromides, which, like phenylpropyleneand o-auethole derivatives, are unaffected by water or alcohol ; (2) un-stable dibromides, which lose hydrogen bromide and pass into mono-brominated propylene compounds like the bromides of diphenyl-,methylphenyl-, and anisylphenyl-propylene, and (3) moderately stabledibromides, which, like p-anethoTe derivatives, can be isolated and withalcohol exchange one bromine for one alkoxyl group.Many reactions of recent years point to the analogy existing betweenthe additive compounds formed by aldehydes and ketones on the onohand, and by those substances which contain doubly-linked carbon onBcr., 1904, 37, 3393.Ber., 1904, 37, 3317.Ibicl., 1261.Asmalen, 1897, 298, 208.Ibicl., 924, 1721, 2301104 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the other.We refer here more especially to additive compounds withsodium hydrogen sulphite, sulphurous acid, and hydrocyanic acid.Tiemann 1 has collected a number of examples of ‘‘ hydrosulphonicacid” derivatives of this class and a further contribution to thesubject has been recently made by Knoevenagel and his collaborators,who have directed their attention more particularly to ap-unsaturatedketones cmtaining the group CH:CH.CO. Compounds of this classcombine readily with sulphurous acid and sodium hydrogen sulphite,forming hydro-a- or -p-sulphonic acids of the formula-CH,*CH(SO,Hj*CO- or -CH(SO,H)*CH*CO-.The additive compounds of unsatnrated ketones and acids withhydroxylamine have formed the subject of inany former conimunica-tions by Harries and by Posner.A further memoir on the action ofhydroxylamine on unsaturated acid esters is contribu t ecl by Harriesand Haarmann 3 dnring the current year. Ruhemann and Watson 4hare obtained a series of crystalline additive compounds of olefinicketories with aromatic amines. To take one example : benzylidene-acetylacetone and aniline form a compound of the formulaCGH,*CH(NH*C,H,)*CH(CO*CH,),.Posner 5 has also published a further paper on the combination ofmercaptans with unsaturated ketones, which, although too long toabstract, has considerable technical importance.The formation of additive compounds with hydrocyanic acid hasbeen studied by Lapworth and by Knoevenagel wit,h results of con-siderable interest.Lapworth has showns that the presence of small quantities ofbases or potassium cyanide hastens the reaction in virtue of the factthat the basic substances diminish the concentration of the hydrogenions, but increase that of the cyanogen ions.Additive compounds of azo- and diazo-compounds and quinoneswith snlphuric acid have been previously described by Hinsberg,” andby Hantzsch and Glogauer.lo Kohler and Reimer l1 have now shownthat both aliphatic and aromatic aldehydes, a/3-nnsatnrated acids andketones possess the same property.I n a general review of the additive properties of up-unsaturatedketones, including his own observations on the additive compoundswhich they form with hydroxylamine, referred to above, Harries 12shows that Thiele’s theory of partial valencies cannot be entirelyBer., 1898, 31, 3297.Jbbicl., 252.Trans., 1904, 85, 1170. Ber., 1904, 37, 502.Ibid., 1904, 37, 4038.ti Proc., 1904, 20, 54, 245 ; Trmns., 1904, 85, 1206, 1214.7 Ber., 1904, 37, 4065.9 Ber., 1894, 27, 326.(1 -4mer. Chevz. J., 1904, 31, 163.Tyaias., 1903, 83, 997.lo Ibid., 1897, 30, 2548.l‘’ Annalen, 1904, 330, 185ORGANIC CHEMISTRY-CI’CLlC DIVISIONS. 105reconciled with the known facts. Thiele’s theory, it may be stated, isintended to account for the phenomenon so frequently observed duringthe reduction or bromination of a “conjugated system” (or group contain-ing two adjoining pairs of double bonds, u = b - c = d ) that the two endatoms only of the chain are capable of entering into union.Thielesupposes that each of the two pairs of atoms is provided with a partialvnlency in virtue of which the addition is first effected. Moreover,t.he partial valencies of two adjoining atoms can unite or become‘( conjugated,” leaving thus only the two end atoms free t o combine.When this occurs, the bonds between the middle atoms are transposedinto an ordinary double bond. The stages in the process may berepresented ns follows :Now Harries finds, contrary to the above view, that unsaturatedketoxiines and aldoximes can be reduced to unsaturated amines andthat acrolein derivatives can also be converted by the aluminiummercury couple into monohydric alcohols.Similar views have beenexpressed by Kohler,l who points out that, provided the addendaare alike, Thiele’s view may hold, but it is otherwise if they aredifferent>. Erlenmeyer, jun.,2 also finds that when cinnamoylformicacid, C,H,*CH:CH.CO*CO,H, and similar compounds undergo re-duction, it is always the ketone group which is attacked, with theformation of py-unsaturated hydroxy-acids.I n all these cases, it will be seen, the adjacent and not the end atomsbecome saturated.U n s at ur u t e d 239 ds. oca r b o n s.Few discoveries of recent years have attracted more attention thanthatof the remarkable series of unsaturated hydrocarbons which Gomberghas isolated by the action of metals (zinc, silver, or mercury) ont riphenylchloromet hane and analogous compounds.The interestdepends, not only on the isolation of hitherto unknown univalenthydrocarbon groups in which carbon is tervalent, but on the curiousproperties of the new compounds, Various attempts which have beenmade * to bring triphenylmethyl into line with recognised structuralformulze have failed to carry conviction to the discoverer of this com-pound. I n the free state, triphenylmethyl is bimolecular yet distinctfrom hexaphenylethane, into which, however, it readily polymerisesAmer. Cheijz. J., 1904, 31, 243.Ibid., 1900, 33, 3150 ; Amer.Chem. J., 1901, 25, 317 ; Bcr., 1901, 34, 2726 ;Heiiitschel, Ber., 1903, 36, 320, 579 ; Tscliitschibabit~, i b i t l . , 1904, 37, 4709.a Ber., 1904, 37, 1318,1902, 35, 2397 ; 1903, 36, 376, 3928 ; 1904, 37, 1626106 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.with various catalysts, notably hydrochloric acid. It is unsaturated,combining directly and very readily with oxygen to form a peroxideand with the halogens to form triphenylmethyl halides. It combines,moreover, with ethers and esters, although in these cases it still retainsits unsaturated character. Since triphenylmethyl, triphenylmethylchloride, its double salts with stannic chloride, and the carbinol all dis-sociate and conduct in liquid sulphur dioxide,l it follows that triphenyl-methyl possesses the basic properties of a univalent metal, and this viewis supported by the fact that the halide compounds form perbromidesand periodides.Triphenylmethyl is a colourless, crystalline solid, but in organicsolvents it yields a yellow solution.This change in colour is attributedby Gomberg to the formation of the coloured ion (C,H,),C. The yellowsolution of the triphenylhalogenmethane is accounted for in the sameway by dissociation into the halogen ion and triphenylmethyl ion fromwhich Gomberg deduces the Rosenstiehl formula for pararosanilinechloride, (NH,*CGH,),C*C1, wherein the colour ion is the basic complexCompounds similar in character to triphenylmethyl have been pro-duced by the action of metals on other triarylchloromethanes.Theditolylphenyl, tritolyl, trinitrotriphenyl, &c., compounds give colouredsolutions (the first two being orange and the third greenish-blue)which, on warming, assume a violet, and finally a magenta colour.On cooling, the colour changes occur in the reverse order.Another unsaturated compound of somewhat remarkable characteris that obtained by Thiele 2 in the course of an investigation which hadfor its object the preparation of the compound CH2:CGH4:CH2. Al-though the desired result was not attained, the tetraphenyl derivative,(C,H5)2C:C6H,:C(CGH5)2, of this hydrocarbon was prepared. Tetra-phenyl-p-xylylene is obtained by boiling the bromide, C,H,[CBr(C,H,),],,with benzene and molecular silver. The new substance crystallisesin orange-red needles and the solutions possess a yellow or orangefluorescence.( H2* 'GH4 )3"Ilycl7~ocyczic Compourzds.I n view of the close relation which subsists between hydroaromaticcompounds and many natural products such as are described in asucceeding section (p.1 IS), the preparation and properties of this groupof compounds possess a special interest and importance.The very large number of synthetical methods which have beenannounced from time to time do not appear to have exhausted thisfield of research, and many new reactions have been recently described.Walden, Bm., 1902, 35, 2018. Ibid., 1904, 37, 1463ORGANIC CHEMISTRP-CYCT,IC DIVISIONS. 107Sabatier and Senderens' method for preparing hydrocyclic alcohols andamines has already been referred to (13.93).and Perkia and Thorpe 2 have shown thatring formation occurs when certain dibasic acids are heated alone orwith acetic anhydride. To take one example, the important substance8-ketohexnhydrobenzoic acid (p. 11 '7) is obtained from pentane-ayc-tri-carboxylic acid by heating with acetic anhydride :Lapworth and ChapmanGarner,3 some time ago, prepared A2-ketocyclohexene derivatives bycondensing benzoin and benxylideneacetone. The reaction has beenextenclecl ancl a variety of hyclrocyclic compounds prepared. The com-pound obtained from benzoin and beiizvlicleneacetoi?e is 3 : 4 : 5-tri-phei~~l-4-hyilro2iy-A~-ketoc,~cZohexene :A similar condensation product, triphenylcyclohexenone, has beendescribed by W i e l a ~ ~ d , ~ who obtained it from dibenzyl ketone andcinnamaldehyde in presence of diethylamine, and another ketone,diphenylacetone, has been converted by Vorliinder and von Liebig intodiphen ylcy clopentane.Another synthesis of a hydroaromatic compound is described byvon Pechmann and Sedgwick.6 Acetonedicarboxylic acid (I) condenseswith ethyl p-iodopropionate ancl forms a derivative (11) which breaksup with boiling hydrochloric acid into acetoiiedipropionic acid(111) :1 Y73ct?LS., 1900, 77, 464.Auer. Cke,ti.J., 1904, 31, 143.I b i d . , 1133.Ibid., 1904, 85, 138, 416.Bcr., 1904, 37, 1142.lbirl., 3816108 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRYOn heating the acid to the melting point, water is removed, anddihydroresorcyl- or diketohexamet hylene-propionic acid is produced :CH2-CO CH2-COI CH,*CH,*CH,*CO,H -~ QH, CH*CH,*CH,*CO,H.CH2 OHCH2-COBuchner and BrarenI II II1CH,-CO Ihave shown that i t is possible to prepare aderivative of cycloheptene by the action of ethyl diazoacetate on benz-ene.The experiments OE Buchner and Scheda,2 undertaken with theview of obtaining an eight-membered carbon ring from ethyl A'-cyclo-heptenecarboxylate, gave in the first place an oily ester containing abridged ring of S atoms./*-0-j-C02* C,H5 + N,:CH*CO,*C,H, = \.-.-. ICO,*C,H, /-'-]>-c02.c2H5.Hydrolysis produced a mixture of oily products consisting of un-saturated compounds, from which, after oxidation with permanganate,two isomeric, crystalline acids of the formula C,H,,(CO,H), wereisolated, the nature of which has not yet been ascertained.Demjanoff , 3 who succeeded in converting a tetramethyleneamino-compound (I) into a cycEopentene derivative by meacs of nitrous acid,has now produced a seven-membered ring from a six-membered ringcompound (11) in the same way :\.-+.N2 +CH, CHz7H2* ?H*CH,*NH, CH,/- -\CH~CH,*NH,.CH,* CH, \--/CH, CHzI. 11.On treating the hydrochloride of the amine with silver nitrite, suberylalcohol is formed.Rabe and Weilinger 4 describe an interesting synthesis of bridgedrings from ethyl dihydrocarvonylacetoncetate (I). They find that byintramolecular aldol condensation and the simultaneous removal ofcarbethoxyl, a dicyclic, ketonic alcohol is produced :C,H5*C0,*yH-F)H-QH2 vH2-yH-QH2YO YH*CH, FH*C<:E: 70CH, CO- CH, CH,-C(0Hj-CH,I. 11.YH-CH, FH*C<:2.Ber., 1900, 33, 3453 ; 1901, 34, 952.J.Russ. 1 hys. C'hem. Soc., 1904, 36, 166.Ibid., 1904, 37, 931.Ber., 1904, 37, 3816ORGANIC CHEMISTRY-CYCLIC DIVISIONS. 109The latter has been reduced to the corresponding saturated dicyclichydrocarbon. Other dicyclic comporinds have been prepared by asimilar method from methylcycZohexanoae.1Not less important than the synthesis of hydroaromatic compoundsis the knowledge of effective means of transforming them into corre-lated compounds of the aromatic series.Von Baeyer and others have accomplished it by exhaustive bromin-ation and subsequent reduction of the bromine derivatives, andMarkownikoff employs bromine and aluminium bromide wherebyaromatic bmmine compounds are obtained. Knoevenagel has usedbromine alone, and Wallach nitric acid for the same purpose. Inter-esting results in this connection have been obtained by Crossley 2 andhis collaborators, I n a recent paper,3 Crossley has shown that bromineacts on 3 : 5-dichloro-1 : l-dimethyl-A2 ‘‘-dihydrobenzene ; among otherproducts, 3 : 5-dichloro-o-xylene is formed :A curious feature of this reaction is the wandering of a methylgroup to an adjoining carbon atom such as von Baeyer and Villigerhave previously observed in the case of euterpene and isogeraniolene.Heterocyclic Compounds.-Two interesting syntheses of pyridine com-pounds are recorded during the year, one of chloropyridine fromchlorocoumalinic acid, by von Pechmann and Mills,5 and the other of2 : 4 : 6-trioxypyridine from ethyl a-cyano-P-iminoglutarate, by Baron,Remfry, and Thixpe.GThe action of hydrogen peroxide on piperidine was examined byWolffenstein some years ago, and he supposed a t the time that theproduct was 6-aminovaleraldehyde. Seeing that the same reagentproduced oxyammonium compounds from N-alkylpiperidines as well asfrom secondary aliphatic amines, the original view as to the nature ofthe oxidation product of piperidine seemed doubtful.Haase andWolffenstein now bring conclusive evidence to show that the com-pound is, in reality, a piperidinium oxide or oxime, and is representedbv formula I or I1 :H*N:OH~c/)CH,H,c{,cH,.N*OHI.11.1 Ber., 1904, 37, 1671.3 Ibid., 1904, 85, 264.5 Ibid., 1904, 37, 3829.7 Ber., 1904, 37, 3228.Trans., 1902, 81, 831, 15-83 ; 1903, 83, 116, 495.Trans., 1904, 85, 1726.* Ber., 1898, 31, 2067; 1899, 32, 2432110 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Koenigs has obtained a derivative of quinuclidine (I), which heregards as the possible nucleus of the ‘‘ second half ” of the moleculeof the cinchona alkaloids :CH CH CH*CH,*CH,*OHI. 11. 111.The preparation of P-ethylqriinuclidine (11) is eff ec tecl by condensingy-inethyl-P-ethylpyridine with formaldehyde to y-methylol-methy1-P-ethylpyridine, which is then reduced with sodium and alcohol tomethylolhexahydro-P-collidine (111). If the latter is boiled withbydriodic acid and phosphorus, iodine replaces hydroxyl. When theiodine derivative is set free by the cautious addition of caustic sodaand taken up with ether, the hydriodide of P-ethylquinuclidine slowlyseparates from the ethereal solution.Skraup’s quinoline synthesis has undergone seveid changes sincethe original method was published.The glycerol has been replaced inturn by glycol and by acetaldehyde and the oxidising agent omittecl.The latest modification is the use of amino-compounds with glyceroland arsenic acid proposed by Kniippel.3 The application of the corn-bined new and old method is the subject of a paper by Bartow andM~Collum,~ and the effect of adding metallic salts and of replacingnitrobenzene by cerium oxide is d e w ibed by lSlargosahes,5 but withoutvery definite results.Both pyridine and quinoline, as Oddo and F.L. Sachs? have found,form additive compounds with organomngnesium halides.It has already been pointed out that Koenigs discovered the propertywhich a- and y-alkyl-pyridines and -quinolines possess of condensingwith formaldehyde. This important reaction has been applied to thepreparation of acid derivatives and homologues of quinoline by Koenigsand Menge1,s who have examined the condensation of ay-dimethyl-quinoline with 1 molecule of formaldehyde. The product is a-ethanol-lepidine (I), which gives lepidine-a-carboxylic acid on oxidation, andfrom it lepidine can be obtained by heating :1 Ber., 1904, 37, 3244.2 A review of the present position of the chemistry of the alkaloids is containedin a pamphlet by Julius Schmidt, entitled “Die Rlkaloidchemie in den Jalireii1900-1904” (F.Enke, Stuttgart).3 Ber., 1896, 29, 1704.5 J . pr. Chem., 1904, [ii], 70, 129.J. Amer. C?benz. Soc., 1904, 26, 700.Atti R. Accad. Lincei, 1904, 13, [ii], 100.Ber., 1904, 37, 3088. * lbid., 1322ORGANIC CHEMISTRY -CYCLE DIVISIONS. 111I I ICH2*CH2*OH. \/\/NI.As ay-dimethylquinoline by direct oxidation gives lepidine-y-carb-oxylic acid, the present method offers a simple means of controllingthe course of oxidation. By the introduction of a methylol group intoquinaldine and lepidine, they may in a similar way be converted intoquinaldinic and cinchoninic acid, an operation which is difficult toeffect by any direct method of oxidation.Quinoyl-y-acrylic acid andits reduction product, the y-propionic acid, have also been obtained bycondensing lepidine with chloral and boiling the chloral-lepidine withcaustic potash :Y C,H,,N[CH2*CH(OH)*CC13] -+ C,H,N(CH:dH*CO,H) --+C,H~N(CH,~H,W,H).I n the pyrrole and pyrazole group, the synthetical reactions effectedby condensation, although numerous enough, offer vesy little that isintrinsically digerent from those which have been previously studied byKnorr and others, The reactions consist for the most part in theaction of hydrazine and its derivatives on various ketones and ketonicesters. A special interest, however, attaches to a-pyrrolidinecarboxylicacid (I), the presence of which, together with its hydroxy-derivative,has been detected by E.Fischer and others in the products of thehydrolytic decomposition of various proteicl substances. It hasbeen synthesised by Willstiitterl by the action of amiuonia on as-di-bromovaleric acid. Fischer and Suzuki have now prepared in the sameway from as-dibromovalerylalanine (from the acid chloride and alanine)and ammonia the corresponding pyrrolidine derivative (11). For thefirst compound Fischer proposes the name “proline” and for thesecond ‘‘ prolylalaiiine ” :CH,*CH,*CH,*CH*CO,H CH,*CH,*CH,*CH*CO*NH.CH(CH,).CO~H\ / \ /\NH/11.Other proline derivatives have been obtained by Fischer and Abder-halden,3 using similar methods.A number of new aminopyrazoles have been prepared by Knorr\NH/I.Proline. Prolylalanine.Be?.., 1900, 33, 1160.Ibid., 3071.Bid., 3520.Ibid., 1904, 37, 2842112 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.from the corresponding acids, and Michaelis has obtained a series of" thiopyrines " or thiopyrazoles. Michaelis' method is to add to an alkalihydrosulphide, into which carbon disulphide vapour has been passed? anaqueous or alcoholic solution of the methyl chloride or iodide ofphenylmethylcliloropyrazole, or an analogous compound, or to act onantipyrine hydrochloride or similar compound with sodium thiosulphate.Thiopyrine is represented by the following formula :[ts physiological action resembles that of antipyrine.has the following structure :The parent sribstance of the thiopyrines has also been obtained andN*C,H, N* C,j K,Nn/),C*SH , 01' d \ C S .C H3.C--- C H UFI,.C'i'CE€,An interesting synthesis of pipermine derivatives by the polpmerisa-tion of chloroethylamine and similar compounds is described by Knorr,2who finds that chloroethyldimethylamine (I), either free or in aqueoussolution, polymerises to dimethylpiperazine hydrochIoride (11) :I.I I.The latter decomposes with alkalis into tetraniethylethylene-diamine (HI), ethanoldiinethylamiiie (IV), and acetylene :111. IV.The Teypenne and Carnplzor Group.The most important synthesis of recent years is that of r-camphoricacid by K ~ r n p p a , ~ which, although strictly belonging t o the latterpart of 1903, is shortly reproduced for reference. Ethyl diketoapo-Annalen, 1904, 331, 197 ; Ber., 1904, 37, 2774.Bey., 1904, 37, 3507.Ibid., 1903, 36, 4332ORGANIC CHEMISTRY-CYCLIC DIVISIONS. 113camphorate, which is the starting point, was prepared by Komppa bycondensing ethyl oxalate mith ethyl &3-dimethylglutarate :CO,R HCH*CO,R CO*CH*CO,RI + >C(CH,), = I >C(CH,), + 2R*OH.A methyl group was then introduced by the action of sodium andmethyl iodide. This was reduced to the dihydroxy-acid (I), thenboiled with hydriodic acid and red phosphorus, and converted into theunsaturated acid ([I). The latter combines with hydrobromic acid andforms a bromo-acid (111), and is then reduced mith zinc dust andacetic acid to r-camphoric acid (IV), which is identical with the productCO,R HCH*CO,R CO*CH*CO,Robtained from camphor by oxidation and subsequent racemisation :HO* CH- CH* CO,H C H I C-CO,H CH*CH*CO,HHO* CH*C((Y,H,)*CO,H CH,* C(CH,)*CO, H(I) Diliydroxycamphoric acid.I >WH,), or II >C(CH,),CH*C(CH,)-C02HI >C(CH&(11) Dehydrocamphoric acid.CHRr*CH-CO,H CH,*CH*CO,HCH,-C( CH,) *@O,H CH,*C( CH3)*C0,H(IV) r-Camphoric acid.I >C(CH,), I >C(CH3)2(111) B-Bromocamphoric acid.Camphoric acid may be converted into homocamphoric acid2 byreduction of the anhydride (V) to campholide (TI), which yieldscyanocamphoric acid (VI I) with potassium cyanide, and, finally, homo-camphoric acid on hydrolysis (VIII) :co CH, ,CH,*CNC,H1/>O -+ CsHl,(>U -+ C,H,,/ -+430 \C02HTI.VII.\covV1II.When the barium salt of homocamphoric acid is distilled, it breaksup into camphor and barium carbonate :I n this way, the complete synthesis of camphor has been effected.Although Komppa's synthesis has solved the camphor problemas far as its structure is concerned, there remains a large andproductive field of research connected with the chemistry of thesesubstances, which is still being carefully cultivated,Ber., 1901, 34, 2472.Haller, Compt. rend., 1896, 122, 446.VOL. I. 114 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The synthesis of what may be termed the fragments of the camphormolecule has formed the subject of several previous communicationsby W. H. Perkin, jun. During the present year, the same chemist hassucceeded in obtaining synthetically i-a-campholactone, i-a-campho-lytic acid, and P-csmpholytic acid (isolauronolic acid).l The steps inthe process may be briefly described as follows : ethyl cyanoacetahecondenses with ethyl bromoisobutyrate,C0,Et *yH*CNCO,Et *CMe,CO,Et*CHNa*CN + C0,Et*CMe2Rr = + NsBr.The sodium compound of this ester reacts with etbyl /I-iodo-propionate and gives ethyl cyanodirnethylbutanetricarboxylate :C0,IWhen the latter is boiled with hydrochloric acid, it is hydrolgseiand carbon dioxide removed a t the same time.The product is a-di-methylbutane-a@-tricarboxylic acid. If the dry sodium salt of theacid is heated with acetic anhydride a t 140", a further molecule ofcarbon dioxide is evolved and inner condensation occurs :y-Keto-/3B-dirnethylpentanie thylene-a-carb-oxylic acid.Methyl and hydroxyl groups are then introduced into the ketonegroup of the ester by Grignnrd's method,CH,-CO CH,*CMe(OMeI)I I I I CMe, -+ I ?Me,CH2:bH*C02Et CH,* CH*CO,H CH,* CH--COTbe last product is i-a-campholactone, If the lactone is heatedwith hydrobromic acid, it is transformed into y-bromotrimethyl-pentamethylenecarboxylic acid, which with sodium carbonate givesi-a-campholytic acid :CH,-CMe-0 CH;CMeRr CHICMeI I II I+ I CMe, 1 y e 2 1 -+ I y e 2CH,*CH-CO CH,* CH- CO,H CH,*CH*CO,HWhen digested with dilute sulphuric acid, the a-compound is convertedThe acid was identified byTrans., 1904, 85, 128.into P-campholytic or isolauronolic acidORGAKIC! CHEMISTRY-CYCLIC DIVISlONS.115mixing i t with the acid from camphoric acid, which did not affect themelting point (132"), and by oxidisiag it to isolauronic acid :CH=CMe CH,*CMe,CH,~H*CO,Ha-Campholytic acid.8- or iso-Lauronolic acid.Several important contributions to the chemistry of halogen andacyl derivatives of camphor and camphorcarboxylic acid have beenmade by Briih1.l It is impossible within the limits of this report togive more than a very incomplete rtisum,G of his numerous researches.By brominating and iodating hydroxymethylenecamphor underdifferent conditions, the following halogen derivatives have beenobhined (X = Br or I ) :Sodium camphor can be used for the preparation of benzoyl- orformyl-camphor as well as for the alkyl derivatives, in all of which thegroup attaches itself to the methylene carbon. Bruhl finds, on theother hand, that alkyl acetates, acetic anhydride, or acetyl chlorideyield mainly 0-acetyl compounds (I) together with borneolacetate (11) :The preparation of '' aoetylcamphor " is best effected by mazns ofthe magnesium and zinc compounds of bromo- and iodo-camphor byacting on the products with acyl halides and esters.The opticalproperties of these acylcamphors indicate their derivation from thehydroxymethylene type :C:CR*OH .4<boThe action of alkyl and acyl chloride and esters, in presence ofmetals, on camphorcarboxylic acid and its halogen derivatives is thesubject of another memoir, If an alkyl halide is added to the sodiumqompound of ethyl camphorcarboxylate in a non-dissociating medium,like benzene, ligroin, or ether, no action occurs; but alkyl derivativesare obtained if the solvent is methyl or ethyl alcohol.The compoundsthus produced have the ketonic form,CR'* CO,RC,Hl*<~OBer., 1904, 37, 746, 761, 2156, 2163, 2118, 2512, 3943.1 116 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Acyl halides, on the other hand, react readily in a non-dissociatingas well as in dissociating solvents, and give only enolic compounds :Jn order to follow the course of these changes, spectrochemicalmethods (molecular refraction or dispersion) have been adopted.Eriihl finds that the production of tho sodium compound of the esterin different alcoholic solvents is accompanied by enolisation, and theirgreater or less reactivity depends on the degree of polymerisation ordissociation.I n benzene, for example, the sodium compound has3-4 times its normal molecular weight, whereas in alcohol it ismonomolecular and dissociated. Thus, the alkyl halides seem in-capable of reacting with the polymeric form.Synthesis of Natuq*aZ Products.The study of structure with its natural corollary, synthesis, formsso large a part of nearly all organic research and presents so muchnecessary elaboration in matters of detail, that to attempt to conveyan idea of the nature and extent of the current problems in a briefreport on the aromatic group is to court certain failure. I propose,therefore, to consider in the present section only such syntheticalibroblems as have received their final solution.When Komppa’s synthesis of camphoric acid, and consequently ofcamphor (p.113), had added the last link to that long chain of evidence:LS to their structure which had been slowly forged by a multitude ofrkilful workers during years of unremitting study, one chapter insynthetical chemistry was closed. B u t there remained in the terpeneseries a long list of allied compounds derived from vegetable sourceswhich as yet included no single member produced by artificial means.The synthesis of terpin hydrate, terpineol, and dipentene by W. H.Perkin, jun.,l may be counted among the brilliant achievements ofthe year in this field of synthetical chemistry. Both dipentene andterpineol are found in varying quantities in many essential oils.Terpin hydrate, though not strictly rz natural product, is closely alliedto the other two.Tilden described a convenient method for obtainingterpin hydrate from turpentine 21s long ago as 1878, and in thefollowing year first prepared terpineol from it. The structuralrelationship of the three compounds has been established by the jointlabours of Wallach, Tiemann, and von Baeyer.The following are the accepted forniulz of these three coinpouuds :Y?%?is., 1904, 85, 654ORGANIC CHEMISTRY-CYCLIC DIVISIONS. 117p 3 QH3 p 3 3i2 C C W )H,c!,)cH,YHC(0WYH/\H2C/’bHYHC W )/\CCH, CH,/\CH3 CH3 CH3 CHI,Dipentene. Terpineol. Tcrpin.Perkin’s synthesis is effected in the following manner. The startingpoint is 8-ketohexahydrobenzoic acid, already referred to (p. 107) :I t s ester reacts readily with magnesium methyl iodide, and theproduct on hydrolysis yields 6-hydroxyhexahydro y-toluic acid,which had already been obtained by Stephan and Heller by theoxidation of As : 9-menthenol.This hydroxy-acid dissolves readily infuming hydrobromic acid, and the solution soon deposits crystals ofBbromohexahydro-ptoluic acid, from which, on treatment with weakalkalis or pyridine, A3-tetrahydro-p-toluic acid is obtained :The acid, when converted into the ester and acted on with magnesiummethyl iodide, gives terpineol. The latter is transformed, on the onehand, into dipentene by the action of potassium hydrogen sulphate, and,on the other, into terpin hydrate by shaking with dilute sulphuric acidMany of the natural yellow dyes have been recognised as belongingto the group of flavone or flsvonol derivatives.The flavone (I) andflavonol (11) complexes have the following structure, from which thecolouring matters are derived by replacing one or more hydrogen atomsby hydroxyl groups in the numbered rings, and they consequentlypossess phenolic properties :0 0118 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The unravelling of the constitution of these substances is due toSt. von Kostanecki and his collaborators, and to A. G. Perkin, Herzig,Goldschmidt, and others. I n 1898, von Kostanecki succeeded insynthesising the first of the hydroxyflavone dyes, and he has sinceprepared a large number of similar substances, including the naturalproducts chs*ysin (1 : 3 dihydroxyflavone), froin poplar buds ; apigenin(1 : 3 : 4 -trihydr.oxyflavone), from parsley ; and luteolin (1 : 2 : 3’ : 4’-tetrahydroxyflavone), from weld and dyers’ broom.After severalunsuccessful trials, the same chemist has at length devised a methodfor obtaining some of the natural as well as several new flavonolderivatives.This method may be illustrated in the case of fisetin (3 : 3’ : 4-tri-hydroxyflavonol), which is the yellow dye of young fustic and yellowcedar.l The first; step is the preparation of o-hydroxychalkone. Thisis effected by condensing resacetophenone ethyl ether with methyl-vanillin by means of caustic soda :2-Hydroxy-3 : 4-diniethoxy-4-ethoxychalkone.On boiling with dilute sulphuric acid, the latter (111) is converted into3’ : 4’-dimethoxy-3-ethoxyflavonone (IV).OH0coIV.The flavonone derivative is successively treated with amyl nitriteand hydrochloric acid, which yields an isonitroso-compound ; withacetic acid containing 10 per cent.of sulphuric acid, which convertsthe isonitroso-compound into the corresponding tlavonol, and finallywith hydriodic acid, which eliminates the alkyl groups and givesfiset,in :Ber,, 1904, 37, 784ORGANIC CHEMISTRY-CYCLIC DIVISIONS. 1190000 OH.’ c0E’isetin.Quercetin,l from quercitron bark, catechu, sumach, &c., k$mpferol,2from blue larkspur, and galangin,3 from galanga root, have beensynthesised by processes which are merely variations of the above.New methods of synthesis of luteolin4 and chrysin5 have also beendevised by von Kosfanecki.To the steadily growing list of synthesised alkaloids which nowincludes piperine, coniine, atropine, atropamine, belladonine, r-cocaine,tropacocaine, and hyoscyamine, with which the names of Ladenburgand Willsttitter are chiefly associated, must be added the principalalkaloid of tobacco, namely, nicotine.The merit of this new achievement belongs to Picteh m d Rotschy.6The steps in the discovery are briefly as follows : Pictet and Crepihxobtained N-P-pyridylpyrroles (I) by the distillation of P-aminopyridinemucate, which isomerises to ap-pyridylpyrrole (11) when its vnpour ispassed through a red-hot tube. By the action of methyl iodide on thepotassium salt of the latter, u/3-pyridyl-N-methylpyrrolemet hiodjde(111) is formed.This substance is identical with the methiodide ofnicotyrine, obtained by the graduated oxidation of nicotine :Ber., 1904, 37, 1402.Ibid., 2803.5 Bid., 3167.7 Ibid., 1895, 28, 1904.Bid., 2096.Ibid., 2625.Ibid., 1225120 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.I.As nicotine contains 4which may be regarded aswas to reduce nicotyrine.11. 111.atoms of hydrogen more than nicotyrine,its first oxidation product, the next problemThis cannot be effected directly; but bythe action of iodine and caustic soda on nicotyrine from naturalnicotine a crystalline iodine substitution product is obtained (IV)which can be reduced with zinc and hydrochloric acid to dihydro-nicotyrine (V).l The last two hydrogen atoms can be introduced bythe reduction of the perbromide of dihydronicotyrine :,/\ f p - $ ? " 2 $?H2*YH21 1.c CH, /)*CH CH,." ' d C H ,/'\ RH-F I 1-C CH '' '$:CH,TI.I v. v.The new base (VI) appeared to be identical with inactive nicotine.The final problem was how to isolate the artificially-prepared nicotyr-ine from its methiodide. After several unsuccessful trials it waseventually accomplished by distilling it with lime a t as low a tem-perature as possible. Fifty per cent. of the theoretical yield wasthereby obtained. Inactive nicotine was prepared from the product inthe manner described above, and then resolved into its activecomponents by crysta'lising the tartrate. A comparison of d- andZ-nicotines obtained in this wag with natural Z-nicotine is given in thefollowing table.The slight differences in rotation are ascribed by theauthors to the hygroscopic character of the bases :Natural Z-nicotine ... ... ... ... . , . ... 246*1-246.2/730'5 1.0180 1 *0097 - 166.39''Z-Nicotine from the inactive base. 246 -246.51734'5 1.0177 1.0092 - 160'93&Nicotine , , >, 245'5-246'5/729 1.0171 1.0094 +163*17The difference in physiological action of the two active nicotinesappears at first sight very remarkable, although if we consider theactive character of the materials which so lstrgely compose the animaltissues and secretions, it is scarcely surprising that optical isomerideashould produce a different effect; for is not the selective fermenta-tion of yeast and other low organisms a manifestation of thesame thing? Experiments on guinea-pip and rabbits show thatB.p. D 10"/4". D 20"/4". [Ber,, 1898, 31, 2018ORGANIC CHEM1STRI’-CYCT.IC DIVISIONS. 121the I-base is twice as toxic as the d-base. Injection of the I-base intoa guinea-pig produces violent pains and cramp in the extremities ; theinjection of the d-base is painless. Similar differences have beenobserved in rabbits.Adrenaline, the active principle of the suprarenal glands, has beenthe subject of several memoirs which have appeared during the pastyear, and although the complete synthesis of this important substanceis not yet afccit accompli, it may be said to have reached its final stage.The structure and properties of adrenaline have been determined bythe combined labours of Pauly,’ Jowett,2 and Bert~and,~ resulting intwo formulx?, the first of which is preferred by Jowett and the secondby Pauly:HOHO/-\.CH(UH)~CH,~NH~CH,I. \-/HOThe work of Friedmann * seems to confirm the first formula; for hehas obtained, by oxidising the optically active tribenzenesulphonederivative of adrenaline, an optically inactive product which is notdistinguishable from the tribenzenesulpbone derivative of the ketone,H OHO/-\-CO-CH,-NH*CH,.\-/This ketone has been obtained by Stolz by the action of methyl-amine upon chloroacetylcatechol, and has been shown by Hans Meyerto possess qualitatively the physiological properties of adrenaline inincreasing the blood pressure, whilst still more active products wereobtained on reduction.Dakin7 has also obtained a number of basesof the typeHOHO<I)*UO* CH2*NHR,several of which are physiologically active. He has also, by reduc-tion of the methylamine base, succeeded in preparing a substancepossessing the f u l l physiological activity of adrenaline, although itsidentity with the natural product is doubtful.Ber., 1903, 36, 2944 ; 1904, 37, 379.Beitr. chenz. Physiol. Path., 1904, 6, 92.Centralbl. Physiol., 1904, 18, 501.Tmns., 1904, 85, 192.3 Ann. Inst. Pasteur, 18, 672.6 Ber., 1904, 37, 4149.7 Private Communication122 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Another interesting synthesis of a product of the animal organismis that of indole-acetic acid by E1linger.l ' The compound is formed bythe putrefactive fermentation of tryptophan.Its synthesis is effectedby Fischer's method from the phenylhydrazone of the half aldehydeof ethyl succinate :VH2*CH*C10,R $*CH,*CO,R= NH, + CH/CH YH ti 4\kHC,H,*WArtiJcial Dyestuf8.Since the introduction of Fischer and Nietzki's quinonoid formulainto the structure of the triphenylmethane and other dyestuffs, a newstimulus has been given to the study of the constitution of these sub-stances. Among the many investigations which have been pursuedduring the current year, not the least interesting is that which has ledto the discovery by Willstiitter, afayer, and Pfannenotiel of what havebeen sometimes regarded as the parent substances of many dyes,namely, iminoquinone (I) and cli-iminoquinone (11), or the qninone-imines.!?/\I I\/&HI.M/\I I .'\/AHIT.The method first used was to reduce the well-known qninonedichloro-di-imines with hydrochloric acid in ethereal solution :I n a later paper, this process is modified, and the mono- as well asthe di-imino-compounds were obtained by oxidising paminophenol andp-phenylenediamine by shaking the ethereal solution with dry pre-cipitated silver oxide and anhydrous sodium sulphate.Both compoundsare, strange to say, colourless, but become rapidly discoloured in theair and decompose in aqueous solution. The monoimine explodesBe?.., 1904, 37, 1801. ]bid., 1494, 4605ORGANIC CHEMISTRY-CYCLIC DIVISIONS. 123spontaneonsly in the free state, and is more soluble than the di-iininein ether, It also decomposes in alcohol, has a faint odour of quinone,and colours the skin brown.It forms salts with acids, and with phenoland alkali gives a deep blue solution of indophenol; with dimethylaniline and acid, one of phenol-blue. The di-imine does not explodespontaneously like the monimine when heated to the temperature ofboiling water, but only by dropping in strong hydrochloric or sulphuricacid. It is a weak base, which forms salts with acids, which are readilydecomposed by ammonia. With aromatic amines and phenols, thedi-imino-salts produce a t once deeply coloured solutions of indamineand indophenol. A passing reference may be made to WillstPtter’slatest announcement to the effect that catechol can be oxidised withspecially prepared silver oxide in dry ethereal solution to o-benzoquinone,a substance which has so far eluded every attempt to isolate it.l Itcrystallises in brilliant light red, four- and eight-sided plates, whichmelt with decomposition at 60-70°, and exhibits a close resemblanceto P-naphthaquinone in being odourless and non-volatile.The qidnonoid formula of the triphenylinethane colours representsthe colour salts as salts of quinoneimines, but with one possible excep-tion-Homolka’s colour base of fnchsine-t he quinoneimines them-selves had not until recently been isolated.Their existence wastherefore problematical and their properties were unknown. I n a seriesof memoirs which have been appearing a t intervals since 1902, underthe somewhat misleading title of ‘‘ Dibenzalacetone and Triphenyl-methane,”2 von Baeyer and Villiger describe the method of preparing anumber of these colour bases, and have sought by this means toestablish the structure of the compounds in question on a securefoundation. The question of how far these experiments have fulfilledtheir purpose scarcely falls within the scope of a report.The firstinvestigation was carried out with p-aminotriphenylcarbinol (I). Ifthe ethereal solution of the citrbinol is shaken with dilute hydrochloricacid, the orange hydrochloride begins to crystallise. It is regarded asthe hydrochloride of the carbinol (11). When this salt is suspended inether and saturated with hydrogen chloride, it dissolves, and after atime needles of the hydrochloride of the carbinol chloride are deposited(111).The latter salt loses a mo!ecule of hydrogen chloride when heated at100’ in a current of hydrogen, and leaves an orange-red powder, whichis distinguished from the carbinol chloride by its solubility in chloro-form. It is represented as the hydrochloride of the qninoneimine o rcolour base (IV), for which von Baeyer proposes the name fuchson-imine :Ber., 1904, 37, 4744.Ibid., 1902, 35, 1189, 3013 ; 1904, 37, 597, 2848, 3191124 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Fuchsonimine itself has not been isolated ; for if hydrochloric acidis removed from the hydrochloride (IV) by means of pyridine, it poly-merises and gives a dimolecular compound. But the amino- and di-amino-derivatives are more stable, and the phenylimino-bases, such asfuchsonphenylamine (V) and the bases of Dobner’s violet (VI), fuch-sine (VII), and diphenylamine blue (VZXI), can be isolated withoutdifficulty :/\/ \‘GH5 ‘GH5 v.NH/’\/ \NH,*C,H, C,H,VI.Fuchsonphenylimine. Aminofuchsonimine.(Dobner’s violet).NH/\II (I\/ 6/\ /\/ \PhNH*C,H, C6H4*NHPhDiaminofuchsonimine Diphen ylaniinofuchsonphenylamine/ \NH,*C,H, C,H4*NH5VII.VIII.(Honiolka’s colour base). (Diphenylamine blue).The method is to add caustic soda to a solution of the colour saltcovered with a layer of ether and to shake the mixture. The base dis-solves in the ether and can be separated by evaporating off the solvent.The colour bases have a brown or yellow colour and dissolve in theordinary indiff went organic solvents.They form colourless carbinolswith water, colourless and usually crystalline ethers with alcohol, anORGANIC CHEMISTRY -CYCLIC DIVISIONS. 125the original coloured salts with acids. No colour bases can be separatedfrom the salts of fully alkylated triaminofuchsonimines like crystalviolet, but the action of the alkali is probably to produce the ammoniumhydroxide, which changes to the carbinol or pseudo-base, such asHantzsch has shown to occur with methylacridine and other bases, towhich reference will shortly be made. This view is supported by thefact that sodium ethoxide forms with the coloured salt a colourlesscompound which has been identified as the ether of the carbinol.Von Baeyer and Villiger conclude from the results of their investigationthat the usual quinonoid formula of Nietzki is the correct expressionof the constitution of the triphenylme$hane colours.Without con-testing the main conclusions, Hantzsch opposes the view that thecolour base of fuchsine and allied colouring matters is an imino-com-pound. To understand Hantzsch’s position, it is necessary to take ashort retrospective survey of some of his previous memoirs. By acareful study of the changes which diazonium salts undergo whenacted on by solutions of alkalis, alkali cyanides, and sulphites,Hantzsch has formulated the theory that by virtue of the hydroxylions the dissociated diazonium hydroxide, which he regards as a trueammonium base, undergoes intramolecu1:ir change to the syn-diazo-compound or pseudo-ammonium base.2 The same tlieory has beenapplied to account for the colour changes, but more especially changesin electrical conductivity and ‘‘ abnormal neutrality ” of certiLincoloured salts and salts of colouring matters when alkali, potassiumcyanide, sulphurous acid, or a sulphite areadded to the solution. Justas the diazonium salts form syn-diazotates, diazocyanides, and diazo-sulphonates, as explained above, so the coloured salts of basic dyesgive colourless carbinols, cyanides, and sulphonic acids of the carbinoltype :RNCl RN RN a N fi -+ K0.N C d KO,S*NIIEvidence of these changes has been derived from the effect pro-duced on phenylmethylacridinium salts and allied compounds, and onsalts of triphenyl- and diphenyl-methanes and the azonium group ofBe?.., 1904, 37, 3434.’3 Ibid., 1899, 32, 3109, 3132 ; 1900, 33, 278126 ANNUAL REPORTS ON THE PROGRESS OF CEIEM’IS‘I’RT.colours by the addition of an alkali (caustic soda, baryta, or silveroxide).The changes may be represented as follows :Pheiiylmethylacridininm hydroxide. Pheny lmethylacridol.~:/--\:NR,-oH -+ \c(oH)/-\*NR,. / \-/ / \-/True amnioiiiuin base of Psenrlo-ammonium basc\ /-7 \ /-\ ‘c:’ \:NR,-OH )c(oH)/ \*NR,. triphenylmethane colours. or carbinol.The base, when first liberated from the salt of the colouring matter,frequently exhibits not only the colour of the original solution, but astrong alkaline reaction and a high conductivity of the order of causticpotash solution.This denotes the presence of the true ammoniumbase. More or less rapidly the colour fades, the alkalinity vanishes,the conductivity drops, and the insoluble and colourless pseudo-ammonium base is deposited.The basis of the colour, according to Hantzscb, is the ammonium ionof the salt or of the hydroxide, and not the imino-colour base ofHomolka and its congeners, which from Hantzsch’s point of view isan anhydride, bearing the same relation to the true base as gaseousammonia, NH,, to ammonium hydroxide, NH,OH. In support of thisview, he points out the striking difference in colour between Homolka’scolour base and magenta, and ascribes the magenta colour with whichthe colour base dissolves in water to the imino-compound uniting withwater and becoming, therefore, converted into the partly dissociatedammonium hydroxide.Many independent observations confirm theseviews. It has been shown, for instance, that just as the solution of acolour salt, after the addition of alkali, may f o r a time retain itscolour, so the reverse operation of adding an acid to a carbinol basemay at first produce no colonred solution. Dobnerl showed that thebase of malachite-green dissolves in dilute acid without colour until thesolution is heated. Lembrecht and Weil have prepared the colourlessoxalate and other salts of malachite-green and allied substances. Thiscolourless oxalate crystallises with 3 molecules of water which aredriven off on heating together with the carbinol water, and the metallicgreen salt is formed.These colourless compounds probably represent un-dissociated carbinol salts. Similar observations have been made on thebehaviour of solutions of the phenolphthaleins and have been explainedon similar grounds.3A number of interesting observations on the additive compounds ofthe rosaniline group have been made by Schmidlin.* H e finds thatAnnalen, 1883, 217, 252.Green and Perkin, Trans., 1904, 85, 398.Compt. rend., 1904, 138, 1508, 1709 ; 139, 506 521, 542, 602.Ber., 1904, 37, 3058ORGANIC CHEMISTRY-CYCLIC DIVISIONS. 127the black trihydrochlorides of pararosaniline and crystal-violet arestable and dissolve with the same colour as the monochloride in water,from which they are again precipitated by alcohol, He finds, moreover,that pararosaniline absorbs at the ordinary temperature and pressuretwo additional molecules of hydrochloric acid ; by lowering the tem-perature to - 70°, between 5 and 6 molecules are taken up, and at thetemperature of liquid air, S molecules are absorbed and the substanceis then quite colourless. As the acid escapes at the ordinary tempera-ture, the salt exhibits a series of colour changes, corresponding to thedifferent hydrochlorides, until it reverts to the black trihydrochloride,which, on heating, is further converted into a monohydrochloride.Theheptachloride is regarded by Schmidlin as the trihydrochloride of tetra-chlorocyclohexanerosaniline (I).The monohydrochloride, moreover, can absorb ammonia, and bylowering the temperature pararosaniline and crystal-violet will takeup 4 molecules of ammonia and become colourless (TI).Again, by thehydrolysis of rosaniline salts in acid solutions, 4 molecules of waterare added on and a new class of soluble, colourless derivatives, thet e t rah y drox ycycloh exaEe -rosanilines (I1 I), are obtained. The t ri hydro -chlorides of these tetrahydroxy-bases are stable at the ordinary tempera-ture, but lose 4 molecules of water at 50° and pass into the blacktrihydrochlorides. The author concludes from his researches that themolecule of rosaniline salts contains four aliphatic double bonds, thusconfirming with certain modifications, which cannot be discussed here,the quinonoid formula. These compounds are represented by thefollowing structural fomuls :NH,Cl I NH,ClA\&NH? Er’H2,lH\I/H// l\H NH2\H H/// \ N H 2 /\I/’ \NH3C1-C,H,*C*C,H,*NH3Cl.NH,*C,H,*CH* C,H,*NH,.I.11.NH,C1128 ANNUAL REPOK’I’S ON THE PROGRESS OF CHEMISTRY.Georgievicsl has introduced a new formula for the triphenyl-methane colours. I n the quinonoid formula, only one of the basicgroups in the mono-acid salts is united to the acid molecule, and thecolour is therefore made dependent on this one group. Now in a solutionof crystal-violet a series of colour changes, blue, green, and yellow,each with characteristic absorption bands, is produced by the successiveaddition of molecular equivalents of acid, and these colours and bandsappear to correspond to the neutralisation or removal of the coloureffect of successive amino-groups.Thus, the colour and absorptionbands of the green solution correspond to those of malachite-green,which contains only two dimethylamino-groups, whilst the yellowcolour and its absorption spectrum are the same when produced fromcrystal-violet by the addition of three, as from malachite-green by theaddition of two, molecular equivalents of acid. With more than thisamount of acid, the colour of both solutions is discharged. Thisindicates that each basic group plays a part in the colour effect of thewhole molecule, which Georgievics expresses by making each nitrogenatom quinquevalent and linked to its neighbour. The formulce are notreproduced, as they do not invite serious discussion.points out, Georgievics has completely ignored the recognised coloureffect of the auxochromic group, N(CH,),, which E. and 0.Fischer yearsago found could be neutralised by making the nitrogen quinquevalenteither by uniting i t with an acid, or transforming it into a quaternarycompound by union with an alkyl halide.Ton Braun Y has attempted to explain the structure of the di- andtri-phenylmethane colours by determining whether the nitrogen of theamino-group functions as a ter- or quinque-valent element. With thisobject he has employed cyanogen bromide, which has the property ofconverting the group NR, into N(CiN)R, wherein the nitrogen cannotincrease its valency. In derivatives of malachite-green of the formula(RR”*C,H,),CPh(OH), in which R’ represents (CN), (NO), (CS),(NHPh), the nitrogen exhibits no basic properties, and these compoundsdissolve in strong (not in dilute) hydrochloric acid with a red colour.Thedistinction in colour from that of malachite-green implies, according tothis author, a structural difference which is taken to confirm, althoughthe evidence is not quite convincing, the quinonoid structure of thecolouring matter.The coloured compounds which dibenzylideneacetone and triphenyl-carbinol give with acids have been the subject of various memoirs byvon Baeyer and Villiger,4 Straus,5 and Vorlander and Siebert withoutAs KaufmannZd. Furb. Text. Ind., 1904, 3, 37.Ber., 1904, 37, 633, 2670.Ber., 1904, 37, 3277.Ibid., 117.Vide ante, p. 123.Ibid., 3364ORGANIC CHEMISTR Y-CYCLIC DIVISIONS.129resulting in anything very definite in regard to their structure. hseries of triarylcarbinols has been obtained by Mothwurf 1 and certainhydroxytripl~onylcarbinols by Sachs and Thonet,z all of which possessthe same property of forming coloured salts. The colour reactionswith acids of unsaturated hydrocarbons like A’ ‘ 3-dihycirobenzenedescribed by Crossley 3 are significant as indicating how much stillremains unexplained of the relations which hold between the colourand the structure of a compound.Turning from theory to practice, by a survey of the patent lists forthe year, one is struck by the fact that side by side with the steadyproduction of new azo-colours there is no diminution in the number ofnew sulphur dyes.These new dyes, which comprise yellow, orange,brown, blue, violet, black, and also green shades (there is only one redsulphur dye), clearly find favour with the dyer. This is scarcelysurprising, for the majority of them are substantive colours, equalling,if not surpassing, in brilliancy and also in fastness to light and soapthe fastest of the organic dyes such as indigo, logwood, or anilineblack.The mechanism of the reaction whereby sulphur unites with basiccompounds, which was first explained by Bernthsen in the case ofmethylene blue, and afterwards utilised by Green in the production ofprimuline, has no doubt prepared the way for Vidal’s discovery of thesulphur dyes. Our present ideas about their structure are still very vagueand neither the simplicity of the method of production nor the varietyof materials which are employed in their manufacture has helped tothrow light on the subject. The process consists as a rule in fusingthe compound or compounds with sulphur and sodium sulphide at adefinite temperature, which may vary considerably in different cases.The materials are usually amino-derivatives of the aromatic series, ornitro-compounds, which, under the action of the sulphide, are reducedt o bases.The leuco-indophenols, the closely allied diphenylamine derivatives andsimpler benzene derivatives, like the diamines, amino- and nitro-phenols,which may pass into more complex groups on fusion, are all employedas well as sulphur compounds, such as thiosulphonic acids and thiocarb-amides. It seems generally admitted that the nucleus of the colour is athiazole ring, but more than this cannot yet be affirmed with anycertainty.It is interesting to note that Liebermann’s well-known “ nitroso ”-reaction has been turned to account in the production on a manu-facturing scale of compounds which have been identified as indophenols,Ber, 1904, 37, 3153.Trans., 1904, 85, 1419.2 Ibid., 3327.VOL. I. 130 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.and which as leuco-compounds can be used for the preparation ofsulphur dyes.The patents which have been applied for in connection with theproduction of artificial indigo, indoxyl, or indoxylic acid have usuallyhad reference to the method of fusion in attempts to increase the yield.At present, the raw material commonly used in the fusion is eitherphenylglycine, which is A comparatively cheap product but gives a smallyield, or phenylglycine o-carboxylic acid, which is more costly, but givesa larger output. Caustic potash, which was originally used, has beenreplaced wholly or in part by caustic soda, the alkaline earths andsodamide, and even nitrides, alkali carbides, and hydrogenides havebeen proposed for the purpose.Numerous patents have also been taken out for the manufactureof halogen derivatives of indigo, colours chiefly of blue and greenfihades from anthraquinone and yellow acridine colours. A new classof colouring matters which promise t o be of some importance hasbeen obtained by Konig by combining pyridine cyanogen bromidewith aromatic amino-compounds. The new colours vary in shade fromydow through orange and red to violet. Besthorn and Ibele2 alsodescribe a group of new dyes derived from quinoline-a-carboxylic acid.Miethe and Book3 publish an investigation on the cyanine colours, thetechnical value of which has greatly increased since their introductioninto photo-chemistry and colour photography. The colour called (‘ ethylred,” which is obtained by the action of 2 molecules of quinolineethiodide on 1 molecule of quinoline ethiodide in presence of causticpotash, has been assigned the following structure :An ingenious application of colour reactions to physiological in-vestigation is described by Ehrlich and He13er.~ They find that Witt’sP-naphthaquinonesulphonic acid is highly reactive, forming a series ofcoloured products with aromatic bases as well as with a variety ofother substances, including peptone, tyrosine, and uric acid. Thecompound with dimethyl-p-phenylenediaminethiosulphonic acid readilyJ. pr. Chew&., 1904, [ii], 69, 105 ; 70, 19.Ibid., 2008. 2 Bey., 1904, 37, 1236.4 Zeit. physiot. Chevt., 1904, 41, 379ORGANIC CHEMISTRY-CYCLIC DIVISIONS. 131loses sulphurous acid and gives a coloured thiazine derivative. Wheninjected into a rabbit, the skin and other parts assume characteristiccolours. Another application of Witt’s compound is in detecting thepresence of aniline in the body by painting sections of the differentorgms with a solution of the reagent and observing the colour whichdevelops.J. B. COHEN.K

