摘要:

ANNUAL REPORTSON THEPROGRESS OF CHEMISTRYANNUAL REPORTSA. C. CHAPMAN, F.I. C.C. H. DESCH, D.Sc., P1i.D.H. J. H. FENTON, M.A., Sc.D., F.R.S.A. FINDLAY, M.A., D.Sc., Ph. D.A. D. HALL, M.A.ON THEW. D. HALLIBURTOS, M.D., F.R.S.J. T. HEwITr, M.A., D.Sc., Ph.D.A. HUTCHINSON, M.A., Ph.D.H. 0. JONES, M.A., D.Sc.H. MARSHALL, D.Sc., F.R.S.PROGRESS OF CHEMISTRYF O R 1 9 0 7 .ISSUED BY THE CHEMICAL SOCIETY.H. E. ARMSTRONQ, Ph.D., LL.D.,E. C. C. HALY.HORACE T. BROWN, LL.D., F.R. S.A. W. CROSSLEP, D.Sc. , Ph.D. , F.R.S.F. R,. S.WYNDHAM R. DUNSTSN, M.A., LL.D.,F.R.S.M. 0. FORSTER, D.Sc., Ph.D., F.R.S.R. MELDOLA, F.R.S.G. T. MORGAN, D.8c.Sir W. RAMSAY, K. C. B., LL.D., F.R.S.A. SCOTT, M.A., D.Sc., F.R.S.W. A. TILDEN, D.Sc., F.R.S.JOHN WADE, D.Sc.4lFbitaz: :J.C. CAIN, D.Sc., Ph.D.% 11 b - &;bit or :A. J. GREEWAWAP.8r;air;taut %itXr-@bb-itar :C. H. DESCH, D.Sc., Ph.D.V O l . IV.LONDON:GURNEY & JACKSON, 10, PATERNOSTER ROW, E.C.1908RICHARD CLAY AND SONS, LIMITED,BREAD STREET HILL, E.C., ANDBUNQAY, SUFFOLKPREFACE.IN order to render the Annual Reports as comprehensive aspossible, slight variations will be made in the list of sections fromtime to time, For example, the Reports for 1908, while embracingas heretofore sections on A gricultural, Analytical, Inorganic, Organic,Physiological, General and Physical Chemistry, will include a Reporbon Crystallography in the place of Mineralogy, and advances inStereochemistry will be embodied in the sections directly concernedinstead of being placed in a separate division.The Report on Radio-activity, postponed until 1909, will cover the interval since thepresent issue.J. C. CCONTENTS.PAGEGENERAL AND PHYSICAL CHEMISTRY.INORGANIC CHEMISTRY. By HUGH MARSHALL, D.Sc., F.R.S. . . 34ORGANIC CHEMISTRY-ALIPHATIC DIVISION. By H. J. H. FENTON,M.A., Sc.D., F.R.S. . . - . . . . . . . 74ORGANIC CHEMISTRY-HOMOCYCLIC DIVISION. By CECIL H.DESCH, D.Sc., Ph.D. . . . . . . . . . . 109HEWITT, M.A., D.Sc., Ph.D. . . . . . . . . 138STEREOCHEMISTRY. By H. 0. JONES, M.A., D.Sc. . . . . 177ANALYTICAL CHEMISTRY. By ALFRED CHASTON CHAPMAN, F.I.C. . 199PHYSIOLOGICAL CHEMISTRY. By W. D. HALLIBURTON, M.D., F.R.S. 226AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY.By A.D. HALL, M.A. . . . . . . . . . 261MINERALOGICAL CHEMISTRY. By ARTHUR HUTCHIKSON, M. A., Ph.D. 279RADIOACTIVITY. By FREDERICK SODDY, M.A. . . . . . 311By ALEXANDER FINDLAY,M.A., D.Sc., Ph.D. . . . . . . . . . 1ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. By J. TTABLE OF ABBREVIATIONS EMPLOYED I N THEABBREVIATED TtTLE.Abstr. . . . . .Anaer. J. Sci. . . .AsLalyst . . . .Annalen . . . .Ann. Physik . . .Ann. China. anal. . .Ann. of Botany. . .Ann. 12ejiot-t. . . .An2eiye.r K. Akncl. Wias.1Vien. . . . .Apoth. Zeit. . . .Ber. , . . .Brit. ked. J. . . .Bz~ll. Coll. Ayr. T8kyd .Bull. Soc. chirn. . .BILL?. SOC. chinz. Belg. .BUZZ. Soc. frang. Xin. .Centr. Bnkt. Par. . .Centr. Min. . . .Chem. NGWS . ..Chem. Eev. ~ett-Hccrn-~nd.Chein. Trade J. . .Chmn. Zeit. . . .Chem. Zentr. . . .Compt. rend. . . .Gazzetta . . .Jahrb. Min. Bei2.-Bd. ,Jahrb. Rndioaktiv. Elek-J. Agric. Scsyci. . . ,J. Amer. Chem. Xoc. , .J. Chim. phys. . . .J. Landw. . . . .J.pr. Chem. . . .J. Xoc. Chem. Ind. , .J. SOC. Dyers. , . .Monatsh. . . . .tronik.REFERENCES.JOURNAL.Absttacts i n Journal of the Chemical Society.diiiericaii Jonrnal of Science.The Analyst.Ju.jtns Liebig’s .\nnulen 11er Chemie.dnnaleri der Physik.Aunalcs de Chirnie analytique aypliquge h l’Iuclustrie,Aniinls ot‘ Botany.Annrial Reports of the Chemical Society.Arizeiger der Iiaiserliche Akademie der WisseiiApotlieker Zeitung.Kerichte der Deutschen chemischen Gesellschaft.British Medical Journal.Knlletin of the College of Agriculture, Imperial Uni-versity, Tokyo.Bnllotin ile la SociBtk chimique de France.Billletin de la SociktB chimiclue de Relgiqne.Bulletin de la Sociktd frangaise de Minkralogie.Centralblatt fiir Bakteriologie, Parasitenknnde undCentralblatt fiir Minernlogie, Geologie und Palaeonto-Chemical News.Chemische Revue iiber die Fett- und Harz-Indnstrie.Chemical Trade Journal.Chemiker Zeitung.Chemisches Zentralblatt.Comptes rendus hebdomadaires des S6ances deGazzetta chimica italiana.News Jahrbuch fur Mineralogie, Geologie und Pal-Jahrbuch der Radioaktivitiit und Elektronik.h 1’Agriculture, h la Pharinacie et h la Biologie.schaften i n Wien.Infektionskrankheiten.logie.1’Acaddmie des Sciences.aeontologie. Beilage-Band.Jouriial of Agricultural Science.Journal of the American Chemical Society.Journal de Chimie physique.Journal fiir Landwirtschaft.Journal fur praktische Chernie.Journal of the Society of Chemical Industry.Journal of the Society of Dyers and Colourists.Monatshefte fiir Chemie und verwaiid te Theile andererWissenschaften.NZCOVO Cim.. * . I1 Naovo Cimentox TABLE OF ABBREVlATIONS EMPLOYED IN THE REFERENCES.ABBREVIATED TITLE.Phil. Mag. . .Ph ysikal. Ze itseh. .Proc. . , . .Proc. Cantb. Phil. Xoc.Proc. Roy. Soc. . .Trans. . . .Trans. Faraday Soc. .TSCJL. Min. Mitt. .Wien. Sitzungsbev. .Zeitsch. anal. Chenz. .Zeitsch. angew. Chem.Zeitsch. Elektrochem. .Zeitsch. Kryst. Nin. .Zeitsch. Nahr. Genussm.Zeitsch. Zzcckerind. Bahm.JOURNAL.Philosophical’Magazine (The London, Edinburgh andPhysikalische Zei t schrif t.Proceedings of the Chemical Society.Proceedings of the Cambridge Philosophical Society,Proceedings of the Royal Society.Transactions of the Chemical Society.Transactions of the Faraday Society.Tschermak’s Mineralogische Mitteilungen.Sitzungsberichte der Kaiserliche Akademie der Wissen-Zeitschrift fur analytische Chemie.Zeitschrift fiir angewaiidte Chemie.Zeitschrift fiir Elektrochemie.Zeitschrift fiir Krystallographie und Mineralogie.Zeitschrift fur Untersuchung der Nahrungs- undZeitschrift fijr Zuckerindustrie in Bohmen.Dublin).schafteii in Wien.Genussmittel

ISSN:0365-6217    

DOI:10.1039/AR90704FP001

出版商:RSC    

年代:1907

数据来源: RSC

摘要:

INORGANIC CHEMISTRY.ALTHOUGH there has been a considerable output of interesting andimportant work, there is again nothing of a very novel or startlingcharacter to record with regard to the progress of Inorganic Chem-istry during the period covered by the present Annual Report. Nonew element, or pure compound of a new element, has been isolated,although indications have been obtained of the existence of ahitherto unknown constituent in the rare-earth series. The trans-mutation of the elements, if placed beyond all doubt, would, ofcourse, be of much greater interest and importance than the merediscovery of new elements to fill up recognised blanks in theperiodic system; but, whatever be the ultimate result of Sir Wm.Ramsay’s work in this connexion, the matter has not yet reacheda stage which calls for its being treated in a part of the Reportdealing purely with inorganic chemistry as usually understood.The year’s work has followed pretty closely along previouslyestablished lines ; considerable use has been made of the facilitiesprovided by modern chemical equipment and methods.The easyattainment of high temperatures by means of electric furnaces, &c.,has led to a greatly extended study of compounds such as carbides,silicides, borides, &c., of alloys of the metals, and of mixtures moreor less analogous t o these.One can hardly mention the matter of high-temperature researchwithout referring to the great loss which befell this branch of inor-ganic chemistry by the death of Henri Moissan early in the year, forhe was a pioneer in such work.In the other direction, there has also been a fair amount of low-temperature work, although to nothing like the same extent.Itis evident, however, that liquid-air machines, as well as electricfurnaces, are becoming more and more part of the ordinary equip-ment of a chemical laboratory, with great advantage, even to theworker who does not wish to reach the extreme limits of practicabletemperatures, but who, nevertheless, occasionally finds it highlydesirable t o work a t temperatures well outside those ordinarilyobtainable. The great improvements which have recently beeneffected in the preparation of pure silica-ware, and the cheapeninINORGANIC CHEMISTRY. 35of the cost, have also placed a new power within the reach ofchemists generally.The study of the “rare earths” is another fairly well-definedbranch of work which has been steadily developed during the year,and in whicb considerable progress has been made; the same is thecase in connexion with the investigation of numerous “ complex ”salts, such as the ammonia derivatives of the cobalt and platinummetals, various chromium derivatives, &c.Werner, whose name isso intimately associated with the recent .advancement of our know-ledge concerning complex salts, has been extending his theoreticalconclusions, derived from his studies of these compounds, more andmore into the region of the simpler salts, and his recent papersdealing with these matters are very interesting and suggestive.Revision of Atomic TVeights.The recently obtained values for the atomic weight of nitrogenare discussed by D.Berthelot? who considers that they amplyconfirm the values 14.007 and 14.000 obtained by him ten yearsago.The revision of the combining weights of various elements, whichhas in recent years been so admirably carried out by T. W. Richardsand his co-workers, is being continued. The atomic weight of silverhas been determined, in conjunction with G. S. Forbes,2 by the syn-thesis of silver nitrate; in four out of six experiments, the ratioAg: AgNO, was found to be 100:157.480, and in the remainingtwo, 100: 157.481. The value for silver to be deduced from theseresults, of course, depends on what value is accepted for nitrogen;if this is taken as 14.037 (for an upper limit), then Ag=107.930,whilst if it be taken as 14.008 (for a lower limit), then Ag=107-880.Richards and G.Jones have obtained revised values for sulphurand chlorine by the conversion of silver sulphate into chloride.Ten experiments gave, as an average result for the ratioAg2S04: AgC1, the value 100: 91.933, the extremes being 91-929and 91.936. Here, again, the values for the atomic weights, t obe deduced from this result, depend on the value adopted fornitrogen, since the value for silver is involved. Correspondingwith the limits stated in the preceding paragraph, the limitsfor chlorine are 35.473 and 35.457 respectively, and those for sulphurare 32.113 and 32.069. The last value is the one which most closelyagrees with that deduced from the more recent work on gas densities.The revision of the atomic weight of potassium has been carrieda stage further; as mentioned in last year’s Reporb, Richards andAbstr., 1907, ii, 680.Ibid., 685. 16iCE., 685.u 36 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Stahler, working on pure potassium chloride, obtained the valueK=39.114, adopting the value Ag=107.93. Richards and E.Mueller 4 have now published the results of similar work performedon pure potassium bromide. Four determinations gave the meanvalue of 100:63'373 for the ratio AgBr:KBr, and ten determina-tions gave the mean value 100 : 110.319 for the ratio Ag: KBr.These give respectively the values 39.1135 and 39.1143 for theatomic weight of potassium (Ag = 107.93 as before).From all the various series of determinations, Richards concludesthat K=39.114 may be taken as the probable value, assumingAg = 107-93, Br = 79.953, C1= 35,473 ; 0 = 16 serves as the basisthroughout.The close agreement obtained in the two investigationsindicates a high degree of accuracy for the values for chlorine,bromine, and silver, relatively to one another.P. A. Guye and Ter-Gazarian 5 have checked the value for theatomic weight of chlorine by accurate determinations of the densityof hydrogen chloride. For this purpose, the gas was prepared fromsodium chloride and swlphuric acid, dried by sulphuric acid andphosphoric oxide, liquefied, and fractionally distilled. The weightof one litre was found to be 1.6398 under standard conditions(Leduc's value is 1.6409) ; this gives C1= 35.461.The questions whether or not tellurium is a homogeneous element,and, if so, what is the correct value t o adopt for its atomic weight,have been the subject of an important investigation by H.B. Bakerand A. H. Bennett.6 Eight different methods of fractionation wereemployed, and in no single case could any difference be detectedbetween the first and the last fractions, other than what fell withinthe limits of experimental error. The following were the methodsapplied fractionally : (1) Crystallisation of telluric acid ; (2) Dis-solution of barium tellurate; (3) Distillation of tellurium; (4) Dis-tillation of tellurium tetrachloride ; (5) Distillation of telluriumdioxide ; (6) Decomposition of tellurium hydride ; (7) Electrolysis oftellurium tetrachloride and tetrabromide; (8) Precipitation fromsolution of tellurium tetrachloride by addition of water.For the purpose of testing most of the fractions, they were con-verted into dioxide, and the percentage of oxygen in thesamples of dioxide was determined by reduction with sulphurin an ingenious manner devised by Berzelius, and employed byhim in determining the equivalent value of arsenic; the methodconsists in heating the dioxide with sulphur in an apparatus soarranged that nothing but sulphur dioxide can escape.The othermethod adopted was to convert the fractions into tellurium, and thendetermine the proportion of tetrabromide obtained from this.4Abstr., 1907, ii, 615.51bid., 80. Trans., 1907, 91, 184INORGANIC CHEMISTRY. 37The average percentage of oxygen in the dioxide was thus foundto be 20.048 (0=16, S=32.06), and of tellurium in the tetra-bromide, 28.518. The value for the atomic weight deduced fromthese results is consequently : by the first method, Te = 127.609 ;by the second, Te=127*601 (Br=79*96). The probable value iStaken as 127.60.Since the tellurium employed was in some cases of widely differentorigin, the results of the investigation may be taken as conclusive ofthe homogeneity of the element, and confirm the relative positionsof iodine and tellurium as regards order of atomic weight.Several years ago, an investigation by Thiel led t o a considerableincrease in the accepted value for the atomic weight of indium.This is confirmed by F.C. Mathers,’ who analysed the trichlorideand the tribrornide, prepared by passing dry chlorine gas or drybromine vapour over the metal, and subliming the product ineach case. These methods not only gave consistent resultsthroughout each series of five experiments, but the two valuesfound by them agree well with each other; they were 114.88and 114.86. The value In=114*9 may therefore be accepted(Ag= 107.92 ; Br = 79.955 ; C1= 35.47).Several determinations of atomic weights will be referred t o inci-dentally in connexion with the rare-earth group.G. D. Hinrichs8 discusses the “absolute ” atomic weight of anumber of elements which have recently been investigated byvarious workers; he urges the adoption of the following roundnumbers as being the true atomic weights of the elements indi-cated: C=12; C1=35*5; Mn=55; Br=SO; Ag=108; Dy=162.5.Rare Earths.As already indicated, there have appeared during the year aconsiderable number of papers, some of them long memoirs, dealingwith the substances generally included under this heading.Manyof these are the result of a vast amount of careful and laboriouswork, involving the preparation of scores, or even hundreds, offractions, and repeated examination of the products thus obtained.One of the chief aims of workers in this field is, of course, toobtain better modes of fractionation, by discovering which saltsshow the greatest differences of solubility in various solvents, andvarious new processes have been suggested.A very extensivememoir on the preparation of pure neodymium oxide, and on newmethods of separating the rare earths, has been published by 0.I-I~lmberg.~ I n this paper, a large number of organic salts of theAbstr., 1907, ii, 352. Ibid., 90, 450, 622, 679. 9 Ibid., 9038 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.rare-earth metals are described, principally those derived frombenzenesulphonic acid and its nitro-, chloro-, and bromo-substitu-tion products. It was found that the solubilities of the m-nitro-benzenesulphonates in many cases are widely different from oneanother, more so than with other salts, and that therefore improvedfractionation could be effected by their means. By repeatedlyworking up the impure neodymium salt, it was found possible t opurify it so completely that a serieb of the various later fractionsyielded material exhibiting a constant result for the atomic weight(the oxide-sulphate method being used).The average result ofseveral concordant sets of atomic weight determinations gave thevalue Nd=144.08. The method was also found t o work well forthe purification of samarium oxide, yielding a constant material,for which the atomic weight value Sa=150 was obtained. It didnot yield good results for the preparation of pure gadoliniumoxide, however, but in this case a satisfactory method of separationfrom terbium was found in dissolution of the material in picricacid and fractional precipitation with ammonia.From this mate-rial, the atomic-weight value Gd = 156 was obtained.C. A. v. WelsbachlO has devoted attention chiefly to the isola-tion, in a satisfactory degree of purity, of the members of theytterbium group. The method which he adopts is first t o obtainthem together in the form of basic nitrates, and then t o frac-tionate them by conversion into double ammonium oxalates andcrystallisation of these from saturated aqueous solution of am-monium oxalate. The solubilities of the double salts in this solventvary very considerably; for example, the solubility of the ytter-bium compound is ten times greater than that of the holmiumcompound.According to Langlet,ll the best method of separating holmiumfrom erbium and ytterbium, provided the latter is not present inlarge quantity, is by fractional crystmallisation of the chloridesfrom solution in hydrochloric acid of constant boiling point. Asregards the testing of the rare earths for purity, he holds that thegenerally accepted criterion of constancy of value found for atomicweight is not trustworthy by itself, since h e finds that such con-stancy is not always associated with constancy of absorption spec-trum.Urbain 12 states that by the oft-repeated fractional crystal-lisation of ordinarily pure ‘‘ ytterbium ” nitrate from solution innitric acid of density 1.3, he has obtained end fractions whichexhibit lower and higher atomic weight values (169-9-173.8) ;those of low atomic weight show arc-spectrum lines which are t o beattributed to thulium, whilst those giving the higher values showlo Abrtr., 1007, ii: 26.lbid., 955. l? lbid., 9%INORG AKIC CHEMISTRY. 39well-marked lines which must be ascribed to a, new element,‘‘ lutecium.” Rejection of those lines which come into prominencein the end fractions leaves the spectrum of ytterbium proper, ‘‘ neo-ytterbium.” Lines which did not coincide with those of any knownelement were also obtained by von Welsbach (v. sup.) in some of hisfractions.A new method for the separation of yttrium earths is describedby C. James13; the oxalates are dissolved by warming with asaturated solution of ammonium carbonate in dilute ammoniumhydroxide, and fractional precipitation is effected by boiling thesolution.It is claimed that by this method a rapid separation oferbium from holmium, &c., can be effected. Work in this grouphas also been carried out along recognised lines by A. Bettendorff,14and by V. von Lang and Haitinger 15; the latter give crystallo-graphic descriptions of some of the compounds examined.Cerium compounds have received a considerable amount of atten-tion. The question as to the position of this element in the fourthgroup of the periodic system, in view of its apparent tendency t oform tervalent rather than quadrivalent derivatives, is discussedby G. A. Barbieri, who also describes new methods of preparingceric salts.16 He is of the opinion that cerous compounds are morestable than ceric only in cases where cerium constitutes the cation;whenever complex anions containing cerium can be formed, thenthere is a ready change from the cerous t o the ceric condition.Alarge number of cerous salts, especially those of organic acids, havebeen prepared by G. T. Morgan and E. Cahen,l7 and a lengthypaper dealing with cerium compounds generally has been publishedby Wyrouboff and Verneuil.18A matter of considerable practical interest is dealt with by R. J.Meyer and A. AnschUtz,lg who have sought t o obtain from thechemical side some indication as t o the correctness or otherwise ofthe explanations which have been put forward for the high emis-sivity of the incandescent Auer mantle. An interesting point notedby them is that when the dioxides of thorium and cerium areheated together, no loss of weight can be detected, but, if theresulting material is mixed with potassium iodide and hydrochloricacid and then distilled, less iodine is obtained than would havebeen the case with the original cerium dioxide.It was foundthat thoria could thus render inert about 7 per cent. of ceriumdioxide, so presumably the 1 per cent. which is added t o Auermantles is all in the peculiar condition indicated above. The authors13 Abstr., 1907, ii, 467.lfi Ibid., 466, 467.Abstr,, 1907, ii, 26.l4 Ibid., 172.lY Ibid., 557.l5 Ibitl., 204.Tyaiis., 1907, 91, 47540 ANNUdL REPORTS ON THE PROGRESS OF CHEMISTRY.point out, also, that, when cerium nitrate is heated alone, theresidual oxide contains more oxygen than corresponds with CeO,,and may even approach what is requisite for CeO,.For the preparation of cerous salts from cerium dioxide, Marino2Orecommends treatment with the appropriate acid in presence ofquinol, which acts as a reducing agent; the method may even beused as a means of effecting the separation of cerium and thorium,on account of the latter not being easily brought into solution inthe form of its ignited dioxide.For the preparation of the metals of the rare earths, for example,cerium, Muthmann and others 21 recommend the electrolysis of solu-tion of the oxide dissolved in the fluoride of the metal; otherfluorides, such as cryolite, potassium fluoride, or calcium fluoride, donot give satisfactory results.The Argon Group.Moureu and Biquard22 have examined the gases extracted froma large number of mineral springs. For the determination of therare gases present, the chemically inactive residues were submittedto fractionation by Dewar's method of absorption in wood charcoala t low temperatures.The principal ingredient was found to behelium, which varied greatly in amount in the different cases,from a minimum of 0.00063 per cent. of the total gases in the Chiitel-Guyon spring, t o a maximum of 5-34 per cent. in that of Maizikres(the waters of which also contain krypton); the quantities of neonpresent were too small t o be separated. The proportion of heliumoccurring in the natural gas of various wells in America has beendetermined by Cady aiid McFarland 23; in forty-one samples, it wasfound to vary from merely a trace up to 1.84 per cent.According to C ~ a t e s , ~ ~ there are no lines observable in thespectrum of the residue of light gas fractionated from more than70,000 litres of air other than those due t o helium, neon, and hydro-gen; there seems therefore to be no reason to assume the existence inair of any rare gas having a density less than that of helium.Hisresults further indicate that the proportion of hydrogen (which,however, it is difficult to determine) is much less than i t has beenstated to be by some previous observers; it is probably only of theorder of one part by volume in one and a half million parts of air.F o r the preparation of pure helium from the gases extracted fromcleveite, Jaquerod and Perrot 25 take advantage of its ability topass through quartz a t high temperatures. The only other gasesAbstr., 1907, ii, 690.21 Ibid., 772. ?2 Ibid., 22.23 949. a4 Ibid., 257. 26 Ibid. )' 166INORQANIC CHEMISTRY. 41by which the quartz is permeable are hydrogen and, possibly,carbon monoxide, and these are easily got rid of by mixing about5 per cent. of oxygen with the crude helium. The gaseous mixtureis introduced into the annular space between a quartz bulb and aplatinum cylinder surrounding it, and the apparatus is then heatedto 1100O. The bulb is evacuated, and very pure helium diffusesthrough into the interior. The process, although efficient, is veryslow.For the preparation of argon from air, F. Fischerz6 proposes thefollowing method.An iron tube is charged with powdered calciumcarbide mixed with 10 per cent. of calcium chloride, after whichit is evacuated? and heated to 800O; pure dry air is then admittedinto it, whereupon the oxygen and nitrogen are both absorbed,leaving argon.Group 2.There is comparatively little to report regarding the alkali metalsand their compounds generally, beyond what comes more suitablyunder other headings. The densities of the metals themselveshave been determined with great care by Richards and Brink27in order to correct the inconsistent values which have hithertoappeared in works of reference. They give the following valuesfor D20: Li, 0.534; Na, 0.9712; K, 0.8621 ; Rb, 1.532 ; Cs, 1.87;the last-mentioned is only an approximate value.A liquid alloyof sodium and potassium containing almost exactly 40 per cent. ofpotassium gave the value 0.919, which is nearly 1 per cent. lowerthan that calculated from the composition; there is therefore dis-tinct expansion on formation, but it is decidedly less than whatoccurs when either of the constituent metals fuses.Until recently, there was very little satisfactory information ob-tainable regarding the basic oxides of the alkali metals; many ofthe older statements were known to be entirely misleading, andchemists were left in doubt as to whether or not the oxides couldreally be prepared pure. The subject has now been placed on amuch more satisfactory footing by the publication of the results ofinvestigations by Rengade28 and by de Forcrand.29 The work ofcle Forcrand deals only with lithium oxide; he shows that themethods suggested by Troost (combustion of the metal in oxygen;decomposition of the nitrate by heat; ignition of the carbonate withcharcoal) yield impure products only.Lithia can be obtained,however, by dehydration of the hydroxide, LiOH (or its hydrate,LiOH,H20), by heating in a current of hydrogen to a temperatureof about 660-680O; at the lower temperature stated, the process is26 Abstr., 1907, ii, 344.28 %d., 1906, ii, 850 ; 1907, ii, 83, 45 j .Ibid., 258.]bid., 1907, ii, 615, 6842 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.very much slower than a t the upper one, when it is complete in anh0u.r. Lithium carbonate is more easily obtained pure, and formsa more convenient starting point than the hydroxide, for it also canbe completely decomposed under the conditions mentioned above ;the process is slower, but quantities of carbonate not more than agram in weight can be converted into oxide in about three hours a t780-800°.The product is a colourless, translucent, fused mass,which is distinctly volatile below 520°.Eengade's work doals with the oxides of the four other alkalimetals; his method consists in partly oxidising the particularmetal in a current of pure dry oxygen, and then removing theunchanged metal by prolonged distillation in a vacuum at not toohigh a temperature. He considers it probable that a suboxide isfirst formed, which decomposes into metal and oxygen.These oxides are crystalline solids, of density varying from 2-25(N+O) to 4.78 (Cs20).Those of sodium and potassium are whitewhen cold, but become yellow when heated; rubidium oxide is paleyellow when cold, and darker when heated; czsium oxide is red. Allof them decompose when heated above 400°, forming the metaland the peroxide. They react with liquid ammonia, forming hy-droxide and amide : M20 + NH, = MOH + MNH,. At a temperaturesomewhat below 200°, they react with hydrogen, forminghydroxide and hydride : M20 + H, = MOH + MH. I n the cold, theydo not react with carbon dioxide, fluorine, chlorine, iodine,or sulphur, but they do so with greater or less readiness whenwarmed. At the ordinary temperature, casium oxide takes fire inhydrogen sulphide; when heated, it unites with oxygen t o formthe peroxide, Cs,O,, and reacts with sulphur dioxide to form amixture of sulphide and sulphate.From a study of the absorption of oxygen by rubidium, Rengade 30describes the formation of the following higher oxides: Rb202(yellowish-white) ; Rb20, (black) ; Rb,O, (yellow).The causticising of sodium and potassium carbonates by slakedlime has been the subject of several investigations; these are chieflyof a physico-chemical nature, and only a few points need be notedhere.According to Le Blanc and No~otnS;-,~' there is no advantageto be gained in the technical process by working under pressure, butattainment of equilibrium may be hastened by efficient stirring,working a t a high temperature, and using excess of lime.Weg-scheider and H. Walter 32 have studied more particularly the condi-tions of formation of the double salt, Na&03,CaC0,, which crystal-lises out as penta- or di-hydrate and constitutes a source of loss;Abstr., 1907, ii, 458.32 Ibid., 259, 681, 682.31 Ibid., 22INORGANIC CHEMISTRY. 43they confirm the idea that its formation is facilitated by thepresence of excess of lime." Scheele's process " for obtaining sodium hydroxide direct fromchloride solution has been examined physico-chemically by Berl andAusterweil.33 It depends on the formation of an insoluble basicchloride of lead when salt solution is agitated with litharge, withregeneration of the litharge by means of slaked lime. With N -sodium chloride solution, the action is:2NaC1+ 4Pb0 + H,O = 2NaOH + PbCl,,SPbO.This basic salt is yellow; a white one, PbC1,,4Pb0,2H2O, is formedwith n1/2 solution. From results obtained in the course of thework, the authors conclude that lead oxide dissolved in sodiumhydroxide solution forms the compound NaHPbO,, with someNa,PbO, also if the soda solution is more concentrated than anormal one.As a method of obtaining pure copper, Vigourouxa recom-mends, first, the preparation of an acid solution of cuprous chloridefrom copper turnings, and precipitating the salt by filtering intoboiled out, but cold, water.The washed material is then decom-posed by means of excess of aluminium, used in large pieces; afterreduction is complete, the remaining aluminium is picked out, thecopper is washed with water, then hydrochloric acid, and again withwater; after being dried, it is reduced in a current of hydrogen.The existence of a peroxide of copper seems t o be placed practi-cally beyond doubt by several researches which have been madepublic.According to Erich Muller and Spitzer,35 a yellow-colouredperoxide is formed a t the anode when a solution of cupric hydroxidein very concentrated sodium hydroxide is electrolysed, or when thesodium hydroxide solution alone is electrolysed with it copperanode; from the loss of copper a t the anode, and the deficiency ofevolved oxygen with a given quantity of current, they deduce acomposition corresponding with the formula Cu,O,. L. Moser 36tried the effect of numerous oxidising agents on various coppercompounds, but only with hydrogen peroxide (in 10-30 per cent.neutral solution), acting a t Oo on freshly-prepared cupric hydroxide,did he succeed in obtaining a moderately stable peroxide; this wasin the form of a brown, crystalline powder.From the determina-tion of the ratio of active oxygen t o copper in the moist material(it loses oxygen on drying), he deduces a composition correspondingwith a peroxide, CuO,, but possibly there is also water correspond-ing with 1H20 (perhaps, therefore, the substance may be really acompound of a lower oxide with hydrogen peroxide). With dilute33 AMY., 1907, ii, 457.35 Ibid., 174.34 Ibid., 88.36 Ibid., 54944 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.hydrochloric acid, hydrogen peroxide is regenerated ; with concen-trated acid, chlorine is evolved.A similar substance is formedtransiently when sodium peroxide acts on cupric salt solutions.Erich Miiller 37 states that peroxide can also be obtained, as a redsolution or yellow precipitate, by acting with chlorine or bromineon strongly alkaline solutions of cupric hydroxide, although Moserwas unsuccessful with similar means. By oxidising solutions con-taining copper and tellurium by means of persulphate in presenceof potassium hydroxide, Brauner and B. KuzmaB have preparedseveral copper peroxidic compounds containing tellurium, for ex-ample, 2K20, Cuz03, 3Te0,, zH,O; they are very unstable.These results show fairly conclusively that there is a copperperoxide, but its exact composition has not yet been quite decisivelyascertained.Although the sulphides of silver and lead show so many strikingsimilarities, they apparently differ entirely from one another asregards their behaviour towards cuprous sulphide at high tempera-tures; K.Friedrich 39 finds that, after fusion, cuprous sulphide andsilver sulphide crystallise together in all proportions, but thatcuprous sulphide and lead sulphide crystallise out separately, prac-tically pure, and form a well-marked eutectic mixture.H. Biltz and Herms40 have prepared a number of salts of theacid HCuS,. The ammonium salt, which has long been known, isformed when cupric sulphide dissolves in ammonium polysulphidesolution, and can fairly easily be crystallised.The potassium,rubidium, and cmium salts can be prepared from the solution ofthe ammonium salt by precipitating with the alcoholic solution ofthe appropriate hydroxide. The salts are dark-coloured and crys-talline, and they decompose somewhat readily ; various more complexderivatives can be obtained from them.Evidence as to the molecular weight of cuprous salts has beenobtained by E. Beckmann 41 by employing the ebullioscopic methodwith solutions of cuprous chloride in quinoline; the results showthat in dilute solution the molecule corresponds with the formulaCuCl, but that in more concentrated solutions there is associationto form Cu2CI2. Several other interesting points with regard t ocuprous salts, and the relation of the cuprous salts to the cupricsalts, have also been published.According t o G. A. Barbieri,42when cuprous iodide is heated with cupric chloride the followingreaction occurs : 2CuI + 2CuCIz = 4CuCI +I2 ; similarly with cupricbromide. On the other hand, if cuprous chloride (or bromide) isdissolved in solution of alkali chloride and shaken up with a xylene37 Abslr., 1907, ii, 771. 38 lbid., 716. 59 ]bid., 951.4o Zbid., 262. 4' Ibid., 24. 4? ]bid., 462INORGANIC CHEMISTRY. 45solution of iodine, the reverse action takes place. Evidently, there-fore, the equilibrium 2Cn"+21' + 2C'+I, can be displacedthrough a very wide range, according to the conditions. Guichard 43finds that the action of anhydrous cupric chloride on hydrogeniodide, 2CuC1, + 4HI = 2CuI + I, + 4HC1, takes place even a t - 40'.The formation of cuprous sulphate in solution has been investi-gated by Foerster and Blankenberg.44 Copper acts on acid solutionof cupric sulphate to form some cuprous sulphate : CuSO, + Cu +Cu,SO,; the action is very slight at the ordinary temperature, butincreases with rise of temperature. In ammoniacal solution, a corre-sponding change takes place, and in this case conclusive proof ofthe existence of the cuprous compound is provided by the formationof a colourlesu, crystalline compound, Cu2S0,,4NH,,H,O.If theconcentration of copper is suitably chosen (not too great), solutionscan be prepared which are blue when cold, but become colourlesswhen heated, so that here the influence of temperature can bedirectly demonstrated.F. Herrmann 45 records an interesting ob-servation closely related to this. If ammonia in excess is added toa solution containing ferrous and cupric sulphates in equimolecularproportions (or preferably with a slight excess of ferrous), the ferroushydroxide reduces the cupric compound to cuprous, and a colourlesssolution is obtained, ferric hydroxide being precipitated : 2CuS04 +ZFeSO, + IONH, + 6H,O = [CU(NH~),]~SO, + 2Pe(OH), + 3(NH4),S0,.When the mixture is poured into cold dilute sulphuric acid, theoriginal sulphates axe regenerated, together with more ammoniumsulphate. The reaction provides a good method for preparing am-moniacal cuprous solutions for gas analysis. It is evident fromwhat is here stated that it is useless to employ ammonia as a reagentfor cupric salt in presence of excess of ferrous salt.Apparently cuprous metaphosphate is formed when the acid isfused with excess of copper, hydrogen being evolved, althoughcupric metaphosphate is found in the crucible after cooling; for ifthe fused mass is poured off from the unchanged copper andallowed to cool in absence of air, it is found that flakes of copperhave been deposited equal in weight to the copper contained inthe cupric compound.The cause of the different colours of colloidal solutions of silverhas been investigated by Gallagher,46 who concludes that the differ-ences are probably due to selective absorption of light, due to vary-ing degrees of coagulation, and depending also on the concentra-tion of the particles in the liquid and on the thickness of the layer.Changes of colour take place only under the influence of light,which probably induces coagulation, and the rate of change in-43 Abstr., 1907, ii, 689.44 Ibid., 89. 45 Ibid., 689. 46 Ibid., 8446 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.creases with increased light intensity. Many organic liquids pre-vent or retard change, apparently by preventing coagulation.Some interesting results regarding the nature of silver '' per-oxide," and the existence of the cation Ag", are published by G. A.Barbieri.47 By the action of potassium persulphate on silver pyro-phosphate, a compound is formed which contains active oxygenand silver in the proportion 1 : 13*12-14.89; i t is therefore a deriv-ative of the oxide A@, which requires the ratio 1 : 13.5.Sinceapparently it cannot give rise t o the formation of hydrogen per-oxide, and does not reduce lead peroxide, manganese dioxide, orpotassium permanganate in presence of concentrated nitric acid,the oxide Ago is not really a peroxide, but must belooked upon as a basic oxide; as a base, it is weaker thanAg20. It can apparently be formed from the latter by meansof potassium permanganate in alkaline solution, the following re-versible action taking place : Ag,O + 2KMn0, + 2KOH =+ 2Ag0 +2K2Mn04 + H20 (or Ago + MnO,' =+ Ag" + MnO,//). Dissolved inconcentrated nitric acid, silver nitrate reduces lead peroxide andbismuth tetroxide, as Ago would appear, in these circum-stances, to be a less powerful oxidising agent than these oxides.Group 11.For the purification cf commercial calcium, Muthmann, L.Weiss,and Metzger 48 recommend treatment with absolute alcohol, whichdissolves most of the calcium chloride with which the metal is con-taminated. A more efficient purification is effected by fusing themetal with calcium chloridefluoride to a fairly bright red-heat in aclosed iron bomb; this product is free from iron and chlorine, andcontains about 99.5 per cent. of calcium. The density was found tobe 1*41-1*42, which is distinctly lower than that stated by pre-vious observers. In the course of determinations of the heat of com-bustion in oxygen under pressure, it was found that the lime formedin the bomb had been fused to a clear, glassy mass if the metal wascontaminated with chloride to the extent of a t least 1 per cent.of chlorine; otherwise, the product was not even sintered.The use of calcium for the reduction of other elements from theirchlorides and oxides is discussed by the abovementioned chemists,and by F.M. Perkin.49. In some cases, fairly pure elements can beobtained, but in many the resulting products are alloys, &c. Apartfrom the latter fact, the method suffers from the drawback that theaction is often very violent, and that the lime produced is notfusible a t the resultant. temperature. Soddy 50 has shown that47 Abstr., 1907, ii, 767. 48 Ibid., 767. 49 Ibid., 952. Ibid., 251, 349lNORGANIC CHEMISTRY. 47strongly heated calcium is an excellent medium for the separationof the gases of the argon group from mixtures, since all the othergases are completely absorbed by the metal.Moissan showed that in the preparation of calcium carbide thelime always fuses before the carbide begins to form; Kahn61 hasnow found that this is not the case when barium or strontiumoxide is heated with charcoal, for a t the temperature of meltingplatinum a product is obtained which, although giving no indicationsof fusion, nevertheless contains carbide of the metal.He alsoshows 52 that these carbides, like calcium carbide, act as solventsfor carbon, dissolving varying proportions according to the con-ditions, and depositing graphite on cooling.The absorption of nitrogen by calcium carbide is found byPolzeniusz 53 to be accelerated considerably by the presence of easilyfusible oxygen-free calcium compounds, such as the halides.Thesame result is obtained by adding the halides of other metals, whichreact with formation of the calcium compounds ; bromides andiodides are, in general, more active than chlorides. When thecarbonates of the alkaline earth metals are heated with charcoal inan atmosphere of nitrogen, there is, according to Kuhling,54 amarked difference in the three cases as regards the amount ofcyanide and of cyanamide formed. With calcium carbonate atalmost 1400°, none of either is formed ; with strontium carbonatea t above 1200°, the yields are 1.4 and 0.8 respectively; whilst withbarium carbonate a t almost l l O O o , they are 23.4 per cent.and 1.6per cent. The yields are improved by the addition of chloride t othe mixture.As mentioned in last year's Report, calcium hydride, under thename of hydrolite, is now a commercial product, and its use f o r thepreparation of hydrogen is suggested. According to Prats Aymer-ich,55 the material, when treated with water, yields about 100 C.C.of gas per gram (about 18 cub. ft. per lb.); the hydrogen is freefrom ammonia and acetylene. Although the residual lime does notgive any indications of a phosphide when tested, there is a spon-taneously inflammable gas evolved when it is dissolved in hydro-chloric acid.The formation of crystallised double carbonates of calcium andthe alkali metals has been investigated by Butschli 56; in additiont o gaylussite, Na2CO,,CaCO3,5H,O, he has prepared the compoundsNa,CO3,CaC0,,2H,O, K,CO,,CaCO,, and 3K2C0,,2CaC0,,6H,0.The formation of sodium calcium carbonate takes place readily froma solution of sodium carbonate with amorphous calcium carbonate ;51 Abstr., 1907, ii, 460.54 Ibid., 166. 55 Ibid., 543.56 Ibid., 544, 616.52 Ibid., 166. 53 Ihi'bid., 86748 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.it takes place to a slight extent only with aragonite, and scarcely a tall with calcite in the course of thirty-six hours. The author usesthese differences for discriminating between the varieties of calciumcarbonate deposited in animal tissues.Several interesting points connected with the process of thesetting of plaster of Paris have been discovered by W.A. Davis.57He shows that in addition to gypsum, CaS0,,2H20 (monoclinic),the semihydrate, CaSO,,&H,O, soluble or quick-setting anhydrite,CaSO,, and the ordinary, or slow-setting, anhydrite, there is asecond dihydrate, which is rhombic, and probably a slow-settingsemihydrate. When gypsum is dehydrated by heating in a currentof air a t 98-130°, the rate of dehydration is less a t the beginning,as had already been observed, and Davis states that this is duet o a transformation taking place from the monoclinic to the rhombicdihydrate, which is the substance which really is dehydrated, andnot gypsum itself. It is also this variety which is formed, in thefirst instance, when either the semihydrate or soluble anhydritesets; afterwards, it slowly transforms into gypsum.In view of thenew facts, much of the work on this subject by van’t Hoff andhis pupils would appear to be rendered of doubtful value.A peculiar effect of potassium dichromate in retarding the rateof dissolution of magnesium in acetic acid is noted by Lohnstein 58;if the concentration of dichromate is increased beyond a certainpoint, action stops altogether, and the concentration necessary toeffect this increases with increasing concentration of the acid ; afterinhibition in this way, dissolution will re-commence, however, if themagnesium is made the anode of an electrolytic cell arrangement.The alkali salts and magnesium salts of strong acids destroy thepassivity.A new method of preparing crystallised magnesium oxide isdescribed by Houdard59; i t depends on t h e use of fused mag-nesium sulphide as a solvent.The two substances are heatedtogether in an electric furnace, and the crucible is allowed to coolslowly; the sulphide can be dissolved away with acid, leaving cubic,optically isotropic crystals of oxide. These dissolve only slowly inwarm hydrochloric or nitric acid, more rapidly in sulphuric acid.An interesting amino-compound, corresponding with potassiumzincate, is described by Fitzgerald 6o and by Frankk61 It is bestobtained, aB well-formed c?ystals, by acting with excess of potass-amide in anhydrous ammoniacal solution on the compound of zinciodide and ammonia. Its composition is represented by the formula(KNH),Zn,2NH3 ; in absence of ammoniacal salts, it is sparingly69 Ibid., 621.Ibid., 545. 61 xd., 768.67 Abstr., 1907, ii, 686. b9 Ibid., 769INORGANIC CHEMISTRY. 49soluble in ammonia; i t is rapidly acted on by water or diluteacids. When heated in a vacuum i t is stable as far as 160' a tleast, loses a good deal of ammonia a t 260°, and is more profoundlychanged a t higher temperatures.A peroxide of mercury was obtained by Bredig and Antropoff G2as a brown solid by the action of 30 per cent. hydrogen peroxideon mercury a t low temperatures, and in presence of traces of acid.The compound has been further investigated by Pellini,a who ob-tained i t as above, and also by the interaction of hydrogen peroxideand mercuric chloride and the equivalent quantity of potassiumhydroxide, all in alcoholic solution ; when prepared by the lattermethod, i t is less stable, rapidly decomposing with formation of mer-curic oxide.It is a brick-red powder, which shows no indications ofcrystalline character. It is decomposed slowly by water, givingbasic oxide, oxygen, and hydrogen peroxide; with acids generally, i tgives mercuric salt and hydrogen peroxide, but with hydrochloricacid chlorine is formed ; with potassium iodide, iodine is liberated ;potassium permanganate is decolorised. Unlike lead dioxide,therefore, it is a true peroxide.Vicario 64 points out that considerable discrepancies exist in thedata regarding the solubility of mercuric bromide, and shows thatthis is due to hydrolytic decomposition of the salt, which is verydecided on heating; oxybromides are formed, and may be obtainedas crystallised, yellow solids.A double salt, 2NaBr,HgBr2, isformed when sodium bromide is added along with the mercuricbromide, and a similar mixed compound is also formed by sodiumchloride; these are very soluble, and their solutions are not decom-posed by boiling.G ~ o u p IIZ.The variouscrystalline calcium borates formed from solution have been sfudiedby Meyerhofer and van't for the purpose of reproducingartificially certain of the complex borates found in nature; someof these were obtained, but the salts are of slight general interest.In the case of the lithium borates examined by Dukelskim in con-tinuation of his work on the potassium and sodium salts referred toin the last Report, three distinct borates appear to be formed a t 30°;of these, the monoborate, Li,0,Br03,1 6H20, and the pentaborate,Li,0,5Br03,10H,0, crystallise, but the diborate, which would bethe analogue of borax, was obtained only in an amorphous form, inwhich the amount of water could not be accurately determined.Regarding aluminium, it may be noted that a fair amount ofConcerning boron, there is very little to report.62 Zeilsch.Elektrochem., 1906, 12, 585.64 Ibid., 772. 65 Ibid., 542. 66 Ibid., 542.@ Abstr., 1907, ii, 954.REP.-YOL. IV. 50 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.work is recorded on the use of aluminium itself as a reducing agentfor the preparation of metals, alloys, Src.The behaviour of nitricacid and aluminium has been studied by van Deventer 67; the actionof dilute acid is slow, and is proportional to metal surface and t oconcentration of acid; chemically, i t is quite different from the actionwith zinc, since there is little or no formation of ammonia, althoughthere is some liberation of nitrogen ; the greatly predominatingaction is that expressed by the equation : Al+ 4HN0, = Al(NO,), +2H,O + NO.Houdard68 has succeeded in preparing a series of sulphur deriv-atives of aluminium, analogous to the spinels; three of these, whichhave been isolated more or less pure and well crystallised, belong tothe cubic system, as the spinels themselves do; these three havethe composition Mn(A41S2)2, Fe(AlS,),, and Cr(AlS,), respectively.The compounds are obtained by heating in a current of hydrogensulphide a mixture of aluminium turnings and the appropriatemetal, or its sulphide, contained in a carbon boat; the temperatureemployed is at first a red-heat, but later a white-heat.The result-ing mass is treated with water, acetic acid, &c.During the past year, there has been a fair amount of workdealing with the chemistry of thallium. As regards the relationof thallous compounds t o those of the alkali metals and of ammon-ium, Tuttron 6y has made an interesting comparison of sulphates andselenates in extension of his well-known work on this isomorphousgroup. Whilst the thallous compounds are rhombic and isomor-phous with the others, they do not show the same regular relation-ship regarding variation of crystal properties with variation inatomic weight of the metal; thallium is therefore not a memberof what, i t is suggested, might be called the “eutropic” seriescontaining potassium, rubidium, and czesium.0.Rabe 70 has further investigated the thallic oxide prepared byhim, as mentioned in last year’s Report. When heated, this oxideis much more stable than is generally supposed; it remains unde-composed, but is slightly volatile, a t GOOo, melts at about 720°, anddecomposes rapidly above 800°, forming thallous oxide and oxygen.The compounds of thallium with the sulphur group of elementshave been investigated by P6labon7l by means of fusion mixtures.The lowest sulphide thus formed is Tl,S, which floats as a separatelayer on any excess of metal present; a t the other end of the scale,two layers are also formed, one of sulphur, and the other of pentasul-phide, TI,S, ; a t intermediate stages, there is separation of TI8&.With selenium and tellurium, similar end-members of the series areAbstr., 1907, ii, 265.li8 Ihid., 468, 550.7‘ IBid., 770.69 l b d . ) 688.‘io l b f d . , 769INORGANIC CHEMISTEY. 51observed, but the intermediate stages are different. The formationof thallium sulphides in the wet way has been studied, along withother matters rela,ting t o the chemistry of thallium, by H a ~ l e y . 7 ~He treated thallous sulphide with sodium sulphide solutions con-taining extra sulphur, and then saturated with hydrogen sulphide.He concludes that the highest sulphide thus formed is T1,S3, andthat this forms a complete series of solid solutions with T1,S.Hehas also studied the products obtained by the simultaneous precipi-tation with hydrogen sulphide of solutions of thallous salts mixedwith compounds of arsenic and antimony, and finds that thalloussulphide forms inore o r less complete series of solid solutions witharsenious sulphide, antimonious sulphide, and antimonic sulphide.Wit,h arsenic sulphide, it forms a definite thioarsenate, Tl,AsS,, butno solid solutions. For the determination of thallium, Hawleyproposes the use of sodium thiostannate as precipitated, since thethallous salt, T14SnS4, is practically insoluble in water, and can bedried on a Gooch filter at 1 0 5 O without change.A very full and complete statement regarding the halogen com-pounds of thallium, the result of researches published from timet o time in preceding years, is given by V.Thomas,73 and particularsare given regarding various thallous salts by Stortenbeker.74Group IV.When Moissan succeeded in preparing artificial diamonds by theprocess of suddenly chilling the outer portion of a quantity ofliquid iron saturated with carbon and then allowing the core t osolidify gradually, it was supposed that the reason for some of thecarbon crystallising in an exceptional manner was to be found inthe very high internal pressure developed during the second partof the operation. This explanation is rendered doubtful, however,by the results of experiments conducted by C.A. Parsons.75 Coresof carbon, or of carbon and iron, suitably enveloped, were subjectedto the action of exceedingly strong electric currents with simul-taneous application of direct pressure, which, in some instances, roseas high as 100 tons t o the sq. inch; s o f t graphite was the usualform in which the carbon was found on cooling, and in no instancewas there any distinct indication of the formation of diamond,although the pressures employed were probably higher than thoseobtainable in Moissan’s process. The latter’s views are also criti-cised by van Deventer 76 from the theoretical standpoint.An interesting study regarding the direct union of carbon andi2 Abstr., 1907, ii, 460, 770.75 Ibid , 762.73 IbicZ., 547.76 Ibid., 456.Ibbid., 770.E 52 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.nitrogen, and the decomposition of cyanogen, has been made by If.Berthelot.77 From his results, it appears that carbon and nitrogen,if both are perfectly pure, show no tendency to unite when heatedwith each other, even up t o the temperature of the electric arc.Previous results, which have seemed to indicate the contrary, weredoubtless obtained with impure materials, especially with impurecarbon, since it is exceedingly difficult to prepare this elementpure, and therefore it is advisable that natural diamond should beused.The most important impurities are, in the first place,hydrogen compounds, which give rise to the production of acetylene,and so of hydrocyanic acid; in the second place, metallic com-pounds, which give rise to cyanides.If pure carbon and nitrogencould unite, equilibrium should be attained in the direct decom-position of cyanogen, but when this gas is submitted to the actionof powerful electric sparks it is apparently completely aecom-posed; the solid deposited is a mixture of polymerisation productsand carbon, and the residual gas is pure nitrogen.Two new metal-carbonyl compounds have been described. Fromthe compound Fe,(CO), (which, as stated in the Report for 1905,is formed on exposure of Fe(CO), t o bright sunlight), Dewar andH. 0. Jones 78 have obtained the tetracarbonyl, Fe(CO),. When thefirst-mentioned compound is heated with various liquids in an atmo-sphere of carbon dioxide to a temperature of 50-90°, intenselygreen solutions are formed; from the solution thus formed withtoluene, green crystals of the new compound can be obtained.Ifthe solid is heated alone or in solution, it decomposes a t or below140° with deposition of iron and liberation of carbon monoxide.I t s molecular weight appears to be very high, from the very slightdepression of the freezing point which it brings about in benzenesolution.The second new carbonyl compound, or, rather, a derivative ofit, was obtained by von Bartal79 in the course of an investigationof the action of carbonyl chloride on the aluminium halides. Whenaluminium iodide is fused at about ZOOo and treated with thevapour of carbonyl chloride until it has gained in weight t o theextent of 25 per cent., the solid product which forms on coolinggives up iodine and unchanged iodide when repeatedly digestedwith carbon disulphide, and leaves a brown, amorphous powder;the composition of this corresponds with the formula Al,(CO),Cl,I.The solid decomposes when heated to about 300°, losing aluminiumhalides, and leaving a black residue containing aluminium andcarbon, but no halogen. From the general behaviour of the sub-stance, von Bartal concludes that the original substance consists77 Abstr., 1907, ii, 257.78 Ibid., 266. i9 Ibid., 957INORGANIC CHEMISTRY. 