ISSN:0365-6217    

DOI:10.1039/AR9040100084

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

STEREOCHEM ISTRY.DURING the past year but few modifications have been suggested in thecurrent views regarding the arrangement of atoms in space; the mainactivity in this direction has been in connection with the configurat,ionof quinquevalent nitrogen compounds, a subject in which it can scarcelybe claimed that any general agreement of opinion has been reached.E. Erlenmeyer, jun., and A. Arnold have expressed the view’ thatin addition to cis- and trans-isomerism of the well-recognised fumaroidand maleinoid types a third kind of stereoisomerism is sometimes to beobserved; they derive this type theoretically by supposing one of thegroups CR’R’ in the ethylene derivative, CR’R”:CR’R, to be rotatedat 90’ to the other (I or 11) so as to give rise to the twoenantiomorphously related configurations, I11 and IV.They considerPh PhH HH*g*Ph H* G-PhH*C*CO,H HO,C* C*H H+CO,H H O ~ + - H .I. 11. 111. IV.that the plane configurations I and II represent respectively iso-cinnamic and cinnamic acids, whilst aZZocinnttmic acid, which forinshemihedral crystals, is the externally compensated mixture having thesolid configurations I11 and IV. P. Pfeiffer has also discussed theapparent discrepancies between the ordinary views as to the configura-tion of carbon compounds and certain facts relating to the changes ofmaleinoid and fumaroid compounds.2 He suggests that the configura-tion of saturated ethane derivatives is one in which the two ethanecarbon atoms occupy the centre of an octahedron, at the six apices ofwhich are situated the six groups attached to the pair of carbon atoms ;he thus discards the idea that valency acts in definite directions, andalso gives up the ordinary conception of double and triple bonds.Theconfigurations at which Pfeiffer arrives by starting from the aboveassumption are not very dissimilar from those which Barlow hasderived on purely crystallographic grounds, and those which Wernerhas suggested for explaining the isomerism of many inorganic com-pounds.1 iln71cLle11, 1904, 337, 329. Zeit. physikal. Chern., 1904, 48, 40STEREOCHEMISTRP. 133The question of the primeval origin of optically active substanceshas been reopened in a new way by A. Byk,l who recalls an oldexperiment of Jamin’s, which indicates that terrestrial magnetismcauses the partially plane polarised light reflected from such surfacesas that of the ocean t o become partially circularly polarised.In thecircularly polarised light thus produced, one component-say, d-light-predominates on the earth’s surface. Byk then confirms the observa-tion of Cotton 2 that d circularly polarised light is differently absorbedby copper ammonium d- and Z-tartrates. The preponderance of d-lighton the e:irth’s surface must therefore be more favourable to thepersistance of one optically active component of racemic acid thanto the other.inconnection with the problem of ‘( asymmetric synthesis.” On heatingthe acid brucine salt of the potentially inactive methylethylmalonicacid, CMeEt(CO,H),, until the evolntion of carbon dioxide is complete,and liberating the valeric acid thus produced, the latter was found tocontain a considerable excess of the Z-isomeride, CHMeEt*CO,H.This is claimed as being the first recorded case of a true “ asymmetricsynthesis ” ; to this view, however, Cohen and Patterson have objectedthat the brucine may separate from the original solution in methyl-ethylmalonic acid with one optically active ion, CMeEt(C‘O,H)*CO,-,of the latter, and that Marckwsld’s synthesis should then be regardedmerely a s an application of one of the three Pasteur methods ofresolution.To this objection, Marckwald replies, and apparentlyeffectively, that the whole of the methylethylmalonic acid used wasconverted into the brucine salt.I n connection with the question of asymmetric synthesis, A.McKenzie shows that on treating menthyl benzoylformate,PhCO*CO*O*C,,,H,,, successively with magnesium methyl iodide, water,and acid, a mixture of externally compensated and Z-phenylmethyl-glycollic acids, CMePh(OH)*CO,H, is obtained ; the production of anasymnietric carbon atom in ths acidic part of the menthyl benzoyl-formate molecule is so influenced by the presence of the optically activementhyl group that the acidic group becomes optically active.Asimilar result is obtained on treating menthyl benzoylformate withmagnesiuni ethyl bromide. Further, on reducing Z-menthyl benzoyl-formate, slightly more Z-menthyl Z-mandelate than d-mandelate isproduced.M. A. Ragusin has made the important observation that the distil-lates from both Russian and American petroleum are l~vorotatory ;A result of great interest has been obtained by W, MarckwaldBer., 1904, 37, 4696 ; Ztit. physikal.Chena., 1904, 49, 641.Ann. Chim. Phys., 1904, [vii], 8, 373.Ber., 1904, 37, 349. Trans., 1904, 85, 1249134 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the rotatory powers recorded are small, and the highest values areobtained with the less volatile fractions. These results recall a remarkmade by P. Walden: some years ago to the effect that if optically activepetroleums could be found the geological dispute as to the origin ofpetroleum would be ended ; the optical activity seems to indicate thatpetroleum is necessarily of animal or vegetable origin.E.Jungfleisch has recorded2 the results of a number of experimentsfrom which he concludes that Z-lact,ic acid undergoes hydrolysis morereadily than its enantiomorphously related isomeride. The contradic-tion of theory thus introduced is perhaps counterbalanced by theobservations of A. Piutti 3 that the recorded statement that the crystal-line d- and I-P-asparagines have different densities is erroneous.A series of determinations of the speed of inversion of cane-sugarby d- and I-camphorsulphonic acids has been made by R. J. Caldwellwith the object of ascertaining whether these enantiomorphously relatedacids effect the hydrolysis of the optically active sugar a t the same orat different speeds. Neither in the case of cane sugar nor of milksugar could any difference in the speed of hydrolysis be detected.An interesting discussion as to the optical functions of theasymmetric carbon atoms in the closely related alkaloids Z-ecgonine,d-+-ecgonine, and anhydroecgonine has been contributed by J.Gadamerand T. Amenomiya; 5 they conclude that the three alkaloids have thefollowing configurations :CH,. (d) SH-( Z)FH* CO,H I ?Me (Z)FH*OH I YMe (d)QH*OHUH2-(Z) C H-CH,2- Ecgonine. d-+ Ecgonine.CH,* (d)yH-(Z) yH*CO,HCH,-(Z) C H-CH2I TMe GHCH,-(Z)C H-CHAnh yciroecgonine.This result follows mainly because (1) the same anhydroecgonine isproduced from both Z-ecgonine and d-+-ecgonine, and (2) on subjectinganhydroecgonine to treatment with caustic potash, which convertsI-ecgonine into d-$-ecgonine, its optical activity remains unchanged.During the past year, no methods of a novel character have beendevised for resolving externally compensated substances into theirenantiomorphously related components.Those variations of the secondPasteur method of resolution which have been introduced duringNaturu;isse.lischa~~l~ches Rtmdschau, 1900, 15, 15.Covapt. rend., 1904, 139, 203.Proe. Boy. Xoc., 1904, 74. 184.Gnxzettu, 1904, 34, [GI, 36.Arch. Pharm., 1904, 242, 1STEREOCHEMTSTRY. 135recent years have, however, been somewhat extended. Thus, MoKenzie,continuing his former work with Marckwald on the esterificatioiimethod of resolving externally compensated acids, shows that whendZ-mandelic acid is heated with I-borneol the residue of unesterifiedacid contains an excess of the I-acid ; 2 the mixture of esters also yieldsa preponderance of I-mandelic acid.This result is interpreted asmeaning that d-mandelic acid is esterified more rapidly than theI-isomeride by Z-borneol, since the I-acid remains unesterified ; the factthat the mixture of esters yields an excess of I-mandelic acid onhydrolysis is attributed to the acid, in I-bornyl d-mandelate, undergoingoptical inversion during the formation of the ester more rapidly thanis the case with I - bornyl I-mandelate. On fractionally hydrolysingZ-bornyl dl-mandelate with caustic pot ash, the first fraction hydrolysedcontains an excess of d- over I-mandelic acid, whilst the last fractionwhich undergoes hydrolysis gives cll- or inactive mandelic acid ; I-bornyld-mandelate thus appears to be more readily hydrolysed than I-bornylI-mandelate, although the latter is the more easily formed.On hydrolysing I-bornyl dl-mandelate with more than one equivalentof alcoholic potash, inactive acid is produced; by treating the esterwith much less than one-half an equivalent of potash, d-mandelic acidis formed, whilst on using more than one equivalent of caustic potasha salt of I-mandelic acid is produced.I-Mandelic acid undergoes com-plete optical inversion when heated with 13 per cent. caustic potashduring several hours on the water-bath; this fact is interesting inconnection with the observation of Kipping 3 that d-msndelic acid some-times yields externally compensated pheiiylchloroacetic chloride withphosphorus pentachloride, and of Easterfield 4 that I-mandelic acid givesthe same externally compensated acid with fuming hydrochloric acida t 100'.I-Menthyl dl-mandelate cannot be resolved into its componentesters by crystallisation from light petroleum, and is thereforedescribed as partially racemic.The resolution of externally compensated primary bases by combina-tion with an optically active aldehyde has been further studied byE. Erlenmeyer, jun., and A, Arnold.5 On condensing dl-isodiphenyl-hydroxyethylamine with i-helicin, two substances of the constitutionPh*yH*OHPh*CH*N:CH.C,H:,*O*CGH,lO,are obtained ; these have [.ID - 6.43" and - 43*60°, and on hydrolysisyield d- and I-isodiphenylh ydroxyethylamines having [.ID + 109.72'and - 108.33' respectively in alcoholic solution.Neville and Pickard have prepared I-menthylcarbimide and ForsterBer., 1899, 32, 2130.Trans,, 1903, 83, 1005.Amden, 1904, 337, 307.Ibid., 1904, 37, 378.Tram., 1904, 85, 685.'$ Ibid., 1891, 59, 72136 ANNUAL REPORTS ON THE PROGRESS OF CHEMIS'L'RY.and Atwell's d-bornylcarbimide ; they suggest the application of thesetwo substances to the resolution of externally compensated hydroxy-compounds and bases.Forster and Atwell, however, indicate81 thatbornylcarbimide reacts too sluggishly with hydroxy- and amino-compounds to render it useful in the suggested connection. Thewriter may perhaps be allowed to point out that d-butylcarbimide,which forms the main constituent of oil of spoonwort, could certainlybe substituted with success for the bornyl- and menthyl-carbimidesmentioned above.A number of externally compensated acids have been resolved intotheir optically active components during the past year.A new methodfor resolving fermentation lactic acid has been devised by E. Jung-fleisch depending on the crystallisation of the quinine salt underspecial conditions; although the carrying out of the new methodsuggests several points of theoretical interest, i t does not appear tooffer any advantages over the method devised by Purdie andWalker .3Morrell and Bellars have resolved P-methylglyceric acid,CHMe(OH)*CH(OH)*CO,H,by crystallisation with quinidine ; the salt Z-B LA. is the least solublein water, and the crystalline Z-acid separated therefrom gives[a]= - 13.51' in aqueous solution.The salt Z-B d-A could not beobtained in a pure state, but by applying the fact that the barium saltof the inactive acid is insoluble in alcohol, whilst that of the activeacid is somewhat soluble, the pure barium salt of the d-acid wasisolated,Externally compensated p-methoxymandelic acid can be readilyresolved into its d- and Z-components ([a],, in water, +146*1" and- 146.2') by crystallisation with cinchonine ; the specific rotatorypowers are but slightly less than that of mandelic acid ( [ a ] , + orH. B. Hill and F. W. Russe have also resolved P-dihydrofurfurane-act'-dicarboxylic acid by the crystallisation of its cinchonine salts ; inone-half per cent.aqueous solutions, the acids have the specific rotatorypowers of + or - 500'. Owing to the possibility of this resolution, theauthors are able t o prove that the P-dihydro-acid is externally com-pensated, and that the so-called a-acid is the potentially inactiveisomeride.Phenylisoparnconic acid has been resolved by crystallisation withstrychnine ; 7 the optical antipodes give [a], + 14.72" and - 14.51" in- 156.4').Tra7ts., 1904, 85, 1188.Trans., 1895, 67, 616.E. Know, Ber., 1904, 37, 3172.iJ (:ompt. retid., 1904, 139, 56.Ibid, 1904, 85, 197.(i Be?.., 1904, 37, 2538.7 R. Fittig and P. Jehl, An?zaZeit, 1904, 330, 292STEREOCHEMISTRY. 137alcoholic solution, whilst in acetic acid solutions the signs of therotatory powers are reversed.I'enicillium glaucum destroys theI-acid more rapidly than its isomeride, so that the latter can be readilyisolated by aid of the mould. Phenylparaconic acid,Ph*CH-CH*CO,HI >OH, 9 0-cohas also been resolved by crystallisation with strychnine; the com-ponent acids give [a], + 64.33" and - 65.33" in alcoholic solution.C. Neuberg and M. Silbermannl have set a t rest the doubtswhich prevailed as to the optical constants of the d- and I-glyceric acidsOH*CH,*CH(OH)-CO,H, by resolving the externally compensatedacid by crystallisation with brucine ; brucine I-glycerate separates a sthe least soluble salt, and from it barium 1-glycerate of [a], - 17-34'was obtained. The barium d-glycerate from a!-glucuronic acid gave[a], + 17.1'.state that ma-methylethylhydracrylicacid, OH*CH,-CRleEt*CO,H, cannot be resolved into its opticallyactive components by crystallisation with quinine or cinchonine.8.Condelli3 finds that the optimum temperature for the decom-position of racemic acid by AspergiEEus niger ia 35'; he shows thatd-tartaric acid is most readily destroyed by the organism at low tempera-tures, whilst the Eisomeride is the more readily attacked at highertern pe r atur es .A. Pictet and A. R ~ t s c h y , ~ having prepared synthetically tetra-hydronicotyrine and shown it to be identical in constitution withnicotine of natural origin, resolved it into its optically active com-ponents by crystallisation with d-tartaric acid. The salt I-B d - A isthe least soluble, and from it Enicotine ([a], - 160*93"), identicalwith the naturally occurring alkaloid ([a], - 166-39"), is separated.The hitherto unknown enantiomorphously related isomeride, d-nicotine([a], + 163.1 5'), was also isolated.Physiological experiments madewith the two isomerides lead to the interesting result that I-nicotineis about twice as poisonous as d-nicotine; the injection of the I-base isextremely painful to the animal, whilst that of the d-isomeride seemsto cause no pain.Optically active homologues of benzene have been prepared byA. Klages and R8. S a ~ t t e r . ~ Magnesium d-amyl iodide acts on benz-aldehyde yielding dhexenylbenzene, CHPh:CH*CHMeEt ([a], + 50-3'),which, on reduction, gives d-hexylbenzene, CH,Ph*CH,*CHMeEtE. E. Blaise and L.MarcillyBer., 1904, 37, 336.(mxzctta, 1904, 34, 86.]bid., 649.BUZZ. Soc. chim., 1904, [iii], 31, 317.Be?.., 1904, 37, 1225138 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.([a], + 172"); the latter substance could not be caused to undergo opticalinversion. The authors found difficulty in preparing d-amyl alcohol by themethod of Marckwald and McKenzie, and the former has thereforegiven further directions for applying the method, H e also remarksthat the difficulty of preparing pure d-amyl alcohol is partly due to theinteresting fact that all the known crystalline derivatives of d-amyland isoamyl alcohols form solid solutions ; thinking that this tendencytowards the formation of solid solutions might be sufficiently diminishedif large substituting groups were introduced into the molecules of themixture of alcohols, he has prepared the urethanes.isoAmylurethaneand d-arnylurethane, however, still form solid solutions, although thetendency to do so is less than with the previously investigated solidiso- and d-amyl compounds, Thus the d-urethane is insoluble in theiso-compound, but the isourethane is fairly soluble in the d-isomeride ;the two isomerides thorefore cannot be separated by fractional crystar-lisation.Marckwald finds that the solubility curve of mixtures of the bariumsalts of d-amyl- and isoamyl-sulphuric acids is quite continuous, andhas found an analytical expression representing the curve. He alsogives a good method of preparing d-valeric acid ([ a ] D + 8.75") by theoxidation of d-amyl alcohol with chromic acid, and has prepared purecl-amyl iodide ([ + 5.64O) arid bromide ([a], + 3*ES0).d-Amplamine([a], - 5-86'), prepared from d-amylphthalimide, is remarkable in thatits hydrochloride is optically inactive to sodium light. Marckmaldhas also prepared the simplest possible optically active paraffin, namely,d-methylethylpropylmethane, CHMeEtPr, in a pure state ([ a ] D + 9.5")by the interaction of d-amyl iodide, ethyl iodide, and sodium.W. Meyerhoffer discusses 2 the equilibrium conditions attending theseparation of the components of an externally compensated acid byPasteur's method of crystallisation with an optically active base. Since,in such a crystallisation, three salts are capable of formation, namely,the salts, d-B d-A, d-B Z-A, and the partially racemic salt, 2d-B dl-A,there should be three ranges of temperature distinguishable, corre-sponding with the separation from the solution, side by side, of thetwo solid salts, (a) cl-B d-A, and d-B Z-A, (b) of the less soluble of thetwo latter and the partially racemic salt, and (c) of the partiallyracemic salt alone.Power and Tutin 3 have separated a Z-quercitol,having [a], - 73*9", from the leaves of Gymnemn sylvestre.Eightoptically active isomerides of this constitution should exist, and theIbid., 2604. Ber., 1904, 37, 2088. a Trans., 1904, 85, 624STEREOCHEMISTRY. 139one now described is not enantiomorphously related to the cl-quercitolalready known, because this has [.ID t-24-16'. The two sugarsfucose and rhodeose Lave been shown to be enantiomorphously relatedby E.VotoCek.1A good deal of work has been done on the actual determination ofrotatory powers and on the deductions to be drawn therefrom.A. Rosenheim and H. Aron find that the rotatory power of d-tartaricacid is quadrupled by addition of a caustic potash solution of stannicchloride, and attribute this to the formation of a complex acid ioncontaining tin and the tartaric acid radicle ; the stannitartrates thusformed were isolated by Henderson, Orr., and WhiteheadV2 H. Gross-mann and 11. Pijtter have examined 3 the effect of change of tempera-ture on the rotatory powers of ammonium molybdanylbimalate,MOO,( C,H,O,*NH,),, in aqueous solution. I n 3-12 per cent.solutions of malic acid to which the corresponding amount of ammo-nium molybdate has been added, the specific rotatory power attains amaximum ~ a l ~ e at 35" ; above and below that temperature, the rotatorypower.diminishes. The same kind of change of rotatory power until amaximum value is reached during continous rise of temperature hasbeen previously observed to occur by P. F. Frankland and F. M.Wharton in the case of diethyl diben~oyltartrate.~the rotatory powers of methyl, ethyl,and n-propyl &tartrates at temperatures from 10-100", and findsthat the comparison of the data a t the same temperatures indicatesbut little relationship. By extrapolation, however, it is shown thatthe esters should be optically inactive for the D-line at Oo, - 3 4 O , and- 60' respectively, and it is suggested that these are '' correspondingtemperatures " for the optical properties of the substances, Generally,also, the temperatures To, To - 3 4 O , and To - 60°, are correspondingtemperatures for the three esters, To being the temperature on theabsolute scale. This view is supported by the result that the ratios ofthe molecular rotatory powers of the esters are nearly constant a tcorresponding temperatures.At corresponding temperatures, theethyl d-tartrate gives [MI, about 2.1 times that of the methyl ester,and the [MID of n-propyl tartrate is 1.41 times that of the ethyl salt.contributed a mass of valuable experi-mental data including values of the rotatory powers of sodiumtartrate, potassium tartrate, potassium methyl tartrate, potassiumethyl tartrate, potassium n-propyl tartrate, and of methyl, ethyl, andn-propyl tartrates in aqueous solutions at series of temperaturesbetween 10" and looo, and values of the molecular solution volumesPatterson has determinedThe same worker has alsoBe?.., 1904, 37, 2859.Ber., 1904, 37, 84.Ibicl., 1904, 85, 765.TrcL'ns., 1899, 75, 555.Tyatas., 1896, 69, 1583,IbicZ., 1116 and 1153140 ANEUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of methyl, ethyl, n-propyl, potassium methyl, potassium ethyl, andpotassium n-propyl tartrates.A distinct connection is shown toexist between the gram-molecular contractions on solution and thechange in molecular rotatory power set up by such solution. Therotatory powers of the alkyl tartrates are increased by solution inwater, and a rapid diminution occurs on heating the dilute solution ;in the solvent-free state, the rotatory powers of the esters increase asthe temperature rises.the rotatory powersof the methyl and ethyl esters of the di-o-, -m-, and -p-nitrobenzoyl-tartaric acids at temperatures between 15" and 180O.The intro-duction of nitro-groups into the dibenzoyltartrates in para- or meta-positions greatly increases the molecular rotatory power ; theintroduction of nitro-groups into the ortho-position diminishes themolecular rotatory power above 130", but as the temperature fallsthe rotatory power increases so rapidly that ethyl o-nitrobenzoyl-tartrate has a higher rotatory power a t 15" than has its para-iso-nieride.The rotatory powers and dispersions have been determined byE.Wassmer and P. A. Guye 2 of a large number of aciiic derivativesof ethyl malate. I n this series, the specific rotatory power diminishescontinuously whilst passing from ethyl propionylmalate to ethyldecoglmalate, but the molecular rotatory power attains a maximumin ethyl butyrylmalate. A number of alkyl lactates were alsoexamined, and in the latter series the specific rotatory power attains amaximum value in octyl lactate.As a supplement to the work of Briggs and Cohen 3 on the I-menthylesters of the six dichlorobenzoic acids, J. R. Cohen and H. S. Raperhave examined the I-menthyl esters of the ten chlorobroniobenzoicacids. The values of [MI, for the corresponding chlorobromo- andthe dichloro-esters are of the same order of magnitude.The molecularrotatory power of I-menthyl benzoate ([ MID - 236.3') decreases mostwhen the substituting halogen atoms are ortho- to the carboxyl group,and decreases least when the halogen atoms are meta- to the carhoxyl.The rotatory powers of the I-menthyl 0-, m-, and p-iodobenzoates ([MID- 246O, - 2345", and - 241.2" respectively) are not in the same orderas those of the corresponding chloro- and bromo-benzoates given byCohen and Briggs (Zoc. cit.) and by Tschugaeff.4W. Urban,5 has prepared and determined the rotatory powers of along series of alkylated d-butylthiocarbamides and d-butylcarbamidesby the action of primary and secondary amines on d-butylthiocarb-P.F. Frankland and J. Harger have studiedTrans, 1904, 85, 1571,T~niis., 1903, 83, 1213.Arch. Pharm., 1904, 242, 51.J. Chiwz. ph)ys., 1903, 1, 257.Ahsty., 1903, 84, ii, 2STEKEOCHEMISTRY. 141imide, CS:N*CEIl\lleEt.NHR*CS*KH*CHMeEt, NR,*CS*NH*CHMeEt, andR:N*CS*NH*CHMeE t,and the corresponding types in which sulphur is replaced by oxygen.I n spite of the large changes which are caused throughout the seriesin the mass of the group attached to the butyl radicle, the molecularrotatory powers do not differ greatly ; large variations in the rotatorypower attend the change of solvent from alcohol to c'iiloroform.J. W. Walker found1 that the complete hydrolysis of amygdalinicacid yields externally compensated mandelic acid; H.D. Dakin nowshows that, on fractional hydrolysis with baryta, d-mandelic acid isfirst liberated, whilst Z-mandelic acid preponderates in the hydrolysisproduct of the final fraction. Amygdalin is a maltoside of Z-mandelicacid, and on partial hydrolysis yields amygdalinic acid, which is amixed glucoside of d- and Z-mandelic acids. By agitating amygdalinwith baryta solution, Dakin has converted it into an isomeride,isoamygdalin ([.ID - 47*6"), which yields both d- and Z-mandelic acidson complete hydrolysis. Walker had previously suggested that somesuch partially racemic substance as this is an intermediate product inthe conversion of amygdalin into amygdalinic acid.The substances examined were of the tIpesBowack and Lapworth find that Z-menthyl cyanoacetate,C,oH1,O*CO*CH,*CN,and several of its derivatives do not exhibit mutarotation; the specificrotatory power of these substances does not iifford evidence of changingmolecular structure, although such evidence is found in the muta-rotation of derivatives of E-menthyl a~etoacetate.~ Only slight muta-rotation was observed by Hann and Lapworth5 to occur amongst theZ-menthyl alkylideneacetoacetates.Lowry has shown6 that the equilibrium proportion in which twodynamic isomerides exist in a solution may be ascertained by saturatinga solvent with the stable form, and at once determicing how much ( a )has gone into solution, then allowing the solution to remain in contactwith the stable form until equilibrium has been established betweenthe dynamic isomerides present in the solution, and again determiningthe composition (b) of the solution; the ratio cc/(b-a) representsapproximately the proportion in which the isomerides are present inthe equilibrium solution.I n the case of solutions of nitro- andrr-bromo-camphors, the normal and +-forms are in equilibrium whenpresent in the solution in the ratio 5 : 1 approximately. On applyinga similar method to glucose and galactose, Lowry found7 that theTrans., 1903, 83, 472.Ibid., 42.]bid., 1904, 85, 49.7 Ihid., 1551.Ibid., 1904, 85, 1512.Zbid., 1903, 83, 1117.Ibid., 1541142 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.proportion of a-sugar present in the equilibrium solution decreases asthe amount of water in the solvent increases ; thus in methyl-alcoholicsolution one-half of the sugar is present as the a-form, whilst in themixture EtOH,H,O, only 40 per cent.is of the a-form. It is suggestedthat the a- and @forms are present in about equal proportion in thesolutions, but that in the aqueous solutions a third hydrated andintermediate form is produced, thus :CH,*OH CH,*OHQH-OHCH,*OHa-Glucose hydrate. GIucose aldehydrol. @-Glucose hydrate.E. F. Armstrong and Arupl have made careful determinations ofthe velocities of hydrolysis of a- and /3-glucose pentaoetates, P-galactosepentacetate, and sucrose pentacetate by potash. The results obtainedare very concordant, and indicate that the velocity and course of thehydrolysis of a- and P-glucose acetates are identical, but that galactosepentacetate hydrolyses considerably more rapidly. The values obtainedfor octacetylsucrose are of peculiar interest, in that they indicate nodistinction between the behaviour of the acetyl groups in the sucrosederivative and the glucose from which it is derived.The velocitycoefficient in each case diminishes as the time increases, indicating thatthe acetyl groups do not all separate at the same rate. Determinationsof the velocity of hydrolysis of the tetracetates of a- and P-methyl-glucosides and of a- and P-methylgalactosides show that all foursubstances are hydrolysed at the same rate; this is important, in viewof the fact that in these isomerides the scetyl groups occupy similarpositions in the molecules. The interconversion of the d-glucose Q-and /3-pentacetates has been studied by C.L. Jungius.2T. Purdie and J. C. Irvine have shown3 that on methylatingtetramethylglucose, tetramethyl-P-methylglucoside (m. p. 42-43O ;[a],, in water, - 11.6') is the main product, a liquid stereoisomerictetramethyl-a-methylglucoside ([ aID, in water, + 147.4") being formedin small quantity. The P-glucoside contrasts with the a-isomeridein its more rapid hydrolysis with acid and by being hydrolysed byemulsin.Tetrametbylglucose exhibits mutarotation; the a-form (m. p. 88-89";[a],, + 100.8O) is produced by repeated crystallisation from petroleum,Tq-ans., 1904, 85, 1043.2 Proc. K. Akad. Wetensch. Anzsterdanz, 1904, 6, 779.3 Trans., 1904, 85, 1049STEREOCHEMISTRY.143and on heating above its melting point yields the p-form ([a]D + 73*1°),which on preservation reverts t o the umodification. The form stablein solution ([a]. + 83.3') appears t o be an equilibrium mixture of thetwo. Since mutarotation is also observed in benzene and carbontetrachloride solutions, the assumption of ionisation or the formationof hydrates is not essential for explaining the phenomena.R. Behrend and P. Roth have observed also that d-glucose shows1mutarotation in pyridine solutions, and state that the specific rotatorypower of d-glucose in pyridine is at first [aID + 138*88O, but that duringthe lapse of 24 hours this value falls too + '71.17'; they conclude thatthis fact excludes the possibility of the mutarotation being due to theformation of hydrates.obtain a liquid tetramethyl-a-methyl-galactoside ([a],, in water, + 143.4') by the silver oxide method ofalkylating a-methylgalactoside ; on hydrolysis with hydrochloric acid,i t yields a liquid tetramethylgalactose, which exhibits mutarotation inaqueous, alcoholic, and benzene solutions.On methylation, tetra-methylgalactose yields stereoisomeric tetramethyl-a- and -P-methyl-galactosides ; the a-isomeride is the main product when methyl alcoholand hydrogen chloride are the methylating agents, whilst alkylationwith silver oxide and methyl iodide gives mainly the P-isomeride.The latter is crystalline (m. p. 44-45O) and is more readily hydrolysedthan the a-isomeride with dilute acids or emulsin.Tutin and Kipping demonstrate the probability that the so-calledd- and Z-menthones produced from menthol are stereoisomeric, but notenantiomorphously related.They are interconvertible by passagethrough an enolic form, thus :J. C, Irvine and A. CameronPrS PrSH2C CH2\/A C ( - )H MeIC/\\/H2F ?-OHH2C CH2C( - )/\H MeZ-Menthone. Enolic form.H2C CH,\/ A? H Med-Menthone or2- isornenthone.From Z-menthone, by reduction of the oxime or by heating withammonium formate, a mixture is obtained of the four possible stereo-isomeric bases containing three asymmetric carbon atoms, one ofwhich remains of fixed sign. The bases are named Z-menthylamine([ aID - 6 1 9 O ) , Z-neomenthylamine ([a],, - 17*4"), Z-isomenthylamineAlannlen, 1904, 331, 359.Trans., 1904, 85, 1071. Ibid., 65144 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.([ a]D + 22.7'), and Fisoneomenthylamine ([ - 3*8O), the numbersquoted being the specific rotatory powers of the corresponding benzoylderivatives. The separation of the components of the basic mixturewas effected by crystallisation of the hydrochlorides, bromocamphor-sulphonates, camphorsulphonates, and the benzoyl and formylderivatives.Considerable activity has prevailed during the past year in connec-tion with the stereoisomerism of derivatives containing tervalentnitrogen and of quaternary ammonium derivatives. H. 0. Jones haspublished 1 an exhaustive summary of our previous knowledge of thestereochemistry of nitrogen.A. Ladenburg 2 has continued his study of the new kind of stereo-isomerism of tervalent nitrogen to which he has previously referred.3/? H,C CH,He resolves synthetic stilbazoline, 1 I , into itsH2c C<CH,.CH,Ph '\/NHoptically active components by the aid of d- and I-tartaric acids, andobtains the d- and I-stilbazolines, having [.ID + 12.1 6' and - 11 *5" a t 20'.He then heats I-stilbazoline at 300°, and finds that i t is convertedinto a mixture of d- and I-stilbazolines and a new isomeride, I-Go-stilbazoline.The resolution of the mixture is effected by first removingthe I-stilbazoline as its d-hydrogen tartrate, and converting the baserecovered from the residue into its neutra,l I-tartrate, when I-60-stilbazoline I-tartrate separates. Salts of I-isostilbazoline were alsoisolated by another method of separation depending on the use ofd-camphorsulphonic acid, and in each case the purified salt yieldedI-isostilbazoline of [ .II, - 5.7'.From this fact and from differencesobserved between the behaviour of the corresponding salts of the stil-bazolines and I-isostilbazoline, Ladenburg concludes that the latter isnot a mixture, but a true stereoisomeride of stilbazoline.Kipping and Salway 4 refer to the discrepancies between the theoryof Hantzsch and Werner,5 which explains the isomerism of the oximesby assuming that the three valency directions in tervalent nitrogendo not lie in one plane, and the failure of previous attempts to resolvebases in which three different groups are attached to the tervalentnitrogen atom ; they again point out that the latter experiments areindecisive owing to the possibility of a change in the valency directionsattending the conversion of ter- into qiiinque-valent nitrogen and viceBrit. Assoc.&ports, 1904.Ibid., 1895, 28, 854.Ber., 1890, 23, 11.Ber., 1904, 37, 3688.Trans., 1904, 85, 438STEREOCHEMISTRY. 145versd. They treated cl-hydrindamine, Z-methylhydrindamine, Z-menthyl-amine, and Z-phenethylamine with d-benzylmethylacetic chloride, and ineach case obtained but one acetyl derivative of the primary or secondarybase ; if the three nitrogen valency directions do not lie in one plane,the production of stereoisomerides would be anticipated. It is there-fore conclirded that the three valency directions of tervalent nitrogenlie in the same plane.It is pointed out that on treating an optically ipactive base with anexternally compensated acid chloride, only one acidic derivative shouldbe formed if the original base is potentially inactive, whilst two iso-merides are capable of formation if the base is externally compensated.Thus, dl-hydrindamine yields two isomeric acidic derivatives withdl-benzylmethylacetic chloride, whilst methylaniline, p-tolnidine, benzyl-aniline, and phenylhydrazine yield but one product in each case.Somemonths later, E. Mohr describedl the same method for ascertainingwhether a base is potentially inactive or whether i t is externally com-pensated.CH,Ph*CHEt*COCl + NH,-CHPhMe =CH,Ph-CHEt*CO*NH*CHPhRle + HCl,using externally compensated materials, he found that two isomericcompounds were formed ; this is, of course, due to the potential opticalactivity of both the reacting substances.Externally compensated hydrindamine may be resolved by treatmentwith d-benzylmethylacetic chloride ; the least soluble of the two pro-ducts of the reaction is d-benzylmethylaceto-d-hydrindamide.Similarly,dZ-a-phenethylamine is resolvable by the aid of the same acid chloride,and d-benzylmethylnceto-kphenetliylimide is readily separable from theproduct. I n these two cases, it was found impossible to regenerate theoptically active bases by the hydrolysis of the acidic derivative.The question as to the distribution in space of the three valencydirections of a tervalent nitrogen atom has been also dealt with byH.0. Jones and J. P. Millington.2 These workers were unable toresolve either phenylbenzylhydrazine, CH,Ph*NPh*NH,, by the aid ofd-camphorsulphonic acid, or methylaniline-p-sulphonic acid by crystal-lisation with cinchonine.H. 0. Jones 3 prepared phenylbenzylmethylethylammonium iodide,introducing the alkyl groups in three different orders, namely, bycombining benzyl, methyl, and ethyl iodides respectively with tertiarybase, but obtained no evidence bearing on the occurrence ofWedekind’s U- and p-isomerism. He resolved the quaternary iodideby Pope and Harvey’s m e t h ~ d , ~ applying the silver salt of d- andI n studying the following reaction,Ber., 1904, 37, 2702.Trans., 1904, 85, 223.a Proc. Camb.Phil. Soc., 1904, 12, 489.Ibbid., 1901, 79, 76,VOL. I. 146 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.I-camphorsulphonic acids in a water-free solvent. The sparinglysoluble salts are d-B d-A and I-B LA, and give EMID + 71.0' and - 7 1 - 2 O in aqueous solution. The basic ions therefore have [MI, + or- 19.5'. The optically active iodides give [a], + 8*3O and - 8.4' inalcoholic solution; they undergo autoracemisation in chloroform solution,much as do the d- and I-phenyl benzylmethylallylammonium iodides.Crystallographic measurements showed that the inactive iodide iseither pseudoracemic or a mechanical mixture. The correspondingI-bromide gives [ a ] D - 13.4O in alcoholic solution ; its rotatory powerdiminishes on recrystallisation from alcohol.Thomas and Jones havealso resolved phenylbenzylmethylisopropyl- and isoamyl-ammoniumiodides into their enantiomorphously related components.E. Wedekind and F. Oberheide2 have prepared the followingquaternary ammonium iodides containing asymmetric nitrogen atoms :p -tolylmethylethylallylammonium iodide, benzyl -y- tolylmethylallyl-ammonium iodide, benzyl-p-tolylethylallylainmoniuin iodide, andbenzyl-o-tolylmethylatllylammonium iodide, but have not resolved theminto optically active components.A. W. Harvey 3 has prepared phenyldimethylallylammonium iodidefrom dimethylaniline, but was unable to resolve the correspondingd-camphorsulphonate into fractions containing an optically active basicion.H. 0. Jones * has obtained two stereoisomeric phenylmethylallyl-Z-amylammonium iodides by the combination of methyl-Z-amylaniline withally1 iodide; one of the products is dextrorotatory and the otherlworotatory.I n chloroform solution, the rotatory powers of the saltsgradually change until a constant value is reached owing to dissociation,which causes optical inversion of the asymmetric nitrogen atom. Morerecently, BI. Scholtz has extended5 Jones's study of compounds con-taining both an asymmetric carbon and nitrogen atom. The combina-tion of n-ethylconiine with benzyl iodide leads to the formation of twoisomeric benzylethylconinium iodides of different melting points androtatory powers. Similar results were obtained on combining &so-amylconiine with benzyl iodide and n-benzylconiine with methyl iodide.Scholtz, however, has not observed any change of rotatory power ofthe isomerides such as is recorded by Jones.On treating dLdi hy dro-a-me t h ylindole with d-bromocam phor-sulphonic acid, W. J. Pope and G. Clarke obtained I-dihydro-a-methyl-indole d-bromocamphorsulphonate ([MID + 278' in water) as the leastsoluble salt ; the basic ion therefore has [MI, +5O, and on treatingthe salt with alkali, I-dihydro-a-methylindole was obtained. A second1 Proc. Canzb. Phil. SOC., 1904, 13, 33.3 TraYLs., 1904, 85, 412.Ber., 1904, 37, 3627.Bey., 1904, 37, 2712 and 3894.Trans., 1904, 85, 1330.4 Proc C a d . Phil. Xoc., 1904, 12, 466STE REOCHERIISTRY. 147salt of [hi], + 242.7" was isolated, but this does not give active basewith alkali despite the low value of the molecular rotatory power ; itis suggested that this salt really contains the active base, but thatduring the action of the alkali tautomeric change takes place in sucha way that the optical activity of the base is lost.Tattersall finds 1 tbat dZ-hydrindamine is conveniently resolved byfirst crystnllising it with d-tartaric acid, when d-hydrindamine hydrogen&tartrate is obtained pure, and crystallising the base recovered fromthe mother liquors with d-bromocxmphorsulphonic acid ; the latterprocess yields Z-hydrindamine d-bromocamphorsulphonate in ,z state ofpurity. On crystnllising d- and Z-hydrindamines with d-chlorocamphor-sulphonic acid, indications of the production of more than one saltfrom each base are obtained, just as when d-hrornocamphorsulphonicacid is used.2Last,ly, it should be noted that Kipping has prepared the asymmetricsilicon compound, phenylethylpropylsilicon chloride, PhEtPrSiC1, buthas not yet announced its resolution into components owing opticalactivity to the presence of an asymmetric silicon atom?w. J. POPE.* Trans., 1904, 85, 169.Proc., 1904, 20, 15.Kipping and Tattersall, ibid., 1903, 83: 918.L

ISSN:0365-6217    

DOI:10.1039/AR9040100132

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

ANALYTICAL CHEMISTRY.ALTHOUGH i t is no exaggeration to say that chemical analysis is thefoundation stone on which the greater part of the wonderful super-structure of modern chemist,ry has been reared, it is, and must for everremain, in a sense, the servant of the other branches of our Science.Restricted as it is to the solution of problems involving the identifica-tion and composition of various specimens of matter, we are necessarilyconcerned in a report such as this with improvements and developmentsof technique rather than with the elaboration of new theories, or thereview of great discoveries. For the sake of clearness it will be wellin reviewing the advances which have been made in this branch ofapplied chemistry during the past year if the matter is roughly classified,and I propose therefore to deal with the subject under the followingheadings :1.Inorganic analysis including electrochemical methods.2. Organic analysis.3. Analysis of foods and drugs.4. Apparat,us.It will, of course, be obvious that any such sub-division must be to i tcertain extent arbitrary, and in some cases it has been found difficultto decide under which heading a certain process should be grouped, butit is felt that the method adopted is that which is likely to be mostgenerally useful, and open perhaps to the fewest objections. Thepassing of the Food and Drugs Acts in this country and the existenceof similar adulteration acts in other States have created what isvirtually a special branch of analytical chemistry, having its ownobjects, and even its own methods, and it has therefore been thoughtbetter to deal with questions concerning the analysis of foods and drugsin a special section.I n .o r g u, n i c A n CG I? y s is.In the qualitative section of this branch of analysis there is com-Numerous papers have paratively little of importance to chronicleANALYTICAL CHEMISTRY:. 1‘49been published during recent years in which attention is called to thefact that a good many organic compounds may, with advantage, be pressedinto the service of both qualitative and quantitative inorganic analysis.I n the former case, the reactions usually consist of colour changes, andare open, very often in a marked degree, to the general objections whichcan so freqnently be urged against such indications.suggests the employment of tannin and of ether containing traces ofvinyl alcohol as tests for traces of vanadic acid, whilst Pozzi-Escot re-commendsthe useof theformer reagent as a delicate test for molybdenum.Diphenylca rbazide, again, which has previously been recommended byCuzeneuye as a sensitive reagent for mercury, copper, ferric iron, andchromic acid, and by Lecocq for molybdenum, is now recommended byMoulen 3 as a delicate test for traces of mercuric chloride in calomeland other mercurous preparations.Lacombe has suggested a newseparation of cerium from yttrium earths depending on the fractionalcrystallisation of the double manganese nitrates from nitric acid solu-tions, R process which is said to give better results than that ofPemarcay.Benedict 5 has proposed a simple method for the detectionof nickel in the presence of a large excess of cobalt, which would appearto be useful in some cases, Autenrieth indicates a useful microchemicalmethod for the detection of strontium in the presence of calcium andbarium, and Reichard 7 has studied the well-known nitroprusside reactionfor sulphides and has determined its limits of sensitiveness. Donau s hasdescribed an interesting microchemical method for detecting traces ofgold, dependiag on the red colour developed in silk threads previouslytreated with a rediicing agent. Instructions are given for obtainingthe solution of gold free from elements such as iron and arsenic, whichwould interfere, and it is stated that gold can be detected in a mineralmixture containing only one ten-millionth part by weight of thatmetal.The same author also finds that the colorations produced inborax beads by gold, platinum, and silver permit, under proper condi-tions, of the detection of exceedingly minute quantities of these metals.I n the domain of quantitative inorganic chemistry, some of the mostuseful papers, although those which often attract the least attention,are contributions dealing with investigations undertaken for the pur-pose of determining inore clearly the limits of accuracy of well-knownprocesses under the conditions obtaining in ordinary laboratory prac-tice, and of ascertaining to what extent the results are liable to beinfluenced by the presence, in varying proportions, of such acids orbases as are usually found in association with the element to be deter-Thus MatignonCompt.rend., 1904, 138, 82.L’Union Pharm., 1904, 46, 147.ti J. Amer. Chem. s’oc., 1904, 26, 695,7 Zeit. anal, Chem., 1904, 43, 222.Ibid., 200.Bdl. Soc. chim., 1904, 31, 570.Ber., 1904, 37, 3882.Monatsh., 1904, 25, 545 and 913150 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,mined. Work of this character is of the highest importance, foreven the most experienced analyst is apt at times to fail to realisehow far some of our common reactions may fall short of the ideallimiting cases, or to what extent associated substances may interfere.Thus, Hulett and Duschalk have confirmed the statement of Richardsand Parker, that when barium chloride is used as the precipitant thebarium sulphate obtained may contain an amount of chlorine equal to1 per cent.of its weight. Silberberger2 has, moreover, shown thatwhen barium sulphate is precipitated in the presence of ferric salts, asmall proportion of the iron is carried down as a double sulphate,whilst a little of the sulphuric acid remains in solution. The possiblecontamination of the barium sulphate with iron has, of course, beenwell known for a long time, but Silberberger further states thatnitrates as well as potassium may contaminate the precipitate to anappreciable extent. It should be pointed out, however, that Lunge3denies that basic ferric sulphates are formed in the analysis of pyrites,from which the sulphuric acid cannot be mashed out, and contends thatthe alcoholic strontium chloride method proposed by Silberberger isinaccurate when applied to the analysis of that mineral.Knight,4S t ~ l b e r g , ~ and Hillebrand all assert that a single precipitation does notsuffice to effect the complete separation of calcium from magnesium,but that a second is essential if the greatest possible accuracy is aimedat ; Blount,G on the other hand, has shown that under proper conditionsone operation, in the case of cement analysis, at least, is capable of yield-ing results in which any error is so slight as to be quite negligible.Persulphates are now finding somewhat extensive employment asoxidising agents in analytical operations, and during the past yearone or two new uses for these salts have been suggested.Thus,Imbert and Dumolard 7 have shown that the ammonium salt furnishesa convenient means of estimating bromide in the presence of chloride,the former being decomposed into bromine and bromate, whilst thelatter remains unattacked. G. v. KnorrejS again, has shown thatwhilst it is impossible to effect a sharp separation of manganese fromcopper, zinc, cadmium, nickel, and magnesium by means of ammoniumpersulphate, that substance permits of a very accurate separation ofmanganese and chromium, the former being precipitated as the peroxideand the latter converted into chromic acid. This method has beenapplied with good results to the estimation of manganese in iron byIkdert .gZeit.anorg. Chenz., 1904, 38, 196.Zeit. anyew. Chem., 1904, 17, 949.Zeit. anyew. Chern., 1904, 17, 741 and 769.J. SOC. CJzewi. ImE., 1904, 23, 1218.Afonatuh., 1904, 25, 220.Cfmn. News, 1904, 89, 146.7 Ann. Chim anal., 1904, 9, 21.9 2e.i.t. anyew. C h e w , 1904,17,422. 8 Zeit. anal. Chenz., 1904, 43, 1AN A LYTICAL CHEhIISTR1'. 151I n connection with the above work of v. Knorre, Dittricli andHassell have more recently shown that the separation of manganesefrom the above-mentioned metals cau be completely effected if asecond precipitation is resorted to, and that even a single operationsuffices when they are present in comparatively small quantities.Friend 2 has called attention to the fact that hydrogen peroxide can onlybe accurately estimated by permanganate in the presence of per-sulphates under certain well-defined conditions, which are not thoseordinarily observed, As instances of useful revision work, attentionmay be called 60 the extensive investigation by Daniel of the Wohler-Fresenius method for the estimation of fluorine, and to the paper byWaring on the volumetric ferrocyanide method of estimating zinc.Tn the first case, the author confirms the accuracy of the process, andindicates fully the precautions which have to be taken in order to obtainthe best results, whilst in the second attention is directed t o severalimportant sources of error.Gutbier, Metzner, and Lohmann havemade a comparative study of the various gravimetric methods for theestimation of selenium, and have found the majority more or lessunsatisfactory, although good results can be obtained by employinghydrazine salts as the reducing agents.For ths estimation of uraniumin uranyl compounds, Glasmann 6 has proposed an iodometric methodwhich gives good results and appears susceptible of useful application.Lunge has very carefully compared the permanganate and sulphanilicacid methods for estimating nitrite, and has come to the conclusionthat whilst there is very little difference between them in point ofaccuracy, the far greater simplicity and convenience of the perman-ganate process marks it out for general adoption. The same authorhas published a series of papers 8 dealing with Inclicatom, iodometry,and the se Zection of standurd substances fov alkalimetric titrations,in which a number of points of interest and importance to analystsare dealt with.I n connection with iodometry, it may be mentionedthat Young states that he has used anhydrous sodium thiosulphatefor the standardisation of iodine solutions with excellent results.RaschiglO prepares for the same purpose a standard solution of sulphurdioxide by passing the gas into water, weighing, and then diluting toa known volume. He also recommends a similar method for preparingstandard solutions of hydrogen chloride, but the principle is not byany means new, having been suggested some years ago by Moody.'lZeit. anal. Chem., 1904, 43, 382.Zeit. morg. Chenz., 1904, 38, 257.Zeit. anorg. Chem., 1904, 38, 291.Chem. Zeit., 1904, 28, 501.J.Anter. Chenz. SOC., 1904, 26, 1028.Trans., 1904, 85, 597.J. Amer. Chem. Soc., 1904, 26, 4.Ber., 1904, 37, 189.* Zeit. angew. Chem., 1904, 17, 195, 225, and 265.l1 l'rans., 1898, 73, 658.lo Zeit. nngezo. Chm., 1904, 17, 577152 ANNTJAL REPORTS ON THE PROGRESS OF CHEMISTRY.Titanium in the tervalent condition, which has already been recom-mended by Knecht as a reducing agent in organic analysis, is foundby Stahlerl to constitute a convenient reagent for the volumetricestimation of hydroxylamine. The results are accurate, and the methodwould appear to be capable of extended employment. Attention mayhere be directed to an interesting paper by McCoy2 dealing with theionisation constants of phenolphthalein in relation to the employmentof that substance as an indicator, and also to one by Greeu andPerkin3 on another aspect of the same subject'.Iluring recent years, many organic substances have been suggestedfor use in quantitative estimations and separations, some of whichappear to be capable of useful employment.One of the first, and onewhich is susceptible of somewhat wide application, is nitroso-P-naphthol;this substance has now been found by G. v. Knorre* to be capable ofeffecting the complete separation of iron from zirconium.finds that thorium can be quantitatively separated in two precipita-tions from cerium, lanthanum, and didymium by m-nitrobenzoic acid,and that the process gives good results in the analysis, for example,of monazite sands.In this connection, it is interesting to note thatErdmann and Makowka6 have found that palladium can be readilyseparated by means of acetylene from platinum, iridium, rhodium,gold, and copper. Hydrazine is another reagent which has of lacefound somewhat extensive application in analytical operations, andJannasch and Bettges 7 have recently shown that by its aid mercurycan be separated from molybdenum and tungsten, and that palladiumsand platinum in the presence of ammonia9 may be separated frommany other metals and estimated. Schlotter 10 has also found thatiodates and chlorates are, like bromates, reduced by hydrazinesulphate to the corresponding halides. Plimmer 11 has shown thatsilver cyanide may be separated from the chloride by boiling withdilute nitric acid, and that the drastic treatment originally recom-mended for this purpose by Kraut is not necessary.An apparentlyuseful process for the estimation of iodide, bromide, and chloride,when present together, has been devised by Thilo,12 depending on theorder in which the silver halides are formed on the addition of silvernitrate. A number of processes capable of giving fair results andinvolving the use of hydrazine salts have, during recent years, beenAwzcr. Chem. J., 1904, 31, 503.Zeit. nngew. Chena., 1904, 17, 641 a i d 676,NeishBer., 1904, 37, 4732.Trcms., 1904, 85, 398.J. Amer. Chern. Soc., 1904, 26, 780.Ber., 1904, 37, 2694.Jannaseh and Bostosky, Ber., 1904, 37, 2441.Jannnsch and Stephan, zbid., 1980.lo Zeit.anory. Chem., 1904, 38, 184.l1 ?'ra'~~s., 1904, 85, 12.' Ibid., 2210, 2219.l2 Chcm. Zei 1904, 28, 866ANALYTICAL CHEMISTRY. 153suggested for the gasometric estimation of certain metals, and Girardand Saporta 1 have recently further inGestigated the method as appliedto the estimation of copper and nitrites.bas directed attention to the use of palladium-hydrogen as a reducingagent in quantitative analysis, and has pointed out that this substancemay be used with great advantage in the converbion of ferric intoferrous salts, chromates into chromic salts, ferricyanides into fen o-cyanides, and ceric into cerous salts, inasmuch as complete reductionis in all these cases readily effected, and the resulting solution is ofcourse not contaminated with any products derived from the reducingagent.He has also found that '' uncharged ') palladium dissolvesreadily in acid solutions of ferric and cupric chlorides, palladiouschloride being formed together with the lower chlorides of each of theabove metals. I n a number of other cases which have been studied,reduction either does not occur at all or is very incomplete.has recorded some experiments on the separation and estimation ofarsenic by distillation in hydrogen chloride and hydrogen sulphide, amethod which was some years ago proposed by Piloty and Stock forthe separation of arsenic and antimony. This paper, which deals withthe se aration of arsenic in its two states of oxidation, may be usefullyconsulted by all who have to estimate that element in minerals andother natural products.The direct estimation of boron in minerals was for long so difficulta matter, and the results obtained were so uncertain, that this elementwas usually determined by difference.Schaak4 has now applied thewell-known methods of Thomson and of Gooch to naturally-occurringborates, and finds that good results can be obtained.I n electrochemistry, as applied to analytical separations and esti-mations, much progress has been made during the year, the work ofHollard and his colleagues being of special importance. Theimpossibility of effecting the separation of metals the electrolyticpotentials of which are higher than that of hydrogen is well known,the difficulty being, of course, due to the liberation of hydrogen atthe cathode, and to the virtually increased resistance of the cell.Freudenberg was one of the first to recognise and study the bearing ofvariations of tension in electrolytic separations, and much work onthis subject has since been done.Hollard has now shown that thedifficulties above referred to in connection with the high po1:iyirationpotentials of certain metals may be largely overcome by constructingthe anode of a soluble metal or by surrounding it with a reducingsolution, and in this way it has been found practicable to separate, forexample, zinc from nickel. I n addition to this, he has made manyBd1. ,Sot. chim., 1904, 31, 905.Trans., 1001) 85, 1001.The author of this reportMorganAitalyst, 1904, 29, 346,J.SOC. Chem. I d . , 1904, 23, 699154 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.experiments in the direction of constructing the cathode of othermetals than platinum with very useful results. The principle ofseparation by the use of complex salts is dealt with in a paper byHollard and Bertiaux,l who show that nickel may be separated fromzinc and zinc from iron by converting the zinc into zinc ammoniumnitrite and the iron into potassium ferrocyanide. This method is,however, to some extent limited in its application by the fact thatcertain complex ions (for example, the double cyanides of gold, silver,cadmium, and mercury with potassium) themselves appear to dis-sociate, and so permit the deposition of the heavy metal on thecathode. I n extension of the recently published work of Edgar F.Smith,2 Meyers has made further experiments with mercury cathodes,and has found that chromium can be accurately estimated in sulphuricacid solutions, and has been successful in effecting a number of im-portant separations.Other papers have been published by Perkiriand Prebble, Richards, Gallo, Amberg and others dealing withimproved forms of electrodes or cells, and with the improvement ofexisting processes. The adoption of a rotating anode together withthe employment of comparatively high pressure currents have enabledIngham4 to effect successfully the estimation of zinc, and in the handsof Ashbrook similar conditions have given good results in the quanti-tative separation of a number of metals which have not hithertoproved amenable to electrolytic treatment. Hollard and Bertiaux 6discuss the electrolytic separation of bismuth and copper, and describea useful method for estimating very small quantities of the formermetal in the presence of large amounts of lead.As another exampleof the application of the methods above referred to, attention may becalled to the electrolytic separation by Coehn and Kettembeil7 of thealkali-earth metals. A recent paper by Hollard* may be usefullyconsulted by all who employ the electrolytic method for the estimationof lead. I n this i t is shown that the composition of the ‘(peroxide )’deposited on the anode, and consequently the analytical factor to beused, depends not only on the concentration of the electrolyte, butalso on the physical character of the electrode.A paper by the sameauthor and Bertiauxg dealing with the assay of alloys of platinum,gold, and silver is virtually a criticism of the methods of assayingin vogue in France, and may be uaeEully referred to by all interestedin this branch of analysis.The attention of water analysts is directed to an interesting seriesBull. SOC. chim., 1904, 31, 900. ‘d J. Ayner. Chem. Soc., 1903, 25, 883.3 Ibid., 1904, 26, 1124.5 Ibid., 1283.7 ,%it. anorg. Chem., 1904, 38, 198.9 Ann. Chiirz. anal., 1904, 9, 287.Ibid., 1269.Bull. SOC. chim., 1904, 31, 1131.Compt. rend., 1904, 138, 142ANALYTICAL CHEMISTRY. 155of analyses of waters from the oolite-formations by Fisher,l which goto show that whenever these are covered by clay, alkaline supplies areobtained, whilst hard calcareous water is invariably got from theuncovered beds.Two papers dealing with the solubility of salts have appeared duringthe year, the one by Kohlritusch,Z who has calculated from theelectric conductivity of saturated solutions the solubility in water ofa number of sparingly soluble salts, the other by N a ~ m a n n , ~ who givesthe solubility of a very large number of metallic derivatives in acetoneand pyridine solutions.Comparatively little advance has been made in connection with theanalysis of gases, but Woh14 calls attention to the very appreciableerror which may sometimes be introduced into the results of gasanalysis, made by combustion methods, by assuming that the molecularvolumes of all gases are the same, and urges that the true molecularvolumes according to the latest det,erminations should in all cases betaken.Richardt has studied the fractional combustion of gasescontaining hydrogen when mixed with air and passed over heatedpalladium wire, and Pfeiffer 6 has proposed an improved method forthe estimation of benzene in coal gas, in which the dinitrobenzeneobtained is estimated volumetrically.All who are interested in technical calorimetry, with more especialreference to the examination of coal, will read with considerable inter-est a paper by Gray and Robertson,' in which several different typesof calorimeter are compared and their indications discussed.Orynnic Ancc1ysis.Fur the rapid and simultaneous detection of the halogens, phos-phorus, arsenic, and sulphur in organic compounds, Pringsheim hasrecommended a useful and simple method in which sodium peroxide isemployed as the oxidising agent.Kling and Ward9 have shown that the different behaviour ofprimary, secondary, afid tertiary fatty alcohols, when heated, affordsa method of differentiating between them, which may in some cases beusefully employed either in place of, or in addition to, the existingwell-known methods.A number of reactions have been described byvarious authors for the detection and identification of certain organiccompounds, but these, whilst in many cases useful, are scarcely ofAnalyst, 1904, 29, 29.b'er., 1904, 37, 4328 and 4609.Joum.Gusbelez6cht, 1904, 47, 566 and 590.Chem. Zeit., 1904, 28, 884.2 Zeit. physikd. CJmz., 1904, 50, 355.Ibid., 429.7 J. SOC. Chew. h i d . , 1904, 23, 704,9 Bull. Soc. chinz. 1904, 31, 783. 8 Ber., 1904, 37, 2155156 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.sufficient general interest or importance to merit special reference.An exception may perhaps be made in favour of the method proposedby Freundler for the identification and approximate estimation ofmethyl anthranilate, since this should be cepcalvIe of somewhat wideapplication.Collie has described a method for the estimation of carbon andhydrogen in certain organic compounds, based upon that first suggestedby Saussure and Prout, in which the weighed substance is burned ina measured volume of oxygen.It is pointed out that in the case ofthose compounds to which it can be applied the method has the meritsof accuracy and rapidity of execution, whilst the very small amountof substance required constitutes a still further advantage,recommends the use of phosphoric acid, on account of its non-volatility,for the decomposition of carbonates in the direct estimation of carbondioxide, and states that organic carbon, when present, may be deter-mined in the residue by the chromic acid method with good results.Combustion with sodium peroxide has been employed by Pringsheimfor the estimation of halogens, phosphorus, and arsenic in organiccompounds with excellent results, and von Konek has also recom-mended the use of this oxidising agent, although under somewhatdifferent experimental conditions.The last-named author points outthat whilst a similar process may be employed in some cases for theestimation of nitrogen, a number of compounds, f o r example, pyridineand quinoline, do not yield the whole of their nitrogen as nitrate. I nmany instances, it is clear that peroxide “combustion” may beadvantageously employed in ultimate organic analysis, but, on theother hand, a perusal of some of the published papers produces theimpression that the method has been recommended for estimationswhich can be far more easily and accurately carried out by the ordi-nary well-known methods. Attention may also be called t o thechromic acid oxidation process for the estimation of halogens in organiccompounds proposed by Baubigny and Chavanne,G which is stated togive very accurate results.Kjeldahl’s method for estimating nitrogen continues, as is natural, toattract the attention of investigators, and modifications (many of whichdo not constitute improvements) are from time to time suggested.R.B. Gibson has shown that, contrary to the statement of Kutscherand Steudel, the nitrogen in creatine, uric acid, hippuric acid, andsome similar compounds can be accurately estimated by this process,MorganBull. Soc. chim., 1904, 31, 882.Ibid., 1004.Bull. SOC. chim., 1904, 31, 396.Trans., 1904, 85, 1111.Anter. Chem. J., 1904, 31, 386.5 Zeit. wngtzv. Chem., 1904, 17, 886, 888, and 1093.7 J. Amer. Chem. h’oc., 1904, 26, 105ANALPTICAL CHEMISTRY.157whilst Sherman and Falk 1 are of opinion that the Gunning-Kjeldahlmethod, when carried out as suggested by Dyer,2 combines all theadvantages of the other modifications of this method. I n this paper,attention is called to the fact t h a t it is in many cases necessary t ocontinue the sulphuric acid digestion for some time after the liquidhas become colourless. It is well known that the use of glass for thepurpose of condensing the ammoniacal steam may introduce a n appreci-able error into the determination, and Schiinewald and Bartelt 3 haveexamined the behaviour of different kinds of glass in this respect.Debordeaux4 has devised a method based on distillation withpotassium thiosulphate and potassium snlphide for the determination ofnitrogen, which is applicable t o a large number of organic compoundsdiffering widely in character, and which is said to yield pure ammoniawithout any admixture of amines such as sometimes occurs with otherprocesses.Hibbert and Sudborough 5 have investigated the magnesium alky 1haloid method proposed by Tschugaeff for the detection of hydroxylgroups, and have found that with proper precautions good quantitativeresults can he obtained.A. G. Perkin6 has described a method forthe determination of acetyl groups, which is simple and yields goodresults.Stritar and Zeidler 7 recommend for the determination of methylalcohol a slight modification of the method devised by Zeisel and Fantofor the estimation of glycerol. I n this, the alcohol is converted intomethyl iodide and weighed as silver iodide.The process is recom-mended for the estimation of methyl alcohol in commercial form-aldehyde, in wood spirit, and in crude pyroligneous acid. While refer-ring to the above-mentioned method for glycerol estimation, it may bepointed out that, following on the adverse criticism of Lewkowitsch,Fsnto S has been led t o modify the original conditions, having found,after further investigation, that correct results cannot be obtained inthe estimation of glycerol in fats by treating the fat directly with thehydriodic acid. I n connection with the analysis and evaluation ofessential oils, much work has been done, a n ever-increasing body ofinvestigatoi-s being attracted to this comparatively new field of research.The majority of the published papers deal either with the investigationof new products or with the detection of adulterants in the moreexpensive oils of commerce, and, even if they were of sufficient generalinterest, are so numerous that it is impossible to refer to more than aJ.Aivzer. Chem. SOC., 1904, 26, 1169.Woch. Rmu., 1904, 21, 793.T7-ans., 1904, 85, 933.Trans., 1895, 67, 811.Compt. rend., 1904, 138, 905.PTOC., 1904, 20, 171.7 Zeit. anal. Chcm., 1904, 43, 387, 401.8 Zed. angeto. Chem., 1904, 17, 420158 ANNUBL REPORTS ON THE PROGRESS OF CHEMISTRY.few of them in this report. Burgess1 has shown that the methodpreviously suggested by him for the estimationof citral in oil of lemonis applicable to the estimation of aldehydes and ketones in a numberof other essential oils.This method, which depends on the factobserved by Tiemann that when a neutral siilphite in solution is addedto an aromatic or fatty aldehyde an additive compound is formed withthe simultaneous production of sodium hydroxido, which can, of course,be titrated, has also been investigated by Sadtler,2 who arrives at thesame conclusion as Burgess. The method of est irnating cinnamaldehydeas semi-oxamazone recently proposed by Hanus has been examined inSchimmel’s laboratory, and is stated to be of considerable ~ t i l i t y . ~ Themethod proposed by Ramber for the examination of citronella oil 4 hasnow been adopted as official by the Ceylon Government, but has beenadversely criticised by SchirnmeL5 Rose oil has been usefully studiedfrom the analytical point of view by Jeancard and Satie,G and also byHudson-Cox and W.H. Simmons.7 The last-named author S has con-tinued his work on the iodine absorption of attar of rose, and hasobtained results which confirm his opinion as to the value of this testin judging the purity of this oil, but the refractive index is found tobe of very little value for this purpose. The sodamide method sug-gested by Schryver for the determination of phenols in essential oilshas been further examined in Schimmel’s laboratory, and has beenfound inapplicable in the presence of alcohols. As Schryver has alreadyshown that aldehyde and ketones also interfere, it is clear that itsemployment must be restricted to oils consisting solely of hydrocarbonsand phenols, in which cases it gives very satisfactory results.Theincreasing and more refined adulteration of turpentine has led manychemists during the past few years to devise and study new methodsfor its detection, and papers by Worstall,9 Harvey,lO and McCandless l1are useful contributions to t h i s subject. Some attention has beendevoted during the past year to the study of the colour reactions ofcertain fixed oils with the object of ascertaining to what extent theymight be relied on as evidence of sophistication, and, speakinggenerally, it may be said that the results have shown them to be lesstrustworthy than is often assumed. Some of these will be referred toin the section dealing with the analysis of foods and drugs.Severalinvestigators have devoted attention to the comparison and extendedstudy of the better known iodine absorption processes, among the moreAnalyst, 1904, 29, 78.Beport, 1904, October/November.Annlyst, 1904, 29, 175.J. SOC. Chem. Ind., 1904, 23, 302.l1 J. Arner. Chem. SOC., 1904, 26, 981.J. SOC. Chem. Ind., 1904, 23, 303.Proc., 1903, 19, 292.Bull. ~Yoc. China., 1904, 31, 931.3 Schim?nel’s Beport, 1904, AprilIMay.8 C?xmist n7zd Dmggist, 1904, 65, 703.lo Ibid., 413ANALYTICAL CHEMISTRY. 159important papers being one by Archbutt,l who has compared theiodine-bromide method with that of Wijs in favour of the latter, andone by Tolman,2 in which the methods of Hubl, Wijs, Hanus, andMcIlhiney are reported on. From the more purely scientific point ofview, a paper by Ingle 3 on the iodine value of unsaturated organiccompounds will be found to be of considerable interest.The methodrecently proposed by Partheil and Ferie for the separation and esti-mation of saturated fakty acids? and which was based upon differencesin the solubilities of their lithium salts, has been examined by Fahrionand by Farnsteiner,5 both of whom report it to be untrustworthy.LewkowitschG has proposed the hexabromide test as a means ofdifferentiating between linseed and '' boiled " oils, and has describedthe analytical reactions of some almond and allied oils. The detectionof the adulteration of beeswax has been usefully dealt with by Cohnq7I n connection with the chemistry of the sugars, Ofner has studiedthe phenylmethyl- and phenylbenzyl-hydrazine derivatives of thealdoses, and is of opinion that these compounds may be iisefnllyemployed in analytical operations, whilst Neuberg confirms his pre-vious statement that phenylmethylhydrazine is capable of beingsuccessfully used for the detection of kevulose in the presence ofdextrose, and for its identification in carbohydrate mixtures.Descriptions of new processes for the estimation of the sugars, manyof which are characterised by considerable ingenuity, are constantlybeing published, but, apart from some special application, they do notconstitute any improvement on the gravimetric Fehling method, whichis now, in one form or another, almost universally adopted.ThusRosenthaler l o proposes to titrate the acids formed by the oxidation ofthe reducing sugars by Fehling's solution, whilst Oerum l1 suggests thesolution and colorimetric estimation of the reduced cixprous oxide.I n an interesting paper,l2 Noyes, Crawford, Jumper, Flory, andArnold describe experiments made on the rate and extent of thehydrolysis of maltose and dextrin as effected by dilute acids, and givea method for the estiniation of starch which properly includes apreliminary hydrolysis of that substance by diastase. It is strangethat,, in spite of all the work done during recent years, so many authorsshould still recommend direct acid inversion methods for starch estima-tion, and burden chemical literature with the more or less inaccurateresults obtained.That the optical rotations of certain of the sugarsJ. Soc. Chem. Ind., 1904, 23, 306.J. SOC. Chem. Id., 1904, 23, 422.Zeit. Ncthr. Qenussnz., 1904, 8, 129. ' Zeit. oflent?. Chem., 1904, 10, 404 and 415.Ber., 1904, 37, 3362 and 4399.lo Zeit. anal. Chem., 1904, 43, 282.l2 J. Amer. Chem Xoc., 1904, 26, 266.J. Amer. Chem. Soc., 1904, 26, 826.Zeit. angew. Chem., 1904, 17, 1482.Analyst, 1904, 29, 2.Ibid., 4618.l1 Ibid., 356160 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.are not the same in acid as in neutral solution, and cannot thereforebe regarded as constant numbers, is sometimes overlooked by sugarchemists, and Remy usefully calls attention to the error which maybe introduced into the estimation of cane sugar by Clerget’s methodwhen lzvulose is present in the original substance by the failure torecognise this fact. Ling and Rendle2 have pointed out that con-centrated malt extract invariably contains large proportions of dextroseformed naturally from the starch during manufacture, which is ofimportance, inasmuch as these extracts now find considerable employ-ment in commerce, and.the presence of dextrose might otherwise havebeen thought to indicate adulteration with glucose.Reference mayhere be made to a paper by Ford in which he describes the preciseconditions which must be observed in the determination of the pre-existent sugars in grain by extraction with alcohol. No analyst whois accustomed t o make determinations of the diastatic activity of maltwill need to be reminded that this arbitrary number is largelyinfluenced by the precise temperature and time conditions adoptedduring extraction and digestion, but it is not as clearly recognised thatother, and apparently trivial, details may affect the result to anappreciable extent, and an exhaustive paper by Ford * dealing withthe subject will well repay careful study.The number of new colour reactions to be obtained with variousalkaloids seems to be limited only by the number of observers and bythe patience and ingenuity they exhibit, and whilst some of these maybe serviceable, many are obviously of very little value in ordinaryanalytical practice.Reichard points outl that cocaine yields asparingly soluble nitroprusside which may a t times be useful ineffecting its separation from morphine, and gives some new colourreactions of the former alkaloid. New colour reactions of morphine arealso given by Ballandier 6 and by Rosenthaler and Turk,7 of pilocarpineby Barral,* and of strychnine and brucine by R e i ~ h a r d .~ LQger lo hasexamined the well-known And& (Thalleioquin) reaction for quininewith the object of ascertaining the conditions of greatest sensitiveness.Schidrowitz 11 has compared several processes for the estimation ofmorphine in opium, and has described a method which is, in his opinion,superior to others both in simplicity and accuracy, and which is basedto some extent on the Pharmacopoeia Germanics IV process. Forthe estimation of codeine in the same drug, Caspari l2 describes a processBull.Assoc. Chim. XUCT. Dist., 1904, 21, 1002.Analyst, 1904, 2 9 , 243.J. Soc. Chem. Ind., 1904, 2 3 , 414.J. Pharm. Chim., 1904, 19, 151.J. Phn,r?n. Chim., 1904, 19, 188.3 Ibid., 277.Chem Zeit., 1904, 2 8 , 299.Apoth. Zcit., 1904, 19, 186.Chcm. &it., 1904, 28, 977.lo J. Pharm. Chim., 1904, 19, 281 and 434.la Pharm. Eev., 1904,222, 348.l1 Analyst, 1904, 2 9 , 144ANALYTlCAL CHEMISTRY. 161which is stated to give good results and to be superior to that of Van derWielen. StanGk points out that betaine can, under certain conditions,be quantitatively precipitated by a solution of iodine in potassiumiodide, and may thus be separated from glycine, asparagine, tyrosine,and other substances with which it is often associated.This methodwhen fully worked out would appear to be capable of usefulapplication.have shown that Keller’s process for the assayof digitalis tinctures gives results far below the truth, and they are ofopinion that at present the physiological method is the only reliableone. Several papers dealing with the estimation of tannin and theanalysis of tanning materials have been published during the year.Perhaps the most important of these is one by Parker and Payne3describing a process which is said to be in many respects superior tothe well-known hide-powder process. This method has, however, beencriticised by Dreaper,4 who recommends for the estimation of tannicand gallic acids a modification of a process which he first describedsome years ago, and has also been referred to by Wood and Trotman,Gwho have made an examination of the so-called “ collin ” which Parkerand Payne use for the precipitation of tannin.The hide-powderprocess in the form recommended by the Association of AmericanOfficial Agricultural Chemists is dealt with by Mardick,6 who proposescertain modifications of procedure. H, Wislicenus also devotesattention to this subject, and recommends the use of a highly porousaluminous material in place of hrde-powder, which is said to giveresults a t least equally good, and to constitute a far more convenientreagent.Barger and ShawAIialysis of Food und B~zcgs.Owing to its great importance, and to the fact that it was not inthe hands of the public until the beginning of 1904, the Report of theRoyal Commission on Arsenical Poisoning in Food may be fittinglyreferred to here, notwithstanding that it was signed in November1903.Of chief importance from the point of view of analyticalchemistry is the recognition by the Commissioners of the fact thatsatisfactory estimations of arsenic in food-stuff s and other materialscan be made by the comparison of mirrors obtained by the employmentof the Marsh-Berzelius method. This process, which had previously beensuggested for the purpose by the Joint Committee appointed by theSocieties of Chemical Industry and Public Analysts, has now been1 Zeit. Zuckerind. Bohnz., 1904, 28, 578.3 J. SOC. Chem. Ind., 1904, 23, 648.5 J.Xoc. Chem. Ind., 1904, 23, 1071.7 Zeit. angew. Chem., 1904, 17, 801.Pharm. J., 1904, 18, 249.Chcnt. ATews, 1904, 90, 111.B i d . , 1187.VOL. I. 162 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.most rigorously tested, and in one form or another is almost universallyemployed in this country. The Commissioners remark that they donot attempt to pronounce for or against any particular modification ofthe Marsh-Berzelius method, and that they are satisfied that carefulanalysts will be able to obtain results sufficiently exact and comparablefor practical purposes, even although the details of their proceduremay differ. At the same time, they refer to the electrolytic processrecommended by the Board of Inland Revenue Committee,l andindicate gome of the advantages which it appears to possess over thezinc method.Owing to the wise decision of the Commission not torecommend any special form of apparatus or procedure as official orstandard, and to the great difficulty of obtaining zinc of a sufficientlyhigh degree of purity and sensitiveness, much attention has beendevoted to the improvement of the electrolytic process. The InlandRevenue Committee method, above referred to, whilst excellent inmany respects, suffers from the disadvantage of being less sensitivethan the zinc process, and of necessitating the previous reduction ofarsenates. The latter difficulty appears to have been first avoided byTrotman by the addition of zinc sulphate to the contents of thecathode compartment, and since then several investigators have experi-mented with cathodes constructed of other metais than platinum.Thus, Sand and Hackford recommend lead for this purpose and describen form of apparatus which is said to be highly sensitive, inasmuch asit will detect 0.0000005 gram of arsenic in 59 C.C.of liquid, and alsovery convenient. Arsenates are readily reduced, and it is stated thatcommercial lead ‘‘ absolutely free from arsenic and antimony ” can beobtained. It is to be noted, however, that W. Th~mson,~ who hasalso tried lead cathodes, speaks of the arsenic which it contains ascoming off “gradually for a long time,” and describes the resultsobtained as ‘‘ irregular.” H e also recommb nds a special form ofapparatus with a pure zinc cathode, and claims that the indications aremuch more sensitive than those given by the Committee’s method.A report dealing with the detection of arsenic in the drugs of theBritish Pharmacopceia has been presented to the Pharmacopceia Com-mittee of the General Medical Council by Dunstan and Robinson.The authors recommend a modification of the test first proposed byMayenSon and Bergeret on the ground that it is capable of easyapplication and avoids the working difficulties involved in the use of theMarsh-Berzelius method.I n all other respects, however, the suggestedtest is decidedly inferior. I n this connection it may be noted thatCloud 4 has employed the Marsh-Berzelius method for the estimation ofTmiis., 1903, 83, 974.Mem. Proc. ilfanchester Phil.Soc., 1904, 48, 1.J. Soc. Chew,. hid., 1904, 23, 524.I! lbid.? 1904, 85, 1018ANALYTICAL CHEMISTRY. 163minute quantities of arsenic in copper ores and metallurgicalproducts. Another important Official Report (Final) recently issuedis that of the Departmental Committee on Butter Regulations. Inthis there is little or no direct reference to analytical procedure, butthe majority of the members recommend the adoption of twenty-fouras the limiting Reichert-Wollny number, below which a presumptionshould be raised that butter is not genuine. The recent extensive useof cocoa-nut oil in the manufacture of margarine and in the adultera-tion of butter has done much to diminish the value of the indicationsof the Reichert-Meissl and Reichert-Wollny methods.The process,for instance, which was made official in 1900 for the estimation ofbutter-fat in margarine, and which was devised by the principalchemist of the Government Laboratory in collaboration with a Com-mittee of the Society of Public Analysts, is no longer to be implicitlyrelied on, and will doubtless have to be modified. Polenskel de-scribes a method for the determination of cocoa-nut oil in butter,This involves an estimation of the volatile insoluble in addition to thevolatile soluble fatty acids distilling over in the ordinary Reichert-Meissl process (“new butter number”), and is based on the well-known fact that the proportion of the soluble to the insoluble volatilefatty acids is far higher in butter than in cocoa-nut oil.Muntz andCoudon2 have worked out a method very similar to that of Polenskeand have independently arrived at practically the same conclusion.The correctness of the principles underlying these methods does notadmit of doubt, and they cannot fail to be of very great assistance inthe solution of a difficult and important problem. Juckenack andPasternack3 also deal with this subject, and point out that whilst theordinary constants obtained in butter analysis do not suffice to showthe presence of cocoa-nut oil, a consideration of the relation existingbetween certain of these, coupled with a knowledge of the molecularweights of the soluble and insoluble fatty acids, suffices, in manycases, to lead t o a definite conclusion. Siegfeld4 has made furtherexperiments with the phytosterol acetate test, and states that he hasconfirmed the accuracy of his previous statements that 10 per cent.ofcocoa-nut or other vegetable oil can be detected in butter by itsaid. Hoton 5 describes an apparently useful method for the analysisof butter based on the fractional separation of the glycerides from anacetic acid solution by cooling, and the determination of the refractiveindices and Valenta numbers of the separated fractions. In connec-tion with this subject, an important paper on u The Interdependence ofZeit. Nahr. Genussm., 1904, 7, 273.2 Annnles de l’lnstitut national ng~onomique, 2” sthie, Tome 111, Fsscicule Ier.Zeit. Nahr. Qenzcssm., 1904, 7, 193.5 Bull. Soc. Chim. Belg., 1904, 18, 147.Bid., 577.M 164 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the Physical and Chemical Criteria in the Analysis of Butter-fat " hasbeen published by T. E.Thorpe,l and will be studied by all who areinterested in this branch of analytical chemistry. Several investiga-tions have been undertaken in connection with the estimation of fatin milk, and one o r two new modifications of well-known methodshave been proposed, but they are scarcely of sufficient. interest orimportance to merit special reference. Richmond 2 gives the averagecomposition of more than 15,000 samples of milk analysed during1903, the average fat percentage having been 3.83 per cent. Sjollemaand Visser independently 3 describe experiments made for the purposeof deciding which is the most accurate process for the estimation of fatin cheese, and arrive at the conclusion that the methods of Bondzynskiand Gerber are the best, and that ether extraction gives low results.Harrison: in a paper on the analysis of condensed milk, gives theresults of a number of experiments made for the purpose of ascertain-ing the best conditions for the estimation of cane sugar and lactose,and Richardson and JaE6,5 dealing with the same subject, propose apolarimetric mpthod involving readings a t 20" and at 8 6 O , the invertsugar producing, as is well known, no rotation at the higher tempera-ture.The present high price of cod-liver oil and the consequenttemptation to adulterate with vegetable or cheaper fish oils has causedthe question of its analytical examination to assume considerableimportance.Liverseege 6 publishes the results of an investigation ofa number of genuine samples as well as of several allied liver and fishoils. From these, as well as from the results of other workers, it wouldappear that the detection of sophistication is often a makter of verygreat difficulty, but that the refractive index as determined by thebutyro-refractometer of Zeiss and the Valenta test are amongthe most useful. The sulphuric and nitric acid colour reactionis also very good, and i t is pointed out incidentally that the testsspecified in the British Pharmacopaeia are of very little value for thepurpose of discriminating between the genuine and the adulteratedoil.During recent years, much attention has been devoted to the study ofthe nucleins and the derived purine bases in their relation not only tonormal metabolic changes in the animal organism, but also to certainpathological conditions.Much excellent work has been done, and theincreasing importance of the subject to the food chemist is becomingclearly recognised. Methods for the recognition and approximate separa-tion of the purine bases have been known for some time, and have beenapplied by different observers to the examination of various foods.Trans., 1904, 85, 248.Hoorn. Chemisch. Week. Vlad., 1904, 29,J. Soc. Chent, Ind., 1904, 23, 309.Analyst, 1904, 29, 180.Analyst, 1904, 29, 248.Analyst, 1904, 29, 210ANALYTICAL CHEMISTRY. 165During the past year, Micko 1 has published the results of the continua-tion of his detailed analytical examination of samples of meat and yeastextract, and has described the methods he has adopted for the identifica-tion of the so-called xanthine bases present.It is interesting to notethat the same bases are, as might perhaps have been anticipated,present in the extract obtained from both sources, that is, meat and yeast,but in different proportions. I n this connection, the results of theanalysis of a number of commercial extracts of both kinds by Graffwill be studied with interest, as they probably represent the mostaccurate existing analysis of these products. Food chemists will alsoread with considerable interest a paper by Qrindley 3 which contains avery considerable number of analyses made with the object of elucidat-ing the chemistry of the proteids and other nitrogenous constituentsexisting in meats.I n connection with the detection and estimation of preservatives infood-stuff s, two recent communications are of importance, inasmuch asthey show the need for the exercise of caution in drawing conclusionsfrom the presence of very small quantities of certain substances whichhappen t o be widely used as preservatives.Thus Allen has determinedthe boric acid naturally existing in many fruits (and in consequence infermented beverages, such as cider, prepared from them), and has foundquantities as great as 0.016 per cent. Desmoulihe again has calledattention to the existence of traces of salicylic acid in cherries, andthus supplies another example of the somewhat widespread occurrenceof that substance in the vegetable kingdom.Treadwell and KochG deal at some length with the estima-tion of fluorine in wine and beer, and advocate, in the formercase, a modification of Rose’s method.For the estimation of boricacid in milk, butter, and other foods, Partheil and Rose recommend agravimetric method in which the acid is extracted with ether. Thequestion of the detection and identification of artificial colouringmatters in articles of food is of considerable importance to the Foodanalyst in view of the ever increasing use of the aniline and othersynthetical dyes, some at least of which cannot but be regarded asobjectionable for such a purpose.The work of Forminek amongothers which was undertaken with the object of showing the relationbetween the constitution of certain dyes and their absorption spectrahas incidentally shown that a properly conducted spectroscopic observa-tion may often supply information which cannot well be obtained byany other known method. I n this connection, attention may be directed1 Zeit. Nahr. Gentmi?&., 1904, 7, 257 ; 8, 227.Ibid., 389.Analyst, 1904, 29, 301.J. Amer. Chem. SOC., 1984, 26, 1086.J. Pharin. Chim., 1904, 19, 212.Arch. Phnrm., 1904, 242, 477. ti Zeit. anal. Chm., 1904, 43, 469166 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.t o a paper by Onfroy on the identification of the colouring mattersin absinthes, since, although based upon methods already known, it maybe of use in connection with the examination of some other alcoholicbeverages.Much analytical work bearing on the composition andsophistication of well-known drugs has been done during the year, butin many cases the results are scarcely of sufficient general interest,even if space permitted, to justify special reference to them here.Thorpe and Holmes2 describe a method for the estimation of methylalcohol in the presence of ethyl alcohol, which is capable of being use-fully applied to the detection and approximate estimation of methylatedspirit in tinctures and other medicinal preparations. Exception istaken to the B.P. test for cinchonidine in quinine by Paul,3 whosuggests an alternative method, and attention may be called in thisconnection to a paper by Lkger4 on the determination of quininein the presence of other cinchona alkaloids.Dowzard5 has slightlyamended the process for the determination of morphine in opium andtincture of opium which he recently proposed as a substitute for theB.P. method, the latter being in his opinion not only clumsy, butinaccurate. While dealing with the analysis of alkaloidal materials,reference may be made to a useful paper by LBgerG in which methodsare given for the assay of nux vomica, Ignatius bean, ipecacuanha, andcinchona bark. Comparatively little advance has been made duringthe year in connection with the analysis of wines and other fermentedbeverages. Gugliemetti and Coppetti 7 have suggested a method for theestimation of glycerol in wine, which appears to be a useful modifica-tion of the well-known process involving extractions with ether andalcohol. Ley* has suggested the application of his zinc precipita-tion method t o the estimation of tartaric acid, Robin details amethod for the estimation of citric acid, and Mathieu 10 describes a newprocess for the estimation of aldehydes.The analytical chemistry ofcider vinegar is dealt with in a very useful paper by Leech andLy t hgoe.llAs a result of a magisterial decision under the Sale of Food andDrugs Acts in connection with the composition of brandy, the analysisof that spirit has received a considerable amount of attention duringthe past year in this country. The methods adopted have been largelythose in use in the Paris Municipal Laboratory, and described in theManuel Pq.atipue de I'ccnalyse des alcools et des spiritueux, by GirardJ. Pharm.Chim., 1904, 19, 99.Pharm. J., 1904, 18, 397.Ann. Chim. anal., 1904, 9, 11.Anqz. Chivz. anal., 1904, 9, 453.l1 J. Amer. Chem. Xoe., 1904, 26, 375.2 Trans., 1904, 85, 1.3 Chemist and Druggist, 1904, 65, 428. J. Pharm. Chim., 1904, 19, 427.J. Pharm. Chim., 1904, 19, 479.8 Pharm. Zeit., 1904, 49, 149.10 Bev. intcrn. Falsif., 1904, 17, 43ANALYTICAL CHEMISTRY. 167and Cuniasse. Windisch 1 makes an important contribution t o thissubjectj and interesting articles dealing with the same matter will befouad in the J. P l ~ ~ r n . Chim., 1904, 19, 481 and 593. It is clear,however, that chemical methods alone are a t present incapable ofindicating with certainty the source or origin of a sample of spirit, orof distinguishing in many cases between the genuine and 6he carefullyprepared factitious article.I n August last the Committee appointed by the Council of the RoyalInstitute of Public Health to consider the standardisation of methodsfor the bacterioscopic examination of water issued their Report.Thisdocumentj2 suggesting as it does “standard” methods for the collectionof samples, the preparation of nutrient media, and the identificationof certain specific bacteria, cannot fail to be of considerable interestto all analysts who are called upon to express an opinion on the purityof water.Appucratus.Within the limits assigned to this Report it is not possible to referto all the new pieces of apparatus which have been devised anddescribed during the past year, and the following list thereforecontains references to those appliances alone which appear to be mostgenerally useful.u A simple thermostat for use in connection with the refractometricexamination of oils and fats.” T. %. Thorpe (J. Chem. Xoc., 1904,85, 257).‘‘ An instrument for determining the degree of turbidity and depthof colour of solution. (Diaphanorneter.) ” J. Konig (Zeit. Nulur.Genussm., 1904, ’7, 129 and 587).‘‘ The nephelometer, an instrument for detecting and estimatingopalescent precipitates.” T. W. Richards and R. C. Wells (Amer.Chem. J., 1904, 31, 235).‘‘ Improved gas absorption apparatus.” 0. Scheur (Chem. Zeit.,1904, 28, 598) and N. Wolff (Chem. Zeit., 1904, 28, 644).“ A new lamp for colour matching.’? W. M. Gardner andA. Dufton (J. SOC. Chem. Incl., 1904, 23, 598).(‘ A new fractionating apparatus.” J. Houben (Chem. Zed., 1904,28, 525).‘‘ A new explosion pipette.?’ 0. Pfeiffer (Cl~rn. Zeit., 1904, 28,686).‘‘ A new apparatus for the steam-distillation of small quantities ofliquid.”“ A measuring flask with specially graduated neck for thePozzi-Escot (BUZZ. Xoc. chim., 1904, 31, 932).Zeit. Nahr. Genussm., 1904, 8, 465.JotmmZ of State Mediciue, 1904, August168preparation of standard solutions.” A. Goske (Chem. Zeit., 1904,28, 795).‘‘A shaking and stirring apparatus for use with heated flasksattached to reflux condenser.”“ A new double surface condenser.” H. E. Burgess (Chem. News,1904, 90, 249).‘‘ An improved form of Kipp’s apparatus.’’ R. J. Friswell (Chem.News, 1904, 90, 154).“ A comparative refractometer scale (slide rule) for use with fatsand oils.” A. E. Leech and H. C. Lythgoe (J. Arner. Chem. Xoc., 1904,26, 1193).AntonLandsiedl (Chem. Zeit., 1904, 28, 643).ANNUAL REPORTS ON THE PROGRESS OF CHEMTSTKXIJ. W. Briihl (Ber., 1904, 3’7, 918).“ Improved measuring tube for Dumas’ nitrogen process.”The greater part of the labour involved in the preparation of thisReport has been due to the difiiculty of selecting from the veryextensive literature of the subject those communications whichappear to be most deserving of notice. I n a review covering so vasta field it is perhaps too much to hope that errors of judgment havebeen entirely avoided, and within the limits of this Report it wasinevitable that many useful observations should have been leftunrecorded. The author has, however, striven to present a &sum;of the work of the past year, containing references to the moreimportant analytical investigations, and one in which regard hasbeen had not only to scientific merit, but to utility and practicalimportance.ALFRED C. CHAPMAN