53of a double compound, Al,(CO~,AlCl,I. One of the products of theaction of carbonyl chloride on aluminium bromide is carbonylchlorobromide, COClBr, which von Bartal obtained pure as a prac-tically colourless liquid of disagreeable odour, and boiling a t 25O.The reduction of carbon dioxide t o formaldehyde has been effectedby Fenton80 by passing a rapid stream of the gas through purewater in which rods of amalgamated magnesium are immersed.The amount of aldehyde formed is small, but the proportion isincreased in presence of certain substances, such as ammonia orphenylhydrazine.A number of complex carbonates, including acid salts, have beenprepared by various workers.T. B. Wood and H. 0. Jones81 haveobtained potassium cupn'c carbonates (previously described byReynolds) by the action of a mixed solution of potassium carbonateand bicarbonate on basic cupric carbonate. From the behaviourof this salt (and also of potassium cobaltous carbonate) on electro-lysis, the authors conclude that these double carbonates give in eachcase a complex ion, M(CO,),", in solution.Raikow82 has investi-gated the formation of carbonates by the action of carbon dioxideon suspensions of bases in water. (In some cases, the suspensionswere obtained by treating a normal solution of a salt of the metalwith one-fifth of the equivalent of alkali, and they would thereforecontain basic salts and not hydroxides.) I n the great majority ofcases, the quantity of carbon dioxide taken up corresponded withthe formation of normal salt, but in some cases only basic saltscould be found, whilst in others acid salts were obtained; twounstable compounds belonging to a new type of acid carbonatewere produced, N!i,H2(CO,), and Cu3H(C03),, from nickelous andcuprous hydroxides respectively.I n order to prepare crystallised silicon free from the small quan-tities of iron with which it is found always t o be associated whenobtained by heating potassium fluosilicate with aluminium in a claycrucible, Vigouroux 83 recommends that the impure material befinely powdered and digested for some hours with diluted hydro-fluoric acid, then washed, and heated with concentrated sulphuricacid; this process of purification is to be repeated until a sampleyields no residue when heated with a mixture of nitric and hydro-fluoric acids.Methods for the preparation of pure titanium tetrachloride aregiven by Vigouroux and Arrivaut 84 and by Ellis.85 The formerstart from commercial ferrotitanium, either using it directly or,All operations are conducted in platinum vessels.*O Trans., 1907, 91, 687.g2 B i d ., 1'70, 171.84 Ibid., 97, 270.8' Ahsly., 1907, ii, 621.P3 Ibid., 82.85 Ibid., 27054 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRYpreferably, first removing the greater part of the iron by means ofhydrochloric acid, The material is heated in a porcelain tube, anda current of dry chlorine is passed over it, which causes incandes-cence. Most of the ferric chloride which is formed condenses inthe cooler part of the tube (which must be wide to prevent choking),and the tit,anium compound is condensed by means of air and watercondensers ; the filtered liquid is then fractionated.Ellis startswith rutile, which is first powdered (this is easily effected if themineral is strongly heated and then chilled), then dried, mixedwith aluminium, and the mixture ignited by means of a mag-nesium fuse. The resulting material is transferred t o a combus-tion tube, and treated with dry chlorine. The condensed productis condensed and fractionated ; chlorine and silicon chloride firstpass over; the amount of the latter may be considerable, dependingon the amount of silica and silicate present with the rutile.pertitanic acid ” is discussedby Faber 86; he finds that its solutions behave so much like solutionsof hydrogen peroxide that the existence of sexavalent titanium com-pounds might be considered dubious. He has, however, succeededin preparing two new yellow compounds which he believes giveconclusive evidence of such existence.One is an acetate deriva-tive, which is so explosive that it could not be properly analysed;the other is a phosphate which corresponds with the formulaTi(OH),PO,. The author assumes that the titanium has becomesexavalent by the direct addition of two hydroxyl groups; in thatcase, the compound should not regenerate hydrogen peroxide whendecomposed, but on this point he gives no information.The investigation of zirconium salts by A. Rosenheim andothers 87 is continued. As a rule, i t is found that basic compounds,salts of the radicles (ZrO) and (Zr203), are obtained by crystallisa-tion from solutions in acids; a considerable number of such salts,simple and double, and derived both from organic and inorganicacids, are described (chlorides, nitrates, sulphates, oxalates, tar-trates). In circumstances where hydrolysis cannot occur, however,and also in some special cases even when water is present, normalderivatives are obtainable. For example, when zirconium tetra-chloride is heated with formic, acetic, or propionic acid, the wholeof the chlorine is evolved as hydrogen chloride, and normal formate,acetate, or propionate is formed.The normal acetate under-goes gradual hydrolysis when exposed t o air which is dried by sul-phuric acid, forming zirconyl acetate; in ordinary air, thisacetate undergoes complete hydrolysis. Zirconium chloride reactswith many organic compounds, for example, with many esters, t oThe question as to the nature ofes Abstr , lQ07, ii, 557 Ibid., 27INORGANIC CHEMISTRY.55form either direct additive products or derivatives in which halfof the chlorine is replaced by organic groups ; thus, salicylaldehydeyields the compound ZrCl,(O*C,H,*COH),. The authors find thatmany of the published data regarding the basic zirconium salts areerroneous; this is confirmed also by Arthur Miiller 88 from hisexperience in preparing colloidal zirconium hydroxide from thenitrate.Bellncci and Parravano 89 have prepared hydrosols of plumbicacid (hydrated peroxide) by dialysis from potassium plumbate; theratio K20: PbO, may be reduced thus to 1.87: 98.13. The liquidmay be taken to a syrupy consistency on the water-bath withoutcoagulation, and the hydrosol is fairly stable.When added to purewater, it causes no appreciable lowering of the freezing point. Thesubject has also been studied by Parravano and G. Calcagni.The well-known changes which take place on heating the productsof the partial oxidation of lead sulphide, and which play such animportant part in the metallurgy of lead, have been very fullystudied by Schenck and Rassbach,go who show that the process ismore complex than has generally been assumed. This is due tothe fact that reversible actions are involved, and from the investi-gation of the equilibrium conditions the authors conclude that thefollowing four equations represent the chemical reactions whichactually occur :PbS + PbSO, * 2Pb + 2S0, ; PbS + 2Pb0 + 3 P b + SO, ;P b S + 3PbS0, * 4Pb0 + 4S0, ; P b + PbSO, * 2 P b 0 + SO,.Only one compound of lead and selenium, namely, PbSe, can beobtained by fusing together the two elements, although, when excessof selenium is used, the lower of the two layers formed containsnearly twice as much selenium as corresponds with the mono-selenide.This is shown by P6labon91 t o be due merely to thesolubility of the selenium in the fused monoselenide; the upperlayer is practically pure selenium.Descriptions of thorium compounds are given by Matignon andD e l & ~ i n e , ~ ~ the principal being the tetrachloride and oxychloride, thenitride (TI@,), and the hydride (ThH,).Group V .The synthetic production of ammonia under the influence ofelectric sparks has been studied by Briner and E.Mettler.93 Fortheir experiments they prepared the gaseous mixture of the elementsby passing dry ammonia over electrically heated spirals of nickel,Ahstr., 1907, ii, 272,Ibid., 647, w Ibid., 179, 83 IBid., 342,a9 Ibid., 86, 87. Ibid., 546, 61956 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.platinum, or iron, and subsequent treatment with sulphuric acid.The proportion of ammonia formed, which amounts t o only 3-4 percent. at the ordinary temperature, increases with falling tempera-ture, and the action is nearly complete at the temperature of liquidair. The influence of pressure was also studied, and found to bepeculiar, since, within the working range of 20-800 mm., there wasfound to be (at 100 mm.) a marked maximum in the efficiency withregard t o the energy expended; the producfion at this pressure was0.17 gram of ammonia per kilowatt hour.Another method for the synthetic production of ammonia formsthe subject of a patent by Kaiser.94 His process depends on thealternation of the action of hydrogen on calcium nitride, whichyields ammonia and calcium hydride, with that of nitrogen on cal-cium hydride, which also yields ammonia and regenerates calciumnitride; it is advisable that the solid material should be finelydivided and expose a large surface.The most suitable temperatureis between 200° and 400°, although the reaction sets in about 1 5 0 O .I n the case of the elements magnesium, titanium, boron, cerium,molybdenum, and tungsten, either a nitride cannot be formed bydirect union or else the nitride does not yield ammonia with hydro-gen.Cerium nitride does yield hydride and 'ammonia, and thenitride can be regenerated by nitrogen, but the gases require to bepurer than is practicable for a technical process.There has been considerable discussion recently as t o the formationof a definite ammonium amalgam, and the general tendency isapparently in favour of its existence.The investigation of hydrazoic acid (azoimide) and some of itsderivatives has been continued by L. M. Dennis and Miss Isham.95The pure acid was prepared by the distillation of small quantitiesof the potassium compound with somewhat diluted sulphuric acid,the vapours, after drying, being condensed by means of liquid air ;the product thus obtained was proved by analysis to contain 99.94per cent.of the acid. The boiling point given by Curtius, 30°, wasconfirmed, and the freezing point was found to be - 8 O O . Thevapour density was determined by Victor Meyer's method, and foundto agree with the simple formula, HN,. The greatest care had tobe exercised in working with the acid, and considerable use of liquidair had to be resorted to, so as to freeze it and thus facilitate itsmanipulation. For example, in the first attempts to determine thevapour density (before freezing was resorted to) the material alwaysexploded violently when the containing bulb was broken, and evenwith so small a quantity as 0.011 gram both vessels of the apparatuswere completely shattered. The copper and zinc salts form com-Abrtr., 1907, ii, 862, * Ibid, 165, 2551NORGlANIC CHEMISTRY.57pounds with ammonia and with pyridine, CuN,,2NH3, &c.; thecobalt and nickel salts unite with pyridine in higher proportions.In connexion with the quantitative determination of azoimide, it ispointed out that when treated by Kjeldahl’s method it yields one-third of its nitrogen as ammonia.show that azoimide may be formed in appreciable quantity duringthe oxidation of hydrazine, for example, by the action of ammoniummet avanadat e.H. B. Baker and Mrs. Baker97 have made the interesting dis-covery that nitrogen trioxide can be obtained in the gaseous formby volatilisation of the liquid into an atmosphere of nitrogen whichhas been dried as completely as possible, so that apparently thedissociation into nitrogen peroxide and nitric oxide (like that ofammonium chloride, &c.) takes place only in presence of moisture.The evidence is provided by vapour density determinations accord-ing to Victor Meyer’s method; these, under the special conditionsindicated, gave numbers varying from 38 to 62, and, since thetheoretical number for N,03 is 38, i t is therefore to be presumed thatpolymerisation takes place with formation of N,O, molecules.According to Manchot and Zechentmayer,”6 and G.von HiifnerFgi t appears that the absorption of nitric oxide by solutions of ferroussalts (and also of nickelous, cobaltous, and manganous salts) takesplace to an extent such that the ratio NO : Fe“ approaches, but doesnot exceed unity, provided due allowance is made for the absorp-tion due to the water itself.Apparently, therefore, there is somesort of compound formed; the union is so slight, however, that theordinary absorption laws hold. According to Kohlschiitter and M.Kutscheroff ,1 the absorption by ferrous chloride is nearly doubledif solution in 30 per cent. hydrochloric acid is used in place ofaqueous solution, although the effect is diminished rather thanincreased if 10 per cent. acid is used.Two papers by Boeseken deal with the properties of pure ordin-ary phosphorus, and the change of the latter into the red modifica-tion. According t o him, the pure substance is perfectly white, andremains so if kept in the dark in evacuated tubes, but it soon becomesyellow on exposure to light; the common yellow phosphorus, whichhas been melted under water, always retains a considerable quantityof moisture, and has lower density and a lower melting point thanthe pure substance. To obtain the latter, he heats phosphorus withchromic acid solution, washes, dries in a vacuum, first a t 40°, thenat 80°, and lastly distils.Boeseken finds that in evacuated tubesaluminium chloride brings about the change to red phosphorusQ7 Trans., 1907, 91,’lSSZ.A. ’CV. Browne and Shetterlygs Ahtr., 1907, ii, 863. D8 Abslr., 1907, ii, 93.Ibid., 562. ]bid., 267. Ibid, 343, 76058 ANNUAL HEPOR~S ON THE PROGRESS OF CHEMISTRY.below 100°, especially if phosphorus trichloride is present t o act assolvent.To explain such catalytic changes, he holds that it is neces-sary t o assume that the transformation is preceded by a breakingup of the P, molecule, and that the products of this dissociation(Pz o r P) thereupon polymerise to form the more complex moleculeof the red variety; the dissociation is a very slow action, and it isthis which is accelerated by the various catalytic agents. To demon-strate this change experimentally, Zecchini 3 heats from 10 C.C. ofdried phosphorus in a glass tube immersed in a bath of sulphuricacid a t 180°, and then drops in a small crystal of iodine, whereuponpractically the whole of the phosphorus undergoes transformation.According to Jungfleisch,4 pure oxygen a t atmospheric pressureoxidises dry phosphorus directly t o phosphoric oxide only; but, ifthe concentration is very considerably diminished by lowering thepressure or mixing with inert gas, then phosphorous oxide also isformed, along with a yellow lower oxide, P,O.The process can beso regulated as t o produce crystals of phosphorous oxide. This isexceedingly inflammable, and, on admission of air or oxygen, takesfire before any phosphorus which may be present.An interesting method of completely decomposing phosphates, andvolatilising all the phosphorus compounds formed, is described byJannasch and Jilke.5 It consists in heating the substance in astream of chlorine laden with vapour of carbon tetrachloride.Theexperimental work so far completed deals only with ammonium andmagnesium phosphates ; with them the process of volatilisation iscomplete in the course of several hours.In connexion with an investigation of the changes which takeplace on the heating of ammonium salts, Dehn and Heusee findthat the phosphates and arsenates give off water and ammoniasimultaneously from the first, and that the residues obtained asintermediate products are of indefinite composition. On this accountit appears highly probable that many so-called compounds which arestated to have been prepared in this way are really complex mix-tures.Hewitt and Winmill7 find, from the results obtained by theebullioscopic method with solution in carbon disulphide, that arsenicdi-iodide has the composition As$,.As stated by Bamberger andPhillip, who first prepared it, the decomposition by water (3As.$, =4As1, + 2As) is not, complete; a complete decomposition in this sensetakes place, however, when the compound is treated with pyridine.Apparently ortho-arsenic acid does not exist as a solid having thecomposition H,AsO, ; according to Baud,* the highest solid hydrate't Tmns,, 1907, 91, 062.3 Abstr., 1907, ii, 681, 4 B i d . , 761. Ibid., 864.Ibid,, 766, Abstr., 1907, ii, 76INORGANZC CHEMISTRY. 59derived from the pentoxide, namely, 4H,O,As,O, (presumablyH,AsO,,H,O), effloresces to form pyro-arsenic acid, H4As,07,directly, no intermediate compound being obtainable.The method of preparing antimony pentafluoride, by the actionof hydrofluoric acid on the chloride, has been improved, and thesubstance itself investigated, by Ruff and other^.^ It forms anumber of interesting additive products.With chlorine it doesnot unite; with bromine it yields a mass which possibly containsthe compound SbF,Br ; with iodine it forms two compounds, (SbF,),Iand SbF,I. It dissolves sulphur with formation of a blue solution,from which the compound SbF,S can be isolated. With a smallquantity of water it unites t o form the solid hydrate SbF,,2H20,which is soluble in water; the solution is not very readily actedon by reagents such as hydrogen sulphide, potassium iodide, &c.\‘tell-defined, crystalline double sulphates of antimony and themetals of the alkaline earths, and silver, have been prepared byKiihl10 from solutions of the constituent salts in concentrated sul-phuric acid.Those with metals of the alkaline earths have thecomposition MSb,(SO,),,GH,O ; the silver salt is similar, but anhy-drous.There has been a fairly considerable amount of new work dealingwith vanadium. The preparat.ion and properties of the element itself,and also of columbium and ta,ntalum, are described by W. Muth-mann, L. Weiss, and R. Riedelbauch ll; the method of preparationused is a modified ‘‘ thermite ” process, in which a (( mixed metal ”obtained froin the rare earths is employed in place of aluminium.A considerable amount of information regarding columbium and itsproperties is also given by W. von Bolton,l2 who prepared the pureelement by reducing the pentoxide with aluminium, and volatilisingthe excess of aluminium, and other impurities, by heating electricallyin a vacuum for several hours.The values given for some of thephysical properties differ considerably from those of the precedingauthors.The preparation of pure hypovanadic acid, and of a considerablenumber of compounds derived from it, is described by Gain.18 Hisstarting point is the mixture of oxides (V,O, and V,04) left whenammonium metavanadate is calcined ; this is treated with saturatedsulphurous acid solution, and a blue solution is thus obtained, fromwhich the compound 2V,O4,3S0,,1O~T,0 can be crystallised. Thisloses sulphurous acid when boiled with water, and hypovanadic acid,H,V205, is deposited as a pale reddish crystalline powder.From this,and from the blue solution, a series of blue crystalline vanadylThey are all decomposed by water.Abvtr., 1907, ii, 98 Ibid., 627. B i d . , 781.‘2 bbid., 478 ]bid,, 38, 97, 658, 62760 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.sulphattes can be obtained by the action of sulphuric acid. Com-pounds more o r less similar to these are also obtainable from selenic,orthophosphoric, and ortho-arsenic acids. The blue solution alsoyields a series of double sulphites when it is mixed with solutions ofthe acid sulphites of ammonium, thallium, and the alkali metals, andthen evaporated at a low temperature. Mawrow,14 by acting onvanadic acid with hypophosphorous acid, has prepared a di-vanadylhypophosphite, Vz0,(H,P0,),,2Hz0, from which, by the action ofalkali, di-hypovanadates are obtained, f o r example, the ammoniumsalt, ( NH,),V,O9,3H,O.Group VI.F.Fischer and Hans Marx,lS in continuation of work referred toin last year's Report, give further particulars regarding the produc-tian of ozone and hydrogen peroxide when air or oxygen is blownover a glowing Nernst-filament; the yield of ozone increases withrise of temperature of the filament, but falls with rise of temperatureof the gas current; the shape of jet used also influences the yield.For air, the maximum yield was 0.13 per cent. of the oxygenpresent; with oxygen a better yield is obtained by using a slowcurrent. When moist gas is used, the yield of ozone diminishesconsiderably, but hydrogen peroxide is then formed also.I f aglowing filament is plunged into liquid oxygen, the yield of ozonedepends on the duration of the experiment; as much as 3-91 percent. was obtained after ten hours.Some interesting results regarding the preparation of ozone elec-trolytically are given by F. Fischer and Massenez.16 By suitablearrangements of the apparatus and conditions employed, they havesucceeded in obtaining products containing as much as 28 per cent.of ozone by weight. Various types of anode were tried; that whichgave the best result was formed from a platinum tube coated withglass, with a narrow slit cut through this coating so as to expose avery small surface of platinum. The anode was kept cold by acurrent of calcium chloride solution cooled to -14O, wliilst theelectrolyte itself was kept a t Oo.The most suitable electrolyte issulphuric acid of concentration such that the layer of greater con-centration formed a t the anode becomes acid of maximum conduc-tivity. The surface of the anode should be kept as smooth aspossible.According to E. Merck,17 a good yield of hydrogen peroxide canbe obtained from barium peroxide, suspended in water, by theaction of carbonic acid, prmided the barium peroxide is kept inl4 Abstr., 1907, ii, 782.'@ Zbid., 162, 254.l5 Ibid., 163, 340.l 7 Tbid., 859INORGANIC CHEMISTRY. 61excess ; with excess of carbonic acid, very little hydrogen peroxide isobtained owing t o the formation of fairly stable barium percarbon-ate, BaCO,.This saltl, prepared a t low temperature from eitherhydrated or anhydrous peroxide, can be used for the preparationof hydrogen peroxide, by treating i t with the appropriate quantityof an acid which forms an insoluble barium salt.From a study by A. Fischer I* of solutions prepared from purehydrogen peroxide, it appears that very slight concentrations ofsulphuric and hydrochloric acids are highly efficient in retardingdecomposition; phosphoric acid is less effective, and boric acid stillless so; oxalic acid, so far from decomposing the peroxide, is, inconcentrations of 0-1-2 per cent., a more efficient preservative thaneither hydrochloric or sulphuric acid.The peculiarities exhibited by molten sulphur, and the differencesobserved in different varieties of precipitated sulphur, now seem t obe satisfactorily explained, as a result of the investigations by A.Smith and his collabmat~rs.~~ The conclusions arrived at are thatwhen sulphur is fused, two modifications result, which are distin-guished as SA and S,, and these are dynamic isomerides.20 SA iscomparatively mobile, and is light in colour ; S,, is viscous and dark.The proportion of S, is small a t low temperatures, but increases withrising temperature; if the temperature is raised rapidly, there maybe a decided lag, so that some time may elapse before equilibriumis established.The rate of transformation can be greatly retardedby certain agents, such as sulphur dioxide or hydrochloric acid, butthis effect can be reversed by others, such as ammonia.Advantageis taken of this in determining the state of equilibrium a t any giventemperature ; equilibrium is established rapidly with the help ofammonia, then a retarding gas is passed in, and the liquid sulphuris rapidly chilled in water. The solid obtained from SA is crys-talline, arid soluble in carbon disulphide, whilst that from S, isamorphous and insoluble. When ordinary sulphur is heated, thereis always considerable retardation, owing t o the invariable presenceof sulphur dioxide in sulphur which has been exposed to air.(According to Moissan,21 even sulphur which has been melted andcooled in a vacuum cannot be obtained free from bubbles of hydrogensulphide and sulphur dioxide when i t is remelted; these gases areformed from traces of water which it is almost impossible to remove.)l8 Abstr., 1907, ii, 161.20 3’.Hoffmaun and R. Rothe (Abstr., 1907, ii, 539) claim that in this mattertheir views have been adopted by Smith and his colleagues without acknowledg-ment ; but this charge is satisfactorily rebutted by the latter (Zeitsch. physiknl.Chem., 1907, 61, 207).l8 Ibid., 20, 451, 757.91 Abstr., 1907, ii, 34162 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The amount of S, present in liquid sulphur at 114.59 a t whichtemperature i t is in eluilibrium with solid S,, is only 3.7 per cent.As regards precipitated sulphur, the conclusions drawn are thatthe sulphur separates first in liquid form as S,, which, however,changes more or less rapidly to SA, and ultimately to S,.The rateof transformation varies greatly with the nature of the liquid incontact with the liberated sulphur. The soluble varieties of precipi-tated sulphur are merely S,; the insoluble varieties are those inwhich solidification has taken place before any great proportion ofSp has been transformed into SA.Paternb and Mazzucchelli 22 have investigated the blue variety ofsulphur described by Orloff, and have also examined many cases offormation of blue colorations in which sulphur compounds are in-volved. They conclude that although there may be some cases inwhich the coloration is due to the presence of this variety of sulphur,as a rule there is no reason t o assume that this is so ; certainly therecan be no free sulphur involved in the case of ultramarine, sincethe blue coIour persists after the substance is heated to bright rednessfor some time.For the preparation of hydrogen sulphide, Fonzes-Diacon *3 recom-mends the method of dropping water on solid aluminium sulphide;this is prepared by igniting, by means of a magnesium ribbon fuse,a mixture of sulphur and aluminium in a crucible.The synthesis, and the dissociation, of hydrogen sulphide havebeen the subject of investigation by Milbauer 24 and Preuner.25 Thepapers are chiefly of physico-chemical interest; but, with regard t othe first-mentioned, i t may be noted that the action is found to beaccelerated by platinum black and by phosphorus, the effect in thelatter case being due, presumably, t o the actions : ( a ) P,S, + 813, =ZPH, +- 5H,S, (6) 2PH, + 4S, = P,S, + 3H,S.Metallic sulphidesappear to be without effect.The properties of liquid hydrogen sulphide, and its character asa solvent, have been examined by Magri. Under atmospheric pres-sure i t boils a t - 6Z0 and freezes at - 8 3 O ; its density is slightlyless than that of water. It does not dissolve the salts of strongbases, but is a solvent for many of the compounds formed by non-metallic elements among themselves; some of these solutes increasethe conductivity t o some extent.The precipitation of metallic sulphides from solutions of theirsalts, by means of hydrogen sulphide, forms the subject of severalpapers by Padoa and Cambi,27 Bruner,28 and Glixelli.~g The first-22 Abstr., 1907, ii, 451.25 Ibid., 86i.za Ibid., 453. n lbid., 86.28 l b i d . , 349.23 Ibid., 164.29 lbid., 868.% Ibid., 163INORCIANIC CHEMISTRY. 63named authors concern themselves chiefly with the pressure of hydro-gen sulphide necessary for the precipitation of sulphide from acidi-fied solutions, cadmium chloride, zinc sulphate, zinc chloride, andferrous sulphate, and show that these pressures increase with increas-ing acidity. The two other authors named deal only with theprecipitation of zinc sulphide, and their results corroborate eachother. They find that the circumstances are complex; that thenon-precipitation of zinc sulphide, from dilute acid solutions ofordinary zinc salts saturated with hydrogen sulphide, is due to astate of “false equilibrium,” and not t o the reversibility of theaction (as is generally supposed), since the amount of zinc in solu-tion is grea€ly in excess of what would be obtained by the actionof such an acid solution on zinc sulphide; after a “ period ofinduction,” the duration of which increases with increasing acidity,precipitation sets in, and proceeds at a rate which also depends onthe acidity.There are apparently two modifications of zincsulphide, which differ greatly as regards solubility ; for example,the sulphide precipitated from alkaline solution is nearly fiftytimes more soluble than that precipitated from acid solution. Theabove results indicate that in this matter zinc is quite analogoust o cobalt and nickel, only in these cases the period of induction ismuch longer.The quantitative composition of the products of combustion ofsulphur in air and in oxygen has been studied by Kastle and&J.~Hai*gue.~~ With air, the proportion of sulphur converted intosulphur trioxide rises as high as 7 per cent., but with oxygenit averages only about 2.7 per cent.; in neither case is the ratioappreciably affected by the presence of moisture.The authorsassume that the higher yields with air are due t o the formation ofnitrogen oxides which act as carriers; but since, with mixtureswhich contain less nitrogen than air does, the yield is lower thanwith air, i t would appear not un!ikely that it is largely a question oflower temperature benefiting the yield of sulphur trioxide.The chemistry of the lead-chamber process has been dealt with byRaschig,3l Lunge and Ber1,3? and I n g l i ~ .~ ~ . The first three papersform a continuation of the discussion referred to in last year’sReport, and need not be Azrther referred to. Inglis’s contributionis a further instalment of his investigation into the loss of nitre;he conchides that the loss is very largely in the form of nitric oxideand peroxide, loss in the form of nitrous oxide being less than 10 percent., and that in the form of nitrogen itself doubtful.The reduction of concentrated sulphuric acid by hydrogen gas is3o Abstr., 1907, ii, 861.32 Ibid., 863.31 Ibid., 455, 863.33 Ibid., 61364 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.an action which is sometiaes unjustifiably ignored in some branchesof work; it has been studied very fully by R l i l b a ~ e r .~ ~ He finds thatpure acid is almost unaffected a t the ordinary temperature, but thatthere is a distinct action at higher temperatures. The catalyticeffect of numerous substances was examined a t 174O; the action isaccelerated by a considerable number, including sulphates which aresoluble in the acid, and notably so by the metals of the platinumgroup; it is retarded by many substances which are insoluble inthe acid. Many of the substances which were tried were found t oundergo reduction themselves, but some are oxidised, the mostnoteworthy cases being ferrous sulphate and mercurous sulphate.An extended investigation of the action of alkalis on solutionsof the sulphates of metals of the iron group, &c., has been made byPi~kering.~S I n only two of the cases examined (magnesium andmanganous sulphates) was hydroxide precipitated directly ; in allothers a basic salt of definite composition was first precipitated, t o befurther acted on by continued addition of alkali, with formationof a more basic salt or of hydroxide.The formation of sodium thiosulphate from sulphite and sulphurhas been examined by Kremann and Hiittinger36 to see if i t wouldthrow any light on the retarding effect of glycerol, glucose, &c.,on the formation of sodium siilphate from sulphite and oxygen.Since the retarding agents named have no influence on the forma-tion of thiosulphate, i t is concluded that in the other case theyexercise their effect on the oxygen and not on the sulphite.Some interesting results with regard to the electrolytic formationof persulphuric acid and persulphates have been obtained by ErichMuller and Schellhaas.37 They find that the yield of persulphuricacid is very injuriously affected by the presence of Caro’s acid; thisis formed from the other by hydrolysis (H2S20, + H20 = H,SO, +€12S0,), and undergoes decomposition a t the anode, presumably bythe action of discharged hydroxylion : H,SO, + 20H = H,SO, +H,O+O,.The authors show that this loss of efficiency can begreatly diminishgd (1) by raising the anode potential by addition ofsome such substance as hydrofluoric acid; (2) by immediately re-ducing the Caro’s acid, using some reducing agent which does not actsimilarly on persulphuric acid, for example, sulphurous acid; (3) byremoving the persulphuric acid almost completely in the form of apersulphate which is practically insoluble in the liquid, such as theammonium salt in very acid solution.By means of the secondmethod, a current efficiency of more than 90 per cent. may beattained.34 Abstr., 3907, ii, 252.36 Abstr., 1907, ii, 758.35 Traias., 1907, 91, 1981, 1988.37 Ibid., 539INORGANIC CHEMISTRY. 65Much work dealing with complex derivatives of chromicoxide has been carried out by J. Olie, jun.,Ss A. Colson,39R. F. Weinland and T. Schumann,40 P. Pfeiffertl A. Wernerand J. D u b ~ k y , ~ ~ and N. Bjerrum.43 The papers of Olie dealwith chromic chlorides, especially the hydrates of the greensalt; the proportion of the total chlorine which is precipitatedby silver nitrate has been investigated, and it is found that thisis considerably affected by the presence of acids and salts.Inpresence of strong acids, little more than one-third can be precipi-tated; whilst in presence of a high concentration of neutral salts itis nearly all precipitated ; this limit is approached still more closelyif silver salts of weak acids are employed in place of silver nitrate.Colson’s work deals chiefly with the complexes in green chromicsulphate solutions, and the relations of those to the violet sulphate;he divides the green salts into three classes, according as one-third,two-, or three-thirds of the sulphate radicle is “masked,” that is,cannot be precipitated by means of barium chloride in cold solution,The completely masked variety can be obtained from the residue lefton spontaneous evaporation of a solution which has been exposed tosunlight during several months; it is also contained in the solutionobtained by reducing chromic acid by sulphurous acid at -4O.Some of ths compounds described by Weinland and Schumann arepartly chloride, partly sulphate, for example, the salt,CrClSO,,SH,O.With barium chloride, a solution of this salt yields all its SO, asbarium sulphate, but with silver nitrate it does not give an imme-diate precipitate.Other complex compounds are derivable fromthe chloride by union with ammonium chloride or sulphate.Thechlorides, chlorosulphates, and bromides also form the subject of thecontributions by Bjerrum.The papers by Pfeiffer and Werner deal with salts of variouscomplex “ aquo,” “ hydroxylo,” and ‘ I ammine ” chromic deriv&tives, and form part of the extended investigation of these complexesderived from various metallic elements.Derivatives of quinquevalent chromium have recently been ob-tained. The first of these were organic cornpounds,44 for example,the pyridine derivative obtained by acting on chromic acid withcold concentrated hydrochloric acid and adding pyridine. Now,however, purely inorganic derivatives have been prepared by R. F.Weinland and M. Fiederer 45; they are of the type MCl,CrOCI,,38 AbsIT., 1907, ii, 176, 177, 355.40 Jbid., 623, 877.42 Ibid., 966.44 Ibid., 1906, i, 37.3y Ibid., 167, 267, 356, 474, 780.dl Ibid., 694.45 Ibid., 1907, ii, 31.Ihid., 554, 622, 623.REP.-VOL.IV E66 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.where M is K, Rb, Cs, or (NH,), and they are crystalline and of adark red colour. They are prepared by dissolving chromic anhy-dride in hydrochloric acid at -ZOO, adding a solution of the appro-priate chloride, and again saturating with hydrogen chloride ; theyare decomposed by moisture. As proof of their exact nature, theisomorphism of the msium compound with the corresponding colum-bium derivative was directly determined, by the formation of homo-geneous mixed crystals of the two substances.Much of the recent literature dealing with chromic acid and itssalts need not be referred to, as it is concerned chiefly with thedescription of isolated salts and double salts.There has been con-siderable discussion as t o the state of matters existing in aqueoussolutions of dichromates ; on the whole, the fresh physico-chemicalevidence adduced by various observers tends in the direction of sup-porting Ostwald’s view that in solutions of chromic acid and ofdichromates the cations are principally Cr,O,”, and are not mostlysplit up into CrO,” and CrO,, as supposed by Abegg and Cox.From a full and careful study of solutions of potassium chromateswith excess of chromic acid or potassium hydroxide respectively, andof the solids in equilibrium with them, I. Koppel and R.Blumen-tha140 have shown that the four compounds, K2Cr04, K,Cr,O,,K2Cr3010, and K,Cr4013, exist throughout the whole range of tem-peratures from 0 to 60°, and that there is no evidence of the exist-ence of any other derivative within these limits of temperature.The most interesting points t o be noted with regard to uraniumare two papers dealing with uranous salts. For the preparation ofsome of these, especially the sulphate U(S0,)2,4H,0, J. Aloy andAuber4, recommend the reduction of uranyl salts by means ofsodium hyposulphite.A considerable amount of work has recently been done dealingwith complex salts containing molybdenum; R. F. Weinland andH. Kuhl48 describe a number of sulphate-molybdate salts, of whichthe simplest is represented by the empirical formula,K,O,SO3,2Mo0,,2H,O ;they are obtained by the action of excess of sulphuric acid onmolybdates, or by the action of concentrated solutions of sulphateson molybdenum oxysulphate; they all crystallise, and all are decom-posed by water, A large number of double or complex molybdates,derived from chromium, aluminium, or iron, on the one hand, andthe alkali metals, alkalineearth metals, &c., on the other, have beenprepared and described by R. D.Hall.49From the fact that inolybdic acid, when added t o solutions of47 Ibid., 557 ; compare also A. Colani, ibid,, 878,49 Ibid., 655.49 Abstr., 1907, ii, 356.48 Abstr., 1907, ii, 6251NORGAKIC CHEMISTRY. 67optically active hydroxy-acids, causes a very marked change in therotatory power, it has been concluded that complexes are formed bythe interaction of these substances ; additional evidence in supportof this view is provided by E.Rimbach and C. Neizert,6* who findthat on mixing isohydric solutions of molybdic acid and theseoptically active acids, there is a very marked increase of conductivitybeyond what would otherwise be expected ; this increase may amountto as much as 300 per cent.Ordinary ammonium molybdate, (NH4)10M012041, has been sub-jected to a physico-chemical investigation, according t o variousmethods, by J. Sand and F. EisenIohr,61 and from the results theydecide that in aqueous solution the composition of the anion isM O ~ ~ O , ~ , with a tenfold charge; further that, when the splution istreated with alkali, these ions yield the anion, Mo6OZ2, with aneightfold charge, as an intermediate stage before passing into thefinal one of MOO,", when sufficient alkali is added.Fluorine derivatives of sexavalent tungsten and molybdenum aredescribed by 0.Ruff, F. Eisner, and W. Heller.52 The molybdenumcompounds have the composition, MoF,, MoOF,, and MoO,F,, andthere are similar tungsten derivatives ; a n interesting point concern-ing the oxy-compounds, as well as the others, is the fact that theycan ba obtained by the action of anhydrous hydrogen fluoride, inexcess, on the corresponding chlorine derivative.Group VII.From a study of the freezing-point and boiling-point curves ob-tained for mixtures of the halogens, Karsten63 draws the follow-ing conclusions : I n agreement with the statements of Lebeau,5* thereis no evidence whatever that chlorine and bromine unite to form anycompound-gaseous, liquid, o r solid ; the '' compounds " described byother observers are solutions and mixed crystals of the two elements,and of the mixed crystals there is a continuous series. The compoundIC1 exists, not only in the liquid state, but also in the state ofvapour; a t the temperature of loo", it is very slightly dissociated.I n conclusion, it is pointed out that chlorine and bromine have lessmutual affinity than bromine and iodine.Similar conclusions aredrawn by Roo~eboom,~~ who also shows that; the compounds IBr andIC13 are very feeble, ICl being very stable in comparison,Investigations on the basicity of hydrofluoric acid are publishedby Kremann and Decolle,66 and by Pellini and Pegoraro 67; from con-6o Abstr., 1907, ii, 269.63 Ibbid., 447.m Ibid., 843. 65 Ibicl., 80.66 ]bid., 756,51 Ibid., 178, 179.67 ICid,, 860.62 Ibid., 268, 624.F 68 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ductivity determinations on various solutions of acid and salts, bothsets of observers conclude that hydrofluoria acid is dibasic, inharmony with the formula H2F2, deduced by other observers fromcryoscopic determinations on not too dilute solutions of the acid.Bourion 58 proposes a general method for preparing anhydrousbromides of the metals, which consists in heating an oxids of themetal to it suitable temperature (in no case above red-heat), andpassing over it a current of hydrogen bromide, into which sulphurchloride is volatilised; the bromides are thus obtained either in thefused state, or more o r less crystalline.In the case of the rareearths it was found that, no matter what oxalate be employed, thebromide formed is that corresponding with the formula MBr,.It is known that the presence of soluble chromate greatly increasesthe current-efficiency in the electrolytic preparation of hypochloritesand chlorates, but, owing to the colour, the use of such compoundsis inadmissible in preparing electrolytic “ bleach.” Betts andSherry 59 have therefore studied the effect produced by the additionof a number of other substances, but, although they have been partlysuccessful in improving the results, they have found no substance soserviceable as sodium chromate.They found, however, that the useof certain metals as caihodes heightened the eficiency, both inchlorate and in hypochlorite preparations ; a magnesium cathodegives results comparable with those obtained by adding chromate,but there is a considerable loss of magnesium-about 1 part forevery 50 of chlorate made. In preparing hypochlorite, it was foundthat, by using cells in series, with carbon electrodes in the first andmagnesium afterwards, the magnesium loss could be kept down to0.2 part per 100 of chlorine, obtaining a conversion of 35-50 percent. of salt, with a current efficiency of 60 per cent.The action of dry hydrogen chloride on manganous dioxide sus-pended in carbon tetrachloride has been investigated by W.B.Holmes.60 A solid material is obtained, which consists of manganesetetrachloride and trichloride; when this is treated with anhydrousether, the trichloride dissolves, forming an intensely violetrcolouredsolution, leaving a reddish-brown residue of tetrachloride. The tri-chloride itself is a black solid with a greenish tinge; treated withalcohol, it yields a wine-coloured solution, which apparently con-tains the tetrachloride; when its ethereal solution is shaken withmuch water, only half of the manganese is precipitabed. The tetra-chloride dissolves in absolute alcohol, and the solution slowly decom-poses and becomes colourless; in contact with ether it graduallyyields trichloride, which dissolves; when heated to looo, i t evolvesb8 Abstr., 1907, ii, 779.50 IbitE., 449.lbid.> 8T3INORGANIC CHEMISTRY. 69chlorine, and leaves manganous chloride ; when the alcoholic solu-tion is diluted with water, the whole of the manganese is pre-cipitated.Muir 61 has succeeded in obtaining permanganic acid in the formof very unstable, violet-black crystals, by evaporation of the solutionobtained by the interaction of barium permanganate and sulphuricacid. It was impossible to prepare trhe substance in a pure stateowing to decomposition, it being always mixed with brown or blackdecomposition products.Group VZIZ.A large number of papers deal with alloys containing members ofthis group, but few of these provide matters of general interest.The influence on the specific volume and the specific heat of iron,exerted by various additions of carbon and metals, has been veryfully studied by ITT.Brown.62 The specific volume is increased by anumber of elements besides carbon, although in some cases thisholds only for small additions, and the effect is reversed with in-creased amounts; in a number of cases, the specific volume dimin-ishes from the beginning. Other papers, dealing with special castirons and steels, and with other similar iron alloys of actual orpossibld technological importance, refer principally to materialsobtained by admixture of boron, tantalum, chromium, molybdenum,tungsten, and nickel, and to the influence which some of these exerton the nature and amount of the carbon retained by the iron.Theexact nature of the (‘ slag,” or non-metallic impurities containedin steel, is described by E. F. Law 63; as a rule, this material consistsof sulphides or silicates of iron or manganese, and oxide of iron.Manganous sulphide is formed preferentially t o ferrous sulphide,which therefore rarely occurs unless the proportion of manganese inthe steel is low; the presence of patches of sulphide is recognised bycoating the metal with a gelatin emulsion of a lead or cadmiumsalt. The silicates of the metals are very brittle, and their presencehas therefore an important bearing on the behaviour of tha materialduring rolling. Oxides, if present, are disseminated through themetal as minute specks, and have an important influence in increas-ing the corrosiveness of steel, due t o electrochemical action; theamount present can be determined by reduction in a current ofhydrogen, using special precautions.An interesting point connectedwith the occurrence of manganous sulphide in steel is also noted byA. A. Baikoff,6* who considers that substance to be a normal con-stituent of steels, although in small quantity; he points out that the61 Traiu., 1907, 91, 1485. 6a Abstr., 1907, ii, 958.&id., 692. Ibid, 87470 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.small but well-formed octahedral cryst'als, sometimes found in cavitiesin ingots, consist really of manganous sulphide, coated first withferrite and subsequently with pearlite; they are therefore '' epi-morphs," the shape being derived from the kernel of sulphide.I n connexion with the reinvestigation of the conditions of equi-librium in the system: Fe, FeO, C, CO, and CO,, R.Schenck andothersrG came to the conclusion that the cementation of iron ispossible only when the surrounding atmosphere contains 96-99 percent. of carbon monoxide, for only then does reduction of the gas,with formation of carbide, take place; in an experiment t o test thisresult experimentally, somewhat lower values were obtained.The action of various reagents on metalliu iron may be noted.C. F. Burgess and S. G. Engle66 find that in normal hydrochloric orsulphuric acid, the, rates of dissolution of electrolytic iron, temperedsteel, ordinary cast-iron, and soft sheet-iron, are approximately inthe ratio 40, 10, 7, and 1, but that a preliminary heating of theelectrolytic iron t o about l,OOOo, followed by slow cooling, reduces itt o the same rate as the soft iron.Traces of arsenic in the iron greatlyincrease the resistance to the action of acids. S. Birnie67 showsthat water itself acts on finely-divided iron a t all temperatura be-tween Oo and looo, hydrogen being evolved, and that the presenceof oxide in the iron greatly accelerates the action. Even iron filingsin presence of water alone bring about the reduction of nitro-benzene to aniline, according to A. Bruno,68 who also shows that aquantity of carbon dioxide, shaken for some time with iron filingsand water, becomes completely replaced by an atmosphere of hydro-gen, with formation of ferrous carbonate.The discussion regardingthe rusting of iron and steel has been reopened by W. R. Dunstan,"gand by W. H. Walker and collaborators.70 These all refute theassertion that the rusting is due to the presence of carbonic acid.The presence of alkali, however, has an inhibitory action, and theresults which seemed to indicate the absence of rusting in absence ofcarbonic acid were probably due to alkali dissolved from ordinaryglass vessels ; in Jena glass flasks, without carbonic acid, rustingtakes place almost as readily as in free air. Walker accepts theview that the action is really an electrochemical one, and describesthe experiment of treating iron with water containing traces ofphenolphthalh and potassium ferricyanide ; the metal soon exhibitszones of different polarity, becoming red where it is acting as cathode(with evolution of hydrogen), and blue where i t is acting as anode(with dissolution of iron).The dissolution stops when enough65 Abstr., 1907, ii, 470.67 Ibid., 469.6y Proc., 1907, 23, 63.66 Ibid., 29.68 Ibid., 756.70 Abstr., 1907, ii, 875INORGANIC CHEMISTRY. 71hydrogen for polarisation is produced, unless a depolariser (freeoxygen, hydroxylamine) is present.In continuation of the work on the volatility of various metals,referred to in last year's Report, Moissan determined the relativevolatilities of nickel and cobalt, a matter of some interest in viewof the closeness of their melting points.From the results obtainedby heating in an electric furnace with a current of 500 amperes a t110 volts, it appears that nickel is decidedly more volatile thancobalt, 56 grams of the former being driven off in the same time as19 of the latter. By means of an internally-cooled copper tube themetallic vapours can be condensed in the form of microscopiccrystals.The question as to whether the black precipitate, obtained whensolution of sulphide is added to solution of ferric salt, is ferric sul-phide or a mixture of ferrous sulphide and sulphur, is answeredby H. N. Stokes 71 in favour of the first alternative; and the evidenceseems fairly conclusive. By continued boiling with water, the pro.cipitate is converted into ferric hydroxide with evolution of hydro-gen sulphide; ammoniacal zinc chloride, which does not act onferrous sulphide a t the ordinary temperature, does so in sealed tubesat 170", forming ferrous hydroxide and zinc sulphide; with alkalinezinc solution the black sulphide from ferric salt gives a mixture offerric hydroxide and zinc sulphide.The black precipitate obtainedfrom ferrous salt and alkaline polysulphide also behaves as ferricsulphide.The complex iron derivatives known as Roussin's salts form thesubject of several papers by I. Bellucci and C. Cecchetti72 and byL. Cambi.73 According to the former, they are derivatives of a mono-basic acid, HFe4(N07)S3, the anion of which is quite well defined;these authors have described a number of new salts, many of whichare exceptionally stable.Most of the salts, when heated with alkali,decompose with formation of derivatives of the simpler acid,HFe(NO),S, but the tetra-alkyl salts can be boiled with a 50 percent. solution of potassium hydroxide without undergoing decom-position. The various new compounds, as a rule, form black crystalsor crystalline powders, and are stable in absence of light.The only matters of general interest in connexion with the com-pounds of nickel and cobalt deal with derivatives of higher oxides.I. Bellucci and S. Rubegni74 have prepared a definite compound ofsodium oxide with a higher oxide of nickel, and t o it they give theformula Na,0,Ni0,2Ni02. Bellucci and F. Dominici 75 have pre-pared potassium cobalto-cobaltite in a crystalline condition by'l Abslr., 1907, ii, 471.T4 IbirE., 94.72 Ibid., 29, 472, 960.i5 Ibid., 354.n Ibid., 9607 2 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.fusing, for three hours, potassium hydroxide with any oxide ofcobalt; they show its composition t o be K,0,Co0,3Co02.Anumber of complex molybdates have been obtained by C. Fried-heim and F. Keller,76 mostly by oxidation of cobaltous compoundsin presence of molybdates by means of ammonium persulphate orof hydrogen peroxide; some can be obtained from permolybdates.One of the ammonium compounds,3(NH,),O,CoO,CoO,,l 2 Mo03,20H,0,may serve as an example of the kind' of substance produced. Theviolet-red solution obtained when very concentrated solutions ofsodium tartrate, sodium hydroxide, and cobaltous sulphate aremixed, undergoes spontaneous oxidation on exposure to air, andbecomes green. I n presence of glycerol, the amount of oxygenabsorbed corresponds with one molecule for two atoms of cobalt, butthe resulting compound corresponds only with the oxidation-stage,Co203, which requires only one molecule for four atoms of cobalt.It is therefore assumed that the cobalt is first directly raised to theCOO, stage, but this then oxidises tartrate as a secondary reaction,and itself bezomes reduced to the Co,O, stage. The cobaltous solu-tion rapidly absorbs nitric oxide.A. Werner has again published several contributions to the chem-istry of the complex cobalti-derivatives.77Amongst the platinum metals there is very little of a purelychemical nature to record. A peculiar property of platinum amal-gam has been noted by Moissan,7* and confirmad by P. Lebeau7Q;when an amalgam containing even less than 0.1 per cent. of plat-inum is shaken with water, or when mercury is shaken with a dilutesolution of platinic chloride, a buttery mass is obtained which occu-pies about five times the volume of the original amalgam; this isunaffected, in general character, by change of temperature eitherdown as low as - 8 O O or up to looo. By cooling below the freezingpoint of mercury and then cutting sections of the solid mass, it isfound from microscopical examination that the structure consists ofsmall drops of water embedded in the amalgam, corresponding withan ordinary emulsion or lather; the action would therefore appearto be purely physical, and due to surface tension. Many otherliquids, and also solutions, form similar emulsions with the amalgam.The preparation of the platinum metals in the colloidal state, andtheir properties as catalysts, have been further studied by C. Paaland others.*O Colloidal osmium products were obtained by reducingalkali osmate mixed with sodium protalbate by means of hydrazine71s Abslr., 1907, ii, 96.78 Ibid., 360. 79 Ibid., 479. 8o Ibid., 360, 550.77 Ibid., 961, 962, 963, 964, 965I N 0 RG A N 1 C C H EM I ST 111’. 73hydrate or of aluminium ; this yields colloidal osmic oxide, which,after dialysis, can, with care, be evaporated to dryness. The product,on reduction by hydrogen a t 3 0 4 0 ° , yields colloidal osmium, solublein water and stable towards many agents, but oxidisable in air withformation of tetroxide. The authors find t,hat, as regards the cata-lysis of hydrogen peroxide, osmium hydrosol is the most active ofthose prepared by their method, next in order being palladium,platinum, and iridium ; for reduction experiments, colloidal palla-dium is much preferable to platinum.A matter of some practical importance in connexion with electro-lytic work is noted by C. MarieF1 who shows that platinum anodesbecome slightly oxidised during the electrolysis of solutions of plati-num chloride, hydrochloric acid, nitric acid, or sodium hydroxide.The oxide formed does not dissolve in the acids mentioned, but doesso if some iodide is also added.Most of the work concerning compounds of the members of thisgroup deals with complex derivatives. The salts of dihydroxylo-tetramvineplntinum, [(OH),Pt(NH,),]*-, have been investigatedby A. Werner,*Z and are discussed by him from the point of view ofhis theories of such compounds; he concludes that the differencesobserved by Carlgren and Cleve in salts prepared by differentmethods are due to the occurrence of stable polymorphous modifica-tions, and are n o t t o be referred to stereoisomerism. Unstable com-pounds derived from palladous chloride and hydroxylamine aredescribed by S. Zeisel and A. Nowak83; their composition isPd(NH30),C1, and Pd(NH30),Cl,, respectively, and the free basecorresponding with the latter can be isolated. The constitution ofthese compounds is also discussed in the light of Werner’s theory.HUGH MARSHALL.rlbstr., 1907, ii, 698. a2 Ibid., 969. 83 l b i d . ) 276