ISSN:0365-6217    

DOI:10.1039/AR9040100148

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

PHYSIOLOGICAL CHEMISTRY.THE majority of the abstracts in the Journal of the ChemicalSociety which deal with subjects of bio-chemical interest have beenprepared by me during a period of nearly twenty years. I may,therefore, be pardoned if I preface the first of these Annual Reportsby a brief comparison of the condition of physiological chemistryat the present day with what it was some years ago.If even a superficial survey of modern physiological literatureis taken, one is at once struck with the great preponderance ofpapers and books which have a chemical bearing. Chemistry iscoming to be recognised more and more as one of the foundationsof physiology, and a mainstay of the art of medicine. From thispoint of view, the physiological journals of to-day contrast verymarkedly with those of thirty, twenty, or even ten years ago.The sister science of chemical pathology is making similar rapidstrides. When, in 1886, my duties as an abstractor began, therewas only one journal (Hoppe-Seyler’s Zeitschrif t ) which dealt withchemico-physiological subjects only, and a dozen, or at most twenty,abstracts per month was my output.Now there are several newjournals devoted to the subject, and in 1903 a Centralblatt,edited by Dr. C. Oppenheimer, dealing with bio-chemistry alone,made its appearance. The number of abstracts prepared eachmonth is seldom under fifty, and usually much exceeds thatnumber. Even then it is only possible to deal with the principaljournals, and if time permitted the number might be easilydoubled. I n some Universities the importance of biologicalchemistry is recognised by the foundation of chairs which deal withthat subject; and, although in the United Kingdom, owing mainlyto lack of funds, this aspect of the advance of science is not veryevident, there are signs that the date cannot be far distant whenevery well-equipped University or University College will followthe example set us at many seats of learning on the Continents ofEurope and America, and at Liverpool.Chemical physiology is rapidly becoming a, more exact science.I caa perfectly well remember the time when those wh170 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.devoted their time to the chemical side of biology mightalmost be counted on the fingers of one hand, and whenchemists looked with scarcely veiled contempt on physiologicalchemistry ; they stated that physiologists dealt with messes,impure, non-crystalline materials, and, therefore, anything inthe nature of correct knowledge was not possible.There was agood deal of truth in these accusations, and if physiologists to-daycannot say that they have changed all that, they can a t leastassert with truth that they are changing it. This is due t o a grow-ing rapprochement between chemists and physiologists. Most ofthe rising generation of physiologists now go through a thoroughpreliminary chemical training; and, on the other hand, there is agrowing number of pure chemisteof whom Emil Fischer is oneof the most eminent-who are recognising the importance of asystematic study of substances of physiological interest.A strik-ing instance of this is seen in the progress of our knowledge of thecarbohydrates, which has culminated in the actual synthesis ofmany members of the sugar group. Another is the accurate in-formation we now possess of the constitution of uric acid. Thechemical constitution of proteid or albuminous substances is stillfor the future. I n spite of the overwhelming importance of thissubject, the correct knowledge of which underlies so much of vitalphenomena, chemists and physiologists long refrained from anyattempt to unravel the mystery of the proteid molecuIe. But, littleby little, the puzzle is being solved; many of the proteids have nowbeen crystallised ; the simplest proteids, the protamines, are yieldingtheir secrets t o Kossel and his co-workers; Emil Fischer hasbrought his great experience t o bear on the problem, and importantdevelopments are eagerly expected.When this great conquest oforganic chemistry is accomplished, physiologists will be furnishedwith new light on most of the obscure spots in physiological science.Already one outward and visible sign of the greater exactitudecoming over proteid chemistry is seen in the altered position nowoccupied by abstracts of papers dealing with it in our journal.Such abstracts fill a humble place at the end of the organicchemistry section; they have been elevated from the more outlyingdistricts of Part 11.Before it is possible to attempt a synthesis of the proteid mole-cule, a preliminary necessity is a correct knowledge of its analyticalcleavage products.One of the most instructive methods of accom-plishing such cleavage is by means of proteolytic ferments. Accord-ing to the doctrine of Kiihne, peptic as well as tryptic diges-tion leads to the formation-first of primary albumoses, which arethen broken up into secondary albummes, and these in turn intPHYSIOLOGICAJA CHEMISTRY. 171the still smaller molecules of peptone. He further differentiatedbetween the peptone produced in the stomach-amphopepton-and that produced during pancreatic digestion. I n the former, twohypothetical groups were still united, of which one-the hemi-group-could be further decomposed by trypsin, whilst the other-theanti-group-was resistant. Tryptic digestion, according to him,thus led to an antipeptone, which differed from amphopeptone inthe absence of the hemicomplexes, these having been decomposedwith the formation of amino-acids.These views have been modified by recent investigations.Through the Strasburg school, in particular, it has been shownthat the number of primary products of peptic digestion is largerthan Kuhne supposed, and that in quite early stages in digestionsubstances are formed alongside of the albumoses which no longergive the biuret reaction, and these have been termed peptoids.Thesecondary albumwes, which, a t a later stage, are derived from theprimary, are also numerous ; following this, products are formedwhich differ from the albumoses in the fact that they cannot be pre-cipitated by saturation with ammonium sulphate in either acid,alkaline, or neutral media.Kiihne himself doubted the unity of antipeptone, and it has nowbeen demonstrated that amphopeptone and antipeptone in theoriginal meaning of the words do not exist.These hypotheticalsubstances represent mixtures of various fundamental constituentsof the proteid molecule, some of which give the biuret reaction.These products, moreover, are the same whether the decompositionof the molecule is accomplished by pepsin or by trypsin. Theessential difference between the two enzymes lies in their velocity ofreaction; in this respect trypsin is more active than pepsin.With the destruction of the original concept of peptone, interestcentres in the fine1 products from which the tissue proteids mustagain be constructed.These comprise the mono-amino-acids,leucine, alanine, glycine, aminovaleric, glutamic, and aspartic acids ;the diamino-acids, or hexone bases, wginine, lysine, and histidine ;the sulphur-containing substances, cystin ; the aromatic amino-acids, tyrosine and phenylalanine, and certain pyrrolidine deri-vatives. They represent various nuclei which exist preformed inthe albuminous molecule, and are linked together in more or lesscomplex groups. The combinations of amino-acids have beennamed peptides by E. Fischer, and he has shown that substances ofthis kind are formed during proteolysis and occupy a position inter-mediate between the albumoses and the end-products.Among theresults of tryptic digestion of fibrin, egg-albumin, and other pro-teids, he has demonstrated the presence of polypeptides at a tim172 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.when the amino-acids of which they are composed are also partlypresent in the free state.l How far the primary product.s of pro-teolysis are absorbed and contribute to the formation of the proto-plasmic proteids is uncertain, but evidence is accumulating toshow that both during gastric and intestinal digestion the albu-minous molecule is more completely broken down t o its fundamentalcomponents than was considered to be the case by Kuhne and hisschool. I f this is so, the various proteids of the living body mustbe formed synthetically from comparatively simple substances in amanner quite analogous t o the formation of fat and of glycogen.Among others, Lowi has shown that i t is possible to maintainnitrogenous equilibrium in dogs by feeding them with the crystal-line cleavage products resulting from pancreatic proteolysis whichno longer give the biuret reaction, and, although his work has beenquestioned in some of its details, his main contention appears tohave been proved.We are thus presented with an entirely newconception regarding the origin of the most important chemicalmaterial of living substance.I have interpolated this brief account of our new ideas concern-ing proteids a t this point for sake of convenience, but beforepassing on to the consideration of the literature of the past year, Idesire still further to clear the way by noticing some other featureswhich characterise modern researches in the chemical fields ofphysiology.The first of these is the increasing importance which physiologistsrecognise in a study of inorganic chemistry, The importance ofwater, of oxygen, of various salts and acids need hardly be men-tioned.The discovery of argon and its allies in the atmospherehardly touched physiology a t all ; whether these elements have anybio-chemical interest is still a question for the future. But withthe discovery of radium there is a different story to tell, and theproblem whether the emanations from radioactive substances havesufficient penetrative power to make them of real use in the thera-peutic sense is attracting world-wide attention. The importanceof oxygen for life is one of the truisms of the physiologist. Howmuch he has still to learn about oxidation in the body was amplydemonstrated a t a discussion on this subject held at the recentmeeting of the British Association a t Cambridge.The r6Ze ofoxygen in the body is not so simple as it is in the ordinary com-bustion of a candle; for, although oxygen is important in theformation of such products of decomposition as carbon dioxide, itappears to be still more essential in the opposite phase of meta-1 On the synthesis of polypeptides, see E. Fischer and Suzuki, Absti., 1904,ii, 771PHYSIOLOGICAL CHEMISTRY. 1’73bolism, the building up of living materials. It is proverbially moredifficult to build up than to destroy, and so it is possible that theagents called oxydases (provisionally grouped with the enzymes) mayexercise what influence they possess on this more difficult side ofthe metabolic process.The new branch of inorganic chemistry, called physical chemistry,has given us entirely new ideas of the nature of solutions, and theionic theory is one of fundamental importance in the study of suchquestions as osmosis.I n a brief review of this kind it is impossibleto do more than indicate a few of the questions of physiologicalinterest touched by the physical chemist. The old experiments ofRinger on the importance of inorganic salts on contractile tissueshave been amply verified, and are now interpreted as due tom ionicaction.Loeb, Mathews, and their collea’gues in America, have goneso far as to consider that the process of fertilisation and the natureof the nerve impulse are to be mainly explained on an electrolyticbasis, and up to a certain point have supported their views withexperimental evidence. But whether such sweeping and revolu-tionary ideas will stand the test of further verification cannot bestated with certainty at present. There is always danger that theimportance ‘of a new idea may be overestimated; the ionic theorymay be a universal cure for all our previous ignorances, but thechances are that it is not. It has its proper place, and an im-portant place, into which it will ultimately settle when the glamourof novelty wears off.A t any rate, the mere suggestion that sucheminently vital phenomena as excitability, rhythmicality, repro-duction, and nervous action are either in whole or in part due tothe physical action of inorganic substances indicates the undesir-ability of postulating the existence of any special mystic ‘‘ vitalforce.”It is, however, not correct to speak of physical chemistry as in-organic only. Many eminent chemists consider that the futureadvance of organic chemistry also will be on the new physical lines.It is impossible to forecast where this will lead us to; suffice it tosay that not only physiology, but also pathology, pharmacology, andtherapeutics will receive new accessions t o knowledge, the im-portance of which will be enormous.During the past year thelast volume of Hamburger’s great work 1 on the bearings of a know-ledge of osmotic phenomena on medical learning has appeared, andthe fact that three large volumes have been necessary to containa discussion of the questions involved is an index of the rapidgrowth this aspect of the matter has undergone. Whether proteidsOsmotischer Druck wid Ionc~~teh~c i?t den naed. TVi.ssenschaften. By H. J.Hamburger. Wiesbarleil : J. F. Bergmann. 3 vols1’74 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.exert osmotic pressure is a moot point with the physiologists;Waymouth Reid answers the question in the negative.lThe next general feature which has characterised bio-chemicalresearch, especially during the last few years, is the im-mense a’mount of work which has been carried out in connectionwith theories of immunity. The name of Ehrlich will be im-mortalised in this connection, and his discoveries bid fair in thefuture to be reckoned with those of Newton, Darwin, and Pasteur.Whatever may be the fate in the future of his side-chain theory,there can be no doubt that it has been the means of stimulatingresearch and so leading to important discoveries.Without enteringinto details, the theory may be regarded as an expansion of thesimile of “lock and key,” which Emil Fischer first put forward inrelation to ferment action. Bacteriolysins and similar substancesare dual bodies, consisting in part of a ferment-like material nowknown as the complement, and a second substance called the ambo-ceptor which anchors it on to the material t o be acted upon.This work has not advanced yet into the regions of exactchemistry.The substances in question are, doubtless, proteid orproteid-like in their characters. No one has yet seen an antitoxin,a hzemolysin, an agglutinin, a precipitin, and the like in a state ofpurity, even in solution; but they are there, and it is only a matterof hard work in the future to isolate them successfully. The im-portant discoveries that have centred around this work are not onlynumerous, but many are of incalculable benefit to mankind. Thuswe have been provided with a certain cure for the terrible maladydiphtheria, and for that scourge of many tropical climes, snakebite.Various forms of protective inoculation (for plague, typhoid,&c.) have been introduced, although in some cases the matter isstill in the experimental stage. We have been furnished with thenew biological test for bloold, and are so enabled to distinguish theblood of diff erent animals, which the microscope, spectroscope, andchemical testing were previously unable to do. New light has beenshed on several obscure physiological questions, especially in regardto ferment action. Ferments are also1 probably dual bodies. Thisfirst became a certainty in relation to Pawlow’s discovery of entero-kinase. The pancreatic juice, if is now known, contains no trypsin.Claud Bernard, the earliest to examine pancreatic digestion withprofitable results, entirely missed its pmteolytic action.The sub-stance it contains is the mother substance of trypsin, trypsinogen.When it meets the succus entericus in the intestine, trypsin isliberated, and the result is a powerful proteolytic agent. Pawlowregards enterokinase as itself a ferment, and speaks of it as aAbstr., 1904, ii, 830PHYSIOLOGICAL CHEMISTRY. 175“ferment of ferments.” Delezenne, on the other hand, regards it inthe nature of an amboceptcur. Starling upholds Pawlow’s viewwith many convincing experimental arguments. Which isright must be left for the present. The discovery of enterokinasehas led to the search for, and in some cases to the discovery of,other kinases, and a whole field of exploration as to the action oneferment has on another has been opened up.Then there is no doubt that there are anti-ferments; we havepapers now dealing with antirennet, antipepsin (for example, Ascoliand Bonfanti on antidiastases,l Cathcart on antitrypsin 2, and thelike.The old difficulty of why the alimentary canal does not digestitself is thus capable of a rational explanation.The same ideas underlie recent work on the vexed problem ofblood coagulation ; Morawitz and others may have introduced sometemporary confusion by the coining of new words, but the principleof the new theories is that the thrombin or fibrin-ferment requiresfor its activity something in the nature of an amboceptor, or akinase, or both, and that the presence of antithrombin will explainwhy fibrin-ferment is not always effective in promoting fibrin form-ation.These are just a few instances to show that the explana-tions of ferment action and ferment inhibition are becoming intel-ligible.The discovery of secretin belongs to the same category of inexactchemistry as that of anti-toxins and anti-ferments, but i t is none theless important, and its inexactitude is the fault of its youth, which!it will outgrow. A chemical substance is produced owing to theaction of acid in the intestine; this substance is absorbed, carriedby the blood to the pancreas, and there stimulates the flow of pan-creatic juice. This substance is named secretin by its discoverers,Bayliss and Starling ; it is an organic substance of comparativelysmall molecular weight, but that is all we know yet from thechemical point of view.Whether there are other similar secretinsconcerned in the stimulation of other secretions, such as milk, i t isimpossible to forecast; but they are being eagerly sought after.For many years we have been too much in the habit of regardingthe telegraphic system of the body, the nerves, as the sole meansof communication between its various districts ; the slower mes-senger, who is equally useful, the blood, has been rather apt to havethe value of its carrying properties underestimated.I f now we turn to the more immediate object of this review, weshall find in the literature of the past year papers illustrating allthe general features of progress to which I have devoted the intro-duction. We shall, moreover. find instances of the extension ofAhstr., 1904, ii, 827.Ihid.. 8331’76 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.chemical work in the elucidation of pathological problems, even inconnection with obscure nervous diseases. We shall find similarprogress in the region of comparative bio-chemistry, and the branchof physiology called pharmacology looks as thoagh the time willsoon arrive when it will be bigger than the parent tree.It will, of course, be impossible to deal with every paper; thoseI shall select for comment will only be the most striking, or thoseof most general interest. It is possible that another writer mighthave made a different selection, but it will be my endeavour not toallow my personal predilection for certain subjects of research toobtrude itself too forcibly.To reduce the large amount of materialto something like order, I shall arrange what I have to say undergeneral headings.Proteids und their Decomposition Products.The particular class of proteids which has attracted the specialattention of investigators recently is that of the nucleo-proteids;some papers have dealt with their physiological action, others withthe more strictly chemical side of the subject. In the formergroup the work of Prof. MacWilliaml deals with the effect ofinjecting nucleo-proteids intravascularly. The usual effect of suchan injection is death, due to intravascular coagulation. Clotting,however, does not occur in blood shut up in an artery or vein; itmust, therefore, be in the capillary area that the conditions forinducing fibrin formation are present.On the other hand, it iswell known that injections of small amounts of nucleo-proteid leadto what Wooldridge termed the ‘ I negative phase,” that is, the bloodis rendered incoagulable. MacWilliam finds that if the lower half ofthe body is cut off from the circulation, this does not occur, andsuggests that the anti-substances responsible for the negative pbaseare generated in the abdominal viscera. Another interesting pointhe noted was that the exophthalmos, which is such a prominentsymptom in death from nucleo-proteid injection, is due tohzemorrhage into the orbit.The quantitative relationships of the blood proteids have formedthe subject of several papers; thus Lewinski gives a large numberof estimations of the plasma proteids in different animals, and inman under normal and pathological conditions; the effect of variousdiseases appears to be very slight, and inanition, a condition whichcertain older observers stated led to a great reduction in the amountof serum-albumin, produces in dogs a very small decrease of thisproteid.I n experimental infections with the pneumococcus andstreptococcus, Langstein and Mayer3 find a great increase in totalAbs.fr,, 1904, ii, 195. lbid., 183. Ibid., 184PHYSIOLOGICAL CHEMISTRY. 177proteid, and in the relative amounts of the globulins (fibrinogen andserum globulin).We must, however, note that the time-honoured classification ofalbumins and globulins seems in danger of disappearing. Theartificiality of the dist4inctim wm first mooted by Starke two orthree years ago; Moll 1 now states that by simply warming serumto 56-60°, the globulin is increased at the expenbe of thealbumins, hydroxyl ions being regarded as the cause of the change.The old statement that albumoses are present in normal bloodduring digestion has been recently reaffirmed by Bergmann andLangstein; they find the quantity, although small, is of appreci-able physiological importance.But, as the method adopted did notexclude the possilbility of the formation of hydrolytic products, thisconclusion sholuld be regarded with caution. Abderhalden andOppenheimer have arrived a t the opposite resultA large number of papers deal with the chemistry of nucleic acid,and the difficulty of this work is accentuated by the numerousacids included under that name.Levene and his colleagues4 havestudied the decomposition of nucleic acid from varioas organs byvarious agents; thus, from the nucleic acid of the testis, on hydro-lysis with 1 per cent. sulphuric acid, they olbtained mainly guanineand adenine; by the use of stronger acid at a high temperaturethey obtained thymine and cytosine. The purine bases appearto be easiIy removable by weak acids, the pyrimidine bases are morefirmly fixed in the molecule, and require more drastic measures todislodge them. According t o B ~ r i a n , ~ the purine bases in nucleicacid are combined with phosphoric acid through the nitrogen atomin position 7.These are a few instances of the sort of work now inprogress, which will in time result in a knowledge of the constitutionof the nucleic acid molecule. At present, however, in spite of theimportance of nuclein and nucleates in the composition of the livingcell,'j there is much uncertainty even as regards the empiricalformulae of these substances.'Tryptophan is an instance of a proteid cleavage product in whichresearch has at last definitely made out the constitution. Thismaterial in the proteid complex is responsible not merely for thebromine reaction, but also for Adamkiewicz's reaction. Hopkinsand Cole, to whom we owe the discovery, assigned to tryptophan thename a-aminoscatoleacetic acid and the formulaAbstr., 1904, i, 356.Ibid., 1904, i, 358, 956.Kostytschew, I.Bang, ibid., i, 127.]bid., ii, 826.Ibicl., 1904, i, 126, 955 ; ii, 495. :' /bid., ii, 623.ti I. Baug, ibitl., ii, 428.VOL. I. 178 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.but Ellinger has shown that the formula is more probablyNH<z&>C* CH( C10,H) CH,*NH, ,land that tryptophan is therefore indoleaminopropionic acid.Osborne and Harris point out that the intensity of the tryptophanreaction with different proteids indicates that the proportion ofthis substance yielded by proteids differs considerably. Tryptophanalso has been shown to be the parent substance of kynurenic acid(Ellinger), and is, further, the cause of Liebermann's colour test forp r ~ t e i d s . ~Another product of proteid decomposition, urinary indican, hasrisen into prominence owing to polemical discussions as to itsorigin, and the best methods of estimating it.4 There seems, how-ever, but little doubt that tryptophan is an intermediate stage inthe formation of indican.Monfet attributes Ehrlich's diazo-reaction in urine to indican, but this is apparently a mistake.GPolemics have also centred around the ureine of W. 0. Moor.'This autho'r maintains that the urea of the urine amounts to onlyone-half, or even less, of what is usually stated to be the case, theother half of the nitrogen being contained in this new substancecalled ureine. Ureine seems destined to fall into the list of for-gotten materials. Among other investigators, Gies points outthat it is a mere mixture of different organic and (mainly) inorganicconstituents of the urine ; urochrome forms a large proportion ofthe organic constituents p r e ~ e n t .~IIamogloBi.n.-A most interesting and suggestive piece of workon blood pigments has been carried out by P. P. Laidlaw.lo He hasshown that even dilute acids in the absence of oxygen will lead tothe formation, not of hEmatin, but of hsematoporphyrin. The factthat oxygen confers stability on the iron of the blood pigment hadbeen previously pointed out by HoppeSeyler, although this wasdenied by Nencki and Sieber. By quite simple treatment, the ironmay be replaced in haematoporphyrin, and haematin is thus syn-thetically obtained. If copper is similarly introduced into thehaematoporphyrin, a pigment is obtained having all the charactersof turacin, the red pigment of the feathelrs of the plantain-eatingbirds.Abstr., 1904, i, 639.Ibici?., 125. Cole. ibid., ii, 103.Hervicux, ibid., 6 3 ; R011111;t, ibicl., 102; Monfet, ibid., 63, 102; Maillard, ibid.Ibid., 63, 194.Ibid., 192, 274. Zbid., 192. Haskins,ibicZ., 754. '" Ihid., i, 1067.193 ; Underhill, ibid., 193, 754 ; Rosenfeld, ibid., 193 ; Salkowski, ibid., 753.Maillard, ibid., 194PHYSIOLOGICAL CHEMISTRY. 179Enzymes.General.-The action of electrolytes on ferments has been thesubject of a paper by Cole.1 Anions other than those of hydroxylaccelerate, whilst cathions and hydroxyl ions retard, the activity ofamylolytic ferments. We may place in the same category the workof Arrhenius 2 on the physical chemistry of agglutinins, which showshow the results published previously by Eisenberg and Volk may beemployed quantitatively.The combined action of ferments is a branch of research openedup by Pawlow’s discovery of enterokinase.For many years pre-vious to this, however, Schiff and Herzen had insisted on the im-portance of the spleen in promoting the efficiency of pancreaticaction. The experiments of Levene and Stookey 3 corroborate theview that the spleen facilitates the transformation of trypsinogeninto the active enzyme. They were unable to detect any similaraction of the spleen on the liver.The most striking statement in the same direction has beenCohnheim’s announcement that the pancreas facilitates the com-bustion of sugar in the muscles.I f this occurs within the body asthe result of an internal secretion of the pancreas, we are providedwith an explanation of the diabetes that follows extirpation ofthat organ. T’he active substance in the pancreas, which is respon-sible for this action, was at first placed among the ferments, butmore extended experiments have shown that the material inquestion is not destroyed by heat, and is soluble in alcohol.* Thesame, or a similar material, is present in the blood also.The lipase of the liver has been shown by Magnus to consist oftwo substances; one, the ferment, is not dialysable and is destroyedby heat; the other, the “co-ferment,” is dialysable and is notdestroyed by boiling. Cohnheim’s substance from the pancreas i svery similar to Magnus’s co-ferment.These facts point to the possibility of the nature of ferment actionbeing elucidated more fully in the future.Ferments are subtlesubstances, evading the search of the chemist to a large extent, butif the co-ferments are definite chemical materials soluble in alcoholthere is hope that their nature will be speedily determined, and sothe nature of their more evasive partners is likely to be made clearerat the same time. I n the same way, the idea that lecithin is oneof the materials concerned in the efficient action of snake venomholds out promise of corresponding Similar experi-Abstr., 1904, i, 131. Ibid., ii, 356. Ibid., 674.Did., 675. Bid., 6%.Preston Kyes, ibid., 431.N 180 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ments by Wells, in order to determine whether thyroid, kidney, andspleen influence the autolytic digestion of the liver, led t o negativeresu1ts.l The action of pepsin upon itself has been stated2 tolead to the formation of peptone.I f this is so, pepsin is a proteid.Felocity of Reaction.-The study of the velocity of enzymereactions is rapidly making the subject amenable to exact andmathematical treatment. An important series of papers on thisaspect of the problem is a t present appearing in the Proceedings ofthe Royal Society by E. F. Armstrong and C a l d ~ e l l . ~ We havehere an excellent example of how that rapprochement betweenchemical and physiological study, t o which I have alreadyalluded, is bearing important fruit.The numbers given show thatenzymes are more active than acids in promoting hydrolysis, butt‘his apparent activity is due to the greater affinity the enzyme hasfor the sugar, and that in reality the acid has the greater hydrolyticactivity.Blood Coagulation.-The cause of blood clotting has been a vexedquestion ever since physiology became a science, and still remainsso. As explained in the introductory portion of this article, anew note has, however, been recently struck in relation to thematter, and Morawitz has, in particular, advanced the view thatthrombin or fibrin-ferment is not a single substance. The a- andP-thrombins, as he terms its two components, have each precursors,a- and P-prothrombin, and matters are still further complicated bythe presence of antithr~mbin.~ The principal new idea introducedis that a kinase analogous t o Pawlow’s enterokinase is necessary t oeffect the change of the prothrombins into thrombins in addition tocalcium ions.5 Fuld and Spiro6 have used mainly birds’ bloodplasma in their work, and on the lines of the new theory seek toexplain the effect of muscle extracts, leech extract, peptone, andothek agents which hinder or promote coagulation, as the case maybe.The complexity of tihe subject has not been made less intenseby the introduction of a number of new terms (cytozyme, plasmo-zyme, holozyme, kc.); but this is a usual symptom of the embryoniccondition of new theories.Another worker a t blood-clotting is Leo Loeb; he has studied thesubject from the comparative point of view; ’ the so-called firstcoagulation in arthropod blood is an agglutination of corpuscles,analogous to that of blood-platelets in vertebrate blood; this isfollowed by true fibrin formation.Agglutination and fibrinformation are in all cases separate phenomena; the action ofAbstr., 1904, ii, 5’14./bid., i, 956-958, 1070. Ibid.. ii, 59.Ibid., 353. Ihid., 353. Ibid., 353.Herlitzka, ibid., 838.8 Jbid., 496PHYSIOLOGICAL CHEMISTRY. 181tissue extracts in promoting coagulation is regarded ax being dueto specific substances called coagulins, and not to adherent lymph.Erepsz*t.-This is an enzyme, first described by Cohnheim, in thedog's succus entericus, which has the power of splitting peptones intosimpler pro'ducts, although it has no action on the native proteids.It is also present in the succus entericus of herbivora.1 At firstCohnheim attributed great importance to this ferment, butKutscher considers it is comparatively feeble and unimportant.Starling, in this country, uses the term erepsin for the feeble proteo-lytic ferment which is contained in many animal tissues; it is, forinstance, present in fresh pancreatic juice, and is quite distinctfrom trypsin.Our knowledge of pancreatic wepsin has been in-creased by work performed by Vernon.2AutoZysis.-A very large amount of work is now being devotedto this subject. The following are the principal papers : -Hedin,on proteolytic enzymes of spleen and serum; Levene, on auto-digestion of liver and pan~reas,~ and of testis and spleen;Arnheim, on the favouring action of gelatin and carbohydrateson the autodigestion of the liver; W.Jones, on the autodigestionof thymus and suprarenal; ' Kutscher and Lohmann, on the end-products of pancreatic autodigestion ; s Lane-Claypon and Schryver,on the stages noticed in the progress of autolysis; and W. Jones,on autodigestion of nucleo-pr0teicls.l' There can be no doubt thatthe activity manifested by so many workers is warranted by theimportance of the subject. The tissue enzymes are important inthe metabolic cycle during life, and before it is possible to statewhat those functions are i t is obviously necessary to study whathappens when the ferments are allowed full scope after death.Thecurious thing about such enzymes is, that the majority act best inan acid medium, whereas the healthy tissues during life are alka-line. There can, however, be but little doubt that there are tem-porary phases of acidity, or acid foci in living cells, although thereaction of a mass of the tissue to the ordinary indicators may bealkaline. There is, further, no doubt that the nuclei of cells are themain centres for nutritional exchange, and so especial interestattaches to the results of autolysis of nucleo-proteids. Here it isfound that the end-products often differ markedly from those whichresult from hydrolysis by acids, and so Jones and Partridge l1searched for and found certain specific enzymes which account forthe difference.Fresh pancreas when subjected to autolysis doesnot yield adenine or guanine, and guanine when added to it istransformed rapidly into xanthine; the name guanase is bestowedNakayama, Abstr., 1904, ii, 425. a Ibid., 57& Ibid, 58.[bid., 188. Ibicl., 574. lbid,, 189, Ibid., 191.8 Ibid., 485. Ibid., 574. lo Ibid., 626. l1 Ibid., 838182 AJS’NUAL REPORTS ON THE PROGRESS OF CHEMISTRY.on the enzyme to which this change is due. Guanm is also presentin thymus and kidney, but not in spleen. Spleen contains anenzyme adenase, which, in a similar way, converts adenine intohypoxanthine.The search for such ferments acting on comparatively simplematerials was no doubt the direct result of the suggestive work ofKossel and Dakin, which led them to the discovery of arginase.This discovery is certainly one of the most striking and importantof the whole year’s work in physiological chemistry.Arginaselsplits arginine almost quantitatively into urea and ornithine.The failure of some observers to find arginine in the products ofthe autodigestion of organs is due to the previously unsuspectedaction of arginase, which must now be placed among Richet s urea-forming ferments. Arginase is found in the intestinal mucousmembrane, but more especially in the liver; nerves, thymus, andlymph glands are also active, but blood and muscles have practicallyno such action,2We therefore see that the study of autolysis has already hadthe important practical issue of enabling us to obtain a little deeperinsight into the metabolic processes that lead t o urea formation.Zmmunity m d Allied Problems.This is becoming a vast subject, with an extensive literature ofits own.I have already attempted to indicate its importance, butseeing how much has yet t o be done t o bring the subject within theregion of exact chemistry, the abstracts that have appeared do notdo much more than touch the fringe of the matter.At the recent meeting of the British Medical Association, a tOxford, a, most instructive discussion was held in the Section ofPathology on immunity and the questions related to it, and I can-not do better than recommend those interested in the subject t oread the account of that discussion published in the British MedicalJournal of September loth, 1904.’ All I shall attempt here is tocall attention t o some of the more important points noted in thepapers abstracted for the Journal of the Chemical Society.Venoms and Antitoxins.-Elliott, in conjunction with Sillar andwith F r a ~ e r , ~ has added to our knowledge of the action of thevenoms of the krait and of the sea snakes.I n both casesCalmette’s serum has no protective or curative value. W. H.Abstr., 1904, ii, 425, 840.See also Levene on hydrolysis of fresh and self-digested glands, ibid., 828. * Pp. 557 ct ssq. See also Bordet on “Chemical Theories of Immunity,” &sir.,1904, ii, 832. Ahtr., 1904, ii, 630PHYSIOLOGICAL CHEMISTRY. 183Wilson has furnished interesting facts concerning the mode ofaction of the venom of the scorpion. The tissue mainly affected ishhe muscular tissue, and the effect produced resembles that causedby veratrine.Desert animals likely to come in contact with scor-pions possess natural immunity against their poison, the resistanceof the Jerboa being 300 times greater than that of the guinea-pig.Curiously enough, however, the excised muscles of such animals areas readily affected by the venom as those of animals which are notimmune.Coming nearer home, it may be a relief to those who suffer frompollen poisoning or hay fever t o know that an antitoxin has beenprepared against this ailment, and that it gives excellent results.*A paper on the power of the liver to destroy diphtheria toxin3should also be mentioned.A ggZutirtins.-Gengou * and Gerard-Mangin and Henri haveworked at the subject of agglutination produced by various chemicalreagents.G. N. Stewart has made a very thorough study of thesubject, and not the least interesting of his results is that corpusclesfixed by formaldehyde nevertheless cause on injection a productionof specific agglubinins, and to a less extent of hEmolysins also; and,further, that such corpuscles are themselves agglutinated by specificsera.Precipitim.-Kraus and Levaditi -7 discuss the origin of thesesubstances, and conclude that they are produced mainly by theleucocytes. The most striking paper, however, is one by L. M011,~who has a conception of precipitins diametrically opposed to thatof most other authorities on the subject.According t o hirr, theproteid of the immune serum is the passive reagent; the precipitinit contains is the substance precipitated ; precipitin and precipi-tate are related t o one another in the same way as fibrinogen andfibrin. The whole precipitin question, and the results of theexamination of thousands of specimens of blood will be found mostably discussed in a recent book by G. H. F. N ~ t t a l l . ~Blood and Respiration.Apart from the subject of coagulation, which we have alreadyconsidered, the number of papers on the blood has not been great.There has been some discussion on whether glycerol exist% in theblood, a by no means unimportant point with regard to fat meta-Abstr., 1904, ii, 630.Bruntoii and Bokenham, ibid., 832.Ibid., 496. Ibid.Ibid., 497. 7 I b i d . , 423. I b i d . , 184.Blood Irnwmnity. Cambridge Uiiiversitg Press. 1904.Glegg, ibid., 578184 ANNUAL REPORTS ON THE PROGXESS OF CHEMISTRY.bolism. Nicloux maintains that it is present, whilst Mouneyratdisputes the accuracy of Nicloux’s meth0ds.lLocke has improved his methods for keeping the excised mam-malian heart alive with oxygenated Ringer’s solution, and demon-strated the important effect which sugar has in increasing itsefficiency; of the sugars used, dextrose alone has any action in thisdirection, and evidence is adduced of the disappearance of part ofthe dextrose after some hours’ activity.2 Hering and Gross3 havecarried out somewhat similar experiments, and their results con-firm those published many years ago by Ringer in connection withthe frog’s heart, results which Loeb has shown are to be interpretedas due to the action of ions.We may place in the same category with these the researches ofZoethout on the effect of salts on muscular tissues, and on whatLoeb has termed ‘‘ contact irritability ”; of Lillie on the relationof ions to ciliary movement; and of Row on the effects of Ringer’sfluid on plain muscle, which are much the same as on skeletal andheart muscle.6 Muller and Ott have made attempts to resuscitatethe brain of animals by oxygenated salt solutions, as Locke,Kuliabko, and others have done with the heart, butfailed. ‘When the supply of blood to the brain ceases, thegrey cortex rapidly undergoes chemical changes, which cause itto react acid to litmus.The importance of a continual stream ofarterial blood is familiar to all, a slight diminution in the supplycausing unconsciousness.Experiments on respiration have been mainly limited to those onthe effects of altered atmospheric pressure. We now know thatcaisson disease is due t o too rapid “ decompression,” and the con-sequent liberation of gas bubbles in the blood.’ Work on the oppo-site question, the effect of rarefied air on the blood and respiration,has been mainly stimulated by MOSSO’S labours in his Monte Rosalab~ratory.~ T”he chief result of this work has been to confirm, oftenwith fresh details, the older observations that, the diminution ofpressure must be considerable to produce harmful or even detectableresults, and that the principal effect on the blood is an increase ofthe corpuscular elements.The sensitiveness of the nervous systemto the action of alcohol is diminished at great altitudes.I n this connection we must not omit to mention the importantwork which Beddard, Pembrey, and Spriggs have commenced on thegases of the blood during diabetes and diabetic coma; lo they haveAbstr., 1904, ii, 56, 270. Ibid., 422. Ibid., 55. 190,Ibicl., 273. Ibid., 190. 7 Ibid., 627. L. Hill, ibid., 54.MOSSO, ibid., 622, 757 ; Kemp, ibid., 183 ; Bartlett, ibid., 54 ; Durig, ibid., 270 ;Tissot, ibid., 495. lo lbid., 622PHYSIOLOGICAL CHEMISTRY. 185already shown that our ideas concerning the cause of diabetic comawill need revision.The part played by oxygen in the tissues is a moot point, and hasbeen so for a long time in connection with muscle.Similar ques-tions have arisen in connection with secreting glands and nervoustissues. Baas,1 working in Verworn's laboratory, has shown, in con-firmation of Baeyer and Frohlich, that oxygen is necessary for thecontinued activity of excised nerves, and that normal nerves in thebody probably participate in respiratory metabolism. The idea isnot new, for Waller some years ago brought forward circumstantialevidence in favour of the view that nerves produce carbon dioxidewhen in action.A paper which I find difficult to classify is Macallum's, onthe Palaeochemistry of the Ocean, but as I have alluded to theinorganic salts of the blood in this section, I place a brief noticeof it here.The paper ought to be carefully read, and even the longabstract I gave of i t 2 hardly does i t justice. I n the blood plasmaof vertebrates, the relationship of sodium, potassium, and calciumis strikingly like that which now obtains in sea-water; magnesium,however, is present in smaller proportion. This is due to heredity,and reproduces the condition of the sea-water at the date when acirculatory system first appeared. I f it were possible to determinethe proportion of the four elements in protoplasm, good groundsare adduced for believing that their proportion would be that whichobtained in sea-water in more distant ages before the developmentof the circulation.I n connection with digestion, the pancreas still maintains theinterest that the discovery of secretin stimulated. I n Starling'slaboratory, de Zilwa3 has examined the composition of the juiceobtained by secretin and by pilocarpine.I n the former case, thealkalinity is greater, but the total solids and the proteids are lessin amount. Bainbridge," working in the same place, has directedrenewed attention to what is called the adaptation of the pancreas.Weinland was the first to show that, on a milk diet, the pancreasrises to the occasion by producing lactase; according to Bainbridge,this is chemical adaptation, the lactose acting on the intestinalmucosa in such a way as to produce a material which, after absorp-tion, stimulates the pancreas to produce an unaccustomed enzyme.Glaessner has had the unusual opportunity of examining humanAbstr., 1904, ii, 576.Ibid., 495. Ibid., 574.Ibid., 424. Ibid., 270186 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.pancreatic juice, and confirms the work of Pawlow and others whohave mainly worked with the juice obtained from animals, withregard to the times of maximal secretion, and the necessity of itsbeing activated by the intestinal juice. The increased oxygenabsorption that accompanies pancreatic activity has been demon-strated by Barcroft and Star1ing.lGeneral Metabolism.-Atwater and his colleagues in Connecticutcontinue their monumental labours in the collection of statistics.2Another centre of activity on metabolic work in America is the YaleLaboratory, presided over by Prof. Chittenden.The long-estab-lished idea that a man requires a-minimum of 15 grams of nitrogenin his daily food is being seriously questioned; Chittenden himselfand his colleagues have maintained their health and equilibriumon much less3 It is, however, too early to state yet whether suchdeprivation will have any harmful effects. This question wm takenup originally by Mr. Horace Fletcher, who is stated to have curedhimself of dyspeptic and other troubles by lessening his proteidnutriment below what was regarded as the physiological standard,and has started a propaganda on the subject from the economicpoint of view; but in France two observers, Labbe and Morchoisne,4have even gone beyond Fletcher by subsisting on a proteid intakeof only 2 t o 3 grams daily for thirty-eight days.They state theirhealth remained good all the time, but the tables they publish showa loss of body weight. Succi and other fasting men also statedthey felt pretty well after no nutriment a t all for forty days.Rubner, another prominent investigator in the metabolic field, hasdone yeoman service in proving that the law of the conservation ofenergy holds good for the chemistry of living things; he was theearliest t o draw prominent attention t o the necessity of an investi-gation of the faxes, as well as of the other excreta in the con-struction of accurate metabolic balance-sheets. Among his fol-lowers, Lohrisch,5 in estimating the energy of the dejecta by meansof calorimetry, invariably found their heat value was greater thanthat reckoned from their chemical composition ; this is, however,capable of a simple explanation, namely, that a t present errors ofanalysis arise in the examination of such a complex mixture asfaxes; for instance, it is incorrect to consider that the etherealextract is all fat; it also contains lecithin and cholesterol.Thepurine substances in faxes have been estimated by Walker Hall;and Rockwood confirms the statement previously made by Burianthat the endogenous uric acid differs in different individuals, but3 Physiological Econonzy in Nutrition. By R. H. Chittenden. New York:Abstr., 1904, ii, 827. l b i d . , 186.F. A. Slater and Co. 1904. Abstr., 1904, ii, 498. Ibid., 428.Iiki., 358. Ibid., 673PHYSIOLOGICAL CHEMISTRI'.18'7remains remarkably constant, even on different diets in the sameperson.GZycogen.-Pfliiger's A r c h i v in general, and Pfluger himself inparticular, continue to pour forth voluminous papers on this sub-ject. A welcome exception to this rule is to be found in an admir-ably co'ncise article by Pfliiger, which gives the main steps in thenew method of estimating glycogen, originally introduced by Pavy,by means of strong potash.1 This new method has rendered most ofthe older estimations of glycogen in organs useless, and by it thissubstance has now been detected in many places where its existencewas previously unsuspected. Analytical details regarding theamount in the fetal liver have appeared during the year.2Loeschcke states that glycogen is free, not chemically bound in theorgans where it occurs, and the chemical and physical propertiesof absolutely pure glycogen have been described by Gatin-Gruzewska.*T h e Cerebro-spinal Fluid.-The phosphorised fat of the nervoussystem was originally described by Liebreich as protagon ; Hoppe-Seyler denied the chemical individuality of this substance ; Gamgeeresuscitated it ; Baumstark and Kossel supported Gamgee ; andlately Thierfelder and Lesem and Gies gave it what they consideredits death blow.Cramer has, however, again revived it, and shownthat it has a perfectly constant composition. It is, moreover, oneof the few substances from the brain that can be obtained in a definitecrystalline form. Its molecule, however, is too heavy t o containmore than a small fraction of the phosphorus of the nerve fat, andno one denies that the bulk of the phosphorus is contained in thesmaller molecules of lecithin, kephalin, and other phosphorisedcomponents.6 All these substances resemble one another, andresemble proteids in being in that condition of unstable chemicalequilibrium we term metabolism ; and all, moreover, yield amongtheir decomposition products the alkaloidal material, choline, I nvarious nervous diseases, the presence of choline in the cerebro-spinal fluid and blood is an indication of organic breakdown; kata-bolism exceeds anabolism.I n nervous diseases which are termedfunctional, no such evidence of decay is forthcoming. Hence, indifficult cases of diagnosis, the test for choline comes t o the aid of thepractical physician, as Mott and I were the first to point out.InGermany the question has been taken up by Donath, who has con-firmed our results, but somewhat modified the test with platinicchloride, on which he places most reliance.' He also finds that,Abs-str., 1904, ii, 595. Yfliiger, ibid., 427. Ibid., 576.Ibid., i, 838. ' Ibicl., 462.For recent quantitative work, see W. Koch, Abstr., 1904, ii, 498.Ibid., 63188 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.with the decomposition of phosphorised fats, the amount of phos-phates rises in the cerebro-spinal fluid.1 I n America similar resultshave been obtained by Dana and Hastings? and in his latestpaper, Donath quotes several other confirmatory observations.There have, on the other hand, been some investigators who appearas critics; Mansfield’s statement? that the crystals obtained byDonath are simply due to inorganic chlorides, has been amplyrefuted by Donath; Allen, who, in conjunction with French, beganas a d o ~ b t e r , ~ has later become a convert to the true faith;6 he,however, regards the test with iodine, with the modifications he hasintroduced, as more trustworthy than the test made with platinicchloride.Pharmacology.The number of papers relating to the physiological action ofdrugs is almost i ~ s great as the number of drugs, and the termPharmacology includes also the action of other chemical andphysical agents on the living organism.I n the greater number ofcases, I fear, I must adopt the subterfuge of referring inquirers tothe forthcoming index (Trans., 1904); all I can attempt to do hereis t o allude to a few of the most prominent or interesting of the agentsinvestigated.Among those recently discovered, the Rontgen rays andradium have attracted considerable attention.W. B. Cannon ’ hascontinued his useful work on digestion by means of Rontgen rayshadows, and by mixing the food with bismuth has been able toestimate the rate of discharge from the stomach into the intestines.His main conclusion is that acid in the stomach is the greatstimulus for the opening of the pyloric orifice, and in the intestinefor its closure.So much was huped for at first in the direction of cure of cancer,&c., by means of these rays, that it is important t o call attentionto their danger; the skin irritation caused by constant exposure tothe rays sometimes leads to the formation of cancer, and, as in thecase of Edison’s assistant, may thus be fatal.Radium emanations may be found curative in the future; up tothe present, investigators have mainly succeeded in demonstratingtheir injurious effects.The penetrative power of the emanationsthrough the skin appears to be slight, SO there is little hope ofemploying them for the destruction of micreorganisms or otheragents that set up deep-seated disease. The principal papers on thephysiological effects of radium have been the following during t h sAbstr., 1904, ii, 628. Ibid., 359. .; Irbid., 623.Ibid., 791.Ibid., 100. Ibid., 623. Ibid., 189PHYSIOLOGICAL CHEMISTRY. 189year-Henri and Mayer,l who show that the emanations alterthe osmotic properties of blood corpuscles and change haemo-globin into methaemoglobin ; Bonchard, Curie, and Balthazard? whohave demonstrated the fatal effects of air charged with the emana-tions in mice and guinea-pigs; after death the tissues, especially ofthe surface, are radioactive. Salomonsen and Dreyer killedanimalcules by exposure to the emanations. A. B. Green4 per-formed similar experiments with vegetable micro-organisms, andthese also after exposure show marked signs of radioactivity.We may next select a couple of examples from agents which havebeen known longer, and which still continue to excite controversy,namely, alcohol and chloroform.That alcohol is a food within certain limits may now be acceptedas a proved fact, whatever view may be taken as%o the advisabilityof its habitual use.This has been shown by Atwater in America,and by Rosemann in Germany, the last of whose painstaking re-searches has recently been p~blished.~ Another controversial pointfrequently cropping up in connection with alcohol is whether or notit is in small amount found in normal animal tissues. Landsberg6supports the view that i t is. The proportion in which it occurs isstated to be from 1 in 11,000 to 1 in 33,000 parts. The source ofthe alcohol is uncertain; unless bacterial action occurs, it is not in-creased by digesting the tissues with sugar.I n reference to chloroform, one may allude to the important dis-cussion opened by Sir Victor Horsley a t the Oxford meeting of theBritish Medical Association, in which the majority of the leadingphysiologists and anmthetists of the country took part.’ Althoughthe speakers differed as to the best form of apparatus to use, VernonHarcourt’s and Dubois’s being those most discussed, i t is satisfactoryto find that all agreed that 2 per cent.of chloroform vapour in theair is all that is necessary, and that beyond this proportion dangerlies. Dr. Waller, who has been specially instrumental in forcingthis conclusion on anesthetists, has introduced a simple densimetricmethod of estimating chloroform.8 Perhaps the most interestingcontribution to the chloroform question from the chemical point ofview is that by Moore and R ~ a f .~ They point out that all livingcells are subject t o anaesthesia, although, of course, most attention isgenerally directed to the units of the nervous system. The actionmust, therefore, take place between the anzesthetic and somechemical substance present in all varieties of protoplasm, andtheories based on the high content of narve-cells in lecithin andfatty constituents may be disregarded. Proteid is the material ofAbstr., 1904, ii, 184. Jbid., 502. Ibid., 577. Ibid., 503.f b i d . , 187.AM., 499. Ibbid., 756. Ibid., 622. lbid., 501.See also Goddard, ibid., 827, for similar experiments 011 dogs190 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.all others universally present, and it is found that chloroform formsloose compounds with many proteids; if in excess, i t will precipitatesome of them.This explains the greater solubility of chloroformin blood, o r serum, o r hzmoglobin solutions, than in water or insaline solutions. The loose compound of proteid-chloroform is com-pared to oxyhzemoglobin. When anzsthesia occurs the proteid-chloroform compound of the blood has parted with its chloroform tothe cell-proteids. The compound there formed undergoes dissocia-tion when the chloroform pressure is reduced on cessation ofadministration of the anaesthetic, and anaesthesia thus ceases.The substance of all others which has produced the largestnumber of pharmacological papers has been adrenaline.The workhas not been wholly pharmacological, but much has been done fromthe purely chemical side also. It is not remarkable that adrenaline(epinephrine) should have excited all this interest, for it is one of themost powerful physiological agents that are known. The smalldoses of the homeopathists are gigantic as compared to those ofadrenaline, which are capable of producing distinct physiologicalresults.I will take the work relating to physiological action first.Loeper 1 finds that adrenaline produces haemolysis and stimulates theblood-producing organs; Doyen and Kareff that i t leads to diminu-tion of the glycogen of the liver, and increase of the sugar in theblood; Exner 3 that i t lessens absorption, and so, after its adminis-tration, other poisons like strychnine produce death more slowly ;Meltzer that i t causes the pupil to dilate in the frog in allcircumstances, but in the mammal only after section of the cervicalsympathetic nerve.Hamburger 5 has studied the antagonism onblood pressure between it and " peptone " injected intravenously.The question has been discussed by Embden and von Furth,6 byWeiss and H a r r i ~ , ~ and by others, as to what becomes of it afterinjection. The view has been advanced that it is destroyed in themuscles; Embden and von Fiirth consider that it is destroyed in theblood, but this is not confirmed by Weiss and Harris, who find thatthe blood of an animal poisoned with the drug, but which has be-come '' accustomed '' to the effect, is still capable of producing a riseof blood pressure when injected into another animal. Brodie andDixon * have conclusively proved that adrenaline acts on sympa-thetic nerveendings, not on the muscular fibres where these ter-minate. This idea has been developed by T. R. E l l i ~ t t , ~ whopostulates the necessity for the presence of adrenaline inany effective sympathetic action, and has shown that it1 Absts.., 1904, ii, 196. Ibid., 272. 3 Ibid, 276. Ibid., 560, 632.Ibid., 501. 13 Ibid. 61. Ibid., 628. Ibid. 66, 196.9 Ibid., 577PHYSIOLOGICAL CIIEMISTRY. 191is produced also in the sympathetic ganglia; all embryologistsknow the close developmental association between the medullaof the suprarenal gland and the sympathetic nervous system.The same author has also worked out the action of adren-aline on the b1adder.l Important as most of these conclusionsare, they pale in interest when one comes to the chemical side ofthe investigation. For, not only has the empirical formula ofadrenaline been made out, but also its constitution has been deter-mined. The actual synthesis of adrenaline has not yet been accom-plished, but this culmination of the work cannot be far off, foralready a ketonic derivative (adrenalone) has been synthesised, butits power to elevate arterial pressure is much inferior t o that ofadrenaline. Abel in America and von Fiirth in Strassburg havelong been struggling with this question, and it is curious thatneither of them has the credit of tlhe final discovery, although it wastheir work which paved the way t o it. The priority of the synthesisof adrenalone is now being disputed between Friedliinder andStolz.3The formula for adrenaline is one of two originally suggested byPauly4 and confirmed by J ~ w e t t . ~ Other papers which haveappcared on the question are those by Abderhalden and Bergell,6and by Bertmnd.’The formula in question isoIrand adrenaline is thus a rnethylamino-derivative of catechol.I n the introduction to this article I have drawn attention to thcgreater exactitude which is characterising the work of modernphysiological chemists, and it is most fitting to conclude the reviewby a brief description of this marked instance of useful results fol-lowing a combination of study of a subject from both the physio-logical and the chemical points of view.W. D. HALLIBURTON.Abstr., 1904, ii, 832.See Hans Meyer, Centralblatt. €hy.siol., 1904, 18, 501 ; Abstr., 1904, i, 1069.Absti.., 1904, i, 128, 540.!I Bcitr. eh,em. Physiol. Path.., 1904, 6, 92,Tmns., 1904, 85. 192

ISSN:0365-6217    

DOI:10.1039/AR9040100169

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

AGRICULTURAL CHEMISTRY AND VEGETABLEPHYSIOLOGY.ALTHOUGH Agriculture is the oldest of the arts, yet the applicationof chemistry and allied sciences to it is of but comparatively recentgrowth. It is only natural, therefore, that inquiry should have beendirected in the past .mainly to the explanation of facts and pro-cesses observed in the practice of agriculture rather than to anysubversion of the methods employed in an industry of suchantiquity. But the progress of recent inquiry would seem to beaiming at some revolution in the methods of practice also, and therecord for the year 1904 bears evidence of this.A t the same time, it can hardly be said that the year has beenmarked by any startling discovery, by any epoch-making contribu-tion to our knowledge, or by many events of exceptional interest.Under the last head may, however, be mentioned the issue of theReport of the fifth Internationaler Kongress fur angewandteChemie,” held in Berlin, June 2nd--8th, 1903, vol.111. of thisreport including the Proceedings of Section VII. (AgriculturalChemistry).The year’s Obituary is, happily, a short one, the loss, how-ever, of Dr. A. P. Aitken-who died on April 17th-claimingattention and calling forth expression of regret. For the long termof twenty-seven years Dr. Aitken had occupied the position ofchemist to the Highland and Agricultural Society of Scotland, andwas well known in this connection and its a professional chemist inEdinburgh. He was a frequent contributor, on chemico-agricul-tural subjects, to the Highland Society’s Journal, and was Directorof their Agricultural Station.The outstanding features of the year may be briefly summarisedas follows :-In so far as discovery ” may be spoken of, one mayrecord (1) the application of cyanamide to agricultural purposes,and (2) the improvement and adaptation of “nitragin,” or similarnitrogen-inoculating materials, may be recorded.As regards thelines upon which inquiry has mainly proceeded in differentcountries, i t may be said generally that, alike in England, Germany,and America, attention has been chiefly directed to questions conAGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 193cerning nitrification and the utilisation of atmospheric nitrogen,while, in England and America chiefly, workers have been alsolargely occupied with problems bearing upon the mechanical divisionand physical condition of soils in relation to their agricultural value.Further, the consideration of the ‘( available ” constituents of soilsand of the best means of determining these has engaged muchthought in all three countries.I n Germany, in particular, thebehaviour of farmyard manure, either in respect of the losses itundergoes in making and storage, or of the changes effected inpresence of nitrates applied along with it, has been the subject ofcontinued study. Coming to individual soil-constituents, numerouspoints connected with the existence of an insufficiency of lime andits suitable supply, as also of the inter-relations of lime and mag-nesia as found in soils, and the bearings of these on practice, haveprovided a fruitful field of labour.Green-manuring, in its relationto the “atmmpheric nitrogen” theory, has been pursued both atRothamsted and a t Woburn, and a new branch of inquiry has beenopened up in the study of the influence of minute applications ofsome of the less abundant materials met with in agriculture, suchas manganese. Work in this branch was commenced a t Woburn in1898, and has been continued since, the record for 1904 comprisingthe results of observations not only from this station, but fromGermany and also from Japan.I n the domain of Vegetable Physiology, more particularly, theprominent feature has been the great amount of work done, andthe advance in our knowledge of the enzymes and of their action.Towards this, much service has been rendered in particular by theable contributions of Prof.Vines, Dr. Horace Brown, and Dr. E. F.Armstrong.The appearance in 1904 of the first part of the Transactions ofthe Guinness Research Laboratory1 (under the direction of Dr.Horace Brown) has been, indeed, welcomed ils the first of a seriesof systematic investigations into the nature of barley and thechanges which it undergoes in the germinative process. Prof.Vines’s discourse before the Linnean Society, on Proteid Digestionin Animals and Plants!,” also did much to put on a clear basis theresults of past investigations on this subject.Coming to more strictly agricultural matters, mention should bemade of the papers contributed to the Chemical Society of Londonby Mr.A. D. Hall, director of the Rothamsted ExperimentalStation, on “Mechanical Analysis of soil^,"^ and by Mr. S. F.Ashby on (‘ The Comparative Nitrifying Power of Soils ”; 4 and ofTrans. Guinness Research Lab., 1903.Trans., 1904, 85, 950.2 Linnean Soc., published minutes, December 1, 1904.* Ibid., 1158.VOL. I. 194 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the contributions to the ‘‘ International Congress ” by Prof. A.Frank, “ Die Nutzbarmachung des freien Stickstoffes der Luft furLandwirthschaft,” and Dr. L. Hiltner, “ Die Impfung der Legum-inosen mit Reinkulturen.”A pleasing feature of the year has been the renewal of activityin connection with the “ Rothamsted Experiments,” made famousby the works of Lawes and Gilbert, and with this has come, underthe care of the new director, Mr.A. D. Hall, a welcome popularisingof the work of the station with a view to making it better knownto, and its lessons better understood by, the practical farmer.Already, in 1903 and 1904, have appeared in the Journal of theRoyal Agricultural Society of England, papers dealing with the con-tinuous experiments on mangels3 and on permanent grass,4 andothers are in process of preparation. Further, while the historicallabours of Lawes and Gilbert have been maintained in their in-tegrity and the continuity of the records been preserved, the scope ofthe work has been extended so as t o embrace inquiries into mattersof more recent moment, and others bearing in some respects moredirectly upon farm practice.G y cc YL a rn i d e.To deal now in more detail with the principal points comprised inthe year’s work, we take first the production of cyanamide and itsapplication t o agricultural purposes as a means of utilising thenitrogen of the atmosphere a.nd converting i t into plant food.Frank, of Charlottenburg, gives in the paper to which referencehas just been made, and which was read a t the InternationalCongress in Berlin, an account of his work on this subject, describ-ing how, in conjunction with Caro, he had observed the taking upof nitrogen by the carbides of the alkalis and alkaline earthsformed in the electric furnace.They experimented with the car-bides of barium and calcium in particular, the latter being foundthe most applicable, inasmuch as the taking up of nitrogen bycalcium carbide produced, not calcium cyanide, but a separation ofcarbon and formation of calcium cyanamide (CaC, + 2N =CaCN, + C).From this compound, by the interaction of water, ammoniawould be formed (CaCN, + 3H,O = CaCO, + 2NH3). This substance couldalso be produced by heating lime or chalk with charcoal a t 2000O ina current of air. The product calcium cyanamide is sold in Germanycommercially under the name ‘‘ Kalkstickstoff,” and contains from14 to 22 per cent. of nitrogen, according t o its varied method of pre-Ber. V. Tnter-. Kongr-esr fiir nngewandte Chemie, Berlin, 1903, 3, 727.Ibid., 799.B i d . , 1903, 64, 76.J.EOZJ. Agyic. SOC., 1902, 63, 27AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 195paration. It remained to put it to the test for agricultural purposes,and this was done by Wagner at Darmstadt and Gerlach at Posen,both by pot-culture trials and in the field, and with results that be-tokened success, it being stated that the effect of the cyanamide fellvery little short of that produced by salts of ammonia containingthe like quantity of nitrogen. The nitrogen of the calcium cyan-a,mide is changed into ammonia in the soil, and this then undergoesnitrification. Although these favourable accounts of its use havebeen set out, i t is evident that the material must be put morethoroughly to the test before a definite pronouncement can be made.I n 1904, a field trial with it was undertaken a.t Rothamsted, incomparison with ammonium sulphate, but without any very definiteresult. I n Germany, the field trials were never as successful asthose with pot-culture, and there was evidence that with some soils,especially those of peaty nature, there was an injurious action.This is attributed to the formation of dicyanodiamide by the actionof acids.Takke 1 states that a poisonous action was observed whenthe material was added just before sowing the seed, but not whenan interval of two and a half months was allowed to elapse. It isevident, however, that, even if proved useful agriculturally, thesuccess of cyanamide as a commercial enterprise must dependentirely upon the cheap production of electric energy, as wherewater-power is available.Ni t ag in.Nitragin was originally brought out by Nobbe, of Tharand, andHiltner in 1896, but, as is well known, it failed in its original form.Since then efforts have been made to reproduce i t in better form, i tbeing felt that the underlying principle in its preparation and usewas correct and consistent with the discoveries made by Hellriepl.It was believed that the failure of the “nitragin,” as a t first pro-duced, was due to the bacteria dying for want of suitable foodbefore the seed germinated, or, possibly, to the bacteria beinginjured by secretions from the seed itself in its early stages of ger-mination.These defects Hiltner (now of Munich) and Stormer havesought to remedy by supplying nourishment for the bacteria in theform of grape sugar and peptones added to the water used for theinoculation and cultivating them in thisS2 Still better than water,they recommended the use of milk.They have made many trialsof the nitragin thus prepared, and on different soils, and theymaintain that a large measure of success has been obtained, theexperiments giving about 78 per cent. of successeS with serradella,75 per cent. with red clover, and 57 per cent. with lupins. Inocula-1 Bied. Cenlr., 1904, 33? 583 ; from Mitt. Ver. Ford. Moorkullwr, 1903, 23, 347.f Ber. V. Inter. Kongress f u r nngewandte Chernie, Berlin, 1903, 3, 799.0 196 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.tion of soil, Hiltner points out, is only suitable in the case of peatland.Still more recently, G.Moore,l of the Plant Physiology Labora-tory, U.S. Department of Agriculture, has introduced anothermethod of preparing nitragin. He holds that the failure inNobbe’s case was owing to the medium used for conveying the bac-teria being too rich in nitrogen, and so he aimed at giving themonly just nitrogen enough. His next step was t o secure a simplemeans of distribution, and, after showing by experiments that thebacteria grown on nitrogen-free media retained their activity fora long time if carefully dried out and subsequently revived in aliquid medium, he used an absorbent, such as cotton, in whichform he distributed the material for use, sending it out in packetsconsisting of the cotton with its dried germs. Along with this gotwo other packets, comprising the food by which the farmer is tomultiply the germs.The first packet contains granulated sugar,potassium phosphate, and magnesium sulphake, and the secondammonium phosphate. The contents of the first packet are dis-solved in water, the dried germs (on cotton) added, and the wholeleft for twenty-four hours in a warm place. The ammonium phos-phate is then added, and the mixture again left for twenty-fourhours, after which it is ready for moistening the seed and thus in-oculating it. Soil may be similarly inoculated. Statements aregiven of promising results obtained from the treatment, but i t isevident that both this preparation and the new one of Hiltner’s willhave to be very carefully and thoroughly tested in this countrybefore one can be assured of their practical application.Znfluence of Nitrates in the Soil o n the Action of Nodtile Bacteria.experimented with T’icia villosa grown inpots with sand and garden soil, and found that when the pots wereinoculated with a pure culture of the I-icia nodule bacteria, ifsodium nitrate (0.5 gram and 1 gram respectively per pot) wasadded, the effect of inoculation was distinctly diminished.Nobbe and RichterXi t r if i c a t i o 1%.Boullanger and Massol carried out experiments on the action ofthe nitrous and nitric organisms on ammonium sdts.They foundthat with the nitrous organism in presence of ammonium sulphatethere was a period of about six days during which n] nitrificationCentury Magazine October, 1904, 68, 835.Ann.In&. Pnsteur, 1904, 18, 181.a Laizdw. Versuchs-Stat., 1903, 59, 167AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 197proceeded; with the nitric organism this lasted only two days.Further, that ammonium salts hindered *the multiplication of thenitric organism, but did not, unless present in considerable amount,retard the functions of nitric organisms already existing.Fausto Sestinil finds that the production of nitrous acid in thesoil does not arise, as has been stated, from the action of bacteria onatmospheric nitrogen, nor, as believed by Bonnema, is it due tothe oxidation of the atmospheric nitrogen by ferric oxide in the soil,but to the presence of the traces of ammonia in the air, which thenbecome oxidised, forming food for the nitric bacteria.S.F. Ashby2 has devised a method for the estimation of thenitrifying power of different soils, with the object of comparingtheir activity in this respect, and thus obtaining a measure oftheir fertility. This work was carried out in connection with theItothamsted experiments, and the soils with which the trials weremade were those the history of which is well known. Afterattempting in vain to inoculate sterilised solutions in the field withsmall quantities of fresh soil taken, with a sterilised spatula, fromthe sides of a hole, and also by the employment of aqueous extractsof soil, Ashby used hollow brass cylinders, fitting loosely into glasstubes, stoppered with an india-rubber disc.These tubes were pre-viously sterilised. A hole was dug in the soil, and one of the brasscylinders inserted at a depth of 10 cm. from the surface, and drivenhorizontally into the soil, after which the core of soil withdrawnwas transferred to one of the sterilised glass tubes. This was takento the laboratory, and, after breaking up, was place$ over sulphuricacid under a bell jar, which was then partially exhausted. Thedrying lasted for 48 hours, the soil was next sieved and well mixed,0.2 gram of it being then seeded into a sterilised solution andincubated a t 29-30°. The culture solution was that employed byWiley : potassium dihydrogen phosphate, 1 gram ; magnesiumsulphate, 0.5 gram ; ammonium sulphate, 0.2 gram; calcium chloride,trace; distilled water, 1 litre.It was found that nitrate formationproceeded well, and there was no evidence of loss from denitrifica-tion. Duplicates from different holes on the same plot were foundto agree well, and the results as regards the relative nitrifyingpower were in accordance with what might have been expectedfrom the history of the treatment of the various plots tried, andfrom a consideration of their crop production. Attempts t o shortenthe period of incubation by the use of stronger culture solutionsresulted in loss of ammonia. Difficulty was experienced in express-ing the “nitrifying power’’ in absolute values, or in terms of somuch nitrogen nitrified per litre per day, Ashby finding thatduring the first fortnight of incubation (the whole period wasL’Orosi, 1904, 27, 1.a 3’.I*aizs., 1904, 85, 1158198 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.30-37 days) no trace of nitrite or nitrate was obtained; when,however, the process was once started, it went rapidly, and in a30 days’ incubation it was during the last two days that nitrifica-tion really occurred. Ashby proposes t o consider the percentage of“total nitrogen nitrified” during an equal period as giving thebest comparison of ‘‘ nitrifying power.”E. J. Russell (an account of whose work has not as yet beenpublished) has devised a method for finding the total ‘(bacterialaction ” of a soil, and for using this as an index of soil fertility.His plan is to ascertain the rate a t which oxygen is absorbed, andhe has applied this to various samples of soils from Rothamstedand Woburn, as well as from Wye College, Kent.The method isto put the soil in a flask provided with a side bulb containingcaustic potash and a delivery tube leading into mercury, and soserving as a gauge. The flask is put into a bath a t 16-18’.As oxygen is absorbed, the carbon dioxide produced is taken upby the caustic potash and the mercury rises in the gauge,giving thus the rate of oxidation, and, presumably, the measure ofthe total aerobic bacterial activity, which is, no doubt, closelyrelated t o the fertility of the soil. The methoqd, as applied to thesoil of different plots and fields of the Woburn Experimental Farm,certainly succeeded in placing them in the order of their respectivefertility, and Dr.Russell states that this has been the case else-where. This method undoubtedly holds out much hope of beingpractically useful.D e nit r ificat ion.Gaspare Ampola and Celso Ulpiani 1 have continued their cul-tivation experiments on this subject; these confirm previous observ-ations, and the authors conclude that calcium nitrate, formed asthe natural product of nitrification, is, in ordinary circum-stances, but slightly attacked by denitrifying bacteria. But, inorder t o avoid loss of aitrogen, fresh stable manure with muchstraw should not be applied to the ground during the period ofactive nitrification; moreover, sodium nitrate, to be used to bestadvantage, should be applied when the stable manure is thoroughlybroken down.This, it may be observed, is fully in accord with theexperience of farming practice.G~eenrnanzcring.The practical application of the principles inculcated by theresearches of Hellriegel has, in England a t least, not met with thesuccess that might have been expected of them. If it be the casethat leguminous crops have the power of utilising the nitrogen ofGuzzettu, 1903, 33, 125-129AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 199the atmosphere, then it would seen1 an easy icatter to enrich soils inrespect of nitrogen by the growing of leguminous crops on them.So far, however, as this has been tried, the results are not inaccordance with theory. A t Woburn, where this point has beentried continuously since 1892,l no benefit has resulted to the suc-ceeding corn crop from the growing and ploughing-in (green) of aleguminous crop, such as tares (vetches), as compared with that ofa non-leguminous one such as mustard.The mustard crop has eachtime produced a better corn crop following its growth and plough-ing-in than have the tares, and this whether the green crops hadno manuring or were supplied with mineral manures in the form ofsuperphosphate and kainit. It was found, moreover, that the taressupplied to the soil considerably larger amounts both of organicmatter and of nitrogen than did the mustard, but there was no cor-responding increase in the corn crop, either with wheat or barley.I n 1904, lest it might be said that the accumulated nitrogen hadnot had time to become available, a spring crop (barley) was takenafter the wheat crop of the year previous, but even with this therewas no better result from the tares than from the mustard.Theremay be conditions militating against this experiment turning outin accordance with what one would expect from theoretical con-siderations, and the matter is under further investigation, but a tpresent, a t all events, theory does not appear to be borne out inpractice, at least so far as the tares crop is concerned. A seriesof experiments bearing on this same subject was instituted in 1904a t Rothamsted, where also the influence of different clovers isbeing further investigated in continuation of the researches ofLawes and Gilbert. It is well, however, to point out that untilthe teachings of theory can be shown in practical application underthe ordinary conditions of farming, there can be little hope of theirsuccessful incorporation in our agricultural system.Incidentally,too, light is thrown on the need of supplementing pot-cultureexperiments by others on a field scale.,So i Z cc n d Soi Z-co izst i t u e n t s.As noted previously, a great deal of attention has been directed,and very rightly so, to the consideration of soils in regard to theirphysical condition and state of mechanical division. I n AmericaWhitney and Cameron, and in England A. D. Hall, in particular,have been very active. The American school, however, as repre-sented by Whitney and Cameron,2 have gone so far as to declaref3 U.S.Dept. of Agric., Bicrenic of Soils, No. 22, (‘l’lie Chemistry of the Soil asJ. Roy. Ayric. Soe., 1903, 64, 335.related t o Crop Pioduction.” By M. Whitiiey and F. K. Cameron200 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.that the chemical analysis of a soil has little to do with or to tellabout the fertility of a soil, and that fertilisers, if they have anyeffect in increasing a crop, do so mainly by reason of their alteringthe physical texture of the soil, o r by stimulating the root rangeof the plant. Whitney and Cameron express themselves dissatisfiedwith the want of any correspondence between crop production andthe results of soil analysis as obtained by the action on the soil ofeither weak or strong acids, and they take instead the aqueous solu-tion obtained by shaking up 100 grams of soil with 8 litre ofwater, then allowing this to stand for twenty minutes.This solu-tion is examined by various colorimetric methods for getting rapidlyquantitative estimations. As the outcome of this procedure, which,it must be pointed out, has no correspondence whatever with whattakes place naturally in the soil, they came t o the conclusion “that,with occasional exceptions, the composition of the soil solution andthe concentration is about the same in all cultivable soils.’’ Theyconclude, therefore, that all soils are amply supplied with the neces-sary mineral plant foods, these not being in themselves of im-portance except so far as concerns the supply of soil moisture.Sucha position as that taken up by Dr. Whitney and his colleague must,indeed, be startling to any student of agricultural chemistry in thiscountry who has had before him the long-continued experiments atRothamsted and elsewhere, and Mr. A. D. Hall1 was not slow t oshow the utter untenableness of the views enunciated. He pointedout that the theory could be disproved, even from the figures quotedby the authors, both as regards the formation of nitrates in the soiland the phosphoric acid contents, quoting also instances from theRotharnsted experiments in support of his argument. As Mr. Hallsays, whatever may be the case in America, where much of the landis new and has only recently been brought under cultivation neces-sitating the use of fertilisers, Dr.Whitney, although right in hismain contention as to the water content and temperature of soilsbeing main factors in crop production, has been too ready to ignorethe vast body of knowledge accumulated in this country concerningthe requirements of particular crops for particular fertilising in-gredients, and hence has been led to attribute no importance t o thechemical composition of the soil, which, nevertheless, still remainsa large factor.Soluble Salts in Soil.Other investigators in America, and notably Kingj2 have beenworking at the distribution of soluble salts in soils in their relationto the solid and gaseous components of the soil, and as supplyingATature, 1903, 69, 58, “A New Theory of tlie Soil.”W i s , Agric.Exper. Stat. Bepork, ‘‘ Soluble Salts of Cultivated Soils.AGRICUJ,TURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 201nutriment to the plant.also in regard to alkaline soils, and Hilgardseveral years’ work on this subjectA number of papers have been writtenhas summarised hisSoil A cidit y.On the other hand, soil acidity has claimed considerable attentionboth in America and in England. F. P. Veitch2 has made a com-parison of the different methods of estimating soil acidity, and thelimewater method introduced by him is recommended. I n Englandthe question of soil acidity has derived considerable importancefrom the exceptional results found a t the Woburn ExperimentalFarm3 as the outcome of growing continuously wheat and barleycrops on the same land-a light sandy loam, poor in lime-andmanuring these year by year with ammonium salts (ammoniumsulphate and chloride).The continued use of these salts hasbrought about absolute failure of the crop and the productionof an acid condition of the soil, the nature of which is now underinvestigation. This acid condition, it is found, is remedied by theapplication of lime to the land, and healthy crops are again pro-duced. The acidity itself is removed by continued washing withwater, and also to some extent by exposure to air alone. Followingon this, investigations are in progress at Woburn in reference to therelative action of water and of solutions of ammonium sulphate,ammonium chloride, and sodium nitrate on the soil, and to the rateof removal of organic matter, lime, and other constituents there-from. These shqw, so far, that the removal of lime proceeds morerapidly with all the above salts than with water, that it is morerapid with ammonium chloride than with ammonium sulphate, andthat both these salts take out the lime nearly twice as quickly asdoes sodium nitrate.Wide by side with these results have beenobtained interesting ones regarding the mechanical action of theabove salts on the soil, t o which reference will be made later.A uaila b ility of Soil-constituent s.The question of the availability of soil-constituents and the bestmethods of ascertaining this continues t o be a prominent one, andin England, Germany, and America alike many investigations havebeen made. Emmerling? summarising his experience of differentmethods, recommends for the determination of phosphoric acid aCulifornia Agric.Eqer. Stat., Bulletin No. 128, “ Nature, Value, and Utilis-ation of Alkali Lands.”J. Anw. Chent. SOC., 1904, 26, 637.J. Eoy. Agric. SOC., 1903, 64, 355.Bey. 7, Inter. Kongress fur ungetunitdte Chemic, 1903, 3, i 3 3 202 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.2 per cent. solution of citric acid, and for lime Kellner’s suggestionof boiling in a concentrated solution of sal-ammoniac.has shown that after extracting a soil for seven days with a 1 percent. solution of citric acid, it is rendered much less fertile, especiallyat first; but that gradually, during the growth of the plants,chemical changes in the soil render it capable of again supplyingplant food.He hence holds that while B. Dyer’s method of deter-mining the “available” plant food in soils is very valuable, it isnecessary to take into consideration also the rate at which thisavailable plant food is capable of being renewed, and he hints thatwhilst this may be much the same for soils under similar climaticconditions, it may vary much when tropical or sub-tropical soils areconsidered.H. IngleAsh of Plants and Analysis of Soils.The difficulties connected with the interpretation of soil analyseshave led to some revival of the old idea of the ash of plants beingthe best guide to the proper manuring of the plant. This has beenworked at by Heinrich, Helmkampf, Atterberg, and others, andA.D. Hall? in a paper read at the British Association at Cam-bridge (1904), reverts to the subject. An examination of dataaccumulated from the Rothamsted experiments shows that withcereal crops, when the whole plant is taken into consideration, thecomposition of the grain fluctuates but little with the manuring,and the range of variations shown by the plant is less than thatindicated by soil analysis. But with root crops, analysis of the ashindicates a much wider range of variation where manuring withphosphoric acid or potash has given distinct response in the crop,and in these cases the analysis of the ash shows promise of affordinga better guide to the requirements of the soil than does the analysisof the soil itself.Mechanicul Analysis of Soil.The mechanical analysis of soils has received further attention inthis country, and in a paper contributed to the Chemical SocietyA.D. Hall has dealt with a number of soils taken from experi-mental plots of different fields at Rothamsted. Adopting Schloesing’smethod of a preliminary treatment of a soil with dilute acid followedby ammonia, he has divided the soil into separate fractions, usingthe method of sedimentation recommended by Osborne, which con-sists in dividing the soil into two fractions by sieving and five bysedimentation from water. Hall found that there was rarely obtainedTram., 1905, 87, 43, “The Available Plant Food in Soils.”Brit. Asscc. Beport, 1904. Sectioii li. Sub-section of Agriculture. “ Aiialysisof the Soil by iiieaiis of the Plant.” Trans., 1904, 85, 950AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 203as much of the finest fraction by the sieving of the raw soil asthere was when the soil was treated preliminarily with acid.Whenvariations were found, these occurred in the case of soils rich inhumus, inasmuch as the humates, which probably acted as a bindingmaterial, were decomposed by the acid treatment. The acid treat-ment has the further advantage of removing all soluble salts whichwould interfere with the sedimentahion. He therefore concludesin favour of the preliminary treatment with acid. Determinationsof alumina, silica, and ferric oxide are given in the various fractionsseparated by the mechanical analysis, and it is shown that, althoughthe alumina increases as the particles become smaller, i t is the sizerather than the chemical composition of the particles that deter-mines what the fractions are.Influence of Soluble Sults on t h e Condition of Soil.A further paper by A.D. H d l , in the same Journa1,l deals withthe effect produced on soil by the continued application to it ofsodium nitrate. Again the Rothamsted plots are brought into use,and an examination of some on which sodium nitrate has been usedfor a long series of years, when compared with others where nonehad been applied, shows that in the former case the finer particlesare washed down into the subsoil. This was most marked in the caseof the mange1 field, where cultivation had gone on continuously,whereas, on the grass plots, where there had been no stirring of thesurface, this loss of the finer particles was not found.Mechanicalanalyses of the subsoils from cultivated land, where sodium nitratehas been used continuously, showed them to be much richer in thefiner particles than where no nitrate had been applied, and Hall con-cludes that this is due, not to any solvent action of the nitrate, butto the " deflocculating " action of this salt and subsequent wash-ing of the finer particles into the subsoil. This receives confirm-ation from experiments already noted a t Woburn, where the rela-tive actions of sodium nitrate and ammonium salts on the soil werecompared (see page 201). On removing the soils from the cylinders(2 feet long) in which they had been subjected to continued wash-ing with solutions of the salts, i t was found that a t the bottom ofthe sodium nitrate cylinder there was a closely aggregated mass ofthe finer particles, the texture of the soil being quite different tothat of the soil in the other cylinders.This mass had, no doubt,been formed in the way indicated by Hall, the finer particles havingbeen carried down to the subsoil.1 TTCWlS., 1904, 85, 964204 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The “Rarer ” Constituents of the Soil.The influence on plant life of those constituents of the soil which,because of their rarer occurrence or presence in but small amount,have been less studied, has recently been brought into some promi-nence both in this country and elsewhere.I n 1896 Mr. E. H. Hills,whose attention had been directed to the earlier work of PrinceSalm-Horstmar, left a bequest for the purpose of carrying on in-quiries on the influence of the “ rarer forms of ash ” on plants, andout of this the Woburn Pot-culture Station mas founded. Sinceits opening, in 1898, experiments in the direction indicated havebeen carried on, and have been reported in successive issues of theJournal of the Royal Agricultural Society of England. The lastpublished account deals with the action of the iodides and oxidesof manganese, potassium, sodium, and lithium on wheat andbarley. The iodides generally have proved harmful, even whenapplied at the rate of 1 cwt. per acre, but the oxides have in eachcase been beneficial.Lithium salts have had a retarding effect a tfirst upon germination, and the oxide further produced amechanical change in the soil, causing i t to “cake.” Water-culture experiments carried on at the same time with barley showeddistinct differences in the nature of the root produced with theiodides and oxides respectively, that with iodides being thin and deli-cate, with one long tap root and but few side shoots, whereas withthe oxides there was formation of a short, thick tap root andabundant rootlets and fine hairs.have dealt withthe influence of other “ rarer ” constituents, such as fluorine,chlorine, bromine, and titanium, in addition to iodine, manganese,and lithium mentioned above, and among other methods tried wasthat of soaking the seed, before sowing, in solutions of salts contain-ing these substances.This preliminary soaking of the seed, wherebybut small quantities of the constituents are taken up, seems topromise results of much interest, and the work is now being carriedon further. Indeed, this would appear t o be the line which futurestudy should take with these “rarer forms of ash,” namely, theinfluence of minute quantities of them rather than the applicationof manurial dressings. Meantime, this work has claimed attentionin other countries. 0. Loew3 found that small amounts of man-ganese sulpliate gave an increased yield in the case of differentJ. Boy. Agric. Soc., 1904, 65, 306.J. Boy. Agric. Xoc., 1900, 61, 567; 1901, 62, 317; 1902, 63, 346; 1903,Previous experiments a t the Woburn Station64, 345.a U i c d .Ccnti.., 1904, 33, 91 j from Landlo. Jnhrb., 1903, 32, 437AGKICULTURAL CHEMISTRY AND VEGETAHLE PHYSIOLOGY 205families of cultivated plants, cruciferous plants, in particular, beingmore benefited than the Grnm-Mzecz. Experiments with rice gavenot only increased yield of corn, but more grain t o straw as theresult of using manganese salts. Sodium fluoride and potassiumiodide, similarly used in small doses, increased the yield of oats andpeas, as did also uranyl nitrate. Loew subsequently went to Japan,and there continued his investigations,’ trying, among other things,the effect of manganese sulphate on trees; Cryptonzeriu japonica hefound to be doubled in weight in eighteen months.Sodium chloride,o n the other hand, reduced the growth. Other workers at Tiskyahave carried on investigations in the same line. K. As6 foundan increase of one-third in rice production from an application ofmanganese chloride. Y. Fukutome3 showed that the joint appli-cation of iron and manganese affected the yield of flax favourably,and M. Nakamura * similarly experimented with zinc sulphate,nickel sulphate, and cobalt nitrate in small quantities on AZZium,Brussica Chinensis, and barley, noticing slightly stimulating effectsin most cases,*althougli nickel and zinc proved hurtful to barley.Gabriel Bertrand,s of Paris, in a paper read before the Inter-national Congress at Berlin, 1903, speaks of the necessity of con-sidering other constituents of the soil than those which one usuallytakes into account, and refers to his own published work on thepart which manganese plays in the action of the oxydases.Lateron in the discussion he referred to the work of As6, quoted above,and to the latter’s observation that applications of manganese salts,while a t first favourable to vegetation, might become hurtful aftera certain proportion was reached.Organic Matter in Soil.F. I<. Cameron and J. 3’. Breazeale,6 after comparing differentmethods for the determination of organic matter in soils, give pre-ference to that of oxidation by means of chromic acid, using 10grams of soil with 5-10 grams of potassium dichromate, and thenconcentrated sulphuric acid added gradually. The organic matter istaken as being the weight of CO, x 0.471.Slight modifications arerequired in presence of chlorides or carbonates.BdE. Coll. Agr. Takyci, 1904, 6, 126.Ber. 7. Inter. Ko?&g.gress far angewandte Chenaie, Berlin, 1903, 3, 839, ‘‘ LesIbid., 131.8 16id., 136. Ibid., 147.Engrais compl4mentaires. ”6 J, Amer. Chenz. SOC., 190.1, 26, 29206 ANKUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Fertilisers and their Influence.Farmyard and Organic Manures.The making and storing of farmyard manure continues to exer-cise a great deal of interest among scientific inquirers in Germany.The work on this subject is very well summarised by W. Somerville 1in his address at the British Association meeting, Cambridge, 1904,and Schneidewind,2 of Halle, dealt also with i t in a paper readat the International Congress in Berlin, 1903.Schneidewind, afterdiscussing the various methods suggested for conserving thenitrogen in farmyard manure, shows that they one and all havedrawbacks attaching to their use, and comes to the conclusion-already well established by experimental inquiry and practical ex-perience in England-that there is no plan so good as that ofmaking the dung in deep pits, or boxes, with t.he use of litter (inGermany usually peat-moss with loamy earth thrown over), thestock treading the manure down and so keeping it moist and firmlyconsolidated, it being then left to accumulate until ready forremoval.The increasing supply of residues rich in potassium salts, fromdistilleries where molasses and similar substances are used, hasled to these being incorporated with peat to form a “humo-potassic ”m a n ~ r e , ~ or these alkali salts may be used in conjunction with peat,previously rendered alkaline, and insoluble phosphates in order toform a humo-phosphatic manure.Organic substances are believed to exert a solvent action onminerals ; this view has received confirmation from experiments byA.Stal~triirn,~ who thinks that the action is dependent on biologicalactivity. Thus he finds that while sterile organic substances haveno solvent action whatever on tricalcium phosphate, yet when thefermentation set up (according to the nature of the organic sub-stance) is of the lactic or butyric kind (as with milk, milk-sugar, orpeat with milk-sugar) there is a marked action, but when an am-monia o r carbon dioxide fermentation is produced (as with peat,dung, &c.) it is much less marked.The influence of lime on the other constituents of the soil, andthe importance of having a sufficiency of it present in a soil, haveBrit.Assoc. Report, 1904, 12.Ber. T. Intel’. Kongress fiir angewandte Chemie, Berlin, 1903, 3, 794, “DieFr. Pat., August, 1903, 338, 981.Sub-section K.Rehandlnng nnd Wirkung des S talldiingers. ” * Centr. Bakt. Par., 1904, 11, 724AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 205’always been recognised alike in practical agriculture and in agricul-tural science.The increasing cost of lime has, however, conduced much t o theneglect of the good old practice of liming land, and this has in-cidentally brought out some very valuable points regarding theeffect of the continued use of ammonium salts on soils naturallypoor in lime. Of these the soil of the Woburn Experimental Farmfurnishes a typical example, being a light sandy loam, on thelower greensand formation, and containing about 0.25 per cent.oflime (CaO). For twenty-seven years pIots on which wheat andbarley, respectively, have been grown year after year, have beendressed each season with ammonium salts (ammonium sulphate andchloride), either aIone or in conjunction with mineral manures(superphosphate and sulphates of potassium, sodium, and mag-nesium). For the first twenty years there was no failure of crop,but after tliat time there began a decline, more rapid with barleythan with wheat, and ultimately entire sterility of the land and anacid condition of the soil were produced (see page 201).This wascorrected a t once by the application of a dressing of lime (twotons per acre), and good crops were again obtained, the influence ofthe lime telling for the next seven years. These experiments haveled to the further investigations noted on page 201 on the rate ofremoval of lime from the soil, and the changes produced by am-moniacal and other salts. The importance of lime as a constituentof agricultural soils was further emphasised by H. Immendorff, ofJena,2 in a paper read a t the International Congress a t Berlin, inwhich he speaks of the influence which lime has in rendering bothnatural and artificial fertilisers effective.He refers further to thepresence in certain moorland soils of a lime-compound, or, rather,group of compounds, which he calls “ humussaure kalk.” Thesesoils, although they contain in the dried state 2 per cent. or more ofcalcium oxide, yet have frequently no trace of calcium carbonate;the presence, however, of these I f lime-humus ” compounds ensuresto the plants abundant lime for many years to come. For the readydetermination of available lime, Immendorff recommends Kellner’smethod of extraction with sal-ammoniac solution.While lime is of such importance, iC has been shown, however,that excess of i t is not desirable, and many experiments have turnedupon the relations of the contents of lime and magnesia which it isdesirable to have in soils.has pointed out, for instance, thatJ. Roy. Agric. Xoc., 1903, 64, 329 and 355.Ber. V. Ircter. Kongress f u r aiagcwandte Chenaie, Berlin, 1303, 3, 736, ( r DieU.X. Uept. Agr. Bur. Plant Ind., Bull. No. 1, “The Relation of Lime andLoewKalkbedurftigkeit der Kulturboden und ihre Bestimmung.”Magnesia to Plant Growth.208 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.there is a definite ratio of lime to magnesia which should exist inthe soil in order to produce the best results with any one p!ant, andthat this ratio differs for different plants, excess of either con-stituent doing harm. A moderate amount of lime is advantageous,but an excess does harm; lime salts counteract the injurious actionof magnesia, and allow the latter to act as a plant food.Loew putsthe best relation of CaO : MgO at about 1 for most cereals, whereaswith other crops, especially the more leafy ones, twice or three timesas much lime is needed.K. As61 found the lime factor for rice to be about 1, but theyield of rice was less diminished by an excess of magnesia than bya similar one of lime.R. Ulbricht? experimenting with vetches on a soil containingonly small amounts of lime and magnesia, found that lime inmoderate amount increased the yield, but reduced it when in excess.Heavy applications of dolomite also were injurious. With p~tatoes,~lime and marl increased the yield of tubers and of dry matter inthe tubers, but increased the yield of leaf more than that of thetubers, In the absence of lime there was least phosphoric acid inthe leaf, but with lime present the amount of potash in the leafwas increased.I n the tubers there was little difference as regardsthe phosphoric acid and potash, ils the result of applying or with-holding lime. As more magnesia was applied the leaves were foundto contain less calcium, but the tubers were not affected in this way.The influence of lime on phosphates used in conjunction with i thas also been studied. H. Bachmann4 found that lime and basicslag used together increased the yield of rye (grain), but not thatof oats (grain), and lime with phosphoric acid increased the beetcrop. B. Schulze’s5 experiments on the influence of lime onbone-meal show that the benefit of the phosphoric acid of thebone-meal varies according to the time of liming, it being least whenthe two are applied together in spring, and greater when the lime isapplied in autumn and the bone-meal in spring, but that bone-mealand lime should not be applied to the same crop. Schulze attributesthe diminution of crop to the action of the lime on the phosphoricacid of the soil, which becomes thereby difficultly soluble.Theorganic acids in the soil are likewise neutralised and their solventaction lost.1 B d l . Coll. Agr. T6ky6, 1904, 6, 97.Landw. Yersuchs-Stat., 1904, 60, 135.Ibid., 1903, 59, 1.Bied. Centr., 1903, 32, 801-803Chenz. Zeit., 1904, 28, 158AGRICULTURAL CHEMlSTRY AKD VEGETABLE PHYSIOLOGY. 209Phosphates.The search for further supplies of phosphatic materials continues,and during 1904 new rock deposits of calcium phosphate have beenfound in Tunis and in South Australia.The former are in thedistrict of Uarfa-Tarf, analysis showing an average of 63 per cent.of calcium phosphate, with 14-20 per cent. of calcium carbonateand 1-5 per cent. of alumina; the latter on Yorke peninsula, whencesamples have given calcium phosphate varying from 70 to 83 percent.Solubility of Phosphates.Several new processes have been introduced for making the phos-phoric acid in raw phosphates soluble for manurial purposes.Among these is one by A. Ystgaard,l in which powdered apatite isfused with carnallite for 10-15 minutes at 700--800°, the followingreaction taking place : -Ca,P,O, + SMgCI, = Mg,P,O, + 3CaC1,.Theproduct, which is easily pulverised, contains 80 per cent. of its phos-phoric acid soluble in a 2 per cent. citric acid solution. A mixtureof 100 parts of apatite, 200 of carnallite, and 100 of kieserite willyield, after lixiviation with cold water, a product with more than20 per cent. of phosphoric acid and 7 per cent. of potash. Experi-ments with this material have shown that it gives better resultsthan basic slag.Nitre which has been washed, or a hot aqueous solution ofsodium bisulphate, has been used to act on calcium phosphate soas to obtain the greater part of the phosphate in a form in which itis soluble in water or in citrate solution. Wolters3 has fused to-gether compounds of silicic acid with neutral or basic compounds ofphosphoric acid, and then suddenly cooled the product.The phos-phates are found to be readily soluble in citric acid. The same maybe produced by mixing natural phosphates with silicates previouslyprepared by the fusion of sand with alkalis. P. Wagner4 hasprepared “ Wolter phosphate ” by fusing together a mixture of 100parts of crushed phosphorite, 70 parts of sodium bisulphate, 20 partsof calcium carbonate, 22 parts of sand, and 6-7 parts of coal. Theproduct is poured into cold water and, after drying, is finely ground.Of the phosphate, 97 per cent. was found to be soluble in citric acidsolution, and in vegetation experiments with oats and peas the newmaterial was not much inferior to superphosphate, and superior tobasic slag.n e s e results were confirmed by W. Schneidewind andTeknish Ugeblad, Christiania, 1904, 50, 329 ; Chem. Zeit., 1904, 28, 56.M. Fournier, Fr. Pat., Jan. 1903, 336, 872.Fr. Pat., Sept. 1903, 335, 509. Bicd. Ccntr., 1904, 33, 301.VOL. I. 210 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.D. Meyer While less phosphoric acid wastaken up from the -Walter phosphate than from superphosphate,more was taken up than from basic slag. The new material canbe kept quite well, and is not hygroscopic.Mineral phosphates .have also been fused in a furnace with lime byW. Mathesius (Berlin), t o form a tetrabasic phosphate of calcium.The product is treated with steam under pressure, or with exhauststeam, in a closed vessel, until i t crumbles to a dry powder.on mustard and oats.Action of Salts o n Phosphates.Salts, such as ammonium salts, which undergo decomposition inthe soil, are termed by J.W. Schulow3 “physiologically acidsalts.” These, he holds, have the power of rendering phosphatesmore available by reason of the action of the acid of the ammoniumsalts upon them. I n pot experiments with barley, better resultswere produced by using a mixture of phosphorite and ammoniumsalts than by using the two substances separately. This result, how-ever, it may be pointed out, is nothing more than was brought outyears before in the Rothamsted experiments and confirmed atWoburn, although the exact explanation of the action may bewanting.F. K. Cameron and L.A. H ~ r s t , ~ working on the action of waterand saline solutions on certain slightly soluble phosphates, statethat the phosphates of iron, aluminium, and calcium are all hydro-lysed by water, and the solutions always contain free phosphoricacid. Whilst the free acid tends to increase the solubility of thephosphate, the base, although in solution in smaller amount, tends todecrease this solubility. Hence potassium chloride added would de-crease the amount of phosphoric acid rendered soluble from phos-phates of iron, aluminium, or calcium. The decomposition of thephosphates, either in water or saline solutions, is accelerated by arise of temperature.Ru perph osphat e .The increasing demand, especially abroad, for superphosphate ina finely divided and dry condition has led to the introduction of pro-cesses for the artificial drying of superphosphate by heat. A.Gr6goire and J.Hendrick experimented on barley with super-phosphate that had been dried at 1 6 5 O , and found that the changesproduced in the superphosphate in no way decreased its manurialvalue.I CJzeni. Cent?.., 1904, ii, 788 ; from Landw. Jalt~b., 1904, 33, 342..Big. Pat., June, 1904, 13,361.J. Amer. Chem. Xoc., 1904, 26, 885.Bied. CeaIr., 1904, 33, 79.Chem. Ceqttr., 1904, ii, 555AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY 21 1Potash Salts.J. Dumont,l in investigating the distribution of potash in differentsoils, found that in one soil, which contained 0-853 per cent. of totalpotash, potash manures were ineffective, whereas with another,which contained 0.894 per cent.of total potash, they acted verybeneficially. A closer examination of the soils, however, showedthat in the first case five-sixths of the potash were contained in thefiner portions of the soil, but, in the other, seven-tenths of thepotash were in the coarse sand. Potash manures, accordingly, maybe expected to do good on granitic soils in which, although theamount of potash may be large, it is passive owing to the povertyof the soil in fine material which will readily give up potash.Experiments have been made by Schneidewind and Ringlebento compare the action of pure potassium salts with that of crudesalts in conjunction with lime. When soil was deficient in calciumcarbonate, potassium chloride and sulphate were both found to dobetter than kainite, but where lime was sufficient, kainite was pre-ferable.The action of sodium in presence of potassium is not tobe attributed solely to its taking the place of potassium, but, pos-sibly, also to the production of sodium nit'rate and phosphate, andto the greater .diffusibility of these salts. The chlorine of thesemanures was. found to be distributed chiefly in the straw of cerealsand in the leaves of root crops.Schneidewind and D. Meyer found that sodium chloride, if usedwith a small amount of potassium, slightly increased the yield ofpotatoes, but when there was it large amount of potassium thesodium chloride considerably decreased the yield. On the otherhand, mangels benefited by the addition in all circumstances.The authors conclude, therefore, that it is better to use the purepotash salts €or potatoes, and kainite or other crude potash saltsfor mangels.It may be pointed out here that the maritime originof the mange1 may have much to do with this result.T. Schloesing, j ~ n . , ~ shows, by comparison of soil in which maizewas grown with the same soil without crop but kept in the samestate of humidity, that plants draw the whole of their potassiumcompounds from the potassium salts dissolved in the water of thesoil, and not by direct action of the roots on the solid substances.Compf. rend., 1904, 138, 215.Landw. Jahrb., 1904, 33, 353 ; Absty., 1904, ii, 769.Chem. Centr., 1904, ii, 788 ; from Lnndw. Jahrb., 1904 33, 347.Compt.rend., 1903, 137, 1206212 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Nitrogenous Salts.Wagner and others found that farmyard manure, when used ongarden soil, either alone or with sodium nitrate, gave rise to loss, fol-lowed by an increase in the total amount of nitrates, whereas in thecase of soil alone, or soil to which sodium nitrate was added, theamount of nitrates remained constant during the whole period ofthe experiment (64 days). When ammonium salts were used withfarmyard manure, a reduction of nitrates occurred for the firsttwelve days only, then came a considerable increase up to 96 days,after which the nitrates again diminished.Further experiments by Wagner, also recorded here, on am-monium salts as compared with sodium nitrate, gave, on theaverage, over a large series of different crops, 43 per cent.of thenitrogen as being utilised by t h e crop when ammonium sulphatewas used, as against 62 per cent. with sodium nitrate.That nitrogenous salts like ammonium sulphate and sodiumnitrate, after being applied for some years, are not devoid of after-effect is shown by the Rothamsted experiments.2 Barley wasgrown without manure for two years (1902-1903) on plots onwhich, for the previous twenty-six years, potatoes, unmanured orvariously manured, had been grown. The yield of barley, even inthe second year, was twice as high on plots where ammonium saltsalone, or sodium nitrate alone, had been previously applied eachyear as it was on the unmanured plot.Considerable attention has been directed, especially in Franceand Belgium, to the occasional occurrence of perchloratea in sodiumnitrate.H. Pellet3 (Paris) read a paper on this subject a t theInternational Congress a t Berlin, 1903, in which he called atten-tion to a report of D. Crispo, director of the Antwerp State Labora-tory, setting out injurious results due to the use of sodium nitratecontaining chlorates and perchlorates. Sodium perchlorate hasbeen found to be more hurtful in its effects than potassium per-chlorate, and potassium chlorate is still less harmful. Pellet dis-cusses methods for estimating the amounts of these salts that maybe present, and concludes that sodium perchlorate, if present even tothe extent of 1 per cent., will be injurious to vegetation, and mustnot be allowed to occur in commercial sodium nitrate.Bied.C'entr., 1903, 32, 728.Rothamsted Experiments, Lawes Agricultural Trust, 1904, p. 22.3 Bcr. V. Inter. Kongress fiir nngewandte Chemir, Berlin, 1903, 3, 754AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 21 3Utilisation of Sewage.J. W. Leather1 has carried out experiments on the utilisation,for the sugar-cane crop, of the effluent derived from the work-ing of the septic tank system at Manjri and Poona (Bombay).Analysis of the sewage was made over a period of sixmonths, and the amounts of the more important plant-foods calculated and compared with the requirements of thesugar-cane during its period of growth. It was found thatthe sewage contained ample nitrogen and phosphoric acidfor the needs of the heaviest crops, although potash, possibly, wassomewhat deficient in amount.Drainage experiments on the soil tobe used were carried out, a millet (juar) crop being grown. As theplants grew, the drainage decreased, and after nine weeks-thesewage being applied as i t would be in practice-no drainage what-ever occurred. Of the phosphoric acid supplied in the sewage, nonewhatever was lost in the drainage, and also very little potash, notmore than 3 to 4 lb. out of 86 lb. supplied.c T op s.Food Grains and Fodders.J. W. Leather has made a very useful and much-needed com-pilation of the chemical composition of Indian food grains andfodders. All the analyses have been made in India, and, with fewexceptions, in the laboratory of the Agricultural Department of theGovernment of India.The list is a very complete one.Fmit.S. U. Pickering3 in the fourth Report of the Woburn Experi-mental Fruit Farm deals with the manuring of strawberries, goose-berries, currants, raspberries, and apples. He finds that withstrawberries suitable manuring gave, over a period of seven years,an average increase of 12 per cent., and that the use of artificialmanures alone gave results only 2 per cent. lower than those withdung. Small dressings were preferable to large, and in no casewas it necessary to exceed 12 tons of dung to the acre. Dung gavelarger-sized ,fruit and better quality, and the plants were morehealthy. A trial with the application of liquid artificialAgricultural Ledger, Calcutta, 1903, No.2 (Dictionary of Economic Products,Vol. V, M. 239).Ibid., No. 7 (Dictionary of Economic Products, Vol. 111, F. 669).Wohm Zxperimental Fmit Fanlz, Fourth Report, 1904 (Eyre & Spottiswoode)214 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.manures during the swelling of the fruit led to no advantage. I nthe case of gooseberries, dung produced a darker and more luxuriantfoliage, and a formation of larger berries, whereas artificial manuresproduced stinted bushes with poor yield. Dung also left the soil inbetter condition, but, as with strawberries, 12 tons to the acre wereample, The experiments with currants and raspberries were notvery conclusive, but, as regards apples, there was for the first fouryears an almost entire absence of effect from manurial treatment,the only exception being in the case of sodium nitrate applied inearly or late summer, this occasionally producing a good effect.Pickering holds that analysis of the soil affords but a poor guide tothe requirements of fruit trees.Banana.J.E. Higginsl finds that humus and potash are the principalrequirements of the banana crop, and refers to E. W. Hilgard’s2analysis of the ash of the fruit of the Chinese banana as containingmore than 60 per cent. of potash, while the ash of the leaves has 27gper cent. Lime and phosphoric acid are needed in smaller propor-tions, as is also nitrogen. The growing of leguminous green cropsand the ploughing of them in is recommended.Sweet Potatoes.H.H. Cousins has examined different varieties of theSweet potato grown in Jamaica, and finds the total solids tovary from 3943 per cent. to 30.58 per cent. The highest starchcontent was 30.94, the lowest 23.74 per cent. The sugars variedfrom 2.94 per cent. to only 0.232 per cent., and the nitrogen from 0.7to 0.16 per cent. Rather more than one-fifth of the nitrogen existsas amides. Cousins argues that the low amount of sugar found inmany cases is not enough in itself to account for the sweetness of thepotato when cooked and eaten, and he has made analyses of samplesof the same variety before and after cooking, the results showingthat, during the process of cooking, the glucose increased from 0.1 tcu4.3 per cent., and the total sugars from 1-6 to 7-69 per cent., thestarch being proportionately reduced.Also, on keeping for fiveweeks, a similar change was found to have occurred, the total sugarsincreasing from 1.1 per cent. to 4 per cent. during this period.Hawaii Agric., Exp. Station, 1904, Bulletin No. 7, “The Banana in Hawaii.”California Agm’c. Exp. Station, 1893.Bulletin of Dept. of Agricidttcre, Jamaica, Dec. 1904, 2, (l2), 275AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 21 5Tobacco.Manurial experiments with tobacco were carried out by M.Lohmann? and pointed to potassium being chiefly of use for theleaves and roots, phosphoric acid for the stems, and nitrogen equallyfor all parts of the plant. Excessive manuring is to be avoided, aspromoting relatively greater development of sterns and roots. Driedblood was found to act favourably as a nitrogenous food.Chloridesand sulphates were considered unsuitable, as decreasing the burningproperties of the tobacco. Carbonates, on the other hand, actedf avourably.Tea.I n India, H. H. Mann2 has continued his researches into thechemistry 03f tea manufacture, these forming, indeed, the first seriousattempt to deal scientifically with this important subject. Mannhas shown in his former publications (“The Ferment of the Tea-leaf. Parts I and 11”) that the fermentation of the tea-leaf duringits manufacture is due to the presence of an enzyme of the natureof an oxydase, and that the quantity of enzyme present gives anindication od the quality of the tea that may be produced.Hefound, further, that during the withering of the leaf the amountof enzyme increased considerably, being sometimes twice as muchas that contained in the fresh leaf. This increase went on duringthe withering process until a maximum point was reached, and thenit decreased gradually. Following up this clue, he set about deter-mining more exactly the time at which, under varying conditionsof temperature and moisture, the best results were obtained.Another point established was the necessity of conducting thefermentation of the tea-leaf as far as possible under aseptic condi-tions, and the avoidance of handling of the tea-leaf. The use ofantiseptics during the process of fermentation was tried, butchloroform was found to destroy the enzyme, and salicylic acidalso slowly did the same.Up to the present no sal;isfactory anti-septic has been discovered, and reliance has t o be placed on theabsolute cleanliness of all implements used.Suyar- Bee t .H. W. Wiley3 has collected the results of experiments carriedout simultaneously at ten experimental stations in the UnitedStates for the purpose of showing the influence which environmenthas on the composition of the sugar-beet.Landw. Vcrsuchs-Stat., 1904, 58, 439.Indian Tea Association, Calczidta, 1904, No. 2, “ The Ferment of the Tea-leaf,Part I1 I. ” U.S. Dept. of Agric., Bulletin No. 78216 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.MiIk.H. D. Richmond gives, from analyses of more than 15,000samples of milk examined in 1903, the average composition as : totalsolids, 12.78 per cent.; fat, 3.83 per cent.; solids-not-fat, 8-95 percent.Richmond further criticises Storch’s view as to the fatglobules of milk being surrounded by a membrane of mucoid sub-stance, a view in which Storch is supported by M. Beau. Richmondshows that all the observations which Sto’rch has made can be ex-plained without the assumption of the existence of a mucoidmembrane, and he gives other experiments which tell against thetenability of such a theory.(Groningen), as the result of investigations, comesto the conclusion that the liquid fatty acids of fat in milk do notoriginate from the cow herself, but are, for the greatest part a t least,formed from the butyric acid ferments in the paunch, especiallyfrom the readily digestible carbohydrates.in Northumberlandhave both dealt with variations found in the milk of dairy herdsand of individual cows comprising them.They both agree as tothe influence of the variations found with individual cows prac-tically disappearing when the mixed milk of a sufficient numberforming a herd is taken, and attribute the variations more to theidiosyncracies of individuals than to any regular influence of food,weather, or other conditions. Collins, however, contends that thequality of milk in the north of England is generally inferior to thatin the south.The use of hydrogen peroxide for preserving milk has been intro-duced by A. Renard,5 1.5 per cent.of a 12-volume solution beingsuggested. If this quantity is added, it is entirely decomposed intowater and oxygen in from six to eight hours, Larger quantitiesdecompose much more slowly, and with 5 per cent. added someremains undecomposed even after several days. Milk, although notsterilised by a small quantity of hydrogen peroxide, will, after suchtreatment, keep much longer than ordinary milk.Milk in a dry form has now been obtained by boiling milkviolently in limited quantity on a heated surface a t a temperaturerather more than 100’; a cushion of steam is formed between theheated surface and the milk, scorching is thereby prevented, and alsoB. SjollemaT. S. Dymond in Essex and 5. H. CollinsAnalyst, 1904, 29, 180.Bm. l? biter.Korigress f k r angewandte Chenzie, Berlin, 1903, 3, 831.Report of County Technical Laboratory, Uhelmsford, March 1904, “ VariationsJ. SOC. Chem. Id., 1904, 23, 8, “The Composition of Milk in the Northin the Milk of a Dairy Herd.”of England.” Mon. Sci., 1904, 18, 39AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 217the formation of a skin. The heated milk is then drawn in a very finefilm on to a heated surface and removed almost at once. This iseffected by having two steam-heated cylinders (heated rather abovelooo by a pressure of 40 lbs. of steam within them), and the milk isfed continuously between them, so that it is kept violently boilingon these surfaces. It then passes between the two cylinders as theyslowly revolve, and is carried on in a thin, uniform film, its waterbeing thus rapidly evaporated.While still apparently moist, itpasses a knife edge, and comes off the cylinder in a continuous sheetbefore it can get discoloured, and on cooling becomes perfectly dry.It can then be taken up with water and used as milk again. Theretention of a limited portion of water is necessary, so as to supplywater of crystallisation for the milk-sugar and thus prevent changestaking place in this substance.lBacteria.Beyerinck 2 confirms Natanssohn’s observations as to thepresence in sea-water of bacteria that reduce carbon dioxide byoxidation of hydrogen sulphide or thiosulpha,tes. He furtherobtained a bacterium, Thio bacillus denitrificans, which utilises freesulphur, converting carbonates and nitrates into sulphates andliberating carbon dioxide and nitrogen.A s s ina i I u t i o 32.G.L. C. Matthaei3 has determined the assimilation ofcarbon dioxide by plants at different temperatures from -6’ to4 5 O , and finds that there is a maximum assimilation specific to eachtemperature. During assimilation the temperature of the leaf rises.G e 9- m iita ti o nA. Wilson4 maintains that enzymes are not the primary causeof the germination of grain, their appearance being the resultrather than the cause. The real starting agents of germinationhe holds to be the lactic acid bacteria, which, developing acid fromthe ready-formed sugars during steeping, dissolve the insolublealbumin and liberate the enzymes. H e shows that if anythinginimical to the bacteria, although harmless to enzymes, be present,germination will not take place.E.Urbain5 finds that the origin of the carbon dioxide in ger-Ber. V. biter. Kongress fiir angewnndte Chemie, Berlin, 1903, 3, 887.J. Anzer. Chem h’oc., 1904, 26, 289.* Ceiitr. Bnkt. Par., 1904, 11, 593. Proc. lioy. Xoc., 1903, 72, 355.Coiizpt. rend., 1904, 139, 606218 ANNUAL REPOBTS ON THE PROGRESS OF CHEMISTRYmination is not the atmospheric air, but that i t proceeds from thehydrolysis of proteid matter by the proteolytic enzyme. NicolaCastor0 has confirmed the earlier observations of Lawes, Gilbert,and Pugh, and also Boussingault, that in germination no appre-ciable evolution of free nitrogen takes place.Attention has been drawn to the impregnation of seed with fer-tilising materials before sowing it, with a view to assisting germina-tion.This has been done a t the Woburn Experimental Station (seepage 204), and Issleib,2 of Bielefeld, advocates the use of a mix-ture of the following salts in equal proportions: ammonium nitrate,potassium nitrate, ammonium phosphate and sodium phosphate,1 kilogram of the mixture in 5 kilograms of water, the seed to besoaked for 48 hours, then dried and sown. This, it is maintained,will give the first needed stimulus to development and will result inan increase of yield.Organic Acids i n Plants.E. Charabot and A. HBbert3 believe the organic acids in plantsto be oxidation products of carbohydrates. The acidity due tovolatile acids is always highest in the leaves.The combinedorganic acids increase in amount in the absence of light, anddecrease if inflorescence is suppressedOxalates were found by W. Benecke” to be produced in themaize-plant when grofwn with sodium nitrate, but not when am-monium salts were used. Amar5 concluded from his experimentsthat calcium, supplied as nitrate, was entirely assimilated up to acertain point (varying for each species of plant), and that anyexcess was eliminated as oxalate, the formation of calcium oxalatebeing, not, as has been supposed, to eliminate oxalic acid, butrather calcium.Enzymes.To VinesG we are indebted for setting forth very clearly the pre-sent position of our knowledge of the part that enzymes play inproteid digestion, and he has traced out the connection between theproteid digestion in animals and that in plants.The presence of afibrin-digesting enzyme only occurs in certain plants, and there isno evidence of its independent existence, but there has been dis-covered a protease of the nature of e r e p i n , which is very generally“Ein Vorschlag zur Steigerung derLandw. Verwchs-Stat., 1904, 60, 41.2 Landw. Presse, No. 84, October, 1904, 31.Getreideertrage durch lmpragnation des Saatgutes mit Niihrsalzen. ”Coinpt. rend., 1904, 138, 1714.Compt. rend,, 1903, 137, 1301.Bied. Cenlr., 1904, 33, 387.Linnean Soc., December 1, 1904AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 219present in plants. Vines,l in another contribution, draws atten-tion to the fact that the yeast plant, although a single cell, pro-duces a variety of enzymes or ferments, among these being diastase,invertase, zymase, as well as protease, an enzyme which digests pro-teid matter.The nature of the latter he has investigated moreclosely and finds it to consist of two proteases, the one an erepsin,the other probably a trypsin.A. Brachin2 has found Zactase to be present in a large numberof plants, although absent in certain individuals. Its action isarrested by acetic and oxalic acids, but not by tartaric acid, exceptin large amount.B. Abelous and Aloy3 have found in the juice of potato pulpan oxido-reducing enzyme similar to that in the animal organism,and acting as an oxidising enzyme to some substances, and as areducing one to others,In the seeds of several plants has also been found by S.Fokin4a n enzyme capable of decomposing fats into glycerols and fattyacids. He considers that when the enzyme is truly present there isa quantitative relation between the yield of fatty acids and theamonnt of seed used.C. van Iterson, jun.,5 attributes the power which fungi in generalhave of attacking cellulose t o an enzyme, to which he gives thename cellulase.A. Fernbach,6 by comparing the small, light granules of potatostarch with the large, heavy ones, and determining the phosphoricanhydride in each, comes to the conclusion that the small granulesconsist of a nucleus relatively rich in phosphorus, on which aregradually superposed layers of starch free from phosphorus.G. Barger ’ has isolated from Saponaria officinalis the glucosidesaponaria, known as “ soluble starch.” By hydrolysis with mineralacids, glucose is produced and also a substance, saponaretin, closelyallied to the flavonm.From the valuable record of work issued by Horace Brown fromthe Guinness Reseaxch Laboratory comes a most welcome newmethod for the rapid estimation of starch in barley and malt.Linnean Soc., February 4, 1904.J.Pharin. Chinz., 1904, [vi], 20, 300.Compt. rend., 1904, 138, 382.Cliem. Rev. B’ett. Ham.-Ind., 1904,i1111, 30.Centr. Bakt. Par., 1904, 11, 689.Cmpt. rend., 1904, 138, 428.7 Brit. Assoc. &port, 1904 (Chemical News, 1904, 90, 183).8 Trans. Guinness Research Lub., 1903, 79220 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.This depends on the fact that when starch is hydrolysed by activediastase under suitable conditions there is a well-defined resting-stage in the action, approximating closely to the equation:100 parts of starch thus yielding 84.4 per cent.of maltose. Hence,if starch of barley or malt be converted by diastase so as to ensurehydrolysis according to the above equation, the determination ofthe maltose from its cupric-reducing power should give the directmeasure of the original starch present. The grain is finely ground,extracted with alcohol, then treated with malt extract, and thestarch calculated from the cupric-reducing power of the solution.Three hours’ extraction with alcohol is needed for barley and ninefor malt. A malt with diastatic power of 80 Lintner should be used.Numerous experiments with the process have given very satisfac-tory results in compasison with O’Sullivan’s method.The investigations a t the Guinness Laboratory have been mainlyconcerned with the changes which barley undergoes during theearly stages of the germinative process. The nitrogenous consti-tuents of barley and malt, especially those called the “ soluble ncm-coagulable albuminoids,” have been closely studied, the differentmethods for their estimation examined, and modifications of thesehave been made or fresh methods devised. Much attention hasbeen given to the estimation of amides and amido-acids, and oftyrosine in presence of mixtures of these.Further, the estimation of the total amount of nitrogenous sub-stances soluble in water has been worked out f o r the purpose ofgetting standard methods for extraction with water; also, the in-fluence of inorganic salts, especially sodium chloride, on the “ globu-lins ” has been studied. The second part of the records is concernedwith the giving of more definiteness to those ‘( points ” which “ ex-perts ” are accustomed to take into consideration when judging ofthe “ quality ” of barley. I n this connection the “ mealiness ” ofgrain, the changes it undergoes by steeping, and the meaning of“maturity” are specially dealt with. The whole forms a mostvaluable record of scientific work.Phosphorus in Foods.Inquiries by E. B. Hart and W. H. Andrews,l as alsoby A. J. Patten and E. B. Hart: have led to the con-clusion that vegetable feeding-stuffs do not contain phosphoruaRmer. Chem. J., 1903, 30, 470.New York Agr. Expt. Station Bzdletin, 1904, No. 250AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 221to any appreciable extent in inorganic combination ; germinat-ing grains, they find, are rich in organic phosphorus, andthis is not transformed into organic forms during germina-tion. It is suggested in the case of wheat-bran that thesoluble phosphates exist in the form of a magnesium-calcium-potassium salt of a phospho-organic acid. Phosphorus in organiccombination has similarly been found by Weirich and Ortlieb inwines.Nitrogen in Wheat.finds that the relation of gluten to total nitrogenin the case of different varieties of wheat frequently varies, andthat the gluten must be determined separately and not be takensimply from the estimation of total nitrogen.E. FleurentA r s e n i c in Barin Crops.Field experiments3 conducted on cereal and root crops withsuperphosphate free from arsenic, and with superphosphate con-taining arsenic, or to which arsenic in varying proportions wasadded, showed that the use of artificial manures was not a cause ofthe contamination of barley (to be used in brewing) with arsenic.I n no case was arsenic found in the ripe barley grain, or in thebulbs of the roots. Very small quantities were, however, detectedin the straw of the cereals and the leaves of the root crops.J. AUGUSTUS VOELCKER.Chcnt. Zeit. 1904, 28, 153. Compt. rend., 1903, 137, 1313.Report of the Royal Commission on Arsenical Poisoning, 1904

ISSN:0365-6217    

DOI:10.1039/AR9040100192

出版商:RSC    

年代:1904

数据来源: RSC

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MINERALOGICAL CHEMISTRY.ADVANCES in mineralogical chemistry consist for the most part of con-tributions to our knowledge of the composition of minerals, in theshape of analyses scattered in short papers through the pages of manyperiodicals, Work resulting either in the discovery of new principlesor in the co-ordination of established facts is only of rare appearance.A report on the progress of this branch of science must therefore, fromthe necessities of the case, partake somewhat of the nature of acatalogue, and the compiler, in marshalling his material, has first tosettle whether to aim at completeness, or, failing this, has only to decideon a standard by which to try the importance of the facts claimingadmission to his chronicle.The second course, in spite of the disadvantages attendant on theintroduction of a large personal equation, is the one which will beadopted by the present writer.In the following pages an attemptwill be made to give a brief outline of progress in what may be termedthe general and physical chemistry of minerals, and to this willsucceed a list of analyses, important because throwing light on thechemical formula of the material analysed, or noteworthy on accountof the rarity or peculiar properties of the mineral examined.General and P l ~ y s i c a l Chemistry of Minerals.With the advance of physical chemistry, attempts have naturallybeen made to apply the principles derived from the study of aqueoussolutions and mixed crystals to the elucidation of problems in miner-alogy and petrology.Research of this kind, which has so far been chiefly directed to theinvestigation of salt deposits and of crystalline igneous rocks, has ledduring the year to important results in each of these fields.Salt Deposits.-To van't Hoff and his pupils1 we owe five more,Nos.xxxiv-xxxviii, of those " Investigations into the Conditions ofSitzzmgsbcr. K. Akad. Wiw Berlin, 1904, 518, 576, 659, 935, 984 ; Absty., 1904,ii, 417, 492, 561, 570.A useful summary of vaii't Hoff's earlier work 011 this subject has been publishedby E. F. Armstrong, Brit. Assoc. Report, 1901, 262MINERALOGICAL CHEMISTRY. 223Formation of Oceanic Salt Deposits,” which have now practically solvedthe complex problem of the Stassfurt beds.Of these memoirs, xxxiv and xxxv give an account of the studyof the maximal tension and composition of the constant solutions at83O.The salts the mutual relations of which are considered are:bischofite (MgC1,,6H,O), carnallite (KC1,MgC1,,6H20), glaserite( 3K,S0,,Na,S04), kainite ( KCI,MgS0,,3H20), kieserite (MgSO,,&O),langbeinite (K2S04,2MgS0,), loeweite (Na,S04,MgS04, 2&H,O), thenar-dite (Na,SO,), and vanthoffite (3Na,S0,,MgS04). The results aretabulated and represented graphically.Number xxxvi, an especially important paper, gives a review ofprevious results and traces the conditions under which combinationsof minerals separate from solutions a t temperatures between 25’ and83’.2K20,2Mg0,1 1 B,0,,20Hz0is described in number xxxvii, and the identity of the mineralsmamanite and polyhalite is established in number xxxviii.I n thisconnection, it is of interest to note that C. Przibyllal finds that thesum of the molecular volumes of sylvite (KC1) and bischofiteis 165.39, while the molecular volume of carnallite (KC1,MgC12,6H20)is 173.57. The application of pressure t o carnallite will thereforetend t o produce sylvite and bischofite, thus suggesting an explanationof the occurrence of the latter salt in veins of crushed carnallite.Dolornitisation.-An important contribution t o this subject hasbeen made in the publication by the Royal Society of the results ofa chemical and microscopical examination of the core obtained fromthe bore-hole put down in the Atoll of Funafuti.Under the direction of Prof.J. W. Judd, no fewer than 133 analyseswere made of material from the main core. The results show that therock is almost entirely composed of the carbonates of calcium andmagnesium. The amount of calcium phosphate present is very small,0.124 to 0.288 per cent., and the quantity of insoluble matter almostnegligible, 0.001 to 0.083 per cent. Organic matter occurs in theupper part of the core, bnt below 50 feet the quantity present isinappreciable.I n the upper part of the reef the proportion of magnesium carbonateincreases from the top downwards till maxima of about 16 per cent.are reached at depths of 16 and 25 feet respectively, with a minimumof 12 per cent. between. Below 25 feet, the quantity of magnesiumcarbonate decreases, and from 50 feet down to 637 feet does not exceed5 per cent.From 637 feet to 658 feet, the proportion of magnesiumcarbonate rapidly increases to 40 per cent., a value which is maintainedThe preparation of the two salts K,Ca,(S0,)6 and(MgC1,,6H,O)Cerbtr. Miv~., 1904, 234 ; Abstr. 1904, ii, 416224 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.with slight variations to the bottom of the core (11144 feet). Thepercentage (45.65) required to form dolomite is never quite reached,ihe nearest approach being 43 per cent. at 950 feet,A microscopical examination made by C. G . Cullis has establishedthe interesting fact that aragonite crystals are only met with in theupper parts of the core, dolomite crystals only in the lower.I n the discussion of the bearing of these observations on theories ofdolomitisation, it is pointed out that the quantity of magnesiumcarbonate secreted by organisms in forming their skeletons does notseem to exceed 1 per cent.of the total weight, but that after the deathof the organism the proportion of magnesium carbonate may beincreased by the leaching out of calcium carbonate. This view is inharmony with what is known as to the solubility of the carbonatesof calcium and magnesium, and the presence of the latter in the upperpart of the reef may be attributed to such a process. The greatincrease in the amount of magnesium carbonate in the lower part ofthe core, below 637 feet, is probably due t o some other cause, possiblyto an interchange of bases with the sea-water, and it seems likely thatan attack on this problem by the aid of the methods developed byvan’t Hoff may lead to important results.UrccZitisation.-L.Duparc and T. Hornung 1 have studied thisphenomenon by means of a series of rocks from the Northern Urals,which show all stages in the passage from pyroxene to green amphi-bole. The analyses, I. pyroxene, 11. amphibole, of these mineralsseparated from the rocks are inconsistent with the view t h a t the pro-cess of uralitisation is one of molecular transformation. Moreover, asthe rocks are perfectIy fresh, the phenomenon cannot be explained asdue to hydrochemical alteration. The authors therefore suggest thatafter the pyroxene had crystallised out it was acted on by theresidual magma and converted in patches into amphibole.Loss onSiO,. A1,0,.Fe,O,. FeO. CaO. MgO. K,O. Na,O. ignition. Total.I. 50.91 2.64 - 10.07 23.33 13.30 - - - 100-2511. 43-34 12.60 10.44 7’92 13-06 12-60 0.02 1.90 0’22 102.10XiZicates.-The study of the compounds which crystallise out whenmolten mixtures of silicates are cooled has long been a favourite onewith mineralogical chemists, and, thanks to the researches of theFrench school, methods for the preparation in the laboratory of crys-tals of many of the most important rock-forming minerals have beenknown for a number of years. Research of this kind has of late re-ceived a special stimulus, partly due t o the growing conviction t h a tthe crystallisation of silicates from molten magmas must follow lawssimilar to those which the advance of physical chemistry has shownContpt.reitd., 1904, 139, 223 ; Abstr., 1904, ii, 621MINERALOGICAL CHEMISTRY. 225to hold in the case of alloys, and of salts separating from solu-tions, and partly owing to the influence of Meyerhoffer,l who hasemphasised the importance of the eutectic point as conditioning thecourse of crystallisation. Among the most active workers in this fieldhave been J. H. L. Vogt and C. Doelter, the latter associated with anumber of pupils. The recent contributions of both these investi-gators deserve more than a passing consideration.At the close of 1903, Vogt2 published the first part of a workentitled Die SiZikatschrnelxlosunge.n, in which he sums up the results ofresearches conducted by him during the past twenty years.Incor-porated with the earlier matter are many new observations, and thebook sets forth a number of conclusions which are based partly onfacts already published, and partly on determinations of meltingpoints, &c., which are to be given in detail in the second portion, whichhas not yet appeared. Yogt’s observations have beeu made for themost part on furnace slags, and are chiefly concerned with ortho- andmeta-silicates belonging t o the olivine and pyroxene groups. H e hasalso examined a number of products obtained by R. Akerman, whofused together the constituents of certain silicates. These moltenmasses were in all cases quickly cooled under ordinary conditions ofpressure, Water, carbon dioxide, and fluorine, which play so large apart in the production of many rock-forming minerals, were excluded.The slags most exhaustively studied were composed of silicates ofcalcium, magnesium, and iron.I n such substances, a number of well-defined minerals may be detected, as, for instance, olivine, enstatito,augite, wollastonite, gehlenite, &c. I n order to compare the composi-tion of the various slags, the following graphical method was em-ployed: it was assumed that in the metasilicates magnesium andiron replace one rtno ther in all proportions, and the ratios (Mg,Fe)O : CaOwere plotted as abscissa, while the ‘‘ degrees of acidity ” were plottedas ordinates, the degree of acidity being defined as the ratio, oxygencombined with acid : oxygen cambiued with base.Thus for a typicalorthosilicate, 2R,O,SiO,, the degree of acidity = I , while for a meta-silicate, R20,Si0,, the degree of acidity = 2. It will be seen that thecompositions of a number of slags, &c., can in this way be representedby points on a diagram. The mineralogical character of the crystalscorresponding with each point was then carefully determined, and onexamining the diagram it was found that it. broke up naturally intowell-defined mineralogical fields. I n other words, it became evidentthat a particular mineral only crystallised out when the slag had acomposition varying between fairly well-defined limits. On over-Zeit. Kryst. Min., 1902, 36, 593.Die Silikatschmelzlosungen. Von J. H. L. Vogt. 1903.Christiania. pp. v andSee also Cen17. Min., 1904, 49. 161.VOL. I. 226 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.stepping these limit's, another mineral took its place. To the exactdelimitation of the field proper to each rniner:d, Vogt has devoted animmense amount of study. The results are set forth in a strikingcoloured diagram, constructed on the principles described above froina large number of analyses, and are fully discussed in the text, whichalso deals with silicates containing manganese,As specimens of the facts observed, we may cite the following:the limit between true olivine and augite is reached when the fusedmass has a degree of acidity represented by 1.6. Again, obliquepyroxenes and calcium metasilicates (occurring either as wollastoniteor as hexagonal crystals) crystallise from magmas the acidity ofwhich ranges between 1.65 and 2-50 ; if the ratio Ca : Mg in the magmais greater than 7 : 3, calcium metasilicate separates ; if it is less, anoblique pyroxene is the result.Slags containing calcium and alumi-nium were also investigated in the same way, and a similar diagramconstructed. I n this connection, Vogt devoted special attention to theseries of minerals known as melilites. He has shown that they are tobe regarded as mixed crystals composed of gehlenite, R,Al,Si,Olo andAkermanite, R4Si,01,, where R = Cla, Mg, Fe, &c. The latter substancehas not been found as a mineral, but Vogt has succeeded in preparingit in tetragonal crystals having the composition (Cti,Mg),Si,Olo.These observations, many of which were made as far back as 1884,led Vogt to the general conclusion t h a t the nature of the mineralswhich crystallise from a molten mass depends essentially on thechemical composition of that mass. The minerals are, in fact,products of t'he chemical affinities of the predominant constituents,and mass action plays a decisive part in their formation. Moderatechanges in khe physical conditions under which they are produced,such as the temperature to which the mass has been heated, the rateat which it is cooled, the pressure under which it crystallises, eitherexert no influence at all, or modify but slightly the course ofcry stallisation.As the outcome of his later work, he now lays down the propositionthat the boundaries between the various fields on the diagramdescribed above indicate the composition of the eutectic mixtures ofthe minerals concerned.Again, from the study of the order ofcrystallisation deduced from microscopic examination of thin sectionsof slags, he finds that the mineral which is in excess as regards theeutectic point comes out first, although the phenomena are sometimescomplicated by effects due to supersaturation. If the melting pointsof two minerals are nearly the same, the eutectic mixture consists ofabout equal proportions of the two constituents ; if, on the otherhand,the melting points are very different, the eutectic contains an excessof that constituent which has the lowest melting point. The meltinMINERALOGICAL CHEMISTRY.227point of the eutectic may lie from 200' t o 400' below that of themost fusible constituent. The proportions of the componmts of someof the eutectic mixtures he has investigated are as follows : diopside45 per cent. and calcium metasilicate 55 per cent.; augite 70 percent. and olivine 30 per cent. ; orthoclase '74% per cent. and quartz254 per cent.Further, he comes to the conclusion that silicates are but slightlydissociated on fusion, and that we may apply to their mutualsolutions the van't Hoff formula for finding the depression of thefreeziog point, t = - - (where m is the weight of solute in 100grams of solvent, M the molecular weight of the solute, T the meltingpoint of the solvent in absolute temperature, X its latent heat offusion).Working on these lines, he finds that the formula CaMgSi,O, mustbe assigned to diopside when in solution, whilst olivine is repre-sented by the simple formula Mg,SiO,, and the anorthite molecule byCa Al,Si,O,.These important conclusions are largely based on the results ofpyrometric measurements as yet unpublished.1Vogt has also attempted t o classify the series of mixed crystals metwith among the silicates by means of the principles established byBakhuis-Roozeboom in his work on the solidification points of mixedcrystals of two substances. He adduces evidence t o show that theolivine and augite series may both be assigned t o type I of thescheme drawn up by Bakhuis-Roozeboom, and discusses the positionof the melilite series and of the plagioclase felspars without arrivinga t any very definite results.He concludes by expressing his conviction that it is in this direc-tion we must seek the path to be followed in future investigation.While Vogt has attempted to apply the principles of physicalchemistry t o the study of silicates, C.Doelter and his pupils 2 feelthat the time is hardly ripe for such an enterprise, and find them-selves compelled to traverse some of Vogt's conclusions.On the experimental side, Doelter has determined ( I ) the meltingpoints of a number of silicates, (2) the melting points of mixtures oftwo silicates taken in various proportions, (3) the melting points ofthe glasses obtained when molten mixtures are quickly cooled.H ehas also studied the products which crystallise from the fused masses,and has determined the limits of temperature between which theyseparate and the order of their appearance.m 0.022'2Jf' x1 The second part of Vogt's work appeared as these pages were in the press,a C. Doelter, Xitmngsber. K. Aknd. WisS. Wien., 1904, 113, i, 177. M. VuEnik,Ccntr. Min., 1904, 295, 340, 364; B. Vukits, Centr. Min., 1904, 705, 739.Q 228 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.In determining melting points, Doelter makes use of electricresistance furnaces of various types, and measures the temperatureby means of a rhodium-platinum thermo-couple. The following aresome of the values obtained : anorthite, 1230' ; labradorite, 1210O ;albite, 1150-1160°; orthoclase, 1210" ; adularia, 1215'; diopside,1255O ; augite, 1 185' ; olivine, 1280" ; leucite, 13 10' ; magnetite,1250"; achmite, 965". It will be noticed that the melting points ofthese important minerals lie within a comparatively narrow range oftemperature.On making mixtures, in various proportions, of pairs ofthese minerals, it was found that the melting point of the mixturelies between the melting points of the components and often approxi-mates to the arithmetic mean of these. Here there is no indicationeither of lowering of the melting point or of the existence of a eutecticmixture.On the other hand, the glasses obtained on rapidly cooling themolten masses fuse, as a rule, a t temperatures below the meltingpoints of the most fusible of their constituents.I n order to study the order of crystallisation, Doelter employed avery small electric resistance furnace, which could be placed on thestage of a polarising microscope.The silicates to be examined weresupported in the furnace on dishes made of quartz glass. By the aidof this ingenious device, Doelter has shown that a number of the mostimportant rock-forming minerals separate at temperatures which liebetween 1180' and 930". He has, moreover, been enabled t o studythe effects of supersaturation, and to observe the formation of newsubstances resulting from chemical action taking place between thetwo silicates when melted together.The general conclusions to which these researches have led him areas follows : when two minerals are fused together and allowed to cool,we may meet with the following phenomena.(1) The two minerals separate out again.I n this case, we may find ( a ) that the mineral present in largestquantity comes out first.Here the eutectic point is of importance;( b ) that the two minerals separate alternately or simultaneously.This phenomenon, which is a common one, is due t o superfusion. Theorder of crystallisation may often be reversed by introducing a crys-tal of one or other of the components; ( c ) that the less plentifulconstituent crystallises first. This is t o be attributed t o the compara-tive insolubility of the compound and is often observed.(2) New compounds separate in addition to the original ones, orone of the compounds changes into another.(3) Only one mineral separates.I n this case, the second constituenteither remains in the form of glass or is taken up by the otherMINERALOGICAL CHEMISTRY. 229anomalous mixed crystals being formed. This case is but rarely metwith.Further, he believes that the molten silicates are highly dissociatedfznd contain molecules of oxides, FeO, MgO, &c., as well as moleculargroupings, such as KAlSi,06 and KAlSi,O,. On cooling, simpleoxides and aluminates separate out first, followed by the simplersilicates, and then by the more complex ones. It will be observed thatinany of Doelter’s results appear to be incompatible with the viewsadvanced by Vogt, and this is more especially the case with thoseobtained from experiments made to test the validity of the van’t Hoffformula when applied to the calculation of the molecular weights ofsilicates.These experiments gave such discordant values, even in thesimplest cases examined, that Doelter concludes that we are not justi-fied in applying the formula to mixtures of molten silicates. H epoints out, moreover, that we should hardly expect it to yield resultsin the case of solutions which are in many instances highly concen-trated and probably often much dissociated.New Minerals.The following new minerals are of interest.Astyolite, described by R. Reinisch,l is found as small, greenish-yellow spheres imbedded in a black carbonaceous rock which occursin a diabase-tuff a t Neumark in Saxon Vogtland. The opticalcharacters suggest orthorhombic symmetry, and from an analysis themetasilicate formula (AI,Fe),Fe( Na,K),(SiO,),,H,O has been deduced.Co?*orbadite is an opaque mineral not unlike psilomelane in appear-ance.It occurs in the Clifton-Morenci district, Arizona., and hasbeen described by Lingren and Hillebrand.2 Analysis of material notquite free from impurity led to the formula R”Mn,O,, where R” standsfor P b and Mn, the former predominating. Small quantities of c‘u,Zn, and Fe are also present.Cs-yolithionite, described by N. V. Ussing,, is a well-defined mineral,occurring in large, colourless, rhombic dodecahedra in the cryolite ofIvigtut, Greenland. Analysis of pure material established thoformula Li,Na,Al,Fl2. This substance is interesting as containingthe highest percentage of lithium of any mineral yet known.Although it has certain points in common with cryolite, it is crystallo-graphically more closely related t o the garnet and sodalite groups.Erikile has been described by 0.B. Boggild4 from the nephelite-syeniteCentr. Min., 1904, 108 ; Abstr., 1904, ii, 268.Amer. J. Sci., 1904, 18, 448.0wr.r. K. Danske Videnskab. Selsk. FoThandl., 1904, 3 ; Abstr., 1904, ii, 347.Meddel. o m Gronland, 1904, 26, 93 ; Abstr., 1904, ii, 49230 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.at the Tunugliarfik-Fjord, Greenland. The brown, well-developedcrystals are orthorhombic. On microscopic examination of a thinsection, the mineral is seen to consist of an intergrowth of twosubstances, of which the predominant one (erikite) is yellow, stronglyrefracting and birefringent, while the other, of which the refractionand hiref ringence are weak, is probably hydronephelite.An analysis ofthe mixture gave the following result :SiO,. P,O,. (Ce,La,Di,),O,. Tho,. A1,0,. CaO. Na,O. H,O. Total.15.12 17.78 40.51 3'26 9'28 1.81 5.63 6-28 99.67Erikite is placed in a group comprising compounds of silicates,titanates &c., with columbates, tantalates, phosphates, antimonates,&c. I n the cubic members of this group (pyrochlore, lewisite, kc.),the ratio of the acid oxides RO, : R,O, is = or < 1, whilst in allthe others it is = or 7 2.Noyencite is the name given by Lingren and Hillebrandl to afibrous, optically well individualised mineral observed by them from theClifton-Morenci district, Arizona.It consists chiefly of silica andferric oxide with small quantities of MgO, CaO, and FeO.Nuegite is a tetragonal mineral described by Tsunashiro Wada 2 fromNaegi, near Takayama, province of Mino. An analysis by T. Tamuragave the following results :SiO,. UO,. Tho,. Ta,O,. Nb,O,. CeO,. Fe,O,. CaO. MgO. H,O. Total.34.89 28'27 16-50 7-00 4.10 1.59 1'60 1.71 0'57 3'12 99.35Palmerite is a white, amorphous mineral resembling kaolin in appear-It occurs in a guano deposit near Controne, Salerno, Italy, and ance.has been described by E. Ca~oria.~ I t s formula isHK2A1,(P0J3,7H,0.Radiotine.-R. Brauns * has described the small spheres of thisfibrous mineral which occur in serpentine in the upper devonianpicrite of the neighbourhood of Dillenburg. Analysis showed thecomposition to be the same as that of serpentine, Mg,Si,07,2H,0,but it has a lower specific gravity and is not attacked by hydrochloricacid.TeaZZite.-This interesting Bolivian mineral occurs in thin graphite-like folia which have been determined by Prior to be probably ortho-rhombic. The analytical results agree very closely with those required1 Amw.J. Sci., 1904, 18, 455.2 Jfinerab of Japan, TGkyG, 1904. This work contains inany analyses of Japanesetninerals.A t t i Actad. GeorgoJU, 1904, [v], 1,Jahrb. Min., 1904 ; Bed.-Bd., 18, 285 ; Abstr., 1904, ii, 350.illin. Mag., 1904, 14, 21 ; Abslr., 1904, ii, 743MINERALOGICAL CHEMISTRP. 231for the simple formula PbSnS,.It exhibits relations to franckeiteand cylindrite.Y%o~innite.-Tliis mineral, first obtained by \V, D. Holland, has beendiscovered by A. K. Coomhra-Swamy in the bed of a stream nearKondnrugala, Ceylon, where it occurs in heavy, black, mater-worn cubiccrystals associated with zircon, ilmenite, and small quantities of anothermineral, probably thorite. A very small amount has also been dis-covered by Coomha-Swlimy in a pegmatite vein on the Ambalawaestate, Gampola. Analyses made in the laboratory of the ImperialInstitute under the direction of Prof. W. R. Dunstan 1 gave thefollowing results :Tho,. GO,. (La,Di),O,. ZrO,. UO,. Fe,O,. PbO. SiO,. Iiisol. Total.72.24 6.39 0.51 3.68 11-19 1-92 2-25 1'34 0'41 99.9376.22 8'04 trace 12-33 0.35 2-87 0'12 - 99'93Sir W.Ramsay 2 has also investigated this mineral and finds it tocontain helium.MineraE A rzccZpses.-During the year, fresh investigations of thechemical composition of a iiumber of minerals have been made. I nsome cases, the work has led to the confirmation or revision of doubtfulformuls, while in others it has been undertaken in the hope ofdetecting rare elements.Exnnaincction of Jlinerccls f o r Radioactiuity.-Owing t o the interestaroused by radium, a number of workers have determined the effectproduced by various minerals on photographic plates and in dischargingelectroscopes. Thus M. G. Bardet,3 using the photographic method,concludes that with rare exceptions all active minerals contain uranium,while B. B. Boltwood4 finds that the effect produced on an electro-scope is proportional to the percentage of uranium present.J.Hoff mann 5 has examined the uranium minerals from Schlaggenwaldand finds that torbernite, autunite, zippeite, and pitchblende rapidlyaffect a photographic plate, whilst the action of uranocher, uranotile, andgummite is less intense. Kolbeck and Uhlich,G workiiig on similarlines, find that pitchblende from Johanngeorgenstadt gives the bestresult. 8. M. Losnnitsch 7 has detected radioactivity in the cinnabarfrom Avala ancl Bare, in Servia, and from Idria in Austria. Heattributes the photographic action, which is weaker than that ofNature, 1904, 69, 510.Zbbid., 533, 559 ; A b s t ~ . , 1904, ii, 745.B d . Soc. franc. &in., 1904, 27, 63.Amer.J. Sci., 1904, 18, 97 ; Abstr., 1904, ii, 666.Zeit. p m k l . Geol., 1904, 12, 123, 172.Ccntr. Nin., 1904, 206.Ber., 1904, 37, 2904 ; Abstr., 1904, ii, 74232 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.pitchblende, to the presence of radioactive mercury, and points out thatthe barytes which accompanies the cinnabar is inactive.D. Mawson and T. H. Laby,l who have examined some Australianminerals, find that only those which contain thorium and uraniumexhibit a high degree of activity. H. N. McCoy2 has observed theeffect on an electroscope produced by twelve specimens of nraniumminerals, including pitchblende, gummite, and carnotite, chiefly fromAmerican sources. H e concludes, like Boltwood, that the activity isdirectly proportional to the amount of uranium in the ore.On com-paring the ores with pure uranium compouncls, he found that the formerwere I’roportionately inore fictive than the latter in the ratio of 5.7 : 1.He believes that his experiments support the theory that radium is adecomposition product of uranium. M. F. Pisani has examined by thephotographic method a very large number of minerals of all kinds. IIefinds that with but few exceptions, inclnding certain fluorides, all radio-active minerals contiin uranium or thorium or both. -Among the sub-stances which had the strongest effect, he notes thorite, orangite,euxenite, aeschynite, trogerite, zeunerite, niixite, turnerite, urano-circite, uranite, monazite, pitchblende, cleveitc, and violet fluorspar (fromCumberland). C.Winkler,* in the course of an interesting discussionentitled ‘‘ Radioactivitiit und Materie,” points out that, in spite of thechemical resemblance between radium and barium, we do not find radio-active barytes accompanying radium ores, the property being apparentlyentirely dependent on the presence of uranium. We must, however,notice in this connection that R. Nasini claims to have detected radio-activity in the barytes prepared from the Albano deposits.P r e s e n c e of Rare Elements in Certain Xinercds.Ge~nzoniunz is known to exist in franckeite (0.1 per cent.), in can-fieldite (1.82 per cent.), in a n iron-black mineral from Bolivia (4.99 percent.), and in argyrodite (6.42 per cent.). It has also been reported byKriiss in euxenite (0.1 per cent.) and by Chrustschoff in samnrskite(1.5 per cent.).The work of theso two authors has, however, beenrecently revised by G. Lincio,G who, after very careful examination,has been unable to detect the element either in samarskite from theUrals and from Mihchell City, or in euxenite from Kragero and Spange-reid. H e concludes that sulpho-salts afford at present the only knownsources of germanium.Proc. Roy. Soc. Xew South Wales, 1904, 37.Bcr., 1904, 37, 2641.Bull. SOC. fraq. Min., 1904, 27, 58 ; Abstr., 1904, ii, 530.Ber., 1904, 37, 1655 ; Abstr., 1904, ii, 462.Atti B. Accad. Lincei, 1904, 13, i, 367 ; Abstr., 1904, ii, 461.ti Centr. Min., 1904, 142 ; Abstr., 1904, ii, 348MINERALOGICAL CHEMISTRY. 233Indium and gallium have been detected with the spectroscope byRimatori in blendes from Sardinia.The percentage of indium wasestimated in R specimen from Riu Plnnu Castangias, weighing eightygrams, and the high value 0.12 per cent. obtained. These blendes werealso found to contain up to 0.79 per cent. of cadminm.to bepresent in most specimens of fluorspar. The remarkable sensitivenessto heat of fluorspar from Amelia Court House, Virginia, led to thisinvestigation; it becomes luminous when merely held in the hand for afew minutes. On finding that the arc spectrum of this fluorsparshowed the presence of yttrium and ytterbium, more than a hundredothers were examined. The specimens richest in the two elementsproved to be those from Amelia Court House, Corocoro, Bolivia, andLlano County, Texas.The two latter resembled the former in theirsensitiveness to heat. Of the English specimens examined, those fromCclmberland, Durham, and Northumberland showed a fair amount ofyttrium, those from Cornwall and Devoii but little.Yttrium and ytterbium have been shown by W. J. HumphreysSpecial Beccctions of dfinercbls.Culcite and Aragonite.-In 1901, Meigen pointed out that aragoniteand calcite could be readily distinguished by the colours of the productsobtained when the powdered minerals were boiled with aqueous solu-tions of cobalt nitrate. This discovery aroused considerable interesta t the time, and it was generally admitted that the differences in colourwere probably due to the formation of basic cobalt carbonates differingin composition. That this is actually the case has now been shown byA.LangeI3 a pupil of Rieigen’s, who has examined the composition ofthe substances produced under varying conditions of concentration.He concludes that the lilac-coloured compound made by boiling aragonitewith concentrated solutions of cobalt nitrate is 2CoC0,,3Co(OH),,H20~The blue compound obtained from calcite under similar conditions is prob-ably CoC03,3Co(OH),. If dilute solutions are employed, the productfrom aragonite is CoCO3,2Co(0H),, and calcite, if very finely divided,yields a substance of the same composition and colour. He finds,moreover, that the products obtained from aragonite are less liable t ooxidation than those given by calcite. If cobalt chloride is usedinstead of the nitrate, the results are on the whole similar to thosequoted, but if the sulphate is employed, so much of it becomes includedin the product that no satisfactory quantitative estimations can bemade.Atti 22.Accad. Lincei, 1904, 13, i, 277.Astrophysical Journal, 1904, 20, 266.Inaug. Uiss. Freibury i. Br., 1904234 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Cdcite wLd Dolontite -F. Hinden has proposed the following testsfor distinguishing between these substnnces. (A) The powderedmineral is shaken with cold 10 per cent. s3lution of ferric chloride. Ifcalcite is present, carbon dioxide is evolved and a brown precipitateproduced. Dolomite undergoes no change. The test inay be maderoughly quantitative by taking 1 grain of mineral and adding 5 C.C.ofa 5 per cent, solution of potassium thiocyanate. A cold solution of 10per cent. ferric chloride is then to be added, until after shaking a per-manent red colour remains. Under these conditions, 1 C.C. of ferricchloride corresponds with about 8 per cent. of calcite present. (B)Calcite boiled with a 10 per cent. solution of copper sulphate gives ablue b a G carbonate of copper, while dolomite remains unchanged.calls attention to the solvent action exerted onfinely divided quartz by caustic alkalis and alkaline carbonates a t 100’and by water a t 300’, and points out the application of this in theproduction of so-called ‘( Kalksandsteine,” of which there is a largeannual output in Germany. I n t h i s process, bricks are made froinquartz-sand and slaked lime nud heated for ten hours in a boiler a t174”.The particles of sand are then fonnd to be firmly held togetherby a cement formed by the action of the lime and silica, the resultbeing really a ‘‘ silicate sandstone.” From a microscopical examination,Rinne concludes that the cement is of a zeolitic nature, and that theexcess of lime becomes converted into calcite.Quartz.-F. RinneMin e r cc I A n a I y s e s.Arnblyyonite.-A pure specimen from a large deposit of the massivewhite mineral a t Pala, San Diego Co., California, analysed by W. T.S ~ h a l l e r , ~ gave the following results :P,O,. Al,O,. Fe,Oy. MnO. MgO. Li,O. Na,O. H,O. F.48.83 33’70 0’12 0.09 0-31 9.88 0‘14 5-95 2.29Ani;gorite.-Two specimens of this variety of serpentine have beendescribed by A.Hamberg4 from Persberg and the KO mine at Nord-marken respectively. Analyses by Elsa Cronqvist agree well withthe formula H,Mg,Si,O,, part of the MgO being replaced by FeO.Beg*yl.-The compositioii of beryl has been studied by J. H. P ~ l l o k , ~who finds that the beryllium oxide prepared from Limoges beryl canbe separated into fractions having different equivalents either by pre-cipitation with ammonium carbonate, by crystallisation of the sulphate,Ywh. nnt. Ges. Basel, 1904, 15, 201.Amv. J. S’ci., 1904, 17, 191 ; Abstr., 1904, ii, 348.TTMLS., 1904, 85, 1630.2 Ceqbt?.. dfi72., 1904, 333..I Ged. Fi;?.cn. i StocX.kol~n FijAmdl., 1904, 26, 67 ; Absti.., 1904, ii, 745MINERALOGICAL CHEMISTRY.235or by distillation of the chloride.Limoges contains at least one new element in addition to beryllium.from Pala, San Diego Co., California, was found by W. T. Schallerto be well represented by the formula CuS0,,H,0,6H20.CZmdetite.-A specimen of this monoclinic variety of arsenious oxidefrom Szomolnok, Hungary, has been analysed by J. Loczka,2 who foundin it 75.99 per cent. of arsenic; the formula As,O, requires 75.78 percent. The crystallography of the mineral from this locality has beenfully determined by Schmidt.CyZiizdrite.--Two specimens from Poop6, Bolivia, have beenexamined by G. T. Prior.3 U p to the present, the composition of thismineral has rested on an analysis by Frenzel. Prior's results lead himto regard cylindrite as a definite ininernl species of the probableformula 3PbSnS2 + SnFeSb,S,.He concludes that the mineral fromBoot?&e.-A massive specimen of this rare form of copper sulphatePh.Fe. Age Sn. Sb. S.35'24 2.81 0-50 25.65 12-31 23-8334.55 2-77 0 -28 25.10 12'98 23'88CyrtoZite.-A specimen of the altered zircon from Bedford, N.U.,examined by L. McI. L ~ q u e r , ~ contained 53.56ZrO2, 27*24SiO,, and4.35U2O,.Emmonsite. -A green substance occurring in mammillary forms atCripple Creek, California, has been identified with this rare mineralby W. F. Hillebrand.5 The analysis quoted below does not lead toany satisfactory formula.The latter is due to inclusions of uraninite.H2O H2OTeO,. Fe,O,. P,O,. A1,0,. SiO,. at 100". >loo".70.71 22.76 0-34 0 '56 0'88 0'21 4'54Fvanckeite.-In connection with his work on teallite and cylindrite(q.v), Prior has analysed two specimens of franckeite, I. from Poop6,IT. from the Trinacria mine near PoopB. A consideration of the resultsof these analyses, and of the values previously obtained by Winkler,leads him to suggest SPbSnS, + Pb,FeSb,S, as R probable formula forthe species.Pb. Fe. Zn. Ag. Sn. Sb. S.I. 46.23 2.69 0.57 0.97 17'05 11'56 21.1211. 48.02 2.74 - 0.99 13.89 13-06 20'82GudoZinite.-G. P. Tschernik has analysecl material from Idahoand Ytterbia.Amer. J. Sci., 1904, 17, 192 ; Abslr., 1904, ii, 348.Zeit. Kryst, Min., 1904, 39, 520; Abstr., 1904, ii, 666.Min. Mag., 1904, 14, 21 ; Abslr., 1904, ii, 743.AweTicnn Geoloyist, 1904, 33, 17.Amer.J. Sci., 1904, 18, 433.J. E w x Phys. Chew. Soc., 1904, 36, 287 ; Ahstr., 1904, ii, 419236 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Gismondite.-The formula of this mineral has been hitherto some-what doubtful, but n specimen from the basalt of Nicolstadt, nearLiegnitz, analysed by A. Sachs,1 gives results which agree well with(Ca,Na,,K2)Al,Si20,,4H20, the formula proposed by Zarnbonini.G'Zaserite.-The nature of this mineral has been the subject of apaper by €3. Gossner., He points out that conflicting views have beenheld by Retgers and van% Hoff, the former regarding glaserite as adouble salt of' the formula K3Na(S,0,),, the latter considering it to bean isomorphous mixture of hexagonal modifications of the components.Gossner has studied the specific gravity, crystallography, and chemicalcomposition of the products obtained under various conditions fromsolution of the sulphates and corresponding chromates respectively,and comes to the coriclusion that Retger's view is the correct one.HccZZoysite.-The pink clay from Pala, San Diego Co., California,has been shown by W.T. Schaller3 to have the formula H,A1,Si,09,H,0.1Zmenite.-A careful determination of the axial ratios, specificgravity, and chemical composition of specimens of this mineral fromvarious localities has been made by G. Doby and G. Melczer.* Theresults are as follows :Axial ratio,Locality. a : c. Sp. gr. TiO,. FeO. Fe,O,. CaO. MgO. Total.Snarum ..... ... 1 : 1.368 5'041 5-66 0.11 93.50 - 1.10 100.37Tvedestrand ...1 : 1.3716 4.910 21-58 8.04 70.39 - - 100*01llmen Mts ....... 1 : 1.3772 4.852 47.68 19.70 33.90 - 0.35 101*6SKragero ......... 1 : 1.379 4.614 49 68 15'72 34.51 0.07 - 99.98It will be noticed that as the percentage of TiO, increases, the c axisbecomes longer and the specific gravity diminishes.Kunxite.-The composition of this variety of spodumene, remark-able for its power of responding readily to radium radiation, has beencarefully investigated by R. 0. E. Davies.5 Analysis of very purematerial gave :SiO,. A1,0,. NiO. MnO. ZnO. CaO. K20. Na,O. Li,O. ignition. Total.64.05 27.30 0.06 0.11 0.44 0.80 0.06 0.30 6.88 0.15 100.15Loss onThese numbers agree with the formula LiAl(SiO,),. The followingelements mere tested for with negative results : Mg, Cr, U, Ti, Fe, Sr,Ba, Th, Zr, Ce, Y, P.There appears to be nothing in the compositionof the mineral to suggest an explanation of its unique properties.Lawsonite, from Marin Co., California, has been the subject of acareful crystallographic and chemical study by T. Schaller andCcntr. iMin., 1904, 215 ; AbstT., 1904, ii, 420.Zeit. Kryst. Alin., 1904, 39, 155.Amer. J. Sci., 1904, 17, 191 ; dbstr., 1904, ii, 348.Zeit. KrgsL. Min., 1904, 39, 526 ; Abstr., 1904, ii, 666.Amer. J . Sci., 1904, 18, 2 9 ; Abstr., 1904, ii, 621MINERALOGICAL CHEMlSTRY. 237W. F. Hillebrand.1 The mineral, which crystallises in the ortho-rhombic system, is essentially H,Ca A 12Si2010, some aluminium beingreplaced by ferric iron and some calcium by iron, magnesium, andpotassium.Lorandite.-New analyses of this interesting thallium mineral havebeen made by P.Jannasch,Z and by J. L o c ~ k a . ~ The results establishthe formula TlAsS,.ilIu,manite.-This mineral, found at Maman, in Persia, was describedby Goebel, who attributed to it the formula3CaSO,,K,SO,, 2MgSO,, 3H,O.Van't Hoff having failed to obtain it synthetically in the course ofhis researches on oceanic salt deposits, has made, in conjunction withG. L. Voerman? a new analysis of carefully selected material fromthe original 1oca.lity. He concludes that niamanite is identical withpolyhalite, 2 CaSO,,K,SO,,MgSO,, 2H,O.MispickeZ.-Crystals from Sulitjelma, in Arctic Norway, have beenmeasured by M.F l e t ~ h e r . ~ The axial ratios suggested glaucodote,but the analytical results obtained by J. A. Smythe indicate cobalti-ferous mispickel :A little titanium is also present.S. As Fe. co. Total.I. 21.76 42-20 35.31 1'32 100.5911. 21.96 42.15 36'17 0 98 101.26Pyrocl~Zore.-Analyses of a Scandinavian variety of this mineral,and also of the ilmenite and zircon which accompany it, have beenpublished by G. P. Tschernik.6Realyar. -Pure specimens from Allchar, in Macedonia, and fromthe Binnenthal, in Switzerland, have been analysed by P. Jannasch.7The numbers obtained agree very closely with those required by theformula ASS.Rhodornite.-Dark red crystals, very rich in faces, have beendescribed by L Colomba8 from S. Marcel (Valle d'Aosta).Theanalytical results may be represented by the formula 7MnSiO,,CaSiO,.8upphirine.-A rock composed of hypersthene, sapphirine, biotite,and hercynite is found in the Vizagapatam district of India. Thesapphirine has been analysed by T. R. B l ~ t h , ~ who deduces the1 Avter. J. Sci., 1904,17, 195 ; Absty., 1904, ii, 350. See also F. Zambonini, Atti2 Zeit. Kryst. illh~., 1904, 39, 122 ; Abstr., 1904, ii, 416.3 Zeit. KrzJst. Min., 1904, 39, 520 ; Abstr., 1904, ii, 666.K. Accad. Lincei, 1904, 13, ii, 466.Sitxunysber. K. A k a d . Wiss., B e r l i n , 1904, 994 ; Abstr., 1904, ii, 570.Min. Mag., 1904, 14, 5 4 ; Abstr., 1904, ii, 743.6 J. RSLSS. Phys. Chem Soc., 1904, 36, 712 ; Abstr., 1904, ii, 620.7 Zeit. Kryst. Min., 1904, 39, 114 ; Abstr., 1904, ii, 416.8 Atti R.Accccd. Sci. Turino, 1904, 39, 664 ; Abstr., 1904, ii, 571.9 &cords Geol. Sicrvey, I n d i a , 1904, 31, 38 ; Abstr., 1904, ii, 668238 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.formula Mg0,2Fe0,6A1,03,2Si0, from his results. Sapphirine havingthe composition 5Mg0,6A1,03,2Si0, (a small part of the MgO beingreplaced by FeO) has been previously described from Greenland. Itmill be noticed that the relative amount of oxides of the type R O isless in the Indian than in the Greenland specimen, while the proportionof FeO is much larger.SchixoZite.-A fresh examination of this mineral has been made by0. B. Biiggi1d.l The rose-red to dark brown crystals belong to theanorthic system, and the formula 9Si0,,6K”0,2(Na,H)20 is deducedfrom the following analysis by C.Christensen :SiO,. Ti07. Ce,O,. Y,O,. FeO. bInO. CaO. Na,O. H,O.51.06 0.62 0.94 1-03 2.74 9.84 22-89 9.97 0.55Boggild, however, after discussing two earlier analyses of the samemineral, suggests the simpler formula 3SiO2,2R0(Na,H),O, whichhas, moreover, the advantage of exhibiting the relation to pectolite.SodaZite.-A remarkable occurrence of this mineral has beenreported from Kishengarh, Rajputana, where it occurs in massesup to a foot across in veins of elsolite-pegmatite. The followinganalysis is by E. W. Vrendenburg :Loss 011Si02. B1,03. CaO. Na,O. C1. ignition.38.055 31.30 0.001 24.77 7-18 0.82Traces of Fe,O, and SO, were also found.8.2’7.turns pink, but loses the tint again when exposed to light.been published by E.Ta~coni.~The mineral is either bright blue or ColourIesB, its specific gravity isThe colourless variety, when kept in the dark for some time,Tets.a/zedrite.-An analysis of a specimen from Bocchegianno hasS. Sb. cu. A& Fe. zn. Total.23-41 27-73 30.69 6’62 3.47 6‘89 98.81.Traces of As and Mn were also indicated.As the analyst points out, the interest of the determination lies inthe fact that the results can be easily interpreted by aid of theformula proposed for fahlerz (tetrahedrite) by Prior and Spencer in1899, which in this case would be written as follows :Another specimen from Palmavexi, Sardinia, analysed by C,Rimat ori,4 gave numbers agreeing with the simple formula 4Cu2S,Sb,S,.1 Meddel.o m Gronland, 1904, 26, 93 ; Abstr., 1904, ii, 49.2 Eecords Geol. Survey, India, 1904, 31, 43 ; Abstr., 1904, ii, 667.3 Atti 8. dccad. Lincci, 1904, 13, i, 337.4 Rioista Af&z., 1904, 31, 46311NERALOGlCAL CHEMISTRY. 239Thuringite and chamosite from the deposits of iron-ore in the LowerSilurian of Thuringin, have been the object of an elaborate investiga-tion by E. R. Zn1inski.l The analytical results agree with the acceptedformula of thuringite, H,,(Fe,Mg),( Al,Fe),Si,O,, .Titanium Olivine.-Specimens from Chiesa in Val hhlenco havebeen described by L. Brugnatelli,2 and anttlyseil by Anelli. Thenumbers quoted below agree well with those given by material fromPfunclers and Einclelen, and lead t o the orthosilicate formula( H2,Fe,Mgj2( Si,Ti)O,.Traces of fluorine and manganese are present, and the amount OFwater appears to be constant :SiO,.TiO,. MgO. FeO. H,O. Total.36‘86 4.78 45.50 0.57 1 *57 98-28Topx.-In a paper on the quantitative determination of fluorine,I(. Daniel3 gives reasons f o r assigning to topaz the following con-O*Al:Ostitutional formula : F2:Si<0,A1 :o.74esuviccnite.-Most of the crystals of this complex tetragonalsilicate are optically negative. Those from Wilui, however, exbibitpositive double refraction, while others are known with intermediateproperties. Some years ago, Klein showed that similar phenomenaobserved in apophyllite appear to be connected with the amount ofthe volatile constituents, water and fluorine, present in the mineral.He has, therefore, examined the effect of heat on a large number ofspecimens of vesuvianite from different localities and finds that, withthe exception of the positive crystals from Wilui, they all pass overinto the normal negative type.has studied 83 analyses of vesuvianite, and concludes that the amountof water and fluorine are the determining factors, boron being ofsecondary importance.Xenotirne.-It has been suggested by Kraus and Reitinger thatxenotime, YPO,, is really a pseudomorph after hussakite,3R,O,, 3P,O,,SO,, sulphuric acid having been removed by the actionof water.Briigger,5 thinking this view improbable, caused someperfectly fresh xenotime from Aro to be tested for sulphuric acid.The result mas negative, and Bragger therefore holds that xenotime isa definite mineral species, closely related morphologically to hussakit e,to which he assigns the formnla S[YPO,],[(SO,,P)PO,].Seeking for an explanation, KleinJahi-b, Miw., 1904, Bei/.-EcZ., 19, 40 ; dbst?.., 1904, ii, 571.Zeit.Kryst. Miit., 1904, 39, 209.S’itzi~,ngsbe~. K. AEnd. Wiss. Berlin, 1904, 653 ; Abstr., 1904, ii, 668.L3 Zeit. nno?y. Chem., 1904, 38, 29’1.5 Nyt. iVq. i~~tzl.rvidensknberne, 1904, 42, 1240 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.A r t i f i c ia I Po rrn a t io n of Mirt er a Is.has continuedhis researches on the artificial production of phosphates, sulphates,and chromates, and has shown how hopeite, Zn3(P0,),,4H20,h~irkaulite, H2Mn,(P0,),4H,O, and crocosite, PbCrO,, may be preparedin measurable crystals.To obtain hopeite, a solution of 45 grams ofcrystallised zinc sulphate in 500 C.C. of water was mixed with500 C.C. of a solution containing 3’7 grams of sodium phosphate,Na2HPO,,12H,O. The precipitate which formed was dissolved in aslight excess of sulphuric acid, the solution kept warm on a water-bath, and very dilute ammonia (0.3 per cent.) allowed t o drop slowlyin (one or two drops per minute). A t the end of eight days, a cropof good crystals up to 4 mm. long was obtained, A solution ofmanganese carbonate in phosphoric acid treated in a similar mannerdeposited hurkaulite. Crocosite was formed when a dilute solution ofpotassium dichromate was dropped slowly into a warm solution oflead nitrate containing excess of nitric acid.A number of otherphosphates, &c., not hitherto found as minerals, have also been pre-pared by similar methods.Buby.-An interesting account of the production of this crystallineform of corundum by fusion of alumina mixed with a little chromicoxide has been published by A. Verneuil.2 The author employs avertical blowpipe fed with coal gas and oxygen. The flame is directeddownwards on to a support, the height of which can be slowly alteredas the process proceeds. Alumina in a fine state of division isgradually introduced through the pipe which supplies the blast. Bycareful attention to a variety of details there may be obtained on thesupport a stick of alumina terminated by a spherical mass ofcrystalline transparent ruby.Phosphates, &.-During the year, A.de SchultenM e t e o r it es.Catalogues of the important collections of the British Museum(by L. Fletcher), of the University of Berlin, and of the Ward-Coonley collection have recently appeared. Of these, the last isnoteworthy as being now the most complete in existence, containingrepresentatives of 603 different falls.The following list contains the names of some interesting meteor-ites of which descriptions and analyses have been published duringthe year.Caiion DiabZo.-H. Moissan has investigated the residue leftBull. Xoc. franq. Min., 1904, 27, 97.A m . Chinz. Phys., 1904, [viii], 3, 20 ; Nature, 1904, 71, 180.Cornpt. T B ~ K ~ . , 1904, 139, 773MINERALOGICAL CHEMISTRY. 241after dissolving 53 kilograms of this iron in hydrochloric acid.Hefinds that it contains amorphous carbon, graphite, and diamond, thelatter both in rounded forms and in brilliant crystals.Caiion City, Trinity Co., Cn~?~ornkc.-An analysis of this iron isquoted by H. A. Ward.1Cams Grandes, Mexico, is an octahedrite rich in taenite described byE. W. Cohen.2Linum, Brandenburg, is a chondritic stone. An analysis by Lindner isgiven by K l e h 3iVarraburra, New South Wciles.-This iron has been analysed by A.Liversidge.4Paulovka, Russia, contains, according to Klein,3 augite, bronzite,enstatite, olivine, anorthite, and perhaps leucite. It has been analysedby Lindner.Peyamiho, Gernzun East Africa.-This stone fell on October 24th,1899. It consists of about 30 per cent.of anorthite and 70 per cent.of pyroxene, and is classified by F. BerwerthPersimmon Creek.-This is a meteoric iron of a somewhat unusualtype. It has been examined by Wirt Tassin6 and also by C. KIein.Tassin describes it as consisting of a more or less continuous metallicmatrix in which are imbedded troilite, schreibersite, and carbon : smallquantities of olivine are also found in the troilite areas. On treat-ment with dilute hydrochloric acid, sulphuretted hydrogen is evolved.Tassin has estimated the amount of this and has made analyses of thesoluble portion as well as of the schreibersite, olivine, and insolubletaenite (Fe,Ni). He classes the specimen as a granular octahedritecontaining numerous areas of troilite and some of silicate.Klein7 hasidentified rhombic and oblique pyroxenes in the dark silicate patches.He points out that this iron presents certain analogies to the ironsfrom Kodaikanal and Netschaevo, but thinks it is best placed in aclass by itself.Ranchito [ Bacubirito], Mexico.-An iron consisting mainly of fine-grained plessite.Schafstadt, Memeburg.-This is a stone of considerable interest, asas eukrite.It has been described by Cohen.8Ainer. J. Sci., 1904, 17, 383.Mitth. natww. Ver. ATc16- Yorpommern. v. Bfigen, 1904, 35, (1903), 3 ; Abstr.,Sitzungsber. K . Akad. Wiss. Berlin, 1904, 114 ; Abstr., 1904, ii, 352.J. and Proc. Boy. Soc. New South Wales, 1904, 37, 234 ; Abstr., 1904, ii, 671.Tsch. Min. Mitth., 1904, 23, 86.Proc. U.S. Il'ationn2 M u s c i w ~ , 1904, 27, 955 ; Abstr., 1904, ii, 671.Xitzimgsber.K. Akad. Wiss. B e d i i c , 1904, 572.1904, ii, 494.8 Mitth. ncrturw. Ter. ATew JTorpommes.n. v. Riiycn, 1904, 35, (19OS), 3 ; Abstr.,VOL. 1. R1904, ii, 494242 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.it has been shown by (3. Kleinl to contain leucite, a mineral nothitherto detected in meteorites. It fell in June, 1861, and its otherconstituents are anorthite, augite, glass, and ore.Ternera, Chile.-An analysis of the iron is given by K1ein.lYoke-uchi-mura, Japcc?z.-A meteoric stone. An analysis byToZuca-Mani.-E. Sommerfeldt 2 has described a specimen from theUberabcc, Minus Geraes.-E. Hussak 3 has given an account of thisWeaver Mountaiiz, A&ona.-A meteoric iron. An analysis byWillarnette, Oregon.-An octahedral iron, described by H. A.Liiidner is quoted by Klein.1Tiibingen University Collection.stone, which fell in 1903.Lindner is quoted by Klein.1Ward.*Rock Analyses.Two valuable compilations have been issued by the UnitedStates Geological Survey. The first (Professional Paper No. 28)gives a series of “Superior analyses of igneous rocks,” selectedfrom Roth’s Tabellen, 1869 to 1884, and arranged by H. S.Washington. The second, containing tables of 1672 analyses of rocksmade in the laboratory of the United States geological survey between1880 and 1903, has been compiled by F. W. Clarke5 and issued asBulletin No. 228. I n an interesting introduction to this memoir, themean composition of igneous rocks and the relative abundance oftheir constituent minerals is discussed, and the values deduced fromthe analyses tabulated. The general result arrived at is that theaverage igneous rock has very nearly metasilicate ratios and is quiteclose to an andesite in composition. The following figures give anapproximate estimate of the relative abundance of the variousminerals which enter into the composition of igneous rocks expressedin percentages : felspars, 59.5 ; hornblende and pyroxene, 16.8 ; quartz,12; biotite, 3.8; titanium minerals, 1.5; apatite, 0.6. The less frequentminerals make up the residue, 5.8 per cent.In this connection it is interesting to take note of the conclusionarrived a t by MennellG from n study of the distribution of igneousrocks in South Africa. He finds that granite so largely predominatesthat no appreciable error will be made if the average composition ofSitxstngsber. K. Ahad. Wiss. Berlin, 1904, 114, 978 ; Ab~tr., 1904, ii, 352, 572.Jnkrh. Min., 1904, ii, 118.Ann.. naturhist. Hofmu. Wieit., 1904, 19, 85 ; Abstr., 1904, ii, 746.P?.oc. 12ochesteY Acad. Sci., 1904, 4, 137.Abstr., 1904, ii, 669. 6 #cot. Mag., 1904, [v], 1, 263MINERA T,OGICAL CHEMISTRY. 243the rocks of that region is taken to be the same as the mean composi-tion of the granite. To take a mean of the values obtained onanalysis of different rock types without regarding their relativeabundance would in this case lead to quite erroneous results.I n conclusion, attention may be drawn to the “Manual of theChemical Analysis of Rocks” (pp. ix. + 183. New York : Wiley andSons; London: Chapman and Hall, Ltd., 1904) brought out byH. S. Washington. This work contains detailed instructions forcarrying out the processes best suited to the analysis of complexsilicates, and will be found invaluable by students of mineralogicalchemistry,A, HUTCHINSON,R

ISSN:0365-6217    

DOI:10.1039/AR9040100222

出版商:RSC    

年代:1904

数据来源: RSC

摘要:

RADIOACTIVITY,THE rapid growth of the science of radioactivity and the comparativenewness of the field of work which i t covers make it desirable thatthe first annual report in this section should consist of a generalr t s u d of the present position which has been attained. It is, however,impossible in the short space available to attempt to deal a t all com-prehensively with the many independent lines along which progresshas been made. Since M. Henri Becquerel made the original discoveryof radioactivity in the case of uranium in 1896, a mass of evidencehas been accumulated rapidly by both physicists and chemists, and avolume could be filled by the mere enumeration of their results. For-tunately, this need not be here attempted, for during the past yearseveral treatises have been issued which give connected accounts ofthe whole subject from the beginning.I n recent discussions, the morepurely physical aspects of radioactivity have received the greaterattention, so that prominence will here be given mainly to thechemical evidence, and especially to the discovery of radioactivechange and to the view that has been advanced that radioactivity isaccompanied by the spontaneous transmutation of the radioactivematter.It has been known from the first that radioactivity appeared to bea specific property of certain elements, and was independent of thephysical or chemical condition of the substance. Becquerel showedthat radioactivity, then defined as the power of giving out a peculiarradiation resembling the X-rays in its power of penetrating opaquematter and affecting the photographic plate, was a property commonto all the compounds of uranium and to the element itself.Mme.Curie found that the activity of various uranium compounds wasindependent of their source or previous history and could not beincreased or diminished by chemical treatment. She expressed the viewthat radioactivity was an atomic phenomenon, and later stated thatthis was the guiding principle underlying her researches. An exam-ination of all the known elements showed that only one other, thorium,was radioactive, and this to about the same extent as uranium, whenexamined by the electrical method, To the photographic platRADIOAC'I'IVITT. 245thorium is much less active than uranium, and this is now explainedby the fact that the intensity of the a-radiations, which cause thegreater part of the electrical effect, is the same in the two cases,whilst the p-rays which cause the photographic effect are relativelyfeeble in the case of thorium.An examination of the naturally occur-ring minerals showed that many of the uranium ores possessed ahigher activity than pure uranium or thorium compounds. On Mme.Curie's view of the atomic character of radioactivity, this could onlybe explained by the presence of unknown elements of great radio-activity, for i t was not to be expected that any large proportion ofnew elements could be present in such well known ores. The success-ful search for these new elements in the pitchblende of Joachimsthal,Bohemia, is well known, and attention may be merely directed here tothe striking confirmation i t afforded of Mme.Curie's principle.Urookes later succeeded in profoundly modifying the activity ofuranium by chemical treatment, thus showing that the principle hadbeen originally based on erroneous evidence. But by that time thenature of the radioactive process was beginning to be elucidated, andthe view that radioactivity is an atomic phenomenon in a modifiedand definite form still serves as the guiding principle of the investi-gator. It has served to explain and correlate the whole subject on adefinite physical basis, and has directly suggested many fruitfulresearches.I n the early stages of the search for the unknown radio-elementscausing the high activity of pitchblende, the mineral was separatedinto its constituents by the ordinary methods of chemical analysis,and the activity of each taken as the guide of the presence or absenceof the active elenients.1 I n this way, i t was found that the activematter present, after the rcmoval of the uranium, could be dividedinto three groups, the first separating with the bismuth (polonium), asecond separating with the barium (radium), and a third discoveredlater by Debierne, separating with the rare earths (actinium). Thejustification for regarding the activity of pitchblende as being due tothree distinct new elements rested a t first entirely on the differencesexhibited by the active matter in the analytical separation.Now,however, the claim is firmly based on the distinct specific character ofthe radioactivity in each case. It is difficult t o give a concise answerto the question whether actinium and polonium are to be regarded asnew elements. All the radioactive substances known exist in pitch-blende. Butin the case of one only, namely, radium, is there direct evidence of amaterial character of the specific elementary nat ure of the substance.I n the other cases, such evidence is lacking, for all exist in suchMme. Curie, Thesis reprinted from Chem News, 1903.Of the eighteen given in a table later, sixteen are new246 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.minute quantity that, apart from the radioactivity, there is no otherevidence of their existence.The radioactive evidence is, however, ofa very full and varied character, and the analogies existing betweenradium, the elementary character of which is beyond question, and theother radioactive substances, especially actinium and polonium, indicatethat the sole reason why a specific material nature has not been shownto be possessed in the other cases is that the quantities dealt withare too small to come within the range of ordinary methods ofexamination.Polonium.-Mme. Curie did not succeed in separating this substancefrom bismuth, although she effected a partial separation. Poloniumis to be identified with the radio-tellurium of Marckwald, and to thelatter we are indebted for the most definite chemical examination ofthe substance.effected the separation of polonium from bismuth, and attained to adegree of concentration of the radioactive matter far exceeding thatnecessary in the preparation of pure radium compounds. I f a plateof bismuth is immersed in a solution containing polonium, the wholeof the active matter is quickly deposited and the solution left inactive.The deposit is metallic in character and consists mainly of tellurium.A more advantageous separation may be effected by treating thesolution with stannous chloride, when the whole of the activematter is obtained as a minute, intensely active precipitate.1.5grams of the latter were obtained by Marckwald from two tons ofpitchblende. By the addition of hydrazine hydrochloride the whole ofthe tellurium was precipitated in the inactive state, the solution retain-ing the active matter.By the addition of stannous chloride, the latterwas completely precipitated, the weight obtained being only fourmilligrams. This represents a proportion of one part to five hundredmillion parts of pitchblende. The quantity was too smell to yielddefinite chemical reactions. The activity was, however, enormous. Ahundredth of a milligram excites zinc sulphide to phosphorescencesuificiently intense to be visible to a large audience. Copper andbismuth plates coated with infinitesimal quantities of polonium, butextremely active, have been for some time on the market under thename of radio tellurium. Even the most powerful preparations ofpolonium are non-luminous.The radiation consists entirely of the aor non-penetrating type. No emanation is given off and poloniumdoes not impart activity to surrounding objects.Mme. Curie observed that the activity of polonium is not permanent,but decays steadily with the lapse of time.2 The rate of decay has notyet been accurately determined, but the time taken for the activity toI n a series of remarkable investigations, MarckwaldBer., 1902, 35, 2285 and 4239 ; 1903, 36, 2662.Thesis, p. 22 (translation)RADIOACTIVITY. 247fall to half the initial value is of the order of one yem. The viewnow held is that it is probably a product of radimii-the radium E ofRutherford.Actinium.l-With this substance is to be identified the emanationsubstance or emanium described by Giesel.2 Debierne, who discoveredit in t’he rare eart,hs separated from pitchblende, showed that the bulkof the matter consisted of .thorium.Giesel succeeded in freeing hispreparations from thorium a,nd found the residue to consist mainly oflanthanum. Its radioactive properties have only recently been exactlystudied. It gives both a- and P-rays, and Debierne showed that i tgives a characteristic emanation, and imparts activity to neighbouringobjects. These facts establish the claim of actinium to be consideredas a specific type of radioactive matter. I n all probability, actiniumand polonium have each been obtained homogeneous in a radioactivesense, that is, they have been completely freed from other radioactivematter. But the proportion in which they exist in pitchblende is sominute that it is impossible to obtain a weighable quantity of either.It therefore follows that the activity must be exceedingly great, andin each case, coniparing similar weights of matter, it is probably manyhundred times the activity of pure radium. A practical difficulty inthe way of their preparation is that they are undergoing change intoinactive elements so rapidly that a limit is set on the amount that canbe accumulated.The presence of inactive matter does not interferewith the investigation of their radioactivity, and in a radioactive senseactinium and polonium are now almost as well known as radium.3Radium.-The barium obtained from pitchblende was convertedinto chloride and fractionally crystallised from water.4 By arrangingthat only a small quantity of crystals separated froin the solution, itwas found that five times as much radium separated with the crystalsas was left dissolved in the solution.By repeating this process agreat number of times, Mme. Curie isolated from one ton of pitch-blende residues (the residues left after the extraction of the uranium)a small fraction of a gram of pure radium chloride. When examinedin the spectroscope, the brightest lines of barium were barely visible.The methods of fractionation have been improved by Giesel by thesubstitution of the bromide for the chloride. Here also the radiumtends to separate with the less soluble portion, but only about eightfractionations serve to remove the greater part of the barium.TheDebierne, Compt. rend., 1899, 129, 593; 1900, 130, 906; 1903, 136, 446 andGiesel, Ber., 1902, 35, 3608 ; 1903, 36, 342 ; 1904, 37, 1696 and 3963.Compare Debierne, Compt. Tend., 1904, 138, 411 ; Miss Brooks, PhiE. Nag.,Mme. Curie, Thesis, p. 24.767.1904, [vi], 8, 382.b’er., 1902, 35, 3609248 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.yield stated by Giesel is about 0.2-0.3 gram of radium bromide froma ton of residues.So obtained, the activity is about two million times as great asthat of uranium, although a direct comparison of two activities sowidely different is probably not very exact. The best prepara-tions are but slightly luminous in the dark. The rays from afew milligrams, after penetrating an inch of steel, should produce aneffect on an ordinary X-ray screen which should be immediatelyvisible to a normally sensitive eye on completely darkening the room.This serves as a rough test of the genuineness of the product.Therays penetrating ordinary metal foil produce intense luminescence inbarium platinocyanide crystals, willemite (zinc orthosilicate), and to alesser degree in glass, paper, finger nails and many common materials.The radiations rapidly discolour glass and many salts in the same wayas the cathode rays and X-rays. Quartz also undergoes slight darken-ing by prolonged action. ‘Yellow phosphorus is converted into the redvariety, and a solution of iodoform is turned purple by the action ofthe rays. Aqueous solutions of radium were found by Giesel toevolve hydrogen and oxygen continuously in considerable quantities.Radium produces physiological effects analogous to those produced bythe X-rays.A few milligrams of radium bromide covered with thinmica and laid for a few minutes on the skin produce a painful burnwhich slowly develops and may take months to heal. The rays ofradium have been used by medical men with marked success in thetreatment of some forms of surface cancer, such as rodent ulcer, butthey seem powerless to .mitigate the ravages of deep-seated tuniours.The evidence for considering radium to be a new element is of thesame character and at least as definite as in the case of any of theolder known elements. I n the first place, the methods of fractionationemployed in its separation from barium show that it resembles thelatter element almost completely, being distinguished only in itschemical reactions by the greater insolubility of its halide salts.Theatomic weight of the element was obtained by Mme. Curie from adetermination of the percentage of chlorine in the anhydrous chloride,and found to be about 225. This agrees well with its chemicalbehaviour, for there is a vacant place in the periodic table correspond-ing with this value in the alkaline-earth family of elements. There isthus little doubt that radium is the missing heaviest representative ofthis family. Its whole behaviour conforms to this view. As in thecase of the other members, it is most easily recognised by its flameand spark spectrum reactions, giving a fine carmine coloration to theBunsen flame, and a most characteristic series of new lines in its sparkspectrum.It was by the latter test that the first indication of itsThesis, p. 26RADIOACTIVITY. 249presence, independently of the high radioactivity of preparations con-taining it, was obtained. The spectrum of radium has been studiedexhaustively by Demarqay, Runge,’ and Crookes,2 the latter extendingour knowledge into the ultra-violet region. The results of Runge andPrecht 3 are highly interesting, for they examined the spectrum in amagnetic field in the same way as Runge had previously examined thespectra of the other alkaline-earth elements. Under these condit’ions,the spectrum may be analysed into several groups or “series,” themembers of the same series being resolved into components by theaction of the magnetic field in a similar way.I n this way, the lines ofdifferent series may be distinguished from one another. Theyseparated the spectrum of radium into three separate series, whichare exactly analogous in charaoter to those previously distinguished inthe case of calcium, barium, and strontium. By making use of anempirical relation, which has been found to hold for the other membersof the family, connecting the constant diikrence in wave frequencybetween the individual lines of the same series and the atomic weightof the element, they deduced from tho known values in the case ofcalcium, barium, and strontium the value 258 for the atomic weightof radium.This result is probably more reliable than that obtained,also from spectroscopic considerations, at about the same time byMarshall Watts.4 The value obtained by this investigator agrees wellwith Mme. Curie7s number, but according to Runge i t was obtainedby comparing together lines in different series. The discrepancybetween the chemical and Runge’s spectroscopic value for the atomicweight is of importance as it raises the question whether radiumpossesses a heavier or lighter atom than uranium. The higher numbergives radium the heaviest atom known, whereas there are grounds forbelieving that radium is a product of uranium. The balance of allthe evidence at the present time seems to be in favour of Mme. Curie’svalue. The well-defined material properties of radium, and especiallythe spectroscopic evidence, show that radium is as distinct and definiteit type of elementary matter as any of the older known elements, andfurnish a sufficient answer to the suggestion that radium is a compound,using that term in its ordinary chemical significance.The property of radioactivity furnishes a new weapon for the detec-tion of almost infinitesimal quantities of matter, and in this respect isalmost incomparably more delicate than the spectroscope. Uemarqayclassed radium as an element giving an exceedingly delicate spectrumreaction, one part of radium being capable of detection by the spectro-scope when mixed with 10,000 parts of barium.On the other hand,Ann. Physik., 1903, [iv], 10, 655, and 12, 407.Proc.Roy. Soc., 1903, 72, 295.:: Phil. May., 1903, [vi], 5, 476. I b i d . , 6, 64250 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.by the radioactive test, using the characteristic radium emanation, farsmaller proportions can be measured. I n recent experiments, theauthor has measured the amount of radium mixed with 1013 times thequantity of uranium, when the actual amount of radium was belowThe present refined methods of investigation, introduced by Ruther-ford, have shown that no two of the known radio-elements exhibit thesame kind of radioactivity, so that it is possible to distinguishuranium, thorium, radium, polonium, or actinium from one another bytheir radioactivity, eve11 when they are only present in excessivelyminute quantity.Hence the activity of any two or more of theseelements cannot be due to the presence of a common constituent. Theelectrical methods of measurement are capable of great range, accuracy,and rapidity, and have, except in special cases, almost entirelyreplaced the older photographic method by which Becquerel origin-ally discovered the uranium radiation. They depend on the factthat the newly-discovered type9 of radiation, the X-rays cathode rays,and the Q-, p-, and y-rays of the radio-elements possess in common thepower of converting, for the time being, the gases through which theypass into partial conductors of electricity. The conduction of elec-tricity through gases exposed to the X-rays was shown by J. J.Thomsonl to be effected by a similar mechanism to that obtaining inliquid electrolysis. The current is conveyed by the convection ofoppositely charged molecules or ions to the respective electrodes.Butthere is a well-marked distinction. Electrolytes are now regarded asexisting in a permanently ionised condition, and even in the caseof very non-conducting liquids the number of ions present, whetherthe current is acting or not, is always very great compared to thenumber discharged in unit time a t the electrode. Hence electrolytesobey Ohm’s law. In the case of gases screened from the action ofionising radiations it is probable that no ions exist. The ionising raysproduce the ions throughout the volume of the gas in very limitednumbers, the number produced in unit time being a measure ofthe intensity of the radiation absorbed by the gas. Hence conductinggases do not obey Ohm’s law, but above a certain critical difference ofpotential between the two electrodes, known as the “ saturatingvoltage,” the current flowing is independent of the voltage.Owing tothe small viscosity of the gas cornpared with that of a liquid, themovement of the ions is much more rapid in gases, and is of the orderof 1 cm. per second for unit potential gradient in air. When theionising agency is withdrawn, the oppositely charged gaseous ionsrapidly recombine, and the gas again assumes the non-conductingstate. The tendency towards recombination always exists. The1 Conduction of Electricity through Gases, 1903.gramRADIOACTIVITY.251maximum current capable of flowing through a gas, known as the“saturation current,” serves as an accurate measure of the num-ber of ions produced in unit time, and is proportional to theamount of radiation absorbed by the gas. It may be definedas the current flowing when all the ions present give up theircharges to the electrodes, the proportion recombining in the volume ofthe gas before reaching the electrodes being inappreciable. Inpractice, for weak radioactive preparations, under the conditionsordinarily employed, 300 volts serves to produce the saturationcurrent.The current is usually measured by means of a quadrant electro-meter, Very feeble currents are measured by the rate of discharge ofa gold-leaf electroscope.The currents produced by active radiumpreparations may be measured by means of a sensitive galvanometer.M. Curie uses a special method of measurement, in which the electro-meter is used as an indicator, the current flowing through the gasbeing balanced by an exactly equal and opposite current produced bytension of a lamina cut from a quartz crystal. This has all the advan-tages of a null method, and is independent of the sensitiveness of theelectrometer.Professor J. J. Thomson’s theory of gaseous conduction was shownto apply without niodification to the ionisation effected by the rays ofuranium and the other radio-e1ements.l I n this research, Rutherfordanalysed the radiation of uranium into two types, the a-radiation, whichproduces by far the greater part of the ionisation, and is absorbed bya single sheet of ordinary paper, and a /3-radiation producing relativelyfeeble ionisation, but capable of traversing a thickness of severalmillimetres of aluminium, copper, glass, &c., before being completelyabsorbed.This method of analysing the complex radiations given outby the radio-elements, by the successive absorption of the less pene-trating types, has been widely used in the case of the other radio-elements, and forms one of the two main methods used for thispurpose. The other depends on the effect of an electric and of amagnetic field on the path of the ray. Both methods agree indistinguishing three distinct classes of rays, the U- and p-rays alreadymentioned and a third relatively unimportant type called the y-rays.y-Rays.-These are characterised by their extraordinary power ofpenetration. According to the measurements of Rutherford,Z 1 percent.of the y-rays survive absorption after penetrating 7 cm. of lead,19 cm. of iron, or 150 em. of water. The y-rays from uranium andthorium are hardly detectable unless large quantities of these sub-stances are examined. Those from radium are fairly prominent, bothRutherford, P l d . Mag. 1899, [v], 47, 109.Aktture, 1902, 66, 315252 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.by their photographic and fluorescence effects. Their ionising power isrelatively feeble, owing to the slight extent to which they are absorbedby gases. They are not deviated by the most powerful electric ormagnetic fields, and in this they resemble the X-rays.Although consider-able differences exist between ordinary X-rays and the 7-rays in theirrelative powers of ionising different gases, A. S. Eve 1 has shown thatthe latter are similar in these respects to the most penetrating X-raysthat can be produceJ. Rutherford has shown that the production ofthe 7-ray is causally connected with the expulsion of the P-particle, thetwo types of radiation always being proportional to one another. Theview2 is now generally held that the y-ray stands in the same ora similar relation to the @-ray as the X-ray stands to the cathode ray.The main difference is that the 7-rays are produced by the suddenpositive accelera!ion of the electron which constitutes the P-radiantparticle, whereas the X-rays are produced by the far less suddennegative acceleration undergone by the cathode radiant particle oncollision with the anticathode of the X-ray bulb. The much greaterpenetrative power of the y-ray is simply explained by the far greateracceleration experienced by the electron in the disintegration of theatom than can be effected by any artificial process.I t producesrelatively small ionisation, but powerful fluorescence and photographicaction.The author has shown3 that the whole of the photographiceffect of uranium is due to the P-rays alone. The phosphorescence ofthe platinocyanides, willemite, and kunzite in ordinary circumstancesis mainly due to the P-rays. On the other hand, zinc sulphide is butlittle affected by this type.The P-rays were identified early with the cathode rays, or radiantmatter of Sir William Crookes, for they readily suffer deviation byelectrostatic and magnetic fields in the same sense as the cathode ray,although not nearly so readily as the latter.The views heldoriginally by Crookes of the corpuscular nature of the cathoderadiation have been proved and extended by J. J. Thomson, and thelatter’s well-known theory4 with regard to their nature is nowuniversally accepted by physicists. By simultaneous measurements ofthe electrostatic and magnetic deviation suffered by the cathoderadiant particle, Thomson deduced their velocity and ratio elm, of thecharge e to the mass m. The velocity increases with the degree ofexhaustion of the Crookes tube, and for high exhaustion averagesone-tenth, and may attain one-third of the speed of light.The ratioP-Rays.-This type was at first the most studied.Phil. Mag., 1904, [vi], 8, 610.Rutherford, Natzwe, 1904, 69, 436.Trans, 1902, 81, 1860.Conduction of Electricity through Gases, 1903RADIOACTIVITY. 253elm, on the other hand, is invariable, being independent of thevelocity, the nature of the material of which the cathode is made, thenature of the gas present in the tube, and the manner in whichthe cathode rays are produced. Thus the same value was obtained forthe cathode rays expelled from a negatively-charged polished zinc sur-face in vacu.0 under the influence of ultra-violet light. This ratio wasfound to be one thousand times greater than in the case of the hydro-gen ion of electrolysis, and therefore a thousand times greater thanin any case previously observed, I f ultra-violet light falls on zinc ina gas under atmospheric pressure, the ordinary negative ions of gaseousconduction are expelled. The charge carried by the individual ion hasbeen directly determined and shown to be the invariable “atomic charge”carried in every case by the gaseous ion, and equal to that carried bythe univalent ion in electrolysis. By diminution of the pressure of thegas, the free path of the expelled negative ion is increased, until a thigh exhaustions it is free to move under the action of the electricfield, and then becomes a cathode ray particle.Hence, unless thecharge suffers subdivision in this process to one-thousandth of itsinitial value, which on the atomic view of electricity now prevalent ishardly conceivable, it follows that the mas3 of the cathode radiantparticle must be only one-thousandth of the mass of the hydrogen ion.The view now held is that the cathode radiant particle constitutes asingle electron or atomic charge travelling free and unassociated withmatter.Becquerell found that the ratio elm of the p-radiant particle fromradium and uranium is the same as in the other cases referred to.Thevelocity is in general far higher. The p-rays of uranium travel atabout two-thirds the velocity of light, whilst in radium the velocityvaries over a considerable range, but Kaufmann 2 has shown that themost penetrating p-rays of radium possess a velocity of 95 per cent.ofthat of light. Becquerel had shown previously that the least penetrat-ing rays are the easiest to deflect and possess the lowest velocity. Thedirect proof that the @rays transport negative electricity was obtainedby M. and Mme. Curie, who showed that an insulated metal plate inthe path of the /?-rays of radium acquires a negative charge, althoughthe rays were first made to traverse a sheet of thin metal connected toearth. The same effect has been shown in the simplest manner byS t r ~ t t , ~ whose apparatus is well known.a-Rays. -These are distinguished by feeble penetrative power, feeblephotographic effect, but very great ionising power. The latter is con-nected with their almost complete absorption by a few centimetres of air.Their phosphorescent effects are small in the case of those substancesThis view will be alluded to later.Compt.rend., 1900, 130, 809.Phil. Mag., 1903, [vi], 6, 588.Ibid., 1902, 135, 577254 ANNUAL REPOKTS ON THE PROGRESS OF CHEMISTRY.which show tlie @-radiation well, but very great in the case of Sidot’shexagonal blende (phosphorescent zinc sulphide). It was discoveredsimultaneously by Sir William Crookes and by Elster and Geitel thatthe phosphorescence of zinc sulphide under the a-radiations, whenresolved by a lens, consists of momentary flashes or scintillations. Itis of interest to record that Elster and Geitel discovered this propertyfor the radioactive matter separated from the atmosphere.1 The well-known instrument designed by Crookes and known as the spinthariscopeillustrates this effect in a simple manner.It is probable that each flashof light corresponds to an impact of the individual a-particle, so thatthe instrument may be said to render visible to the eye the effect of asingle atom of matter. This thought brings out vividly the new rela-tions between energy and matter which radioactivity has revealed.When i t is considered that the quantity of radium used in the con-struction of the spinthariscope is probably quite unweighable, and thatthe effect persists over years without diminution (although the phos-phorescent screen may need renewal), some idea may be obtained of thedelicacy of the radioactive methods of investigation.Rutherford recognised at a very early stage the preponderatingimportance of the a-rays, and showed that in all cases they representedby far the greater part of the total energy radiated.This view hasreceived repeated confirmation. The nature of the a-rays for a longtime remained unsettled, and they were at first thought to be theX-rays resulting from the expulsion of the @-rays. This view wasadvocated by Becquerel, but it is now known that the a- and P-radiationsare quite unconnected.2It has been shown that the two rays occur at quite different stagesof the radioactive process, so that in the case of uranium it is possibleto separate all the P-radiating matter from that giving the a-radiations.The nature of the a-rays was elucidated by Rutherford,3 who succeededafter many failures in establishing that they undergo a slight butperceptible deviation by very intense electrostatic and magnetic fields.The deviation is in the opposite sense to the cathode-ray, and Ruther-ford concluded that the a-radiation, like the P-radiation, consists in theflight of discrete charged particles, which carry a positive instead of anegative charge.The idea, however, that the two processes are in anyway complementary to one another does not bear criticism, for it isknown that in most cases several a-particles are expelled from the atombefore the P-particle is expelled.Using reasoning similar to that originated by Thomson, RutherfordThe radioactivity of the atmosphere seems to be derived from a niinute amountThe latter appears frequently to con-Phil.Mag., 1903, [vi], 5, 177.of radium emanation diffusing from the soil.tain infinitesimal quantities of radium.Soddy, Tmns., 1902, 81, 1860RADIOACTIVITY. 255deduced the value of the velocity of the a-particle to be about one-tenthof the speed of light, and the ratio elm to be over one thousand timessmaller than in the case of the P-particle. Making the assumptionthat the charge carried by the a-particle is the same as that carried bythe univalent ion, Rutherford deduced the mass of the particle to be1.6 times the mass of the hydrogen atom. The deviation has beenconfirmed by Becquere1,l who showed also that the a-ray of polonium issimilarly deviated.Recent developments have caused Rutherford toconsider i t probable that the a-particle is or becomes an atom ofhelium.New results have gone to show that there is still much to beexplained with regard to the nature of the a-ray, for it seems provedthat the a-particle at the moment of its expulsion is uncharged, butgains a positive charge by passage through che gas. This resulttranspired in consequence of the failure of all attempts to detect thepositive charge carried by the a-rays by direct methods similar to thosedescribed for the case of the P-rays. On amount of the easy absorptionof the rays, and the need to avoid ionisation, it was necessary toperform the experiments in a very high vacuum. Wien,2 working inthis manner, showed that a plate exposed to the a-rays did not gain apositive charge, and Rutherford 3 has recently obtained the same result.On the other hand, it has been deduced from theoretical considerationsby Bragg,* that even if the a-particle started on its course through agaseous atmosphere uncharged it must immediately lose an electron bypassage through the atom of the gas molecule, and so gain a positivecharge.Ionisation is usually regarded as being due to the detachmentof an electron from the atom of the gas molecule struck by the radiantparticle. There is a fundamental difference, however, between theionisation produced by a radiant electron or ,@ray, and by a radiantatom or a-ray. I n the latter case there is just as much reason foran electrically neutral a-radiant particle to suffer the loss of anelectron and become positively charged as there is for the electricallyneutral atom of the gas molecule struck by the a-particle.Inother words, in the case of two colliding atoms, the ionisationmust be mutual, for, so far as their relative niotion is considered,either niight be regarded as the radiant particle. This view,although only barely referred to in the paper quoted, is of con-siderable importance. The author5 has drawn attention to thedifficulty of explaining, on the current ideas with regard to the con-Cowapt. rend., 1903, 136, 199, 431, 1517.Plrysikalische ;Teitschrif, 1903, 4, 624.Bakcrian Lecture, Phi?. Traits., 1904, A204, 213.Phil. Mag., 1604, [vi], 8, 721.Radioactivity, 1904, p.180256 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.servation of opposite electric charges, the fact that the residue leftfrom the electrically neutral atom on the expulsion of the positivelycharged a-particle is left positively charged (compare p. 258). OnProfessor Bragg’s view, the positive charge in both cases is acquiredafter the disintegration, the recoil of the residue being considered tohave the same effect as expulsion in the case of the radiant particle.Two consequences immediately follow : (1) in a perfect vacuum, theexcited activity should not be concentrated on the negative electrode inan electric field. This fact has been observed by Rutherford 1 experi-mentally, but no explanation has before been given ; (2) the a-particlein a vacuum should undergo neither electrostatic nor magnetic deviation.Des Coudres 2 has measured the electrostatic and magnetic deviationof the a-particle by Becquerel’s photographic method in very highvacua, and has obtained identical results with those obtained byRutherford, who worked in hydrogen under atmospheric pressure, bythe electrical method.There is thus need for a careful re-examinationof this question, for there is strong probability in favour of the viewthat the a-particle is initially uncharged, but gains its charge by theordinary mechanism of ionisation. A further important advance in ourknowledge of the a-rays of radium has been made by Bragg, and willbe referred to after the subject of radioactive change has been con-sidered.Types of Temporarily Radioactive Matter.-The view that radio-activity is an atomic property necessitates, on the older view of theunchangeability of the atom, that the activity should be in all cases apermanent property of the matter exhibiting it.This is, however,far from being the case, for it is now known that in many of the casesof radioactivity, in addition to the expulsion of a- and P-particles, thereis a simultaneous production of new types of matter possessing tempor-ary radioactivity. The first of these to be discovered was the thoriumemanation. Rutherford,3 by the aid of the electrical method of investiga-tion, found that the compounds of thorium differ from those of uraniumin that they not only emit a- and P-rays, but also that they communicateto the surrounding atmo3phere the property of temporary radioactivity.The air in the immediate neighbourhood of a thorium compound itselfemits a-rays of a kind similar t o those emitted by the thoriumcompound directly. For some minutes after removal, the air retainsits radioactivity, but the latter continuously diminishes in a geometricalprogression with the time.At the end of each minute interval, theactivity is only one-half as great as at the beginning of the interval, sothat in ten minutes the activity of the air is only one-thousandth ofRadioactivity, 1904, p. 282.Physikidische Zeitschrijl, 1903, 4, 483.Phil. Mag., 1900, [v], 49, 1RADIOACTIVITY. 257the initial, and may be neglected for practical purposes. If thethorium compound is wrapped in porous materials such as paper orthin metal leaf, the same effect is observed, but the thinnest sheet ofmica, or other substance completely impervious to the passage of a gas,entirely prevents it, and the outside air shows no trace of self-radio-activity.Rutherford concluded that an actual material substance or‘‘ emanation ” was given off by thorium compounds, and this emanationpossessed the power of diffusing like a gas. Later work has establishedthe view, and shown that the radioactive emanations given off bythorium, radium, and actinium are radioactive gases of high molecularweight, present in such minute amount that the radioactivity is usuallythe only indication of their existence. All thorium compounds showthis property, but in widely varying degrees, the emanating power othorium oxide being much diminished by strong ignition.But theemanation always presents the same characteristics, and its radio-activity decays a t the same rate under all conditions so far investi-gated. I f the course of decay is represented by the equationwhere It is the activity after time t in seconds and I,., the initialactivity, e being the base of natural logarithms, and X a constant, itbecomes general for all types of temporarily radioactive matter known.But the constant X varies widely in the different cases and has receivedthe special name of the radioactive constant. Thus for the thoriumemanation it ha8 a value of 1/87’, when t is expressed in seconds. Theradioactive constant is the most characteristic feature of a temporarilyactive type of matter, and serves well for its differentiation.Accordingto the disintegration theory, it represents the fraction of the wholeundergoing change per second, and the reciprocal 1 / X represents theaverage life of the changing atom in seconds.Radium and actinium both give radioactive emanations, but uraniumand polonium do not. The radium emanation loses its activity muchless rapidly than that from thorium, but the course of decay followsthe geometrical law given. The value of X is here about 0*000002,1the activity falling to half the initial value every four days. The valueof l / X is 5.3 days. The actinium emanation, on the other hand, is evenshorter lived than that from thorium, the value of X being 0.17,according to Debierne.The three elements giving radioactive emanations are the only onespossessing the muchdiscussed property of inducing or exciting radio-activity in surrounding objects, or, to speak more accurately, ofCurie, Compt.rend., 1902, 135, 857 ; Rutherford and Soddy, Phil. Mag., 1903,[vi], 5, 455.VOL. I. 258 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.imparting radioactivity to surrounding objects. This property wasdiscovered in t,he case of thorium by Rutherford,l and at once correctlyascribed by him to the action of the emanation, and by M. and Mme.Curie 2 in the case of radium, and ascribed by Becquerel to a pheno-menon analogous in nature to phosphorescence. Rutherford submittedthe thorium-excited activity to a careful investigation.He showedthat only those substances were rendered active by thorium which hadeome into immediate contact with the thorium emanation, and that theintensity of the radioactivity of the substance rendered active wasproportional to the intensity of the radioactivity of the emanation inwhich it had been immersed. He showed that on removing the substancerendered active from the action of the emanation, the activity decayedin a geometrical progression with the time, falling to half the initialvalue in about 11 hours, and finally completely disappearing. The radia-tion from the substance rendered active consisted of both U- and /%raysof a similar kind to those given by the thorium directly, and was com-pletely independent of the nature of the matter of which the objectrendered active was composed.Moreover, it could be removed fromthe latter by scrubbing the surface with sand-paper and by the actionof some acids. I n neither case was the activity at all destroyed, butmerely transferred to the sand-paper or acid. I n the latter case, if theacid were evaporated, the activity remained on the dish used. Theactivity decayed a t the same rate in the acid as on the substanceoriginally rendered active. Rutherford concluded that, as in the caseof the emanation, the radioactivity was caused by minute amounts ofmatter, which in this case were deposited from the emanation as a thinand invisible film over the surface of the substance rendered active.He made the further important observation that in an electric fieldthe excited activity produced by both the thorium and the radiumemanation was entirely concentrated on the negative electrode andtherefore was positively charged, By using a thin platinum wire for thenegative electrode and making the rest of the containing vessel thepositive electrode, he succeeded in making the wire intensely active.But no visible deposit was observed on the wire when examined undera high power microscope, and no gain of weight could be detected by asensitive balance.He found that when the pressure of the atmos-phere was diminished below 10 mm. the whole of the excited activitywas not deposited on the electrode, while under 0-1 mm. pressurethe amount deposited on the negative electrode was small.Anexplanation of this result has already been suggested (p. 256).Becquere1,s to explain the excited or induced activity produced byradium, proposed the hypothesis of radioactive induction, which hePhil. Mug., 1900, [v], 49, 161. Compt. rend., 1899, 129, 823.8 Bid., 1901, 133, 977RADIOACTIVITY. 259also employed to explain other cases of temporary radioactivity.According to this view, the radioactivity is induced in the originallyinactive matter-the gas in the case of the emanation, the solid matterin the neighbourhood in the case of the excited or induced activity-by the radiations of the original radio-element, much in the samemanner as phosphorescence is induced by exposure to light radiations.This view has been disproved by direct experiment.The radiationsof the original radio-element do not cause any kind of matter tobecome radioactive. Exception must be made here in the case of anobservation recorded by Sir William Ramsay and Cooke,l who found thatthe inside of a glass surface was rendered feebly active by exposure tothe P-rays of radium. But the effect was very feeble, and of an entirelydifferent order of magnitude to those dealt with in the case now con-sidered. It has been established that the ordinary induced or excitedactivity of the three elements is only produced under conditions whichallow of the direct transference of the radioactive emanation from theelement to the substance rendered active. From the point of view ofchemistry, the recognition of the material nature of the emanationsand the other examples of temporary radioactivity possesses animportance that can hardly be over-estimated.A closer investigation of the chemical and physical nature of theemanations was carried out by Rutherford and Soddy.2 The emana-tions from radium and thorium may be led in tubes containing themost powerful reagents at high temperature, such as platinum black,copper oxide, zinc dust, without being absorbed or their activitysensibly affected by the process.The conclusion was drawn that theemanations were gases allied in nature to the members of the argonfamily and possessing the same power of resisting chemical combina-tion as the latter. This conclusion was endorsed by Sir WilliamRamsay after some experiments conducted in conjunction with theauthor,3 in which the radium emanation mixed with oxygen wassubjected to prolonged sparking over caustic potash and mixed withair to prolonged contact with a heated mixture of magnesium andlime.In neither case was the emanation appreciably absorbed orthe activity altered.The discovery by Rutherford and Soddy that at low temperatureboth emanations are ~ondensed,~ and again assume the volatile formwhen the temperature is allowed to rise, finally established the materialnature of the emanations beyond question. At -154*, the radium emantr-tion condenses very sharply and completely, and is again volatilisedcompletely if the temperature is allowed to rise only one or two degrees.Xakre, 1904, 70, 341.Proc.Boy. Xoe., 1903, 72, 204.Proc., 1903, 18, 219 ; Phil. Mag., 1903, [vij, 5, 561.Trans., 1902, 81, 342.s 260 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Since pure radium compounds have become available, it is possible toobtain fluorescence effects with the emanation of sufficient magnitudeto be plainly visible to large audiences, and the gaseous nature of theradium emanation, its passage through tubes, and condensation at thetemperature of liquid air may be made the subject of many simple andstriking lecture experiments. The condensation on fragments of willem-ito contained in a U-tube immersed in liquid air, according to themethod originally employed by Rutherford, is an especially beautifulexperiment.This property has also been of the greatest service inthe isolation of the radium emanation in a pure state, with veryfruitful results.Although uranium does not give an emanation, i t gives a temporarilyradioactive type of matter which, except that it is not volatile at the ordi-nary temperature, and therefore must be separated by chemical methods,is very similar to the emanations from a radioactive point of view. SirWilliam Crookes found 1 that if crystallised uranium nitrate weredissolved in ether and the aqueous layer separated from the ethereallayer, the uranium oxide obtained from the latter was almost com-pletely inactive to the photographic plate, whereas the relatively smallquantity of uranium oxide obtained from the aqueous solution wasintensely active to the photogra4phic plate.Or, if ammonium carbonateis added to an aqueous solution of a uranium compound in excess sothat the uranium carbonate is redissolved, the very small precipitatethat is obtained on filtration possesses all the photographic activity ofthe original uranium, and, weight for weight, may be many thousandtimes as active as the latter. The uranium obtained from the solutionis again completely inactive to the photographic plate. Crookes con-cluded that he had separated an active constituent responsible for thewhole of the radioactivity of the uranium, and named it Uranium X.Becquerel 2 independently obtained similar results, but made inaddition the important observation that if the preparations were keptfor a year the uranium completely regained its lost activity, whilethe uranium X completely lost its activity.These results he soughtto explain by the hypothesis of radioactive induction already men-tioned.The author in a re-examination of these facts3 found that by themethods of Crookes and Becquerel only the @-radioactivity of uraniumhad been separated. The preparations which Crookes, using only thephotographic method, described as inactive were found to possess anearly normal activity when tested by the electrical method, whereasthe preparations of uranium X which were intensely active to the1 Proc. Roy. Soc., 1900, 66, 409.Compt. rc.nd., 1900, 131, 137 ; 1901, 133, 977.Trans., 190'2, 81, 860RADIOACTIVITY. 261photographic plate are only feebly active when examined by theelectrical method.The processes of decay and recovery described byBecquerel refer only to the /?-radioactivity. So far as is a t presentknown the whole of the a-radioactivity is a specific or atomic propertyof the uranium.Simultaneously with the work on uranium, Rutherford and Soddysubmitted the radioactivity of thorium to a careful chemical investiga-tion. It was found that if a solution of thorium was precipitated byammonium hydroxide, the thorium hydroxide was obtained very muchless radioactive than before. By this method, tlie whole of the /?-radio-activity may be removed and the a-radioactivity reduced to 25 percent. of the normal. Moreover, the thorium hydroxide so obtained,whether examined in the solid state or in solution, possesses no ernan-ating power a t all.If the solution from which the thorium had beenprecipitated was examined, it was found to possess the whole of theemanating power possessed originally by the thorium. When evapor-ated to dryness, and the ammonium salts expelled by ignition, aminute residue only was left, but this possessed in concentrated formall the radioactivity which the thorium had lost in the process. Thusi t gave P-radiation equal in amount and a-radiation t o the extent of7 5 per cent. of that given originally by the thorium preparation.The active constituent thus separated was named thorium X. Thenit was found that the radioactivity of thorium X after separationrapidly decayed with time, and with the radioactivity the emanatingpower dimished correspondingly.Both processes followed the geo-inetrical law of decay and proceeded at the same rate, both the eman-ating power and the radioactivity decaying to half the initial valueafter the lapse of 4 days. Concomitantly the thorium hydroxide, whichwhen first precipitated possesses no emanating power, no /?-activity,and 25 per cent. of its normal a-activity, gradually recovered both itsradioactivity and emanating power, and after the lapse of three weekswits normal in every respect. The simple law was followed that thesum of the various activities of the two preparations was at all timesequal to the activity of the tliorium salt initially. Rutherford andSoddy obtained similar results in the case of uranium.2 During thecourse of the decay of the /3-activity of uranium X and the recoveryof the P-activity by the uranium, the sum of the two activities is aconstant.But here the rate of change is much slower than in thecase of thorium. The activity of uranium X decays to half its initialvalue in about 38 days.It was found that if tlie uranium and thorium preparations whichhad recovered their lost activity were again subjected to the sameTram., 1902, 81, 321, 837 ; Phil. Mccy., 1902, [vi], 4, 3 i 8 , 569.i%7. Mag., 1903, [vi], 5, 441262 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.process as at first, new amounts of thorium X and uranium X wereobtained, and this process can be repeated an indefinite number oftimes with the same preparation.On the other hand, if the processesof separation follow one another without pause, no further amount ofthe active products can be separated after the first amount.The evidence in favour of regarding thorium X and uranium X asnew specific types of matter in too small quantity to be detectedexcept by their activity is as strong as in the case of the radioactiveemanations, or in the case of polonium or actinium. Each possessesa well-defined behaviour. Thus the separation of thorium X fromthorium can only be effected if ammonium hydroxide is used as theprecipitant. If sodium hydroxide or ammonium carbonate or oxalateis employed to precipitate the thorium, no separation is effected, theprecipitated thorium is in its normally active state, and the filtratecontains no radioactive matter.The behaviour is not therefore toba ascribed to the mere process of precipitation, but can only have achemical explanation, namely, that part of the activity of thorium is dueto the presence of a non-thorium type of matter, differing from thoriumin chemical nature and so capable of separation. The actual amountis, as in the case of the emanations, so minute that it can only bedetected by means of its radioactivity. From these results, Rutherfordand Soddy advanced the view that there is a continuous productionof uranium X and thorium X from uranium and thorium. It wasfound that the rate of decay of the activity of uranium X andthorium X was completely independent of temperature and of chemicaltreatment.The activity of these substances must be regarded asalways decaying at the same rate whether they are separated from theelement producing them or not. The constancy of the radioactivityof uranium and thorium is thus only apparent and is due to theequilibrium between two opposed processes. After separation, theactivity of the thorium increases until the increase of activity due tothe steady production of fresh thorium X is balanced by the decayof the activity of that already formed. This state has been termedradioactivs equilibrium. When attained, the activity appears to beconstant and permanent. The chemical separation thus only revealsthe dual character of the radioactive process without in any wayinterfering with its course.The effect of various conditions on the radioactive process hasbeen studied in many cases, but most completely for the radio-active emanations of radium and thorium.1 These lose their activityat the same rate at a red heat as at the temperature of liquid air, andare unaffected by chemical treatment. Rutherford and Soddy con-' Curie, Compt.rend., 1902, 135, 857 ; ltutherford and Soddy, Phil. Mag., 1903,[vi], 5, 561RADIOACTIVITY. 263cluded 1 that the continuous production of thorium X from thoriumand of uranium X from uranium is due to the change of the uraniumor thorium atom, for the rate of production depends only on thequantity of element, and if it were merely a molecular change it shouldbe dependent on molecular conditions.It is impossible by chemical processes to remove entirely theactivity from either thorium, uranium, or radium.A non-separableactivity always remains, and in each case consists only of a-rays. Thewhole of the a-radiation of uranium, and 25 per cent. in the other twocases, constitutes the non-separable activity. The radioactivity of theseelements therefore consists of two atomic phenomena simultaneously oc-curring. It is now known that this holds true in all cases. For just as thenon-separable activity of thorium occurs with the production of thoriumX, the activity of the latter and the production of the emanation areconnected, the power of producing an emanation not being possessedby thorium, but only by thorium X. I n the next stage, the activity ofthe emanation is associated with the production of the matter, oftenreferred to as the “active deposit,” which is the cause of the excitedactivity.From the fact that the two processes are always proportional,i t was deduced that the change of the atom into the new atomwas accompanied by the expulsion of the radiant particle. It is,in addition, a sufficient explanation of the cause of the change, for ongenerally accepted chemical ideas the expulsion of a mass of the sizeof the a-particle from an atom would have the effect of completelyaltering its chemical nature, and would be of a sufficiently fundamentalcharacter to account for the complete transformation which the matterundergoes in its passage from thorium into thorium X, from the latterinto the inert gaseous emanation, and then back again into a non-volatile form.This view derives great support from a consideration ofthe physical interpretation to be put on the geometrical decreaseof the activity in the case of the intermediate or transition forms pro-duced in the series of changes. I n the original change, so smalla fraction of the thorium changes in unit time that the quantity is notappreciably diminished. Hence the changing fraction remains aconstant definite quantity, and the number of radiant particlesexpelled in unit time, or the non-separable activity, and also thenumber of new thorium X atoms produced remains constant. This,however, carries with it the necessary consequence that the actualnumber of thorium X atoms formed in any period of observation mustbe practically infinitesimal, and far below direct methods of investiga-tion.But the only condition for its detection by radioactive methodsis that a sufficient number of a-particles must be expelled in unit time.It is probable from considerations mentioned in connection withRadioactive Change, Phil. Alng., 1903, [vi], 5, 576264 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the spinthariscope that a very small number can be detected, butsince the total quantity is practically infinitesimal, even a smallnumber must represent a finite fraction of the total. Hence theamount present must appreciably diminish, and the activity ofthorium X will decay with the time, and, proportionately, the produc-tion of emanation will diminish.It is well known that the character of a chemical change can bededuced from a study of the rate of change.Thus Wilhelmy showedthat in the case of a unimolecular reaction the amount of changingsubstance present diminishes in a geometrical progression with thetime. This is also the law of radioactive change, for the radioactivityis a direct measure of the number of atoms changing, and of the pro-portion remaining unchanged. For the so-called permanently radio-active elements, the rate of change is merely too slow to be detectedover a short period. Radioactive change is therefore a mono-systemchange, in which the atom expels a radiant particle, and so undergoesdisintegration.This theoretical interpretation of the experimental results, by whicha definite physical conception of each of the stages of the radioactiveprocess is gained, has been justified by its results.Although at thetime it was put forward it might have been regarded as somewhatrevolutionary, the subsequent developments have been so remarkablethat it would probably now be admitted that the disintegration theoryoffers an intelligible explanation of the known facts with surprisinglylittle extension of the accepted views on which the physical scienceshave been based.The disintegration series in the case of radium resembles that ofthorium closely, except that here there is no intermediate productcorresponding to thorium X.l The radium atom changes directly intothe emanation.For solid compounds of both radium and thorium, butespecially in the case of the former, the amount of emanation evolved isa very variable quantity, depending on the state of dryness of thecompound, the humidity of the atmosphere, the nature and physicalcondition of the compound, the temperature, and other conditions. Butaccording to the disintegration theory the amount of emanation shoulddepend only on the quantity of the parent element present. Thisrequirement is in fact fulfilled. The variability of t'he emanating powerobserved is merely caused by alterations in the rate of escape of theemanation from the compound into the surrounding atmosphere. If theemanation does not escape into the air, it is found to be present storedup or occluded in the compound, and may be readily obtained from itby heat, or better by dissolving the compound in water.It is foundthat the emanations escape freely from solutions and show no tendency1 Rutherford and Soddy, PhiE. Mag., 1903, [vi], 5, 460RADIOACTIVITY. 265to remain occluded. Owing to the comparatively slow rate at whichthe activity of the emanation from radium decays, it tends to accumu-late to a marked extent in dry solid preparations, and is instan-taneously released into the gas when these are dissolved. This isthe explanation of the fact first observed by Giese1,l that the activityof radium compounds steadily increases from the time of their prepara-tion, and attains a maximum three to four weeks afterwards nearly fourtimes as great as a t first.The activity of radium compounds newlyobtained from solution is the non-separable act,ivity, since in solutionthe emanation readily escapes and carries with it the power of produc-ing the excited activity. The non-separable activity of radium, as inthe case of thorium, consists of only 25 per cent. of the a-radiations.On keeping in the solid state, the emanation is reproduced and stored upwithin the solid compound until equilibrium is produced, tho activityof the emanation and of the products of its further change contributingto the total activity of the preparation. The activity therefore steadilyrises by an amount corresponding with the activity of the ernanationitself, which comprises about 40 per cent. of the total a-radiation, andto the excited activity, which contributes about 35 per cent.of the totala-radiation and the whole of the p- and y-radiations. If, after equilibriumis reached, the radium compound is dissolved in water, the emanationescapes instantaneously into the gas and carries with it 40 per cent. ofthe a-activity. I f the solution is immediately evaporated to dryness, itsactivity a t first consists of two parts, the non-separable activity andthe excited activity due to the active deposit left from the emanation.The excited activity from radium decays fairly rapidly to half theinitial value in about 30 minutes, and completely or almost completelydisappears in the course of a few hours. But concomitantly a newamount is being produced by the separated emanation, and here, asalways, the simple law is followed that the sum total of the activities ofthe products is always constant and equal to that of the radio-elementbefore separation.Hence the activity of the radium after solution andevaporation decays rapidly, and after five hours consists only of thenon-separable activity. The p- and y-rays have completely disappeared,whilst the a-rays are only 25 per cent. of the initial value. The r a d htion from the emanation when first separated consists only of a-rays.But when stored in a closed vessel it gradually changes into the activedeposit, causing the excited activity, and the latter gives both p- andy-rays also. Hence the activity of the radium emanation appears to riserapidly after separation, and after the lapse of five hours the vessel con-taining it shows p- and y-radiation to an extent practically equal to thatof the original radium compound and a-radiation to the extent of 75 percent.of the original. I f now the emanation is blown out of the vesselWied. AWL., 1899, [vi, A], 91266 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in which it has been stored, it carries with it 40 per cent. of the totala-radiation, but the whole of the p- and y-activity and 35 per cent. ofthe a-activity are left behind on the walls of the vessel (excited activity).I n five hours, this will have decayed practically completely, andthe emanation, if stored in the meantime in a fresh vessel, will befound to have reproduced there a further crop of the active deposit.This process, however, does not go on indefinitely with any onequantity of the emanation.Its activity, and correspondingly its powerof producing the active deposit, slowly decays, attaining half the initialvalue four days after separation, and disappearing practically com-pletely after three or four weeks. But if at any time the radium fromwhich it was originally obtained is re-examined, it will be found tohave again generated a fresh quantity of the emanation. As before,the sum of the emanation separated and of that again accumulatingin the radium is a constant. Hence the radium after solution andevaporation slowly recovers its activity, and in three or four weeks theactivity reaches again the maximum, and is equal to what it wasat first.Radium thus affords an excellent illustration of the changesaccompanying radioactivity, and its activity can be separated intothree parts, corresponding with that of the parent element and ofthe first two products of change, by the simple processes of solution,blowing the gas from the solution and storing it in a closed vessel. Italso affords valuable evidence of the independence of the a- and&radiations. The first two changes occur with expulsion of a-raysalone, the p-ray resulting in later changes of the active deposit. I nthe case of thorium also, it is probable that the /3-rags do notresult until the matter passes into the active deposit. For uranium, wehave the simplest possible case. The whole of the a-radiation resultsin the first change of the uranium into uranium X, and the whole ofthe P-radiation in the subsequent change of the latter substance.It has long been known that the laws regulating the decay ofthe excited activities from thorium and radium are irregular, and thecourse of the decay in these cases does not follow a simple geometricallaw. I n the case of thorium, the excited activity obtained by a shortexposure to the emanation rises at first and attains a maximum somehours after the action of the emanation is stopped.It then decays,according to the simple geometrical progression, to half the initialvalue in 11 hours. I n the case of radium, the curves consist of threeparts, a very rapid initial decay, a period of slow change, and finally asimple geometrical decrease to half the initial value in 30 minutes.These curves have been the subject of exhaustive investigations bylXutherford, * and also by Curie and Danne.2 The conclusions arrivedBakerian Lecture, Phil.Tram., 1904, A, 204, 213.Compt. rend., 1903, 136 364 ; 1904,138, 683, 748RADTOACTIVITY. 267at by the former are of the highest interest, for they show thatthe curves can be explained on the view that several successive changesoccur in the active deposit after it is formed from the emanation. I nthe case of thorium, two changes, and in the case of radium noless than five changes, probably occur, the two last in the lattercase being of very long period, and not obvious in ordinary circum-stsnces. I n the case of actinium, the active deposit from the emanationalso probably undergoes two successive changes.Partial separationsof the rapidly succeeding products can in some cases be effected bychemical and physical methods, such as volatilisation at high tempera-ture, electrolysis, deposition of the active matter on bismuth, asin Marckwald’s work, and solution in acids. Perhaps the point ofgreatest interest in this elaborate research is the establishmentin each case of one change in the disintegration series whichproceeds without the expulsion of rays, and which, but forthe fact that it is intermediate between changes in which rays areexpelled, would have been beyond the means of detection. Thisdiscovery opens out a wide field of speculation in its bearing onthe general question of the evolution of matter, for it shows that it isquite possible that changes of the same order of magnitude as thoseoccurring, for example, in uranium may be taking place in ordinaryinactive matter, but unaccompanied by any recognisable radiation andso beyond the present means of detection.M.and Mme. Curie 1 observed that the ordinary excited activity ofradium does not completely decay, but after falling to about 1/20,00Othof its initial value remains sensibly constant at this lower value. Thiswould result if the matter of the active deposit, after passing throughthe rapid changes which give rise to the ordinary excited activity,enters on a stage where the rate of change is very slow, so that whilstthe number of radiant particles expelled in unit time is very smallcompared with the previous changes, the radioactivity continues over amuch longer period before the change is complete.It seems probablethat the active material obtained by Mme. Curie from pitchblende andgiven the name polonium may actually be the slow-changing matterproduced from radium after the rapid changes have run their course.For Mme. Curie found that the activity of polonium decays with time,and in about a year after preparation is only half of the initial value.I n this, as in other cases, the activity of polonium must be regarded as de-caying at the same constant rate whether it is separated from the mineralor not. Hence there must be a continuous production of poloniumfrom the change of one of the radio-elements in pitchblende, and thiswould be a t once accounted for if it were a product of the disintegra-tion of radium.The subject has recently beeii experimentally investi-Mme. Curie, Thesis, 1 ~ . i 5 268 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.gated by Rutherford,l who found that the constant small activityremaining after the complete decay of the ordinary excited activity ofradium was due to two successive changes, the first of which isaccompanied by the expulsion of /3-rays only, and has an estimatedperiod of about 40 years for the change to be half completed. Theproduct of this change gives only a-rays, and has an estimated periodof one year. The latter therefore seems to agree very well in propertieswith polonium, A definite answer to this question cannot be obtainedbefore the rates of change of the two substances have been accuratelycompared. In view of the extraordinarily complex nature of the laterchanges occurring in radium, Rutherford has proposed a new andconvenient system of nomenclature. The first product of the changeof the radium emanation is named radium A, the next radium R, andso on.The following diagram, taken from the paper, illustrates thecomplete course of transformation of the radium atom.RAOlUCl RA0.m. RA0.A RA0.B RAD.C RAD.0 RA0.EACTlGE DfP031T ACTIVF. DEPOSltRAP10 CHAMUOC SLOW CHANGE\V ' -or OFIn the following description, the time in brackets refers to the periodin which the preceding change is half completed. Radium passesinto the emanation with the expulsion of an a-particle (1000 years,see p.274). The emanation then changes into radium A with theexpulsion of a second a-particle (4 days). Radium A changes intoradium B, expelling a third a-particle (3 minutes). Radium B under-goes a rayless change into radium C (31 minutes). Radium C passesinto radium 1) with the expulsion of both U- and P-particles and theemission of y-rays (28 minutes). Radium A, B, and C constitute theactive deposit of rapid change and are the cause of the radium excitedactivity as ordinarily observed. Radium D passes into radium E withthe expulsion of a P-particle only (40 years). Rutherford points outthat sufficient radium D must accuniulate in pitchblende to constitutea new and sensibly permanent radio-element, and makes the suggestionthat the substance obtained by Hoffmann and Strauss2 from pit'ch-Phil.Mag., 1904, [vi], 8, 636. 'L Bcr., 1901, 34, 3035RADIOACTIVITY. 265blende and named by them '' radio-lead '' may have owed its activity tothe presence of radium D. Radium E expels an a-particle (1 year) andpasses into matter which is either completely inactive or changingso slowly that no activity has yet been observed. Radium E corre-sponds well in nature with polonium.An important advance in our knowledge of the a-rays of radium,which bears out in a striking and novel manner the theory of thesuccessive changes occurring in radium, has recently been made byBragg.1 The results obtained are, in addition, of considerable theoreticalinterest.I n this work, an ionisation chamber was employed consistingof two parallel metal surfaces between which the ionisation could bemeasured, the lower surface being made of gauze to allow of the freepassage of the a-rays into the chamber. It was gradually broughtfrom a distance on to a plate on which a solution of a radium salt hadbeen evaporated, and the ionisation measured at various distancesfrom the radium. Mme. Curie showed with a somewhat similararrangement that the ionisation produced by the rays from poloniumextended into the gas a well-defined distance from the polonium andthen ended abruptly, so that just within this distance a largeionisationwas observed, and just without practically none.I n the case of radium,it was found, on bringing the ionisation chamber successively nearerto the radium, that several sudden increases in the amount of ionisa-tion occurred, pointing to the existence of several kinds of a-rays, eachwith a definite penetrative power. By subjecting the radium to pro-cesses, similar to those described, whereby it could be freed from theemanation or from the emanation and the active deposit producedfrom the emanation, Bragg succeeded in eliminating the a-rays fromthese products and in analysing the total radiation into three groups.The most penetrating rays extended to a distance of about 6.2 cm.from the radium in air. These, as he showed, belonged to radium C,adopting the new nomenclature. I f the ionisation near the radium is100, this ionisation equalled about 25.From 6.2 to 4.6 cm., theamount of ionisation remained constant. From 4.6 to 3.8 cm., theionisation increased to nearly treble of that at 6 crn., or 75 per cent. ofthe total, the a-rays from both the radium A and the emanation causingthe increase. These two types are of nearly equal penetrative power,but distinct evidence of two separate sets was obtained. From 3.6 to3.2 cm. no increase occurred, and at the latter distance a furthersudden increase to about four times the initial ionisation at 6 cm. tookplace. The last was due to the 25 per cent. of the total radiationcomprising the non-separable activity. From 3.2 cm., the ionisationremained constant right up to the surface of the radium.Thus, eachBragg, Phd. Nag., 1904, [vi], 719 ; B r a g an4 Kleeman, ibid., 726210 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.a-particle in the disintegration series of radium is expelled at a certaindefinite velocity and is capable of penetrating a certain definite distanceof air before losing its power of ionising. The a-particle from theradium atom is expelled at a lower velocity than the a-particle fromthe emanation atom, and the latter at a lower velocity than that fromradium C, but all the a-particles from each kind of matter are expelleda t the same definite velocity. Thus, the Daltonian conception that theatoms of the same element are all exactly alike applies even to thevelocity with which they expel radiant particles on disintegration.Thisis probably the most severe experimental test to which this conceptionhas ever been subjected, for it niight be imagined hardly possible forany two systems, so extraordinarily complex as the heavy atoms areknown to be, to be so absolutely alike that exactly the same velocityshould be impressed in each case on the fragments during their explosivedisruption.I n the developments of the last two years, abundant evidence hasbeen forthcoming for the view that radioactivity is the result ofchanges in matter of a more fundamental character than those hithertostudied. From the point of view that radioactivity is accompawied bychange, it follows that the final product or products of the changescannot be radioactive, and must therefore be completely beyond therange of detection in ordinary circumstances.On the other hand,since these final products must have been steadily accumulatingthroughout past epochs, they must exist in sufficient quantity to berecognisable in the natural minerals in which the radioactive elementsexist, unless they succeed in escaping in some way from them. Sincethese minerals have been long studied, it may be further stated thatthe final products of radioactive change are probably well knownelements. A review of the composition of the radioactive mineralsfrom this point of view led Rutherford and Soddy 1 to make the sugges-tion that helium was probably the product of radioactive changes.The evidence rested on the inability of helium to enter into combina-tion, or to be condensed in any way by cold or pressure or chemicalattraction.So that its presence in comparatively large volume innatural minerals was in itself remarkable. Further, Sir WilliamRamsay had drawn attention to a fact which, since the discovery ofradioactivity, assumed a new significance, that helium is only found inminerals which contain uranium or thorium, that is, which are radio-active. I n addition, the state in which helium occurs in minerals isexactly analogous to the state in which the emanations, when they donot escape, are retained by solid compounds. I n both cases, the gasesmay be removed by heat or solution, but do not show the least tendencyPhil, Mag., 1903, [vi], 5, 579RADIOACTZVITP. 271to be reabsorbed by the solids from which they are obtained.It seemedlikely that in each case, the gas being formed throughout the mass ofthe solid, it was mechanically imprisoned within the interior, and sounable to escape. The direct proof of this view was obtained byRamsay and Soddy,l who established that there is a continuous pro-duction of helium from radium in sufficient quantity to be directlyrecognised by the spectroscope. A few milligrams of radium bromidethat had been kept some months in the solid state were dissolved inair-free water in vacuo, and the gases liberated were freed from thehydrogen and oxygen which are known to be produced by the decom-position of the water by the radium, by means of a glowing, partiallyoxidised copper spiral. Water was removed by phosphoric oxide andthe radium emanation by cooling with liquid air.The residue asshown by its spectrum proved to be practically pure helium. Theradium emanation that had been condensed out in this experiment wasby suitable arrangements introduced into a second completelyexhausted spectrum tube, which was then sealed. I n this experi-ment, precautions were taken to remove helium if present, by ad-mitting hydrogen, while the emanation was condensed, and againexhausting. Three days after the tube had been sealed, the D, line ofthe helium spectrum made its appearance, and later the whole of thespectrum was observed. This experiment was repeated many timeswith the same quantity of radium, by the simple proces,s of waitingbetween the experiments a sufficient time for the emanation to bereproduced by the radium. The latter was kept in solution untouched,and the gases accumulating removed from time to time by a mercurypump.As the emanation was changing and producing helium withinthe spectrum tube, a fresh quantity of emanation was being regeneratedby the radium, and this process goes on indefinitely, the radium beingtransformed into helium through the emanation.The helium obtained in the first experiment must have been derivedat least in part from the change of the emanation occluded by the solidcompound. There is no experimental evidence as yet available to showwhether helium is not also being produced in the first change of theradium as well as in the later change of the emanation. Rutherfordfavours the view on general grounds that the a-particle is an atom ofhelium, and this involves the consequence that helium is a product inall cases of a-radioactivity, not only in radium, but also in all the otherradio-elements. Strutt has drawn attention to the fact that themineral monazite which contains a fair quantity of heiium containsthorium but no radium.It is by no means probable that helium is the sole product ofProc.Boy. SOC., 1903, 72, 204272 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the changes occurring in radium. I n fact, the evidence of thefinal slow changes show that it cannot be the ultimate product inthe sense of being the last state that the successively disintegratingatom assumes, but is, if not the a-particle, certainly a by-productproduced simultaneously with one or more of the intermediate pro-ducts.The reasons are many why helium is so far the only product thathas been detected.I n the first place, it is the only one that has beenspecifically looked for. The evidence which led to the prediction of itsorigin could only apply to a rare inert form of matter. Secondly,helium can probably be detected in as minute amount as any of thenon-radioactive elements. Thirdly, being uncondensable, it can readilybe separated from large amounts of all other gases. Lastly, its greatrarity and absence from the common materials and reagents of thelaboratory make the evidence of its presence unequivocal. To establishbeyond question the production of any of the commoner elements fromradium with the quantity of the latter at present available, would be adifficult experimental task.The production of helium within a sealed quartz tube contain-ing radium which had been fused and the tube completely ex-hausted before sealing has been shown by Curie, Dewar, andDeslandres. In a photograph of the spectrum taken twenty daysafterwards, by passing a discharge through the tube by means ofexternal electrodes, the helium spectrum was plainly visible.sealed 25 milligrams of radium bromide in asmall U-tube provided with electrodes, filled it ten times with hydrogenand exhausted, and finally sealed it when completely exhausted.Theyobserved the appearance of the helium spectrum after three montlis.A similar quantity of radium was converted into sulphate and heatedfor a long time to a very high temperature in a quartz tube.Duringthe process the tube was filled with hydrogen many times and againexhausted completely before it was sealed. The growth of the heliumspectrum was again observed after a period of three weeks. Theyconclude that unless it is supposed that in spite of the long andrepeated ignition and exhaustion, helium still remained occluded, theonly explanation is that new helium is in fact arising from the radiumpreparation.Simultaneously with these discoveries, advances no less importanthave been made in our knowledge of the energy changes occurring inradioactive substances, again by the use of ordinary methods of in-vestigation.Giesel 2 found that a solution of a radium -salt in water.continuously disengages hydrogen and oxygen in considerable quantity,the hydrogen being in slight excess of the combining proportion. FromHimstedt and Meyer1 Ann. Physik., 1904, [iv], 15, 184. Ber., 1903, 36, 347RADIOACTIVITY. 273measurements by Ramsay and Soddy,l 10 C.C. of the mixed gases areevolved per gram of radium per day over a period of many monthswithout diminution. This represents an energy expenditure of 20calories daily. I n spite of every precaution taken to avoid thepresence of oxidisable matter, the hydrogen was always present inslight excess of the combining proportion. This remarkable fact hasreceived no adequate explanation.Curie and Laborde 2 measured the energy of the radioactive changein radium directly by the heat evolved in a given time from a knownquantity of radium within a Bunsen’s ice calorimeter.Their result that1 gram of radium evolves 100 calories every hour has been repeatedly con-firmed. Next, Rutherford and Barnes 3 analysed the heat developmentand determined the fraction developed at each successive change inthe disintegration series. On the disintegration theory, the intensityof the a-radiation is a measure of the number of atoms disintegrating,and each disintegvtion accompanied by the expulsion of ana-particle was found to evolve a similar amount of heat. Onremoving the emanation by heating from a quantity of radiumwhich had attained its maximum activity, the evolution of heatimmediately decreases, and in the course of a few hours, after thea-activity had fallen to 25 per cent.of the initial, the heat effect haddiminished correspondingly, and was only about a quarter as great asat first, The emanation removed was condensed in a small glass tubeby liquid air. It was found to give out heat exactly to the extent thatthe heat evolution from the radium had diminished, and after a fewhours gave three times as much heat as then given by the radium, orthree-quarters of the total. As the emanation was reproduced by theradium, the heat evolution of the latter increased, whereas as theactivity of the emanation decayed its heat evolution decreased cor-respondingly. The sum total of the two heat evolutions was at alltimes a constant, and equal to that originally given by the radiumbefore the removal of the emanation.Hence the emanation from1 gram of radium present in the condition of radioactive equilibrium,together with the products of the further change of the emanation, evolve75 calories per hour. The integral of the continuously diminishingquantities of heat evolved from the emanation before its activity isexhausted is given by Q/A, where Q is the heat evolved per secondinitially and X is the radioactive constant, or proportion of the emwna-tion changing per second.Ramsay and Soddy 4 measured the actual volume occupied by theequilibrium quantity of emanation from a known weight of radiumunder normal temperature and pressure. This was effected in a veryProc.Roy. SOC., 1904, 73, 346.Q/X = 10,540 calories.Comnpt. r e i d , 1903, 136, 673.Proc. Eoy. SOC., 1904, 13, 346. a Phil. Mag., 1904, [vi], 1, 202.VOL. I. 274 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.narrow thermometer tube, into which the emanation, after it had beenfreed from other gases by condensation, was compressed by means ofmercury, They concluded that the equilibrium quantity of emanationfrom 1 gram of radium occupies a volume not greater than 1.3 cubicmillimetres at normal temperature and pressure.From the three preceding results, the conclusion follows that 1.3 cubicmillimetres of emanation evolve 15 calories per hour, and that 10,540calories are evolved during the course of its complete change. This isa quantity of energy four million times greater than is evolved by thesame volume of hydrogen and oxygen when they explode to formwater.This is a completely expevimental result, and is independent ofany theoretical interpretation which may be put upon it. It is probablythe most far-reaching and revolutionising fact that has yet transpiredin the study of the radioactive substances. This enormous evolutionof energy which accompanies the production of helium from the radiumemanation establishes beyond question the new and fundamentalcharacter of radioactive change. It may be noted and pointed outthat this fact alone negatives the suggestion that the energy of radio-active substances is derived from the outside. It has been suggested, forexample, that all space is traversed by undiscovered radiations to whichordinary matter is completely transparent, but to which the radioactivesubstances are opaque. On this view, the energy traversing a cubiccentimetre of space must be at least 60,000 calories per hour.Thetotal quantity in the universe must therefore be so great that thehypothesis involves far greater difficulties than the facts it is designedto explain. The decay of the activity of the emanation and its con-comitant reproduction by the radium are even stronger argumentsagainst the view.From the volume of the emanation produced pet second froma known weight of radium, Ramsay and Soddy 1 calculated the propor-tion of the radium changing per second, that is, the radioactiveconstant of radium. They deduced that about 1/1150th part ofthe radium changes every year. A similar result has been theoreti-cally deduced by Rutherford from the energy evolved from radium,and the energy of the a-particle as calculated from its mass andvelocity.The comparatively rapid rate at which radium undergoesdisiutegration shows clearly that the element must be being repro-duced by some means in the minerals containing it. I n 1903,Rutherford and Soddy 2 put forward the view that it was probably aproduct of the disintegration of uranium. This question has not yetbeen definitely settled.Ramsay and Collie,3 using methods similar to those employed in theYroc, Izoy. Soc., 1904, 73, 346.3 Proc. Roy. Soc., 1904, 73, 470.Phil. Mag., 1903, [vi], 5, 590RADIOACTIVITY. 275experiments on the production of helium from the emanation, havesucceeded in showing that the emanation before it changes intohelium possesses a definite and characteristic spectrum, which wasmapped, Sir William and Lady Huggins1 have photographedthe spectrum of the fluorescent light of radium in air, and shownthat it consists of the negative glow spectrum of nitrogen. Accordingto Crookes and Dewar, unless nitrogen is present in the atmosphereonly a continuous spectrum is obtained.This was found to be thecase in an atmosphere of helium, and also in a vacuum.The rate of change of the elements uranium and thorium maybe calculated from the rate of change of radium by comparing thea-radioactivity and the number of changes in which a-particles areevolved in each case.The best determinations of the activity of thepurest preparations of radium show that this element possesses abouttwo niillion times the a-activity of uranium or thorium, which inthis respect are very nearly equal. I n thorium, the same numberof changes cause the a-activity as in radium in the circumstances inwhich the activity is usually measured. The rate of change of thoriumis therefore about 5 x 10-1O per year. I n uranium, only one change isknown, and the rate of change is therefore about 2 x 10-9 per year.I n the following table, the unstable elements at present recognisedhave been arranged in the order of their instability. I n the first column,the radioactive constants, as defined by the proportion changing persecond, and in the second column the average lives are given :Actinium enianatioii ...........Thorium emanation ............Actinium B ...................Radium A ........................Radium C .......................Actiniuni A .....................Thorium B .. ..................Thorium il ......................Radium .emanation ............Thorium X .......................Uranium X .......................Radiuiii E .....................Radium D .....................Aotiiiiuni .......................Radium ...........................Uranium ...........................Thorium ...........................Avesage life.5-8 seconds87 2 ,130 9 ,264 ,,31 minutes40 7 ,60 I 979 I ,16 hours5 days, 19 hours* 7 J ?:32 ),about 18 inonths,, 60 years1,150 years5 x los ,,-.L X 109 ,,It will be seen that a wide range of stability is represented betweenlimits of a few seconds on the one hand and cosmical epochs on theother. The question whether there may net be an opposite process innature, as yet undiscovered, whereby the parent elements themselvesPTOC. Ecy. Sot:., 1903, 72, 196 and 409276 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.are being reconstructed, and their quantity maintained, was discussedby the author in a recent paper.' One of the most interesting resultsof the study of radioactive change is that it reveals the possibility of aslow continuous evolution of the elements, such as has frequently beensuggested, without in any way subverting or altering the foundationson which the present evidence of the conservation of the elementsrests.The idea of a gradual conversion of one elementary form ofmatter into another is opposed to chemical evidence, for fractionalmethods should have revealed the existence of such a process. Radio-activity has brought to light a type of change which, whilst of anydegree of slowness, so far as the mass of matter is concerned, is suddenfor the individual particle. Since the rates of change appear tobe constant and invariable in all circumstances, it follows that notype of matter intermediate between the parent element and final pro-duct can accumulate in sufficient quantity to come within rangeof direct detection if it is changing faster than a very slow rate. Therapidity of change as measured by the degree of radioactivity must beinversely proportional to the quantity capable of existence at one time.The experimental results, so far as they are available, show thatthe quantities of uranium, radium, and polonium in pitchblende are asl O Q : 103 : 1, and these ratios are of the same order as the relativeactivity or rates of change, We have here the introduction intochemistry of a conception analogous to that of evolution in thebiological sciences.The existing state of matter and the presentcomposition of the earth must be regarded as the direct consequence ofpast occurrences. The periodic table becomes indicative of the formsof atomic structure that are stable, rather than of those that arepossible. The question why the majority of the atomic weightsapproximate to multiples of hydrogen still remains without explana-tion, but it has been put on an entirely new basis; for of the eighteenforms of matter given in the preceding table only the last threeare assigned places in the periodic table, and it seems probablethat forms of matter intermediate between the members of that tableare not known only because they cannot survive.From t,his point ofview, there are no longer any grounds for believing, as in Prout'shypothesis, that the approximation of the atomic weights to wholenumbers argues in favour of a step by step condensation of matter, byunits equal to the hydrogen atom. The periodic law represents aperiodic variation in stability with mass in which the positions ofmaximum stability correspond to multiples of the mass of the hydrogenatom in the greater number of cases, but t'he reason for the periodicityof stability remains to be elucidated.An important argument may be drawn from the fact that inMen&.Manchester PhiE. SOC., 1904, 48, ii, Wilde LectureRADIOACTIVITY. 277the stars few if any forms of matter not existing on the earth arefound, for this must point to the conclusion that the law developedfrom the study of radioactive change, that atomic stability is indepen-dent of external conditions, holds universally over much wider rangesof temperature and under conditions other than those for which it hasbeen experimentally verified.Sir Norman Lockyer’s theory is of morethan usual interest in the present connection, as it was based primarilyon accurate astronomical data. It seems that the main fact on whichthis theory was based is in strong agreement with recent developments.Lockyer found that the temperature of a star appears to be in inverseratio to the complexity of its composition, so that if the stars areclassified in order of descending temperature the hottest give spectracorresponding to the lightest elements only, the heavier elementsgradually making their appearance in increasing numbers withdecreasing temperature. This is in agreement with the fact thata heavy element is resolved with the evolution of an enormous amountof energy. But it is now clear that if the process which Lockyerimagined occurred, and the light elements condensed into the heavyones, so great an absorption of energy must follow that the heat of thestar on cooling would represent only an insignificant fraction ofthat required.So that it seems more justifiable to assume that in thestars, as in the earth, evolution is proceeding from the heavy towardsthe lighter forms.I n conclusion, it may not perhaps be out of place to call attention tosome considerations attracting great attention among physicists, whichalthough hardly yet within the scope of chemistry, may exert a pro-found influence in the future. The discovery of the corpuscular typesof radiation, firstly the cathode rays and now the a- and @-rays, hasgiven great support to the modern view of the nature of electricity.This view has been happily called the atomic theory of electricity, todistinguish it from the older fluid theories.Faraday’s law of electro-lysis suggested the conception of the unit or atomic charge ofelectricity possessing the same qualities of invariability and indivisi-bility as the material atom. The development of the electromagnetictheory of light, and its establishment after the researches of Hertz,effected the further removal of the dividing line between electricityand matter by showing that the electric charge possesses a certaininertia, or mass. The magnetic field created in the ether by themotion of an electric charge and which for ordinary speeds is pro-portional in intensity to the velocity of the charge, represents a certainstore of energy in the medium.So that an electric charge resistsalteration of velocity or possesses inertia, indistinguishable from thatpossessed by matter. For similar charges, the value of the electricInorgni~ic Evolution, 1900278 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.inertia increases with the concentration of the charge. On the olderfluid view of electricity, in which even in the case of single atoms thecharge was supposed to be uniformly distributed over the surfaceaccording to the ordinary laws of electrostatics, the conception ofelectrical inertia remained of no more than abstract interest. For evenin the case of the hydrogen ion, the most intensely charged form ofmatter known, the charge is too diffused for its inertia to be compar-able with that of the uncharged atom.With Professor J. J.Thornson’s elucidation of the nature of the cathode rays, and hisdetermination of the mass of the cathode-ray corpuscle, the property ofelectrical inertia at once assumed extraordinary practical interest.The extremely small size of the corpuscle as evidenced both by thevalue found for its mass and its power of penehating ordinary solidmatter, made it appear probable that it was the atom of electricity, orelectron, dissociated from matter. For this to be the case Thonison hascalculated that the charge must be concentrated within a sphere of dia-meter one hundred-thousandth of that usually assigned to the diameterof the molecule.1 The observed mass, namely, about one-thousandth ofthe hydrogen atom, would then be of purely electro-magnetic originand an attribute of the charge.I n this sense, the electron has beenrecognised by Larmor and others as a possible basis of matter, thevarious atoms being systems composed of the requisite number ofdiscrete electrons in stable groupings to give a total mass equal to theatomic mass. I n this way, all material and mechanical phenomena wouldpossess ultimately an electromagnetic origin. Such a view differs in onefundamental point from the older ideas, and it has fortunately been foundpossible to obtain in the case of radium something of the nature of acrucial test by actual experiment between the rival views. Althoughfor ordinary speeds, such as those dealt with in mechanics, chemistry,or physics, the electrical inertia of an electron remains constant, it wasdeduced in 1881 from the electromagnetic theory of light by Heaviside,that the inertia of the electron must increase when the velocity of lightis approached, and at that velocity become infinite.I n the case of theP-rays of radium, Kaufmann 2 has shown that the most penetrating raysconsist of electrons travelling with a speed of 95 per cent. of that oflight. At this speed, the mass of the electron, if it is entirely of electro-magnetic origin, should be considerably greater than the normal valuefound in the case of the cathocle-rays or the slower moving P-rays ofradium. Kaufmann showed that the ratio of the charge to the mass ofthe electron continuously decreases as the velocity increases, and for thefastest moving electrons is only two-fifths of the ordinary value. J . J.J. J. Thomson, Electricity and illatter, 1904.Compt. Tend., 1902, 135, 577RADIOACTIVITY. 279Thomson 1 has shown that these results are in good accordance withthe theoretical values deduced from the assumption that the mass isentirely electromagnetic. As this is the only case in which any varia-tion has been observed in the ratio of the charge to the mass of theelectron, although a considerable number of cases have been examined,and as the result was definitely predicted from the electromagnetictheory, it furnishes a very strong argument in favour of the new views.I f they are accepted they lead directly to the result that the law ofthe conservation of mass can only have a limited application. I nmechanical and chemical phenomena, matter travelling with velocitiesof the order of that of light is unknown, and the law therefore appliesrigidly. But in radioactive change it should not apply. If, asappears certain, the energy of radioactive change is derived from theinternal energy of the atomic structure, the constituent electrons orpotential a-particles which go to make up the atom must be per-manently in extremely rapid orbital or oscillatory motion, approachingin some cases to that of the velocity of light. For it is recognised thatthe velocity with which the radiant particles are expelled are too greatto have been suddenly produced by the action of any known force,The constituent electrons of a radium atom must therefore vary in massaccording to their velocity. On the new views, no simple numericalrelations should exist between the atomic weights, for the latter are toa certain extent a most complex function of the internal energy ofthe atom. On disintegration, the expelled electrons, on encounteringobstacles, are absorbed and stopped, so that in the case of the fastermoving electrons a diminution of mass must simultaneously occur,Hence the products of the disintegration of radium must possess atotal mass less than that originally possessed by the radium, and a partof the energy evolved must be considered as being derived from thechange of a part of the mass into energy. I n future, it may be possibleto put this revolutionary deduction to the test of direct experi-ment. As, however, the loss of weight in radium under conditionsin which the expelled electrons escape freely from the system is sosmall that it has not yet been detected, it is likely that a considerabletime must eIapse before enough radium is available for the experiment.But there is no doubt that it is only a question of time before itbecomes possible for even these fundamental conclusions, arising outof what but a short time ago was one of the most abstract regionsof physics, to be put to the actual test of crucial experiments in thelaboratory.The year 1904 witnessed the appearance and the successful comple-tion of the first year of existence of a new quarterly journal, DerCo?adzcction of Electricity through Gases, 1903, 535280 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Jahrbuch der Radioahtiwitat zcnd Electronik, under the able directionof Prof. J. Stark, of Gottingen. The journal has already justified itsexistence, if only by the publication of a complete and carefullyclassified catalogue of all the literature dealing with these subjects,from their beginning right up to the end of the year that has justdosed. It is a pleasure, in acknowledging the assistance derived frombhis catalogue in the preparation of this report, to wish the newjournal a long continued career of usefulness.FREDERICK SODDY.R. CLAY AND SONS, LTD., BREAD ST. HlLL, E.C., AND BUNQ-iY, SUNYOLK

ISSN:0365-6217    

DOI:10.1039/AR9040100244

出版商:RSC    

年代:1904

数据来源: RSC