ISSN:0365-6217    

DOI:10.1039/AR9070400034

出版商:RSC    

年代:1907

数据来源: RSC

摘要:

ORGANIC CHEMISTRY-ALIPHATIC DIVISION.Contuct Actions at Elevated Temperutures.A. LARGE number of investigations have been carried out which dealwith the decomposition or interaction of gaseous substances at elevatedtemperatures under the influence of catalysts. The results are gener-ally of a highly descriptive and detailed character, and could not withadvantage be abstracted in a form suitable for the present Report.A few examples may, however, be cited in illustration of the generalnature of the work.Kusnetzoff 1 finds that finely-divided aluminium a t its melting point,like magnesium, brings about the complete decomposition of methane,ethane, and ethylene into carbon and hydrogen. A part of the carbonis deposited on the surface of the metal, and the remainder combineswith the metal as carbide.Mayer and Altmayer 2 have made a further study of the eqiiilibriumbetween carbon, hydrogen, and methane at high temperatures inpresence of metallic nickel or cobalt.The reaction was studied fromboth directions, starting, that is, either from methane or from itselements. The methane was prepared from aluminium carbide byaction of water, and the carbon employed was that resulting from thedecomposition of methane by heat. From their results, they calculatethat, at the pressure of one atmosphere, the proportion of methanepresent, at 250' is 98.78 per cent., at 536O it is 51.16 per cent., and at850°, 1.21 per cent, It is considered improbable that methane couldhave been synthesised from its elements at 1200' as stated by Boneand Jerdan,s and i t is suggested that the result obtained by theseauthors must have been due to impurity in the carbon employed.von Wartenberg,* in agreement with Wallis,5 finds that cyanogen isnot produced at 3500O from carbon and hydrogen, although, accordingto Nernst's theory, the equilibrium mixture at that temperatureshould contain 44 per cent.of cyanogen. The same author has alsomade experiments on the synthetic formation of acetylene. A prelim-Abs.fr., 1907, i, 669.Trans., 1897, 71, 41.Jbid., 1906, i, 730.= Ibid., 457.Abstr., 1907, i, 299ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 75inary experiment gave 0.13 per cent. of acetylene at 1824O, which ismuch lower than the calculated va1ue.GIpatieff has studied the reduction of various substances by hydrogenat high temperatures in presence of catalysts, and shows that hydrogenand acetone react, in presence of iron or nickel, t o give isopropylalcohol, and that the reaction is limited and reversible. It is statedalso by the same author 8 that oxides of nickel may bring about thecatalytic reduction of various compounds more quickly than reducednickel.Sabatier and Mailhe9 have also studied the reduction of ketones inpresence of nickel.They find that diacetyl yields dimethylketol andpy-butanediol; acetylacetone breaks down, giving a mixture of variouscompounds, but acetonylacetone is almost quantitatively convertedinto Pc-hexylene oxide. The Rame authors state that carbimides mayalso be reduced in a similar manner. Ethyl carbimide yields methyl-ethylamine, but mono-, di-, and tri-ethylamine are also produced.Phenyl-carbimide gives aniline and methane ; phenylcarbamide is also formedpresumably by the action of water on the original substance. iso-Cyanides, which cannot be directly reduced in the wet way owing totheir rapid decomposition by water, may easily be reduced by thecatalytic method above mentioned. .These authors 10 also find that, when the vapours of acetic anhydrideare mixed with hydrogen and passed over nickel at 180°, the productsare acetaldehyde, ethyl acetate, ethyl alcohol, and acetic acid. Theyconsider that acetaldehyde and acetic acid are first produced, and thatthe former then undergoes further reduction to ethyl alcohol.Sabatier l1 finds tbat ally1 alcohol is in a similar way easily reducedt o propyl alcohol.Senderens 12 states that when the vapours of ethyl alcohol are passedover animal charcoal at 350°, a mixture is produced of methane,ethylene, hydrogen, carbon monoxide, and a little carbon dioxide.Propyl alcohol yields principally propylene, with some ethane, carbonmonoxide, and hydrogen.Lemoine,l3 using wood charcoal at 350°, obtained, from ethyl alcohol,acetaldehyde and hydrogen.Senderens 14 also finds that alcohols may be dehydrated to olefineswhen they are heated with amorphous phosphorus.Ethyl alcohol,for example, at 215-240° gave a mixture containing 95 per cent.of ethylene and 5 per cent. of hydrogen phosphide.Compare Pring and Hntton, Tram., 1906, 89, 1591.* Ibid., 828.Ibid., 488, 587.lo Ibid., 747.Ibid., 458. 1p .Ibid., ii, 248.l3 Ibid., 248. l4 Ibid., i, 577.7 Abstr., 1907, i, 82776 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.IIydroccwbons.The isomeric octanes, which have been already described, are as follows :(1) n-octane ; (2) diisobutyl ; (3) y-methylheptane, and (4) hexa-methylethane (Henry, 1906). L. Clarke,15 in the course of a studyof these hydrocarbons, has now succeeded in synthetically preparingan additional isomeride, namely, 8-methylheptane. By condensingP-iodopentane with ethyl sodioacetoacetate and hydrolysing theproduct, the ketone, CH,*[CH,],*CHMe*CH,*CO-CH,, is obtained ;this is reduced t o the corresponding secondary alcohol, which bytreatment with iodine and phosphorus yields the hydrocarbonspecified.The physical properties of liquid and solid acetylene have beeninvestigated by McIntosh.lG The density of the liquid a t - 79" is0.61, and at - 64.8" it is 0,577.At atmospheric pressure, the densitywould be 0.618 supposing that the substance were still a liquid.This gives a molecular volume of 42.1, whereas the value calculatedfrom Kopp's numbers mould be 33. The atomic volume of carbon inliquid carbon monoxide17 is 22 or 23, and, if it is supposed that one ofthe carbon atoms in liquid acetylene has this value, the observedvolume of the compound will, agree fairly well with the calculatednumber, This result therefore appears to favour the acetylideneformula C:CH, of Nef.lsRlolinari 19 considers that by the behaviour of ozone it is possible todistinguish between double and triple linkings, since the latter,according t o his observations, do not absorb ozone.By the samemethod, he proposes to distinguish between benzenoid compoundswhich contain a true double linking and those which should berepresented by the " centric " constitution. Qualitatively, the test iscarried out by simply passing ozonised air through a solution of thesubstance to be investigated in some inert solvent, and testing theissuing gas for ozone by means of potassium iodide. I n some cases, asin unsaturated fatty acids, the test may be applied in a quantitativemanner by comparing the (' iodine number " and the '' ozone number "in the resulting compound ; if the two agree, only double linkings arepresent, but if the former is greater, triple linkings are also indicated.By these methods, the author found that stearolic acid,CH,*[CH,],*CiC[CH2]7*C02H,and phenylpropiolic acid, C6H,-CiC*C0,H, did not combine with ozone.I n the latter acid, therefore, the centric constitution is given to theC,H, group.l5 Abstr., 1907, i, 169.16 Ibid., 458.Compare Baly and Donnan, Tram., 1902, 81, 907.Ann. Report, 1906, 78. l9 Abstr., 1907, i, 1039ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 77Harries,20 however, considers that these results and conclusions areinexact or untrue. His experiments show that certain compoundswith triple linkings combine with ozone more rapidly than those withdouble linkings.He shows further that, contrary to Molinari'sstatement, both stearolic and phenylpropiolic acids combine with ozonet o give ozonides. The disruption of the triple linking by theaction of ozone and decomposition of the resulting ozonide may berepresented as :*CIC* + 0, = *C=C* + H20 = -CO*OH + HO*OC-\/stearolic acid, for example, giving azelaic and pelargonic acids.It has been shown by Sir W. H. Perkin that the magnetic rotatorypower of hexylene, diallyl, and dipropargyl gave about the normalvalues, only a slight increase being observed in the value for eachunsaturated grouping as the number of such groupings increased.The two acetylene groiipings in dipropargyl appeared to behavelike four ordinary unsaturated groups ; in comparing dipropargyl withits isomeride, benzene, however, it is found that the latter has amuch higher value.A t first it appeared probable that the higherrotation of benzene was in some way connected with ringformation,but the abnormally high value which was found for A3 :*(')-p-mentha-diene 21 suggested the possibility that the increase was principally duet o the presence of unsaturated groups in conjunction.I n order to test this supposition, the same author22 considered itdesirable to examine some open chain compounds containing unsatur-ated groups in conjunction, and in the first instance selected for thispurpose the simple hexatriene, CH,:CH*CH:CH*CH:CH,, of vanRomburgh and Dorssen.23This hydrocarbon was found to have a remarkably high rotation,the value being 12,196.The difference in the formula of hexatrieneand benzene is due to ring-formation with loss of two hydrogen atoms,and in the similar case of hexane and hexamethylene the value oE thisdifference was previously found to be 0.982.24 The value thereforefor benzene, obtained by subtraction, is 11.214, which correspondsalmost exactly with the experimental value 11.284. This resultappears to be in favour of KekulB's formula for benzene, and italso indicates that the contiguous unsaturated groupings in benzenehave the same value as in the open chain compounds.Miss Smedley 25 has measured the molecular refractions of diphenyl-2o Abstr., 1908, i, 75.22 l'rwis., 1907, 91, 806.24 Tram., 1902, 81, 295.21 Compare Briihl, Proc., 1906, 22, 319.Zy Abstr., 1906, i, 130.26 Proc., 1907, 23, 29578 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.butadiene and diphenylhexatriene, and from the data obtained hascalculated the influence of the phenyl and ethenoid groups inunsaturated hydrocarbons.In each case, the refractive power ofthe group increases markedly as the number of unsaturated groupswith which it is conjugated increases. The influence of the hexa-triene structure is always greater than that of the benzene ring,and it is considered by the author that this result is at variancewith the representation of the benzene molecule as a closely con-jugated system of double bonds.Diphenylhexatriene has been prepared by the same author by thecondensation of phenylisocro tonic acid with cinnamaldehyde in pre-sence of acetic anhydride, Its solution in benzene exhibits aremarkable blue fluorescence.2”Aldehydes and Ketones.Notwithstanding the large amount of work which has been done onthe polymeric modifications of formaldehyde, there is yet much un-certainty and often confusion in designating the individual substances.Auerbach and Barschall 27 have continued their interesting studies onthis subject,28 and the following solid polymerides are classified anddescribed.Paraformaldehyde is prepared by concentrating a solution of form-aldehyde ; it is amorphous, colloidal, and contains variable amounts ofadsorbed water.Its molecular weight is yet unknown, but is not lessthan (CH20),. It crystallises in needles or prisms, and melts at 6 3 O(closed tube), Its solution gives none of the ordinary aldehydicreactions, and the compound probably has a cyclic constitution.a-, /3-, y-, and 6-Polyoxymethylenes are all more or less crystallineand of unknown molecular weight.The first three are obtained bythe action of concentrated sulphuric acid, under different conditions,on solutions of formaldehyde ; 8-polyoxymethylene is prepared byprolonged heating of the 7-variety with water. The four polyoxy-methylenes and paraforrnaldehyde all tend to pass gradually intosimple formaldehyde when dissolved or vaporised.Orloff 29 considers that in the ordinary method of preparing form-aldehyde from methyl alcohol the initial change consists in thedecomposition of the alcohol into formaldehyde and hydrogen, and thatthe formaldehyde itself suffers some decomposition into carbonmonoxide and hydrogen.The same author has made a large numberof experiments on the influence of various catalysts on the oxidationof methyl alcohol.26 Proc., 1907, 23, 163.3* Ann. Repoyt, 1905, $3.9 Chern. Zentr., 1907, ii, 1734.2g Abstr., 1907, i, 892, 1008ORGANIC CHEMTSTRY-ALIPHATIC DIVISION. 79The present writer 30 finds that carbon dioxide in aqueous solutioncan be reduced by means of metallic magnesium to formaldehyde.The change is much facilitated by the presence of substances whichreact with formaldehyde, such as ammonia or phenylhydrazine. Formicacid may, in ,a simiIar way, be reduced to formaldehyde, and thereaction may be utilised as a characteristic test for formic acid.31It was shown by Blank and Finkenbeiner, and by Harden, thatformaldehyde reacts with hydrogen dioxide in a1 kaline solution,‘givingfree hydrogen and a metallic formate.Geisow afterwards stated that,if the action takes place in neutral or acid solution, no formic acid isobtained, but only carbon dioxide and hydrogen. The latter statementis now contradicted by Lyford,32 who finds that formic acid is producedas an intermediate stage and on further action is oxidised to carbondioxide. The <author also states, contrary to Geisow’s observation,that barium formate is produced when formaldehyde reacts withbarium dioxide.By the condensation of formaldehyde and acetaldehyde in presenceof calcium hydroxide, Tollens and Wigand, in 1892, obtained penta-erythritol, C(CH,*OH),.This change was considered by Nef to takeplace in stages, hydracrylaldehyde, HO*CH,*CH,*CHO, PP’-dihydroxy-isobutaldehyde, (HO*CH,),CH*CHO, and pentaerythrose,C(CH,* OH),*CHO,being intermediate compounds. A. F. RlcLeod 33 has recently endea-voured to obtain experimental proof in favour of this hypothesis, andhe has succeeded in showing that, under the influence of very dilutesodium hydroxide solution, a mixture of acetaldehyde and formaldehydeyields considerable amounts of pentaerythrose. The latter compound,it is true, could not be isolated as such, but mas converted by reductioninto pentaerythritol. The presence of /3/3’-dihydroxyisobutaldehydewas also identi6ed.It is further shown by the author that hydracryl-aldehyde and formaldehyde undergo condensation i n presence ofsodium hydroxide, giving pentaerythrose in almost quantitative yield.By the interaction of formaldehyde and hydrazine hydrate,Pulvermacher, in 1893, obtained a white, amorphous compound havingthe formula (C,H,N,),, which he named ‘‘ formalazine.” It is veryinsoluble in water, alcohol, or ether, and by the action of acids isreadily hydrolysed to the parent substances. Stoll&3s has now madea further study of the reaction in the hope that, under different con-ditions, it might be possible t o obtain triaminotrimethylenetriamine ;the latter compound has so far only been isolated in the form of ay1 Fenton and Sisson, Proc.Cainb. Phil. SOC., 1908, 14, [iv], 376.32 Abdr., 1907, i, 823. 33 Ibid,, 172.85 Abstr., 1907, i, 496.Trans., 1907, 91, 687.Ann. &port, 1904, 6380 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.con densation product with ~alicylaldehyde.~~ By adding bydrazinehydrate (1 mol.) drop by drop to 40 per cent. formaldehyde solution($ mol.) and evaporating on a water-bath, an amorphous product wasobtained which is completely soluble in water and which has theempirical composition CH4N2. The same product can be obtained byheating trioxymethylene with hydrazine hydrate to 100' in a sealedtube. The author considers that it is apolymerised form of methylene-hydrazine, (CH,:N*NH,),, the silver derivative having the composition(H,C: N,H,),,ZAgNO,.Triaminotrimethylenetriamine does not appeart o be formed in the reaction.Many different opinions have from time to time been expressed withregard to the formula of metacetaldehyde. Determinations of themolecular weight by means of the vapour density or cryoscopic methodshave been made by Friedel, Hanriot and Oeconomides, Troeger, Orn-dorff and White, and the results pointed to the termolecular formula,The last-named authors considered that paracetaldehyde and met-acetaldehyde are to be represented by the same plane formula, andthat the difference in their properties is t o be explained by stereo-isomerism. To paracetaldehyde, this being the more stable modifica-tion, the trcms-configuration was assigned. By keeping metacetaldehydefor a considerable time, they obtained a brittle and opaque modifica-tion which was more soluble in phenol or thymol, and the molecularweight of which corresponded to that of tetra-aldehyde.Zecchini, however, obtained numbers for metacetaldehyde which bythe boiling-point method in chloroform agreed with the sexamolecularformula, and by the cryoscopic method, using phenol as solvent, thequadrimolecular formula was approximately indicated.Hantzsch and Oechslin 37 have made further determinations of themolecular weight in phenol and in thymol solutions by the cryoscopicmethod, and they conclude that metacetaldehyde exists only i n a singleform, and is quite stable when pure.Their numbers indicate thequadrimolecular formula when phenol is employed as solvent, and arethe same whether the substance is freshly preparedor not.I n thymolsolution, the compound appears to be sexamolecular. Metacetaldehydetherefore is not isomeric with paraldehyde, but is a higher polymeride.Raper 38 has studied the condensation of aldol under the influenceof a dilute solution of potassium carbonate. The result is shown to bea, hydroxyoctaldehyde with a straight chain, since, on oxidation t o thecorresponding acid and reduction with hydriodic acid, it yields n-octoicacid. According to Lieben's rule,39 it would be expected that the firstcondensation product should be an aldehyde with a branched chain,31; Di&n aiid SchdF, 1895.38 Trans., 1907, 91, 1831.37 ribsty., 1907, i, 1009.Abslr., 1901, i, 449ORGANIC CHEMISTRY-ALIPHATIC DIVISION.81which by oxidation and reduction as above would yield a-ethylhexoicacid.Kling and Roy40 show that when metallic magnesium acts onaliphatic aldehydes in benzene solution, nldol condensation takes placeand the resulting aldols are then reduced to glycols. It is supposedthat the aldehyde, for example, acetaldehyde, reacts in the two des-motropic forms CH,*CHO and CH,:CH*OH, yielding the intermediatecompound, CHMe<(g:>CH*OH, which is transformed by waterinto the glycol, OH*CHMe*CH,*OH, I n support of this hypothesis,it is stated that aldehydes, such as chloral, i n which similar tauto-merism is not possible, do not give a similar reaction.Glyoxal was discovered by Debus in 1856, and was described by himas a colourless, amorphous, and somewhat brittle mass.Bottinger, in1878, obtained it by Lubavin’s method in the form of a yellow syrup,and it appears in this form when prepared from mesoxalic semi-aldehyde.41 Although a large number of investigators have beenconcerned with the reactions and transformations of this substance, itsindividual properties appear to have been scarcely studied. It nowappears from the researches of Harries and Temme4, that the trueunimolecular glyoxal has not hitherto been obtained. Debus’s productis considered by these authors to be a polymeride, or a mixture ofpolymerides, of unknown molecular weight, for which the name poly-glyoxal is suggested. They have succeeded, however, in isolatingthe true unimolecular compound by heating the commercial productwith phosphoric oxide.A green gas i s obtained, which can be con-densed in a well-cooled receiver in the form of beautiful yellowcrystals. These melt at 1 5 O to a yellow liquid, which boils at 50°,producing an emerald-green vapour. The vapour can be condensedagain to a green liquid, which becomes yellow on cooling, and at 16’solidifies to yellow prisms which, however, become white on strongcooling. The vapour burns with a violet flame, and forms a stronglyexplosive mixture with air. Analysis and vapour density deter-mination by Victor Meyer’s method indicate the simple formulaC,H,O,. Unimolecular glyoxal can only be kept for a few hours, sinceit readily undergoes polymerisation, even when placed in a freezingmixture, giving an insoluble modification, (CHO),, which the authorsdesignate as paraglyoxal.This change occurs immediately in thepresence of a small amount of water ; if, however, the simple glyoxalis poured into a large quantity of water, it dissolves completely. Thesolution so obtained contains the compound still in the unimolecularAbstr., 1907, i, 586.42 Abdr., 1907, i, 183.REP.-VOL. IV,-I1 Tmns., 1905, 87, 814.82 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,condition, as is evidenced by cryoscopic determination, and by the factthat with phenylhydrazine it yields the well-known glyoxaldi-hydrazone, melting a t 167-1 68’. The solution is colourless, has afeebly acid reaction, and strongly reduces ammoniacal silver solutions ;it does not, however, reduce Fehliag’s solution.The molecular refraction of glyoxal was found to be 18.86, tlhecalculated value for CHO-OH0 being 11 ~678.An oxymethylenecompound of the formula OC:CH(OH) would require the value 12,619.Briihl points out 43 that, whilst optical exaltation is always observedin the combination C:C*C:O, the group O:C*C:O yields the normalvalues for the molecular refraction and dispemian. The latter fact isshown to be the case, for instance, in diacetyl, acetylpropionyl, pyruvicacid, and ethyl oxalate ; as regards molecular refraction, glyoxal is afurther example,The yellow or green colour of glyoxal is of interest in connexionwith the similarity of colour in other compounds containingcarbonyl groups in co~junction.~~ Further, it would appear thatglyoxal is the simplest coloured compound known which contains onlycarbon, hydrogen, and oxygen.When freshly-distilled cinnamaldehyde is dissolved in chloroformand subjected to the action of ozone, an unstable ozonide is obtained,which, when acted on by water, decomposes in the following manner :C,H,*CH-CH*CHO\/ -+ C,H,*CHO + CHO*CHO.0,The resulting solution (after removal of benzaldehyde and benzoicacid by extraction with ether), when evaporated in a vacuum at25-30’, leaves a yellow mass, which, after drying at 100’ overphosphoric oxide, is obtained in the form of an amorphous, friable,yellow substance which dissolves easily in water.Cryoscopic deter-mination shows that in solution this modification is termolecular, butno corresponding derivative can be obtained from it, since in solu-tion it passes quickly into the unimolecular form ; phenylhydrazine,hydroxylamine, and sodium bisulphite, for example, yield only deriv-atives of the latter form.Although in its general properties this ter-molecular form resembles Debus’s product, it differs notably from thelatter and from the unimolecular form in that it reduces Fehling’ssolution. I n order to explain this difference, the authors suggest thatthe termolecular form has been produced by aldol condensation, andhas the constitution CHO*CH(OH)*CO*CH(OH)*CO*CHO. The43 Trans,, 1907, 91, 115‘4 Compare, for example, ethyl dioxosuccjnate (Anschiitz and Parlato, Abstr.,1892, 1181) ; ethyl oxomalonate (Curtiss, ibid., 1906, i, 480), diacetyl, &cORGANIC CHEMISTRY-ALPHATIC DIVISION.83cupric reducing power would then be attributed to the CH(0H) group,and the compound would appear to be related to the sugars.Four modifications of glyoxal are therefore known, namely, the uni-molecular and termolecular forms, insoluble paraglyoxal, and Debus’spol y gl J oxal .It has been previously mentioned that methylglyoxai wasisolated by Harries and Turk, but was only obtained in the poly-meric form (C,H40,),.45 I t appeared probable, however, that byheating this product with phosphoric oxide it might behave likepolyglyoxal, and in this way the unimolecular methylglyoxal could beisolated. The present authors find, on making this experiment, thata yellow oil is obtained which emits a green vapour, and that theboiling point of the liquid is higher than that of glyoxal; the yield,however, is only small.Bacon and Freer 46 have made a further study of the action ofsodium on acetone, and they consider that the results confirm theirearlier statements.47 The initial substance is said to be sodiumacetone, C,H,NaO; i t is white, but turns red in the air.Whentreated with dilute hydrochloric acid, i t regenerates acetone, and withice-cold acetic acid the products are acetone with small quantitiesof ethyl and isopropyl alcohols and pinacone.Ciamician and Silber have previously shown (1 903) that acetone inaqueous solution is decomposed under the influence of sunlight, givingmethane and acetic acid.They have now 48 studied the behaviour ofsome other ketones under similar circumstances, and find that methylethyl ketone behaves in the same way, yielding ethane and acetic acid.L;evulic acid gives propionic acid with, probably, formic acid andmethyl alcohol.Dimethylketol or acetylmethylcarbinol, CH,*CH(OH)*CO*CH,,which was discovered by von Pechmann in 1888, is best obtained bythe reduction of diacetyl. The most suitable conditions for effectingthis reduction and of preparing diacetyl have recently been describedby Diels and step ha^.^^ They succeeded in obtaining 1300 grams ofpure diacetyl from 4 kilograms of methyl ethyl ketone, and theyield of dimethylketol is 45 per cent. of that required by theory.von Pechmann and Dahl obtained two solid modifications of dimethyl-ketol melting respectively a t 1 2 6 O and 94-9S0, but the molecularweights could not be determined, since the substances appeared toundergo de-polymerisation when dissolved, Diels and Stephan nowgive the melting points as 126’ and 8 5 ~ 5 ~ ; they find that both modifi-46 Ann.Xeport, 1905, 74.47 Compare Miss Taylor, Ann. Report, 1906, 81.46 Abstr., 1907, i, 479.Abstr., 1907, i, 587. 49 lbid., 1000.a 84 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.cations can easily be recrystallised ; molecular weight determination inboiling acetone indicates that both forms are bimolecular. I f , however,these polymeric forms are treated with ether, they lose their power ofcrystallisation, and tend to pass back to the unimolecular liquid modi-fication.This fact probably explains the somewhat different results ofthe earlier investigations, since ether mas then employed for removingthe unchanged dimethylketol.Biltz5O shows that by heating dimethylketol with carbamide inCH,*#*NHanhydrous acetic acid, dimethylglyoxalone, CII,.C.NH>CO' is Ob-tained. The properties of this product differ considerably from thoseof the dimethylglyoxalone which Kunne obtained in 1898 from amino-methyl ethyl ketone and cyanic acid. In this compound, the hydrogenatoms in both the irnino-groups may be acetylated by means ofacetic anhydride in presence of sodium acetate, This appears tobe a general rule, the only exceptional case so far recorded beingRupe's monophenylglyoxalone, in which he succeeded in replacing onlyone o€ the imino-hydrogen atoms by acetyl.I€ an imino-group issituated between two carbonyl groups, the basic character of theimino-hydrogen atom is so much diminished that either acetylation isno longer possible, or only very unstable acetyl derivatives are pro-duced. The author cites, amongst other examples, that of parabanicacid, which yields no acetate, and hydantoin, which gives a diacetateeasily hydrolgsed by water.Dimethylketol also condenses with ethyl oxalate, forming a compound,C,H,O,, which is probably a hexamethylene derivative,It has acid properties, and yields a dihydrazone with phenylhydrazineand a quinoxaline derivative with ~-phenylenediamine.~lLapworth,52 in the course of an investigation on the formation anddecomposition of oximes in presence of acids, shows that formaldehyde,in presence of concentrated hydroehloric acid, is a most effective agentin removing the hydroximino-groups of ketoximes. The author con-siders that, in presence of acid, the oximes react as hydroxyhydroxyl-amine compounds, and that the additive compound formed with form-aldehyde then undergoes a transformation analogous t o Beckmann'schange, yielding formic acid, ammonia, and the ketone :>C<NH*OH N(OH)*CH,*OH --f>C<EH*OH -+ >C<OH NH'CHo -+> CO + NH,+H*CO,H.OH f CH,o >'<OH6o AEstr., 1908, i, 56.52 Trans., 1907, 91, 1133.51 Diels and Stern, ibid., 1907, i, 466ORGANIC CHEMISTRY-ALIPHATIC DIVISION.85Attention is drawn to the readiness with which oxime formation maytake place, in many cases, in presence of concentrated hydrochloricacid, a fact which does not generally appear to be sufficiently recog-nised.Further, it is shown that when hydroxylamine and formaldehydereact in presence of excess of concentrated hydrochloric acid, a notablequantity of methylamine is produced, the hydroxylamine being there-fore reduced by formaldehyde.The same author and Barrett 53 have studied the influence of acidsand alkalis on the velocity of formation of acetoxime. They showthat in a solution containing one gram-molecule each of hydroxylamineand acetone in 40 litres at 0", the velocity of oxime-formation is leastwhen no other base or acid is present.Sodium hydroxide causes a verylarge acceleration, which is nearly proportional to the concentration.Hydrochloric acid also causes considerable acceleration, the increasebeing rapid until half a gram-molecule of the acid has been added.Beyond t h i s proportion, the rate diminishes, and attains a nearlyconstantvalue when rather more than one molecule of the acid is present.The properties of dimethylketen, (CH,),C:CO, have been furtherstudied by Staudinger and K l e ~ e r . ~ ~ During the preparation of thissubstance by the method previously described,55 polymerisation pro-ducts are obtained, one of which, a solid, appears to be identical withthe diketone of Wedekind and Weisswange 56 which was obtained bythe action of triethylamine on isobutyryl chloride.It is now foundthat a liquid polyrneride is also produced which has the bimolecularformula (C,H,0)2, and which differs from the condensation productfirst mentioned i n yielding only a monophenylhydrazone. I t has apeppermint-like odour, and yields, by the action of alkalis, an acidwhich is easily soluble in water.Dimethylketen combines with tertiary bases to form compoundswhich are generally very stable, and which differ in this respect fromthose obtained from diphenylketen and diphenyleneketen. They areformed by union of two molecules of the keten with one molecule of thebase.By combination with the elements of water, alcohol, or amines,dimethylketen gives rise to isobutyric acid or its ester or amiderespectively :(CH,),C:CO + HR = (CH,),CH*C<g.Wilsmore and A.W. Stewart have made a study of the behaviour ofvarious organic substances when subjected to the action of a heated53 Trans., 1908, 93, 85.xi Ann. Iteport, 1906, 83.5J Abstr., 1907, i, 424.56 Abslr., 1906, i, 43786 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,platinum wire or of an arc burning between carbon or metallicelectrodes, In the cases of ethyl acetate, acetone, and more especiallyacetic anhydride, a gas was obtained which had a peculiar pungent odourand which could be condensed to a liquid by strong cooling.57 Thefirst-named author has now continued the in~estigation,~~ and bringsforward evidence to show that the product mentioned is, as previouslysuggested, keten, CH,:CO. Although the substance bas not beenobtained in a pure condition, the mean results of analysis and molecularweight determinations agree well with this formula.I n its properties,the substance behaves as an internal anhydride of acetic acid. Withethyl alcohol, it yields ethyl acetate and with aniline, acetanilide. Onstanding, especially in the liquid state under pressure, it passes into abrown condensation product.Carbohydrates.Comparatively few papers have been published during the yearwhich deal with the individual sugars. The properties of fucose havebeen further investigated by Mayer and Tollens 59 with the view ofascertaining its configuration. This methylpentose is, as was firstsuggested by Votozek, the optical antipode of rhodeose. The authorsfind that fucose on oxidation with nitric acid yields a trihydroxy-glutaric acid, which is probably iden tical with that obtained byoxidation of d-arabinose.By action of hydrogen cyanide, fucoseyields the lactone of an acid, fucohexonic acid, which acid on oxidation,unlike the isomeric rhamnohexonic acid, yields no mucic acid. Fromthese results, combined with other evidence, the authors consider thatthe following configuration of fucose is completely established,OHH H OHfl 6H 6HHRaffinose was a t one time regarded as an isomeride of lactose, butLoiseau, in 1876, came to the conclusion, from chemical considerations,that it sbould be classified as a trisaccharide. This view was sub-sequently confirmed by de Vries, who determined the ratio of themolecular weights of raffinose and sucrose by his woll-known'' plasmolytic " method.On complete hydrolysis, raffinose yieldsdextrose, laevulose, and galactose, but by slow " inversion," forexample, by means of citric acid,GO it gives rise in the first instance tolaevulose and melibiose.CH,~-~-~--~*CHO.57 h'alurc, 1907, 75, 510.58 Tram., 1907, 91, 1938.See also Proc., 1907, 23, 309.69 Abstr., 1907, i, 588.Pieraerts, Abstr., 1906, i, '729ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 87Neuberg now states that raffinose can be hydrolysed by emulsin,and that the products in this case are galactose and sucrose. This, itwould appear, is the first instance in which sucrose has been obtainedas a product of the hydrolysis of a more complex natural sugar.Since emulsin appears to attack only compounds having P-glucosidestructures, the author considers that raffinose is to be regarded as theP-galactoside of sucrose or as the lmuloside of melibiose.An elaborate investigation is being undertaken by Nef on theprocesses of dissociation in the sugar group, and results are nowgiven 62 of the behaviour of various sugars towards Fehling’s solutionand other oxidising agents.The author had formerly concluded thatthe principal oxidation product, in the cases of dextrose and lzevulose,was d-erythronic acid, but later investigations show that a mixtureof monobasic hydroxy-acids is formed, the separation and identificationof which has been a matter of considerable difficulty. The action ofsodium hydroxide on formaldehyde, diose, trioses, tetroses, pentosesand hexoses was also supposed to yield lactic and erythronic acids.Itis now found, however, that no trace of the latter acid is obtained, butthat, in addition to lactic acid, a mixture of isomeric 6-carbon saccharins,C6Hlo05, is formed. The question arises whether lower saccharins,C,H,O, and C5H804, may not also be produced in the case of tetroses,pentoses, &c. Lactic acid is, according to the author, to be regardedas corresponding with a 3-carbon saccharin :C,H,O, + H,O --+ C3H60,.If, in the reaction under consideration, glyceraldehyde is first pro-duced, the changes may be represented in the following way :HO*CH2*CH(OH)*CH0 t H2O + :CH*CH*OH*CHO --+CH,*CO*CHO,the resulting methylglyoxal then undergoing an immediate rearrange-ment analogous to that of benzil to benzilic acid, r-lactic acid resulting.The formation of the higher saccharins can be similarly explained.Itis shown that when sugars are oxidised in alkaline solution with theoxides of copper, silver, or mercury, saccharins are not produced.Also, that the lower sugars are in this manner directly oxidised andnot, as formerly supposed, first converted into higher sugars.A further account is given by Morrell and Bellars63 on the com-pounds of guanidine with various sugars.64 The general formula forthe compounds with dextrose, laevulose, and mannose is3c6H1206*2N3H5.Abstr., 1907, i, 388.Tram., 1907, 91, 1010.62 ]bid., 1908, i, 5.64 A m . Report, 1905, 8588 ANNUAL REPORTS ON THE PROGRESS OF CHEMLSTRY.They are white, microcrystalline substances, which dissociate to a con-siderable extent in aqueous solution into their components.Theiraqueous solutions show a gradual fall in optical rotation to a minimumvalue which is the same for the three compounds. The authors con-sider that this result, in the case of the dextrose and laevulosecompounds, represents an apparent equilibrium between two sugarsthrough an intermediate substance X, the concentration of which isvery small, D ++- X ++ L, the behaviour being analogous to thatinvestigated by Lobry de Bruyn in the action of alkalis on sugars.There is a slow disappearance of X, the intermediate substance, toform acids. When optical equilibrium has been reached, the ratio oflzevulose to dextrose remains constant until the formation of acidsceases.Mention was made in last year’s Report (page 91) of Schade’s workon the L‘fermentation’’ of sugar to alcohol and carbon dioxidewithout the use of enzymes.The first stage of this operation wassupposed to consist in the breaking down of dextrose or lsevulose intoformic acid and acetaldehyde by the action of alkalis, but subsequentinvestigation showed that this change is of a different nature,glyceraldehyde being probably formed together with furfural, tri-hydroxybutyric acid, &c. The same author points out, howe~er,~5that the second stage, namely, the decomposition of acetaldehyde andformic acid under the catalytic influence of rhodium, has beenexperimentally confirmed, and that an artificial “ fermentation ” maybe regarded as taking place in the following stages.Dextrose, underthe influence of strong alkalis, yields lactic acid (Hoppe-Seyler,Kiliani), and the quantity formed may, according to Duclaux andSchutzenberger, amount to 60 per cent. of the weight of sugar taken.Lactic acid, by action of dilute sulphuric acid, yields acetaldehydeand formic acid, and the two latter substances, under the catalyticinfluence of rhodium, give ethyl alcohol and carbon dioxide. Thechanges mentioned are in each case brought about by a catalyticagency, and the final result is the breaking down of sugar into alcoholand carbon dioxide.The much disputed question as to the maximum acylisationcapability of cellulose has been further examined by Berl andWatson Smith, jun.SS Referred to the simplest formula, C,H,,O,, thehighest cellulose nitrate is the trinitrate ; as regards the acetate, theresearches of Green, Ost, and others point t o the triacetate as themaximum, whereas Cross and Bevan consider that a tetra-acetate canbe produced.The present authors have now studied the formationof aceto-nitrates which are obtained when “ nitrocellulose )’ is treatedwith acetic anhydride and sulphuric acid, The products obtainedb5 Abbtr., 1907, ii, 857. 66 Ibid., i, 289ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 89vary in composition according to the duration of the experiment, andsuch compounds as C,,H2,0,(N0,),(OAc), and C,,H,,O,(NO,),(OAc),were isolated; in no case was a higher acylated compound obtained.It was not found possible to effect by this process the entire replace-ment of the NO, group by acetyl, but the authors hope to do this ina different way.These aceto-nitrates are more combustible than theacetates, and they reach with phenylhydrazine.Wichelhaus and Vieweg 67 describe experiments which, they con-sider, favour the view that difference between cellulose and mercerisedcellulose is a chemical one. The nitric esters obtained under similarconditions from the two substances named, and containing the samepercentage of nitrogen, were found to differ in properties. The yieldof benzoate obtained from cellulose before and after mercerisation isalso found to be different, being considerably greater in the lattercase.The last-named author has also6, examined the action ofsodium hydroxide on cellulose by shaking the material with thealkaline solutions of increasing concentration and titrating theresidual liquid. Plotting the amounts of soda taken up by thecellulose against the concentrations, he finds that two horizontalportions occur in the curve which appear to correspond with thevalues required for the compounds (C,H,,O,),,NaOH and(C6H,,0,),,2NaOH.The amount of soda taken up is, within certain limits, proportional t othe degree of benzoylation by the Schotten-Raumann method, onemolecule of soda being “ equivalent ” to the introduction of two benzoylgroups. Miller Co has carried out somewhat similar experiments, and hedoes not consider that the results obtained can be explained simply bythe formation of chemical compounds in fixed proportions.The xanthogenic esters of cellulose or ‘‘ cellulose thiocarbonates ”have been described in a series of communications by Cross andBevan (1893-1 901).They are obtained by exposing alkali-cellulosehydrate to the action of carbon disulphide at the ordinary temparature,the change being formulated as :ox XONa + CS, = S C < ~ ~ ~ .With iodine, they react in the following way :SC<:$~ + ~ > C S + I, = xi>^^ + 2 ~ a 1 .C. F. Cross, Bevan, and J. F. Briggs7O have now extended theseobservations to a study on the behaviour of starch when submitted tosimilar treatment, certain modifications in detail being necessary in67 Abstr., 1907, i, 186.69 Ibid., 1908, i, 78,68 Ibfd., 893.7 O Tmizs., 1907, 91, 61290 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.order to obtain an intimate mixture of the ingredients.The resultis a xanthogenic ester of starch, which has a composition analogous tothat of the cellulose compound. It is soluble in cold water, and reactswith iodine in the manner above indicated. I n aqueous solution, itundergoes hydrolysis, and the authors find that during thisspontaneous “ reversion ” no starch can be detected by the iodinereaction ; on the addition of a mineral acid, however, the xanthogenategroup is at once decomposed, and the product shows the reactions ofstarch. The persistence of the SC-SNa group in these products mightlead one to regard these residues as measures of the reacting-unit ofthe carbohydrate.The authors, however, prefer to consider thereacting-unit, in the case of such colloidal complexes, as a systemhomogeneous with respect to a particular chemical function, althoughheterogeneous in actual constitution.It is well known that cellulose which has been bleached withoutsubsequent use of an “antichlor ” is found to liberate iodine frompotassium iodide even after exhaustive washing. This oxidisingproperty, which is destroyed by boiling with water or by an anti-chlor,” is considered by Cross and Bevan 71 to be due to a peroxidisedderivative of cellulose. Ditz 72 finds that a simiIar result can beobtained by gradually heating cellulose with an acid solution of apersulphate a t SOo.The product, after thorough washing, is found tocontain about 0.015 per cent. of active oxygen. It also has acidproperties, liberating iodine from a mixture of iodide and iodate ; theacid property appears to be distinct from the active oxidising pro-perties, since it is not destroyed by boiling with water. The productis different from the hydralcellulose which Buncke and Wolffensteinobtained by the action of hydrogen dioxide on cellulose. The celluloseperoxide present in the product is stable only for a short time in themoist condition, but may be kept for some weeks when dried oversulphuric acid after treatment with alcohol and ether.Anhydrides, Acids, and Esters.I n the previous Report (1906, loo), an account was given of theformation and properties of carbon euboxide which was obtained byDiels and WolE from malonic ethyl ester by action of phosphoricoxide.The subject has now been further studied by Diels andMeyerheim,73 and it is found that the compound may be produced ina similar way from other esters of malonic acid (for example, dimethyl-,dibenzyl-, and diphenyl-). Oxalacetic ester and methylenctri-71 Zeitsch. angew. Chem., 1906, 19, 2101.Abstr., 1907, i, 829. 73 Ibid., 180ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 91carboxylic ester when acted on in this way also yield the same carbonsuboxide :C2H,*O*CO*CO*CH,*CO*O*C2H5 = CO + 2C2H, + 2H,O + 0C:C:COCH(CO*O*C,H,), = 3C2H, + CO, + 2H,O + C,O,.The authors further show, as from the first appeared probable, thatcarbon suboxide may be obtained by the direct dehydration of malonicacid itself, instead of the ester, by means of phosphoric oxide :andCH,(CO,H), = 2H20 + C,O,,and this method is now found t o be the most suitable for practicalpurposes.Although a considerable amount of the malonic acid under-goes decomposition into acetic acid and carbon dioxide during thisoperation, the latter products are easily separated from the carbonsuboxide. The acetic acid is mostly retained by the phosphoric oxidebeing changed into other substances. It is found, in fact, that aceticanhydride can be similarly dehydrated, yielding dehydracetic acid.Carbon suboxide solidifies, when appropriately cooled with liquid air,to a mass of large, radiating crystals which melt at - 107" to - 108O.When the vapour is passed through a heated tube, it is decomposedwith deposition of a metallic-looking mirror, resembling that given byarsenic.Whether this deposit consists of pure carbon or an oxygen-ated product has not yet been determined. The vapour of carbonsuboxide readily undergoes polymerisation a t the ordinary temperature,giving a dark red, hygroscopic substance, the change being acceleratedby the presence of impurities ; when heated to higher-temperatures, itbreaks up into carbon monoxide and dioxide.The authors are not inclined to accept the P-hydroxypropiolic-lactone formula for carbon suboxide which was suggested by Michael,74and they consider that the physical and chemical properties of theoxide are best represented by the ' I dioxoallene " formula 0:C:C:C:Owhich they originally proposed.Mixed anhydrides of acetic and boric acids, and of acetic andarsenious acids, have already been obtained by Pictet and hiscolleagues by direct union of the simple anhydrides.Pictet andKhotinsky75 now show that acetyl nitrate, CH,*CO*NO,, may besimilarly obtained. Nitric anhydride is dissolved in acetic anhydride,and the product is purified by distillation under reduced pressure.It is a colourless, fuming liquid, which explodes when quickly heated.In its chemical characters, it closely resembles benzoyl nitrate ; thelatter, it will be remembered, was isolated by Francis, in 1906, bythe action of benzoyl chloride on silver nitrate, It acts as a74 Ann.Report, 1906, 102. 75 Abstr., 1907, i, 17592 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.powerful nitrating agent ; benzene, toluene, anthracene, and thiophencan be nitrated by this means below 0'.Mol76 has prepared anhydrides of the acid esters of dibasic acids byacting with the acid chlorides on the metallic salts of the esters.The chloride, COCl*CO,Et, for example, reacts with the salt,C0,Et *CO,K,to give the anhydride, CO,Et*CO*O*CO*CO,Et. Similar compoundswere obtained from the acid esters of malonic, succinic, and glutaricacids. The compound from oxalic ester on heating is said to yieldcarbon dioxide and ethyl mesoxalate.With the object of gaining further information regarding thestability of closed carbon chains, Perkin and Simonsen 77 havecarried out investigations on the relative ease with which the cyclo-propane and cyclobutane rings are formed in analogous reactions.The nature of this research and the conclusions arrived at will bediscussed elsewhere.In the present section, however, brief mentionmay be made of a n interesting series of acids which the authorsobtained while investigating the action of tribromopropane on thesodium derivative of maloniG ester. The initial compound is shownt o be the ethyl ester of y-bromoallylmnlonic acid,CH,:CBr*CH;C H(CO,Et),.When this is treated with alcoholic potash, it yields a dibasic acid,which has acetylenic properties and which proves to be a butinene-dicarboxylic acid, CHiC*CH,-CH(CO,H), ; this acid is readily de-composed by heat, yielding the monobasic acid,CH iC*CH,* CH,* C0,H.From the latter acid, yy-dibromo- or iodo-valeric acids may beBy acting on the original bromo-ester or on the butinenedicarboxylicobtained by treatment with the respective halogen acids.acid with hy drobromic acid, acetonylmalonic acid,CH,* CO CH,* CH (CO,H),is obtained, which melts at 150' with decomposition into lsvulicacid and carbon dioxide.The original bromo-ester is only reducedwith difficulty, but, when its alcoholic solution is added to moltensodium, allylmalonic acid, CH,:CH*CH,*CH(CO,H),, is produced.Perkin and Prentice, in 1891, when studying the action of methylenechloride on the sodium derivative of malonic ester, obtained as a by-product a yellow, crystalline substance containing sodium.This hasnow been further investigated by T ~ t i n , ~ ~ who comes t o the conclusionthat it is the sodium derivative of dicarboxyglutaconic ester. I t sformation is probably due to the presence of chloroform as an impurityin the methylene chloride employed.i6 Abstr., 1908, i, 76.78 Trans., 1907, 91, 1141 ; and Proc., 1907, 23, 245.i7 Trans., 1907, 91, 816ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 93Alkyl substituted tricarballylic acids were obtained by Bone andSprankling, in 1902, by the interaction of sodium derivatives of cyrrno-succinic esters and bromo-fatty acids in alcoholic solution ; in this way,the mono- and di-methyltricarballylic acids were prepared anddescribed.Henstock and Sprankling 79 have now extended this methodto the preparation of tri- and tetra-methyl derivatives, the initialchanges being represented as follows :CO,Et*CNa(CN)*CHMe*CO,Et + CMe,Br*CO,Et =C0,Et C(C Me,*CO,Et)( CN)* CHMe* C0,Et + NaBrandC0,Et *CNa(CN)* CRle,*CO,Et + CHMeBr*CO,Et =I n this way, but using toluene as solvent, the authors obtained aay-trimethyl- and aayy-tetramethyl-tricarboxylic acids. Attempts t oconvert the trimethyl derivative into a stsreoisomeride were notsuccessful.From ethyl methylsodiocyanosuccinate and ethyl a-bromoisobutyrate,the acid, CO,H*CHMe*CH(CO,H)*CH,*CHMe*CO,H, was obtained,which is isomeric with the trimethyltricarballylic acid previouslymentioned. Evidence is given to show that the two acids arestructurally different, and that they do not represent the two possibleinactive forms of the aay-trimethyltricarballylic acid.Diacetylcarboxylic acid, CH,*CO*CO*CH,*CO,H, may be regardedas the intermediate stage, hitherto missing, between diacetyl anddiketoadipic (ketipic) acid, C0,H*CH2~CO~CO~CH2*~~,H, since thelatter acid yields, as shown by Fittig, diacetyl on dry distillation.Harries and KircherSO have now succeeded in the synthesis of thisacid by the following interesting method.6-Benzylideneltwulic acidis treated in chloroform solution with ozone, and the resulting wax-like mass, presumably the ozonide, is then decomposed by Tvater.The changes which take place may be represented as follows :CO,Et*C(CHMe* CO,Et)(CN)*CMe,*CO,Et + NaBr.The benzaldehyde (and benzoic acid) is removed by extraction withether, and the aqueous solution on evaporation in a vacuum yields thediacetylcarboxylic acid as a thick, yellow oil.The acid is fairlystable, and is not decomposed by continued heating with water. Ityields a characteristic, green copper salt, a bisphenylhydrazone, and abis-semicarbazone. A crystalline oxime could not be obtained ; itsbehaviour in this respect is therefore different from t h a t of theisomeric acid, C'HO*CO*CH,*CH,*CO,F, which Wolff obtained fromdibromolsvulic acid.l9 Trans., 1907, 91, 354. 83 Abslr., 1907, i, 46694 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.It has previously been shown by Le Sueursl that certain mono-hydroxy-acids, when heated to about 270°, decompose into an aldehydecontaining one carbon atom less than the parent acid and carbonmonoxide :R*CH(OH)*CO,H -+ K*CHO + GO + H20.This reaction affords a convenient method of preparing certainaldehydes and of systematically degrading a series of acids.Theauthor has now extended these observations to the dihydroxy-derivatives of dibasic acids and shows that an analogous decompositiontakes place. When, for example, dihydroxysebacic acid, or itsdiacetyl derivative, is heated at about 250°, it yields the dialdehyde ofsuberic acid :CO,H*CH( OH) 0 [ CH&* CH( OH)* C0,H -+CHO*[CH,],*CHO + 2CO + H,O.This dialdehyde mas previously obtained by Baeyer, in 1897, byoxidising the barium salt of dihydroxysebacic acid with lead dioxideand phosphoric acid.It dissolves in water to form a stable solution,but is itself very readily polymerised, yielding a semi-transparentsolid.finds that when the bromine atoms in act'-dibromo-adipic acid are replaced by hydroxyl, two different dihydroxyadipicacids are obtained. Since two asymmetric carbon atoms are present,the author considers that possibly these two acids may be sterea-is0merides.~3With the initial object of synthetically preparing glutaric acid,Zelinsky and Gutt 84 have studied the behaviour of trimethylenebromide in ethereal solution towards magnesium, and the result is notaltogether that which was to be expected, A violent reaction sets in,trimethylene and propylene are evolved, and a product is left whichwhen acted on by carbon dioxide and subsequently hydrolysed yieldssuberic acid.On oxidation, it gives suberic acid,The same authorThe authors represent the change as follows :2Br*[CH,],*Br + 3Mg -+ BrMg*[CH,],*MgBr + MgBr, +CO,H*[C'€€,IJ6*C0,H.Willstitter and VeraguthB6 state that a good yield of suberic acidis obtained when either cyclooctane or P-cyclooctane is oxidised bynitric acid ; P-methyladipic acid is formed also.1 IThe lactone of hydroxycrotonic acid, CH,CH:CH*CO, was preparedby Lespieau from py-dichloro- or dibromo-butyric acids by the actionAnn.Report, 1905, 90. sa PTOC., 1907, 23, 196.B8 Ibicl., 303.83 Compare Rosenlew, Ann. Report, 1904, 72.84 Abstr., 1907, i, 676ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 95of aqueous potassium carbonate. The same author subsequentlyshowed that this lactone when oxidised with barium permanganateyields the lactone of erythric acid, dH,*CH(OH)*CH(OH)*CO 6.Itis now fourid that the latter product is a racemic mixture which canbe to some extent separated by means of the brucine salts. When theladone is reduced by means of sodium amalgam in slightly acidsolution and the product is kept for some months, crystals areobtained which prove to be identical with natural erythritol.An important addition to our knowledge of the constitution ofoxalacetic acid is furnished by the recent work of W0hl.~6 It hasgenerally been the custom to represent this acid and its esters by theketonic formula of Wislicenus, and this constitution, it is true, is con-sistent with its modes of formation and principal transformations.But evidence has not been wanting, on the other hand, which indicatesan enolic structure, and the problem assumes tberefore much the sameaspect as that met with in other familiar cases of tautomerism, such asthat of acetoacetic ester.Briihl, in 1894,87 from spectrometricmeasurements, came to the conclusion that oxalacetic ester must havethe constitution of hydroxyfumaric or hydroxymaleic ester, and asimilar result was arrived a t by Drude88 from observations of theabsorption of electric vibrations of high frequency, Michael 89 hasshown that methyl oxalacetate exists in two forms, but he yet prefersthe ketonic formula and does not consider that the difference dependson a fumaroid and maleinoid configuration.Nef, in 1893, by the saponification of ethyl ethoxyfumarate,obtained an acid, melting at 1 7 2 O , which appeared to be] hydroxy-fumaric acid.that free oxalacetic acid results from the action of water on acetoxy-maleic anhydride or from oxalacetic ester by the action of hydro-chloric acid, but the properties of the acid were not mentioned.Later it was shown91 that oxalacetic acid may be obtained byoxidation of malic acid in presence of ferrous iron.The productprepared in this way melted at 176-180°, and its properties, whichwere exhaustively studied, coincided well with the ketonic formula,although the enolic constitution was by no means excluded.92Wohl and Oesterlin 93 subsequently observed that diacetyltartaricanhydride, when treated with pyridine a t Oo, yields the pyridine'' salt " of hydroxyrnaleic anhydride,Further, it was briefly stated by Michael and BucherAbs.fr., 1907, i, 583, 584.87 J. pr. Chem., [ii], 50, 119.89 Ibid., 1906, i, 179. 8s Abstr., 1897, ii, 537.9o Ibid., 1896, i, 599.91 Fenton, Brit. Assoc. Beprt, 1899 ; Fenton and Jones, Trans., 1900, 77, 77.92 L O C . cit., 83. 93 Abstr., 1901, i, 36596 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.+ Ac,O. /' qH/P\co' FH'OAc+C5H,N = 0O\ YH*OAc \, q(OH)*C,H,N\COWhen this pgridine compound was acted on by dilute (12 per cent.)sulphuric acid and the mixture extracted with ether, a n acid wasobtained which appears to coincide in all respects with that which isprepared by the above-mentioned methods, except that it melted a t146" instead of 176-180".But, by treating the product with30 per cent. sulphuric acid, the authors succeeded in transforming itinto the modification melting a t the higher temperature. The reversetransformation can be effected by heating an aqueous solution of thehigher melting acid with pyridine a t 40-50O. Both of thesemodifications give a t once an intense red colour with ferric chloride,and their solutions, in water or i n acetone, immediately decolorisepotassium permanganate. The molecular refractions of the two acidsare nearly identical, and agree, on the whole, better with the enolicthan with the ketonic formula. The molecular heat of combustion a tconstant volume, however, is greater for the lower melting acid.Theaffinity constants for the higher and lower melting acids respectivelyare 0.276 and 0.25, numbers which differ very greatly from the valueobtained by H. 0. Jones and Richardson for '' oxalacetic acid." 94 Thisdifference, the authors considered, is due to the presence of oxalic andacetic acids in the solution employed in the earlier determination.Taking these and other results into consideration, Wohl arrives a tthe conclusion that the product of high melting point is hydroxy-fumaric acid (m. p. lS4"), and the other, hydroxymaleic acid (m. p.152"). H e considers it probable that the salts have the ketonicconstitution and that, on acidification, the more labile hydroxymaleicacid is first formed according to Ostwald's rule.Wohl and Freund 95 have found that the pyridine compound above-mentioned, when acted on by dry hydrogen chloride in ether, minuteprecautions being taken to exclude moisture, yields the anhydride ofhydroxymaleic acid, This is a crystalline, extremely hygroscopicsubstance, and is converted into hydroxymaleic acid by the action ofwater.By the reduction of ethyl oxalate with sodium amalgam, Lorvig, i n1861, obtained the ethyl ester of desoxalic acid to which the constitu-tion C,H(OH),(CO,Et), mas assigned.It was afterwards shown byDebus that racemic and glycollic acids, as esters or salts, are alsoproduced when the reduction is carried out in alcoholic solution. ThisN I'TCC?~~., 1902, 81, 1158. 95 Alstr., 1907, i, 584ORGANIC CHEMISTRY-ALIPHATIC DIVISION.97reduction has now been further studied by W. Tra~be.9~ Instead oftreating the reaction-product with water, as was previously done, theauthor acidifies it with alcoholic hydrogen chloride, and, after removalof the sodium salt, submits the liquid to fractional distillation. H e isable to prove the formation of the following ethyl esters : desoxalic,racemic, glycollic, glyoxylic, oxomalonic, CO( CO,Et),, and diethyl-glyoxylic, HC(OEt),-C0,Et. The last-named ester is not produceddirectly, but results from the action of the hydrogen chloride on thealcoholate of glyoxylic ester, CH(OH)(OEt)*CO,Et.In order to explain the formation of desoxalic ester, the authorsuggests that one molecule each of glyoxylic ester and oxomalonic estercondense with addition of two atoms of hydrogen :0 , E t F]O,EtHCO HY-OHyO*C02Et H2 = CO,Et*y*OH ’C0,Et C0,E tthe process being analogous to the condensation with reduction of twomolecules of glyoxylic acid to racemic acid.Glyoxylic acid, in the form of its ester, &c., appears t o be the principalproduct in the above-named reduction of oxalic ester, and the processis recommended as a convenient method for its preparation.Reference is also made to the bearing which this reduction has on thequestion of assimilation in plants, and simple explanations, based onwell-established changes, ape offered of the building up of many of thebest known plant acids.The author further shows that glyoxylic ester and rnalonic ester inpresence of acetic anhydride condense to give the ethylenetricarboxylicester of Perkin and Bishop,97 and that the latter on hydrolysis givesrise to fumaric acid and to malic acid.Reference was made 98 to Grun’s investigations on the synthesis ofglycerides.It was mentioned that in the action of sulphuric acid onglycerol, the disulphate is produced even though the acid is employed inlarge excess, the two primary alcoholic groups undergoing esterification.This disulphate reacts with fatty acids to give symmetrical aa-di-glycerides ; but by starting with glycerol a-monochlorohydrin, theremaining primary and the secondary alcoholic hydroxyl groups areesterified and the product can yield up-diglycerides. Grun andSchacht 99 have continued these experiments, and have prepared a con-siderable number of synthetic diglycerides and of mixed triglycerides.It is shown that in the preparation of diglyceridee from glyceryldisulphate, the yield diminishes as the molecular weight of the acidQ6 Abstr., 1908, i, 75.9a Ann.Report, 1905, 83.97 Proc., 1891, 7, 41.99 Abstr., 1907, i, 462.HEP.-VOL. lV. 98 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.employed is lower. It is probable that the resulting glycerides tend tounite directly with the free fatty acid, so that further esterification ischecked, and that this tendency becomes less as the molecular weightof the acid increases.OH*C,H,(O*CO*C,,H27)2,2C~3H27*C0,H,has, indeed, been obtained as the principal product in the interaction ofglyceryl disulphates and myristic acid.Duffy, in 1852, and also Heintz, in 1849, supposed that certainglycerides which show double melting points may exist in isomericforms, and the author now finds that in the triglycerides, p-lnuro-a-distearin, P-myristo-a-distearin, and P-myristo-a-dilaurin, two formsexist in each case.One form is easily soluble and of lower meltingpoint, the other less soluble modification having a higher or double ”melting point.An additive compound-of this kind :Regarding acetoacetic ester as a homogeneous mixture of the twodesmotropic forms, the equilibrium state of which in solution dependson the temperature concentration and nature of solvent, it becomes amatter of interest to study the rate of change from the enolic to theketonic form, or the reverse, under different conditions, Methods ofisolation are, of course, inapplicable for this purpose, and the ferricchloride coloration is, under usual circumstances, inappropriate,since the reagent tend,q t o hasten or even to cause enolisation.Stobbe considers, however, that useful information may be ob-tained from this colour reaction i f the conditions are such thatthe velocity of isomerisation is small, and, working at very lowtemperatures ( - 78O), he has been enabled to compare the velocities indifferent solvents.When amyl, butyl, ethyl, and methyl alcohols areused as solvents, the rate of change from ketonic to enolic form isgreater as the molecular weight of the alcohol is larger. Thisresult indicates that the rate is greater in the less dissociatingmedium, since the dielectric constants of the alcohols mentioned arein the inverse order, that of methyl alcohol being the greatest.2 Bya similar method of observation, the author comes to the conclusionthat the proportion of enolic form is greater in methyl or ethylalcoholic solutions than it is in the liquid ester itself.This resultagrees with the observation of Traube, who studied the change inmolecular solution volume with time when the ester is dissolved.Bruhl, however, by the optical method, concluded that the ketonic formalone is present, not only in the pure substance, but in its solutions inmethyl alcohol, chloroform, or water.Abstr., 1907, i, 177.Compare Wislicenus, Abstr,, 1896, i, 552 ; 1900, i, 9 ; also Federlin, Abdr.,1907, i, 1005ORGANIC CHEMISTRY-ALIPHATIC DIVISION.99Stobbe and Ernst Muller 3 have determined the molecular weightof acetoacetic ester by the cryoscopic method, using chloroformas solvent (m. p. -62’), and the result gives numbers agreeing fairlywell with the unimolecular formula. The authors consider that thelorn reaction velocity at the temperature employed in the above-mentioned experiment is therefore due to the temperature only andnot to the formation of asspciated molecules.Organic acids in which the oxygen of the carboxyl group is entirelyreplaced by sulphur have already been obtained by Houben and hiscolleagues ; to these compounds, the name ‘‘ carbithionic acids ” isgiven. They are prepared by the action of Grignard’s reagent oncarbon disulphide, magnesium phenyl bromide, for instance, yieldingphenyl carbithionic acid, C,H,*CS-SH.These compounds are stronger acids than their oxygen analogues,and are very unstable.They are easily oxidised by atmosphericoxygen, yielding stable compounds (thioacyl disulphides) of the type :So far, only the carbithionic acids of the aryl series had been studied,but Houben and Poh14 have now succeeded i n obtaining similaraliphatic compounds.Methylcarbithionic acid, CH,*CS*SH, is prepared by the action ofmagnesium methyl iodide on carbon disulphide in dry ether anddecomposition of the product with hydrochloric acid. It is a reddish-yellow oil, having an intensely disagreeable odour recalling at the sametime that of mercaptan, ally1 sulphide and acetic acid.It is oxidised byair or by iodine to thioacetyl disulphide.The constitution of fulminic acid and the conditions of its formationstill continue t o engage the attention of chcmists.5 Some further in-vestigations in this direction have now been made by Wieland.6 It wasshown by this author and Semper, in 1906, that phenylmethylnitrolicacid, NO,*CPh:NOH, very easily decomposes into nitrous acid and theunstable benzonitrile oxide, C,H,*CiN:O, of Werner and Buss, If czsimilar decomposition should occur in the case of methylnitrolic acid,NO,*CH:NOH, one might therefore expect to obtain the yet unknownnitrile oxide, H*CiN:O, or products of its transformation, Experi-ment showed, however, that the principal products of its decom-position are formic acid and nitrous oxide, but the author now findsthat,, under suitable conditions, notable quantities of f iilminic acid aro3 Absti.., 1907, i, 178.Ibld,, 352.Compare r l i i i i , Ecporls, 1905, 98 ; 1906, 100.Abstr,, 1907, i, 196.H 100 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.also produced. The change here appears to be analogous to that whichoccurs in the decomposition of chloroformoxime, which was observedby Nef in 1894 :Cl*CH:NOH = HCl+ C:NOH.NO,*CH:NOH = HNO, + C:NOH.It is considered probable, however, that the unstable nitrileoxide, H*CiN:O, is first produced and then undergoes isomeric changeto C:N*OH.I n the ordinary method of preparing fulminates by oxidation ofethyl alcohol, it is probable, the author considers, that the followiDgseries of changes occurs :CH,*CH,*OH -+ CH,*CHO --+ HC(:NOH)*CHO -+HC(:NOH)*CO,H -+ NO,*C(:NOfl)*CO,H -+NO,*C(:NOH)H + C:NOH i- HNO, + CO,.The principal evidence in favour of this supposition depends onPonzio’s observation (1 903) that oximinoacetic acid can be convertedinto methylnitrolic acid by action of nitrogen peroxide, and onWohler’s statement (1905) that acetaldehyde is a more suitable anda more reactive agent for the preparation of the fulminates than ethylalcohol.P a l a ~ z o , ~ on the other hand, states that one of the products of theaction of iiitrous acid on fulminic acid is methylnitrolic acid, that is,nitroformoxime, and considers that this result is in favour of Nef’scarbonyloxime formula for fulminic acid.The older view of Kekul6 that fulminic acid has the constitution ofnitroacetonitrile has now been generally abandoned.The synthesis ofthe last-named compound would, however, be a matter of interest, andt h i s has been the subject of several unsuccessful investigations.Scholl, for example, attempted the synthesis by acting with cyanogenbromide on the sodium derivative of nitromethane and by the inter-action of silver nitrite and iodoacetonitrile. Steinkopf and Bohr-mann8 have recently attempted to obtain the desired result by othermethods, such as the action of phosphoric oxide on nitroacetamide, orthat of bromonitromethane on potassium cyanide, but without success.If cyanoformaldehyde, CN *CHO, were obtainable, it might bepossible by the action of hydroxylamine to produce from it oximino-acetonitrile, CN*CH:NOII, and this on oxidation should yield therequired nitroacetonitrile. The authors therefore attempted to pre-pare cyanoformaldehyde by the action of carbon monoxide on hydrogencyanide, but again without result.They are unable t o confirm thestatement of Bottinger that hydrogen cyanide is a good solvent forcarbon monoxide.Abstr., 1907, i, 489. Ibid., 490ORGANIC CHEMISTRY-ALIPHATIC DIVISION. 101Palazzo and Tamburello have investigated the so-called isocyanuricacid or metafulminic acid which R. Scholl (1896) obtained from mer-curic fulminate by action of sodium amalgam. They show that themolecular weight of the acid, as determined by the cryoscopic methodin acetic acid, corresponds with the formula (CIYOH),.Amino- und Imino-conzpounds.The mechanism of Strecker’s well-known synthesis of amino-acidshas been interpreted in various ways by different chemists.Tiemann,for example, considered that the aldehyde unites with hydrogen cyanide,giving a hydroxynitrile, and this is then acted on by ammonia, formingt h e amino-nitrile. Erlenmeyer, on the other hand, represented thechange as consisting in the action of hydrogen cyanide on aldehyde-ammonia, the latter being regarded as an aminohydroxy-compound.The same author showed also t h a t imino-nitriles may be formed inthis reaction, presumably as condensation products from two moleculesof the amino-nitrile.That ammonium cyanide plays an importantpart in Strecker’s reaction was first suggested by Ljubavin, and hasrecently been emphasised by the work of Zelinsky and Stadnikoff.The last-named author now lo gives reasons for considering that thewhole change may be represented in the following stages :(1) R*CH0,NH3 + HCN = R*CHO + NH,*CN ;(2) NH;CN + H,O - NH,*OH + HCN ;(3) R*CHO + HCN = R*cH(OH).CN ;(4) R*CH(oH).CN + NH3 = R.CH(NH,).CN + H,O.The formation of the imino-nitrile is represented as :R.C!H.CNfi€I +H,O. R C H (OH) C NR.CH(NH,).CN -*That is to say, the hydroxy-nitrile, behaving as a weak acid, reacts withthe amino-nitrile, which, as is known, has basic properties.The author obtains iminodipropionic acid,CH,*CH(C0,H)*NH*CH(C02H)*CH,,by the interaction of a-aminopropionitrile, acetaldehyde, and potassiumcyanide and subsequent hydrolysis of the imiao-nitrile.The yield wasabout 73 per cent. of that required by the above thedry; had theimino-nitrile resulted from condensation of two molecules of amino-nitrile, the theoretical yield would have been less than the actualquantity obtained.Ciamician and Silber 11 point out t h a t this iminodipropionic acid isAbstr., 1907, i, 298. lo Ibid., 393. Ibid., 484102 ANKUAL REPORTS ON THE PROGRESS OF CHEMISTRY.identical with one of the products which they obtained when studyingthe influence of light on the action of a dilute solution of hydrocyanicacid on aldehyde-ammonia.12 Stadnikoff also obtains these imino-com-pounds from the esters of amino-acids an3 hydroxy-nitriles.Alanineester hydrochloride, acetaldehyde, and potassium cyanide, for example,yield iminodipropionic acid, and the iminotricarboxylic acid,CO,H*CH;CH,*CH( CO,H) *NH* CH( CH,)*CO,H,is similarly obtained from glutamic ester and acetaldehyde.Schotten’s well-known method of obtaining amino-acids from cyclicsecondary bases by oxidation of the acyl derivative leads, according to thenature of the acyl group employed, to acids containing the same num-ber of carbon atoms as the base employed or to a lower homologue con-taining one carbon atom less, now publishes a methodby which, from a given cyclic imine, an amino-acid can be obtained con-taining a larger number of carbon atoms in the molecule.The benzoylderivative of the cyclic base, C,:N*CO*CoH5, when acted on by phos-phorus pentachloride or pentabromide, yields the chlorinated amide,J. von BraunC <NH*C0*c6135 , and this can then be made to react with either c1potassium cyanide or with the sodium derivative of malonic ester.I n the first case, the nitrile, C,<CN NH*Co*C6Hs, is obtained, which onsaponification yields the amino-acid, Cz<gEb. The product in the1second case is the malonic ester derivative, C , < ~ ~ ( ~ ~ ~ ~ $ ’ , and thiswhen saponified loses carbon dioxide, giving the acid,The resulting amino-acid contains therefore either one or two atoms ofcarbon more than the original cyclic base according to the mode oftreat men t.Piperidine was in this way, by the nitrile process, converted intoc-leucine, NH,*[CH,],*CO,H, and by the malonic ester treatment to6-amino-n-heptoic acid, NH,*[CH2],*C0,H.Ment,ion bas been made in previous Reports (1905, 75 ; 1906, 107) ofthe interesting work of Windaus and KnoDp, in which it was shown thatmethylglyoxaline results from the action of zinc hydroxide, in presenceof ammonia, on dextrose.The assumption that methylglyoxal is producedand that this is then acted on by ammonia and formaldehyde, is sup-ported by the further observation that, in presence of acetaldehyde, di-methylglyoxaline is obtained.Windaus has now l4 continued the investigation, and has examinedl P Abstr., 1907, i, 19. Ibitl., 524. l4 Ibid., 288ORGANIC CHEMISTRY-ALIPHATIC DIVISION.103the behaviour of various other sugars when submitted t o a similartreatment. Zinc hydroxide, from one part of crystallised zinc sulphate, isdissolved in two parts of 26 per cent. aqueous ammonia, one part ofthe sugar is added, and the mixture is allowed t o stand, in a closedflask, at the ordinary temperature for some months in diffused daylight.Dextrose, mannose, lzevulose, sorbose, arabinose, and xylose all yieldedmethylglyoxaline, and no other ether-soluble base could be detected.Maltose gives a smaller yield than dextrose ; with lactose, it is still less,amounting to about one-fifth of that from maltose and one-twentiethof that from dextrose. Sucrose and raffinose give negative results ; itwould appear in fact that sugars which contain no free carbonyl groupdo not yield methylglyoxaline.When rhamnose is subjected t o similar treatment, the result is a mix-ture of methylglyoxaline and dimethylglyoxaline ; from this result, theauthor concludes that methylglyoxal, formaldehyde, and acetaldehydemust occur as intermediate products.The action of ammoniacal zinc hydroxide on galactose furnishes acrystalline compound, C1,H,,Ol,N,Zn, which reduces Fehling’s solu-tion, yields galactosazone with phenylhydrazine, and on oxidation withnitric acid gives rise t o mucic acid.It is probably a compound ofgalactosamines with zinc hydroxide or -C,H,,05N,C,H1605N2,4H20, zn( OH),*It will be remembered that Lobry de Bruyn and van Leent, in 1895,obtained the compounds C,H,,05*NH2,NH, and C6Hl105*NH2 by theaction of ammonia on galactose.Inouye 15 has also made investigations on the action of ammoniacalzinc hydroxide on sugars other than dextrose, and would appear to havebeen unacquainted with the last publication of Windaus.He statesthat both I-arabinose and d-galactose yield methylglyoxaline. From150 grams of d-galactose, he obtained 15 grams of a zinc compoundwhich, it is stated, yields methylglyoxalinaby treatment with hydrogensulphide, evaporation in a vacuum, and extraction with ether.The only aminohydroxy-aldehydes which have been known up tothe present time are the glucosamines. Wohl and Schweitzer nowshorn that compounds belonging to this class can be obtained from theacetals of unsaturated acids by addition of hypochlorous acid andsubsequent replacement of the halogen by the amino-group.Acral-dehyde diethyl acetal, CH,:CH*CH(OEt),, for example, unites withhypochlorous acid, giving chlorohydroxypropaldehyde ethyl acotal,CH,Cl*CH( OH)*UH(OEt),.This compound is only slowly acted on by ammonia, but the actionmay be greatly facilitated by the addition of potassium iodide. (Thegeneral applicability of this reagent in accelerating the replacementl5 Abstr., 1907, i, 482104 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of chlorine in double decompositions was pointed out by Wohl,*6 andit is considered probable that an intermediate iodo-derivative is firstproduced.)In the present instance, the methyl acetal was acted on byammonia in methyl alcohol in presence of sodium iodide.Theresulting compound, NH,*CH,*CH(OH)-CH(OIMe),, when treatedwith fuming hydrochloric acid, gives the hydrochloride of aminolact-aldehyde, NH,*CH,*CH(OH)*CHO,HCl. It is a crystalline substance,and its aldehydic properties are evidenced by its action on Fehling'ssolution and ammoniacal silver solution, and the formation of a semi-carbazide ; bromine water oxidises i t t o isoserine.Attempts to obtain the free aminohydroxy-aldehyde by acting on thehydrochloride with sodium ethoxide, or with baryta, were not success-ful. In the case of chitosamine, Breuer, in 1898, showed that thefree substance may be obtained from its hydrochloride by action ofdiethylamine. Applying this method in the present case, it was foundthat the liberated aldehyde is unstable ; reaction occurs between theamino- and aldehydic groups, two molecules of the aminohydroxy-aldehyde condensing with loss of one molecule of water and yieldingthe stable anhydro-compound :NH,*CH,.CH(OII)* CH: N *CH,*CH( OH) CHO.This product is a white powder, which dissolves easily in water,giving an alkaline solution.Molecular weight determinations by thecryoscopic method led to interesting results. When first dissolved, thenumbers obtained corresponded with the termolecular formula, but onallowing the solution to stand the depressions of the freezing pointbecame greater. After three days a bimolecular condition wasindicated, and after five days the depression became constantand corresponded with the unimolecular state.This behaviour is verysimilar to that which was observed in the cases of glyceraldehyde 17and of glJvcollaldehyde.l* The cupric reducing power of the solutionalso increases as the molecular weight diminishes, but it does notreach its full value unless the substance is first hydrolysed by acids.Two new synthetical methods of forming isoserine are described byNeuberg and P. Mayer.lg The first method consists in acting onaminoacetaldehyde hydrochloride with hydrogen cyanide in presenceof ammonium hydroxide; in the second method, the authors startfrom ap-dibromopropionic acid, which by action of silver carbonate isconverted into a-bromo-P-hydroxypropionic acid ; this, when acted onwith ammonia and ammonium carbonate under pressure a t looo, yieldsl6 Abstr., 1906, i, 559.1S Fenton, Trans., 1899, 75, 575.l7 Wohl, Abstr., 1899, i, 11.l9 Abstr., 1907, i, 295ORGANIC CHEMISTRY-ALIPHATIC DIVISION.105isoserine. To explain the formation in the way of the p-amino-a-hydroxy-acid, the authors assume the production of an intermediatecompound such as yH2>CH*C0,H, which then unites with the h Helements of water.I t has been shown by Schestakoff 2O that carbamide, when acted onby sodium hypochlorite a t a low temperature, yields hydrazine, andthat substituted hydrazines may similarly be obtained from substitutedcarbamides. The change is compared t o Hofmann’s transformationof amides t o amines, the final change representing a removal of theelements of carbon monoxide.I n the case of the cnrbamides, however,there is, at the same time, a linking of the two nitrogen atoms, and itappeared probable therefore that the type of reaction might be extendedto similar compounds containing more than two nitrogen atoms. Itwas not improbable, for example, that biuret might yield ‘ triazan,’ or‘ prozan.’the phenyl derivative of which has recently been isolated by Dimrothfrom the reduction of phenylazoimide. I n a similar way, one mightpossibly expect t o obtain ‘ buzylen ’ * from hydrazodicarbonamide orazodicarbonamide :NH,*CO*NH*CO*NH, --+ NH,*NH*NH,,NH,*CO*NH*NH*CO*NH, -+ NH,*CO*N:N*CO*NH, -+NH2*N: N*NH,.Working on these lines, Darapsky 21 has studied the action of sodiumhypochlorite on the above-named nitrogen compounds and others, andthe principal results may be stated as follows.With biuret, onlyhydrazine is obtained. Semicsrbazide is completely decomposed withevolution of nitrogen.Hydrazodicnrbonamide,22 by similar treatment, yields eventuallyazoimide. The stages of the operation are represented by the authoras follows. Azodicarbonamide is first formed by oxidation, and thispartly undergoes hydrolysis, giving the sodium -salt of unstable azo-dicarboxylic acid, CO,Na*N:N*CO,Na. Another part is furtheroxidised to triazencarbonamide,NH,*CO*N:N*CO*NH, -3 NH,*CO*N:N*NH,,which, however, undergoes tautomeric change t o the corresponding2o Ann. Report, 1905, 95.* These names were suggested by Curtius for the hypothetical parent substances21 Abstr., 1907, i, 729.22 Thiele, Annatcit, 1892, 270, 1 ; 271, 128.mentioned.Ber., 1896, 29, 781, 782106 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.cyclotriazen; the latter is then oxidised first to carbamazide, whichby hydrolysis yields azoimide :N H NH,*CO*N:N:NH, -+ NR,*CO*N<hH -+NH,*COmN<# N --+ NaN<N. NPhenylsemicarbazide yields eventually phenylazoimide ; aE an inter-mediate stage, phenyltriazen appears to be formed.Polypeptides.I n the limited space of the present Report, it would be hopeless toattempt to convey an adequate idea of the remarkable progress whichhas been made by E. Fischer and his colleagues in their researches onthe polypeptides. The wide range now covered in this field, and the far-reaching importance of the results, would, indeed, justify the clnssifica-tion of the subject as a separate department.It may be of interest,however, to refer briefly to a few of the more recent results with theobject of indicating some of the directions in which the research hasdeveloped.The synthetical process of building up complex polypeptides bylinking together, step by step, the residues of amino-acids has beensteadily continued. I n the previous Report (1906, 112), the isolationof a dodecapeptide, leucyldecaglycylglycine, was announced. I n thepresent year, Fischer has described a tetradeca- and an octadeca-pe~tide,~3 the molecular weight of the latter being higher than that ofany synthetical product of known constitution which has yet beenobtained.Fischer sees no reason, apart from the cost and trouble,why the process should not be continued to a much higher stage. Butit is considered more important to concern oneself with the synthesisof polypeptides from a large number of different amino-acid residues,and which contain, if possible, no contiguous groups of the same kind.Active forms of the amino-acids are to be preferred to the racemicmodifications, for the reason that stereoisomerism is escluded ;the synthetical process is thus simplified, and the products are morelikely to resemble the natural substances.Four new complex polypeptides are described by Fischer 34 whichhave been built up from the residues of glycine and 1-leucine, contain-ing respectively eight, ten, fourteen, and eighteen amino-acid groups.Triglycylglycine, NH,*CO-NH*[NH~CK,~CO],*NH*CH,*CO,H, reacts23 “Octadeca” is used i n place of “octokaideca” for the sake of uniformity.Compare Fischer, Ber., 1907, 40, 1755.24 Abstr., 1907, i, 485ORGANIC CHEMISTRY -ALIPHATIC DIVISION.107in the cold, in presence of sodium hydroxide, with the chloride ofd-a-bromoisohexoyldigl ycyl g l y ~ i n e , ~ ~CHEr( C,H,) 0 *[NH*C €€,a CO],*NH C H2* CO,H,to give d-a-bromoisohexoylhexaglycylglycine. The latter, when actedon by liquid ammonia, undergoes Walden's rearrangement, and yieldsthe octapeptide, Z-leucylhexaglycylglycine,NH,*CH( C,H,)*CO*[NK* CH,*CO],*NH*CH ,*CO,H.By starting with pentaglycylglycine in placa of triglycylglycine andproceeding in a similar manner, the decapeptide, Z-leu~yloct~aglycyl-glycine, NH,*CH(C,H,)*CO*[ N H*CH2*CO],*NH*CH,-C0,H, is ob-tained.This again reacts with the bromoisohexoyldiglycylglycinechloride in presence of soda to give d-cc-bromoisohexoyltriglycyl-l-leucyloctaglycylglycine, which: by action of liquid ammonia, is trans-formed into the tetradecapeptide, Z-leucyltriglycyl-Z-leucyloctaglycyl-gl ycine, NH<h€( C,H,) CO.[NH*CH,*CO],* NH* CH2* C0,H'C 0 C H N H] CO C H ( C,H R) N H ,This last-named peptide is then acted on by the bromoisohexoyl-diglycylglycine chloride, and the product treated with liquid ammoniaas before, when the octccdecapeptide, Z-leucyltriglycyl-Z-1eucyltriglycyl-Z-leucyloctagl ycylglycine,CH(C,H,)*NH*[CO*CH,*NH],*C0*CH(C,H,)*NH2 70,HCo<[NH*CH,*CO],-NH* CH( C,H,)* COB[ NH* CB2* CO],*NH*CH, 'is obtained.These four polypeptides are all obtained as colourless, indistinctlycrystalline powders. The octapeptide is the most soluble in water,and the decapeptide the least solubIe. I n many of their properties,they so closely resemble the ordinary proteins that they would cer-tainly have been classified as such if they had been found in naturalsubstances. They all give a very strong biuret reaction, and are pre-cipitated by phosphotungstic acid. They do not show the xantho-proteic reaction, nor the reactions of &Tillon or Adamkiewicz, sincethey contain neither tyrosine, tryptophan, or cystine. They formsparingly soluble sa1t.s with mineral acids. The warm clear solutionsof the tetradeca- and octadeca-peptides become opaiescent whencold, 2nd are precipitated by a strong solution of ammonium sulpbateor by tannic acid. It will be seen from the formula given that themolecuIar weight of the octadecapeplide is 1213. It is pointed outthat if a similar synthesis were carried out with the substitutionof the residues of phenylalanine, tyrosine, cystine, &c., for glycyl,the molecular weight of the resulting peptide would be two or threeAbstr., 1906, i, 808108 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.times as great, and would reach the value which has sometimes beenassumed for certain natural protein substances.Many polypeptides have been isolated among the decompositionproducts of natural proteids. From the products of the partialhydrolysis of silk fibroin, for example, glycyl-d-alanine and glycyl-tyrosine have been obtained ; in addition to tbess, a tetrapeptide,probably derived from glycine, alanine, and tyrosine, bas been isolatedwhich shows remarkable resemblance to the albumoses. The lattercircumstance led Fischer 2o to study some of the higber syntheticalpolypeptides containing tyrosine, and two such compounds are describedwhich appear to be of great interest. They are d-alanylglycyl-Z-tyrosine and Z-leucyltriglycyl-Z-tyrosine. The latter pentapeptide isobtained by acting on Z-tyrosine with the above-mentioned bromo-isohexoyltriglycgl chloride, and treating the resulting bromoiso-hexoyltriglycyl-Z-tyrosine with ammonia. It is easily precipitatedfrom its aqueous solution by ammonium sulphate, and from itsslightly acid solution by a concentrated solution of sodium chloride.It is also precipitated by phosphotungstic acid and by tannic acid,and gives a strong biuret reaction and Millon's reaction. In all itsproperties, in fact, it very closely resembles the albumoses.The molecular weights of several polypeptides have been determinedby the cryoscopic method in aqueous solution. Bearing i n mind thefact that glycine yields normal results with this method, it was t o beexpected that the simpler polypeptides would behave similarly.Although this is generally found to be so, the deviations from thenormal are greater than in the case of glycine, and the observedvalues for the molecular weight are always smaller than thosecalculated from the formuls. Triglycylglycine, for instance, gives178 to 188 instead of 246, but this may possibly be due to thesmall concentration employed, the substance being sparingly soluble.The diketopiperazine, glycyl-d-valine anhydride,has a remarkable tendency to separate from its solutions in agelatinous condition, and one might naturally expect from thiscircumstance that its molecule would be complex. But theresult of cryoscopic determination shows that this is not thecase ; the value found being 138, whereas the formula given requires156. H. J. H. FENTON.26 Abstr., 1907, i, 901

ISSN:0365-6217    

DOI:10.1039/AR9070400074

出版商:RSC    

年代:1907

数据来源: RSC

摘要:

ORGANIC CHEMISTRY-HOMOCY CLIC DIVISION.IN the enormous and continually increasing output of investigationsin organic chemistry there is considerable difficulty in recognising andindicating the general lines along which progress is taking place. Alarge number of the investigations carried out in any given year areisolated in character, having as their object the solution of some im-mediate problem, without reference, expressed or implied, to anygeneral theoretical scheme. This fact makes i t impossible to give asurvey of such a field as t h a t of the homocyclic compounds which shallembrace all or even the gre-iter part of the work abstracted during thepreceding year. The most t h a t is possible is to select such researchesas lend themselves to grouping about a few main lines of investigation,especially such as have a wider bearing than on the special problemsunder examination.Although there may be differences of opinion ast o the relative importance of the various tendencies to be observed inrecent work, yet it would seem that certain questions stand out withsufficient prominence to justify their selection.The problems of the relations between colour and chemical constitu-tion, of the nature of isomeric change in aromatic derivatives, of thestructure of the benzene nucleus, and of the conditions of formation ofrings, are not only of great intrinsic importance, but their solution isnecessary before the f undamentlzl principles of organic chemistry canbe ragarded as satisfactorily established. Researches into the constitu-tion and synthesis of certain groups such as the terpenes also possessa more than specialinterest from the remarkable relationships exhibitedby some of their members, and from the ingenuity of the methods towhich their experimental stiidy has given rise.The diazo-compoundsand hydrazones, again, apart from their many practical applications,derive much of their interest from the difficulty of finding formulaecapable of expressing the whole of their chemical behaviour, a difficultywhich has led to prolonged controversy. The same may be said oftriphenylmethyl, the investigation of which has occupied many workersfor a considerable time without entire agreement as to its constitutionhaving yet been reached. It may be said that the insufficiency ofpurely statical formulae is being felt more and more acutely, and suc110 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.conceptions as those of taut omerism and dynamic isomerism are constantlyassuming greater importance, That this theoretical change must ulti-mately lead to a more intimate contact between organic chemistry andphysics can hardly be doubted, but a t present the points of contact ofthe two sciences are comparatively few and scattered.In spite of the increasing use which is made of measurements of suchphysical constants as the refractive index and magnetic rotation asguides in the determination of structure, the application of physico-chemical methods, especially those of chemical statics and dynamics, toorganic problems is still very restricted.Isolated examples during thepast year have been the comparative measurement of the velocity ofesterification of substituted benzoic acids and an attempt to decidebetween the possible intermediate products in the oxidation of naph-thalene t o phthalonic acid by potassium permanganate,2 and of P-naph-thaquinone to phthalic acid by potassium dichromate.3 The methodadopted in each case was to measure the velocity of oxidation, underthe given conditions, of each of the compounds which might conceiv-ably appear as an intermediate stage in the reaction. Determinationsof the velocityof hydrolysis of esters, &c., when the object is not thestudy of structure, belong rather to the department of physicalchemistry.There has been no revolutionary introduction of new reagents t orecord during the past year, and such improvements of detail as needt o be mentioned may be treated under their respective sections, Themultitudinous applications of Grignard’s reaction have been usefullysummarised by A.McKeuzie in a report laid before the British Associa-tion at its Leicester meeting. Among recent tipplications, the action ofGrignard’s reagent on oximes has been shown 4 to be the replacementof hydroxyl by alkyl, followed by the formation of an additive com-pound, which is then hydrolysed :R*CH:N*OH + 2RMgX -+ g,>CH*N<EgX + E,>CHNHR’.The same product is obtained from the O-ethers of the oxime.Xtructure of Benzene.There has been a marked revival of interest in the problem of theconstitution of the benzene nucleus, and the relative advantages of thecentric and Kekuld formulte.On the one hand, the properties of ozoneA. Kailan, Abstr., 1907, i, 849 ; ii, 168, 242, 243, 853,R. A. Daly, ibid., 1907 i, 407,31. C. Boswell, ibid., 407.M. Uusch and R, Hobein, ibid., 535ORGANIC CHEMISTRY-HOMOCYCLIC DIVISION. 111as a reagent for the detection of ethylene linkings have been utilised.Unfortunately, the results with benzene itself are as yet inconclusive.The existence of Harries’ triozonide of benzene which was cited insupport of the Kekuld formula, is denied by Molinari,G who finds thatbenzenoid compounds do not react with ozone, whilst quinonoid deriva-tives manifest the existence of ethylene linkinga in the nucleus by theformation of ozonides.Phenols react as if quinonoid in structure,which is in accordance with many other facts indicating at least thetransient existence of the tautomeric form. Theoretical arguments infavour of the centric formula for benzene have also been adduced 7 fromthe reactions depending on the polymerisati n of aliphatic compounds.On the other hand, a body of new facts has recently been broughtforward in support of Kekuld’s formula. The old objection to it, thati t indicated the existence of isomeric ortho-di-derivatives, has nowbeen converted into an argument in its favour. It has been known forsome time in technical practice that o-nitrotoluene exists in two distinctcrystalline modifications, having different melting points.It is nowfound * that these are not merely polymorphic crystalline conditions ofthe same substance, but that they also differ in the liquid state, havingdifferent depression constants, and depositing their correspondingcrystals when cooled after long storage in closed vessels. There seems,then, to be some justification for regarding them as true isomerides.Similar modifications have been observed in o-chloro- and bromo-toluene,o-toluidine, o-chlorophenol, o-chloroaniline, and 2 : 4-dinitrophenol.Knoevenagel’s hypothesis of motoisomerism would call for the exist-ence of isomerides in the para and meta series also, and would even in-dicate the possibility of two isomeric mono-derivatives when the sub-stituting group is asymmetric, a suggestion which the author considersto derive support from the fact that freshly distilled nitrobenzene hasa different viscosity from that which has been kept, Although thefacts may be susceptible of more than one explanation, an interestingfield of investigation is opened up by them.There have also been several theoretical attempts 10 to form a con-ception of the benzene nucleus capable of accounting for the orienta-tion of substituting groups, but the views contained in these papers donot lend themselves to summarisation in a report.I n the absenceof any clear physical conception of the nature of valency, there isalways a danger that theories of the valency of Ghe carbon atom,devised ad hoe for the purpose of explaining organic reactions, mayAnn.Report, 1906, 120.7 It. Vidal, ibid., 1020.I. von Ostromisslensky, ibid., 120, 696 ; E. Knoevenagel, ibicl., 202.Abstr., 1903, i, 785.E. Molinari, Abstr., 1907, i, 1039.lo J. Obermiller, ibid., 1907, i, 200 ; B. Fliirscheim, ibicl., 835112 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.prove on examination to be merely rest,atements in other language ofthe problem to be solved.Colour and Constitution.The Annual Reports for the last three years have made referenceto the growing interest in the question of the relation of colour tostructure. The desire to contribute to the solution of this problemhas been the motive of a large number of recent researches, andalthough the relation is still very imperfectly understood, yet withintho limits of certain groups it is possible to establish rules for theappearance or non-appearance of colour. It is now generally recog-nised that a more precise meaning must be given to the idea of colourthan has often been the case.The production of physiological colour,due to the occurrence of absorption in the visible spectrum, is more orless an accidental circumstance. Absorption bands may occur in theultra-violet of equal importance with those in the visible spectrum,I n some cases a change in the frequency of the absorbed rays maycause a band to move from t h e ultra-violet into the visible regionwithout any change of form. A colourless substance may thereforebe converted into a coloured one without any real change in constitu-tion having taken place, the alteration in the molecule being only ofsuch a nature as to cause a certain retardation of those oscillationswithin it which give rise to the absorption.A study of the colour of a substance thus involves the examina-tion of its entire visible and ultra-violet spectrurn,ll and further, asHartley and his successors have shown, of the change of absorptionwith the concentration of the absorbing substance, the results beingbest expressed in the form of curves.The quantitative study of theabsorbing power of a substance, expressed in this manner, makes anexact comparison of different derivatives possible, and relationshipsace made evident which would escape notice i f the examination wereconfined to visual observations of colour.It is therefore not sur-prising to find an increasing use of spectroscopic methods in theliterature of organic chemistry.Several different explanations of the origin of colour are offered atthe present time, bat these explanations are not mutually exclusive,and in the case of certain compounds two or more of the rivalhypotheses meet on common ground. From one point of view, colouris ascribed t o the presence of a quinonoid structure in the molecule(Armstrong, Gomberg, R. Meyer, and others), from another, to theentrance of certain groups, the auxochromes, into a sensitive molecule,l1 The absorption bands in the infra-red appear to have a different origin, andmay be neglected for the purpose of the present discussionORGANIC CHEMISTRY-HOMOCYCLIC DIVISION.113the chromophore (Kauffmann).12 When a coloured compound is pro-duced from a colourless one, as for instance by solution or by salt-formation, this is explained by a particular form of ionisation (Baeyer)or by a molecular arrangement giving rise to a quinonoid or otherlinking characteristic of colour (Hantzsch). The more definitelyphysical theory of Baly regards banded absorption as produced byoscillatory changes of linking within the molecule, due to the con-jugation of groups possessing residual affinity. Whilst, therefore, onthis view the quinonoid structure is only one phase in an essentiallydynamical process, the auxochrome theory is not rejected, but anattempt is made to provide a physical basis for the properties of theauxochromes.Nitroquinol dimethyl ether, the colour of which was disputed,13 hasnow been shown to be yellow when pure.14 Its solution in lightpetroleum is colourless, its other solutions being more and more yellowwith increasing dielectric capacity of the solvent.15 Since both theyellow colour and the molecular weight increase with the concentra-tion, the yellow solutions are regarded as additive compounds.Thecolour is much less intense than that of nitrophenol salts, and is notconsidered by Hantzsch to demand the assumption of molecularrearrangement.A remarkable series of coloured alkali salts of nitro-compounds hasbeen investigated by Hantzsch and his co-workers. Under differentconditions of temperature i t is possible to obtain both red and yellowsalts of the nitropheho1s.l6 The product is often orange, consistingof mixed crystals of the two i+omerides, which may be separated bycrystallisation in absence of water.The red and yellow potassiumsalts of 2 : 4 : 6-tribromo-3 : 5-dinitrophenol both undergo gradualchange in solution until a condition of equilibrium is reached; inother cases one of the salts is only stable at -75’. Structuralisomerism is discussed and rejected, the author preferring to representt.h0 two classes of salts as syn- and anti-stereoisomerides, as :C,H,*O \I NO,MRed.C,H,*O ‘ I \MO,NYellow.Although mononitro-compounds form only colouriess salts, dinitro-compounds, such as phenyldinitromethane, yield both red and yellowl2 For a summary of this question, see H.Kauffmann, “ Die Auxochrome,”Bee also J. Schmidt, (‘ Chinone und Chinoide Ahrens’ Sammlun,g, 1907, 12, 1-3.Verbindungen,” ibid., 1906, 11, 10-11.Ann. Report, 1906, 147.l5 A. Hantzsch, ibid., 513.REP.-VOL. IV. Il4 H. Kauffmann, Abstr., 1907, i, 127.A. Hantzsch, ibid., 207114 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.salts.17 Both modifications retain their colour when dehydrated, butyield identical equilibrium mixtures in solution, which are found to beunimolecular. The presence of the second nitro-group is necessary,since bromonitromethane and phenylcyanonitromethane,CN*CHPh*NO,,form only colourless salts. Evidence is brought forward to show thattrue aci-salts, R*C<g%M, are colourless.When only one of thenitro-groups is in the methane residue, the other being in one of thephenyl groups, as in the nitrophenylnitromethanes, two colourless andfour coloured isomerides are possible. The colourless salts, of whichonly the mercuric salt of m-nitrophenylnitromethane has yet beenisolated, would have the formula :NO,*CGH, *CH:NO,M and N0,M:C6H4: CH*NO,.The compiete series of four chromo-salts, yellow, red, green, andviolet, has been isolated in the case of the potassium salts of p-nitro-phenylnitromethane. In the formation of the coloured derivatives,both nitro-groups must take part, and the following structures areregarded as the most probable, the dinitroparaffins being selected asthe simplest example :0:Bf.o O:N?OR*C==N*OJI R* C*NO,M(111.)I 0 4 II I NO2 1R*C:NO,MColoured.(1.) (11.1Colourless, representedby the ether.Of these, both (11) and (111) may exist in two stereoisomeric modifica-tions. Isomeric chromo-salts have also been obtained from nitro-barbituric acid and similar compounds.l* Since, however, the halogen-phenols, to which such structural formulae cannot be applied, yieldboth coloured and colourless silver salts,lg the isomerism in questionevidently demands further investigation.It will be observed that the formulae which Hantzsch now employs torepresent the coloured derivatives are not strictly quinonold, butcorrespond rather with the 4' peroxide " formula for quinones.Thushe assigns to the coloured salts of hydroxybenzaldehyde and methyldihp droxyterephthalate the respective structures :l7 A.Hantzsch, dbstr., 1907, i, 500.l9 H. A. Torrey and W. H. Hunter, ibid., 1030 ; A. Hantzsch, ibid., 1908, i, 17.1s A. Hantzsch, ibid., 555ORGANIC CHEMISTRY-HOMOCYCLIC DIVISION. 115The fact that these compounds are fluorescent is opposed to aquinonoid structure and indicates the presence of an unalteredbenzene nucleus.20 In connexion with this point it should bementioned that the tautomeric quinonoid constitution,has been assigned to salicylic acid in order tofrom sodium phenoxide,21 and its formationNHPhoN:C6H4<Co2H.22 Hexplain its productionof a phenylhydrazone,By the action of ethyl iodide on the dry silver salts a t lowtemperatures, coloured quinonoid derivatives of phenolphthalein andtetrabromophenolphthalein have been obtained.28 Hitherto thequinonoid esters have only been prepared by acid alkylation.Theyreadily undergo isomeric change to the colourless Iactone ethers :76"4*s0 o----0\/\\A f I I I:()O E t V \/Phenolphthalein forms a red-+ N\/\OEd,) ()Ethydrochloride at - 30°, which decom-poses as the temperature rises, but stable red stannichlorides arereadily obtained from phenolphthalein (I), the quinonoid ester (11),and the lnctoid dimethyl ether (111) : 24Similar formulae are proposed by Green and King, who representthe coloured alkali salts of the ester thus :25C,H4*ONaOH H>o:c6H4:c<c 6 4 H .CO,Me'It is, however, argued by Baly26 that such oxonium compounds2o H.Kauffmann, Abstr., 1907, ii, 214, 215 ; A. Hantzsch, ibid., 418,21 K. Brunner, ibid., i, 319.22 H. Schrotter and J. Flooh, ibid., 929.23 R. Meyer and K. Marx, Abstr., 1907, i, 421, 932 ; H. Meyer, ibid., 625.24 K. H. Meyer and A. Hantzsch, ibid., 932.25 8. G. Green and P. King, ibid., 933 ; Proc., 1907, 23, 228.would be colourless.According to H. Meyer, however(Monatsh., 1907, 28, 1381), the compound is the phenylhydrazide.PYOC., 1907, 23, 229.1 116 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.As in recent years, the battle of the colour theories has been largelyfought on the field of the triphenylmethane compounds. Whilst Baeyerconsiders that yuinonoid structures are not the specific cause of colour,but merely facilitate its appearance, since they allow weaker auxo-chromes to exert their influence, Gomberg now maintains the quinonoidconstitution of all the coloured derivatives, modifying it to the extentof considering the grouping as the only essential part of thequinone ring, since the linking of the upper carbon atom to a bivalentelement is absent both from these compounds and from the fulvenes.Gomberg finds 27 thak solutions of triphenylmethyl chloride and itsderivatives in benzene react with silver sulphate to form colouredsulphates.When para-halogen is present, one atom of this is alsoremoved, which he considers to be evidence of the quinonoid structure.According to Baeyer,2* however, the slow removal of ring-substitutedhalogen is due to a destruction of the molecule, as is shown by the factthat an odour of quinone is observed, whereas the diphenylquino-methane, O:C:,H,:CPh,, which should be formed on Gomberg’ohypothesis, is without odour.The point was tested by a comparisonof the ferrichlorides of tri-p-chlorotriphenylmethyl bromide and tri-p-bromotriphenylmethyl chloride :II I1II(C,H,Cl!,C:C,H,<~~,FeCl, and (C,H,Br),C:C,H,<GCf,FeCl,.The quinonoid portions of the two molecules are identical, and shouldyield the same halogen with water. The former, however, loses onlybromine, and the latter only chlorine. Similar results were obtainedwith the corresponding stannichlorides by Tschit~chibabin,~~ who alsofound that Gomberg’s coloured solutions of the chlorides in liquidsulphur dioxide, heated at 50°, and then decomposed with alkali, gaveonly chloride without any trace of bromide, whilst the formulawould require the formation of both chloride and bromide.Thequinonoid thoory is, however, supported by other investigttt~rs,~~ andformulz of this type have been applied to the coloured salts of thep-aminocinnamylidene derivatives of acetic and malonic acids,31 as :NH,c~:/=\:cH*cH: CH~CH (co,~),. \=/~7 M. Gomberg, Abstr., 1907, i, 504.A. E. Tschitschibabin, ibid., 1022.30 F. Kehrmann and F. Wentzel, ibid., -601.y1 H. Fecht, ibid., 926.A. von Baeyer, ibia., 691ORGANIC CHEMISTRY-HOMOCYCLIC DIVISION. 117Whilst Gomberg attributes an exactly similar constitution to the saltsof pararossniline with one equivalent of acid :/=\(NH;C,H,),C:/ \: NH,CI, \=/Baker, from a study of their absorption spectra,32 is led t o representthem as carbonium compounds :An extended study of the hydroxy- and amino-derivatives oftriphenylmethane and their salts has led Baeyer (Zoc.cit.) to the con-clusion that an oscillation between two forms, similar to that describedby Baly as isorropesis, is the origin of the absorption band. If, forinstance, two of the benzene rings, a and b, in triphenylmethane con-tain each a hydroxyl group, then either a or b may become quinonoid,and one form may pass into the other without change of properties.I n the sodium salt of benzaurin, then, there would be a continuousoscillation between the forms :I IPh P hI n Doebner's violet there would be a precisely similar oscillation ofthe chlorine between the two NH, groups, with corresponding changeof linking.The fact that crystal-violet behaves as the salt of a strongrnonoacid base,33 whilst the carbinol is only a weak triacid base, isintelligible if the three amino-groups have the same function and aresaturated alternately.The difficulty of finding any statical arrangement of bonds whichwill invariably produce colour is further illustrated by some investiga-tions of ~ x i r n e s . ~ ~ Phenanthraquinonedioxime and its sodium salt arestrongly coloured, but its dime€hyl ether, diacyl derivatives, andanhydride are all colourless, although the quinonoid configuration isC Hstill intact. Fluorenoneoxime, I '>C:NOH, and its sodium saltC,Hd - -are coloured, the acyl derivatives are paler, but still yellow, but themethyl ether is actually darker in colour.A comparison of thecorresponding derivatives of o-benzoquinonedioxime and P-naphthn-yz F. Baker, Trans., 1907, 91, 1490.$4 J. Schmidt and J. So11, ibid., 1907,, i, 630, 1054.33 A. Hantzsch, Abstr., 1900, i, 365118 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.quinonedioxime35 has shown that the colour is greatly dependent onthe solvent, and the following types of formulae are suggested :Colourless. Faintly coloured. Strongly coloured.The influence of substituents, especially hydroxyl, on the isorropesisof quinones has been studied spectroscopically in the case of naphth-acenequinone.36Benzoic acid has an absorption band in the ultra-violet, which isalso present, though considerably narrower, in the spectra of potassiumand silver benzoates.Phthalic acid bas a wider band, bophthalicacid has a shallow band in the same position, terephthalic acid doesnot show a band.37Triphen y lrnethy l.The controversy, discussed in previous Reports,38 as to the con-stitution of triphenylmethyl still continues. The view that the solidcompound is to be regarded as hexaphenylethane, has been criticisedas being inconsistent with the stability of tetra- and penta-phenyl-ethane. Pentaphenylethane, however, although stable at the ordinarytemperature, becomes unstable when its solution is heated, splitting upinto diphenylmethyl and triphenylmethyl groups, which are thenreadily oxidised.39 The result found by H a n t z ~ c h , ~ ~ who failed toobtain hexanitroethane from iodopicrin, favours the view that theaccumulation of negative groups in the ethane molecule tends towardsinstability, The stable hexaphenylethane, supposed to have beenobtained in an impure state from magnesium triphenylmethyl chlorideand triphenylchloromethane,41 is now considered 42 to be impure tetra-phenylethane.Solid triphenylmethyl is colourless, remaining unchanged forseveral months in dry air.43 Its solutions are yellow, and hence adifferent constitution is required for the solid and the dissolved sub-stance.The evidence is now strongly in favour of the hexaphenyl-ethane formula for the solid compound, but no definite conclusion has35 A.Hantzsch and W. H. Glover, Abstr., 1907, i, 1055,36 E. C, C. Baly and W. B. Tuck, Trans., 1907, 91, 426.37 W. N. Hartley and E. P. Hedley, ibid., 314, 319.38 Anit. Xeport, 1904, 105 ; 1905, 117 ; 1906, 131.39 A. E. Tschitschibabin, Abstr., 1907, i, 204.40 Ibid., 1906, i, 617.41 J. Schmidlin, ibid., 1907, i, 27.42 Tschitschibabin, Zoc. cit.43 A. E. Tschitschibabin, ibid., 691ORGANIC CHEMISTRY-HOMOCY CLIC DIVISION. 119yet been reached as to its condition in solution. The existing rivalviews have been summarised by Tschits~hibabin.~~(1) 66Halochromy,” or colour due t o ionisation, may be assumed.Thus, in accordance with Baeyer’s notation, dissolved triphenylmethylwould be written CPb,-CPh,. This, however, really only restatesthe fact without providing any explanation.(3) Gomberg suggests that the dissolved substance has the formula CPh2:C6€K4<~p,d which partly dissociates into a quinonoid cationand a benzenoid anion.He does not, however, finally decide betweenthis hypothesis and the existence of the free triphenylmethyl radiclein solution, which is in some ways to be ~referred.~5(3) Quinonoid formula, such as those of HeintscheI and Jacobson,46may be written for the coloured modification. The final decisionbetween these views is not yet possible.Against the formulse of Gomberg and Jacobson, it has been urged 47that the compound (I) would be so unstable as at once to change intothe isomeride (II), and in support of this the behaviour of palkyl-Ph2CHH-N *CPh, \=/idenedihydrobenzenes 48 is quoted, the quinonoid configuration in (111)being so unstable as to pass spontaneously into the stable benzenoidform (IV), although in this case the wandering of so heavy a groupas .CHCI, is involved :(III.)The magnesium compound of triphenylmethyl chloride has beendescribed49 as existing in a yellow quinonoid and a colourless benz-enoid modification, but the experiments of Tschitschibabin 50do not confirm the existence of chemical isomerism in this case, a sthe behaviour of the two preparations is found t o be similar, thestatement that the yellow form does not yield triphenylacetic acidwith carbon dioxide being incorrect.44 J.pr. Chenz., 1907, [ii], 74, 340.48 K. Anwers, Abstr., 1907, i, 399.45 M. Gomberg, Abstr., 1907, i, 514.47 K.Auwers, Ber., 1907, 40, 2159.4g J. Schmidlin, ibid., 1907, i, 26, 601.Ann, lieport, 1906, 132.Abstr., 1907, i, 1022120 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.D iazo-compounds.The usual representation of diazonium compounds by Blomstrand’sformula, and of the diazotates, diazo-cyanides, &c., as s tereochemicallyisomeric azo-compounds, has long been recognised as presenting diffi-culties. The Blomstrand formula (I) especially fails to indicate thegreat readiness with which the diazonium salts lose their nitrogen.Since a nitrogen atom directly attached to the benzene nucleus, as inaniline, is generally very firmly retained, it might be expected thatdiazonium salts would only lose one atom of nitrogen instead of bothas is actually the case.The nitrogen atom of aniline is, however,easily removed by oxidation, the product being p-benzoquinone. Sincethis reaction probably proceeds through quinoneimide as an inter-mediate product, there is some justification for considering thataniline reacts in this case in the tautomeric quinonoid form (11) :(1.1 (11.)These facts have suggested the formulation of diazonium salts asquinonoid derivatives,51 diazobenzene chloride having the formulaH\/-\:N*Cl. I\-./ ” --NI n the elimination of nitrogen, as in the action of water, rupturenaturally tends t o occur at the double linking. A considerableamount of evidence is adduced in favour of this formula.Thus the production of a nitrosodiazonium compound by the actionof nitrogen peroxide on thymoquin~nedioxime,~~ is best accounted forby considering the quinonoid configuration as remaining intact :N-OHNO\*.: \-,N* OH NO,*g:N-IFurther, whilst ar-tetr~hydronaphthylamine and 5-aminoquinolineare diazotisable, ac-tetrahydronaph thylamine and 4-aminoquinoline, inwhich the quinonoid formation is no longer possible, do not yield51 J.C. Gain, Tram., 1907, 91, 1049.52 R. Oliveri-Tortorici, Abstr., 1900, i, 653ORGANIC CHEMISTRY-HOMOCYCLIC DIVISION. 121diazo-salts. The non-existence of aliphatic diazonium salts is alsoaccounted for.Perhaps a greater difficulty is presented by the metallic diazotates(diazo-oxides) and diazo-cyanides. Caio represents the normal orsyn-compounds as quinonoid, but having the hydroxyl, &c., attached tothe tervalent nitrogen atom (I) and the iso- or anti-compounds ashaving the ordinary azo-constitution (11) :This formulation has been but little discussed at present, but it ispointed out that it accords with the different behaviour of the twodiazotates towards phenols, the compound (11) having less tendency tocouple from its having already the azo-constitution, whereas onIIantzsch’s hypothesis the syn-compound might be expected to coupleless readily than the anti- on account of the pxjsibility of sterichindrance :The small number of coloured diazonium compounds hitherto knownhas been increased by the preparation of a remarkably stable seriesof yellow diazonium salts from benzoyl- 1 : 4-naphthylenediamine.53Their aqueous solutions are also yellow, thus differing from the simplerdiazonium iodides and thiocyanates, which yield colourless solutions,and mere regarded by Hantzsch as owing their colour in the solidstate to the presence of the isomeric syn-diazo-compound in solidsolution.The new salts form neutral solutions, couple readily withalkaline P-naphthol, and yield the nitrosoamine with weak alkalis,and hence can only be regarded as true diazonium compounds. Theauthors adopt Cain’s constitution, representing the salts as eitherpara- or ortho-quinonoid :An alternative quinonoid structure might be obtained by assuming63 G. T. Morgan and W. 0. Wootton, Tram., 1907, 91, 1311122 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.the presence of a labile hydrogen atom attached to the nitrogen of thebenzoylamino-group 54 and wandering to the diazonium nitrogen :In the examination of the diazonium compounds from benzene-sulphonylbenzidine and as-benzenes~lphonylmethylbenzidine,~~ it wasfound, however, that coloured diazonium halides were obtained fromboth compounds, although in the second case the labile hydrogen atomis replaced by methyl.The authors therefore adopt the formula :The nature of the transformation of s-trihalogen-substituteddiazonium salts of weak acids into quinonediazides 56 has been morefully elucidated by a study of the mixed chlorobromo-derivatives.57No difference is to be found in the behaviour of chlorine and bromine,so that in the conversion of the symmetrical 3-chloro-5-bromo-p-toluidine, for instance, into quinonediazides, chlorine and bromineare eliminated in equal proportions, the two ortho-positions beingequivalent.When halogen is also present in the para-position, thecomparison of different chlorobromo-derivatives shows that elimina-tion takes place from the two ortho-positions with equal frequency, andfrom the para-position with half that frequency, so that the ratioThe authors do not incline t o accept Gain's formulation of thediazo-compounds. They assume a benzenoid structure for the soliddiazonium salts, but consider that an aqueous solution contains o- andp-quinonoid phases in equilibrium, under such conditions that eachortho-phase occurs twice as often as the para-phase. No explanationof the constancy of this ratio is offered. The qiiinonoid compoundspresent in solution are represented as carbonium derivatives, so thatthe transformation in a particular case may be shown thus, only oneol the two ortho-configurations being given :o : o ' : p = 2 : 2 : 1 .54 J.T. Hewitt, Proc., 1907, 23, 181.55 G. T. Morgan and J. M. Hird, Trans., 1907, 91, 1505.56 Ann. Beport, 1905, 107.57 K. J. P. Orton and W. W. Reed, Trans., 1907, 91, 1554OEtGANIC CHEMISTRY-HOMOCYCLIC DIVISION. 123",*OHBrN2\//\BrfiBrBr OH-+--3Diazonium compounds of this type, although yielding almostexclusively quinonediazides when heated with dilute acids, readilyundergo the normal conversion into phenols under the influence ofsunlight.58 This is shown to be entirely a diazonium reaction, notdependent on the intermediate formation of a syn-diazohydroxide, asit takes place under conditions unfavourable to hydrolysis, as in95 per cent.sulphuric acid solution. Solutions of diazotates are verystable when exposed to light. When alcohols or acetic acid areemployed as the solvent instead of water, the corresponding ethers orphenyl acetates are obtained, the phenetole formation, for instance,being favoured by the exposure of a suspension of the diazonium saltin alcohol, free from acid, to sunlight.Among other investigations in the department of diazo-compoundsmay be mentioned a study 59 of the red oil found by Griess, togetherwith azobenzone, in the product of the action of potassium ferro-cyanide on diazobenzene chloride.Since it yields triphenylhydrazine,NPh,*NHPh, on reduction, and undergoes the semidine transformationto form aminotriphenylamine, NH,*C6H,*NPh,, it is regarded ashaving the constitution C H < NPh I * NPh' I n the case of the diazotoluenesalts, the reaction appears to be more complicated.By the diazotisation of aniline with 0.5 mol. of sodium nitrite indilute acetic acid solution, an orange isomeride of diazoaminobenzenebas been obtained 60 the constitution of which is represented by theformula, NEPh<rPh. Its acetic acid solution probably contains a Ncompound, NH,Ph<h. NPh OAc, which couples with P-naphthol in thecold, yielding a red colouring matter, whilst diazoaminobenzene onlycouples on boiling, and gives a yellow product.Cuprous chloride or58 K, J. P. Orton, J. E. Coates, and F. Bnrdett, Trans., 1907, 91, 35.69 A. Ehrenpreis, Abstr., 1907, i, 453. 6o E. I. Orloff, ibid., 365124 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.molecular copper decomposes the compound at the ordinary temperatureinto phenol, aniline, and nitrogen. The same isomeride is obtained inpresence of other organic acids, but the stronger the acid the lesstendency is there t o form the new compound.The absence of isomerism in the mixed aromatic diazoamino-com-pounds has frequently been investigated. Since in the usual methodof preparation from diazo-salts and amines a considerable part is playedby the water and electrolytes present, an attempt has been made 61 t orealise the isomerism by the synthesis of unsymmetrical diazoamino-compounds from azoimides and magnesium organic derivatives.Theattempt failed, however, the same product being obtained from phenyl-azoimide and magnesium a-naphthyl bromide, and from a-naphthylazo-imide and magnesium phenyl bromide. Several pairs of compoundswere examined in the same manner.Phenylmethyltriazen 62 bas been regarded as tautomeric in character,reacting in the two forms C,H,=N:N*NHMe andC6H,*NH*N: NMe,the second formula being an indirect inference From its behaviour withacids. Its discoverer has now shown63 that it and its homologuesareonly correctly represented by the first formula, as the condensation withdiazobenzene salts gives rise to bisdiazoamino-compounds which arealways symmetrical, having the constitution R*N:N*NR’*N:N*R”.This is proved by the fact that the product from phenylmethyltriazenand p-diazotoluene chloride is identical, and not isomeric, with thatf rom p-tolylmethyltriazen and diazobenzene chloride.An interesting prepnration of certain aminoazo-compounds, whichdiffers from those usually employed in being additive instead of sub-stitutive, consists in the interaction of the p-diazoimides and activeamines.G4 Aniline does not react i n this way, but satisfactory resultsare obtained with the naphthylamines and certain m-diamines. Sincemonoal kylnaphthylamines reac t, only less readily, whilst dialkylnaphthyl-smines do not react, the authors assume that the addition occursthrough the intermediate assumption by the amine of a quinonoidconfiguration :61 0.Dimroth, M. Eble, and W. Gruhl, Abstr., 1907, i, 664.63 0. Dimroth, M. Eble, and W. Gruhl, Zoc. cit.64 G. T. Morgan and F. M. G. Micldethwait, Trans., 1907, 91, 1512.Ann. Report, 1905, 107ORGANIC CHEMISTRY-HOMOCYCIiIC DIVISION. 125N:SO,Ph H.NHA /\/\1 1 + 1 1 1 -\/ \/\/ .. NS02Phi HALN HHS0,Ph*HHydraxones and Hyd~ox?lazo-compounds.The results of a spectroscopic study of the hydroxyazo-compoundsand their derivatives 65 have led to the conclusion that whilst the para-compounds and their hydrochlorides have the azo-constitution, the o-quinonehydrazone formula must be assigned to the ortho-compoundsand their acyl derivatives. The ethers and hydrochlorides of the ortho-series, on the other hand, show absorption spectra indicating that theyhave the azo-structure.The spectrum of the hydrochlorides suggeststhat they are carbonium salts.66 The hydroxyl or ethoxyl group havingsome residual affinity, its presence in the benzene nucleus of an azo-compound modifies the spectrum of azobenzene considerably, but whenthe residual aanity of the substituting group is diminished by replac-ing the hydroxylic hydrogen by acetyl or benzoyl, the spectrumapproaches more nearly to that of azobenzene.Spectroscopic evidence also goes to show 137 that the phenylhydrazonesand osazones exist in neutral solutions in the form of hydrazones, withthe exception of phenylglosalosazone and dextrosazone, which appeart o be partly or entirely in the azo-form.But when sodium ethoxide isadded to the solutions, a part a t least of the substance is convertedinto the azo-compound. The influence of the presence of neighbouringhydroxyl groups, and of the conjugation of :C:N* linkings, was alsostudied.The same problem has also been attacked by a number of workersfrom the chemical side. In favour of the azo-constitution for thepara-compounds is the conversion of p-benzoquinonebenzoyIphenylhyd~-azone (I) into benzoxyazobenzene (11) by contact with potassium65 W. B. Tuck, Trmw., 1907, 91, 449. 66 F. Baker, Gid., 1490.E. C. C. Baly, W. B. Tuck, E. G . Marsden, and M. Gazdar, ibid., 157%126 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.hydroxide in the cold, a transformation which is also undergone by thesubstituted derivatives : 68O:/=\: N*NPh*COPh COPh* O/--\N: NPh.\=/ \-/(1.) (11.1There is less agreement as to the ortho-compounds. Whilst Tuckconsiders these to be hydrazones, the whole of the o-hydroxyazo-com-pounds with their ethers and esters are regarded by Auwers 69 as re-taining the azo-structure. According to this author, the acetyl deriv-ative of benzeneazo-p-cresol is an O-derivative. On reduction, it yieldsthe N-acetyl derivative of the hydrazo-compound, but it is not possibleto obtain the quinonehydrazone on gentle oxidation with ferric chlorideor mercuric chloride, as it at once reassumes the azo-configuration :Me MeThe product of the action of as-benzoylphenylhydrazine on P-naphtha-quinone was found also tVo be an azo-compound, being identical withthat obtained by benzoylating P-benzeneazo-a-naphthol. It undergoesreduction to the hydrazo-compound.Auwers thus considers theseO-benzoyl- and acetyl-derivatives to undergo spontaneously the samechange as that observed by Willstatter and Veraguth in the para-seriesunder the influence of potassium hydroxide. Auwers’ paper is describedas a preliminary note, so that a further experimental investigation ofthis question may be expected.A transformation which is in a sense the reverse of that ofWillstiitter and Veraguth, namely, the isomeric change of azo-com-pounds into hydrazones, occurs on heating tria~ylmethanee,~O thecoloured compounds of the constitution Ac,C*N:NPh passing into thecolourless isomerides Ac,:N*NAc*Ph.The transfer of the labile grouphere is from carbon to nitrogen. One of the acyl groups in the tri-acylmethanes is evidently very loosely combined, When acetyl andbenzoyl are both present, it is the acetyl group that becomes labile.The absorption spectra in the visible region of a number of nitratedp-hydroxyazo-compounds have been examined with the view of studyingtheir constitution.71 The p-nitroazophenols and their salts exhibitabsorptions of radically different type. The authors regard the salts as08 R. Willstatter and H. Veraguth, dbstr., 1907, i, 453.69 K. Auwers, ibid., 554.70 0. Dimroth and M. Hartmann, ibid., 1090.71 J. T. Hemitt and H. V. Mitchell, Trans., 1907, 91, 1251ORGANIC CHEMISTRY-HOMOCYCLIC DIVISION.127being isonitro-derivatives, and they are thus represented as quinonoid.This is in accordance with the views of Baly and Tuck72 on thestructure of the p-nitrophenylhydrazones of aldehydes and ketones. Thequinonoid alkali salts have a purple or blue colour, the absorption beingshifted towards the red in comparison with that of the parent com-pound. The tabulated absorptions indicate that the oscillationfrequency is less the longer the chain of alternate double and singlelinkings in the molecule.As the formation of lakes is known to require the presence oftwo hydroxylic groups (one of which may be carboxyl) in the ortho-position relative to one another, this view of the constitution of thenitro-derivatives was tested by a comparison of the salts of two isomericcarboxylic acids derived from benzeneazo-a-naphthol.Both acids formblue potassium salts, but whereas the onecontaining OH and C0,H inthe ortho-position gives brown precipitates with salts of the heavymetals, thah in which NO2 and CO,H are in the ortho-position givesblue precipitates. The quinohoid structure is therefore intact in thelatter case, and the compounds are related thus :/-\ /-\(Blue. ) (Brown.)\=/(Blue. ) ( Blue. )The nitro-group has a considerable influence on the formation ofphenyl hydrazones. Thus, whils t o -nitrophenyl h y drazine reacts readilywith p-quinones and their monoximes, p-nitrophenylhydrazine onlyreacts readily with the monoximes, and the m-compound is oxidisedwithout forming a h y d r a ~ o n e .~ ~ It is possible that the o- and p-phenyl-hydrazine react in the tautomeric ittonitro-form, which mould be lessreadily oxidisable. Whilst there is little doubt that the derivativesfrom quinones are p-hydroxyazo-compounds, the monoxime derivativeshave different properties. The alternative formulae are :But in their resistance t o acids and in their behaviour on oxidation,72 Trans., 1906, 89, 982. v3 W. Borsche, Abstr., 1908, i, 66128 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.these compounds do not resemble phenylhy droxylamine derivatives,and they are therefore t o be regarded as hydrazones.As an appendix to the hydrazones, some experiments on the oxida-t.ion of aromatic hydrazines by atmospheric oxygen may be menti0ned.7~The main product is the parent hydrocarbon, according to theequation :but this is always accompanied by some hydrocarbon of the diphenylseries :R*NH*NH, + 0 = RH + N, + H,O,2R*NH*NH, + 0, = R*R + H, + ZN, + ZH,O.It is suggested that the first product is a hydroxyhydrazine, whichthen decomposes directly :R H RH k-k --+ NiNH*OH H 6Hor through the intermediate formation of R*N:NH, to which thetransient crimson coloration always observed during the progress ofthe oxidation may be due.The remarkable isomeric changes undergone by the arylhydroxjl-amines in contact with dilute sulphuric acid75 have been furtherinvestigated by Bamberger and his pupils,76 and considerable light hasbeen thrown on the transformation, although certain points stillremain obscure.m-Xylylhydroxylamine yields in this way iminoxylo-quinol, which readily loses ammonia to form xyloqainol. Whenalcohol and sulphuric acid are used, water being carefully excluded,the corresponding ethyl imino-ether is obtained, yielding the quinolether with water :Me OEt Me OEt\/ \//\ .+ II Il Me/\\.( \/NH*OH NH-+ l1111\6e0AMe \/But the change is not arrested at this point. A part of the sub-stance is transformed into ethers of xylorcinol and xylohydroquinone.It is the mechanism of this reaction that has been studied.Experimental evidence is produced t o show that quinols and theirethers exist in solution as hydrates or alcohoiates, and also that wateror alcohol may be added on at a *C:C- linking.The change of position74 F. D. Chattaway, Tmns., 1907, 91, 1323.75 E. Barnberger, Abstr., 1903, i, 83.A ~ s ~ T . , 1907, i, 616, 517, 518, 519, 520, 521ORGANIC CHEMISTRY-HOMOCYCLIC DIVISION. 129of OH and OEt may be then only apparent, being due to the additionand removal of water or alcohol at different points on the benzenerings, the only truly isomeric change being the wandering of themethyl group. This is explained as being similar to the pinacone-pinacolin change, which consists in an interchange of methyl andhydroxyl :Me Me,C--C<OH Me Me,C--C<OH -+ I 1 Me OH I I OH MeThe production of hydroquinone monoethyl ether and xylorcinoldiethyl ether from 9%-xyloquinol may then be represented by thefollowing scheme :Me OH\/OH.H/\HMe " OH f IIXMe OH OEtMe OHH/\HH O M e \ .. 0H,!,)Ne/\OH OEtOH OHA OH OEtMeOEV'\H -+ H(/MeOEtOHH O M eOEtMe/\HThe Terpene Group.The recent work on the terpene group includes several newsyntheses from the Manchester laboratories. Thus carvestrene, whichis of importance as occupying the same position in the m-cymene groupas dipentene does in the p-cymene series, and to which Baeyerassigned the constitutionCMeAH27 7H\/CH2H,C CH*CMe:CH,has now been synthesised 77 in a manner which fully confirms Baeyer'sconclusions. Starting with cyclohexanone-3-carboxylic acid (I) theethyl ester is caused to react with magnesium methyl iodide, and after'7 W. H. Perkin, jun., and G. Tattersall, Trans., 1907, 91, 480.REP.-VOL.IV. 130 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.hydrolysis and distillation under reduced pressure, the lactone (11) ofcis-1 -methyl-l-cycZohexanol-3-carboxylic acid is obtained :Me0H,/'\H,H,()H*C02Me\-0d ' H 2 I HI ,\/ IH-COBy the successive action of hydrobromic acid and pyricline, this is con-verted into the unsaturated 1-methyl-A1-cycZohexene-3-carboxylic acid(111), the ethyl ester of which reacts with magnesium mgthyl iodide toform a new alcohol, dihydrocarvestrenol or Al-m-menthenol (1V) :Me MeHe/\H H/\HH2 H2H:()H-CO,H H),,)H* CMe,*OH(111.) (IV.)This is the meta-analogue of terpineol, and readily yields carvestreneon digestion with potassium hydrogen sulphate. Other interestingproducts were obtained in the course of the research.The synthesis of terpin hydrate 78 has now been greatly ~irnplified,7~it being found that the treatnient of ethyl cyclohexanone-4-carboxylatewith magnesium methyl iodide, which formed the starting-point of theoriginal process, yields terpin directly under suitable conditions.Three of the products of the oxidation of pinene, namely, terebic,terpenylic, and homoterpenylic acids, have now been synthesised by asimple application of Grignard's reaction to ketonic esters.b0 Thusethyl acetosuccinate and magnesium methyl iodide yield ethylterebate :YOMe Me, ONgI CRIe,---,FH*CO,Et yH*CO,Et tH*CO,Et 0 'y 3 2 --++ YH2 QHz -+C0,Et C0,Et C O p - 1I n an exactly similar way, ethyl P-acetylglutarate is converted intoethyl terpenylate, and ethyl P-acetylndipate into ethyl homoterpenyl-ate.Other investigations in the terpene series have been very numerous,and in some cases highly controversial questions of priority occupy78 Ann.&port, 1904, 117.79 F. W. Kayand W. H. Perkin, jun., Trans., 1907, 91, 372.J. L. Simonseii, ibid., 184ORGANIC CHEMISTRY-HOMOCYCLIC DIVISION. 131a large space in the polemical discussions, a cause of which is thegreat variety of possible formulae for certain members of the series.A study of the reactions of terpinene nitrosite has led Wallachto the conclusion t h a t it must be represented by the structuralformulaCH, O*NO\/although he does not consider that the compound can be unimolecular,in spite of the results of molecular weight determinations.Thisaccords well with the formula (I) for terpinene suggested by its otherchemical reactions and on optical grounds : 82_ _.-, CHMe, CHMr1.1 (II.) (111. )although Wallach 83 does not exclude the possibility of (II), andassigns the formula (111) to P-terpinene.Synthetical phellandreae, from carvoment hene dibromide, resemblesthe natural hydrocarbon i n all respects except its optical activity andboiling point.64 It is represented by the formulac=2I3 CHMe,Dihydrophellandrene and dihydroterpinene are found 85 to beidentical with the carvomenthene obtained by reduction of limonenemonoh ydrochloride.A comparison of various naturally occurring camphenes with thesynthetical product has yielded evidence for the existence of twoisomeric camphenes.s6Nopinone (I), which has hitherto only been obtained in smallquantities, is readily prepared by the oxidation of nopic acid, which81 0.Wallach, Abslr., 1907, i, 228.83 Abstr., 1907, i, 943.84 I. L. Kondakoff and I. Schindelmeiser, ibid., 329.85 F. W. Semmler, Zoc. cit.82 F. W. Semmler, ibid., 714.b8 0. Wallach, Abstr., 1907, i, 1061.K 132 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ocours in the oxidation products of turpentine.87 When acted on withzinc and ethyl bromoacetate (compare p. 135) a hydroxy-ester is firstformed, which on heating with potassium hydrogen sulphate yields theunsaturated ester (11). On distillation, the acid loses carbon dioxideto form /I-pinene (III), the configuration of which, however, is notidentical with that of the natural hydrocarbon.ss0 CH* C02Et CH,H& I12(>H H2(>HH H H(1.) (11.) (111.)An attempt was made89 to synthesise nopinone by a series ofreactions terminating in the production of 4-/I-bromoisopropylcyclo-hexanone (IV), which is related to nopinone (I) in the same way asdihydrocarvone hydrobromide (V) is to carone (VI) :0 0 0H ) ! , H 2 HJ:p2(IV.1 (V. 1 (VI.but the ring failed to close under the action of alcoholic potash. Anattempt to cause the sodium derivative of ethyl 4-/I-bromoisopropyl-cyclohexanone-2-carboxylate (VII) to undergo internal condensationwith formation of ethyl nopinonecarboxylate (VIII) was0 0/\ HH CBrMe2(VII.) y111.)similrtrly unsuccessful, from which it appears that, in dicyclic systems,the cyclopropane ring is more readily produced than the cyclobutanering.57 0.Wallach and A. Blumann, Abslr., 1907, i, 936.88 0. Wallach, ibid., 1058.8" W. H. Perkin, jun., and J. L. Simonsen, Tyans,, 1907, 91, 1736ORGANIC CHEMISTRY-HOMOCYCLIC DIVISION. 133Much work has been done on the constitution of sabinene, to whichMeSemmler Q0 assigns the formula FI,~ Hog:, special attention havingC HMe,been given to the products obtained on breaking down the ring so asto obtain cycjopentene and cychpentadiene derivatives. Other inves-tigations have included teresantalic acid 91 and the di- and tri-cyclu-santalols.The method adopted for the synthesis of isolaurolene 93 has beenapplied to campholene.94 ad-Trimethyladipic anhydride yields tri-methylcyclopentanone, from which the tertiary alcohol is obtained withmagnesium methyl iodide, distillation then yielding campholene :YH,-C Me,--CO yH,-CMe, FH,--CMe,CH,* CHMe CO >' C€€,*CHMe>Co CH,*CHMe >CNe*OH(Campholene. )The degree of perfection which has been reached by the hypothesesof structural organic chemistry, and their great adaptability to theexperimental facts, are perhaps nowhere better illustrated than in thesynthetical study of the terpenes, but it has only been possible t omention a few of the very numerous researches in this department ofchemistry, and the closely allied group of the camphors must be leftuniiot iced.I n connexion with the study of natural products, reference shouldbe made to the very careful investigations of chaulmoogric acid 95 andhomoeriodictyol.9G The former is found to be a cyclopentene deriv-ative, and to react in accordance with both of the following formuh :CH/\ A*YH QH*LCH,],,*CO,H ~H-$l*[CH,],2*C0,RCH,*CH, CH,*CH, 9but as the acids obtained from the seeds of three botanically distinctspecies of plants are found to be identical, it is not possible to considerAbstr., 1907, i, 145, 714.91 F.W. Semmler and K. Bnrtelt, ibid., 703, 1062.92 F. W. Semmler and K. Bode, ibid., 431.93 Ann. Report, 1906, 141.94 G. Blaiic, Abstr., 1907, i, 1058.gr; M. Barrowcliff and F. B. Power, Trans., 1907, 91, 557.96 F. B. Power and F. Tiithi, ibicl., 887134 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.chaulmoogric acid as a mixture of stable isomerides, and tautomerismor dynamic isomerism between the two forms must be assumed.Theallied hydnocarpic acid has the same structure, differing only incontaining ten methylene groups in the side chain instead of twelve.Bin3 Syntheses ccnd Po Zycyclic Compounds.The conditions of stability of hydrocyclic compounds containingthree- or four-carbon atom rings have been discussed from variouspoints of view,g7 and it is found that the relative stability is dependentrather on the nature and position of the attached groups than on thenumber of atoms forming the ring. The reaction between tribromo-propane, CH2Br*CHBr*CH2Br, with ethyl sodiomalonate seemed tooffer an equal chance of formation of a cyclopropane or cyclobutanering, but the actual course of the reaction was unexpected, unsaturatedopen-chain compounds being exclusively obtained (see p.92).The series of hydrocyclic hydrocarbons has now been completed bythe preparation of cyclobutane by the reduction of cyclobutene withhydrogen and nickel,gs butane being obtained a t a higher temperature.The general chemical behaviour of cyclobutene indicates 99 that it is thesimplest dicyclic hydrocarbon,CH- CH,1 \ 1 9 CH,* UHand this constitution accords with its physical properties, and with theresults of the reduction of higher dicgclic hydrocsrbons (terpeoes) bySabatier and Senderens' method.The yellow modification of cinnamylidenemalonic acid, when heatedCHCHwith baryta, yields phenylcyclobutene, CHPh< I >CH,, and di-yHPh*QH*QH*QH2CHPh*CH*CH* CH,'phen yl tricy clooctaiie,The white modification of the acid, on the other hand, yields thelatter hydrocarbon together with diphenyldicyclohexane :yHPh*QH* C/H2CHPh.CH *C H,'Another new cyclobutane synthesis is the production, by the actionof sulphuric acid on ethyl s-dimethylacetonedicarboxylate, of the com-Seealso A. Kotz, Abstr., 1907, i, 1018.97 W. H. Perkin, jun., and J. L. Simonscn, Trans., 1907, 91, 816, 840.98 R. Willstiitter and J. Bruce, ibid., 1018.99 N. Zelinsky and J. Gutt, ibid., 1908, i, 14.0. Dobner and G. Schmidt, ibid., 1907, i, 204ORGANIC CHEMISTRY-HOMOCYCLIC DIVISION. 135pound, CMe<"->CMe*C02Et, which readily hydrolyses andloses carbon dioxide, yielding the hydroxyketone,C(0H)C M e < ~ ~ o ~ C H M e .2The method of synthesis of naphthylenediarnine derivatives describedon p. 135 of last year's Report may also be applied when the benzenederivative used has a side-chain of only two carbon atoms, providedthat a methyl group occupies the neighbouring position to the side-chain.3 Thus o-toluyl chloride and ethyl sodiocyanoacetate give ethylcyano-o-toluylacetate, C,H,Me*CO*CH(CN)*CO,Et, which on heatingwith ammonium acetate gives et h y 1 p-imino-a-cyano-p-o- tolyl-propionate. Acids then convert this into ethyl 1 : 3-naphthylene-diamine-2-carboxylate :1 : 4-Naphthylenediamine derivatives may be synthesised in a similarmanner :WalIach5 has described a new method of enlarging carbocyclicsystems.The cyclic ketones readily condense with esters of bromo-acetic acid to form hydroxy-esters, which after treatment withhydrogen bromide and reduction yield cyclylacetic acids. (Cyclyl issuggested as a general designation for univalent cyclic groups.) Fromthe amides of these acids the cyclylmethylamines are obtained byHofmann's reaction. The nitrites of the cyclylrnethylamines aredecomposed by acids, the first product being probably an unstablediazo-compound :G. Schroetcr and C. Stassen, Abstr., 1907, i, 532.E. F. J. Atkinson, H. Ingham, and J. F. Thorpe, Trans., 1907, 91, 578.J. F. Thorpe, +id., 1004. 5 Abstr., 1907, i, 602, 616136 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.On boiling, nitrogen is removed, and it may be supposed that adicyclic compound results with loss of water :CH,*CH,\ I l)CH>\CH,-CH’?CH,If, in the subsequent hydrolysis, the bond 1 is ruptured, an alcoholof the next higher cnrbocgclic system is obtained :(iH,*CH,*QH,CH2*CH2*CH*OH’and this is the principal reaction. If, however, rupture takes placeat the bonds 2 or 3, which are equivalent, a primary or secondaryalcohol is obtained, which may then lose water to form an unsaturatedhydrocarbon :,>C* CH,.7H2*C H FH,*CHCH,*CH, 2>C:CH2 Or CH,-CHSince the alcohols may be oxidised again to ketones, it is possible inthis way to prepare cyclohexanone from cyclopentanone, cyclooctanonefrom suberone, &c.Of the more complex hydrocarbons with condensed nuclei, aninvestigation of pyrenee has shown that only one of the rings isbenzenoid, the others being quinonoid in structure, the arrangement ofdouble linkings in pyrene and pyrenequinone thus being :cycZoHexanone and methyl alcohol undergo a condensation 7 withsulphuric acid resembling the formation of mesitylene from acetone,the product being dodecahydrotriphenylene (I), which yields tri-phenylene (11) on distillation with zinc dust :(1.) (11.)Attention has been called by Collies to the importance, in the8 J. N. Collie, Trans., 1907, 91, 1806. Compare J. N. Collie and E. R. Chrystall,G. Goldschmiedt, Abstr., 1907, i, 310. C. Mannich, ibid., 205.ibid., 1802ORGANIC CHEMISTRY-HOMOCYCLIC DIVISION. 137building up of rings, of the keten group, *CH,*CO. Compounds inwhich multiples of this group are present, of which ethyl acetoacetateand diacetylacetone are simple types, undergo condensation withremarkable readiness. Owing t o the labile character of the ketengroup, such compounds pass, under gentle treatment, with addition orloss of water or carbon dioxide, into the most diverse homocyclic andheterocyclic compounds. Numerous examples of ring-formation underthese conditions are adduced in illustration, and the importance ofcompounds of this type in the synthesis of substances occurringnaturally in plants is pointed out. Although the photo-syntheses ofthe plant have a t present no equivalent in the laboratory, it isevident that the study of these labile compounds, many of whichundergo condensation even at the ordinary temperature, in presence offeebly acid or alkaline solutions, without the aid of violent con-densing agents, may throw considerable light on obscure questions inplant-physiology.CECIL H. DESCH

ISSN:0365-6217    

DOI:10.1039/AR9070400109

出版商:RSC    

年代:1907

数据来源: RSC

摘要:

ORGANIC CHEMISTRY -HETEROCY CLIC DIVISION.IN reviewing the chemistry of heterocyclic compounds for the pastyear, the writer of this Report has been struck chiefly by the largeamount of attention given a t the present time to compounds occurringnaturally or forming essential portions of material obtained fromliving matter. Besides the important work which is at present beingcarried on with respect to the fats, the carbohydrates, the fate of theamino-acids1 in metabolic changes, and the general question of enzymeaction, amongst heterocyclic compounds we notice more particularlythe work on the fission products of the nucleic acids, which belong to thepyrimidine series, the pyrrole and indole compoiinds resulting fromthe hydrolysis of proteins, natural organic dye-stuff s, and more especiallythe alkaloids.Other matters of prime importance which are now engaging con-siderable attention are spacial questions as they affect the formationand stability of rings, and the relationships between the constitutionof cyclic compounds and their ability for salt formation, the latterquestion being intimately bound up with the connexion between coloiirand constitution, and, one may add, other optical properties such asmagnetic rotation.2Xpacia I Considwations.Baeyer’s strain hypothesis first gave a rational explanation of theobserved fact that rings of five or six members mere most easilyproduced, and when formed exhibited the greatest stability; it istherefore a matter of some interest to record observed cases whererings containing less than five or more than six atoms have beenproduced.A ring containing one atom each of carbon, nitrogen, and oxygen issupposed by Wieland to exist in the nitrile-oxides, the first of whichseries was obtained by Werner5 by removal of hydrogen chlorideF.Ehrlich, Abstr., 1907, ii, 44.Compare especially Sir W. H. Perkin, Trans., 1907, 91, 806.3 Ber., 1885, 18, 2277. Abstr., 1907, i, 527.l b i d . , 1894, i, 585ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. 139from benzhydroxamic chloride ; since these compounds show no greattendency to form additive products, Wieland replaces the generalformula :0Several four-membered heterocyclic compounds are described.M. Kohn 6 has eliminated hydrogen bromide from 8-bromo-p-methyl-amino-P-methylpentane hydrobromide and obtained a tertiarysaturated base, representing the change in the following manner :-+ (CH,),F--~*CH, (CH,),Q*NH*CH,CH2*CHBr *CH, CH,* CH*CH3The parent substance, trimethyleneimine, was described some yearsDiels and Stein ti regard the termolecular benzoyl cyanide describedback by Howard and Marckwald."C,H,*CO*N: $! *Y:N*CO*C,H,N:C*CO*C,H, ' by Nefg as possessing the structure:.I -but, on the other hand, W.Meister lo offers evidence against the ringstructure assigned by Dunstan and Goulding to methazonic acid,ll andconsiders that it has the open-chain constitution :OH*NO:CH*CH:N*OH.Blaise and Gaultll consider that the product obtained fromhydrazine and diketopimelic acid contains a seven-membered ring ;the writer would suggest that the substance may quite possibly be1 -aminodihydropyridine-2 : 6-dicarboxylic acid, and a similar criticismmay be applicable to the substance obtained by Ciusa13 by thereduction with sodium and amyl alcohol of the hydrazino-oxime fromcinnamylideneacetophenone.Leach l4 finds that pinene nitrosochloride reacts with twomolecules of potassium cyanate, giving a compound CI2HI7O3N3, towhich he assigns a cyclic structure involving an eight-memberedr i n g : v>NH.C=K-o-COC 7 H 4 ( C H , ) *NH* COThe formula is based on the fact that the subsbnnce exhibits thefeebly acidic properties usually associated with an imide, and whenreduced by zinc dust and acetic acid gives a very stable +-carbamide,Abstr., 1907, i, 338.Ibid., 1907, i, 528.lo Ibid., 1907, i, 885.l2 Absty., 1907, i, 280.l4 Trans., 1907, 91, 10.Ibid., 1899, i, 749.Ibid., 1896, i, 71.l1 TTans., 1900, 77, 1262.l3 Ibid., 62140 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.H-NH C7H14(CH3)=NH >CO, whilst cyanic acid is liberated as carbondioxiae and ammonia.Schroeter 15 in preparing benzenesulphonylanthranilic acid hasobserved a by-product insoluble in alkalis and evidently a bimolecularanhydride of the constitution :Whilst an eight-membered ring is involved in this case, Schroeterconsiders that the uoimolecuIar “acylanthranils” obtained in many casesduring the acylntion of nnthranilic acid are metoxazones of thetvDe : J JGabriel assumed l6 the intermediate formation of a nine-memberedring in the transformation of y-bromopropylphthalimide intoy-hydroxypropylphtbalimide, and, in carrying out corresponding reac-tions with /3-bromopropylphthalimide, Bartholdy l 7 has succeeded inactually isolating the corresponding compound :containing an eight-membered ring.Spallino’s 1* assumption that the internal anhydride, C1,HgO,N,obtained from phthalonic acid and anthranilic acid contains a nine-membered ring has some justification from the results of analyses andthe molecular weight determination.Bischoff and E. Frahlich l9 have examined the action of halogenisedncetylhalides on the sodium salts of dihydric phenols in the hope ofobtaining lactones of the formula :Whilst positive results were obtained in the case of cntechol,resorcinol and quinol did not give compounds of the desired type;although i t is possible that a two-fold polymerideis formed in the caseof resorcinol, such a compound would involve a fourteen-memberedring.When one comes to the question of actually realising any givencyclic formula, one needs to know the conditions under which ringl5 Abstr., 1907, i, 529.I7 lbid., 1907, i, 1043.l9 ]bid., 696, 697.l6 Jbid., 1905, i, 649.]bid., 872ORGANIC CHEMISTRY-HETEROCYCLIC DIVISlON 241closing is possible.There are evidently other factors at work besidesthose indicated in Baeyer’s original strain theory. Where a portionof the new cyclic structure is built up with two ortho-carbon atoms ofan aromatic nucleus, there is the possibility OF building a larger ringthan if one starts with two carbon atoms of aliphatic function.Thispoint is drawn attention to by J. v. Brdiin,20 who rinds that o-amino-phenylbutyric acid cannot be isolated in the free condition, but whenliberated from its salts passes immediately into an elactam, the ringhomologue of oxindol and hydrocar bostyril.Kaufler 21 introduces a somewhat novel conception in supposing that,where a substance contains two aromatic nuclei in its molecule, theseare frequently inclined towards one another, so bringing reactive groupsinto sufficient proximity to make ring formation possible. Thefollowing formulae :are assigned to benxidine, p-diaminostil bene,diamine respectively, and may account f u r thean azimide according to Vaubel and Schenerand 2 : 7-naphthylene-fact that the first gives22 and a unimolecularphthalglbenzidine,23 whilst a unimolecular phthalyl derivative maybe obtained from 2 : ?‘-naphthylenediamine, which is insoluble bothin acids and alkalis.Kaufler and Karrer also find that, when7-amino-2-naphthol is diaxotised, the diazonium salt couples withitself to a bimolecular compound, which is probablyBut special conditions may prevent ring formation by what isusually known as “steric hindrance,” and so Scholtz and Wasser-mann 24 in continvation of earlier work find that, whilst arylaminesand ae-dibromopentane usually give N-arylated piperidines, the sameresult cannot be obtained with o-toluidine or a-naphthylamine. Azo Abstr., 1907, i, 524.22 Ibid., 1906, i, 323.23 Koller, ibid., 1904, i, 778.Ibid., 307, 776, 794, 795, 799.Abstr., 1907, i, 339.The mol. wt.is unknown142 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.somewhat similar case of steric hindrance bas been observed byJiirgen~.~5Willstatter's researches on aniline- black have induced Bucherer 26 tobring all syntheses of indamines and azines by the oxidation of mono-or di-amines under one common point of view. A diamine (ortho orpara) is oxidised to a di-imide, and this will unite with a compound whichmay be represented by HR, giving a second diamine differing from thatoriginally employed by having one of its hydrogen atoms replacedby the group R. The process can then be repeated, and even thesynthesis of such a complex compound as safranine can be quiteeasily brought into the scheme.Methods for opening rings also deserve notice, and J.v. Braun27finds that, in addition to the treatment of benzoyl derivatives of cyclicsecondary amines with phosphorus pentahalides, cyanogen bromidefrequently gives satisfactory results, Thus the reagent unites withl-phenylpiperidine, giving phenyl-o-bromoamylcyanamide, which canafterwards be hydrolysed to the bromoamylaniline.The part played by the " keten " group, CH,*CO, in the synthesis ofa large number of compounds of entirely different series, some open-chain, some homocyclic, others heterocyclic, occurring in nature hasbeen discussed by Collie.28The application of heterocyclic structure to the compounds formedby many metals with amino-acids, Werner's co-ordination number beingemployed, is due in the first place to Ley,29 and has been enthusias-tically adopted by Ts~hugaeff.3~ I n this scheme, copper glycine isrepresented as (I) :80 fiCR,*CR,(I.1 (11.)and Tschugaeff extends the idea to certain compounds of cobalt, itsderivatives with the oximes of u-diketones (for example, nitroso-p-naphthol) being represented by the general formula (11). A matteraffecting heterocyclic compounds in general is discussed by B~-iihl,~lwho shows that, whilst the molecular refraction and dispersion ofsaturated heterocyclic compounds are normal (that is, correspond withthe values reckoned in the ordinary manner), the values obtained forunsaturated heterocyclic compounds point to optical depression.25 Abstr., 1907, i, 1036.27 Ibid., 960.'L8 Trans., 1907, 91, 1806.Ibid., 1907, i, 392, 830.2Q Ibid., 981.29 Abstr., 1905, i, 175.Compare ibid., 1900, i, 430.Trans., 1907, 91, 115ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION.143Onium ” Salts and Pseudo-bases.The relationships existing between cyclic ammonium, thiouium, andoxonium salts and the pseudo- (carbinol) bases obtained from them haveonce more attracted considerable attention. It is now a well-recognised fact that in those cases where the carbinol group (oroximido-group in case of azines) is in the para-position to a hydroxylor amino-group, water is removed with greater or less ease, in fact, inthe case of azines such removal of the elements of water isspontaneous, and the hydroxylated azonium salts are hydrolyticallydissociated.Thus whilst safranine and aposafranine salts are derived frompowerful bases, the corresponding hydroxylated azonium salts arecharacterised by extreme instability, and pass spontaneously on treat-ment with water by loss of acid into aposafranone or hydroxyapo-safranone.For aposafranone, two formulae have been proposed, thepara-quinonoid and the ortho-quinonoid :N Neither of which would correspond with the salt :N N/\CGH5 C1/\C,H5 C1The second formula representing aposafranone as an internal salt ofthe phenolic and quaternary ammonium functions is due t o Kehrmann,and is in many respects at variance with the properties exhibited bythe substance, for one would expect such a compound to add on theelements of water and give a strongly basic ammonium hydroxide.This, as we have seen, is not the case, any more than it is with thesimilarly constituted substances derived from dihydroxyphenylacridi’ne.An example in the latter series is given by A.E. Dunstan andMiss Cleaverley,32 who have obtained 2 : 8-dihydroxy-5-phenyl-3 : 7-di-methylacridine from the commercial dye-stuff, benzoflavinb, by heating32 Trms., 1907, 91, 1619144 ANNUAL kEPOltTS ON TBE PROGRESS OF CHEMISTRY.the base under pressure with diluted sulphuric acid. The hydroxylgroups were acetylated, methyl iodide then added, and the resultingquaternary ammonium salt hydrolysed. When alkali is added to asalt of the dihydroxyacridinium compound (I), a carbinol base doesnot separate (11), but in its place the corresponding anhydro-compound (111) :Considerations of this character make one somewhat critical asto whether the pyrines obtained by A.Michaelis, Rademacher, andSchmiedekampf 33 from bis-l-phenyl-3-methyl-5-pyrazolone are reallyto be represented structurally as the authors do by formula (I) andnot rather by formula (XI) :N*C,H5 N*C,H5 N*C6H, N*C,H5CH3*N/\C C/\N* CH, C H , * N A C : X X1:C'\C*CH3CH3*C-C--C--C*CH3 CH,*C= C-- C==C*CH3(1.) (11.1I l'x'l I I l'x(l I I I I IThey are obtained by acting on the corresponding bis-quaternaryammonium compounds with alkalis, hydrogen (or other) sulphide,primary bases, &c., so that X and X1, which may be the same, ordifferent, are either 0, 8, Se, NH, N*C,H,, &c.In fact, Michaelisand Hillmann34 themselves prefer the formula of an ammoniumhydroxide (I) to that of a bridged-ring compound (11) for the productof the, action of aniline on 4-chloro-2 : 6-lutidine methochloride :33 Abstr., 1907, i, 731. 34 Ibid., 726ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION, 145C6H3(IV.)although formula (111) is accepted for the product from aniline and5-chloroacridine methochloride when (IV) is available.Kehrmann 36 seems, however, prepared to admit the possibility ofpara-quinonoid structure in some cases. The condensation productfrom 6-amino-1 : 2-naphthaquinone and o-aminodiphenylamine differsso markedly from its isomerides in its properties that, in view of theisolation of 2 : 6-naphthaquinone by Willstatter and Parnas,37Kehrmann is quite inclined to admit the substance having theformula (I) instead of (11) :(111.)whilst formula (111) is suggested for the oxazine from 6-amino-1 : 2-naphthaquinone and o-aminophenol on account of its resemblanceto Meldola's blue.Ann. Report, 1906, 157.36 Abstr., 1907, i, 563.37 Ibid.? 425.REP.-VOL. 1V. r146 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Corresponding compounds are obtained with 6-hydroxy-1 : %naphtha-quinone ; the 7-hydroxyphenylisonaphthaphenazoniurn salts are orange-red, but the anhydro-base is dark blue, and the relationship can beexpressed by the formulae :It may be noted that a very similar constitution (derived from a1 : 7-naphthaquinone) was suggested in last year’s Report 38 for a darkblue anhydro-base derived from phenonaphthacridine.One of the most interesting contributions of the past year to theconstitution of oxonium salts is the work of A.G. Green and King 39on the halide salts of the quinonoid esters of phenol- and quinol-phthaleins. I n addition to the isolation of the free quinonoid mono-methyl ester of phenolphthalein from the hydrochloride mentioned inlast year’s Report,40 the new compounds derived from quinolphthalein,represented by formulae (I), (11), and (111), have been prepared andexamined :v6H4 CO,HCvGH4* CO,*CH,C(111. ) UV.1The free base corresponding to the second formula is represented bythe authors as possessing structure (IV), but from their paper it seemsdoubtful if it has been isolated, since whilst the chloride itself issoluble in water with an orangeared colour, it does not dissolve inaqueous alkalis, and if warmed with them hydrolyses, forming theoriginal lactoid monomethyl ether from which it was produced withmethyl alcohol and hydrogen chloride.58 Anic.&port, 1906, 172.40 Ann. Report, 1906, 179.39 Abstr., 1907, i, 933ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. 14’7Another very important paper on phenopyrylium compounds is dueto Decker and von Fellenberg,41 in which a large number of substances,the oxygen analogues of quaternayy quinolinium and acridiniurn com-pounds, are described. The coeroxonium and coerthionium compoundsare further studied,42 and the theory connected with the conjugatedouble linkings in application of Thiele’s theory undergoes furtherex tension.A few more papers on oxonium salts may be mentioned : Hantzschand Denstorff 43 and Feist 44 continue the discussion on the hydro-perbromides of negatively subst i t t i ted pyrones, whilst Faworsky 45 findsthat ethylene ether, O < ~ ~ ~ : ~ ~ ~ > O , readily forms oxonium salts.Finally, we may note that a cyclic, basic iodonium compound,I*OHdiphenyleneiodonium hydroxide, (\/\/\ has been prepared by I I I’\/-\/Mnscarelli46 by the action of moist silver oxide on di-iodoxy- or di-iodoso-diphenyl ; its acetate and oxalate are described.Pive-membered Rings.Amongst syntheses of pyrrole derivatives may be noted Clarkeand Lxpworth’s 47 production of Smith’s tetraphenylpyrrole 48 by theaction of heat on y-cyano-a-benzoyl-y-anilino-py-diphenylpropane,and the preparation of eeveral pyrroles of high molecular weightby J.Schmidt and R. Scha11,4Q who have employed aminodiphenylderivatives in conjunction with acetonylacetone. Ethyl phenacyl-acetate condenses readily with the three nitroanilines to give theesters of the 5-phenyl- l-nitrophenyl-3-methylpyrrole-3-carboxylic acids,Borsche and Titsingh 5O observing no steric hindrance even witho-nitroaniline, although it is incapable of giving piperazine derivativeswhen heated with ethylene dibromide and sodium acetate to 150’.Pyrrolidone, being now easily obtained by the electrolytic reduc-tion of succinimide,f~l bas been further studied by Tafel andWas~muth,5~ whilst the thiopyrrolidone, obtained from it by means ofphosphorus pentasulphide, is found by Tafel and Lawaczeck 53 to givea strong base on methylation, the methyl group becoming attached tothe sulphur atoms.Absts.., 1907, i, 950, 1064.AIL~L. Uepo~~t, 1906, 153.33 d b s l r . , 19.37, i, 283.45 Ibid., 274.dl Am., 949.4 Rd*) 1021.47 Trans., 1907, 91, 704.49 Abstr., 1907, i, 724.51 Abstr., 1900, i, 557.53 Ibid., 720.48 Ibid., 1890, 57, 646.50 Ibid., 1908, i, 103.p2 Ibid., 1907, i, 719.L 148 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Other pyrrolidone syntheses have been effected by H. Weber,54whilst Zelinsky and Schlesinger b5 have condensed acetonylacetone,ammonium chloride, and potassium cyanide to an amino-nitrile, which,when heated with hydrochloric acid, passes over into 2 : 5-dimethyl-pyrroline-5-carboxylic acid :CH,*C(CN)(NH,)*CH2*CH2*COoCH3 -+ CH==== I C(CHJ>NH,CH,*C(CH,)(CO,H)Markwalder 56 finds that methyl y-anilinopropyl ketone gives thehydrobromide of 1 -phenyl-2-methyl-4 : 5-dihydropyrrole when treatedwith hydrochloric acid, but on attempting to liberate the base theanilino-ketone is regenerated.I n addition to the synthesis by Emmert 57 of 1-phenyl-5-methyl-pyrrolidines by simultaneous electrolytic reduction of Isvulic acid andnitrobenzene, a general reaction discovered by L.J. Simon andConduche 58 is of interest, aldehydes readily condensing with ethyloxalacetate in presence of ammonia or primary arnines to give2 : 3-diketopyrrolidinecarboxylic esters := C,H,*OH + H,O + NH,R C,H,*O,C-YOCH, .GO, *C,H, + + RWHOSeveral interesting reactions of pyrrole and its derivatives havebeen studied, Pictet and Rilliet 59 finding that pyrrole and formaldehyde yield under suitable conditions a solid product, Cl,H1,ON,,which, when distilled, gives some a-methylpyrrole, but on distillationwith zinc dust furnishes a-picoline.Further, when methylene chlorideis heated to 120--130° with potassium pyrrole, two dipyridylmethanesare produced, one, melting at 11 2 O , is evidently linked by the nitrogenatoms, as it will not react with potassium, whilst the other, melting a t66", is probably a transformation product of the first compound andlinked by carbon in the a-position, as it reacts vigorously with potass-ium.The hope that either of these might furnish pyridylpyrrole onpassage through a red-hot tube and 80 lead to another synthesis ofnicotine was not realised.Pyrrole compounds, in which the hydrogen of the imino-group isreplaced by hydroxyl or an amino-group, behave frequently in aninteresting manner. Angeli and Marchetti 60 consider that the54 Abstr., 1900, i, 1071.56 Ibid., 1907, i, 639.58 Ibid., 963.Go Ibid., 1907, i, 436.55 Ibid., 720.57 Ibid., 339.59 Ibid., 445ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. 149nitroso-derivative they have obtained from 1-hydroxy-2 : 5-dimethylpyrrole probably possesses the second of the two formulie :C( CH,):QH C( C H3) : YHHoN<C(CH,):C*NO o:N'C(CH3)*C:NOHfor, when bydrolysed in presence of hydroxylamine, it yields the tri-oxime of hexane-2 : 3 : 5-trione,CH,*C(:NOH)*C(:NOH)*CH,*C(:NOH)*CH,.Bulow and KlemannGf have examined the action of nitrous acidon amino-compounds in a number of cases, and find that, whilstthe amino-group is diazotised when attached to carbon, be the com-pound carbocyclic or heterocyclic, amino-groups attached to nitrogenin a ring are removed in the form of nitrous oxide :>N*NH, + HNO, = H20 + N20 + >NH.The reaction is of considerable importance, as we shall see in thecase of the N-aminotriazoles.The occurrence of pyrrole groupings in various proteins is now wellrecognised, and papers on chlorophyll have appeared by Koiniewskiand Marchlewski,62 and Willstatter, in con junction with H~cheder,~,and Mieg.64 Willstitter and Hocheder have isolated and characterisedseveral hydrolytic products f rpm chlorophyll, most of which containnitrogen ; they also isolated phytol, C,,H,,O, a thick, oily, unsaturatedprimary alcohol boiling at 1 4 5 O under a pressure of 0*03-0.04 mm.Kuster 65 has oxidised the '( acid )' and " basic '' hsmopyrroles, andfinds that both of them give methyl ethylmaleinimide on oxidation.The haemopyrrole of weak acid function is the one most easily,oxidised, and it is probably 3-methyl-4-ethylpyrrole, whilst the otherI' basic " haemopyrrole is either 3-methyl-4-ethylpyrroline or perhaps2 : 4-dimethyl-3-ethylpyrroline, one of the methyl groups being lost inthe oxidation.Carrasco and Padoa66 find that 1-methylindole may be producedfrom dimethyl-o-toluidine by passing it over reduced nickel at 300° to330°, whilst the following syntheses lead to isatin and its derivatives.Rudolf BauerG7 finds that if oxanilide be treated with phosphoruspentachloride, diphen yloxalimino-chloride is formed, whieh ifheated on the water-bath and poured into water furnishes isatin :N N/\A + 2H20 = C6H5*NH2 + 2HCI + 1' /\/\CCl\ h / C * O H .I I ' C1.C N*C6H,COAbstr., 1908, i, 54.(13 Ibid., 784.65 Ibid., 572.]bid., 603,G2 Ibid., 1907, i, 866.tx Ibid., 865.Ibid., 1521-50 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The reaction, discovered by P.J. MeyerjGS of producing p-tolly-p-methylimesatin by the action of dichloroacetic acid on p-toluidinebas been examined by Ostromisslensky.~~ I n trying the reaction withaniline, Hellerr0 obtained a substance to which he assigned theconstitution of a disminostilbenedicarboxylic acid, but the presentauthor finds that a portion of the reaction product (about 24 per cent.)does consist of phenylimesatin.W.Peters 71 finds that many of the metallic derivatives of isatinare nitrogen derivatives, and the sodium oxygen salt could not beisolated, and Deussen, G . Heller, and Notze172 have followed thegradual change of sodium N-isatin to sodium isatate, and of the latterback to isatin under the influence of hydrochloric acid by conduc-tivity determinations.Heller73 has further followed the colour changes of these com-pounds, and observes that sodium N-isatin dissolves in water with thosame violet-red shade that isatin gives at first in dilute alkali; thechange to yellow is due to the formation of sodium isatate, but theaci-isatin salt is probably formed intermediately ; the silver derivativecertainly behaves as an oxygen salt and gives an O-ether74 withmethyl iodide, whilst the sodium derivative furnishes N-methyl-isatin.This O-ether is very reactive, giving a stable dianil with aiiiline anda-isatinphenyl hydrazone with phenylhydrazine, the latter beingidentical with Baeyer’s ben~eneazoindoxyl.~~ The latter substance byreduction and subsequent oxidation passes into indigo.Condensation products of isatin have been studied by C.Liebermannand R.Krauss76 and C. H a ~ l i n g e r . ~ ~ I n the former papers, theindigo-like colouring matters, of which indophenine, pyrrole-blue, andisatin-blue may be taken as typical, are submitted to a lengthyexamination, and in some cases provisional formuls are assigned ; threesuch formuls may be given here :CH:CHN d I6870727475171 >NHCH:CHDichloropyrrole-blue B.Ber., 1883, 16, 925, 926, 2261.Abstr., 1904, i, 730.lbid., 442. 73 ]bid., 442.Baeyer and Oeconomides, Abstr., 1883, 201.Abstr., 1884, 74.Ibid., 975.B i d . , 1907, 40, 4972.71 Ibid., 1907, i, 239.76 Ibid., 1907, i, 657ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. 151&HBlue from i~atindipiperidide.~~C. Liebermann and Danaila 79 have also oxidised the phenolisatins,whilst Haslinger has examined the action of ethylamine on isatin andits derivatives.He finds that three classes of derivatives may beproduced, of which the following may be taken as typical :N N'C,€€,, NC , H , ~ C * O H c H /\GO C,H,Br20C*NH*C2H,.c:o 4v C : N*C2H, C:( N H*C,H,),Yellow. Colourless. Green.An indole derivative whicb has aroused considerable interest in thelast few years is tryptophan, a product of the hydrolysisof manyproteins. Neuberg and Popowsky80 have worked out a method forobtaining the substance from fibrin, and prepared and analysed severalcoloured halogen derivatives, whilst A bderhalden and Kempe haveprepared several polypeptides from tryptophan, incidentally discoveringthat the violet coloration with bromine or chlorine water is peculiar t otryptophan itself, since the reaction is not given by its polypeptidesuntil after pancreatic digestion,Finally, the synthesis of racemic tryptophan has been effected byEllinger and Flamand.82 Indole-aldehyde and benzoylglycine condenseto an azlactone, which hydrolyses to a-benzoylaminoindolylacrylicacid.The latter compound by reduction and hydrolysis givestryptophan :78 Schotten, Abstr., 1891, 928, 1491.79 Abstr., 1907, i, 976.81 Ibid., 652.80 Ibid., 263.g2 lbid., 727152 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.C*CHO NC*CH2* CH (NH,) C0,HC8H6N* CH:C( C0,H) * NH*CO* C,H, -+ G x > H .NHM. Freund and Wirsing 83 have described di-p-dimethylamino-indigotin; they start with p-arninodimethyianiline, convert this into di-methylaminophenylglycine, fuse with sodamide, dissolve the productin water, and oxidise.The substance is easily soluble in organicsolvents with a green colour, and dyes wool a light green shade froman acetic acid solution. The solution in hydrochloric and sulphuricacids is blue, but will not dye wool.A. G. Perkin and Bloxam 84 have investigated the constituents ofnatural indigo, and find that indigo-brown contains at least threeconstituents, to which the formuh Cl6HI1O3N2, C16H1404N2, andC2,H2,0,N, are assigned. They are probably complex indoxylderivatives, since they yield anthranilic acid when digested with 50per cent. potash solution. Besides these substances, A. G. Perkin hasisolated a rhamnoside of kaernpfe1-01,~~ (r27H3001r, from the indigo ofIndigofeva arrecta, but it is improbable that the kaempferol is identicalwith the ( { Indigo-yellow " obtained by Bolley and Crinsoz 86 fromBengal indigo.A.Q. Perkin and Bloxams7 have so improved the method ofisolating indican, Cl4Hl7O6N,3 H20, from indigo leaves by extractionwith acetone that they can obtain more than 30 grams per kilo.Dextrose is obtained by hydrolysis, but by carrying out t h i s operationwith hot dilute sulphuric acid the indoxyl is converted into a brownsubstance ; nevertheless, its estimation has been effected by conversioninto indirubin by isatin. This is the basis of a quantitative processfor indoxyl devised by Orchardson, Wood, and Blosam.88Closely connected with indigo is the sulphur analogue, thio-indigo, which is obtained from carboxyphenylthioglycollic acid.P.Friedlander and Chwala describe methods for obtaining arylthio-glycollic acids ; 89 it may be noted that the amino-compounds are not83 Abstr., 1907, i, 254.85 Ibid., 435.87 Trans., 1907, 91, 1715.b Abstr., 1907, i. 525.tu Trms., 1907, 91, 279.86 Jahresb., 1866, 573.88 Abstr., 1907, ii, 203ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. 153obtained from the nitro-derivatives by reduction, since ring formationoccurs :SThe so-called thionaphthen derivatives form the subject of anThionaphtben, C,H,<-s->CH, has been described by Gattermannand Lockhart and by Komppa; it shows the grea ost analogy toimportant paper by F r i e d l a ~ d e r .~ ~OHnaphthalene. The hydroxylic derivative, C,H,<-s>CH, C W ) re-sembles a-naphthol in odour ; it is volatile with steam, and the methylethers of the two substances smell alike and have nearly the sameboiling point. The O-carboxylic acids are equally unstable, and theamderivatives have the same shade. Similar resemblances areobserved for the amino-compounds.Two methods for passing from anthranilic acid to cnrboxyphenyl-thioglycollic acid can be represented by the following scheme :/\NH, '\N2C1 (KCu[CNS]z) (NdzS) OSH 1 b02H --+ QO,H \/ I /CO,H -+ I )CO,H -.-+ \ \/ $1m "1 w_(Heat) /\S*CH,* C0,H -+ I ICO,H \/When the carboxyphenylthioglycollic acid is heated with sodiumhydroxide t o 150-160°, it passes into sodium hydroxythionaphthen-carboxylate (analogue of indoxylcarboxylic acid), the aqueous solutionof which is readily oxidised to thioindigo :From o-aminothiophonol, o-cyanophenylthioglycollic acid may beprepared, which ivomerises when warmed with dilute alkali to amino-thionaphthencarboxylic acid ; from the latter compound, carbondioxide may be removed by boiling with water, and the analogue ofa-naphthylamine produced.Abstr., 1907, i, 334154 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Kespecting indigo and thioindigo, Falk and Nelson 91 speculate onthe stereochemistry of these substances, and think it likely that,whilst indigo is a &-compound, its diacetyl derivative as well as thio-indigo belongs to the trans-series.Other work on complex derivatives containing the pyrrole nucleusmay be briefly mentioned, new carbazole derivatives having been pre-pared by Borsche and F e i ~ e , ~ ~ J.Schmidt and R. S~ha11,~3 and G.Schultz and H a ~ e n s t e i n , ~ ~ whilst Fichter and Probst have continuedthe work on quindoline derivative^.^^Pyraxoles and Iminaxoles.Pyrazole derivatives have been prepared by Biilow and D e s ~ n i s s , ~ ~St0ermer,~7 Franz Bachs and A l ~ l e b e n , ~ ~ A. Michaelis with Mielecke,99and Klopstock,l whilst the formation of ethyl l-phenylpyrazole-3-itcetate-4-carboxylate and ethyl l-phenylpyrazole-4-carboxylate ob-served by W. Wislicenus and Breit2 in the condensation of ethylformylglutaconate with phenylhydrazine is notable in that the pro-duction of the latter ester involves the scission of ethyl acetate (assuch) from the molecule.Pellizzari and Roncagliolo have examined the condensation productsof aminocarb~carbazide,~ NH,*CO-NH*N H*CO*NH*NH,, finding thatit loses ammonia on heating, giving urazine (see triazoles), whilst itcondenses as a primary hydrazine with acetylacetone to give a derii-ative of dimethylpyrazole.Ethyl ethoxymethylenemalonate has beenemployed by A. Michaelis and Remy in the synthesis of pyrazolones ;A. R. Smith and J. F. Thorpe obtain 4-cyano-l-phenyl-3-benzyl-4-ethylpyrazolone from phenylhydrazine and the ethyl derivatives ofethyl a-cyano-y-phenylacetoacetate,6 and Ruhemann 7 has preparedmonornet h p 1 1 -phen yl- 5 -p yrazolonedicarboxy late, starting with themethyl dicarboxyaconitate of Anschutz.Pyrazolonimines have been prepared by Moureu and Lazennec,* whocondense acetylenic or P-ketonic nitriles 9 with hydrazines ; where thelatter reagents are replaced by hydroxylamine, iaooxazolones result.I n addition to other pgrazolone syntheses by Michaelislo and Schenk,ll91 Abslr., 1908, i, 107.93 Ibid., 792.96 Ibid., 977.97 Ibid., 252.99 Ibid., 1908, i, 61.Ibid., 967.Ibid., 1905, i, 576.Trans., 1907, 91, 1891.8 Abstr., 1907, i, 159.l o Ibid., 716.92 Ibid., 1907, i, 242.94 ]bid., 1074.96 Ibid., 252.98 Ibid., 356.ZbicE., 1907, i, 735.Ibid., 833.Ibid., 1907, i, 445.7 I b i d ., 1359.Ibid., 397.l1 Ibid., 966ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. 155Stoermer and Johannsen,l2 Biilow,13 and Michaelis,l4 the paper byStoermer and Martinsen 15 is worthy of attention.on the conversion of pyrazolones into pyrazoles by phosphorus tri-bromide has shown that deoxybenzoin is reduced to stilbene andcarbostyril to quinoline by the same reagent, and the present worktends to show that the reaction is due to the replacement of hydroxylby bromine and reaction of the bromine atoms so introduced withhydrogen bromide and excess of phosphorus tribromide.A synthesis in the related indazole group is given by Freundler,lrwho acts on benzene-2-azobenzoic acid successively with phosphorustrichloride and water.Previous workbut the way in which he explains the mechanism of the reaction isdisputed by Tiff eneau.lsWindaus 19 has continued his study of the action of ammoniacal zinchydroxide solution on sugars, and a?-glucose, d-mannose, &fructose,d-sorbose, Larabinose, and Z-xylose have all been found to act in muchthe same way as glucose, whilst maltose and lactose give smaller yieldsof a glyoxaline.Rhamnose gives 2 : 4-dimethylglyoxaline in additionto 4-methylglyoxaline, showing that it furnishes acetaldehyde as wellas methylglyoxal and formaldehyde on decomposition.The formulation of histidine as iminazolylalanine is confirmed byWindaus and Vogt,20 who find that by elimination of the amino-group it is converted into a product identical with a synthesisedglyoxaline-4-propionic acid, the latter compound furnishing 4-/3-amino-ethylglyoxaline when the carboxyl is replaced by the amino-group ;Knoop 21 gives a further confir mation of the assigned structure bydegradation to glyoxaline.H.Biltz 92 finds that diphenylglyoxaline is oxidised by potassiumpermanganate to dibenzoylcarbamide, whilst Bonn 23 has effected asynthesis of benzylmethylglyoxaline, using benzylacetoacetic ester as astarting point.Amongst keto-derivatives of iminazole, the base prepared by Finger24by the interaction of acetiminoethyl ether and glycine ethyl ester,l2 Abstr., 1907, i, 966.l4 Ibid., 246.' 6 Ibid., 1904, i, 181.2o Ibid., 978.2.3 lbid., 646.Ibid., 986.l5 Zbid., 446.I7 Ibid., 1907, i, 158.l9 Abslr., 1907, i, 288.21 Iblbid., 788.2y Ibid., 1908, i, 55.BzJ2. SOC. chim., 1907, [iv], 1, 1201.lbid., 1907, i, 876156 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.is peculiar, inasmuch as it reacts with two molecules of benzaldehyde,the methyl as well as the methylene group taking part in thereaction.H, Biltz has studied the glyoxalones obtained by the condensation ofbenzoin with ~ a r b a m i d e , ~ ~ and also the acetylenediureine,26 firstobtained by S ~ h i f f , ~ ~ from glyoxal and carbamide.This substance, aswell as derivatives which have been described by seem>COYN H ~ ~ R ~ N HNH*CR*NH undoubtedly to possess the constitution, CO<originally assigned to them.Dieckmann and Kammerer z9 have obtained derivatives of thenearly allied parabanic acid in examining the action of hydrocyanicacid in phenylthiocarbimide, and of ethyl oxalate on phenylcarb-amide.0. Fischer3O thinks that theexplanation of the second Z-methylnaphth-iminazole obtained by Meldola, Eyre, and Lane 31 is given in that thesupposed molecule of water of crystallisation is really an oxygen atomwhich has not been removed during the reduction.This would makethe compound possess the constitution :Franzen describes the production of N-diaminonaphthiminazolefrom 2 : 3-naphthalenedihydra~ine,~~ and his observation of theformation of 2-phenylbenziminazole by warming benzaldehyde-o-aminoyhenylhydrazone with dilute mineral acids,33calls to mind the indole syntheses of Emil Fischer.Kym34 and Brand.S50 ther papers on benziminazole derivatives have appeared from25 Abstr., 1908, i, 56.27 Bid., 1878, 287.29 Ibid., 1907, i, 979.Ibid., 352.Trans., 1903, 83, 1185.Jbid., 321. 34 Ibid., 560.26 Ibid., 62.28 Ibid., 1890, 1290.32 Abstr., 1907, i, 880.35 I b i d . , 800ORGANIC CHEMISTRY -HETEROCY CLIC DIVISION. 1571 : 2 : 3-Triazoles have been obtained by Peratoner and Azzarello 313and Tamburello and Milazzo37 by tohe action of diazomethane and itshomologues on cyanogen and its chloride. The reactions are of the ~ ..N:YHN H < ~ : ~ * ~ ~ (or CI>’ and if typa CH2N2 + C2N2 (or CNC1) =suitable precautions are not taken the diazo-hydrocarbon reactsfurther, alkylating the imino-group.2-Substituted benzotriazoles have been obtained by Grandmouginand Guisan 38 by the reduction of o-nitroazo-compounds,Nand the azimidols, producedNby the action of alkali on o-nitro-sub-stituted phenylhydrazines, have been examined by Curtius and hisp ~ p i l s .3 ~ The first member of this series, benzazimidol,was described by Nietzki and Brauns~hweig.~OThe vexed question of the constitution of the products obtainedby the transformation of ethyl diazoacetate seems to be finallysettled by the work of Curtius, Darapsky, and Ernst MUller.*1 Bulowfirst pointed out the great probability of the so-called “dihydro-tetrazine” being N-sminotriazole, and this is definitely confirmed by theabove-named authors, who also show that the bisdiazomethane ofHantzsch and Silberrad is really C-aminotriazole, and that thetrue tetrazine series is represented by the so-called “ bisazoxy ”-com-pounds of Hantzsch and Lebmann.The relationships of the differentcompounds are well shown by a chart given in the second paper quotedabove, and the names in brackets are those by which the compoundshave been known at various times :36 Abstr., 1907, i, 979.a* Ibid., 1092.4o I t i d . , 1895, i, 135.37 Ibid. , 1088.3y Ibid., 969, 1078.41 Ibid., 1907, i, 262, 359, 450, 451158 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.#>CH*CO;C,H,Ethyl ciiazoacetate.$NaOH)N-- N>C*CO,HCO,H*C<~~~>C.CO,H 3 C02H*C< NH-NHRisdiazoacetic acid. - ~ - I Tetrazinedicarboxylic acid.RONH,Tetrazine. iV- Aminotriazoledicarb-(Bisazoxymethane. ) oxylic acid.(Dihydrotetrazinedi -carboxylic acid.) +p 2 0 )N-N+(HzS) i j (o)I I (Heat)(Heat) H i C H f-I (Bisazoxyacetic acid.) I (Heat)#--V CO,H* C C *CO,HJ.HC<$;>CH \/fl-3 NH,*C C*CO,HN H\/C- Aminotriazolecarb-oxylic acid.(Tris- bisdiazome thane-tetracarboxylic acid )$(Heat)M--R\/NH,*C CHNHC- Aminotriazole.(Bisdiazomethane. fJ(HN02) M-”v *HC 8 HNHTriazole.M. Busch42 draws attention to the fact that he had recognised theso-called diphenylurazine as N-phen ylaminotriazole some years back,43and Pellizzari and Repetto44 now think it quite probable that thebase, C,N6H6, obtained by Pellizzari and Cantoni 45 by the action ofcysnogen bromide on aqueous hydrazine is not ‘‘ guanazine,” but4-aminonuanazole :Stoll6 has similarly recognised the supposed dihydrotetrazinesobtained by the action of primary hydrazines on dibenzoylhydrazidedichloride as N-arylaminotriazoles : 4GAbstr., 1907, i, 564.43 Ibid., 1901, i, 616.46 Ibid., 1907, i, 359, 654.u Ibid., 1908, i, 65.45 Ibid., 1905, i, 577ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. 159The thiourets obtained by Fromm and Schneider 47 by oxidising thearyldithiobiurets with iodine :7-Y\/C,H,*NH*CS*NH*CS*NH, + I, = HI + CGH5*N:C C:NH,H1,NHhave been used by Fromm and Vetter 48 in the synthesis of triazoles andother ring compounds. Half the sulphur is eliminated by the actionof aromatic amines, open-chain compounds possessing the constitutionsC,H, *N: C( SH) *NH*C(: NH) * NH C,H,andrespectively being produced by the action of aniline and phenyl-hydrazine.The acetyl derivative of the first condensation product loses wateron boiling with alcohol and potash, and the resulting compound isformed according to the equation :CGH, N : C( SH) NH C( : NH) N H*NH* C6H,,VO*CH, VO*CH,BH YH C,H,*TH r;JHC,H,*N:C C:N*C,H, Or ( s:c c:N*c6H5) =\/NH\/NHThe compound produced from phenylhydrazine loses hydrogensulphide on heating, giving 3-amino-5-anilino-1 -phenyltriazole.Fromm and von Goncz 49 publish a further triazole synthesis,potassium cyanoiminodithiocarbonate, (KS},C:N.CN, being used asinitial material ; it may be converted into the corresponding dibenzylester, which then condenses with phenylhydrazine giving 5 (or 3)-amino-3(or 6)-thiobenzyl- 1 -phenyltriazole.An interesting study OF dynamic isomerism has been made byAcree5O in the case of phenylurazole and its 4-methyl derivative.Several tautomeric formulae are possible ; the substance behaves, how-ever, as if it had the structure (I) :(1.) (11.)47 Abstr., 1906, i, 714.4L) Ibid., 872.Ibid., 1907, i, 982.50 Ibid., 258, 796160 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.for the dissociation constants of the 2 : 3- and 4 : 5-amido-groups areK = 0.00001 and K=0.0000005 respectively, a result which is con-firmed by the conversion of the substance into a dimethyl ether ofstructure (11) by the action of diazomethane.Fetraxoles.Dimroth and Merzbacher 51 find that tetrazoles are producedby the interaction of arylazoimides and the phenylhydrazones ofaldehydes :and Wieland and Bsuer52 incidentally touch on the tetrazole andtetrazine groups in studying the action of alkalis on dihydroxy-guanidine.The reaction gives an ' I aminoazaurolic acid,"ON*C(NH,):N*NH*C(NH2):N*OH,the name calling to mind the " azaurolic acids " [for example,CH,*C(NO):N*NH*C( :N*OH)*CH,]obtained by Victor Meyer as reduction products of nitrolic acids.The aminoazaurolic acid yields isonitrosoaminodihydrotetrazinewhen boiled with 18 per cent. hydrochloric acid, and undergoes partialhydrolysis on reduction, hydrazodicarboxylamideoxime,NH,*CO.NH*NH*C(NH,):NOH,being produced. By the action of nitrous acid, a cyclic compound isformed, constituted probably as :When tetrazole itself is treated with benzoyl chloride in pyridinesolution, it undergoes fission, nitrogen is eliminated, and dibenzoyl-carbamide produced.Heller 53 further finds that, although no actiontakes place in the cold, when tetrazole and benzoyl chloride arewarmed, dibenzoylhydrazine is formed ; the same compound being alsoobtained from 1 : 2 : 4-triazole.Furan a d Erurazan.Very few syntheses are to be noted in this group, Ludwig5* hasobtained dialkyldihydrobenzof urans by the action of the Grignardreagent on phthalide; Fromherz and Meigen 55 have prepared andexamined the s p - and anti-oximes of methylfurfuraldehyde, whilst51 Abstr., 1907, i, 659.54 Ibid., 702.52 Ibid., 491.55 Iblbid., 232.53 Ibid., 261ORGANIC CHEMISTRY-HETEROCY CLlC DIVISION. 161diphenylene oxide (and carbazole) have been condensed with phthalicanhydride by Stummer.5Gvon Kostanecki and Lampe 57 find that reduction effects a fission ofthe furan ring in the tetramethyl ether of catechin, a reactioncorresponding with Alexander's 58 production of coumaran and o-ethyl-phenol by the reduction of coumarone with sodium and alcohol.Thet w o authors named have further examined the halogen substitutionproducts of the tetramethyl ether 59 and, con jointly with M a r s ~ h a l k , ~ ~synthesised some compounds which must be nearly related tocatechin,Tannin has formed the subject of further discussion, Nierenstein 6lconsidering that, as its acetyl derivative only contains five acyl groups,Dekker's formula,@ which corresponds with the possibility of a hepta-acetyl compound, cannot be coxrect.The hydrogenisation of the furan nucleus has been effected byPadoa and PontiF3 who passed furfuraldehyde vapour mixed withhydrogen over reduced nickel a t 2 2 5 O .The course of the reduction isillustrated by the following scheme :-+ EH-SH -+ C H C*CH, -+ gH-GH CH C*CH,*OH GH-GHv C H C*CHO v 0\/0 0CH2*YH, -+ CH2*FH2 I yH2'p% -+ I CH, CH*CH, CR, CH-CH, CH,C*CH, -\/ / //0 HO 0The methylfuran and secondary amyl alcohol were detected, thefury1 alcohol and methyltetrahydrofuran isolated and analysed, whilstthe methyl propyl ketone was separated as its semicarbazone.The furazan compounds may be mentioned here ; 64 Wielandsuggested some time back that the glyoxime peroxides, which havegenerally been represented as possessing structure (I), are moreprobably furazan oxides (XI) :R*;C;--8*R'b-o"I(1.)Quite recently,Gj he has56 Ahstr., 1907, i, 723.Ibid., 1908, i, 86.Ann.Report, 1906, 167.65 Zbid., 1908, i, 108.REP.-VOL. IV.\/0(111.)come to the conclusion that formula (111) is~57 Ibid., 334.60 Abstr., 1907, i, 950.m Abslr., 1907, i, 146.58 Ibid., 1892, 1318.Bid., 331.Zbid., 1904, i, 54.162 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.to be preferred, and shows that the ‘* glyoxime peroxides ” are convertedinto the corresponding furazans by the action of phosphorus penta-chloride.Thiophen and Thiusoles.By the action of mercuric acetate on thiophen, Dirnroth 66 obtaineda compound to which he gave the constitutionC,H2(Hg*O*CO* CH,)(HgOH)S ;this is corrected by P a ~ l i n i , ~ ~ who uses the substance for the isolationof thiophen, to C4H,(HgO*C0.CH3),S.thionessal ”(tetraphenylthiophen) showing that it may be produced by the drydistillation of sodium thiobeuzoate, and Fromm and Holler 69 examinethe results obtained by Engler 70 from distillation of the product ofthe action of hydrogen sulphide on acetophenone.Fromm andHoller find that it is neither a thiopinacone nor disulphide, but amixture of sulphur and 2 : 4-diphenylthiophen.von Walther and Greifenhagen 71 have obtained substituted thiazo-lines by the interaction of bromoacetophenone and diary1 t hiocar bamides,thiocarbamides, or thiourethanes.Fromm and Schmoldt 6* describe several syntheses ofiso Oxuxolones.In addition to the work of Moureu and Lazennec already referredto under pyrazolones, we may note the production of oximinophenyl-isooxazolone by Wahl from ethyl isonitrosobenzoylacetate,72 andReissert’s production of anthranil by the decomposition of o-nitro-dimercaribenzylidene oxide, N0,*C6H,*CH:Hg,:0, with hydrochloricacid.73Pyridine and Piperidine.The behaviour of piperidine vapour and of pyridine vapour mixedwith hydrogen towards reduced nickel has been examined by Sabatierand Mailhe 74 as well as by P a d ~ a . ~ ~ The authors find that piperidinegives pyridine, but pyridine and hydrogen do not give piperidine ; in thedeviation from the behaviour of benzene, Sabatier and Mailhe see anargument against Korner’s pyridine formula.The wandering of alkyl groups in the pyridine series has engagedthe attention of H.Meyer the first observation that 4-methoxy-pyridine gave N-methylpyridone a t 220’ being due to Haitinger andLieben.66 Abstr., 1899, i, 428.63 Ibid., 702.7O Ber., 1895, 28, 895.T2 Ibid., 217.74 Ibid., 549. Ibid., 636.76 Ibid., 343,(i7 Ibid., 1907, i, 788.6g Ibid., 710.i1 Abstr., 1907, i, 349, 551.i 3 Ibid., 1103ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. 163Somewhat similar changes with the esters of pyridinecarboxylicacids were observed by Kirpal ; 77 for instance, apophyllenic acid isproduced by the isomerisation of either of the acid monoethyl esters-of cinchomeronic acid. Meyer has now examined several acids derivedfrom pyridine and quinoline containing alkyloxy-groups in the 2- andcarboxyl in the 3-, 4-, or 5-position, but in no case was a wandering of thealkyl to nitrogen observed, although where the carboxyl and methoxylgroups are in the meta-position relatively to one another the methylgroup wanders so as to give a carboxylic ester.Zincke publishes with Schreyer 78 a further communication on thetransformation products of dinitrophenylpyridinium chloride ; Barthe 79describes new mono- and tri-bromopyridines, whilst B.Oddo,80 inexamining the compounds of pyridine and quinoline with magnesiumphenyl bromide, finds that one molecular proportion of the latterunites with one, two, or three molecules of quinoline. New stilbazolesare described by Ahrens and Luthers1 and Lowensohn,S2 whilstOrtolevas3 continues his study of the substance obtained by theaction of iodine on a pyridine solution of benzaldehydephenyl-hydrazone.The physical properties of pyridine derivatives have engaged someattention.F. Baker and Balys4 find that introduction of methylgroups or chlorine atoms into the pyridine nucleus, whilst it reducesthe oscillation frequency, does not alter the type of the absorption.From the absorption spectra of the hydroxypyridines, it is concludedthat the P-compound is phenolic, but that the U- and y-derivatives arepyridones.Kirpal 85 has determined the dissociation contents of the isomericester-acids produced by quinolinic and cinchomeronic acids, and Kailan 8Bhas measured the velocity of esterification of pyridinemonocarboxylicacids by alcoholic hydrogen chloride.A number of tetrahydropyridine bases are described by W.Koenigs,Bernhart, and IbeleY87 whilst K. Lofflers8 has (in conjunction withPlocker, Grosse, and Grunert) prepared a number of conidine bases,the attempt a t synthesising conidine itself being unsuccessful.A piperidine synthesis from ethyl acetonedicarboxylate, aldehydes,and primary amines is given by Petrenko-Kritschenko and M. Lemin,sgand Gabriel and Colman find that, when the isomerisation product of1 -y-chloropropylpiperidine is distilled with potash, some I-y-hydroxy-77 Abstr., 1902, i, 564 ; 1903, i, 117, 852.Ibid., 792.*l Ibid., 965.s3 B i d . , 729.as Abstr., 1907, i, 722.s7 Ibid., 1907, i, 791.89 Ibid., 708. ]bid., 237.7a Ibid., 1907, i, 625.so Ibid., 549, 668.a2 Ibid., 1908, i, 51.Trans., 1907, 91, 1122.86 Ibid., ii, 678.88 Ibid., 437, 439, 440, 441.M 164 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.propylpiperidine is produced.In this, they see a further proof thatthe condensation product of 1 - y-propylpiperidine is unimolecular.Other work which bears on this question is contained in a paper byJ. von BraunQ1 on the action of piperazine on a€-dihalogenpentanes.Finally, Franchimont, van Rijn, and Friedmann 92 have studied theaction of nitric acid on various piperidides, and find that those ofsuccinic and sulyhuric acids give nitropiperidine.Quinoline.Blaise and Maire93 find that 4-alkylquinolines can be readilyprepared by heating aniline with ketones containing a P-chloroethylradicle; von Niementowski 94 finds 4-anilino-2-hydroxyquinoline amongstthe products of interaction of ethyl benzoylacetate and anthranilicacid, whilst 0.Stark,g5 in an attempt to dehydrate the oxime of3-acetyl-2-methylquinoline, obtained 3-amino-2-methylquinoline as theresult of a Beckmann transformat ion accompanied by hydrolysis of theacetyl groups.B. Odd096 finds that, not only does magnesium phenyl bromidecombine with different molecular proportions of quinoline, but that,when bromobenzene, quinoline, and magnesium are allowed t o interactin toluene solution, 2-phenylquinoline is produced.L,. J. Simon and M a ~ g u i n , ~ ~ examine the mechanism of Dobner’sreaction, and employ a-naphthylamine, pyruvic acid, and benzaldehydeas components ; H.Meyer and Turnau 9s give details of the preparationof quinoline-2-carboxylic chloride by means of thionyl chloride, whilstOmstein99 extends the work of Rlulert and Pfitzinger 2 on derivativesof 3-methylcinchonic acid. I n a paper on cases of steric hindranceamong alky 1 substituted cinchonic acids, Hans Meyer 3 incidentallycorrects a number of errors in the dissertations of Ornstein (Berlin,1904) and Mulert (Berlin, 1904).A cridirte.Senier, with A ~ s t i n , ~ has investigated the conditions under whichmixed phenonaphthacridines may be obtained by the methylene iodidemethod and, with C~mpton,~ the production of simpler substitutedacridines when methylene chloride is used. Bucherer and Seyde 69l Abstr., 1907, i, 728. Jbid., 842.93 Ibid., 241.95 Ibid., 973.Ibitl., 549.99 Jbid., 443.94 Ibid., 1081.g7 Ibid., 725. 98 Ibid., 344.Ibid., 1906, i, 534.Ibid., 1907, i, 342.Ibid., 1927.Ibid., 1903, i, 53.Trans., 1907, 91, 1233, 1240.6 Ahntr. 1907. i. 34.4ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. 165employ formaldehyde and nitrous acid with diarylamines, and A. E.Dunstan and Hilditch have condensed diphenylamine with p-bromo-and chloro-benzoic acids.I n the production of acridones, aryl substituted anthranilic acidsare necessary, and the conditions under which the chlorine in o-chloro-benzoic acid may be replaced by arylamino-grmps have been studiedby Ullmann.7 The best catalyst is a small quantity of a copper salt,and Irma Goldberg and Marie Nimerovaky * find that the presence ofa small quantity of copper enables the further phenylation ofanthranilic acid to diphenylanthranilic acid.It is necessary, however,to use iodobenzene as bromobenzene is inactive.A number of acridones have been prepared from the arylaminobenzoicacids mentioned, and Ullmann (Zoc. cit.) finds that, whilst the introduc-tion of halogens into the acridone molecule has practically no effect onthe fluorescence, this property is nearly inhibited by nitro-groups. Ofthe aminoacridones, the 2- and 4-derivatives fluoresce strongly inalcoholic solution, whilst the l-amino-compound does not ; on additionof hydrochloric acid, the conditions are reversed, the 5uorescence of the2- and 4-compounds disappearing, whilst the l-aminoacridone hydro-chloride exhibits the property.Goldberg and Nimerovsky (Zoc.cit.) have obtained the hitherto un-known 1 O-phenylacridone from the dehydration of diphenylanthranilicacid, and Ullmann and Maag find that the substance gives a colourlesscarbinol base with magnesium phenyl bromide which dissolves in acids,giving solutions of acridinium salts; these possess a yellow colourand green fluorescence. In a later paper,lO Ullmann, Bader, andLabhard t find that acridine itself readily condenses with dimethyl-aniline in presence of phosphoryl chloride to furnish 5-p-dimethylamino-acridine.Diaxines.Paal and Kuhn l1 continue the synthesis of o-diazines, whilst thern diazines, since they include the pyrimidines, have engaged muchattention.The most important syntheses in the latter group are dueto T. B. Johnson, H. L. Wheeler, and their co-workers (F. W. Heyl,C. 0. Johns, and C. F. Speh),12 and an example of the methodemployed by these chemists was given in last year's Report (p. 173).Studies are being made of the behaviour of various carboxylic acids ofthe series towards hot 20 per cent. sulphuric acid with the view of ob-taining information as to the manner in which the pyrimidines arebound up to the nuclein molecules.7 Abstr., 1907, i, 842.l1 Zbid., 1908, i, 57.l2 Ibid., 1907, i, 559, 728, 877, 879, 972, 1083; 1908, i, 59.8 Ibid., 621.lo Ibid., 1908, i, 52. Ibid., 638166 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.As an example, cytosine-5-carboxylic acid is found to be convertedinto urscil-5-carboxylic acid by the treatment whereby cytosine isisolated from the nucleic acids.Evidently, then, the latter substancescannot contain the cytosine-5-carboxyl grouping.I n order to find out whether some of the pyrimidine derivatives ob-tained by the hydrolysis .of nucleic acids with moderately concentratedsulphuric acid may not be formed from purine bases by hydrolysis andreduction, Burian l 3 has heated dextrose with diluted sulphuric acid(30-40 per cent.), adenine, and guanine. The result is positive,6-aminopyrimidine being obtained from the first base, and 2-amino-6-oxypyrimidine (isocytosine of Wheeler and Johnson) from thesecond.The oxidation of uracil derivatives has been studied by Hoebell*and Offe,l5 the work being a continuation of that of Behrend.16The colours exhibited by the condensation products of aromaticaldehydes with diphenylbarbituric acid obtained by Miss Whiteley 17are striking, the benzylidene derivativo of 1 : 3-diphenylbarbituric acidoccurring in two forms, one yellow and the other colourless; the di-phenylmethylene derivative is yell0 w, whilst the product from cinnam-aldehyde is orange-yellow.Hantzsch assigns the respective formulae :NH--C---Y/C:NO*OM \ and GO\ / /C-NO OM \\NH*COto the colourless and coloured salts of nitrobarbituric acid.Tafel and H.B. Thompson l9 have submitted 5 : 5-diethylbarbituricacid (veronal) to electrolytic reduction; it is more difficult to reduce thanbarbituric acid itself, and, instead of giving a hydrouracil, furnishes 4 : 6-diketo-5 : 5-diethylhexahydropyrimidine.Einhorn and von Diesbach 2Ofind that veronal is not attacked by sodium amalgam, but the corre-sponding diethylthiobarbituric acid is readily reduced by this reagent,a portion of the substance undergoing fission, and another portion givingthe hexahydropyrimidine compound described by Tafel and Thompson,whilst the remainder forms a condensation product which is probablybisdiethylmalonyltetraminoethane. A * 2-phenyl derivative of Tafeland Thompson's product has been produced by Burrows and Keane,21who condensed diethylmalonamide and benzaldehyde in presence ofhydrochloric acid.I3 Abstr., 1907, i, 735.l5 Ibid., 645.l9 Ibid., 1908, i, 58.21 Trans., 1907, 91, 269.l4 Ibid., 557.I6 Ibid., 1900, i, 120 ; 1903, i, 739 ; 1906, i, 310.Trans., 1907, 91, 1330.Abstr., 1907, i, 500.Ibid., 110ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. 167Franchimont and Friedmann 22 find that hydrouracil and tri-methyleneureine yield mono- amd di-nitramines respectively, asupport of Franchimont's theory that the replacement of the hydrogenof an imino-group by the nitro-group is conditioned by the imino-groupbeing situated between a carboxyl and the residue of a saturatedhydrocarbon.Delepine 23 regards aldehyde-ammonia as the hydrate of a cycliccompound, t riet h y lid ene tria mi n e, and the hexaet h ylidene te tramine asalso possessing cyclic structure. The respective formulae are :CH2<cH(CH8)-NH N)CH*CH2\CH,*CH, .NH/CH--- >CH-NH/\cH(cH,): CH,.I n the purine group, Tafel's work on the electrolytic reduction ofuric acid (isopurone, jointly with Houseman 24), theophyllino, and para-xanthine (with Dodt 25) may be noted, whilst H.Schulze has studiedthe action of magnesium phenyl bromide on caffeine and certainderivatives. 26Hydurilic acid, which was discovered amongst the products of inter-action of nitric and uric acids by S~hiefer,~7 has finally beensynthesised by Conrad.28 The guanide obtained by condensation ofethyl ethanetotracarboxylate is the di-imide of hydurilic acid, which itfurnishes on heating to 156' with dilute hydrochloric acid :Amongst quinazolines, a number have been synthesised by Bogert z9and his co-workers, Wiggin, Sinclair, Seil, and Nelson.Parccdiazines.Pyrazine, C4H4N2, has been obtained from quinoxaline by Gabrieland Sonn,m the latter compound being oxidised by alkaline per-manganate to pyrazinedicarboxylic acid, from which carbon dioxide issubsequently removed.2j Absty., 1907, i, 877.23 Ibid., 484.24 Ibid., 984. 25 Ibid., 984.26 Ibid., 545. 27 Annnlcn, 1545, 55, 251 ; 1845, 56, 1.2i3 Abstr., 1907, i, 985. 29 Ibicl., 351, 560, 660.30 Ibid., 1908, i, 60168 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Both oxalimide and the anilide of pyruvic acid have been referredto the piperlizine series, de Mouilpied and Rule 31 ascribing to theformer the constitution (I), whilst Wohl and Lipss2 give the latter,structure (11) :(1- ) (11.)Amongst the azine colouring matters, 0.Fischer and Romer33confirm Kehrmann and Prager's view s4 that, when hydroxylaminereacts with isorosindone, the amino-group enters the ortho-position tothe quinonoid oxygen of the benzene nucleus and not the naphthalenehalf of the molecule as at first supposed : 35Barbier and Sisley 36 prepare aposafranine by heating p-aminoazo-benzene hydrochloride with aniline, its hydrochloride, and water at160-170° ; they give the following explanation of the mechanism ofthe reaction :(I) C6H5*N:N*C,H,*NH2 -+ANR. Scholl h i s published several further papers on indanthrer1e,3~and has elucidated the structure of the flavanthrene discovered byR. Bohn amongst the products of fusion of /I-aminoanthraquinonewith potash, The probability of the substance possessing the con-stitution required by the equation :3l Trans., 1907, 91, 176.32 Abstr., 1907, i, 583.33 Ibid., 981.35 Ibid., 94.37 Ibid., 255, 256, 354.34 Ihid., 447.36 Ibid., 563ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION. 169has been confirmed by synthesis.Triccxines.Derivatives of 1 : 2 : 3-txiazines (triazones) have been produced byH. Meyer3s by the action of nitrous acid on the aromatic analogues ofpolypeptides. The latter subst,ances are prepared by the action ofo-nitrobenzoyl chloride on lithium rtnthranilate :NO,*C,H,*COCl+ NH,*C,H,*CO,Li =Licl+ NO2 c,H,* 00 *NH C,H,* C02H(repetition of the process if desired) and, finally, reduction of the nitro-to an arnino-group.The action of nitraus acid may be expressed by the equation :N/\ + HNO, = 2H20 + 1 A N H , /\I IC0"H-I I .,J,,,,!N--!,,~ \/ co CO,H\/C02HThis compound is ruptured by hydrogen chlonide to a dinzonium saltand, finally, salicylanthranilic acid, which condenses with aceticanhydride in the following manner :C02H 'w\O1 : 2 : 3-Triazine derivatives have been prepared by Bailey andKnox 39 and M.Busch and Meussdorffer 40 ; Ley and F. Muller 41 havesynthesised a dihydro-1 : 3 : 5-triazine derivative, and Finger 42 hasprepared the trihydrazide of cyanuric acid and some of its derivatives.Pyrone G~oup.Rlaise and Qeult43 publish several papers on pyran and pyroneThe attempt of Fleischmann 4433 Abdr., 1907, i, 317.41 l b i d . , 730. Bid., 298. 43 lbid, 148, 181, 332.44 Trans., 1907, 91, 250.derivatives from aediketopimelic acids,39 Ibid., 801.40 Ibid., 448170 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.to obtain a yy-dipyrone by condensation of triacetic lactone withacetoacetic ester or b-aminocrotonic ester proved unsuccessful, alactone being produced instead, whilst Collie and Hilditch 45 find thatwhen dehydracetic acid is heated with sulphuric acid of 85 instead of90 per cent. very little triacetic lactone is formed, but a substance,C8H804, which decomposes nearly quantitatively at 200' into dimethyl-pyrone and carbon dioxide is chiefly obtained. The formulaproposed by Collie for the product of the action of sulphuric acidon dehydracetic acid, which in its enolic form would bereceives confirmation from Tamburello and C a r a ~ e l l i , ~ ~ who haveconverted the substance by means of diazomethane into thecorresponding methoxymethylpyrone.Bain 47 has examined thebehaviour of the disodium derivative of diacetylacetone towardsethylene and propylene dibromides, thus extending his earlier ~ o r k . ~ 8Amongst chroman compounds, W. H. Perkin and R. Robinson49have made experiments on the synthesis of compounds nearly relatedt o trimethylbrazilin, which is possibly0CH~*O~\/\CH---/\O*CH,\/\/ \/\/ I ICH I IO*CH;CH*OH CH,Salicylaldehyde and 1 -hydrindone condense t o give 2'-hydroxy-2-benzylidene-1 -hydrindone, which is reduced then t o 1 : 2'-dihydroxy-2-benzylhydrindene. Loss of water furnishes 1 : 2-hydrindochroman, theseries of changes being represented by the scheme :0By replacing the salicylaldehyde with its p-methoxy-derivative andusing 5 : 6-dimethoxy-l-hydrindone in place of hydrindone itself, a45 Trans., 1907, 91, 787.47 Trans., 1907, 91, 544..m Ibid., 1907, 91, 1078.46 Gazxetta, 1907, 37, i, 561.Ibid., 1906, 89, 1224ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION.17 1substance was obtained which, if the above formula for trimethyl-brazilin is correct, merely differs from it by a hydrogen atom in placeof a hydroxyl group.von Kostanecki 5O publishes further syntheses in the flavane group,starting with cuminaldehyde, and C. Liebermann, S. Lindenba~ru,~~and Truchsiiss 52 continue the work on xanthophanic and glaucophanicacids.Further syntheses of xanthone derivatives, starting with o-chloro-benzoic acids, are published by Ullmann and C.Wagner,53 andWichelhaus 54 has examined the action of sulphur on fluorescein.The question of the constitution of phthalein salts has led R. Meyerand K. Marx55 to make a spectroscopic comparison of fluorescein andthe phthaleins of phenol and quinol in alkaline solution. It is foundthat the two latter substances are very similar, but differ markedlyfrom fluorescein. Further, Meyer and J. Stark 56 have compared thefluorescent spectra in alcoholic and sulphuric acid solution both in thecase of fluorescein and fluoran. With the first compound, the solventmakes little difference, with the second compound the influence of thesolvent is most marked, and the result is attributed to formation ofoxonium salts, a conclusion arrived a t by Hewitt some years back.57That apparently minor differences in constitution can have consider-able influence on fluorescent phenomena appears from the descriptionof a number of fluoresceins by Friedl, Weizmann, and W ~ l e r .~ ~Oxnxines.The labile changes occurring between 0- and N-acylsalicylamideshave been ascribed by McConnan and Titherley 59 to cyclic tautomerism,N-benzoylsalicylamide being represented in its labile form by thestructure :This view is controverted by Auwers,gO but Titherley 61 now showsthat the phenylbenzometoxasone obtained by Keane and Nichollsfrom salicylamide and benzaldehyde can be oxidised in sulphuric acidsolution to N-benzoylsalicylamide, a result which might be simplyexpressed by the equation :50 Abstr., 1907, i, 952.52 Ibid., 890.53 Ibid., 846. 54 lbid., 232. 55 Ibid., 932.56 Ibid., ii, 418. 58 Yrarbs., 1907, 91, 1584.59 Ibid., 1906, 89, 1318. Yrans., 1907, 91, 1419.6‘2 Ibid., 264.51 lbid., 889.57 Ibid., 1900, ii, 318.6O Abstr., 1907, i, 928172 AKNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Other p-oxazines and azoxonium salts are described by Kehrmannand Albert Winkelmann 63 and Nietzki and V. Be~ker.6~ J. F. Thorpe 65finds that dye-stuffs of the general formula (I) lose NHR,R, on pro-longed boiling with dilute acids, furnishing dialkylaminophenonaphth-oxazones (11) :0Meldola’s blue gives the same product, but the reaction in this casenecessitates simultaneous oxidation.Amongst the allied thiazine compounds, h e h m 66 has studied theaction of nitric acid on methylsne-blue and its homologues, the tetra-ethylthionine being far more reactive than the tetramethyl com-pound (met hylene-blue).Vuriouus Rings.Amongst unclassified cyclic structures, we may note the constitutionassigned by \Vieland 67 t o ‘‘ hydroxyleucazone,”the thianthrene compounds of J.Frohlich,6s which are derived fromS o-diphenylenedisulphide, C,H,<s>C6H,, and the continuation of thework on oxadiazines by Diels and Sa~se.6~Alkaloids.A control of the constitutions of tropine, ecgonine, cocaine, andbenzoylecgonine has been effected by G a u d e ~ h o n , ~ ~ who finds that theheats of formation of the alkaloids correspond with the constitutionsassigned to them.Ldger 71 has confirmed the constitution of hordenine as p-hydroxy-phenylethyldimethylamine, for the methiodide of its methyl ether givesp-vinylanisole when heated with alkalis, and Willstatter and €€eubnerT2find that tetramethyl-as-diaminobutane accompanies hyoscyamine inHyoscyamus muticus.63 Aktr., 1907, i, 345, 554.65 Ibid., 978.67 Ibid., 1907, i, 494.70 ]bid., ii, 738.64 Trans., 1907, 91, 324.66 Abstr., 1908, i, 63, 110.6* Ibid., 632.71 Ibid., i, 234, 336.69 Ibid., 1086.‘i2 Ibid., 959ORGANIC CHEMISTRY --HETEROCYCLIC DIVISION. 173Barger and Carr 73 have confirmed as a fact the suggestion of Kraff t 74that ergotinine is derived from ergotoxine by removal of the elementsof water, and assigns t o the two alkaloids the respective formulEe~,,J339O,N, and C,,H, 106%.About two years ago, Pictet made the suggestion that the vegetablealkaloids owe their formation to the following processes :1.The complex tissue materials, albumin, nucleins, chlorophyll, &c.,break down, giving relatively simple products.2. These simple bases then condense with other materials to formthe more complicated alkaloids.A systematic examination of various plants with a view of sup-porting this hypothesis has led to the isolation of pyrrolidine andN-methylpyrroline from tobacco, a base, C,H,N (probably a C-methyl-pyrroline), from pepper, pyrrolidine and a base, CllHI8N2, from carrotleaves, and a base, C,H,,ON, from coca, which is, however, notidentical with Liebermann’s hygrine.The knowledge of the betel-nut alkaloids has been materiallyextended by Wohl’s researches on amino-acetals and amino-aldeh~des.7~Ammonia reacts with chloropropalde hy de acetal,giving a mixture of primary, secondary, and tertiary bases.Thesecondary base by hydrolysis with hydrochloric acid furnishes thehydrochloride of A3-tetrahydropyridine-aldehyde, and if the corre-sponding N-methyl-A3-tetrahydropyridine-aldehyde (obtained by sub-stitution of methylamine for ammonia in the first reaction) is convertedinto the corresponding carboxylic acid,CHit is found to be identical with arecaidine. This alkaloid (and arecoline,its methyl ester) had been previously synthesised by Jahns,76 but theposition of the double linking was unknown.A.Ladenburg 77 now finds [aJD 17.85’ for pure isoconiine; thevalue previously obtained (19.2’) was too high, and probable due toadmixed allylpiperidine.Ladenburg states that for a tropeine to possess mydriatic properties,it must contain an acyl group attached to the benzene nucleus, and73 Trans., 1907, 91, 337.77 162.’ 1907, i, 956.7J Abs.fr., 1906, i, 979.75 Ibid., 1908, i, 46. 76 md., 1892, 737174 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.have an aliphatic hydroxyl in the side-chain.have synthesised a compound of the structure :Jowett and Pymm 75? /\CO--j J C H ( o ~ ) * C H * C O * c ~ H , , O N ’but its physiological action is feeble.Rabe’s formula for cinchotoxine bas received ample confirmation,two posthumous papers of W.Koenigs 79 definitely proving the hydro-lytic products required Iny the formula C,H6N*CO* CH2*CH,*C7H,,Nare obtained when Beckmann’s transformation is applied to the oximeof Rahe’s l-methylcinchotoxine.80Though the cinchotoxine formula is settled, it should be noted thattwo possible formuls remain for cinchonine itself, namely :CH-/?H-.y 3 2 ?%7H2 / 7H2 ’ ‘CH*CH:CH, I\CH*CH:CH~ CH, CH2and YH\’ / QHzYH2 t‘H, N-- HO* ?--N-- / CH-OHIC A N C9H6NP. Rabe 8J finds that when isonitrosomethylcinchotoxine is submittedto the Beckmann reaction, methylcincholeupone nitrile and cinchoninicacid result, whilst he has further investigated the behaviour ofcinchonine towards nitric ** and chromic 83 acids. The substanceobtained in the second case is apparently a ketone derived from analcohol (the cinchonine) by removal of two hydrogen atoms, so thatit would appear that the second formula given above for cinchonine isreally correct.Rate 84 gives us further evidence in favour of this formula, namely,the conversion of narcotine and gnoscopine (racemic narcotine) into aketone-base, nornarceine, by heating with dilute acetic acid ; hydrolysisalso occurs with formation of cotarnine and meconine, but the change tonornarceine may be represented as follows :CH,788083O*CH,CO/\CO,H (/o*cH,0.CH,.Trans., 1907, 91, 92.Ibid., 71. 8l Ibid., 546. 82 Ibid., 546.Ibid., 954. Ibid., 790.T9 Bernhart and Ibele, Abstr., 1997, i, 345, 717ORGANIC CHEMISTRY-HETEROCYCLIC DIVISION.175The analogy to the conversion of cinchonine into cinchotoxine isapparent when one compares the narcotine lactone formula with thesecondary alcohol formula for cinchonine.Rohde and Antonaz s5 find that the sodium derivative of methyl-cinchotoxine is readily oxidised (by nitrobenzene in alcoholic solution),giving a quinoline-y-carboxylic acid ; the meroquinenine half of themolecule appears, however, in an unworkable condition.Pictet and Jenny have examined the amine-oxide,C23H&5N2,4& H,O,from brucine and hydrogen peroxide; Pavesi 87 has found a newalkaloid, aporeine, in the latex of Papaver dubizcrn, and M. Freund 88 hasrevised Tambach and Jager’s work on n a r ~ e i n e . ~ ~M. Freund and F. Mayergo adopt Gadamer’sgl modification ofPerkin’s formula for berberit~e,~~ which makes the free base an aldehyde,but the berberine salts as of quaternary isoquinolinium type. Theformula of Gadamer would necessitate two asymmetric carbon atoms inan alkyltetrahydroberberine, and Freund and Mayer actually find that,when propyldihydroberberine is reduced, t w o racemic propyltetra-hydroberberines are formed.The morphine group of alkaloids has been the subject of extensiveinvestigations during the past year by LeesYg3 Knorr and Horleinyg4Pschorr,gS and Vongeri~hten.9~A certain amount of uncertainty as to isomorphine (and isocodeine),P-isomorphine (and P-isocodeine), and neo-iso- (or y-iso-) morphine (andpseudo-codeine) is cleared up by Lees’ classification of the geneticrelationships :P-isoMorphine f- Chloromorphide -+ Neo-isomorphine.1J. .5.I I + Chlorocodide -+ Neo-isoCodeine.J.P-is0 CodeineP-isoMorphine +- Bromomorphide -+ isoMorphineP-isoCodeine f- Bromocodide -+ isocodeine.I I +The nomenclature in the scheme is that used by Lees; in readingKnorr and Horlein’s papers it must be remembered that isomorphineis referred to as a-isomorphine, P-isocodeine as allo-$-codeine, neo-iso-morphine as y-isomorphine, and neo-isocodeine as +codeine.Whilst codeine and isocodeine both give codeinone on oxidation,a5 Abstr., 1907, i, 634.a8 Ibbid., 235.Ibid., 1902, i, 555.93 Ibid., 1907, 91, 1408.91 Abstr., 1907, i, 235, 547, 548, 789, 956, 957 ; 1908, i, 41, 4‘2.95 Ibid., 1907, i, 547, 635, 636, 958.86 Ibid., 436. 87 Ibid., 870.d9 Ibid., 1906, i, 879.y2 TTans., 1889, 55, 63 ; 1890, 57, 991.Ibid., 1907, i, 632.Ibid., 718, 1068176 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.p-iso- and neo-iso-codeines give q-codeinone, the two isomeric ketonesdiffering in melting point (1S7O and 174’ respectively) and values ofaD ( - 2 0 5 O and - 25O). Vl’hilst the isomerism of codeine to isocodeineis sterical, the same being true of the other pair of (p- and neo-) iso-codeines, oxidation of the secondary alcoholic grouping to a ketonemakes this form of isomerism disappear, and hence only twocodeinones are produced from the four codeines. The codeinones are,however, structurally different, codeinone can be degraded to 3 : 4 : 6-trimethoxyphenanthrene and the 3 : 4 : S-isomeride being obtained fromq-codeinone. Evidently some deep-seated change occurs during theformation or hydrolysis of chloro- and bromo-morphides.Hitherto both Knorr and Pschorr have been in substantial agree-ment as to an oxide-bridge between positions 4 and 5 of thephenanthrene nucleus, and the attachment of the nitrogen atom of thechain CH,*N*C*C* to position 9, but quite recently Bucherer97 hasproposed an entirely novel formula. The three proposed coustitutionsfor morphine are as follows :C H CH CHH O ~ \ \ C H/\/\/CH, C H CHI ’ I IN-CH CH”I I \ /CH, OHCH,Pschorr. Knorr. Bucherer.Bucherer’s formula has not yet been thoroughly discussed, butKnorr in a footnote to his last papergS thinks that in a modifiedform (as below) it may be worth considering. Unmodified, it requiresCH, C H0 C Hthat codeinone and thebainone should be secondary bases, which is atvariance with the facts of the case. J. T. HEWITT.97 Abstr., 1908, i, 43. 93 Ibid., 42

ISSN:0365-6217    

DOI:10.1039/AR9070400138

出版商:RSC    

年代:1907

数据来源: RSC

摘要:

STER EOCHEMI STRY.THE work on stereochemistry published during the past year isvoluminous, and is the result of considerable activity on the part of avery large number of investigators ; much of the work recorded hasserved rather to establish more firmly the fundamental theories ofthis branch of the subject than to break fresh gi ound for investigation ;there are, however, several cases to which this remark does not apply.Notable among the parts of the subject which have received mostattention is the quantitative study of optical rotatory power ; the resultsobtained have, however, shown more clearly than ever the enormousinfluence which the chemical nature of the groups attached to theasymmetric atom may exert on the rotatory power of a compound, aninfluence which, i-n some cases, completely outweighs that of the weightof the group, The influence of solvents on rotatory power has alsobeen extensively studied, and there now appears to be some prospect ofacquiring a reasonable understanding of these effects, which appear tobe due so largely to internal pressure and changes of volume causallyrelated to it.A very prominent position among the important contributions to thisbranch of chemistry must be accorded to the work of Fischer, whichhas thrown some light on that surprising change usually termed the(6 Walden inversion,” and clearly shows the importance of the study ofstereochemical changes as a means of elucidating the internal mechanismof chemical reactions, and also to the work of Kipping in addinganother element, silicon, to those whose atoms have been shown to becapable of exhibiting optical activity.The problem attacked simultaneously by Marckwald and Meth andby Perkin and Pope, namely, the production of an optically active com-pound whose activity, was due to asymmetry of the molecule and notto the asymmetry of any single atorn,l remains still in the same stateas last year.I n order to settle the question definitely, both the acidsto which the formulais assigned must be resolved.Ann. Report, 1906, 185.REP.-VOL. 1V. 178 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The quantitative study of optical rotatory power and its relation tochemical structure has been the subject of a large number of papers,among which the following occur.Chardin and Sikorski contribute an interesting paper in which theydevelop Guye’s hypothesis and deduce some valuable results.Guye’s original expression for the product of asymmetry involvesquantities determining the spatial position of the centre of gravity ofeach of the four groups attached to the asymmetric carbon atom.I nthe present state of our knowledge of the forces which determinechemical combination, we hjve no means of determining these quantities ;hence Guye simplified his expression by making two assumptions : (1) thatthe centres of gravity of the groups are situated on the axes of theasymmetric carbon atom, and (2) that the distance of the centre ofgravity of each group from the centre of gravity of the carbon atom isthe same, thus obtaining the well-known expression for the product ofasymmetry involving only the weights of the four groups.The enormous mass of statistical evidence accumulated by Guye,Walden, Frankland, and others shows that this expression is inadequateto explain the experimeutal results.The authors conclude that thefirst assumption made by Guye is justified, and develop formulae forthe calculation of the ‘‘ atomic product,” that is, the product of theweight of an atom or group and its distance from the carbon atom incertain simple cases. This quantity they find to be a constant for eachseries in the periodic table.The further development of the views of these authors will be awaitedwith interest; but i t will be surprising if it can be shown that the4 c atomic product ” is determined by the nature of the group in questionalone and is independent of the other groups attached to the carbonatom.discusses the conditions utider which a collection ofatoms, each consisthg of electrified parts rigidly connected together,can exhibit optical activity, and deduces an expression for the opticalactivity which satisfies the necessary conditions.This theoreticaldevelopment is, however, inapplicable to concrete cdses in the presentlimited state of our knowledge.Betti makes an important contribution to our knowledge of theinfluence of the chemical constitution of a group, as distinct from itsweight, on the rotatory power of the asymmetric carbon atom to whichit is attached.This worker has determined the specific rotatory powers in benzenesolution of a number of substances having the general formulaJ.J. ThomsonAbstr., 1907, ii, 830.Proc. Cnmb. Phil. Xoc., 1907, 14, 313.Abstr., 1907, ii, 661, 726STEREOCHEMISTRY. 179B C,H,-Y-N:CH*RC,,H,*OHand derived from d-a-aminobenzyl-/l-naphthol by the action of aromaticaldehydes. The original base was isolated by means of d-tartaric acid,and gave [.ID + 58.9'. The compounds formed with twenty-one differentaromatic aldehydes were examined ; a few only of the more strikingresults can be mentioned here :Benzaldehyde compound ............................o- Me thoxybenzaldchyde , , ...............p-Methoxybenzsldehyde , , ...............5 Broiiiosalicylaldehyde , , ..............5-Bromo-2-methoxybenzaldehyde compound ...Salicylaldehyde , , ..............................p-Hydroxybenzaldehyde compound ...............o-Nitrobenzaldehyde ...............p-Nitrobenzaldehyde ...............,,1 ,[a], + 110'72" ,, -15'65 ,, +297*3 ,, +243'6 ,, +314'4,, +54-29,, -259.36,, -76'37 ,, +39'45The remarkable difference between the values of [a]D for compoundsi n which the group R has the same weight and differs only in the posi-tion of a substituting group in the benzene nucleus is well illustratedin the cases quoted. The hydroxy- or nitro-group in the ortho positionto the point of attachment of the radicle R to the asymmetric carbonatom exerts so great an influence on the rotatory power that even itssign is altered ; the presence of a methoxy-group in the same positiondoes not have this effect.It may therefore be concluded that theeffect is due to a disturbance in the relative positions of the fourgroups, caused by bringing a group of acidic or electronegativecharacter near the other groups. It is concluded that an electro-negative group increases the lajvorotation of the molecule, an effectclearly shown in the bromo- derivatives of salicylaldehyde ando-methoxybenzaldehy de.This work clearly shows that Guye's hypothesis in its simplifiedform could, at best, only apply to small groups of closely alliedcompounds.It is interesting to contrast with the work last mentioned, in whichthe influence of the chemical nature of groups is so prominent, theresults obtained by Pickard and Littlebury 5 for the rotatory powersof esters of Z-menthylcarbamic acid, C,oH,,NH*CO,H, in which thehydrogen of the carboxyl group is replaced by a group R.This workis a continuation of that described in 1906.6 The molecular rotatorypower of the esters in chloroform solution only varies from 162' to165.5' when R is a normal aliphatic group, but it may vary from 158't o 169' when R is a secondary aliphatic group, and from 150' to 162'Trans., 1907, 91, 300. Ibid., 1906, 89, 94.N 180 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.when R is an aromatic group either of the benzene or naphthaleneseries. Similar relations hold for solutions in pyridine and in alcoholand for substituted amides of Z-menthylcarbamic acid of the typeC,,H,,NH*CO*NH*R, where R represents the same alkyl groups ;the molecular rotatory power of these compounds is about 160’.Within the range of the small differences observed, the rotation ofcompounds containing the o-tolyl, phenyl, m-tolyl, and y-tolyl groupsincreases in the order given, as would be expected from Guye’shypothesis.The small influence of changes in the constitution of the radicleR is remarkable, and is probably due to the fact that these changestake place relatively far away from the asymmetric carbon atomsin the menthyl complex, so that comparatively little disturbance isproduced in the equilibrium positions of the groups attached t o theasymmetric carbon atoms in the ring.Tschugaeff and Sokoloff ,7 by examining the metallic nmminesderived from Z-propylenediamine, add another instance of the greatirifluence of ring formation on rotatory power to those alreadyrecorded.Werner came t o the conclusion that these compounds hada cyclic structure, and these author3 show that the compoundsderived from the lsvorotatory base are all dextrmotatory.Patterson and Kayes have now completed the study of theZ-menthyl diacetyltartrates, which was undertaken with the object oftesting the validity of van’t Hoff’s assumption regarding the summationof the rotatory powers of several asymmetric atoms in a molecule,generally known as the ‘( principle of optical superposition.” Thetheoretical discussion and a criticism of the experimental evidenceadduced by Guye and Walden in support of the principle were givenin 1906 ; these authors find that, at looo,[ of Z-menthyl diacetyl-d-tartrate = - 226’.9, ,, -I- ,, = - 382’.[M j DAccording to the ‘‘ principle of optical superposition,” the rotationof the mesotartrate should be exactly the mean of the d- andZ-tartrates, whereas it differs by 24’ or nearly 10 per cent.fromthis mean.It must thereforebe admitted, in spite of the way in which similar views expressed byM. A. Rosanoff 10 have been criticised by Guye and Gautier,ll thatthe principle of optical superposition is not strictly true.The difference in solution is still more marked,Abstr., 1907, i, 896.Ibid., 1906, 89, 1884.I b i d , , 417.Trans., 1907, 91, 705.lo Abstr., 1907, ii, 207STEREOCHEMISTRY. 181It has usually been concluded from the available experimentalevidence that the introduction of an ethylene linking into anoptically active compound always increased the rotatory power ; thereverse was found to be the case for the change from propyl to allyl l2in active nitrogen compounds, and also in the allyl and prop91derivatives of tartramide l3 and malamide.14Hilditch l5 has adduced further evidence in support of the above-mentioned conclusion from his experiments on the rotatory powers ofthe menthyl and bornyl esters of phenylpropionic, cinnamic, andphenylpropiolic acids.It was found that the change \C*C/ -+ \C:C/produces anincrease in the rotatory power, whilst in the removal of another pair ofhydrogen atoms, the change\C:C/ -+ -CiC- caused a decreasein rotatory power, so that the rotatory power of the compound con-taining the acetylene linking now became less than that, of thesaturated compound.These results agree with those obtained by Walden for the I-amylesters of the same acids as far as the change from saturated to ethyleniclinking is concerned, but differ from them as regards the effect OF thechange from ethylenic to acetylenic linking.The rotatory power ofthe amyl ester of phenylpropiolic acid is intermediate between that ofthe cinnamate and the phenylpropionate. This work therefore furtheremphasises the impossibility of formulating general conclusions con-cerning a property which is so sensitive to small changes in severalfactors as optical rotatory power is found to be.The results of the first of a series of experiments carried out withthe object of investigating the possible connexion between theabsorption of light and optical rotatory power are described by A.W.Stewart Is; the particular point to which attention has been directedis the effect of the change from a saturated compound to one contain-ing an ethylene and then an acetylene linking.There is no connexion between the optical rotatory power and thepersistence of the absorption bands when these exist, but in the casesexamined there appears to be a relation between the extent of thegeneral absorption and the rotatory power which is stated as a rule6‘ greater rotation greater absorption.”This rule is shown to hold good in certain cases of closely-alliedcompounds, such as the three acids mentioned above, phenylpropionic,/ \ / \/ \l2 Thomas and Jones, Trans., 1906, 89, 310.13 Frankland and Twiss, ibid., 1855.14 Frankland and Done ibid., 1859.l5 Proe., 1907, 23, 287.Trans., 1907, 91, 199182 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.cinnamic, and phenylpropiolic acids and their amyl esters ; butyric andcrotonic acids and their amyl esters, and other similar cases. Thatthis rule, however, is only applicable within very narrow limits isshown by the fact that itaconic acid has a greater absorptive powerthan citraconic and mesaconic acids, whereas its amyl ester has arotatory power between those of the citraconate and mesaconate.It is clear also that the absorptive power of an acid cannot alwaysindicate the magnitude of the rot,atory power of its esters, since therotatory powers of the amyl esters of phenylpropionic, cinnamic, andphenylpropiolic acids examined by Walden do not bear the samereIation to one another as those OF the corresponding menthyl estersexamined by Hilditch.The effect of solvents on the rotatory power of non-electrolytes hasoccnpied the attention of several workers, and a great deal of work onthis subject has appeared.Winther17 has extended his investigations on the effect of solventson the rotatory power of active solutes, and now suggests a completetheoretical explanation of these effects.Ethyl tartrate is found to have a specific rotatory power of + 30.4’in solution in formamide a t infinite dilution and of - 19’ in ethylecedibromide under the same conditions ; these are respectively thehighest posit,ive and negative rotatory powers yet recorded for thissubstance.The molecular weight of the solute in formamide isnormal, whereas in ethylene dibromide the molecules of solute areassociated except in very dilute solutions, It is shown that in allsolvents except water and formamide, the rotation dispersion-coefficientof nicotine is independent of the solvent and of the concentration;the same is also shown for solutions of ethyl tartrate.Stress is laid on the part played by internal pressure in altering therotatory power-the internal pressure of a large number of solventsis calculated by the use of van der Waal’s equation and Amagat’sdata for the compressibility of the liquids.The author makes three fundamental propositions referring to theeffect of solution on active substances : (1) isothermal changes ofvolume in homogeneous systems are due to change of pressure(internal or external), to change of degree of association, dissociationor state of combination, or to the simultaneous action of two ofthese ;(2) Every alternation in the rotation of an optically active com-pound is causally related to a volume change;(3) Every volume change, which is due to change of pressure alone,is accompanied by a change of rotation proportional to the change ofvolume.l7 Abstr., 1907, ii, 831, 832STEREOCHEMISTRY.183Proposition (3) is shown to hold for solutions of nicotine in severalsolvents, including water, alcohols, ether, and benzene ; for camphor ina large number of very different solvents ; for &turpentine in severalsolvents, and for some metallic salts of camphoric acid in water.When the solvent and solute do not form compounds, then theinfluence of the former on the rot'ation of the active solute depends onthe difference in their internal pressures.On arranging solvents in theorder of the magnitude of their influence on the rotatory power ofactive solutes, the order is the same for different active solutes. Theinternal pressure of one liquid can be determined from measurementsof the specific gravities of solutions of different concentrations inanother liquid whose internal pressnre is known.It is concluded thatdiethyl tartrate has itlmost the same interns1 pressure as methylalcohol.According to this author, then, change of volume, whether caused bytemperature, change in degree of association, dissociation, or com-bination, or by change of pressure, is entirely responsible for theinfluence of different solvents on the rotatory powers of active solutes.Patterson has, during his long series of researches on the influence ofsolvents on the rotatory power of ethyl tartrate, repeatedly insisted onthe relation of theobserved effects to the molecular solution volume ofthe solute, and has again in a recent pnperIs emphaaised the quitesecondary part played by association in many cases.Winther also deals with the rotatory power of electrolytes inaqueous solution ; the volume of the active part of the electrolyte issaid to remain constant; during dissociation, and so the rotatory poweris not altered directly by the process of dissociation.The importance of the study of rotatory power as a met! od ofinvestigating solutions is pointed out, since this property is the onlyone which measures the changes of one only of the two constituents ofa solution.Many other workers have also contribut d to our knowledge ofoptical rotatory power of solutions ; Piritti and Magli 19 describe thedetermination of the rotatory power of the eight alkyl hydrogenaspartates containing respectively the methyl, ethyl, n- and iso-propyl,allgl, n- and isobutyl, and the isoamyl-groups. I n aqueous solution,these salts are all dextrorotatory a t low temperatures and hvo-rotatory at higher temperatures; the change is due to increasingdissociation as the temperature is raised ; the anion is Izevorotatory,and the corresponding sodium salts are laevorotatory at all tempera-tures between 10' and 90' with the exception of the isopropyl com-pound, which only becomes lzvorotatory above 2 2 O .The rotatory18 Patterson and Thomson, Abstr., 1907, ii, 322.l9 Abstr., 1907, i, 296184 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.power is proportional to the concentration of the solution. It isinteresting to note that the rotatory power of the ally1 compound isless than that of the Fropyl compound, and also that the rotatorypowers of isopropyl and isobutyl compounds are greater than those ofthe corresponding normal compounds.The rotatory power, however,does not chauge regularly with the weight of the alkyl group.The observations of Pribram 2O and of Shinn 21 indicate thatOudeman's law for electrolytes is not universally true, The last-mentioned observer has examined the rotatory powers of tartrates andof alkaloid salts in very dilute solutions, and concludes that hisresults cannot be hsrrnonised with the theory of electrolytic dis-sociation, since the rotatory power frequently does not tend t o attaina constant value and the changes observed in these aqueous solutionsare very similar to those observed for solutions of substances such asquinine oleate in chloroform.Sherry 22 has determined the rotatorypowers of a number of substance3, chiefly sugars and alkaloidsdissolved in liquid ammonia, liquid sulphur dioxide, or liquid methyl-amine. These results are interesting, since the solvents are sodifferent from those already examined, yet the rotatory powers ofthe solutes are often very little different from those observed inordinary solvents ; no mutarotation was observed, and, in ammoniaand methylamine, lzevulose gave no observable rotation.Patterson has continued his observations on the influence of solventson the rotatory power of ethyl tartrate, confining his attention toisomeric solvents or those differing but little in structure.I n a paper by Patterson and McMillan,23 the rotatory power ofethyl tartrate mixed with the two stereoisomeric (syn- and anti-)benzaldoximes is shown to differ to a remarkable extent.Therotatory power of a mixture of 90.11 per cent. of ethyl tartrate and9-89 per cent, of benzanti-aldoxime has a rotatory power of 11-38' ;this falls gradually to 8*1G0, the value for a mixture of the same con-centration with the syn-oxime. The observation of the change inrotatory power of an active substance can therefore be used toinvestigate the change of one dynamic isomeride with which it ismixed to another. The same is shown to be the case for mixturesof ethyl tartrate with th6 anisaldoximes and with ethyl formylphenyl-acetate.This surprising difference in the influence of two stereoisomerides onthe rotatory power of ethyl tartrate, a difference in the case of thetwo benzaldoximes greater than that between water and chloroform,led to the investigation by Patterson, Henderson, and Fairlie2* of theinfluence of ethyl maleate, fumarate, and succinate on the rotatory2o Abstr., 1907, ii, 207 21 Ibid., 417.zL Ibid., 920.2y Trans., 1907, 91, 504. $4 B i d . , 1838STEREOCHEMISTRY, 185power of ethyl tartrate. The specific rotatory power in maleic andfumaric esters is 13.4' and 13.27' respectively a t 20' in 20.67 percent. solution, whilst that in succinic ester is 9.35'. The molecularsolution volume of the esters is nearly the same in all three solvents.These results are surprising, since the difference between the maleateand fumarate is so small and yet the difference between the fumarateand succinate is greater than that between the diamyl esters of theseacids. It is suggested that these effects may be due to combinationof solvent and solute.This method of investigating changes in theconstitution of the solvent would therefore be applicable in a limitednumber of cases only, since in this case two stereoisomerides showpractically the same effect.A few interesting contributions to our knowledge of racemism andracemisation have also appeared during the year. Ladenhurg 25 hasre-examined the behaviour of the '( partially racemic " salt, brucinehydrogen racemate, which crystallises with 24 molecules of waterof crystallisation ; the d-tartrhte is anhydrous, and the Z-tartratecrystallises with 5 molecules of water of crystallisation.Below 44O,the racemate is less, and above 44' it is more, soluble than thetartrate mixture; hence the salt is only resolved by crystallisationabove 44Q. Neutral brucine racemate, however, is not resolved at anytemperature below 100'.Up to the present time, no melting-point curve of two substanceswhich form a partially racemic compound has been examined. Thislacuna has been filled by Findlag and Miss Hickrnaq26 who haveexamined the melting points of the Z-menthyl mandelates ; menthylr-mandelate is rz partially racemic compound, but undergoes dissociationinto its two constituents to the extent of about 50 per cent., which isindicated by the flattened summit of the curve drawn with meltingpoint as ordinate.A new criterion of racemism has been suggested by Stewart 27 onthe basis of his examination of the absorption spectra of active and ofexternally compensated compounds.d- and &Tartaric acids show the same absorptive power, which is lessthan that of racemic acid in concentrated solutions, but the same indilute solutions.Similarly, dipentene shows greater absorption thand- and 2-limonene.Difference in absorptive power of the active and externally com-pensated compounds may therefore be regarded as an indication thatthe latter is racemic; this method of detecting racemic compoundswill be of special value in its application to liquids. Bruhl28 alsopoints out that a difference in the refractive indices and magnetic2j Abstr., 1907, i, 586.Ibid., 1537.26 Trans., 1907, 91, 905.28 lbid., 115186 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.rotatory powers of the active and externally compensated compoundsindicates that the latter is racemic; this is found to be the case forA-a:s(s)-p-menthadiene.While collecting material for the study of the ‘‘ Walden inversion,”to which reference is made later in t h i s report, Fischer 29 observed aparticularly interesting case of racemisation.LEvorotatory iximethyl-a-propiobet aine, CH3*FH*?0, was prepared by the action of(CH,),N---Otrimethylamine on d-uIbromopropionic acid and also by the action ofmethyl iodide on d-alanine in alkaline solution.Now, by the action of trimethylamine on d-a-bromoprl)pionic ester,the additive compound, CH3*FH*N(CH3)3Br, containing a quin-CO;C,H5quevalent nitrogen atom, is formed readily at the ordinary temper-ature.This compound is, however, optically inactive and identical withthat obtained by the action of trimethylamine on i-u- bromopropionicester. By observing the rotatory power of the mixture during there:iction, it is found t h a t an active additive compound is first formedwhich can be isolated, and that the racemisation of this is due to thepreFence of excess of trimethylamine. d- Alanine ester, which owesits activity to a similar asymmetric carbon atom which is attached toa tervalent nitrogen atom, is not affected by trimethylamiue.This interesting case of racemisation is somewhat analogous to thatobserved by Pope and Harvey 30 in tetrahydro-/I-naphthylamine,CH,*yH,C6H4<CH2* CHON H,’when this is converted into an acyl derivatire or liberated from itssalts by alkali, and it is possible that a similar explanation to thatsuggested in this case may also serve to account for the behaviourof the compound of d-a-bromopropionic ester and trimethylamiue.The rather bewildering results obtained in the partial saponificationof Z-ment,hyl mandelaf e, in which a dextrorotatory acid was sometimesobtained, whilst in other experimekts the acid obtained was l ~ v o -rotatory, have been further investigated by A.McKenzie and H. A.Muller, 31 and the conditions determining the formation of the oneoptical isomeride or the other in excess have been clearly established.Z-Menthyl d-mandelate is saponified more readily than the Z-man-delate, so that, the d-acid should be present in excess in the acid obtainedby partial saponification of the ester.Racemisation of the acid alsooccurs simultaneously, but this is of secondary importance in thosecases in which a dextrorotatory acid is obtained.A dextrorotatory mandelic acid is o5tained when Z-menthgl29 Abstr., 1908, i, 80.31 Ibid., 1907, 91, 1814.Trans., 1901, 79, 83STEREOCHEMISTRY. 187r-mandelate is partially saponified by dilute caustic potash in the cold,owing to the rate of saponification of the d-mandelate being greaterthan that of the Z-mandelate and racemisation by the alkali beingreduced to a minimum when the alkali is dilute and cold,A lsvorotatory mandelic acid is produced when the same proportionsof ester and alkali are heated a t 100' in concentrated solution.Thisis due to the fact that, when saponification has prmeeded for sometime, there is excess of I-mandelate in the unchanged ester, and thepotassium mandelate already formed has been racemised by the actionof alkali ; the racemising action of the alkali, however, is uow rapidlydiminishing as the concentration of alkali in the solution diminishes,and eventually we have the lsvorotatory acid produced in excess fromthe ester containing excess of Z-mandelate and this acid retains itsactivity.In counexion with the subject of racemisation, it may be mentionedthat the allied process which takes place in menthone under theinfluence of catalysts in which one of the two asymmetric carbonatoms only is affected has now been very fully investigated byTubandt.82 This author has now followed the course of the changein a number of different solvents.H e concludes that the catalystforms an additive product with the carbonyl group of the menthone,and that this compound is formed more readily, and consequentlyinversion occurs more rapidly, the smaller the hydrolytic power of thesolvent.During the year, no method involving a new principle has beenadded to the methods available for resolving externally compensatedcompounds into their active constituents, but these methods havebeen used in the resolution of a number of substances and severalvery interesting modifications have been introduced.McKenzie and Thompson33 and McKenzie and Muller 34 show thatpure d- or Z-mandelic acids can be obtained from the mixture ofvmandelic acid and one of the optical isomerides, produced by partialsaponification of Z-menthyl or Z-bornyl uandelate by fractionalcrystallisation of the acid and its magnesium and cadmium salts fromwater.An improved method for the resolution of alcohols has been workedout by Pickard with Kenyon35 and Littlebury.36 The acid ester ofthe alcohol and a dibasic acid, phthalic acid was used, is separatedinto its two components by fractional crystallisation of a salt formedwith an active base, alkaloids or menthylamine were used, and libera-tion of the active alcohol by saponification.Saponification of these32 Abstr., 1907, ii, 670.33 Trans., 1907, 91, 789.s5 Trans., 1907, 91, 2058.34 L O C .eit.36 Ibid., 1973188 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.acid esters takes place readily, and this gives the method a furtheradvantage over the menthyl carbamate method (previously describedby these authors), since the carbamates are sometimes difficult tohydrolyse. This method has been used for the resolution of sec.-octylalcohol, in which case the menthyl carbamate method had failed toeffect resolution. The dextrorotatory alcohol was obtained from thebrucine salt of the acid phthalic ester, and the l~vorotatory alcoholfrom the corresponding cinchonidine salt.The method has also been used for the preparation of the fourisomeric borneols in a pure state.The constants of the pure com-pounds are given.Betti 38 has resolved r-a-aminobenzyl-/I-naphthol in an interestingway by fractional crystallisation of the compound,C6HIo0,:N*QH*C,H,C,,H,* OH’which the base forms with dextrose. The dextrose compound of thed-base is the less soluble, and from it the dextrorotatory base can beproduced readily by hydrolysis with dilute acid.Locquin 3s has succeeded in resolving a-amino-p-met hylvaleric acidby crystallising tho brucine salt of its formyl derivative, a methodpreviously used by Fischer and Warburg for leucine. a-Amino-p-methylvaleric acid is a particularly refractory compound, since it wasnot resolved by the crystallisation of the salts of five differentalkaloids with four of its derivatives.Pope and Beck 39 show by the resolution of tetrahydro-p- toluquin-aldine that another strong acid, the d-up-bromocamphorsulphonic acidof Armstrong and Lowry, may be added to the list of those availablefor the resolution of bases.H.0 Jones 40 has shown in the case of d- and Z-camphoroximes andd- and Z-camphor, using dextrorotatory turpentine oil and pure Z-amylbromide as solvents, that the solubility of optical isomerides in anoptically active solvent is the same, and also that their rotatory powersare the same in active solvents.Little progress has to be recorded in our knowledge of the spatialconfiguration of stereoisomerides, although a few important relation-ships have been established.Fischer 41 has answered Rosanoff’s 42 criticism of the method ofrepresenting optical isomerides by the prefixes d- and Z- without refer-ence to their rotatory power, which he proposed and which has been ingeneral use for such a long time.Rosanoff claims that Fischer’s system is rendered useless and mis-37 Abstr., 1907, i, 314.39 Trans., 1907, 91, 458.41 Ibzd., 148.38 Ibbid., 593.40 Abstr., 1907, ii, 237.42 Ann.Repoyt, 1906, 193STE REOCHEMISTRY. 189leading by the conversion of one compound, which is called d, intoanother compound, called I , as, for example, in the case of the trans-formation of d-glucuronic acid into I-xylose, and suggests variouschanges in the system of nomenclature.Fischer criticises these proposed changes adversely, but suggeststhat, to avoid confusion, d’ and I’ might be used when the prnfixedletter does not indicate the sign of the rotation of the compound ; thusglucose would be d-glucose, and lsvulose d’-fructose.Fischer and Jacobs 43 have fixed the spatial configuration of d-serinewith reference to that of d-glyceric acid, the configuration of whichhad been referred t o d-tartaric acid, and consequently to d-glucose, byNeuberg and Silbermann.Later, Fischer and Raske 44 succeeded in converting I-serine intod-alanine, so that the configuration of the latter is therefore deter-mined with reference to that of d-glucose, and, since d-alanjne can beconverted into d-lactic acid, the configuration of the latter is alsodetermined ; I-serine and d-alanine are the first of the amino-acidsthe configurations of which have been referred t o that of d-glucose.It is assumed that the reactions used are optically normal, and no‘‘ Walden inversion ” has taken place.The spatial configuraticns of these substances are represented thus :F O P T O P Q O P 702H FopCH,*OH CH,*OH CH,*OH CH3 CH3H-?-OH B,N*F-H H-F-NH, H2N-5?-H HO-7-HI-G 1 yceric Z-Serine d-Serine d- Alaninc d-Lacticacid (dex- (natural) (natural) acidThe changes which the guanidine compougds of the sugars undergoin aqueous solution have been very fully examined by Morreli andB e l l a r ~ .~ ~ The guanidine compounds of dextrose, lzevulose, and mannoseshow mutarotation in aqueous solution ; the rotatory power finallybecomes practically constant. The change is due t o the interconver-sion of the three sugars brought about by the guanidine until equili-brium is attained ; the changes are very similar to those caused byalkali hydroxides and investigated qualitatively by Lobry de Bruynand van Ekenstein, but the action of guanidine differs from that ofthe alkali hydroxides in that the side reactions in which acids andcoloured products are formed are much less pronounced.Each change was followed quantitatively with the polarimeter, andthe final state of equilibrium was determined by quantitative estima-troro tatory)4y Abstr., 1907, i, 393.44 Zbid., 900.45 Tyans., 1907, 91, 1010190 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRYtion of the sugars.by the following scheme :The changes which take place are best representedMannose ‘ Intermediate substance --+ Acids.The velocity constant for the change of mannose into laevulose is0*0005, and into dextrose 0.00036 ; the velocity constant for the trans-formation of dextrose into Iaevulose is 0.0015, and for the reverse change0.0021, all referring to 37”.The velocity of formation of mannosefrom dextrose is very small, and the velocity of formation of acids issmall.McKenzie and Wren 46 have succeeded in effecting an asymmetricsynthesis of tartaric acid ; Z-bornyl fumarate when oxidised yields aslightly kevorotatory acid ; a much more decided result is obtained byusing Z-bornyl hydrogen fumarate. Similar results are obtained byusing Z-menthol ; d-borneol yields a dextrorotatory tartaric acid.The most remarkable observation made in the domain of stereo-chemistry, since the observations of Pasteur served to found thisbranch of chemistry, is that of Walden 47 on the curious change of con-figuration which takes place during the interconversions of malic andchlorosuccinic acids and is known as the “ Walden inversion.”These observations on the changes which take place under the actionof reagents may bo summarised conveniently in the following scheme,in which are included also the observations of Tilden and Marshall 48on aspartic acid :+KOH$0” 3 Z-Chlorosuccinic acid -+ f-Pc15 td-Malic acid+PC15 +2-Aspartic acid ,lo, /’4 q Z-Malic acid +- d-Chlorosuccinic acid‘3.KOH +The changes under the successive action of phosphorus pentachlorideand silver oxide enable one to convert d-malic acid into Z-malic acid orvice versa.Walden came to the conclusion that the action of phosphorus penta-chloride and caustic potash was ‘6 optically normal ” or, in other words,that these reagents replaced the hydroxyl group by chlorine or viceversa without changing the spatial configuration of the groups aroundthe asymmetric carbon atom, and that the action of silver oxide was46 Trans., 1907, 91, 1215.47 Abstr., 1896, i, 205 ; 1898, i, 127, 178 ; 1899, ii, 53848 Tyans., 1895, 67, 494STEREOCHEMIYTRY.191optically abnormal. This conclusion is remarkable, since, from theknown influence of caustic potash in causing racemisation, one wouldhave expected this and not silver oxide to behave abnormally.Waldentried the effect of a large number of different metallic oxides and hydr-oxides, which he found, when arranged in order according to the amountof inversion caused by each, formed a series with caustic potash at oneend and silver oxide at the other, Walden was unable to use the corre-sponding esters, since these were saponified by caustic potash and werehardly affected by silver oxide. Which of the two reagents, nitrosylchloride or nitrous fumes, behaved abnormally was not settled.The problem practically remained as Walden left it until F i ~ c h e r , ~ ~during the course of his study of amino-acids, observed the followinginstance of a ‘( Walden inversion ” :d- Alanine (a-amino- NOBr Z-Bromopropionic acidpropionic acid) ---+ Ia st Z-Bromopropionic ._acid.NOBrt-- + Z- Alanine.Similar observations were also made on leucine and on phenylalanine.The reaction of ammonia with the halogen acids proceeds muchmore smoDthly and easily than the action of caustic alkalis, andcan be carried out by treatment with aqueous or liquid ammonia;further, the ester of the bromo-acid may be used instead of the acid.Some racemisation a1 ways occurs during the reactions.The conclusion is drawn that the action of ammonia is opticallynormal, and this is supported by later experiments on an analogousreaction of trimethylamine,50 which acts on d-a-bromopropionic acid togive laworotntory trimethyl-a-propiobetaine,CH3*C3f*Y0(CH,),N*O ’identical with that obtained by the action of methyl iodide ond-alanine in alkaline solution.The action of nitrosyl bromide on d-alanine ester proceeds smoothly,with the result that d-bromopropionic ester is formed.Similarresults were obtained with d-leucine ester and with Z-aspartic ester ;hence it follows that tht! action of nitrosyl bromide on the acid mustbe optically abnormal.Phosphorus pen tachloride yields products having the game con-figuration when it acts on a hydroxy-acid and when it acts on theester of the same acid; it is probable therefore that its action isoptically normal, but further evidence on this point is desirable, and49 Abstr., 1905, i, 692 ; 1906, i, 808.50 Ibid., 1908, i, 80.See also ibid., 1907, i, 192192 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.especially is it necessary to settle conclusively whether caustic potashor silver oxide is the abnormal reagent.Since esters are not available, as stated above, on account of thehydrolysing action of caustic potash, a bromo-polypeptide, a-bromo-propionylglycine, was used ; this, when treated with silver oxide,yielded a syrup which, after hydrolysis with dilute acid, gave lacticacid.The following observations then prove that the action ofsilver oxide is optically abnormal as stated by Walden :&Lactic acid. KOH I-Bromopropionic acid -+I-Bromopropionic acid -+I-a-Bromopropiony lglycine - - +AgaO d-Lactic ,,LLactic ,, AgzOand hydrolysisIt is also clear that the ‘( Walden inversion ” is dependent on thepresence of the carboxyl group, and, further, a comparison of thesechanges with the changes in configuration which sugars undergo underthe influence of alkalis, and sugar acids under the influence of pyridineor quinoline, would appear to justify the conclusion that it is only anasymmetric carbon atom in the a-position t o a n electronegative groupthat can undergo this inversion. Several other cases of the ‘( Waldeninversion ” are recorded in later papers on polypeptides.As regards the mechanism of this inversion, Fischer is inclined t oagree with Walden that the formation of intermediate products isresponsible for the change.An additive product of aspartic ester andbromine has been found to have the formula C,HI50,*NHBr,Br2;if a further additive product be formed from this compound andnitric oxide, from which the amino-group is eliminated and replaced by abromine atom, a possible method in which the ‘‘ Walden inversion” takesplace can be imagined.If, in this additive compound, it be assumedthat the bromine atom which is eventually to become attached to theasymmetric carbon atom is already within the sphere of influence ofthis carbon atom, then all that is necessary in order t o effect a “ Waldeninversion ” is that, when the amino-group is eliminated and replaced bybromine, the carboxyl group should slide into the position formerlyoccupied by the amino-group and that the bromine atom should takeits place. A similar scheme might be conceived for the action of silveroxide, and it is probable that the presence of a carboxyl group deter-mines the formation of these additive products.The results of the further investigation of these changes mill beawaited with considerable interest, since it is extremely probable that,through them, we shall acquire valuable information concerning themechanism of some chemical reactions and the internal structure ofchemical molecules.The problem of the origin of natural petroleum has again attracteSTEREOCHEMISTRY. 193attention, and valuable experimental evidence has been brought forwardby Neuberg 51 and by Letvkowitsch and Pick 52 in support of thehypothesis of Engler and Hofer that mineral oils have an organic origin.Neuberg 53 had shown that proteins on decomposition yield optic-ally active fatty acids, and now shows that, by the action of heat onthese acids, oils having all the characteristic properties of naturalpetroleum are produced.A mixture of oleic acid and d-valeric acidyielded an optically active petroleum when distilled or heated underpressure.Lemkowitsch and Pick show that chaulrnoogra oil, when distilledwith zinc dust, yields an optically active petroleum, so that fats as wellas proteins can give rise to optically active hydrocarbons.I n this connexion, it may be interesting to mention that Jones andWootton 5* found that petroleum from Borneo, which contains largequantities of aromatic hydrocarbons, is ltevorotatory, and that thisactivity is due both to the aromatic and to the other hydrocarbonspresent in the less volatile fractions.Some contributions to our knowledge of phenomena attributed tosteric hindrance have been made during the year.Kaufler suggests that the usual formulze for polycyclic compounds,such as diphenyl, and for conjugated ring systems, such as naphtha-lene, should be replaced by space formulsarepresenting the manner inwhich the planes of the different rings are inclined to one another.Aspaco formula for benzidine is given which, it is claimed, explains thedifficulty experienced in diazotising the second amino-group, andsimplifies the conception of the formation of benzidine from hydrazo-benzene. This suggested formula does not, however, appear veryprobable, and the difficulty referred to by Kaufler does not exist.Scholtz and Wassermann56 describe a number of cases in whichCH2*CH2>N*R, are formed from ae-di- CH,*CH2 pipericiine derivatives, CH,<bromopentane and nz- or p-substituted aromatic amines, whereaso-substituted amines yield derivatives of pentamethylenediamine,R*NH*[CH,],*NH*R.Hans AXeye~-;~ shows that, in the case of some esters of.substitutedciiichonic acids, the fact that methyl esters are often less stable thanethyl esters may outweigh the influence of steric hindrance, so thatmethyl esters in which steric hindrance is expected to occur can behydrolysed more readily than ethyl esters, in which there is no sterichindrance.5 l Abstr., 1907, i, 577, 997.53 Ibid., 1906, i, 923.55 Abstr., 1907, i, 307.57 Ibid., 342.REP. -x70L. Iv.53 Ibid., 997.54 Trans., 1907, 91, 1149.56 Ibid., 339.194 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Kauffmann and Pranck 58 describe a number of striking instancesof total absence of, or greatly diminished velocity of, reactions in-volving the group R in resorcinol derivatives of the type :K.ONewhereas substitutions in the nucleus take place readily ; the reactivityof the group R must therefore be greatly diminished by the sterichindrance of the two methoxyl groups,It is gratifying to note that Kipping's persistent efforts to establishthe ability of silicon to give rise to optical activity under the sameconditions as carbon have been rewarded with su~cess.5~ Greatexperimental difficulties have been encountered, since the silicon com-pounds examined so frequently behave in a quite unexpected maytowards reagents, and also because they appear to be exceptionallydifficult to resolve.Here one can only summarise the important factswhich justify the conclusion that an optically active silicon compoundhas been prepared.Phenylbenzylethylpropylsilicane, on treatment with sulphuric acid,yields benzene and a compound which is shown to be sulphobenzyl-ethylpropylsilicyl oxide : #7 8 3 5 7 2 %SO,H*C,H,*CH,*Si - 0 - Si*CH2*C6H,*S03H.I IC3H7 (33%Since two asymmetric silicon atoms are present, it is to be expectedthat the product formed would be a mixture of an externally com-pensated compound analogous to racemic acid and of an internally com-pensated compound analogous to mesotartaric acid ; one only of thesehas been isolated, which is shown to be the dl- or externally com-pensated compound.The salts of this acid with I-menthylamine, I-bornylamine, cinchon-idine, strychnine, and d-methylhydrindamine were prepared andexamined.I n the case of the salt of the last-mentioned base onlywas there conclusive evidence of resolution into two components onrecrystallisation. The two salts obtained have different meltingpoints, but show practically the same rotatory power in solution, andyet the sodium salts of the acids prepared from them show smallspecific rotatory powers of 3.3' and -4.5' respectively. The lesssoluble salt yields the dextrorotatory sodium salt,The enantiomorphoue relationship of the acids contained in the twod-methylhydrindamine salts is proved by examjning their behaviourtowards I-methylhydrindamine.Each of the two salts was first con-58 Abstr., 1907, i, 1092. Trans., 1907, 91, 209STEREOCHEMISTRY a 195verted into the ammonium salt, and this was treated with the hydro-chloride of Z-methylhydrindamine with the following results :Less soluble d-methylhydrindamine salt, m. p. 205' -+Z-methylhgdrindamine Ealt, m. p. 145'.MoresolubIed-methylhydrindamine salt, m. p. 1 35'(alightlyimpure) -+Z-methylhydrindamine salt, m. p. 205'.The enantiomorphous relationship of the acids is thus proved, not onlyby the opposite rotatory powers of their sodium salts, but also bytheir behaviour towards two enantiomorphously related bases, givingfour salts enantiomorphously related in pairs, thus : dBdA and ZBZA,melting at 205O, and dBZA and ZBdA, melting at 1 4 5 O .I n a later paper, the same authorG0 describes the preparation ofanother compound containing an asymmetric silicon atom, benzyl-methylethylpropylsilicane, which by treatment with chlorosulphonicacid is converted into a sulphonic acid.The salts of this acid withseven optically active bases have been examined, but hitherto noevidence of resolution has been obtained.A number of papers dealing with the optical activity of quinquevalentnitrogen compounds have appeared. Our knowledge of the principlesgoverning the isomerism of these compounds is gradually beingextended, and these principles are shown to be analogous to thosewhich apply to asymmetric carbon compounds,The autoracemisation of optically active ammonium halide s Jts inchloroform solution, first observed by Pope and Harvey,G1 who suggestedthat i t was due to partial dissociation of the salt into tertiary amineand alkyl halide, has again attracted attention.The phenomenon hasbeen observed in the oase of practically all the active nitrogen com-pounds which have been prepared; all these compounds contain anallyl or a benzyl group, or both.Goldschmidt G2 does not consider that the evidence in favom of thehypothesis that dissociation is responsible for the racemisation is con-clusive, and von Halban ''8 points out that considerable decompositionoccurs in a chloroform solution of ~~henylbenzylmethylzllylammoniumiodide. Wedekind,Gi however,shows that the decomposition i n the case ofthe corresponding compound containing the n-propyl instead of the allylgroup is but slight, and yet autoracemisation in t h i s case also proceedsrapidly in chloroform solution.The absence of extensive dissociation or decomposition in chloroformsolutions of these salts was proved by the molecular weight determina-tions carried out by Barger 65 on two iodides containing the benzyl6o Trans., 1907, 91, 717.64 lbid., 246.Ann.Report, 1906, 197.61 Ibid., 1901, 91, 828.63 Abstr., 1907, ii, 246.Trans., 1904, 85, 230.0 196 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.group attached to an asymmetric nitrogen atom, in. which the valuefound for the molecular weight in chloroform was almost normal atfirst, but diminished slightly to a constant value on standing for a longtime.The decomposition which occurs is therefore not extensive,The hypothesis that dissociation into tertiary amine and alkyl halide isresponsible for the autoracemisation of these salts received strongsupport from the experiments of the present writer 66 on the a- and p-phenyl benzylmethyl-Z-amylammonium iodides, in which it was foundthat both these iodides, one of which, a, was dextrorotatory and theother lzvorotatory, gradually attained the same dextrorotatory poweron standing in chloroform solution.Dissociation into alkyl halide and tertiary amine has now been shownto take place in the case of ammonium compounds containing one of theseven alkyl groups, methyl, ethyl, propyl (98- and iso), butyl (n- and iso),and isoamyl, as well as those containing the ally1 or benzyl group bythe experiments of Jones and Hill,G7 in which it is shown that themethyl group can replace each of the other groups in a quaternaryammonium salt when the latter is heated with uetliyl iodide.Scholtz and Wassermann ti8 have made further experiments provingthe close analogy between the behaviour of the asymmetric carbon andnitrogen a toms.2-Phenyl- 6-mo t hyl- 1 -ethyl piperidine, whic h containstwo asymmetric carbon atoms, has been combined with benzyl iodide,thus making the nitrogen atom also asymmetric. Two of tlie fourpossible active forms of this compound have been used, and each of thesegave two, a and p, forms of the ammonium iodide.That weak acids, like tartaric acid, can be used for the resolution ofoptically active ammonium salts has been shown by Miss Homer intho case of phenylbenzyl methylisopropylammonium hydrogen tartrate.This method has been applied by Jones 70 to the examination of thephenylbenzylmethylethylamrnonium and phenylmethylethylallyl-ammonium salts, which were found 71 to have rotatory powers verymuch smaller than those of the corresponding compounds containinghomologous alkyl groups instead of the ethyl group.Wedekind andProhlich 71 had already re-examined the first compound and obtaineda much higher value for its rotatory power than that previouslyassigned to it. It has now been found, by the resolution of the acidtartrate, that the phenylbenzylmethylethylammonium ion has amolecular rotatory power of about 28S0, a value approximating tothat of the corresponding ?a-propyl ion, 299'; in the same way, the6ti Tmns., 1905, 87, 135.G* Abstr., 1907, i, 340.70 Proc.Cumb. Phil. Soc., 1907, 14, 376.q1 Thomas and Jones, Tmns., 1906, 89, 280.n Ann. €deport, 1906, 197 j Abstr., 1907, i, 122.67 Ibid., 1907, 91, 2084.69 Ibid., 692STEREOCHEMISTRY. 197phenylmethylethylallylnmmonium ion is found to have a muchgreater rotatory power than that previously assigned to it.Frohlich and Wedekind 73 have_resolved phenylbenzylmethyl-r,-butyl-ammonium d-camphorsulphonnte, and found that the molecular rotatorypower of the ion is - 254', which is lower than that of the correspond-ing isobutyl compound, namely, 323'; the relation of the two butylcompounds is therefore similar to that of the normal and isopropylcompounds of the same series ([&I], 299' and 398' respectively).The iodide of the 7%-butyl compound has a molecular rotatory powerof - 319.6" in alcohol and - 346.1" in chloroform solution ; in chloro-form solution, autoracemisation of the iodide takes place much lessrapidly than in the cise of the corresponding isobutyl compound.Wedekind and Frohlich 74 have also examined and resolvedcompounds containing the anisole and phenetole groups.p-Ethoxy-phenylbenzylmethylallglammonium d-camphorsulphonate was partiallyresolved, and yielded an iodide with a specific rotatory power of+ 6-39' in chloroform.The corresponding p-ethoxy-compound was also resolved by meansof its camphorsulphonate, and the ion was found to have a molecularrotatory power of - 11.l0, and the iodide in chloroform solution had aspecific rotatory power of -6.65'.The low value of the rotatorypower of these compounds as compared with the corresponding phenylcompounds ([A!$) for ion = 166", and [aID for iodide in chloroform= 55.4') 75 is very remarkable.p - Et hoxypheny 1 benz ylmeth ylall ylammon ium iodide has also beenprepared in three different ways, namely, by the addition of methyl,ally], or benzyl iodide to the corresponding tertiary amine. Eachreaction proceeds normally and the three products are identical. Theconclusion that no stereoisomerides of inactive asymmetric nitrogencompounds can be formed in this way is further substantiated by theresults of these experiments.The isolation of optically active compounds owing their activity tothe asymmetry of a single nitrogen atom which forms part of a closedring has at last been effected by Buckney,7G the compounds beingallylkairolinium salts of the formula :73 Abstr., 1907, i, 512.75 Pope and Harvey, Tmn?., 1901, 79, 828.74 Ibicl., 409, 410.7(1 AbRtr., 1907, i, 722198 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.in which the asymmetric nitrogen forms part of a tetrahydroquinolinemolecule. The same compound has also been resolved by E. and0. Wedekind 77 in the same way, namely, by fractional crystallisationof the d-bromocamphorsulphonate. The salt ZBdA is the less soluble,and gives the molecular rotatory power of 196' ([MI,, for acid ion,270O) ; the dBdA salt does not appear to have been obtained in a purestate, although the last-named authors obtained a higher value for therotatory power of the basic ion in this salt than that obtained fromthe ZBdA salt.The iodide recovered from the ZBdA salt was found to be opticallyactive ([MID - 65O), and to undergo autoracemisation very readily.Buckney and Jones7S describe the examination of a number ofquinoline and tetrahydroquinoline derivatives which, according totheory, should be capPble of giving rise to optical activity ; in one caseonly, namely, the allylkairolinium compounds mentioned above, wasconclusive evidence of optical activity obtained. Altogether in thispaper, and in a former paper,79 eight tetrahydroquinoline derivativescontaining an asymmetric nitrogen atom have been examined and onlyone resolved; there seems to be no assignable reason for the fact thatmuch greater diDiculty is experienced in resolving these cyclic nitrogencompounds than the ordinary substituted ammonium compounds ofwhich so many have now been resolved into their optically activecomponents.H. 0. TONEB.57 Abstr., 1907, i, 1073. 78 T T ~ E S . , 1907, 91, 1821.79 Ibid., 1903, 83, 1415

ISSN:0365-6217    

DOI:10.1039/AR9070400177

出版商:RSC    

年代:1907

数据来源: RSC

摘要:

ANALYTICAL CHERilISTRY.THE fact that the function of the writer of this Report must, fromthe nature of the subject, be that of a judicious reporter ratherthan of a reviewer has been insisted upon in previous AnnualReports, and the difficulty of treating the subject of the progress inAnalytical Chemistry in the form of a connected narrative has beenpointed out. The field to be covered is a very large and ever-increas-ing one, and from some inquiries which he has made, the author isled to believe that the arrangement of the subject-matter, whichhe has adopted in past years, is perhaps the clearest and mostconvenient one for the reader. The work of the year will thereforebe dealt with as before, under the following headings :(1) Inorganic Chemistry, including electrochemical methods.(2) Organic Analysis.(3) Analysis of Foods and Drugs.(4) Toxicological Analysis.(5) Apparatus.The above subdivision of the subject is, of course, to some extentan arbitrary one, but it appears to permit of a more methodicaltreatment than any other with which the writer is acquainted.Inorganic Chemistry.I n connexion with the qualitative section of this branch, there arebut few communications which merit special reference.The detection of ferrocyanides, ferricyanides, and thiocyanates inthe presence of one another is not always easy, and an apparentlyuseful method which appears to be characterised by certainty anddelicacy has been proposed for this purpose by Browning andPalmer.1 This depends on the fact that the ferrocyanides can beseparated from the ferricyanides and from the thiocyanates byprecipitation with a salt of thorium, whilst the ferricyanides can inturn be separated from the thiocyanates by precipitation with a saltAbstr., 1907, ii, 721200 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.of cadmium. The main difficulty is in connexion with filtration,but the method has given good results in the writer’s hands.I n mineral analyses, it is frequently necessary t o test silica precipi-tates for the presence of small quantities of oxide of titanium, andEnecht2 has described a method based on the reduction of thetitanium oxide and the decolorising effect of the resulting solutionwhen added to a solution of Rochelle salt, coloured slightly withindigotin, or, better, with methylene-blue.The detection of sulphites in the presence of thiosulphates andthionates presents some difficulty, and a method proposed byVotoEek3 seems likely to be useful.It is based on the fact that,whilst normal sulphites destroy the colours of solutions of certaintriphenylmethane dyes, thiosulphates and di-, tri-, and tetra-thionates are without effect. The most suitable reagent consists ofa mixture of a solution of magenta with one of malachitegreen, andthe author states that as little as 0*00006 gram of sulphurous acid(as normal sulphite) can be detected.For the detection of traces of moisture in gases or liquids, W.Biltz 4 makes use of potassium lead iodide, an almost colourless salt.,which is readily decomposed by traces of water with separation ofyellow lead iodide.Test papers may be easily prepared with this re-agent, and constitute a convenient method of applying the reaction.Ehrenfeld 5 shows that the red precipitate sometimes obtainedon acidifying the ammonium carbonate solution, which hasbeen used for the separation of arsenic and tin in the ordinaryprocess of analysis, consists of arsenic disulphide, the reduction ofthe higher sulphides being readily effected by stannous chloride inacid solution.Pozzi-Escot 6 recommends for the detection of traces of nickel theuse of ammonium molybdate, which gives a green, crystalline pre-cipitate even in the presence of a considerable excess of cobalt.Tschugaeff? however, points out that this test is far less sensitivethan that based on the use of dimethylglyoxime, which is saidto be capable of detecting as little as one part of nickel in twomillion parts of water.The ionisation theory, which was, I believe, first put forward byOstwald to explain the colour changes manifested by indicators, hasbeen very generally accepted as correct, notwithstanding an impor-tant paper published some years ago by Eltieglitz,* who suggestedwhat he termed the ‘‘ chromophoric ” theory, pointing out that itwas more probable, for example, that phenolphthalein, in its colour-Abstr., 1907, ii, 654.a Ibid., 195. Ibid., 574.Ibid., 949. IbicZ., 818. Ibid., 989.Ibid.,1904, ii, 17ANALYTICAL CHEMISTRY. 201less solution, has the constitution of a lactone, whilst its salts arederivatives of a carboxylic acid containing the chromophoricquinonoid complex :C,H,:O.Following up his work on thecolorimetric measurement of affinity, Salm, in conjunction withFriedenthal, has recently published a paper 9 on this subject, inwhich he adduces some evidence for the beIief that the colourchanges of indicators are, in many cases, due rather to intramolecularchange than to ionisation. In this connexion, it may be mentionedthat Knowles 10 recommends alizarin-red I.W.S. (alizarinmonosul-phonic acid) for use in alkalimetry instead of methyl-orange, overwhich it appears to possess some advantages, and that 0. Stark11states that excellent results may be obtained with 3-amino-Z-methyl-quinoline as an indicator, especially in substitution f o r methyl-orange in the titration of ammonia.As a standard substance for usein alkalimetry and acidimetry, Phelps and Hubbard 12 recommendsuccinic acid, obtained by the hydrolysis of ethyl succinate.RonchBse 13 describes an ingenious method for the estimation ofammonia, based on the reaction of formaldehyde with ammoniumsalts, whereby hexamethylenetetramine is formed, and, if theformaldehyde is in sufficient excess, the whole of the acid of theammonium salt is liberated, and may be titrated with standardalkali.I n former reports, reference has been made to the estimationof sulphuric acid by Raschig’s benzidine method, and, as this methodis capable of giving good results and may occasionally be of use, itwould seem desirable to direct attention to a paper by Friedheimand Nydegger 14 on this subject.The authors have fully investi-gated the most favourable conditions for precipitation, and give fullparticulars in regard to the solubility correction.The ‘‘ nitron ” method for the gravimetric estimation of nitricacid has been submitted to a detailed and critical study by S. W.Col1ins,l5 who finds that good results can be obtained both withsimple and niixed pure nitrates and in commercial products, suchas natural waters and nitratecontaining fertilisers. In view of theexpense of the “nitron,” it is satisfactory to note that the authorhas succeeded in devising a process for the recovery of the base.Last year, Jannasch and Heimann 16 succeeded in quantitativeIyvolatilising phosphoric acid from its salts by making an intimatemixture of the phosphate with carbon, and distilling off the, phos-phoric acid in a stream of chlorine.This method, although itgave good results with ammonium hydrogen phosphate and withAbstr., 1907, ii, 389. lo B i d . , 389. l1 fiaid., i, 974.l2 &d., ii, 297. l3 Ibid., 651. l4 Ihid., 196.j 5 Ibid., 907. l6 Bid., 1006, ii, 745202 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.ammonium magnesium phosphate, was somewhat clumsy and diffi-cult to carry out. Jannasch and 3ilke17 have now improved onthis, in that the phosphoric acid is distilled off by heating stronglyin a stream of chlorine mixed with the vapour of carbon tetra-chloride. The results given for ammonium phosphate and for mag-nesium phosphate are very good, and the method is one which might,in cerbain cases, be usefully employed in mineral analysis.Thetime required for the carrying out of the process (between four andfive hours for the vaporisation of an amount of phosphoric acid equi-valent to about 0.3 gram of magnesium pyrophosphate) would, how-ever, constitute a drawback from the point of view of practicallaboratory procedure.The quantitative separation of the halogens constitutes a veryimportant analytical problem, and one t o the solution of which agreat many chemists have a t various times devoted themselves. Theprinciple underlying almost all existing methods is that of differen-tial oxidation, and, as the ‘( oxidation potential ” of all the oxidisingagents recommended is, with one exception, higher than that of anaqueous solution of chlorine, it follows that good results can onlybe obtained by accurately interrupting the process when the wholeof the bromine has been distilled over, and by paying minute atten-tion t o the experimental conditions, especially to the degree ofacidity and concentration.Iodic acid constitutes the single excep-tion referred to above, and was originally proposed for the separa-tion of bromine and chlorine by Bugarszky.18 This substance hasan “ oxidation potential ” which lies between that of chlorine, andthat of bromine, and, consequently, it is well suited for the separa-tion of these two halogens. The method, which does not appear t obe so widely known as it should be, has been submitted to it furtherstudy by Andrews,lg who has suggested certain improvements in theprocedure, and has shown, not only that accurate results can beobtained in the separation of bromides and chlorides, but that themethod is applicable to the estimation of chlorine in crude bromine.For the estimation of cyanogen in slightly dissociated salts, suchas mercuric cyanide, mercuric cyanonitrate, and mercuric cyano-chloride, Borelli20 has proposed a method in which the cyanogen isobtained in the form of sodium cyanide by treatment with alumin-ium powder in a solution rendered strongly alkaline with sodiumhydroxide.The results appear t o be good, and the process, whichis also applicable to the determination of cyanogen in complexiron cyanides, is more rapid of execution than that of Rose.Agood many methods have a t various times been proposed for the17 dbslr., 1907, ii, 564.ly Ibid., 1007, ii, 503.Ibid., 1896, ii, 216.2o ]bid., 825ANALYTICAL CHEMISTRY. 203analysis of mixtures of thiocyanates and chlorides, or bromides, andRosanoff and Hill 21 have studied and criticised some of these, andhave devised a method which appears to be both simple and rapidof execution. This depends on the oxidation of the thiocyanate tohydrocyanic acid by means of nitric acid, and is similar to oneproposed years ago by Volhard, but differs from that in that thesolution is not rendered alkaline, a treatment which, according toRosanoff and Hill, causes the re-formation of some thiocyanate.The separation of tellurium from certain heavy metals and itsaccurate estimation has occupied the attention of Brauner andKuzma,22 who show that, when tellurium in the presence of copper,bismuth, and antimony is precipitated by means of sulphur dioxide,appreciable quantities of the associated metals are carried down,and that this is especially the case with copper.I n order t o over-come this difficulty, the authors recommend the oxidation of thetellurium to telluric acid by means of ammonium persulphate, andthe subsequent precipitation of the heavy metals with hydrogensulphide. The tellurium can then be estimated by reduction withhydrochloric acid and sulphur dioxide. Incidentally, attention iscalled t o the interesting fact that, when solutions containing bothcopper and tellurium are oxidised with the persulphate, an intensered coloration is observed, which the authors attribute t o the forma-tion of a, derivative of cupric acid.Hinrichsen23 calls attention to the great difficulty there is incompletely removing the hydrofluoric acid when that substance hasbeen used in conjunction with sulphuric acid for the decompositionof silicates.He points out that, when ammonia is subsequentlyadded for the purpose of precipitating the iron and aluminium, adouble fluoride of ammonium and aluminium is formed, which issoluble in hot water, and he states that this behaviour may be thecause of introducing a very serious error into the aluminium esti-mation.This paper deserves the attention of all who are interestedin mineral analysis. The estimation of iron, aluminium, and titan-ium, when present together, is a problem of very frequent occur-rence in mineral analysis, and two papers dealing with this subjectwill be read with interest. One by Gallo24 deals especially with thevolumetric estimation of the titanium by titration with a solutionof ferric alum, whilst in the other, by Magri and Ercolini,25 amethod for the electrolytic separation of the iron is described.I n this connexion, attention may be directed t o a paper by Goochand Newton,26 who show that iron may be determined by titrationwith permanganate in the presence of titanium if some bismuth24 Ibid., 402. 25 Ibid., 400.3(i Ibid., 507.Abstr., 1907, ii, 984. 22 Ibid., 716. 23 lbid., 506204 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.oxide is added to the reduced solution. This appears to have theeffect of oxidising the titanium without affecting the ferrous salt, sothat the latter may be directly titrated after filtration. Inasmuchas the authors specially recommend the use of amalgamated zincfor the reduction of the iron, the writer of this Report. may perhapsbe permitted once again to direct the attention of analysts to thegreat advantage of using charged palladium for that purpose. I fthe metal is fully charged, reduction is readily brought about, andthere is obviously nothing to interfere with the sharpness of the endreaction with the indicator. The quantitative separation of zincand cadmium by means of hydrogen sulphide is, as is well known,somewhat troublesome, inasmuch as the acidity limits within whichsuch separation can be effected are very narrow, and in any caseseveral precipitations are usually necessary. Box 27 has shown thattrichloroacetic acid may be advantageously substituted for themineral acids usually employed in this separation, and that, unlessthe amount of zinc present is large in relation to that of.thecadmium, a single precipitation is sufficient. A critical paper byFunk,28 dealing with a kindred subject, namely, the separation ofzinc from nickel, cobalt, iron, and manganese by means of hydrogensulphide, is worthy of study, in view of the well-known difficultiesattaching to the problem.The author recommends either precipi-tation from a solution containing formate or Treadwell’s process,in which the precipitation is effected in the presence of an excessof an alkaline chloride or sulphate.Glixelli 29 contributes a very interesting communication dealingwith the theory of the action of hydrogen snlphide on zinc salts, andshows that, contrary to the generally accepted view, the reactionZnS0,+H2S=ZnS+H2S0, is not a reversible one, but that falseequilibria occur in acid solutions which are sometimes very per-sistent, and which can be upset, and precipitation hastened, by thepresence of zinc, cadmium, or copper sulphides. The author is ofopinion that the separation of zinc from nickel and cobalt in acidsolutions by means of hydrogen sulphide does not depend on thedifference in the equilibrium conditions, but on the inductionperiods.There is still considerable room for investigation in connexionwith the methods for estimating and separating many of the rareelements, and the results of such investigations are always welcome.This is the case with a paper by Paal and Arnberger,30 who havedevoted a good deal of attention to the analytical chemistry ofosmium.Although this rare element is of some technical import-27 Trans., r907, 91, 964.lbid., 868.28 Ahstr., 1907, ii, 398.3o ]bid., 404ANALYTICAL CHEMISTRY. 205ance, the methods recommended for its estimation do not appear tohave been well worked out, and leave much to be desired in pointof definiteness and accuracy.Of these, perhaps the most widelyknown is that in which the osmium is separated as Fr6my’s osmyldi-ammine chloride from alkaline osmate solutions. The abovemen-tioned authors have now shown that this method is very unsatis-factory, and have suggested several processes which will doubtlessbe carefully tested by those analysts who are actively interested inthe analytical chemistry of the platinum metals. In this connexion,it may be noted that Makowka31 has shown that osmium is com-pletely separated from acid solutions by acetylene, and he also statesthat palladium in acid solution may be precipitated and separatedfrom platinum and iridium by means of the same reagent. Thoseinterested in this method may also be referred t o two papers on thesame subject by Erdmann and Makowka.32Dittrich and Freund 32a have studied the separation of thorium,titanium, and zirconium from iron, and have devised a new methodfor separating titanium from zirconium.This consists in adding adilute and faintly acid solution containing these elements to a boil-ing solution of ammonium salicylate. Zirconium salicylate is pre-cipitated, the titanium remaining in solution. Small quantities ofthe latter element may be carried down with the zirconium, butcomplete separation may in such cases be effected by a second pre-cipitation.As an interesting example of the manner in which organic com-pounds are being pressed into the service of analytical chemistry,mention may be made of the use of dicyanodiamide sulphate as aprecipitant for nickel.This substance, the use of which had pre-viously been suggested for the detection of nickel, has now beenapplied by Grossmann and Schiick 33 to its estimation. The dicyano-diamide precipitate may be converted into nickel sulphate, orapparently more accurate results are obtained by drying a t 1 1 5 O andweighing, the precipitate then having the compositionNi( C,H,ON,),.Cobalt in the tervalent condition and zinc are not precipitated, andthe method may be used for the separation of nickel from iron andfrom aluminium. Similarly, Brunck 34 has employed dimethyl-glyoxime, which had previously been suggested as a test for nickel,for the estimation of that metal, and its separation from certainother metals, such as zinc, manganese, iron, aluminium, andchromium. The results appear to be good, and the method is rapid,31 dbstr., 1907, ii, 403.32a Ibid., 1908, ii, 134.32 Ibid., 399, 403.33 l b i d ., 1907, ii, 582, 819.34 Ibid., 582, 989206 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.but the costliness of the reagent must tend considerably t o restrictits useAlthough there is little that is new in a paper by Kolb and Feld-hofen,35 these authors have done good service in calling attention tothe fact that hydrogen peroxide may, under suitable conditions, beused for the purpose of reducing mercuric salts t o the mercurousstate. The best conditions for obtaining the mercurous chlorideprior to its estimation by Hempel’s well-known iodine method aregiven.The detection of very small quantities of mercury in explosiveshas recently become a matter of some practical importance, owingto the marked manner in which minute quantities of mercuricchloride affect the Abel heat test.A satisfactory spectroscopicalmethod for this purpose was devised by the late Dr. Dupr6, and, ina recent paper, Hargreaves and Rowe 36 have described an electro-lytic process, the mercury being deposited on a gold foil cathode,from which it can be obtained by sublimation in the form of globulesfor microscopical identification.The ‘‘ comparison of mirrors ” method for the estimation of minutetraces of arsenic, which was first suggested by Sanger, has beenextended by that author and Gibson37 to the estimation of verysmall amounts of antimony.It has been found that, when quanti-ties less than 0.1 milligram of that element are added to the reduc-tion flask under the conditions laid down by the authors, the wholeis evolved as hydride. The Gutzeit,although distinctly inferior for most purposes to the Marsh-Berzeliusmethod, has its uses, and Sanger and Black38 have dealt a t con-siderable length with the former process, and have made a detailedstudy of the conditions which must be observed if the greatestdegree of sensitiveness and accuracy is to be obtained. Robertsonand Nbpper 39 have dovised a method for the estimation of smallquantities of nitrogen peroxide which is specially applicable to theexamination of the gaseous products of the decomposition of gun-cotton and other explosives.This is based on a comparison ofthe absorption spectrum of the gas under observation with that ofa standard gaseous mixture, the spectrum of nitrogen peroxidebeing, as is well known, very characteristic, and altering markedlywith the concentration.The test results are good.ElectTolytic Methods.A good deal of very useful work has been done during the year inthe study of electrochemical methods of analysis.35 Abstr., 1908, ii, 69.37 Abstr., 1907, ii, 654.a6 J. SOC. Chem. Ind., 1907, 26, 813.3y Trcu~., 1907, 91, 761. 38 Ibid., 1908, ii, 65ANALYTICAL CHEMISTRY. 207Dorniaar 4O has investigated the cause of the high results whichare frequently obtained in the electrolytic estimation of antimony,and finds that, whilst they are partly due, as has usually been sup-posed, to the inclusion of sulphur compounds in the precipitate,they are chiefly due to oxidation changes inherent in the electrolyticprocess itself.The same conclusion has been arrived at by Foersterand Wolf,41 who have identified antimony oxide as well as sulphurin the precipitated antimony. Foerster, Blankenberg, Brunner,Lee, and Rommler have made a detailed study of the influence oftemperature on the electrolytic deposition of various metals, andsome of their results are of importance. Thus it has been observedthat, whilst a t the ordinary temperature the decomposition poten-tials of zinc and nickel are so near to one another that electrolyticseparation is impossible, the difference is so greatly increased a thigher temperatures that a satisfactory separation can be effected.Other advantages appear to result in special cases from working a televated temperatures.The advantages of employing rotating electrodes are now wellrecognised.With these, it is possible to work with much highercurrent densities, whilst the time required for the deposition of themetal to be determined is very much shortened, and the deposit is,moreover, frequently obtained in a better form for weighing. Avery important paper, and one embodying a considerable amount ofvery useful work, has been published by H. J. S. Sand,42 who de-scribes the results he has obtained working with rotating electrodesand employing graded potential.The test results are, as a rule, verygood, and the electrolytic separation of no fewer than seven metals inone solution must surely constitute a record. Miss Langness 43 alsodetails the results she has obtained in a number of estimations andseparations when working with a rotating anode, and the paper isone which may be read with advantage. From the point of viewof analytical chemistry, perhaps the most important, and certainlythe most useful, electrochemical investigations are those undertakenwith the object of ascertaining the precise working conditions neces-sary for the accurate separation of commonly associated metals.The above-mentioned papers afford instances of this class of com-munication, and, as another example, attention may be drawn toa paper by Miss Kollock and E.F. who have determinedthe time necessary for the complete deposition of a number of metalswhen varying amounts of sulphuric acid were present in the elec-trolyte, a ‘mercury cathode and a rotating anode being employed.Results are also given showing the best experimental conditions for41 Ibid., 508. 40 ABslr., 1907, ii, 200. 41 Tyans., 1907, 91, 373,43 Absty., 1907, ii, 585. 44 ]bid., 719208 ANNUAL lCEPORTS ON THE PROGRESS OF CHEMISTRY.effecting certain separations. Another interesting communicationis that of Hildebrand,45 who shows that the negative radicles in suchcompounds as the carbonates, thiocyanates, and ferrocyanides of thealkali and alkaline earth metals may be estimated by employinga cell with a mercury cathode and a rotating silvered platinumanode.This work has been extended by McCutcheon, jun.,lG byLukens and E. F. Smith,47 and by McCutcheon, jun., and E. F.Smith.48 These authors have observed that, when solutions ofmetallic chlorides are electrolysed according to Hildebrand's method,the metals are capable of being divided into two classes, accordingto the behaviour of the amalgams formed. Thus the amalgams oflithium, sodium, potassium, calcium (see below), strontium, andbarium decompose in the outer, or cathode, compartment withformation of the corresponding hydroxides, whilst the amalgams ofmagnesium, aluminium, and the heavy metals are decomposed withformation of the corresponding hydroxides in the inner, or anode,compartment.It was therefore possible in this way to carry outelectrolytically a number of interesting separations. It is note-worthy that in the electrolysis of solutions containing both mag-nesium and calcium chlorides, none of the latter metal passes intothe outer compartment, as is the case when calcium chloride aloneis used. It would appear therefore that on this behaviour an in-teresting method might be based for the electrolytic separation ofcalcium from barium and strontium. In order to obviate the neces-sity for using a motor for the purpose of rotating the electrodes,Frary49 has adopted the device of causing the electrolyte itselfto rotate by placing it within a solenoid, through which the currentused for the electrolysis passes.The conditions affecting the accu-racy of the results obtained in the electrolytic estimation of leadhave been somewhat exhaustively studied by Vortmann,6O who showsthat good results are not so easily obtained as is often imagined,and that there are a good many substances which interfere, and inthe presence of which special treatment becomes necessary. It iswell known that the ease with which many oxidation and reductionchanges can be effected-depends very greatly on the nature of themetal of which the electro,de concerned is constructed. This pheno-menon, usually referred to as " supertension " or " over-voltage," hasbeen ascribed by Tafel, Caspari, and others to the pressure a t whichthe hydrogen and oxygen respectively are set free at the surfaces.Kauflertl however, contends that it is largely, if not entirely, dueto local heating of the electrodes, and haa shown that a low " poten-45 Abstr., 1907, ii, 574.48 Ibid., 988.@ Ibid., 988.49 lbbid., 649.61 Ibid., 924.47 lbid.) 988.6o Ibid., 302ANALYTICAL CHEMISTRY.209tial " metal, such as platinum, is capable of bringing about changeswhich can usually be effected only by high (' potential " metals ifsuitable means are taken t o heat the electrode sufficiently.Organic Analysis.Reactions (chiefly dependent on colour changes) of more or lesscomplicated organic substances, even when characteristic, are, as arule, of very little general interest, but reference may perhaps bemade to communications dealing with some analytical reactions ofveronal (diethylmalonylcarbamide) by Lemaire,52 and of maretineby the same author,53 of adrenaline by Krullt4 of vesipirin (phenyl-acetosalicylate) by Zernik,55 and of antipyrine by Steensma,"6 asthese substances are of therapeutic importance.A simple reactionof adrenaline, which is said to be characteristic, is also described byGunn and Harrison.57 Molinari 58 has investigated the use of ozoneas a reagent for the study of the unsaturatedness of organic com-pounds. The author finds that unsaturated compounds, whetheraliphatic o r aromatic, containing double bonds combine readily withozone, whilst aliphatic compounds containing triple bonds, althoughuniting directly with a large proportion of iodine, do not absorbozone.F o r the detection of small quantities of hydrocyanic acid,Thigry 59 recommends the use of test papers, moistened first with adilute solution of copper sulphate, and then with an alkaline solu-tion of phthalophenone. I n the presence of hydrocyanic acid, afairly permanent rose-red coloration is produced, and the test issaid to be capable of detecting the presence of as little as one partof hydrocyanic acid in two million parts. The separation of dye-stuffs in mixtures is often a matter of considerable difficulty, andthe suggestion of E. LehmannGO that advantage may sometimes betaken of the different rates of diffusion into jellies is noteworthy.With a mixture of eosin and tartrazin, f o r instance, sufficientseparation could be effected to permit of certain identification.Avery comprehensive paper dealing with the identification of dye-stuffs on vegetable fibres by Green, Yeoman, Jones, Stephens, andHaley6l cannot fail t o be of great assistance, not only to colourchemists, but also to those whose incursions into this difficult fieldof analysis are of less frequent occurrence.W. E. Marshall 62 confirms the value of the p-dimethylaminobenz-Rep. Phawn., 1907, 19, 104. 63 Zbid., 49.55 Apoth. Zeit., 1907, 22, 152.57 Ibid., 591.@2 Abstr., 1907, ii, 996.61 dbatr., 1907, ii, 316.56 Abstr., 1907, ii, 995.58 IEid., i, 1039.REP.-VOL. IV. P59 lbid., ii, 408. Go lbbid., 234.J. Xoc. Dyers, 1907, 23, 252210 ANNUAL REPORTS ON THE PROGRESS OF CIIEXlSTltP.aldehyde test for indole, and shows that i t is capable of distinguisli-ing that substance from others giving very similar general reactions,and that it can, moreover, be employed quantitatively as a chlori-metric method.As I have already referred in previous reports63 t o Denn-stedt’s method of elementary analysis, it is well that attentionshould be called t o a paper by Baumert,64 who describes certainmodifications which he has introduced into this combustion process.In this connexion, reference may also be made to two papers dealingwith the relative advantages of platinum and palladium as contactsubstances in organic analysis, the one by A.Jacobsen and Lan-de~en,~5 and the other by Dennstedt.66 The latter author is ofopinion that platinum is for several reasons to be preferred to palla-dium, and points out that, although both these substances give betterresults with methane than oxide of copper, neither is capable ofbringing about the complete oxidation of that gas.Quite a numberof new methods for the estimation of halogens in organic compoundshas been suggested during recent years, some of which are bothrapid and exact, and the analyst is no longer compelled t o choosebetween the somewhat dangerous method of Carius and the trouble-some Iime-combustion process. Chablay, for instanceF7 describesa convenient and apparently accurate method, in which advantageis taken of the fact that halogen-containing organic compoundsreact with sodammonium with quantitative formation of the sodiumhalide, F o r the estimation of phosphorus and sulphur in organiccompounds by the fusion method, Stutaer 68 recommends the use ofbasic calcium nitrate, since this substance not only supplies thealkali necessary to prevent any loss of the elements in question, butalso melts below looo, and does not exhibit any tendency to detonateor spirt.For the estimation of hydrogen in a very large numberof organic and inorganic compounds, Lidoff recommends a volu-metric method involving the ignition of the compound with mag-nesium or aluminium powder. The results appear t o be good, andsulphur, nitrogen, and the halogens may be determined in theignited residue by the usual methods. It will be remembered thata few years ago, Hibbert and Sudborough 7^ showed that, by observ-ing certain precautions, Grignard’s magnesium alkyl halide method,which had been proposed by Tschugaeff for the detection of hydroxylgroups, might be made quantitative, and they published it numberof results in support of this contention.This method has now been63 Ann. Report, 1905, 195 ; 1906, 211.65 Ibid., 718. Ibid., 909.67 Ibid., 195. G8 Ibid., 906.69 Ibbid., 574. 70 Trans., 1904, 85, 933.Abstr., 1907, ii, 909ANALYTICAL CHEMISTRY. 211further examined a t Tschugaeff’s request by Zerewitinoff,7l who hasobtained very satisfactory results with a considerable number oforganic compounds, differing widely in their chemical characters,and there can be no ‘doubt that the method is a very useful one.The writer of this Report, in conjunction with Whitteridge,72 hasdevised a method for the estimation of tartaric acid which may beusefully employed in many cases in which the ordinary potassiumhydrogen tartrate method is, for various reasons, inapplicable.Thetartaric acid is precipitated as a basic bismuth tartrate, which isdissolved in acid, and determined volumetrically by titration withpermanganate. Lasserre 73 calls attention to a convenient methodof separating formic and acetic acids, on the one hand, from butyricand valeric acids, on the other, based on the fact that the two last-mentioned acids can be extracted from their aqueous solutions bymeans of benzene or toluene. Propionic acid cannot be separated inthis way, as it is equally soluble in benzene, toluene, and water.I f , asappears t o be the case, this separation is sharp, the metho,d is likelyto be much used. I n previous Reports,74 attention was called tothe employment by Knecht, and subsequently by obhers, of titaniumtrichloride as a reducing agent for use in chemical analysis. It hasan even more powerful reducing action than stannous chloride, andmay be used for the estimation, not only of such substances asferric iron, but also for the determination of organic nitro-com-pounds, such as trinitrocresol, dinitrobenzene, and dinitronaphtha-lene, as well as of azo-dyes, such as benzopurpurin. In a recentpaper, Knecht and Miss Hibbert75 describe the results of furtherwork in this direction, and show that in many cases where directtitration with the titanium trichloride gives inaccurate results, goodresults can be obtained by adding an excess and titrating back witha standard ferric solution.The authors also recommend the useof this reagent for the evaluation of commercial hyposulphites andfor the estimation of dissolved oxygen in water. One advantage ofthe titanium over the permanganate method in the latter estima-tion is that i t is not affected by any organic matters which may bepresent. This paper is one which will well repay study, especiallyby those chemists who are interested in the analysis of organicdyestuffs. I n my previous Report,76 I called attention to a paperby Valenta, in which he recommended the use of methyl sulphatefor the purpose of distinguishing between aromatic and paraffinhydrocarbons and separating them.This method has since beenstudied by Graefke,77 who has shown that aliphatic hydrocarbons are71 dbstr., 1907, ii, 509.74 Ann. Report, 1905, 195 ; 1906, 207.T2 Zbid., 513. 73 Ibid., 991.75 Abstr., 1907, ii, 907.Ann. Xeport, 1906, 214. 77 Chem. rev. E%tt.-€€arz.-Ind., 1907, 14, 112.P 212 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.not by any means completely insoluble in methyl sulphate, and thatin separations their solubility is oftten still further increased by thepresence of the dissolved coal-tar hydrocarbons. Notwithstandingthis, the method is, in certain cases, capable of being usefully em-ployed.Of all the problems in organic analytical chemistry, perhaps oneof the most difficult consists in the quantitative analysis of certaincomplex artificial carbohydrate mixtures.Indirect methods havealmost invariably to be employed, and errors in the estimation ofsome of the substances present, although not serious in themselves,are sometimes apt to become additive, and to fall with very seriouseffect upon the estimation of some one constituent. During recentyears, there has been an increasing tendency on the part of analyststo avail themselves of biological methods, and the application ofpure cultures of yeasts and other lowly organisms has rendered itpossible successfully t o attack analytical problems which had pre-viously been regarded as incapable of solution. The method isclearly one which must be applied with very great caution, anddemands a certain amount of biological training on the part of theoperator.Among others, Lindner has done a great deal of workin this direction, and atten€ion may be called to an interesting paperby Konig and €€ormann,78 in which some very useful confirmatorywork is recorded, and which contains the results of experimentsmade for the purpose of ascertaining to what extent the dextrinsobtained by the limited action on starch of acids and of diastaserespectively may be separated from the sugars. It is pointed outinter alia that the dextrinous body present in honey is of an entirelydifferent character from the dextrins prepared as above mentioned.This paper will well repay careful perusal by all who are activelyinterested in carbohydrate analysis.It is interesting to note thattwo species of torulz are capable of effecting a separation of dextroseand fructose from sucrose, and it seems very probable that a furtherstudy of the torulze (as opposed t o the true yeasts) might beproductive of useful results. Neuberg79 has shown that, by theaction of emulsin, raffinose is hydrolysed into a mixture of saccharoseand &galactose, and, in conjunction with Marx,gO has suggested theuse of emulsin as a test f o r the presence of raffinose in raw canesugars. I n view of the fact that the melting points of the osazonesare frequently made use of for purposes of identification, a paperby Tutinsl is of considerable importance. The author shows thatwhen d-phenylglucosazone is purified by recrystallisation from amixture of pyridine and alcohol, the compound melts at 2 1 7 O .TheA b s t ~ . , 1907, ii, 202.IDitl. ii, 408.7'3 ]bid., i, 388.a PYOC., 1907, 23, 250ANALYTICAL CHEMISTRY. 213melting point of 205O, which mas originally given by E. Fischer andthe correctness of which has always been assumed, must thereforeapparently be abandoned. It may be recalled that the meltingpoint of a-acrosazone has already been found t o be 2 1 7 O , instead of205O as originally stated, and it will be interesting to ascertainwhether similar differences will be observed in the case of the osazonesof other sugars. The nature of the influence exerted by basic leadacetate on the rotation of sucrose in aqueous solution has been in-vestigated by Bates and Blake,82 who show that von Lippmann’sstatement that basic acet’ate is without effect is incorrect.Theauthors find that on the progressive addition of the acetate thereis first a lowering of the rotation, and then a gradual rise, whichthey ascribe to the formation of soluble lead sucrates having rota-tions differing from that of sucrose itself. Lintner83 describes apolarimetric method for the estimation of starch in cereals, whichhas been further examined by Canet and D~rieux,84 who haverecorded a number of results with cereals and other starch-containingproducts. The method certainly appears to be capable of givinggood results, and will doubtless be useful as a substitute for themore lengthy and laborious diastase conversion method when rapidresults are required.The analysis of indigo has, during recent years, been made thesubject of a considerable amount of experimental work, and hasfurnished a good deal of controversy.The attention of all chemists who are interested in this matteris directed to an important communication by Orchardson, Wood,and W.P. BloxamJs5 constituting the second part of their paper on“ The Analysis of Indigo.” This contains an account of experimentsmade for the purpose of isolating the impurities present in cakeindigo, and of ascertaining how these substances behave with theanalytical reagents employed, and t o what extent they interfere.A new method is described for the estimation of indigotin obtain-able from the leaf, and the authors appear t o be confirmed in theiropinion that the separation of the indigotin in the form of a purifiedcompound (potassium indigotintetrasulphonate) must constitute thefirst step in the analytical process.The method of Bergtheil andBriggs, which was referred t o in my previous Report,*6 is adverselycriticised by the authors, who state that it gives irregular rmults.The attention of those interested in this matter may be also directedt o two other communications, one by Bergtheil and Briggs?7 andthe other by Gaunt, Thomas, and BIoxam,8* both dealing with the82 Abstr,, 1907, ii, 406,84 BuEL SOC. Chim. BeZg., 1907, 21, 329.@q dwz, Report, 1906, 216. 11’ Abstr. 1907, ii, 416. a8 &d., 1908, ii, 76.Ibid., 823.85 Abstr., 1907, ii, 203214 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRYestimation of indigotin in the plant The writer of this Report,in common with several other chemipts, has had an opportunityof witnessing a demonstration of the tetrasulphonate process, andin his opinion there can be no doubt that the indigotin is quanti-tatively separated from the impurities with which it is associatedin the crude product, and that, t o say the least of it, the processmarks a great advance.The estimation of choline and other bases in vegetable and otherextracts is a matter of considerable importance t o the physiologicalchemist, and any improvement in the methods for separating andestimating these substances is welcomed by a large and increasingbody of workers.Stankk’s periodide method for the separation ofcholine and betaine, to which reference was made in the lastReportFg appeared t o constitute a very useful addition to existingmethods, but Kiesel90 has shown that it cannot be applied to theestimation of choline in such materials as plant extracts, since thesecontain many other bases which seriously interfere with the accuracyof the results.During the past few years, rubber experts have shown a growingtendency to attach importance t o the results of chemical analysiswhen forming an opinion as t o the value of commercial rubbers.A t the present time, the most important constituent, caoutchouc,is almost invariably estimated by difference, and the desirability ofobtaining a direct method for its estimation is obvious.Severalsuch methods have been suggested, but by far the most promisingare those in which the rubber is submitted to the action of nitrousfumes, and the resulting so-called “ nitrosate ’’ weighed. I n a pre-vious Report,91 it was mentioned that Harries and Alexander hadfound that the nitrogen compound originally obtained by Weberwas not a t all definite. I n a recent communication, Alexander92has recorded the results of further work in this direction, and hassuggested a method which, if carefully carried out, would appearto be capable of giving fair results. Much work remains t o be donebefore i t can be said that a satisfactory process for the direct estima-tion of caoutchouc has been devised, but Alexander’s method appearst o offer a solid foundation for further building, and his results,moreover, may throw a good deal of light on the constitution ofcaoutchouc and on the nature of vulcanisation.Another promising direct method is that of Budde, which is basedon the readiness with which caoutchouc unites with bromine to forman insoluble tetrabromide.A carbon tetrachloride solution, con-taining both bromine and iodine, is added t o a solution of the89 Ann. Report, 1906, 220.Dl Ann, Report, 1005, 200,00 Abstr., 1907, ii, 994.AQatr., 1007, i, 433ANALYTICAL CHEMISTRY. 215rubber, also in carbon tetrachloride, and the tetrabromide, which isprecipitated by the addition of alcohol, is collected, washed, dried,and weighed. Budde has shown that the compounds formed bythe action of bromine on certain unsaturated rubber resins aresoluble in the above mixture of carbon tetrachloride and alcohol,and, consequently, do n o t interfere with the results.Two papers,the one by Budde,g3 and the other by Aselrod,94 have recently beenpublished, from which it would appear that this method, with slightmodifications, is applicable t o the direct determination of caoutchoucin certain vulcanised rubbers. The further development of thesetwo direct methods will be watched with very considerable interestby all who are concerned in the analysis and commercial evaluationof rubber.Analysis of Foods and Drugs.Comparatively little progress has been made during the year inconnexion with the analysis of milk and milk products. Analystsare well aware that the accurate estimation of fat in certain milkpreparations is not always an easy matter, and that differentmethods are required in dealing with various materials.Hals andKlykkeng5 have recorded the results they have obtained in theestimation of f a t in sweetened and unsweetened condensed milks bya number of standard prpcesses, and are of opinion that the Gottlieband the Gerber methods are the most accurate for the purpose.Cocliran g6 has investigated the behaviour of Wiley’s acid mercuricnitrate solution, and has shown that it has no effect on the polarisa-tion of lactose, and that a t temperatures below 1 5 O its invertingaction on sucrose is very slight indeed. I n these circumstances,it can be used with good results for the estimation of lactoseand sucrose in sweetened condensed milk. Although a good dealof attention ha$, been devoted during the year to the importantquestion of the detection and estimation of cocoanut oil in butter,the subject has not h e n very much advanced, and there can belittle doubt that the Polenske method (either as originally publishedo r modified) and the phytosterol acetate test combined are stillcapable of furnishing the most trustworthy indications.Referenceshould, however, be made t o a communication by Hinks,Q7 who hasproposed a direct qualitative test for the presence of the cocoanutoil. This is a micro-crystallographic method, and in the hands ofits author has given distinct indications when the cocoanut oil waspresent only t o the extent of 5 per cent.This method appears t obe useful, and t?he advantage of possessing a characteristic test f o r93 Gzcmni. Zeit., 1907, 21, 1205.Qj Zcitsch. Nahr. Gentcssm., 1907, 13, 338.94 ]bid., 1229.96 Absk.., 1607, ii, 586.97 Analyst, 190’1, 32, 160216 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.this troublesome adulterant will be apparent. Most analysts knowhow greatly the distillation conditions may affect the Reichert-Meissl,and especially the Polenske, values of fats, and Goske 9* has devotedsome attention to the influence of the mode of heating on thePolenske number. This paper may be read with advantage, if onlyto emphasise the importance of adhering strictly t o a standard setof conditions.In view of the importance to analysts of the phyto-sterol acetate test, a paper on this subject by Jaeger 99 is deservingof attention. Windaus and Hauth 1 showed that Calabar beanscontained two isomeric phytosterols having very different meltingpoints, and it is probable that other isomerides exist. Jaeger showsthat the melting point curves for mixtures of cholesteryl acetate,with the acetates of the two above-mentioned isomerides, affordevidence that the melting points of such mixtures are not a t alltrustworthy criteria of composition, and it is clear that the indica-tions of the test must be interpreted with considerable caution.While dealing with this subject, attention may be drawn to a paperby Lewkowitsch3 on the determination of paraffin in the unsaponi-fiable matter from animal fats.The author confirms the accuracyof Polenske’s method: and shows that good results can be obtainedby determining the saponification value of the mixture of the ace-tates and the paraffin. The esterification of fats and oils by themethod of Haller, to which the objectionable name “ alcoholysis ”has been given, has been applied with slight modification by Hanui 5to the detection of cocoanut oil in butter, and the recorded resultsindicate that the method may a t least serve as a useful auxiliaryone. Further work on the ‘‘ silver ” process of Wijsman and Reijsthas confirmed the view that the results are untrustworthy, and thatthe values do not afford any certain criterion of the purity of butterfat.It should be noted that Siegfeld 6 and others have shown thatthe feeding of cattle with cocoanut cake and beetroot leaves mayappreciably affect the Polenske and iodine values of the butter.Several chemists, including Kreis and Canzoneri, have endeavouredt o isolate the constituent of sesame oil which produces the redcoloration with furfuraldehyde and hydrochloric acid, but withoutcomplete success. Malagnini and Armanni7 appear t o have beenmore fortunate, inasmuch as they have separated a crystalline sub-stance, melting a t 67O, having the formula C7H603, which gives,with the abovementioned reagents, a very intense coloration. Theauthors regard this substance as a methylene ester of hydroxy-Og Zeitsch. Nahr. Gertussm., 1907, 13, 491.3 Chdm.Rev. Fett, Earz, Ind., 1907, 14, 51.Abstr., 1907, ii, 315.Abstr., 1905, ii, 8701fiid., i, 129. B i d .Zeitacit, Nahr. Crenussm., 1907, 13, 18. Ibids, 613s ’ G’hemi &it., 1907, 81, 884ANALYTICAL CHEMISTRY. 217quinol, and point out that it does not exist as such in the oil, butis formed from a more complex compound (which they have alsoisolated) by the action of dilute mineral acid. This reaction forsesame oil is a very important one, especially in view of the factthat in several countries sesame oil is compulsorily added to mar-garine for the purpose of earmarking that substance and of facili-tating its recognition in butter. The literature of this test isvoluminous, and much has been written as to the conditions whichaffect the sensitiveness of the reaction.Although samples of sesameoil which do not yield the red coloration are undoubtedly veryrare,* it cannot be overlooked that several observers, including Weig-mann and Soltsien, have recorded cases in which the reaction couldnot be obtained, and it is also well known that samples of sesameoil differ very widely in the intensity of the coloration which theyproduce. Lauffs and Huismanng have been working on this sub-ject, and have recorded another instance of a rancid sample whichfailed t o respond to the test. T'hese authors appear t o be of opinionthat this is due t o the formation of a condensation product of thesesamol with the aldehydic substance present in the rancid oil, andthey recommend the addition of a proportion of cottonseed oil t othe fat t o be tested, which is said to prevent the interfering effectof rancidity and t o render the test more sensitive.However thismay be, it is clear that this question requires further study, for inview of these recorded observations chemists are not justified inconsidering a negative result when applying the Baudouin test asa conclusive proof of the absence of sesame oil.The estimation of tartaric acid in the presence of malic and suc-cinic acids is a frequently recurring problem in the analysis of food-stuffs and other products, and chemists will no doubt criticallyexamine a method recommended by von Ferentzy.10 This is basedon the insolubility of basic magnesium tartrate in aqueous alcoholof 50 per cent.strength, and the ready solubility in that solvent ofthe corresponding salts of malic and succinic acids. Two otherpapers dealing with the same subject which are worthy of attentionare by Jorgensenll and by Kunz and Adam.12 Some interestingwork has been recorded during the year by T. B. Wood13 in con-nexion with the important question of the " strength '' of wheat flour.Perhaps the most noteworthy observations are those from whichi t is sought €0 show that the strength of flour is largely conditioned8 Lewkowitsch, i n a private communication to the writer of this Report, sbtesthat he has never yet met with a sample which failed in this respect, although hehas examined many which were old and undoubtedly rancid.Chem, Zeit., 1007, 81, 1023,Ibidr, 312,lo Abstr., 1907, ii, 991,la Zeitscb.anal. Chem., 1907, 40, 261,la d b 8 h ) 1907, ii, 810, and J, Agric A'ci~, 1907, 2, 139218 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.by the ratio of protein t o mineral matter, small quantities of certainsalts having, as is well known, an appreciable effect on the physicalproperties of the proteins. The extension of this work will bewatched with interest. The estimation of creatine and creatininein meat and other extracts has attracted the attention of severalchemists during the past year. Baur and Barschall l4 appear t ohave been the first t o apply the colorimetric method of Jaff6 (basedon the red coloration produced when picric acid is added to analkaline solution containing creatinine) to the examination of meatextracts, and their results were subsequently extended by Grindleyand Woods.15 Hehner16 has shown that in applying this methodi t is necessary t o ensure the presence of an excess of picric acid, andto match the coloration in as strong solutions as possible in orderto avoid the errors produced by the dissociation of the colouredcompound. The method affords a valuable means of distinguishingbetween extracts of meat and extracts made from yeast, since thelatter are practically devoid of either creatine or creatinine.It isperhaps worthy of note that extract of crab is also, according t oAckermann and Kutscher,17 free from those bases. Winton andBailey 18 point out that meat which has undergone even slight decom-position yields volatile sulphur compounds when distilled with phos-phoric acid, as in the ordinary estimation of sulphites.These areoxidised by bromine water, and so lead to an over-estimation of anysulphurous acid present. A method for obviating this difficultyis proposed, and the matter is deserving of the attention of foodchemists, as it may apply to other subst'ances than meat, and isespecially of importance in countries like the United States ofAmerica, where the presence of sulphites in food-stuffs is regardedso seriously. Woodman and Talbot l9 call attention to the presenceof fluorine as a very general constituent of malt, and consequently ofmalt liquors, and suggests one part in one hundred thousand as amaximum limit for fluorine normally present.For distinguishingbetween natural and artificial colouring matters in wines, Jean andFrabot 2o recommend warming with formaldehyde and hydrochloricacid, and the subsequent addition of ammonia. A colourless filtrateis said to be obtained with all natural wines. Of a number ofpapers which have been published dealing with the analysis ofpotable spirits, reference need only be made to one by Bedford andJenks21 on the estimation of the higher alcohols. These authorsare probably correct in stating that, whilst t'he results obtained byl4 Arb. Kaisl Gesun,dhcitsnmt, 24, 562.l6 Pharm. J., 1907, 78, 683.' 8 J. Amw. Chena. Soc., 1007, 29, 1499.l.5 Abstr., 1907, ii, 187.l7 Abstr., 1907, ii, 283.Ibid., 1362.ao Abstr., 1907, ii, 320.31 Jbid., 405ANALYTICAL CHEMTSTRY. 219the Allen-Marquardt process are good in the case of amyl alcohol,the intermediate alcohols, such as butyl and propyl, largely escapedetermination, and it is obvious that isopropyl alcohol cannot beestimated a t all. The method they propose resembles that ofBeckmann, in that the alcohols are extracted by carbon tetra-chloride, and then converted into nitrous esters. Instead, however,of estimating these by oxidation with permanganate, the authorstreat them with potassium iodide, and determine the liberatediodine. This communication is worthy of attention, but theauthors' claim to distinguish between amyl alcohol, on the one hand,and propyl and butyl, on the other, will scarcely be admitted byanalysts generally.Many papers have been published during the year describing newalkaloidal reactions (usually colour reactions), but these are scarcelyof sufficient importance to merit special reference.An exceptionmay, perhaps, be made in favour of two papers by ReichardF2 whodescribes somes new reactions of scopolamine and yohimbine.Knorr23 appears to have been the first t o suggest the use of picro-lonic acid (4-nitro-l-p-nitrophenyl-3-methyl-5-pyrazolone) as a preci-pitant for alkaloids ; Warren and Weiss 24 have experimentedwith this substance, and find that it is a more delicate test thanpicric acid for coniine, strychnine, and morphine, and Mattbes and.Rammstedt 25 have applied this reagent t o the assay of nux vomica,hydrastis, and jaborandi, and their galenical preparations.Theresults appear, as a rule, to be good, and the method is likely t o beuseful. The same authors26 have also obtained good results whenusing this reagent in the estimation of narcotine, codeine, and mor-phine. Tschirch and Edner 27 have investigated the constituents ofEnglish and' French rhubarb, and have shown that a diazotisedp-nitroaniline solution constitutes a useful reagent for the evaluationof that drug. The results when working with pure emodin wereaccurate, and the method appears t o mark a distinct advance on thecolorimetric process. It may be pointed out that the found per-centages of hydroxymethylanthraquinones (expressed for conveni-ence in terms of chrysophanol) range from 4.24 per cent.in the caseof the Shanghai t o 1.58 per cent. in the case of the Frenchproduct.Bougault28 has shown that the reagent (a solution of hypophos-phorous acid in hydrochloric acid) which he previously recom-mended for the detection of cacodylic and methylarsonic acids isapplicable t o the detection and estimation of arrhenal (disodium23 Abstr., 1907, ii, 915.26 Ibid., ii, 592.23 B i d . , 1897, i, 314. 24 Ibid., 1907, i, 869.26 Ibid., 1908, ii, 75.27 h3id,, 1907, ii, 501, 525. T&bz'Cl., 828220 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.methylarsonate) and atosyl (sodium anilinoarsonate). The authorfinds that the black substance which is produced when the above-mentioned reagent is allowed t o act on arrhenal has the formula(MeAs) and that it is quantitatively oxidised by nitric acid or byiodine to methylarsonic acid in accordance with the equation:MeAs + 41 + 3H20 = MeAsO(OTi),+4HI.The atoxyl compound issimilarly oxidised, and may be estimated in the same way. The sameauthor 29 finds that methylarsine di-iodide and oxide may be esti-mated by titrating their aqueous solutions with a solution of iodinein potassium iodide.Toxicological Analysis.Calvi and MalacarneM show that alcohol materially retards thedecomposition of cyanides, so that hydrocyanic acid may be detectedin organs which have been preserved in alcohol, even a t the end ofsome considerable time. Schaefer 31 has investigated the naturaloccurrence of arsenic in the human body, and has detected veryappreciable traces in the hair, skin, liver, kidneys, brain, and thyroidglands, and has thus confirmed the conclusion arrived at by otherworkers that arsenic in traces must be considered a ' I normal "constituent of the human organism.He expresses the opinion thatthe arsenic is localised largely in the nucleins, a suggestion whichseems t o find some support in the marked readiness with which theyeast cell takes up small amounts of arsenic. These results, support-ing as they do those already arrived a t by W. Thomson and others,appear t o indicate that no special significance can be attached t othe discovery of traces of arsenic in many of the organs of the body.Bolland and Franzos,32 in an investigation of two cases of phos-phorus poisoning, where the bodies had been buried for four months,found that it was impossible to obtain any definite indications ofthe presence of phosphorus by either the Mitscherlich or the Dusart-Blondlot method. During recent years, the guaiacum test f o r oxy-haemoglobin has been studied by a number of investigators, especi-ally with reference to the production of the coloration by othersubstances than blood.Bolland33 finds that the presence of tracesof iron in the solvents which are ordinarily employed in the treat-ment of blood stains gives rise to the well-known blue colour, butthat this is inhibited by citric acid. I n the presence, however, ofoxyhEmoglobin, the blue coloration is obtained, citric acid notwith-standing. Buckmaster,s4 dealing with the same subject, points outthat the reaction is due to the iron of the haemoglobin, iron-freederivativeg of that substance, such as hamatoporphyrin, failing toAbstr., 1907, ii, 916, Eo Ibid,, 409.Ibid., 371,34 Ibid.9 60Q1 sz Chcnz, Bitaj 190'1, 31, 8, 83 Absfr,, lQO9, ii, §GOANALYTICAL CHEMISTRY. 221give it. I n confirmation of this, Lesser35 finds that the blood ofinvertebrates, which contains no hzmoglobin, does not give thereaction. The benzidine test for blood proposed by Schlesinger andHolst has been investigated by Utz,3G who finds that it is moredelicate than the guaiacum reaction, provided that the reagents arefreshly prepared. Van Rijn,37 in the course of a study of the distri-bution of morphine in the animal organism, administered 200 milli-grams of the hydrochloride t o an animal, which was killed six hourslater.By the ordinary process of extraction, about 84 per cent.of the total amount administered was recovered, and the authorshows that the alkaloid tended t o accumulate very largely in theurine.A ppuratus.The following list contains reference only to those new pieces ofapparatus which have been described in recognised journals, andwhich appear to be of real utility. The titles are not alwaysexactly those given by the authors, but have been, in some cases,more or less altered in order to indicate more clearly the nature oftho apparatus in question.- In connexion with apparatus, it may be mentioned that Heraeus 38has shown by direct experiment that hydrogen from the flame of aBunsen burner diffuses through platinum, and may bring about thereduction of ferric oxide and other reducible substances. Theseexperiments throw a good deal of light on the corrosion and ultimatedestruction of platinum crucibles.‘( The Eennicott-Sargent Colorimeter ” (Cheem. Engineer, 1907,5, 213).“ A portable milk colorimet,er.” A.Bernstein (Chem. Zeit., 1907,31, 727).“ New melting point thermometer.” G. Muller (Chem. Zeit.,1907, 31, 571).(‘ New apparatus f o r determining melting points.” J. Thiele(Abstr., 1907, ii, 330).“ A calorimeter for volatile liquid fuels.” W. H. Rawles ( J . SOC.Cl~ein. Ind., 1907, 26, 665).“ A new portable gas generator.” A. W. Browne and M. J.Brown (Abstr., 1907, ii, 678).‘‘ A constant pressure gas generator.” A.W. Browne and M. J.Brown (Abstr., 1907, ii, 679).(‘ New gas-generating apparatus.” E. Steiger ( A bstr., 1907, ii,339).3B Absts.., 1907, ii, 827. 3G Ibid., 916. 37 Ibid., 995.38 Ibid., 969222 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.“ New gas-generating apparatus.” A. Burger and M. W. Neufeld‘( New apparatus for gas analysis.” 0. Pfeiffer (Abstr., 1907, ii,(‘ A gas-developing apparatus.” A. Kleine (Abstr., 1907, ii, 446).(( An improved gas generator.” F. Southerden (Chem. News,1907, 95, 207).(( Apparatus for crystallising and filtering in indifferent gases.”W. Steinkopf (Abstr., 1907, ii, 161).‘I A new absorption and washing apparatus f o r gases.” B. Phyl(Zeitsch. a n d . Chem., 1907, 46, 150).( I New absorption vessels for elementary analysis.” 0.Carrasco(Ckem. Zeit., 1907, 31, 342).(‘New form of potash bulb.” P. Malherbe (,4nn. Chim. anal.,1907, 12, 318).( ( Drying apparatus for elementary analysis.” 0. Mittelbach(Chem. Zeit., 1907, 31, 551).(( Simple apparatus, with stirrer, for treating a liquid a t itsboiling point with two or more gases.” N. L. Gebhard (Proc., 1907,23, 34).(‘ Boiling and distillation of foaming liquids.” R. Fanto (Zeitsclt.angew. Chem., 1907, 20, 1233).Two fractionating columns for readily volatile liquids.” H.Schlemmer (Chern. Zeit., 1907, 31, 692).(‘ Apparatus for distillation and desiccation a t low temperatures.”D’Arsonval and Bordas (Ann. Chim.. anal., 1907, 12, 4).(‘ Modifications of Dennstedt’s method of combustion analysis.”R.Baumert (,4bstr., 1907, ii, 909).(( Platinum resistance furnace for melting points and cornbus-tions.”(( A simple fat extraction apparatus.” G. S. Fraps (Abstr., 1907,ii, 314).‘(New extractor for the determination of fat by means of carbontetrachloride.” F. Vollrath ( A bstr., 1907, ii, 514).‘ I An improved fat extraction apparatus.” J. van Leeuwen(Chem. Zeit., 1907, 31, 350).“Extractor for use with small quantities of material.” C. L.Jackson and J. E. Zanetti (Abstr., 1907, ii, 859).((A new eudiometer for use in the analysis of mixtures of airand inflammable gases.”(( Some new ureometers.” M. E. Pozzi-Escot (,4bstr., 1907, ii,414; compare Albert Garcia, Abstr., 1907, ii, 994).( ( Modification of Regnard’s ureometer.” M.E. Pozzi-Escot(Abstr., 1907, ii, 724).(Ahstr., 1907, ii, 339).194).S. A. Tucker (Abstr., 1907, ii, 842).J. Meunier (Abstr., 1907, ii, 989)ANALYTICAL CHEMISTRY. 223“ Standardisation of Engler’s Viscosimeter ” (Zeitsch. angew.‘ I A modified Engler viscosimeter.” L. TTbbelohde (Ch em. Zpit.,“ A new filter paper of cotton cellulose ” (Chem. Zeit., 1907, 31,“ A simple arrangement for the filtration of alkaline liquids (in“ Pressure filter for laboratory use ’’ (Chem. Tracle J., 1907, 41,‘’ A new sublimation apparatus.” V. Schworzoff (‘4 b s f r . , 1907,” A self-filling burette.”‘‘ Burette reading.”If Arrangement for reading thermometers, burettes, &c.” L. H.Zeller (Chem. Zeit., 1907, 31, 115).“ Water-jet blower of very simple ~onstruction.’~ S.M. Revingtonand I. G. Rankin (Abstr., 1908, ii, 30).“ A convenient air-bath and hot-plate.” E. D. Campbell ( A bstr.,1907, ii, 446).“Asbestos wire gauze.” €1. Carliczek (Ckem. Zed., 1907, 31,500).“ Simple lamp for monochromatic light.” E. Beckmann (Abstr.,1907, ii, 209).‘‘ A new centrifugal apparatus for laboratory use.” T. Eorner(Abstr., 1907, ii, 161).Improved Liebig’s condenser.” H. R. Ellis ( A bstr., 1907, ii,“Some new forms of apparatus.” W. M. Dehn ( A b s t ~ . , 1907,“ Portable photometer.” J. A. Evans ( J . Amer. Chem. Soc., 1907,‘‘ A mercury joint in place of cork or rubber in organic analysis.”“Device for filling bottles from carboys.” R. M. Hughes and“The use of nickel crucibles in quantitative analysis, and theR.Kriiian (Abstr.,‘‘ Apparatus for absorbing acid vapours given off during the assay‘‘ Apparatus for obtaining standard temperatures in dryingChem,, 1907, 20, 832).1907, 31, 38).465).air free from carbon dioxide).305).ii, 160).R. Rinne (Abstr., 1907, ii, 447).N. J. Lane (Abstr., 1907, ii, 390).P. Kusnetzoff (nbs.fr., 1907, ii, 809).160).ii, 755).29, 1009).J. Marek (Abstr., 1907, ii, 909).C. Barrow ( J . Amer. Chem. SOC., 1907, 29, 241).composition of the so-called ‘‘ Nickel Soot.”1907, ii, 390).of gold, silver, &c.” Dard (Abstr., 1908, ii, 72).ovens.” J. Habermann (-4 bstr., 1908, ii, 17)224 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.‘ I Collodion membranes for dialysis.” S. L. Bigelow and A. Gem-bcrling (Abstr., 1907, ii, 933).“ Simple apparatus for analytical purposes.” J. McC. Sanders(Proc., 1907, 23, 232).New mercury-drop tensimeters.” W. M. Dehn ( J . Amer. Chem.Soc., 1907, 29, 1052).“Method of obtaining the flame spectrum of metals.” G. A.Hemsalech and C. de Watteville (Chem. Zed., 1907, 31, 693).‘I An automatic vacuum regulator.” A. E. Andrews (Chem. News,1907, 96, 76).“ A simple means for the recognition of the colour of small quan-tities of faintly-coloured liquids, and its use in microchemicalanalysis.” F. Emich and J. Donau (Abstr., 1907, ii, 809).“ Apparatus for the estimation of carbon dioxide in carbonates.”P. Malherbe (Abstr., 1907, ii, 719).‘( Apparatus for the supply of carbon dioxide in the determina-tion of nitrogen in organic compounds by the absolute method.”G. Young and B. Caudwell (Abstr., 1907, ii, 394).Apparatus for use in testing substances for phosphorus.” J.Habermann (Abstr., 1908, ii, 17).‘( Apparatus for the continuous preparation of pure oxygen foruse in organic analysis.” A. Seyewetz and L. Poizat (Abstr., 1907,ii, 162).“Improved form of apparatus for the rapid estimation of sul-phates and salts of barium.” W. R. Lang and T. B. Allen (Proc.,‘‘ Apparatus for the estimation of sulphur (in iron).” VonNostitz and Jankendorf ( A bstr., 1907, ii, 393).“ New laboratory method for the preparation of hydrogen sul-phide.”“ Apparatus for the gasonietric determination of hydrogen per-oxide.” W. M. Dehn (Abstr., 1907, ii, 906).“ Apparatus for determining the coefficients of expansion of oilswhich solidify a t low temperatures (crude petroleum).” J. Gruszkie-wicz and W. Bartoszewicz (Petroleum, 1907, 2, 525).“ Electrolytic oxidation in quantitative analysis.’’ 0. Gasparini(Abstr., 1907, ii, 650).“ Apparatus for the comparative observation of fluorescence.”H. Ley and H. Gorke (Abstr., 1907, ii, 920).“ A Filter-tube.” P. W. Shimer (Chem. Engineer, 1907, 6, 197).“ Laboratory apparatus f o r the evaporation of liquids by radiation‘‘ A gas-generating apparatus.” Eugen Miiller (.4 bstr., 1908, ii,m 7 , 23,187).F. R. L. Wilson (Proc., 1907, 22, 312).from above.”129).H. J. S. Sand ( J . SOC. Chem. Znd., 1907, 26, 1225)ANALYTICAL CHEMISTRY. 225As year by year the number of published papers dealing withanalytical subjects increases, the responsibility and difficulty attach-ing to the task of presenting this report become greater. It is clearthat exigencies of space render it impossible to refer to a very largenumber of communications, many of which record quite usefulobservations, and the author is compelled to select for notice thecomparatively few which, in his judgment, are of special importancein relation either to theory or laboratory practice.ALFRED CHASTON CHAPMAN.REP.-VOL. IV

ISSN:0365-6217    

DOI:10.1039/AR9070400199

出版商:RSC    

年代:1907

数据来源: RSC

摘要:

PHYSIOLOGICAL CHEMISTRY.IN the report which I wrote last year I began by regretting that itwas not my good fortune to be able to chronicle any great dis-covery. The same is also true this year. Last summer thephysiologists met a t Heidelberg for their triennial InternationalCongress, but there was nothing forthcoming of epoch-makingimportance. Indeed, most of the numerous papers read dealtwith matters which were already familiar, for with few exceptionsthe authors appeared to think it necessary to present a dc?iaufftof all that they had been doing within the preceding three years.This, however, was by no means uninteresting, for any matterseems more real when presented by word of mouth, especially whenit is illustrated by actual experiments. Many of the greatproblems at present on hand will need many years’ work yet beforeit is possible to draw general conclusions; and this is illustratedby the steady progress which Emil Fischer, Abderhalden, and theircolleagues are making in their attempts to unravel the mysteriesof the protein molecule.One characteristic of modern physiologicalresearch was strikingly brought out a t thk recent Congress, andthat is the ever-increasing part which chemistry is playing inaiding the solution of biological problems. Two of. the foursections into which the Congress divided itself dealt with questionsof bio-chemistry, and even then some of the chemical papers over-flowed into other sections. It is, however, not necessary t o labourthis point, for the Faraday lecture, which Professor Emil Fischerso recently delivered before the Chemical Society, has brought itout more forcibly and eloquently than anything I am able t o write.The year’s work has been far from barren; a glance through theabstracts in our Journal will show it has, in fact, been morevoluminous than ever.This is a matter for congratulation, foreach paper is a brick of varying dimensions in the great edificeof knowledge which is gradually being reared. But to an annualreviewer the plethora of work increases his difficulties in selectingsubjects for comment within the limits of space imposed upon himby the Editor. The proteins, as usual, must come first; then itwill be necessary to take up the subject of digestion, accuratPHYSIOLOGICAL CHEMISTRY. 227knowledge of which is progressing by leaps and bounds owing tothe new methods employed by E.S. London and his co-workerson the lines initiated by his great fellowrcountryman Pawloff.Then there are some important questions of general metabolismwhich have risen to the fore, including some relating to the gaseousinterchanges in the tissues, and the exchange of material in thefoetus. Enzymes, of course, are always with us, and among theserennet has been attracting considerable attention of late.1 Thegreat question of immunity has now a literature of its own, anda terminology of its own, which increases the difficulties of thosenot actually a u courant with the subject. This I do notpropose t o touch, except incidentally, in my present article.I propose, however, t o depart this year from my usual customand deal somewhat fully with a matter which has beenmonopolising the attention of the worker! in my own laboratory,and I do so not from any egotistical motives, but simply becauseit will furnish me with the necessary peg on which to hang relatedquestions which have been taken up elsewhere.The subject Irefer to is one of some intrinsic interest, namely, the chemistry ofnervous tissues; it is, of course, a long way from the phosphatidesand other constituents of the brain as studied in the test-tube t oan understanding of the phenomena of cerebral function ; never-theless, one can foresee a time when even the psychologist will notbe fully equipped for his labours without the assistance of hischemical brethren.On the pathological side I propose to dealwith one subject only, namely, that of diabetes, the papers onwhich have of late been unusually numerous. Whether theyhave made the subject any plainer is a matter for doubt; a t anyrate they have shown that some of our previous views are in partincorrect or need reconsideration, and thus the way is opened torenewed investigation on a surer basis.Proteins.Yrotamines and Histones.-Kossel has for some time pastregarded the protamines as the simplest members of the, proteinfamily, and obviously to understand the more complex substancesin the group it issfirst necessary to attack the constitution of thesimplest. One welcomes, therefore, Kossel’s most recent pro-nouncement on the subject. There are degrees of complexity* The principal points uiider discussion have lieen whether tlie clmige of caseinogcn into casein is physical or chemical ; inid wlietlicr or iiut pelsin and reiinet areidentical ; the view that they are tlie saiiie origiiially advanced by Pawloff isgaining ground ; a good suximary of the controversy is given by Gewin (Zeitsch.physiol.Chcm., 1907, 54, 32).Q 228 ANNUAL EEPORTS ON THE PROGRESS OF CHEMISTRY.among the protamines themselves, and $he simplest are thoseof the salmine group (salmine, clupeine, scombrine). Kosseland Pringle2 have shown that in these 8/9ths of the nitrogenpresent is in the form of arginine, and the remaining 1/9th asmonoamino-acids (alanine, serine, aminovaleric acid, and proline),two or more of which may be present.As arginine contains fouratoms of nitrogen, it follows that one molecule of monoamino-acidis present to every two molecules of arginine, and such protaminesare therefore diarginyl compounds. Reasons are given for believ-ing that the linking is symmetrical, thus: m b ' , aab", aab'l' wherea is arginyl and b', bN, b'll monoamino-groups. 'J%e protones whichare obtained on digestion as the first cleavage products of the prot-amines also contain 8/9ths of their nitrogen in the form ofarginine. Diarginylalanine will have a molecular weight 401,diarginylserine 41 7, diarginylproline 427, and diarginylamino-valeric acid 429. The molecular weight of the protones by theboiling-point and freezing-point methods of investigation wasfound t o be from 419 t o 423.It therefore appears that they aremixtures of the diarginyl compounds just enumerated. By theaction of nitrous acid on this mixture ornithine is split off, fromwhich it is argued that the symmetric arrangement is probablybaa rather than aab or aha.In histones, diamino-acids are again the most important cleavageproducts, arginine accounting for 25 per cent. of the nitrogen andlysine for 7 to 8 per cent. The first product of gastric digestion istermed histopeptone; this yields the same proportion of arginine,and it appears t o be a chemical unit, not a mixture as the protonesare. Moreover, histopeptone was obtained from several animaltissues and organs, most from the spleen and least from the liver.Attempts to obtain it from various vegetable proteins failed(T.Krasnosselsky 3).Spider's Silk.-The recent work of Emil Fischer4 on the silk-fibroin produced by the Madagascar spider shows that this sub-stance is also of a comparatively simple nature, and that it bidsfair to oust the protamines from their position at the bottom ofthe list. Like the fibroin from ordinary silk, it yields as itscleavage products mainly monoamino-acids, diamino-acids account-ing for only 5.2 per cent. Further, the various products differbut little in kind and quantity from those obtained from the silk-worm product. This investigation awakens many interestingreflections; it shows us in the first place how secreting organs ofsuch great morphological difference as the spinning pap of a spiderand the glands of a silkworm can form products so similarAbstr., 1907, i, 26ti.Ibid., 267. ' Ibid., ii, 566PHY S1 OLOGICSL CHEM ISTICY. 229chemically. The one is a carnivorous animal, the other lives oncomparatively cheap vegetable matter, and yet the adaptability ofthe laboratory of the living cell is so far-reaching as to lead tothe formation of an almost identical secretion in the two cases.It seems almost hopeless a t present to expect that even ProfessorFischer can go and do likewise, and yet so thorough is the know-ledge of the cleavage products obtained by accurate analysis thathe has stated he has selected silk-fibroin as the protein in particularin which to attempt a synthesis.Revers& Ze ProteiK-hyd.roZysis.-While we await the outcome ofthis great endeavour, it is interesting to note that from the otherside of the Atlantic comes the first successful attempt to synthesisea protein by means of ferment action.The amino-acids resultingfrom the hydrolysis of a protamine were placed by A. E. Taylor5in concentrated solution in contact with trypsin. The trypsinemployed was a very resistant one prepared from a mollusc. A tthe end of five months 1-6 grams of protamine were obtained,400 grams of protamine sulphate having been originally employedfor the hydrolysis. A blank experiment in which the trypsin hadbeen boiled gave negative results. The term synthesis throughferment action is, as the author points out, in the direct sense amisnomer; the ferment, of course, simply accelerates the reactionof synthesis, but as the result shows, even in the presence of theferment, the velocity is slow; still, if the result is sure, and thereis no necessity to doubt that, the experiment is in every sense anoteworthy one.A somewhat similar result with pepsin andparanuclein was obtained in the same laboratory by T. B.Robertson,G and more recently by E. Zak7 in connexion with theproteolytic ferment of Bacillus pyocyaneus.The Cleavage of Proteins and Polypeptides.--In the body proteinis successively acted on by gastric juice, pancreatic juice, anderepsin, and so it is broken down in stages t o its simplest cleavageproducts. m e importance of gastric digestion is far from clear,except in the case of a few proteins which are not readily attackedby pancreatic juice.It is well known that extirpation of thestomach, if the continuity of the alimentary canal is secured byappropriate surgical methods, is not a fatal operation either inanimals or men, and the view has found expression in somephysiological writings that the stomach is therefore a useless organ;the vermiform appendix, the source of many troubles, has beenplaced in the same category. This extreme view, a t any rate inrelation to the stomach, is not really justifiable. That an animalcan get on pretty well without a stomach is testimony t o the won-Abstr., 1907, i, 665. Ibid., 666, Ibid., 996230 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.derful power of compensation the body possesses, and is no proofof the uselessness of the organ wliich has been removed.I t waswith the view of clearing up the doubt as to the exact r81e gastlricdigestion plays that Abderhalden and Gigon undertook a researchin which edestin (the globulin of hemp seed) was subjected in t ~ i t r oto the successive action of the juices enumerated. So far as themain object of the experiments was concerned the results proveddisappointing, for there are unknown factors which complicate theproblem, for instance, the amount of erepsin in the intestinal juiceused for activating the pancreatic secretion. Nevertheless, a, pointof some interest canie out as a side issue; the edestin used con-tained 2.3 per cent.of tyrosine and 16.5 per cent. of glutamic acid.These substances were estimated in the digests, and the yield oftyrosine was 2.2 to 2.3 in all cases. The yield of glutamic acid wasnever so high as 16.5, but varied from 3 t o 11.5. This shows thatdigestive enzymes are able t o liberate certain amino-acids from theprotein complex more readily than others, and it should be addedthat tryptophan as well as tyrosine is wholly set free within a fewhours. Similar results were obtained when casein was used insteadof edestin (Abderhalden and Voegtling). The rate of proteincleavage varies very considerably under the influence of differentenzymes; it is well known, for instance, how greatly the velocityof the action is increased by trypsin in comparison with pepsin.The rate is still slower in the case of autolytic ferments.Evenafter fifty days’ digestion in the case of the liver, complexes givingthe biuret reaction were still present, and only a little more thanhalf the quantity of cleavage products were obtained which areformed by hydrolysis with hydrochloric acid (Abderhalden andPrym10). Curiously enough the presence of blood in an organlessens the rate of autolysis (Preti11). The inferiority of thestomach’s action was also demonstrated in the case o f the polypep-tides, diglycyl-glycine and triglycyl-glycine ethyl ester (the biuretlbase); whereas these substances are rapidly broken up andabsorbed in the intestine, any similar action of the gastric juicein dogs is minimal or absent (Abderhalden, London, andVoegtlin 12).The most interesting work on the cleavage of polypeptideswhich Abderhalden and his colleagues have produced is the dis-covery that the red corpuscles and platelets of the blood possessthe power of breaking them up, glycyl-Z-tyrosine being the dipep-tide mainly employed (Abderhzlden aiid Deetjen l3).The investi-gation of other cells is in progress, as also is the question whetherAbstr., 1907, ii, 893. !’ lhid., 893. I n Ibid., 89i.Ibid., 897. IbicZ., 892. Ibiil., 889PHYSIOLOGICAI~ CHEMISTRY. 231the higher polypeptides and proteins are decomposable in thesame way. White blood corpuscles have not yet been obtained insufficient quantity, free from other formed elements, in order totest the question on them, but lymph cells obtained from thethoracic duct and pus cells were found to have little o r no action.Turning to the fluid part of the blood, Abderhalden and Oppler1.Ifound that the plasma and serum do not produce that cleavage ofglycyl-Z-tyrosine which the coloured corpuscles and platelets bringabout so readily.A large number of other dipeptides were investi-gated with the same negative result, the only case where cleavageoccurred being that of 61-alanyl-glycine. Tri- and tetra-peptideswere, however, decomposed by the plasma, and this action cannotbe due to enzymes absorbed from the intestine, for both trypsinand erepsin are capable of splitting glycyl-Z-tyrosine easily. Truly,of the multiplication of ferments there seems no end.These inves-tigations were made on horses’ blood chiefly and they led Abder-halden and Rona 15 to perform similar work on human blood-serum.This fluid was obtained from thirty cases of disease; in eleventhere was a slight cleavage of glycl-Z-tyrosine; in the remainderthere was none. I n a few cases the urine was also investigated, butalways with negative results ; the number of observations, both onblood and urine, is admittedly too small a t present for definiteconclusions, nseful t o the pathologist and clinician, t o be drawn.Xrperim m t s on Dogs.-TIie difficulty of studying digestion andabsorption in the living animal is an obvious one, but the surgicalingenuity of Pawloff enabled him to make fistulous openings indifferent parts of the alimentary canal, and yet to keep his dogsalive for prolonged periods in an approximately normal state.Thismethod has been elaborated by London, and he has now in hispossession a number of dogs so operated upon that they are avail-able for experiments of the kind indicated. His numerous writingshave rendered even the names of his dogs familiar t o the readersof Hoppe-Seyler’s Zeitsclzrif t , in which he publishes his papers.Food can be administered, and the stage of digestion reached inany segment of the alimentary tube can thus be ascertained, aswell also as the amount of absorption which has occurred. I shallnot attempt even to summarise these numerous papers, but abetter plan will be t o take one or two definite examples of thesort of work which is possible under these new conditions, and Iwill start with a simple instance on the absorption of alcohol; itl4 Abstr., 1907, ii, 889.l5 Ibicl., 890232 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.was found that this substance is absorbed throughout the alimen-tary tract; in the mouth, naturally, the absorption is minimal;about 20 per cent. is absorbed from the stomach, 8.7 per cent. inthe duodenum, 53 per cent. in the jejunum, and 18 per cent. inthe ileum (Nemser 16).Another piece of work performed by Levites17 on the same dogsrelates t o the digestion of fats, especially with regard to the rela-tive absorption of the products of fat cleavage. If stearic, palmiticand oleic acids are given the quantities absorbed bear the rela-tionship 1 : 3 : 4 respectively.Under ordinary conditions ofdigestion most of the acids are saponified, and it was found thatthe absorbability of the sodium salts has the same relationship as,but is two and a half times greater than, that of the acids. Allthe glycerol is absorbed before the ileum is reached.18Still more interesting results were obtained on the absorptionof proteins and their cleavage products. If glycine d-alanine anddl-leucine are given by the mouth they are recognisable in thestomach for a long time; by far the greatest amount of theseamino-acids, probably all, leave the stomach by the pyloric orifice,and in the duodenum absorption begins rapidly. I n the lowersegments of the intestine they have entirely disappeared (Abder-halden, Prym, and London19).!lie relative unimportance of thestomach20 as an organ of absorption was shown in experiments inwhich meat was given; no absorption of nit,rogen occurred in thestomach, and this confirms previous researches in which white ofegg and bread were administered (London and Polowzowa21). Thecourse of digestion and absorption was followed by feeding theanimals on a definite protein (gliadin), and the issuing chyme fromdifferent regions was collected and analysed ; the rapid absorptionof amino-acids noted in previous work was confirmed, and aninteresting point was the identification of dipeptides, although itis doubtful whether these were precursors of the amino-acids orformed from them (Abderhalden, von Korijsy, and London 22).Morecomplicated problems are dealt with when mixed diets are given,and I will conclude my references to this branch of work bydealing with one of these. The course of events was followedThe results obtained donot correspond with those above stated, but the msthod used was to employ isolatedloops of intestine, which is a inore artificial condition.l6 Abstr., 1907, ii, 894.l 8 Compare v. Furth and Schutz (Abstv., 1907, ii, 976).l7 Ibid., 891.l9 Abstr., 1907, ii, 892.9o It is only fair to mention that Salaskin (Abstr., 1907, ii, 281) criticises London’smethods, which he regards as too complicated for the deduction of correct physio-logical conc!usione. He further believes that absorption of nitrogenous substancesoccurs in the stomach ; I cannot myself endorsp either of these views.~2 Ibid., 893.Abstr., 1907, ii, 894PHYSIOLOGICAL CHEMJSTRY. 233as before in one series when a pure protein (gliadin) was given,arid in another series when this was mixed with fat. The gliadiridisappears from the stromach into the intestine either with or with-out fat admixture four hours after the meal, whereas a t the sametime only 41 per cent. of the fat has passed on. But on examiningthe state of matters an hour earlier it was found there had beenmarked delay on the onward journey of thb protein if fat wasalso present. This “sorting out” action of the stomach, whichhas been denied by some observers, opens up the interestingquestion whether this may not after all be an important part whichthe stomach plays, and so some light is thrown upon what we havealready referred t o as the obscure subject of the real use of thisorgan.Further light has been shed on the question by an importantpiece of work carried out by Cannon23 in the Harvard Laboratory.He entitles his paper very appropriately, “The Acid Control ofthe Pylorus.” I n order that the processes occurring in the stomachmay advance in an orderly manner i t is necessary that the foodshould be retained in it until the acid which is secreted only inits cardiac half should be thoroughly mixed with the food, and there-fore until the portions of chyme in the pyloric portion are acid.The processes in the duodenum likewise require that the food shallbe checked by the pyloric sphincter until it is acid, otherwise itwill not stimulate the so-called duodenal reflex, which is in realitythe formation of the chemical stimulus (secretin of Bayliss andStarling) for the flow of bile and pancreatic juice.The stomachaccordingly is emptied by occasional discharges into the duodenum,the control being exercised by the condition of the pyloricsphincter. It is therefore necessary to explain the intermittentaction of this muscular ring, and it is found that acid in theantrum opens the pylorus, and acid in the duodenum closes it;because the acid in the duodenum is soon neutralised, the closureof the pylorus is intermittent. That acid in the antrum is thesignal for opening is indicated by the following evidence:-(1) Ifcarbohydrates are moistened with sodium bicarbonate, theirnormally rapid exit from the stomach is delayed; (2) if proteinsare moistened with acid, their normally slow exit is hastened;(3) the introduction of acid into the antrum through a fistulacauses pyloric opening; and (4) in an excised stomach kept alivein oxygenated Ringer’s solution, the pylorus is opened by acid onits gastric side.That acid in the duodenum keeps the pylorusclosed is shown by the following evidence:-(1) Acid introducedinto the duodenum inhibits gastric discharge, not by stopping peri-’L8 Abstr., 1907, ii, 974234 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.stlalsis but by closure of the pylorus; (2) if the pancreatic andbile ducts are t'ied and so neutralisatioii of the acid chyme byalkaline fluids prevented, the stomach cnipties more slowly thanunder normal conditions; and (3) the discharge of protein becomesrapid if the pylorus is sutured to the intestine below the duodenum,or if a ring is cut through the muscular coats immediately beyondthe pylorus.This last experiment shows that the effect from theduodenum is a local reflex action, mediated, like t'lie movementsof the small intestine, by the plexus of Auerbach.Metabolism.From a study of digestion and absorption it is an easy andlogical step to pass t o questions of the manner in which food-stuffsare utilised and finally disposed of through excretory channels.N~~tritive VuZue of Protein Cleavage Products.-Abderhaldenand Rona24 have published a research which confirms the workalready performed by Loewi and others, that the abiuretic cleavageproducts of protein are capable of maintaining nitrogenous equi-librium.A growing dog was fed on these materials with goodresults. I n this paper also they discnss the seat of proteinsynthesis, and arrive at the general conclusion that the main placewhere i t occurs is the intestinal wall. They base this conclusionprincipally' on the fact that they were unable to discover the amino-acids in the circulating blood during the course of absorption.They guard themselves by admitting the difficulty of detectingsmall quantities of subh substances in the blood, and the possi-bility that the tissue cells generally can build up their proteinfrom simple crystalline materials is not denied.This is tt. question which I entered into in last year'sReport (Vol.III., p. 234), and the conclusion there reached wasthat proteins are absorbed as amino-acids, and that evidence ofany special synthetic formation of proteins by the epithelium ofthe intestine is lacking; the greater part of them are never builtinto living protoplasm a t all, but they are rapidly converted by theliver into urea, and this finds an easy exit from the body by theurine. Abderhalden and Rona's paper revives the wholecontroversy once more, and it is therefore necessary to examinetheir conclusion a little more thoroughly. We may freely granttheir general trustworthiness as analytical chemists ; nevertheless,it is always a, dangerous practice t o draw conclusions from negativeresults; they, moreover, take no notice of the work of others whohave succeeded in obtaining positive evidence of the presence ofamino-acids in the blood during absorption.24 Abstr., 1907, ii, 892PHYSIOLOGICAL CT-TEMISTRY.235If we accept, their dictum that amino-acids are never found inthis situation, we are also bound to the view that all the cleavageproducts of protein cleavage are resyiithesised into protein, andthis is a conclusion which is directly contrary to the great mass ofexperimental evidence. The whole trend of modern work on meta-bolism shows that quite a small fraction of the products are ulti-mately utilised in this way, and that by far the greater part ofthem undergo exogenous metabolism and are discharged as areawithout having been built into protein molecules at all.Many years ago Kiihne argued that the amount of amino-acidsin the intestines is so small at any particular moment that com-plete protein cleavage cannot be considered t o occur to any greatextent. He lost sight of- the fact that the amino-acids were notformed for the purpose of accumulating there, but for absorption.So with amino-acids in the blood, they are not absorbed in orderto be stored in that fluid, but are removed from it by the tissuecells and dealt with there, either for the purpose of assimilationinto protoplasni or for discharge as waste material by the kidney.It is only necessary to suppose that this occurs very rapidly, andthis (together with the admitted difficulty of detecting smallamounts of amino-acids in the blood) will fully explain Abder-halden and Rona's negative findings.There is evidence thatmetabolic exchanges must occur with great rapidity. The blooddoes its work while it is in the capillaries when the velocity isslow and the vessel walls sufficiently thin for the transference ofmaterials in one or t h e other direction. It must, however, beremembered that the total length of capillary vessels through whichany given portion of blood has to pass does not exceed from 1/50to 1/30 inch (0.5 mm.), and, therefore, the time required for eachquantity of blood t o traverse its own appointed portion of thegeneral capillary system will scarcely amount to a second. It isduring this time that the blood does its duties in reference tooxygenation and nutrition, and the shortness of the time allowedshows the extraordinary rapidity of the exchanges which isnecessary.Abderhalden's reactionary conclusion on the matter shows alack of the acumen which is usually noticeable in his writings, par-ticularly as another of his pieces of research ought to have guardedhim from such an erroneous explanation of his results. I referto that on the behaviour of d-alanine in the organism of the dogwhich he undertook in co-operation with Gigon and L0ndon.~5 Heactually injected a large amount of this amino-acid into the bloodstream, and aftler the lapse of a short time attempted to find itL5 Absli'.: 1907, i, 891236 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.tJhere.Mixed wit,h blood in i i i f r o 3-43 o u t of 4 grams wererecovered by the ester method; but mixed with the blood in vivoonly a minute fraction was recoverable twenty minutes later. Nowif, after the injection of a massive quantity of amino-acid like8 grams into the circulating blood, horn 98 to 99 hundredths dis-appear in a few minutes, is it surprising that in the more gradualprocess of normal absorption it is difficult or without luck evenimpossible to separate out from the circulating fluid a measurablequantity of such substances ?Nutritive Value of Gelatin.-The exact value of gelatin as aprotein sparer” is an old problem which is ever cropping up,but upon which MurlinZ6 has recently done some exact work ondogs and on human beings; the sparing action of carbohydrateswas found to be an important factor in obtaining high replace-ments.The sparing action of gelatin is, however, not due to anydextrose to which it may give rise, but owing t o its containing sub-stances which are nitrogenous. Its principal amino-acid (glycine) canbe retained temporarily in the body, and this may serve to explainthe high replacement of other proteins by gelatin; but even withabundance of carbohydrate food it is not retained permanently.Metabolism of GZycine.-The question whether glycine can beformed in the organism de novo is answered in the affirmative byMagn~s-Levy.~~ Benzoic acid was given to cream-fed rabbits andto starving sheep; the output of glycine (as hippuric acid) wasfound t o be much greater than the amount which could have beencontained in the body proteins used up during the experiment.The possibility that the excess of hippuric acid in these experi-ments was formed by the oxidation of higher benzoylated amino-acids led to the subcutaneous administration of these acids torabbits and dogs, but in all cases the benzoyl derivatives passedunchanged into t’he urine ; in contradistinction t o these, formyl-glycine and formyl-leucine were broken down in the body.Prolonged Protein Feeding.-D.Forsyth 28 has shown that thebad effects which Chalrners Watson described as following theprolonged feeding of birds on excess of protein food were reallydue to lack of lime salts. I f lime salts are supplied in due amountthe ill results (on bones, thyroid, and other tissues) do not occur.Znanition.-Going to the other extreme, attention must nextbe drawn to the very complete investigation Cathcart has carriedout on a professional fasting man.The details are too lengthy to26 Abstr., 1907, ii, 793, 895. Compare also Rona and W. Miiller (Absfr., 1907,ii, 186), who find t h a t the addition of tryptophan and tyrosine do not increase thesparing action of gelatin.27 Abstr., 1907, ii, 977. 28 Ibid., 635PHYSIOLOGICAL CHEMISTRY. 237be repeated here, but they relate to botlh organic 29 and inorganic somaterials.Uric Acid.-Dealing next briefly with some of the moreimportant excretory substances, uric acid is usually one whichclaims its quota of papers.The past year forms an exception tothe rule, the only important work being that of Leathes.3l Theexcretion of this substance manifests a diurnal variation, beinggreater in the day than in the night. This is not a sign that thekidney is less active a t night, for the excretion of total nitrogenis as high as or even higher than during the day time. In feverthere is a rise in the excretion of most nitrogenous catabolites, butthe increased output is most marked in the case of uric acid andleast in the case of creatinine, which is a substance that Folinregards as a measure of tissue metabolism (as opposed to exogenousnitrogenous metabolism), and which, furthermore, remains constantin quantity in spite of variations in the food.The purine bases of the urine are also increased during fever,and the experimental administration of xanthine or caffeine t omonkeys will cause a rise in the body temperature.Sodium sali-cylate given simultaneously will prevent the rise in temperature. AsA. R. Mandel 32 states, it would be interesting to determine whetherxanthine forms a compound with salicylic acid analogous todiuretin ( = caffeine + salicylic acid) thereby rendering i t innocuous.It is not quite clear from Mandel’s work whether the increase ofxanthine and similar substances are to be regarded as the causeor the effect of a febrile condition; he appears to take the formerview.Creatine amd Creatinine.-If the popularity of uric acid as atheme for research is on the wane, that of the substances men-tioned at the head of this paragraph is in the ascendant.Thisis mainly due to the stimulus afforded by Folin’s views, and alsoto the ease by which they can now be estimated by Folin’s colori-metric method. It is not many years ago since it was believedthat the muscular creatine was ultimately discharged as urea, andthat the creatinine in the urine was mainly of exogenous originfrom the creatine of flesh foods. Owing to the introduction ofmore exact methods present teaching is almost exactly the reverseof this; there is no evidence that the creatine of the body is aprecursor of urea, in spite of the ease with which the transforma-Abstr., 1907, ii, 633.Ibid., 794. -See also similar experiments ondogs by Wolf (Abstr.,1907, ii, 634,794)) and “Metabolism in a Healthy Vegetarian,” by Little and Harris, ibid., 486.See also F.G. Benedict’s book on Imuition Zxperivkents on Han, recently issued bythe Cariiegie Institution.31 Abstr., 19Oi, ii, 114, 376, 32 lbzcl., 1908, ii, 54238 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.tion occurs in the test-tube. The injection of creatine into thecirculation leads to no increase of the urea excreted by the kidney.Whether creatine so administered raiseei the creatinine output inthe urine is also extremely doubtful. I f large doses of creatineare given much is excreted as such, the rise in urinary creatininebeing insignificant. Creatinine appears thus to be almost entirelyof endogenous origin, and, as already stated, Folin regards it asone of t’he principal measures of tissue metabolism.Its absoluteamount in the urine is remarkably constant, in spite of variationsin the diet, although differences are noticeable in different peopleand different animals. Muscular work also produces no alterationin the amount secreted unless the work is very excessive and per-formed upon an insufficient supply of fatty and carbohydrate food.The following is a list of the principal papers on the subject during1907. Grindley, Woods, and Emmett,33 using Folin’s method, havemade accurate estimations in meat and meat extracts of variouskinds. Among other points they have finally disposed of the state-ment made some years ago by G. s. Johnson that creatinine is themore abundant base of the two.Urano 34 also has performed similardeterminations; the mean amount of creatine in muscle is 0.4 percent., so that an averagesized man will have in the muscles of hisbody from 90 to 100 grams, a figure which brings home t o one thequantitative importance of this substance. Creatine is easily dialys-able, yet it does not dialyse out into the blood during life or intowater when the muscles are removed from the body. Given with thefood i t is largely retained in the body, and so Urano concludeswith Folin that the muscular protoplasm has the power of fixing it.K. 0. af Klercker35 confirms Folin’s views on the whole, butgoes a little further when he states that any biological relationshipbetween creatine and creatinine, which are so closely relatedchemically, is *questionable.He finds also that if the twobases are introduced into the blood stream both are excretedunchanged, and of the two creatinine is the more readilyeliminated. He regards the relationship of the urinary creatiniiieto muscular creatine as unproved, though here he probably goes toofar, for there is certainly some correspondence between the amountof muscle and the amount of creatinine; this is shown, for instance,by E. I. Spriggs’s36 investigation of a case of pseudo-hypertrophicmuscular dystrophy, in which a reduction in the muscular tissueswas accompanied by a sinking of the creatinine output, and alsoby Amberg and Morrill’s 37 observations on new-born children ; herethe constancy of the creatinine excretion is as marked as in adults,ilY Abstr., 1907, ii, 187 ; 1908, ii, 53.35 Ibid., 186.36 Ibid., 377. 87 Ibid., 799.34 Jbbid., 1907, ii, 111PHYSIOLOGICAL CHEMISTRY. 239but the total output is only about one-third of that in the adult,and this they connect with the smaller amount of muscular tissuein the child. Dorner 38 finds that inanition has no effect on theexcretion of creatinine, and makes the interesting discovery that inthis condition creatine itself passes into the urine. This againpoints to the breakdown of muscular tissue as a source of bothbases. He injected experimentally several bases, and with someobtained a rise in creatinine excretion, in other cases there wasnone, and he finally suggests the possible origin of creatinine fromauclein.Gottlieb and Stangassinger's 39 work on the subject deals mainlywith autolysis ; creatine is formed during the autolysis of muscleand other tissues; then it is in part transformed into creatinine byenzyme action, and finally both bases are destroyed; this action isattributed to enzymes, which they call creatase and creatinaserespectively.Similar changes are also asserted to occur in theurine. No doubt physiologists will await further evidence beforethey regard the existence of these ferments as proved.The only other paper I will refer to in this connexion is byDakin,4O and this deals with another aspect of the fermentquestion; he and Eossel were the discoverers a few years back ofarginase, the enzyme which splits arginine into urea and ornithine.Dakin now finds that this ferment is a specific one for the exclusivehydrolysis of d-arginine or of substances containing the d-argininegrouping.Creatine and other guanidine derivatives structurallysimilar to arginine are not hydrolysed by this enzyme.Other Buses in Meat Extracts.-Kutscher 4 l has been diligentlyexploring this neglected corner of the physiological field, and hasdiscovered a number of new bases, in addition t o others which, likecreatine, creatinine, choline, and neurine, were known previously.The new bases are labelled with quaint names, such as ignotine,42uovaine, carnitine, vitliatine, &c., a fact which in itself reveals howscanty is the present knowledge of their chemical composition.Thegood effects of beef-tea as a stimulant in disease are well known;its harmful action, however, is not yet so widely recognisd by themedical profession, and yet this is very marked in certain patho-logical conditions; no doubt some of the bases alluded to are thetoxic agents. A preliminary investigation with a view to deter-33 Abstr., 1907, ii, 709. Benedict and Myers (Abstr., 1007, ii, 492) mid Cathcait(Zoc. cit.), i n their work on inanition also found creatine in the urine.39 Abstr., 1907, ii, 637. Seeiiianii ($bid., 490) f0ur.d that the increase of creatininein muscular autolysis is specially great if a proteiii rich in arginmc, sach as gelatin,is added also.40 AbStr., 1907, i, 1099.QJ Probably ideatical with cariiosiue (Gulewitsch, Abslr., 1907, i, 264).t1 Ibid., 264 ; ii, 569, 708240 ANNUAL REPOR‘I‘S ON THE PROGRESS OF CHEMISTRY.mining this more accurately has been published by Slade,43, butthe deductions as t o which constituents the powerful action of meatextracts is due are put forward with reserve.I n moderate dosesthe heart’s rate and force are increased; this is not due to creatine,xanthine, o r urates; the increase in the movements of plain muscleall over the body is probably produced by ornithine and novaine;the agents concerned in causing diuresis, purgation, and othersymptoms are quite unknown.Lactic A cid.-This is the most important of the non-nitrogenouscatabolites in muscle, and the only one I shall touch upon. Hereagain we are on much-traversed ground, but Hopkins andFletcher’s44 treatment of the subject is by no means hackneyed,for they have been successful in discovering the reasons for somuch disagreement between past observers. Working with frog’smuscles they find that fresh resting muscle yields very smallamounts of the acid, but this amount is increased by injuries ofvarious kinds produced by mechanical means, heat, immersion inalcohol, and even by handling.The small amount of the acidfound in fresh muscle is probably due to unavoidable manipula-tion. It is easy to see how neglect of this point has led to dis-crepancies in previous statements. For the actual methods usedand the new facts elicited the original paper must be consulted;the somewhat lengthy abstract I presented when the paperappeared quite inadequately represents its importance ; perhapsthe most interesting of the discoveries recorded is that anatmosphere of pure oxygen prevents the survival development ofthe acid.Tissue Respiration.-The r61e that oxygen plays in vitalphenomena is a subject that I have treated in previous reports,and the obscurity surrounding this fundamental problem led theBritish Association some years ago t o appoint a committee to dealwith it.Previous to this time we were almost completely ignoranteven of the amounts of oxygen used by various structures in con-ditions of rest and activity, mainly on account of the difficultiesattendant on the estimation of blood gases. But the new andsimple methods introduced by Haldane and Barcroft render theestimation even in small quantities of blood perfectly easy to-day,and in various laboratories throughout the country data are beingaccumulated in relation t o this most important investigation.Asan example of the results obtained, we may take the work ofBarcroft and Dixon45 on the mammalian heart. The circulationof blood was maintained through the excised hearts of dogs andcats by perfusion from a living animal, clotting being preventedAbatr., 1907, ii, 379. 44 lbid., 373. 45 lbid., 366PHYSIOLOGICAL CHEMISTRY. 241by the administration of hirudin; the gases were determined inthe entering and issuing blood while the heart was in variousconditions, rate, amplitude, and tonus being taken into account.The amount of oxygen taken up by the heart varies directly withits activity; the output of carbon dioxide varies in the same waybut lags somewhat behind it.The output of carbon dioxide variesalso with the rate of flow through the coronary vessels, and theinteresting suggestion is thrown out that the vasomotor changesin these may be controlled by the metabolic products of whichcarbon dioxide is the chief. Be this as it may (and in view ofthe doubte expressed in some quarters as to whether the coronaryvessels possess effective vaso-motor nerves, it is we11 to withholdjudgment on the question), the figures obtained are full of interest;lhey show that cardiac, like voluntary muscle, is of lower metabolicvalue, weight for weight, than secreting organs such as the kidney,pancreas, and salivary glands.In the resting organs the pancreasuses 0.03 to 0.05 C.C. of oxygen per gram per minute, the sub-maxillary gland 0.03, and the kidney 0.03. The figures for thefeebly-acting heart are about onethird of these. When the organsare fully active the figures all rise, but the heart varies least,the highest figure obtained for the dog’s heart being 0.083 C.C.Vernon 46 has studied the subject on the kidney perfused withoxygenated saline solution ; the initial gaseous metabolism, whicha t first is as great as in the living animal, rapidly dwindles. In thecourse of the experiment the tissue proteins are dissolved out bythe perfusing liquid without affecting the tissue respiration, andfrom this observation the conclusion is drawn that tissue respira-tion is associated with non-nitrogenous side chains of Verworn’s‘‘ biogen ” molecules.This may be so, but Vernon’s experimentsdo not prove it, for the amount of protein washed away from thekidney cells whilst they remain alive can only be a small fractionof the total present.Metabolism in the Embryo.-Abderhalden and Hempe 47 esti-mated tyrosine, glycine, and glutamic acid in eggs in variousstages of incubation, but the changes found were so slight thatinferences as to the possibility of one amino-acid being changedinto others could not be drawn.Lochhead and Cramer48 found in rabbits that a t an early datein development the maternal placenta contains a large store ofglycogen; later on this decreases, and the decrease corresponds withan increase of the same substance in the foetal liver.Since theintroduction of Pfliiger’s exact methods of glycogen estimationseveral observers have expressed doubt regarding Claude Bernard’242 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.well-known statement on the richness of all foetal tissues inglycogen. The latest to do so are Mendel and Mitchell49; a highpercentage of glycogen is not characteristic of embryonic tissues ;the liver, however, does not in the pig assume its glycogenicfunctions early. They, moreover, regard glycogen simply as astore of nutrient energy rather than, as Creighton thought, apeculiar mark of histogenesis.I n their chemical studies on growth, the same observers haveinvestigated two other questions, namely, inverting ferments andpurine metabolism.They find that inverting ferments appearearly in the embryonic intestine, so contrasting with fermentswhich produce protein-hydrolysis. I n the embryo pig, maltase andlactase are present, but sucrase does not appear until after birth;lactase is, however, found in certain portions only of the intestine.I n birds, lactase is never found, but sucrase is present in the newly-hatched chick as well as in the adult hen.In reference t o purine metabolism they find that the nucleicacid of the embryo pig’s liver yields only two purine substances,namely, adenine and guanine. Nuclease and adenase are present,but guanase is absent as in the adult pig, although the otherviscera yield it at an early date.Oxydases and the uricolyticferment are not developed until after birth. A very similar inves-tigation with corresponding results has also been published byJones and Austrian.60 I n their previous work they have shownthat the distribution of the nuclein ferments (guanase, adenase,and xantho-oxydase) differs in different animals, and now theyhave found that it also differs in the same animal in differentphases of its development; thus in the liver of early pig embryosall these enzymes are absent; a little later adenase makes itsappearance and then xantho-oxydase, guanase being absent as i t isin the adult.CA emistry of A’eruous Tissues.I’h e Detection of Choline b y CJ~emicul Methods.--For some yearspast Mott and I have laid special stress on the importance of thediscovery of choline in the circulating fluids as a definite proof ofthe breakdown of nervous tissues, and our expectation that itsdetection would be useful in diagnosis has already been fulfilled.Allen and French in this country and Mansfeld in Germanypointed out that the chemical test with platinic chloride maylead t o confusion, since the chlorides of aniiiioii iuni and potassiumwhen treated with platinic chloride give rise t o crystals which areliable to be iiiistakeii f o r the plat,iiiicliloride of choline on mereinspection.A clieiiiical test is obviously best f o r clinical work iiiAbslr., 1907, ii, 896. 5u Ibid., 708PHYSIOLOGICAL CHEMISTRY. 243which, as a rule, only small quantities of cerebro-spinal fluid orblood are available; a clinical observer also has usually neither thetime nor the opportunity of applying any further tests to crystalshe is observing. It was therefore necessary to seek for othertests for choline which are not given by the inorganic chlorides.As a result of 0.Rosenheim’s search in this direction, he suc-ceeded in discovering three.51 One of these is a colour reaction withalloxan; the second is the formation of a characteristic red pre-cipitate with potassium bismuthoiodide, and the third, is amodification of the iodine reaction. This third test, being the mostcharacteristic and readily applicable to clinical uses, is the only oneI shall describe in full here. The yellow crystals of choline platini-chloride are prepared from the alcoholic extract in the usual way,and to these a strong solution of iodine in potassium iodide isadded.The crystals alter in a characteristic way, and the changecan be watched with the microscope. In the course of a fewminutes the yellow octahedral or prismatic crystals disappear andtheir place is taken by dark brown plates and prisms in large quan-tities which show marked dichroism, are doubly refracting, and havea superficial resemblance to the well-known hzmin crystals. Theyare composed of choline periodide (C,H,,ONI,), but are extremelyunstable, and if the slide is allowed to stand so that the liquidgradually evaporates the crystals begin to disappear and their placeis taken by brown, oily droplets; this indicates the formation of alower iodide.I f now a fresh drop of the iodine solution is addedthe crystals gradually form once more, and their formation anddisappearance can be watched repeatedly. I f ammonium orpotassium platinichlorides are present on the same slide theyremain unchanged under the action of the iodine solution.Donath 52 has also described another distinctive character of thecrystals of choline platinichloride ; namely, they are doublyrefracting, whereas the platinichlorides of ammonium o r potassiumare not. Rosenheim has confirmed this statement, and in somecases has made out another fact which is not devoid of significance.If he obtains from a case of pathological cerebro-spinal fluid a slideof the mixed platinichlorides and places i t in the field of thepolarising microscope the inorganic platinichlorides exhibit nodouble refraction, but a large proportion of the crystals presentshow the phenomenon.If he then subjects the slide to his iodinetest many of the doubly refracting crystals are transformed into thebrown crystals of choline periodide, and others yield crystals ofdifferent, forin from these and therefore consist of other platini-chlorides, probably of organic nature, although they have not yet.jl Abstr., 1‘306, ii, 133244 ANNUAL REPORTS ON THE PROGRESS OF CHEiIfISTKT.been identified. This is only what one would expect; the chemicalstructure of nervous material is so complex that the cleavageproducts liberated during the degenerative process must benumerous.The importance of the detection of choline arisesbecause it is at present the only one of these numerous substanceswhich can be identified with certainty and which can be detictedwith comparative ease. Its presence indicates the breakdown ofone of the most abundant and best known of the constituents ofnervous matter (lecithin), but suggests that it must be accom-panied by the presence of numerous other similar and even dis-similar compounds.In Rosenheim’s53 most recent paper on the subject he gives theresults of his examination of numerous specimens of blood andcerebro-spinal fluid from cases of nervous disease, and also pointsout that the procedure of testing may be shortened by applyingthe iodine reaction direct to the alcoholic extract of the sus-pected fluid without the necessity of preparing crystals of theplatinichloride first.I had, happily, keptl a considerable number of tlie preparationsof crystals which Mott and I made years ago, and from which wedrew our previous conclusions.On examining these afresh by thenew means of identification we now possess I found that they donot consist wholly of the choline compound, but contain a consider-able admixture of inorganic platinichlorides, especially thepotassium salt. We, however, still hold that the obtaining of alarge crop of crystals, whether they be those of the choline saltor of a mixture of the potassium and choline salts, is diagnostic ofextensive breakdown in nervous tissues. The contrast betweensuch cases and the insignificant yield from normal fluids is moststriking.This is intelligible when we take into account the highpercentage of potassium that, according t o the work of Macallumand of Macdonald, nervous tissues contain. Some preliminaryexperiments indicate a considerable increase of the potassium inthose cases of disease where disintegration of nervous tissues hasoccurred and where choline is also discoverable.The Physiological Test for ChoZine.-Although the chemical testfor choline is the one most suitable for clinical work, thephysiological effect which choline exercises on blood-pressure is notdevoid of interest. Swale Vincent in his earlier work on thephysiological action of extracts of nervous tissues found that theintravascular injection of such extracts caused in anzesthetisedanimals a considerable fall of arterial pressure.I published simul-taneously the same result, and attributed the fall t o the presenceG3 Abs.fr., 1907, ii, 637PHYSIOLOGICAL CHEMISTRY. 245of choline. Vincent, however, denied that choline was present,Subsequently, with Cramer, he amended this statement, and thensaid that the choline present was in the form of dicholineanhydride. The existence of this compound is very problematical,and the analytical evidence presented is not very convincing; still,the suggestion that compounds or modifications of choline mayexist in the body is not entirely unwarranted. Vincent andCramer also found what I had missed, namely, that there are othersubstances present in such extracts which are readily soluble inether and which produce a much more powerful depressor effect onthe blood-pressure than choline, and that in the case of such sub-stances the effect is not abolished by the administration of atropine(as that of choline is).They did not attempt to identify thesematerials; i t is quite possible that they are absolutely distinct fromcholine; the view is also permissible that they are derivatives ofcholine. This second view gains point from a study of some experi-ments which Reid Hunt and Taveau brought forward a t themeeting of the British Medical Association in Toronto last year.64They have prepared and studied the physiological action of asmany as nineteen compounds of choline, and they suggest the possi-bility that some of these may be formed in the body. Some ofthem are more and others less active than choline itself; the mostpowerful is acetylcholine; this is one hundred times more activein producing a fall of blood-pressure than adrenaline is in pro-ducing a rise; the injection of a few C.C.of a solution containingit, diluted with one hundred million times its volume of water,produces a distinct effect in a rabbit. The action of acetylcholineis not annulled by atropine, and it is capable of overcoming theeffect of adrenaline. On the other hand some of the choline deriv-atives examined are less powerful than choline; the introduction ofa phenyl group, for instance, diminishes its depressor effect.As an outcome of his work Reid Hunt recommends two new testafor choline; one is the formation of the acetyl compound to renderthe physiological test more sensitive; the other is the formationof the benzoyl compound; this gives it distinctive crystallineplatinum salt which cannot be confused with the platinichloridesof ammonium or potassium.I think that in the future thoseengaged in research will have therefore no lack of methods torender the detection of choline a matter of no IdifKculty.Several observers have surmised that the breakdown of lecithinin the body is due to the activity of a ferment, although hithertoattempts to isolate the enzyme have failed. Rosenheim in hislatest paper just quoted has in his examination of certain non-54 Brit. Mecl.J., 1906, 11, 1788246 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.nervous tissues for choline found i t as a result of autolysis,although i t is not present as such when the tissue is fresh.Marinesco 55 suggests that in peripheral iierves the ferment isformed by the neurilemmal cells which actively multiply duringWallerian degeneration, but this interesting hypothesis has not yetreceived any experimental confirmation.The CJfioZesteroZ of the Brain.-Cholesterol is an abundant con-stituent of nervous tissue, anid this cannot be devoid of physiologicalimportance, but at present we know nothing either of its mode oforigin, its destination, o r its function. It is usually isolated fromthe brain by extraction with ether, and subsequent precipitationof this ethereal extract with alcohol.But ether extraction of freshbrain is a troublesome operation; i t swells up, and filtration andcomplete removal of the cholesterol is difficult and tedious.Baumstark 56 avoided some of these drawbacks by subjecting thebrain to ((ether dialysis,” but the time required for this is fromone to three months, anid even then the extraction of cholesterolis incomplete. A second disadvantage is that ether dissolves notonly cholesterol but large quantities of other substances as well,and the separation of cholesterol from these involves severaloperations and is incomplete. Baumstark only obtained 35 percent, of the total cholesterol by this method; the rest is carrieddown with the precipitates of lecithin, &c., and can only be freedfrom them by saponification, a fact which led him to assume thepresence of cholesterol-esters in the brain.Zuelzer 57 precipitatedthe phosphatides from their ethereal solution by acetone, andeffected in this way a more complete separation.It occurred, however, to Rosenheim58 to use acetone as theextracting agent. This dissolves only cholesterol, and its usetherefore enables one to obtain hhat substance readily and alsofacilitates the study and separation of certain other constituentsof nervous material. It is, however, necessary to remove waterfirst, and this is done quite simply by means of plaster of paris.The brain material is passed through a mincing machine aad thenmixed with sand and about three times its weight of plaster ofParis.I n a few hours the mass sets hard, and this is easilybroken up into a powder which lends itself readily to extractiontyith acetone at the ordinary temperature. The first extractusually contains some water and therefore less cholesterol ; butfrom the second and third extracts the bulk of the cholesterolcrystallises out in an almost pure condition on evaporation of thesolvent.55 La Pressc Mcclicnle, 16 Fch., 1907.57 Ibid., 1899, ii, 504.N Abstr., 1885, 918.5y Ibid., 1906, ii, 240PHYSIOLOGICAL CHEMTSTRY. 247Using this method, Miss 34. C. Tebb59 found that the extractionof cholesterol was complete, and 110 further yield occurred onsaponification. Baumstark’s idea that some of the cholesterol isfree and most of it in combination is therefore incorrect. WhileMiss Tebb’s work was in progress the same conclusion thatcholesterol occurs in a wholly free condition in brain was reachedby a different method by Biinz.60 This observer paid specialattention to melting-point determinations ; the melting point islowered when cholesterol and cholesterol ethers are mixed together.Miss Tebb did not, however, find the extremely great depressionswhich Bunz described.This, after all, is a small point of difference.The main conclusion is that by the use of trustworthy methods ithas now been shown that cholesterol occurs as such in nervoustissues, and not in the form of cholesterol ethers or cholesterolesters.Protagon.-This term was originally used by Liebreich in 1865for a crystalline substance which can be obtained from brain by asimple process of extraction either with ether alone o r with alcoholafter preliminary treatment with ether.The same substancehad, however, been obtained by practically the same method asearly as 1834 by Couerbe, and by him designated ce’r6brote. Perhapsno substance of physiological importance has undergone so manyvicissitudes as protagon ; the pendulum of scientific opinion hashere swung backwards and forwards, protagon being alter-nately regarded as a, chemical individual and as a mixture ofsubstances. The matter, however, is a t last definitely settled onceand for all. Protagon is a mixture, as Thudichum in 1874 was thefirst to prove, and the use of the term has now only a historicaljustification.A series of death-blows to protagon as a chemicalunit has been struck in America by Gies and his colleagues,61 andin England by 0. Rosenheim and Miss Tebb.62 A series of blowshas been necessary, for protagon has died very hard and the mostrecent attempt to resuscitate it has been made by Cramer,63working in Liebreich’s laboratory and later a t Edinburgh in con-junction with Lochhead,6* but the obvious fallacies of this workhave been amply demonstrated by both the American and theEnglish workers referred to.Cramer has introduced a new method of preparing protagonwhich is very largely a reversion to Couerbe’s original process,and he concludes “ t h a t the close agreement between thephosphorus percentage of various samples of protagon prepared by59 Abstr., 1906, ii, 241.61 Lesein and Gies, ibid., 1903, ii, 90 ; W.Koch, ibitl., 1902, ii, 676 ; Posnerand Gies, ibid., 1905, i, 54 ; Gies, ibid., 1907, ii, 995.63 lbid., 1904, i, 462.Ibid., 1905, ii, 841.Abstr., 1907, ii, 995. 6J Ibitl., 1907, i, 673248 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.diverse methods is strong evidence in favour of the view thatprotagon is an individual substance of a well-defined chemicalcomposition.” The term close agreement involves percentagesvarying from 0.97 to 1.5. But even if the agreement were stillcloser one might nevertheless be dealing with a number of sub-stances mixed together in approximately the same proportion.Cramer has evidently not grasped the fact that the question a tthe root of the matter is not: Can products closely resemblingthe protagon of Liebreich and of Gamgee and Blankenhorn be pre-pared by new methods? But rather, is the product prepared byany of these methods a sample of a definite chemical individual?Rosenheim and Miss Tebb, for instance, have prepared a sub-stance with the properties of protagon by another new method,and yet their conclusion is the exact opposite t o Cramer’s.Thisnew method briefly consists in removing water by plaster of Parisand then cholesterol by cold acetone as already described. Hotacetone then extracts protagon, and this is deposited in crystallineform when the hot solution cools. No doubt the fact that protagonshows a microcrystalline structure has influenced chemists inaccepting it as a uniform chemical subsbnce,65 but the data onthe other side are now too strong to allow this fact to overbalancethem.The workers in America and those in my own laboratory haveapproached the problem in somewhat different ways, but their con-clusions are the same.As I am naturally more familiar with thework at King’s College, and have seen the greater part of theexperiments while in progress, I will be content with mentioningthe grounds upon which Dr. Rosenheim and Miss Tebb base theirconclusions; these are briefly as follow :-1. Liebreich’s, Gamgee and Blankenhorn’s, and Cramer’sprotagon represent practically the same substance as Couerbe’sc6rBbrote of 1834.2. A similar substance can be obtained by the acetone methodreferred to.3.All of these protagons resemble one another in microscopicappearance, and roughly in phosphorus percentage.4. But all and each of them may be split into substances ofwidely varying phosphorus and nitrogen percentage by methodswhich involve no chemical breakdown, namely, by simple fractionalcrystallisation a t different temperatures or with different solvents.6 . These products aIso show great differences in optical activityand in the amount of galactose split off by acid hydrolysis.6. Protagon (with about 1 per cent. of phosphorus) is thereforeO5 It has certainly influenced myself in previous writings on the snlnjectPHYSIOLOGICAL CHEMISTRY. 249not a definite chemical compound. It consists of a mixture ofsubstances; some of these (such as phrenosin) are free fromphosphorus and others (such as Thudichum’s sphingomyelin) arerich in phosphorus.7.The base called sphingosine by Thudichum, as well as choline,is found amongst the products of protagon-hydrolysis.Cramer and Lochhead state that ‘(the view that protagon is amixture of substances . . . cannot be accepted until the substancesconstituting the mixture have been isolated.”With this statement all will be in agreement. It, however,implies that the substances have not been isolated, and so con-veniently disposes of a great deal of work of those who fromThudichum onwards have attempted to obt’ain these substances ina pure condition. One such substance has certainly been isolated,namely, pbrenosin under different names by various workers,including one who believed in the individuality of protagon(namely Gamgee, who called it pseudo-cerebrin).That we are lessfully acquainted with the other substances is due to the circum-stance that the investigation of the chemistry of the brain issurrounded by difficulties which can only be appreciated by thosewho have actually worked a t the subject.But since Dr. Rosenheim and Miss Tebb completed the paper Ihave given the substance of, they have continued t o work at theseparation of protagon into its main constituents and are atpresent engaged in examining and analysing them. The methodemployed is that of systematic fractionation by means of alcohol,chloroform, and acetone.The largest fraction (approximately60-70 per cent. of the original protagon) comprises at least twocrystalline substances which are nearly phosphorus free (P = 0.09).The quantity of phosphorus in the remaining substances (of whichso far one has been obtained in crystalline form) amounts to about3 per cent. It is evident that a mechanical mixture of these twosubstances in the above proportions would enable one artificially toreconstitute ‘( pure protagon ” with a phosphorus percentage offrom 0.9 to 1.2.Paranucleo-protagon.-This is the name given by Ulpiani andLelli 66 t o a compound in the brain in which they believe the protagonis combined ; they state it can be resolved by alcohol into protagonand paranuclein. A t the time this work was performed the ideathat protagon is a chemical unit was held by most workers.Para-nucleo-protagon is extracted from the brain by means of chloro-form. Gies and Steel67 have now shown that it, like protagon, isa mixture containing other substances besides the two mentionedThe details will, however, be published later.OCi A b s t ~ . , 1902, ii, 573. 67 Ibid., 1907, i, 1097250 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.by Ulpiani and Lelli; probably, however, none of the constituentsof protagon is really combined with a iiuclcin-like substance.Sulphur in t h e ~TO.L'OICS Systerib.-The S U I ~ ~ ~ L W conipouiids iuiiervous material have always attracted W. Koch in his work onbrain chemistry, and his latest communication on the subject hasonly just been pubIished.68 He divides the sulphur-containingmaterials into four groups : -Although he does not believe inthe entity of protagon, he suggests that its lecithin and cerebriiiconstituents are linked together by an organic sulphur radicle.These consistas to one-tenth of inorganic sulphates and the remainder of ataurinelike substance.(3) Extractives soluble in water after previous extraction withalcohol and ether.These are principally inorganic salts, possiblymixed with a gelatin-like protein.(4) Proteins, mainly globulin, neurokeratin, and nuclei-protein.Grey matter contains chiefly globulin, nucleo-protein, and neutralsulphur compounds. White matter contains a larger proportion ofneurokeratin and lipoid sulphur.Koch's work strikes one as being problematical and unfinished.His suggestion that the constituents of protagon are chemicallylinked together is supported by the flimsiest analytical evidence, andwill do harm if it serves to bolster up the protagon heresy.Hisstatement that lecithin is one of the constituents of protagon iswholly incorrect, and has been abandoned for many years fromGamgee onwards. A very similar criticism may be passed upon hissuggestions regarding the physiological r5le played by the sulphurcompounds. No one doubts the necessity for brain-function of anexcess of free oxygen; but whether it is the sulphur-containinggroups which are specially susceptible of oxidation is amatter on which we have no certain knowledge. It isimportant, of course, to have ideas of this kind even if theyare ultimately found to be nothing more than crude guesses,for they furnish a stimulus to investigate the matter moredeeply.The very remarkable disease called Bementin pracox isattracting considerable attention from alienists a t the present day.Three cases of this malady came post-mortem into Koch's hands,and on the supposition that some of the symptoms could beexplained by deficient oxidation in the brain he investigated thesulphur compounds; the lipoid sulphur was present in normalamount; the neutral sulphur was reduced by 35 per cent., and theinorganic sulphur was increased. It will probably be better a t(1) Lipoids, such as protagon.(2) Extractives soluble in 95 per cent. alcohol.fiQ Ahstr., 1908, ii.52PHTSIOLOGICA L CHEMISTRY. 251present to be content with pigeon-holing these scanty data andleave coiiclusioiis for a later year, when our knowledge is riper.Lccithiic (rnd Pli osylmtides in other ‘Sz;twations.-Althoughlecithin and other phosphatides have attracted special attention inthe nervous system because of their abundance in that situation, itjmust be remembered that they are universally present in all livingprotoplasm. Thus the phosphatides of egg yolk are according totheir solubilities separated by Stern and Thierfelder 69 into threegroups, and a preliminary study of their properties is in progress.A similar unfinished piece of work on the lecithin-like substancesobtained from cardiac and voluntary muscle has been publishedby Erlandsen,70 who finds that they differ in the kind of fatty acidthey contain and in other particulars; he classifies them into mono-aminomonophosphatides, diaminomonophosphatides, nionoamino-diphosphatides, and diaminodiphosphatides.The lecithin of bone marrow has been studied by Otolski71 andby Gliken.72 The paper by the former deals mainly with methodsof separation ; the lecithin found yields on decomposition choline,glycero-phosphoric acid, and unsaturated fatty acids.The paperby the latter is quantitative; the amount of lecithin is deducedfrom the phosphorus content of the ethereal extract. The amountof lecithin in the fat averages 2 t o 4 per cent.; in horses it is lower(1.4 per cent.); the highest numbers were obtained in very youngpigs (28 to 47 per cent.); speaking generally its amount diminisheswith age.T?Le Possib Ze Ftcnctions of Lecithin and C?toZesterot.-Theuniversal distribution of these two substances in all living proto-plasm is a fact that has long been known.Lecithin has been recog-nised as an important constituent of food, and its administrationin cases of malnutrition is stated to have been attended with goodresults. Its stimulating action on individual organs such as theexcised heart has also been noticed.73 The exact way in which itacts is still hypothetical, but a ray of light has entered from avery unexpected quarter, namely, a study of the action of snakevenom. Preston Kyes was the first to discover that in the processof hEmolysis, which is one of the results of the action of snakepoison, lecithin acts as the amboceptor anchoring the poison on tothe cell i t attacks.Adopting Ehrlich’s hypothesis that theaction of toxins is analogous to that by which the food-proteinsare assimilated by living cells, one can deduce from this observ-ation the possibility that lecithin may assist the assimilation ofAbskr., 1907, ii, 896. 7O lbid., i, 371.73 See Danilewsky, ibid,, 981.7l lhid., 666.TZ Ibid., ii, 566252 ANKUAL REPORTS ON THE PROGRESS OF CHEMISTRY.food materials beneficial to the organism as well as of those which,like snake venom, the organism would prefer to be untroubled with.It is three or four years ago since Kyes made his original state-ments on the subject, but his views havebeen fully confirmed, andfurther details of the action of toxolecithids worked out.74Hsemolysis, of course, is only one effect of certain poisons; it isprobably, however, only a sample of what occurs in other cellsand is far more readily studied than the changes in other cells are.It may be produced by purely physical agencies, as when water isadded to red blood corpuscles; but what may be called ferment-ative hEmolysis is more interesting, because it is a process, asalready stated, which runs on the same lines as the assimilation offood material.Neuberg and Reicher 75 regard both hzmolysis andagglutination as intermediate stages in lipolysis, and theimportance of lecithin as an amboceptor accentuates this hypothesis.Noguchi76 confirms this view, and further shows that neutral fats(such as triolein) may play the same part a t any rate in someforms of hzmolysis and bacteriolysis.One naturally speaks with caution in dealing with a new andstriking hypothesis which has still t o stand the test of time andfurther experiment; but as far as one can judge a t the presentstage it does seem to be definitely proved that lecithin, and possiblyother fatty compounds, are important auxiliaries and possiblynecessities in the ferment-like actions produced by toxins ; weshall also be fairly safe in accepting Ehrlich’s views on the analogybetween the mechanism involved in the assimilation of toxicproteins and those which are non-toxic, and so the importance oflecithin during normal assimilation may be provisionally accepted.This has led us a long way from our starting point, the lecithinsof the brain; it is quite possible that the large amount of thesesubstances in nervous tissues may have some additional significanceof its own there, or it may be that such actions as lecithin possessesin protoplasm generally may be specially called into play in thechemical exchanges which lie a t the root of nervous activity.Not only have the researches referred to been useful in clearingup some points in relation to the function of lecithin, but theyhave also thrown light on what is a still more obscure problem,the function of cholesterol.Here again, however, the enormousquantity of cholesterol in nervous tissuer, is strikingly diff erentfrom what obtains in other organs of the body.Moreover, its wer4 See, during the present year, Morgenroth and Carpi on “ Bee Poison,” Abstr.,1907, ii, 286 ; on “Cobra Venom,” ibid., 570 ; Iiyes, ibid., 569 ; Teruuchi, ibid.,571.75 Abstr., 1907, ii, 570.’is Ibid,, 890, 974. See also Liebermann, ibid., 973PHYSIOLOGICAL CHEMISTRY. 253have already seen, the cholesterol of the brain is free; that ofother tissues is probably in combination as esters; this, a t any rate,is the case for the cholesterol of the blood.Researches on the lines of immunity, such as have demonstratedthe favouring action of lecithin, have shown that cholesterol hasthe opposite action, and it may therefore, be that the normalfunction of this interesting member of the terpene group is aprotective one, enabling the body cells to withstand the action oftoxic agents. In support of this view we may quote the follow-ing : -H.Pribram77 showed that after feeding on cholesterol the per-centage of that substance rises in the blood, and resistance t ohzemolytic agents is increased. Morgenroth and Carpi 78 foundthat the hzmolytic action of a mixture of bee poison and lecithinis decreased by cholesterol. P a s c u ~ c i , ~ ~ in experiments with artificialblood corpuscles, demonstrated the protective influence of a coveringmembrane which contained cholesterol. Hausmann go obtainedcorresponding results when investigating the hzemolytic action ofsaponin. Hausmann went further than this and showed that inorder that cholesterol may exercise this action the hydroxyl groupand the double linking must be intact, and this has been confirmedby Abderhalden and Le Count.81Glycogen, S U ~ I ’ , Diabetes.As one of the main practical interests of a study of carbohydratemetabolism is the condition in which that metabolism is upset, Imake no apology for grafting my summary of the year’s work onglycogen and related subjects on to a general account ofdiabetes.The term diabetes doubtless includes many pathological condi-tions which all possess in common the symptom of glycosuriaand usually of glyczmia also.I n animals, the condition can beproduced by diverse experimental means, of which it will besufficient to mention the following : -1. Diabetic puncture.2.Extirpation of the pancreas.3. Administration of phloridzin.4. Administration of adrenaline.1. Diabetic Puncture.-Claude Bernard made the discovery thatinjury t o the grey matter in the floor of the fourth ventricle inthe region of the vaso-motor centre leads t o glycosuria. Thisform of glycosuria is of interest t o the medical man, because brain77 Abstr., 190f, ii, 105.bo Ibid., 744.78 I b i d . , 286. ]bid., 1905, ii, 729.81 Zcitscli. Zxp. Path. Ther., 1905, 2, 199254 ANNUAL REPORTS ON THE PHOGBESS OF CHEMISTRY.disease in man, especially in the region of the bulb, is frequentlyassociated with sugar in the urine. It cannot be regarded as ofpurely vaso-motor origin, since a dilatation of the abdominalvessels produced by other means is not accompanied by a diabeticcondition. There are experiments recorded which show that theliver nerves have a direct influence on the liver cells quite apartfrom their influence on the blood-vessels ; for instance, stiniulationof the vagus and also of the coeliac plexus is stated t o lead todiminution of the hepatic’ glycogen and a corresponding increaseof sugar in the blood.It may be that puncture diabetes is due t oinjury t o or stimulation of a centre controlling the action of thissecretory nervous mechanism. J. J. R. Macleod 82 has recentlyinvestigated the glycogenolytic fibres, as he terms them, and findsthem present only in the splanchnic nerves and not in the vagusif all precautions against the occurrence of asphyxia are taken.The discovery of the I‘ diabetic centre ” gave rise to the erroneousidea that all cases of diabetes are of nervous origin; but injuryto the centre is only effective in its results when the liver containsglycogen; puncture diabetes cannot be produced in an animal inwhich the store of glycogen has been depleted by fasting.The transformation of glycogen into sugar is accomplished by aferment (liver-diastase), and a series of interesting papers byBang83 have dealt with the amount of this ferment present undervarious conditions, the experiments having mainly been performedupon rabbits, Among other points, the influence of the nervoussystem on glycogen metabolism wits investigated.The effect of a blowon the neck is to cause an increase in the liver-diastase, the liverenzyme being independent of the blood-diastase. Bernard’spuncture diabetes is similarly produced ; the primary stimulationis, however, followed by inhibition, and it is suggested that inphysiological conditions, sugar production is a balanced actionbetween stimulation and inhibition, and possibly the centres con-trolling the two actions are distinct.The efferent path for thenerves controlling this action in the liver is the sympathetic (thisconfirms Macleod’s view just stated). It was, however, found thatstimulation of the central end of the cut vagus produced glycaemiaand glycosuria whether the liver contained much or little glycogen.This reflex diabetes, as it may be termed, is thus independent ofthe liver, and is believed to originate from the change of glycogeninto sugar in the muscles of the body.The independence of theglycogenic function of the muscles, apart from that of the liver,is an old idea which has within the past year received supportfrom cle Filippi’s s4 experiments on dogs with an Eck’s fistula.sL At)&., 1907, ii, 800. bd JDul., 487, 634, 900. k4 lDiJ., 707, 794PHYSIOLOGICAL CHEMISTRY. 255When the liver is thrown out of gear by this operation the animalis still able t o utilise starch, and shows no sign of glycosuria on amoderate diet; still, it is found that quite small doses of somesugars (e.g., lactose) will lead to their appearance in the urine,and the organism is absolutely intolerant t o lzevulose. The amountof hepatic glycogen is greatly reduced by the operation, but theamount in the muscles remains unaltered.This not only showsthe independence (or it may be partial independence) of the twotissues in carbohydrate metabolism, but also explains how the lattercan go on in spite of the diminution of hepatic activity.I n these various forms of nervous diabetes there is no funda-mental disturbance of the power of the organism to burn andutilise sugar; there is simply a diminution or overstraining ofthe sugar-holding capacity of certain organs, and therefore theycannot be classed with diabetes mellitus in the strict sense. Thesame is true for what is called “alimentary glycosuria,” whichoccurs when sugar is given in larger amount than the liver candeal with, and which is most readily produced when the metabolicfunctions of the liver are “ below par.” This, at any rate, is theusual view taken of alimentary glycosuria ; de Filippi alone amongrecent writers feels doubtful whether it is a symptom of liverinsufficiency, on the grounds that he has been unable to find patho-logical changes in that organ in cases of the kind.It is, however,quite possible that the hepatic functions may be depressed withoutany anatomical changes being detectable either with the nakedeye or the microscope.2. Extirpation of t h e Pcizzci.eas.-Minkowski was the first to showthat removal of the pancreas in animals leads to a glycosuriccondition, and this has been recognised as a true diabetes in whichthere is an impairment of the capacity of the cells of the body toprepare the sugar for oxidation.Many cases of diabetes in manare undoubtedly produced by disease of the pancreas. It is a longway from man to the low group of fishes called selachians (dog-fish, &.), but even here extirpat,ion of the pancreas causes sugarto appear in the blood; 85 there are obvious difficulties in examin-ing the urine of such animals.It has been generally assumed that pancreatdc diabetes is notnervous in origin, since injury to the nerves in the region ofpancreas and duodenum does not produce it; nor is it due t o theloss of the pancreatic juice in the intestine. The usual theoryadopted is that i t is produced by the loss of an internal secretion,formed nornially in the pancreas and distributed by the blood t)oDiamarc, Abstr., 1907, ii, 285.On the amount of glycogen in the livers oftliest: fislies, aiid its relationship to fats, see Bottazzi, iDid., 979256 ANNUAL REPORI’S ON THE PKOGKESS OF CHEMISTRY.the tissues, where it influences carbohydrate metabolism in someway. The little groups of epithelium cells scattered through theconnective tissue of the organ, looking like it number of ductlessglands in miniature and called the Islets of Langerhans, werea t one time considered to be the site of the formation of theinternal secretion; it has, however, been shown that the islets areonly phases in the life-history of the ordinary secreting acini, andso it is difficult to accept this exclusive view.LQpine’s idea was that sugar destruction o r glycolysis was accom-plished by the pancreatic internal secretion in the blood, andtherefore when the pancreas was removed glycolysis ceased andsugar accumulated in that fluid.This was regarded as improbablefrom the first, for metabolic processes do not occur in the circulat-ing fluid any more than respiratory processes do; it has since beenabundantly disproved. It may, however, still be that the activeprinciple of the pancreatic internal secretion stimulates theglycolytic action of the tissue cells; and 0. Cohnheim publishedsome experiments which appeared to prove this, for he found thatextracts of pancreas, added to muscles, facilitated what did notoccur markedly in its absence, namely, a combustion of sugarthere.Unfortunately, subsequent observers failed to obtain thesame result, so that we are still in the dark as to th.e exact modusoperandi of how it is that the pancreas exercises this most importantr81e. During the last year, however, E. W. Halls6 has confirmedCohnheim’s statemenbs, and this observer states that the alcoholicextract of boiled pancreas will act similarly; the substance whichacts as the co-operator in glycolysis is precipitable by phospho-tungstic acid.Bang 87 has included pancreatic diabetes among the conditionsin which he has investigated the amount of liver-diastase. Hefinds that the amount of ferment is not much greater than in thenormal condition, and therefore concludes that pancreatic diabetesis not due to an increased conversion of glycogen into sugar;glycogen formation is, in fact, either prevented or greatly lessened,and so this form of diabetes contrasts with that produced bypuncture and other nervous agencies.So far all observers are in agreement, o r only manifest differencesof opinion on minor points or in the explanation of the observedfacts. Pfliiger’s recent article 88 therefore came as a bomb-shellinto the physiological camp when he announced his completedissent from everybody else.H e found that in frogs extirpationof the pancreas produced fatal diabetes; that death or diabeteswas not prevented by the transplantation of the pancreas fromB(i Abslr., 1007, ii, 369. b7 Loc. cit. bY Abstr., 1907, ii, 639PHYSIOLOGICAL CHEMISTRY.257aiiot,her frog into the one from which the organ had been removed;that extirpation of the duodenum or complete separation of theduodenum from the pancreas produced equally severe diabetes,even although the pancreas was not interfered with in the least,and finally that corresponding results were obtained also in dogs.His conclusion is that the internal secretion theory of pancreaticdiabetes is a myth, and that the condition is produced solely bynervous disturbances.Those who know Pfliiger’s love of polemics will, even withoutreading his papers, be able to imagine their style. It, may be thaths has discovered serious flaws in the methods of those who haveobtained different results; it may be that he is right in his presentconclusions; on the other hand, he may be wrong; only the futurecan show.Whatever may be the result of this controversy, another hasbeen finally settled during the year? and that is that the treatmentof diabetes by secretin, recommended by Moore and his col-leaguesF9 is of no avail.903.Administrution of Yh1oridzin.-Many poisons produce tem-porary ,glycosuria, but the most interesting and powerful of theseis phloridzin. The diabetes produced is very intense,Fhloridzin is a glucoside, but the sugar passed in the urine istoo great in amount to be accounted for by the small quantity ofsugar in the drug; and, further, a derivative of phloridzin, whichis free from sugar and called phloretin, produces the same results.It is, however, stated by Bang, Ljungdahl, and Bohmgl that inphloridzin diabetes there is little or no increase in the liver-diastase,whereas there is an undoubted increase of this ferment in phloretindiabetes.I feel doubtful whether this can be considered t o provethat the mechanism in ths two cases is different.These drugs produce diabetes in starved animals,gZ or in those inwhich any carbohydrate store must have been got rid of by theprevious administration of the same drug. This form of diabetesis therefore analogous to those intense and serious forms ofdiabetes in man in which sugar is excreted in spite of abstinencefrom carbohydrate food, and must therefore be derived fromprotoplasmic metabolism. A striking feature in phloridzin diabetesis the absence of an increase of sugar in the blood; it is glycosuria89 Abstr., 1906, ii, 186, 787.90 Bainbridge and Beddard, ibid., 786 ; N.B. Foster, Abstr., 1907, ii, 189 ; Dakin91 Compare A b s t ~ . , 1907, ii, 900.92 Pfluger (ibid., 1908, ii, 52) states that hunger does not cause by any meansIn the latter animals,and Ransom, ibid., 189.a complete disappearance of glycogen either in dogs or frogs.the amount may even increase during the winter’s abstinence from food.REP.-VOL. IV. 2.58 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.without glyczmia. Moreover, if the phloridzin is directly injectedinto one renal artery, sugar rapidly appears in the secretion ofthat kidney and later in that of the other kidney. The sugar inthis condition must be formed by the kidney from some substancein the blood, and it is a t present unknown what that substanceis.It is probably protein in nature, and most proteins contain asmall amount of a carbohydrate radicle (glucosamine); but thelarge amount of urinary sugar is with difficulty accounted for inthis way. The mucins and mucoids of the body contain the samecarbohydrate substance in much greater quantity, though i t isdoubtful whether they participate to any great extent in generalmetabolism. Bywaters93 surmises that the blood contains one ofthese complex proteins, which he terms sero-mucoid, but again wehave the difficulty that if this is the means of sugar transport thequantity of sero-mucoid in the blood is very sma11.94 It is nowgenerally admitted that the sugar originates, not from any carbo-hydrate linked to the protein, but through the intermediation ofcertain amino-acids.The fact that the nitrogen of the urinegenerally rises in amount is another indication of protein break-down. Graham Luskg5 has made a special study of the dextrose:nitrogen ratio, and finds that in phloridzin diabetes, after all thecarbohydrate store of the body has been got rid of, it is a constantone, namely, 3.65: 1. We have here a proof that in this form ofthe disease the sugar has an exclusively protein origin; indeed,nearly 50 per cent. of the protein molecule must be converted intosugar. I f the same ratio occurs in a man (on a diet containingno carbohydrate) or any approach to it, practitioners may be quitecertain they are dealing with a serious case, and that a rapidlyfatal issue in such case may be foretold with certainty has alreadybeen exemplified in Lusk’s hands.The amino-acid which of all others acts as the intermediarybetween protein and sugar is alanine.The relationship of alaninega Abstr., 1907, ii, 105.94 Quite a number of papers have appeared during the gear on the question of thestate of sugar in the blood. Edie and Spence (Abstr., 1907, ii, 154) state that i t ispresent (1) in the free state, (2) in combination with protein and lecithin, (3) as apolysaccharide ; according to them the corpuscles contain no sugar. Asher andEoseufeld (ibid., ii, 279) state that all the sugar, like the sodium chloiide, is free.This conclusion, which is based on diaIysis experiments, is criticised by Ptliiger(ibid., ii, 367).LQpine and Boulud (ibid., ii, 562) consider i t is present largely inthe form of glucosides, from which it can be liberated by invertase, emulsin, &c.Embden, Liithje, and Liefmann (ibid., ii, 889) discnss the influence of externaltemperature on the blood suga ; cold increases, and warmth diminishes it, Coldlessens the hepatic glycogen, and the increase of blood sugar is regarded as anincreased supply on its way to the muscles, the seat of combustion.y.j Abstr., 1905, ii, 187PHYSIOLOGICAL CHEMISTRY. 259to the carbohydrates is a near one, for if the hydroxy- is substitutedin its molecule for the amino-group we get lactic acid. It has beenfound that feeding rabbits with alanine leads to glycogen formationin their livers and to the passage of lactic acid into their urine.Another protein cleavage product, aspartic acid, acts in the sameway, and this also is easily intelligible on chemical lines, for ifaspartic acid loses carbon dioxide it is converted into lactic acid,and it is no great step Trom this to sugar.Glaessner and Pick96 corroborate these views in experiments onrabbits suffering from phloridzin diabetes ; the giving of alanineand glutamic acid caused most sugar t o appear, leucine and glycineless, and asparagine none.They found also that if the animalswere fasting no amino-acid led to any increase of sugar; obviouslyin the fasting animal the amino-acids given were retained and notimmediately broken up. Another interesting point they madeout in these experiments was that the liver of phloridzinisedanimals given subcutaneously to other animals produced glycosuriain the latter.In this relation I must allude to some work by K. Gr~be.~7He perfused the liver of tortoises with Ringer’s solution, to whichhe added various sugars; galactose and lxvulose produced a smalland dextrose an enormous increase in the hepatic glycogen. Othersugars gave a negative result, and so also did certain amino-acidsof which he used glycine, alanine, and leucine. The negativeresult with alanine cannot be considered a very serious objectiont.0 the views I have advanced in the preceding paragraphs, for nodoubt i t is explained by the fact that in the tortoise metabolismis very sluggish, although probably not different in kind from thatseen in warm-blooded animals.,4 cidcenzia.-This question, so closely related to diabetes, is thelast one I shall discuss. The words acidosis and acidsmia havealmost entirely replaced the word acetonzemia in medical writingson diabetes. It has been proved that neither acetone nor itsparent substance acetoacetic acid is the actual cause of diabeticcoma. Both of these originate from certain fatty acids, of whichthe most toxic is /3-hydroxybutyric acid or its amino-derivative.This undoubtedly arises from fat, from which it appears that indiabetes there is not only an inability to oxidise carbohydrate, butalso to oxidise fat with the usual final products, carbon dioxideand water. In these cases the alkalinity of the blood, and also itscarbon dioxide, are reduced, and the ammonia of the urine isincreased. This indicates an attempt of the body t o neutralise thepoisonous acid. Ammonia production is the physiological remedyw.i rfbstr,, 1907, ii, 41. 97 Ibid., 565,s 260 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.for increase of acids, or, to put it more correctly, less of theammonia which results from katabolism is converted into urea. Oflate years, however, pathologists have seen reason to doubt whetheracidzemizt is constantly present in diabetes, or even in diabeticcoma; no doubt there are other factors t o be considered also, andnumerous papers are being continually presented on the subject ;I cannot say that any of those which appeared last year throwany important new light on the subject, and the only one I shallrefer to is by Allard,98 which deals with the subject from thequantitative standpoint ; systematic observations on the course ofthe excretion of acetone, P-hydroxybutyric acid, &c., have hithertobeen lacking. Allard’s estimations do not go very far, and hewisely abstains from drawing conclusions, but this is the sort ofwork which will have to be performed before pathologists are ableto discuss logically their views on the subject.4. Administrution of Adrenaline.-This is a drug which pro-duces so many interesting results that a t least a mention of thefact that it also produces glycosuria is demanded. A t present,however, but little is known of the way in which the drug causesthis result. Adrenaline diabetes is one in which glyczmia accom-panies the glycosuria; i t largely depends on t.he amount of carbo-hydrate in the food, but, as in diabetes generally, there is anincreased decomposition of protein material leading to an increaseof the urinary ammonia and urea. Herter thought the drugoperated through the pancreas, but Noel PatonQQ states that thisis incorrect, because in birds without a pancreas (in these animalsextirpation of the pancreas does not produce diabetes in itself) thedrug causes glycosuria as effectively as in normal animals. Under-hill and Closson100 were unable to confirm Paton’s statementxrespecting the effect of the drug on protein metabolism; they regardthe condition as essentially nervous and consider that the poisonacts on the sympathetic, so preventing carbohydrate storage orleading to a depletion of any carbohydrate store already present.W. D. HALLIBURTON.03 Abslr., 1907, ii, 639.loo Ibid., 1906, ii, 787.O9 Ibid., 1905, ii, 106

ISSN:0365-6217    

DOI:10.1039/AR9070400226

出版商:RSC    

年代:1907

数据来源: RSC

摘要:

AGRICULTURAL CHEMISTRY AND VEGETABLEPHYSIOLOGY.THE record of the year includes no notable discovery nor anypaper that is likely to be reckoned in the future as of fundamentalimportance ; in several directions, however, good progress has beenmade, although, as the subject opens up, it is only to disclose itsincreasing complexity. Agricultural chemistry is essentially aborder-line science, dwelling on the confines of chemistry andphysics, botany, and physiology alike, touching these subjects alsojust where they are most difficult and obscure. The chemistry of thegrowing plant and of the feeding animal is the chemistry of theproteins and the carbohydrates, of enzyme action, and of the variedfunctions of the cell, whilst the study of the soil a t once leadsto some of the most difficult problems of solution, and of the inter-action of molecular and chemical forces which take place in thethin films surrounding the soil particles.So&? Bacteriology.Considering first the soil, the part played by the organismscontained therein assumes every year a greater importance; i tbecomes increasingly evident that plant production in the openfield, and the effect of fertilisers and even of cultivation, aredetermined by the nature of the soil flora and the repression orencouragement of particular groups of micro-organisms.The freeorganisms in the soil that can fix atmospheric nitrogen continuet o receive considerable attention, and the chief conditions of theiractivity-a supply of oxidisable carbohydrate, from which theymay derive the necessary energy, and the presence of calciumcarbonate to neutralise the acids produced-may be regarded asestablished; i t is the magnitude of the part played by Azotobacterand its congeners, under natural conditions, that remains to bedetermined.A. Koch and his colleagues a t Gottingenl showthat the addition of dextrose, sucrose, soluble starch, or straw tosoil brings about an increase in the amount of nitrogen i t contains;Absh., 1908, ii, 56262 ANN'IJAL REPORTS ON THE PROGRESS OF CHEMISTRY.the best effect was obtained by a single application of 2 per cent.of dextrose, when 8 to 10 milligrams of nitrogen were fixedfor each gram of sugar added. They also showed that the nitrogencompounds formed by the Azotobacter, the chief organism con-cerned, were easily nitrified; as a consequence, when sugar wasadded to soil in pots in which successive crops of oats andbuckwheat or sugar beet were grown, the nitrogen fixation induced bythe sugar became evident in an increased yield.The first crop of oatswas reduced, the unchanged sugar acting injuriously on the growingplant, but in the following year the yield of buckwheat or beet wasmuch increased, being nearly trebled where 4 per cent. of sugar hadbeen added. A t the end of the experiment, the sugar-treated soilwas also found to have been enriched in nitrogen. That the depres-sion of the first crop was due to the injurious effect of the unalteredsugar was shown by another experiment, in which the soil, afterthe addition of the sugar solution, was kept in an incubator forfour weeks.Oats were then sown, which yielded more than doublethe amount of dry matter that was obtained in the check experi-ments, where the soil received no sugar. These experiments con-stitute the first direct experimental demonstration that A zotobact ercan play a practical part in provision of nutriment for the higherplants.H. R. Christensen2 has dealt with the importance of calciumcarbonate and the phosphates in the nutrition of Azotobacter.He showed that the occurrence of Azotobacter in various soilsstands in close relationship to the amount of calcium carbonatein the soil, exceptionally active soils always possessing an alkalinereaction, which confirms the observations of S.F. Ashby on theRothamsted soils.3 He even considers that the growth of Azoto-bacter will form the most trustworthy evidence that can be obtainedof the presence of traces of calcium carbonate in soils. J. F.Lipman 4 also used A zotobact er as a test of the state of the mineralconstituents of the soil, and reaches much the same conclusionsas Christensen, whilst Wilfarth and Wimmer found thepresence of phosphoric acid essential.As regards fixation of nitrogen by the nodule organisms of theleguminosze, no new step can be reported; various preparations ofthe organism are being widely used* in a practical way for theinoculation of seed or soil before a leguminous crop, although thebest way of preserving the cultures in an active condition hasCentr.Bctkt. Par., 1907, 11, 17, 109, 161, 378, 735.Rpport New Jersey Agric. Exp. Station, 1907.See Remy, Centr. Bakt, Par., 1907, 11, 17? 661,9 J. Agrie. Sci., 1907, 2, 35.Abstr., 1907, ii, 809AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 263not yet been settled? But, although inoculations may be of thegreatest possible benefit in introducing the appropriate organisminto soils which have never previously carried the leguminouscrop in question, such soils are exceptional, and it is not yetdemonstrated that there is any return for the ihoculation ofordinary cultivated land, It is uncertain whether more activeraces of the clover organism, for example, can be distinguished,and, further, i t is uncertain if such improved races, when intro-duced into ordinary soil swarming with kindred organisms, cansurvive the competition that results, so as to produce any permanenteffect upon the crop.As regards nitrification, perhaps the most important of thebacterial processes in the soil, Kaserers reports the isolation ofanother bacterium, B.nitrator, which forms nitrates from ammoniain a single operation. Hitherto, no nitrifying organisms havebeen detected other than those first distinguished by Waringtonand then isolated and described by Winogradsky, Nitrosmonas andNitroscoccus, which oxidise ammonia t o nitrite, and the Nitro-bacter, which completes the change t o nitrate. Muntz and Lain6 9have been studying the nitrification process on a large scale toascertain if the old nitre beds could be so far improved as t obecome practical sources of nitrate, supposing the conditions ofa century ago were to recur and France were again cut off fromany external supply of Chilian or Indian nitrate.Miintz obtainedthe most intensive nitrification when a weak solution of ammoniumsulphate percolated through a layer of some medium offering alarge surface, peat proving the most effective when an excess ofcalcium carbonate was maintained. The inhibiting effect oforganic matter on nitrification does not hold for the humic com-pounds of peat. A strong solution of ammonium sulphate cannotbe nitrified, but by repeatedly adding further small amounts toa solution that has already been oxidised, and passing it againthrough a nitrifying bed, the concentration of the calcium nitratecould at last be raised to about 44 per cent.Some little time wasnecessary before the beds reached this efficiency, since the nitri-fying organisms only gradually become habituated to working insolutions of such a concentration. In view of the rapid develop-ment of the electrical processes for making nitrates, it is -improb.able that Miintz’s improved nitre beds will ever be required.Perhaps the most interesting question in soil bacteriology whichhas of late been opened up, is concerned with the increased pro-ductiveness shown by soil that has been subjected to some processR. G. Smith, Ahstr., 1907, ii, 498.Bull. Soc. d’encourugeinent pour 2’Industrie Nntionnte, 190’1, 109, 951.8 Ibid., 381264 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRP.of partial sterilisation, such its heating to the temperature ofboiling water, or treatment with volatile antiseptics like carbondisulphide o r toluene.The facts have been disclosed in a moreor less accidental fashion by various workers during the last tenyears or so, 'but it is only just lately that they have attractedmuch attention, or have been seen to possess any general signifi-cance. Various papers on the \subject appeared during 1907(Heinze,lo Kochll), including one by F. V. Darbishire and E. J.Russell,l2 which traverses the whole ground very thoroughly. I ncontinuance of the work of these authors on the rate of oxicla-tion in soiIs,13 they were led to observe that soils which had beenheated to looo, or treated for a time with volatile antiseptics,always showed a higher rate of oxidation than the same soilsuntreated. As they had previously established an interdependencebetween the rate of oxidation and the fertility of a soil, theyproceeded to test the effect of such treatment upon the productive-ness of soils by means of experiments in pots.The soils were eitherheated for two or three hours to a temperature of 90-95O, or treatedin their pots for about a week with a small quantity of carbondisulphide, toluene, or chloroform, after which they were spreadout in thin layers until all trace of the antiseptic had volatilised;no trace of the antiseptic could be detected by any of the teststhen applied. Various crops were grown in the pots, and in allcases the treated soil yielded a greater weight of dry matterthan the untreated soil, the increase being generally from 10t o 40 per cent., but occasionally as high as 70 to 90 per cent.The beneficial effect of the treatment was also seen when a secondcrop was taken without further disturbance of the soil, but itdid not extend t o the third crop.Not only was the dry matterincreased, but it was, as a rule, richer in nitrogen, phosphoricacid, and potash, so that the crop always removed larger amountsof these fundamental nutrients from the treated soil.The result of heating the soil was even more marked; exceptin the case of certain leguminous plants, the yield of the heatedsoil was generally doubled or even trebled, and again the effectpersisted to the second, and sometimes to further crops.It is impossible to explain these results from a purely chemicalpoint of view, for, even if the heating might be supposed to rendermore available the store of plant food in the soil, no correspondingaction could be attributed to the vapour of toluene or chloroform.It was demonstrated that the soils were not completely sterilisedby the treatment, and the mold tenable explanation is that theAbstr., 1907, ii, 388, 502, 572.11 B i d . , 647.13 Ann, Report, 1905, 251. $2 J, Agric. Sci., 1907, 2, 305AGRICULTURAT~ CHEMISTRY AND VEGETABLE PHYSIOLOGY. 265partial sterilisation exercises some selective action on the groupso l bacteria in the soil, destroying some which are unfavourable tothe growth of the plant, and thereby giving other beneficial forms,like the oxidising bacteria, a greater scope.One of Darbishire andRussell’s experiments is rather significant in this connexion ; theyfound that if they watered the heated soil with ordinary well-water,i t lost some of its superiority over the untreated soil, thus indicatingthat the beneficial rearrangement of the original soil flora broughtabout by the partial sterilisation can only persist when the soilis watered with sterile water introducing no new forms.With this work of Darbishire and Russell’s may be connectedan investigation by 0. Rahn 14 on the effect that drying soil a t theordinary temperature has on its bacteriological properties.Soilwhich had merely been aIlowed to dry was found to induce greaterbacteriological changes, as, for example, production of acid in dex-trose solutions, production of carbon dioxide in sugar solution con-taining calcium carbonate, formation of ammonia in urea orpeptone solutions, than did the same soil after storage in a moistcondition. These effects were most manifest with a rich gardensoil, but it was not settled whether they were to be regardedas accelerations due to drying, or depressions brought about bystorage in a moist state. The number of the bacteria (growingupon gelatine) in the soil was always diminished by drying, andthe author considers that his results show the effects were due tosome substance formed in the soil by drying, which is soluble, notdecomposed by boiling its solution, and not of the nature of anordinary plant nutrient.Experiments on the effect of a pre-liminary drying of the soil on mustard in pots were not conclusive.The susceptibility of the soil to changes of this kind is a questionstill open to a good deal of elucidation, but i t already promisesresults which may attain considerable practical importance ; mean-time, it also serves to emphasise the necessity for caution in draw-ing conclusions from any experiments on soil, when what is appar-ently so small a disturbance can bring about such a radical changein its productiveness.Sod Ch emistry.I n this section of our subjkct there is nothing novel to report,although Whitney and his colleagues of the Division of Soils(U.S. Department of Agriculture) have issued several bulletins,l5in which they continue t o develop their somewhat remarkabletheory of the functions of soil and fertilisers, a theory which hasl4 Cmtr.Bakt. Par., 1607, 11, 20, 38.l5 See particularly Eulletias Nos. 36, 40, qnd 47266 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY,found no acceptance, nor much consideration, among Europeanchemists .I6Briefly, Whitney’s theory is that soils become infertile throughthe accumulation of toxic substances excreted by the roots of crops,and that fertilisers act, not by directly feeding the plant, butby in some way destroying or putting out of action these toxicexcretions. The experiments brought forward in support of thistheory are chiefly made with wheat seedlings in water cultures,the seedlings being from six to twenty days old, and thereforestill drawing their nutriment from the endosperm.The reportsgo to show that the growth of such seedlings in distilled wateris injured by the addition of an aqueous extract of certain soils,but that the injurious effect of the extract can be removed by a pre-liminary filtration through finely-divided carbon, shaking up withferric hydroxide or calcium carbonate, and, as a rule, by boiling.Other experiments showed that water in which such seedlings havebeen grown for a time acts injuriously on the growth of a newbatch of seedlings, but that filtration through carbon, &c., as before,restores the water in which the seedlings have been grown to anormal condition suitable for renewed growth.Distilled watercontaining very small amounts of such plant products as neurine,guanidine, coumarin was also shown t o be hurtful t o the develop-ment of the seedlings, but was again improved by the treatmentdescribed before. Many questions suggest themselves in readingthese interesting reports and the speculations they give rise to, butcriticism is as yet impossible; the data supplied afford no means ofestimating the magnitude of the experimental error, which is knownto be great in experiments of this kind, and the experiments them-selves are never pushed to the point of becoming really critical ofthe theory, the authors seeming to be content to multiply results(( which may be explained by supposing,” o r are ‘( in accord with theassumption upon which the experiment was made.” Here, in Europe,we must suspend our judgment until we receive a more criticalversion of the work.The perennial question of the most suitable solvent to use forthe determination of the ((available” mineral plant food in thesoil continues to receive attention.E. A. Mitscherlich 17 selectedwater saturated with carbon dioxide, which substance he regardsas the main secretion of the plant’s roots, and the effective solventunder ordinary soil conditions (see also Stoklasa, dzc.18). He thenproceeded systematically t o the examination of one or two soilswith the view of determining the effect of the concentration ofl6 See, however, Pouget and Chouchak, Compt.rend., 1907, 145, 1200.l7 Landw, Jahrbucher, 1907, 36, 309, l8 Abstr., 1907, ii, 717ACXRICULTURATA CHEMISTRY AND VEGETART,F, PHYSIOLOGY. 267the carbon dioxide in the solution, of the duration of the action,and of temperature, so as to arrive at the probable error attachingt o estimations of this method. It is noteworthy that the tem-perature factor is considerable for the potash and nitrogen, butnot for phosphoric acid or lime, although it has hitherto beenneglected in considering these various methods of extraction ofweak solvents. No attempt was made by Mitscherlich to corre-late his results with the behaviour of the soils in the field; this,however, was the prime object of A. de Sigmond,lD who has exam-ined Hungarian soils by an entirely different method.de Sigmondstarted from some experiments of Schloesing’s,20 who showed thatil a series of samples of soil be attacked by very dilute solutionsof nitric acid, the strength of which increases by steps, the amountof phosphoric acid dissolved increases at first with the strengthof the nitric acid solution, then remains constant for a time, and thenbegins to rise again. This second increase, according t o Schloesing,marks the point a t which the nitric acid becomes more than strongenough to dissolve all the ‘‘ available ” phosphoric acid, so thatit then begins to attack the more insoluble compounds presentin the soil. de Sigmond generally discusses the results obtainedby this method, which was thus tried for the first tJme on a largescale, and obtained a considerable agreement between them andthe behaviour of the soils towards phosphatic fertilisers, as judgedby a series of field and pot experiments, which are also reported.Another question which dates back to the earliest days of agri-cultural chemistry, the withdrawal of ammonia from its com-pounds, and its retention by the soil, has been re-examined duringthe year by A.D. Hall and C. T. Gimingham.21 These authorsfound that the action was always one of double decomposition,either with the zeolitic double silicates of the soil, ammoniumbeing withdrawn and an equivalent amount of calcium, mag-nesium, potassium, or sodium taking its place in the solu-tion, or with humus (calcium humate), in which case anequivalent amount of calcium again replaced ammonium in thesolution. No measurable amount of adsorption of the salt, asa whole, or of selective absorption of the base, so as t o leave thesolution acid, was observed, even when the solutions wereevaporated at the ordinary temperature in a current of air, orexposed to the action of a stream of carbon dioxide.The authorsgive an empirical formula connecting the amount of change with theconcentration of the ammonium salts in the solution when theamount of clay in equilibrium with the solution is in excess, butJ9 Abssty., 1907, ii, 717. 2o lbid., 1899, ii: 449.21 Trans., 1907, 91, 877268 ANNUAL REPORT8 ON THE PROGRESS OF CHEMISTRY.do not establish any theoretical justification for the formula arrivedat.The authors also considered the interaction of ammoniumsalts and calcium carbonate, but showed that the presence of thisconstituent affects but little the removal of ammonia from solutionby the clay and humus. They therefore regard the retention ofammoniacal fertilisers by the soil as due to clay and humus withoutthe preliminary reaction with calcium carbonate that is sometimesregasded as necessary.R. A. Robertson, Irvine, and Miss Dobson22 have begun a freshstudy of humic acid, which they have extracted from peat, and alsoprepared by the action of hydrochloric acid on sugar. The elemen-tary composition of the two products were compared, and, besidesdifferences in the percentage of carbon, the natural acid always con-tained nitrogen, and probably iron.It yielded fewer methoxylgroups than did the artificial acid, and, when compared as a sourceof carbon for the growth of Penicil'lium, the artificial acid wasbetter than the natural, but inferior t o glucose. S. Suzuki 23 has alsoexamined natural humic acid by hydrolysing i t with strong hydro-chloric acid ; from the products, he isolated alanine, leucine, aspar-tic acid, and small quantities of proline and other amino-acids.Several reports on the analysis, chemical and mechanical, of aseries of English soils have been published during the year, and, asthe analyses have been carried out on a uniform system, there issteadily being accumulated a mass of data for a general chemicalsurvey of the soils of our country.C.M. Luxmoore 24 described the composition, mechanical andchemical, of one hundred samples of soil and subsoil from Dorset-shire, the soils being derived from each of the tertiary andsecondary formations between the Bagshot Beds and the LowerLias ; F. W. Foreman 25 dealt with soils from Cambridgeshire, gene-rally derived from the same formations as those discussed byLuxmoore, and S. F. Armstrong26 attempted to correlate the com-position of a number of meadows and pastures in the easterncounties with the chemical and botanical coniposition of the herbage.Soil Physics.The physics of the soil is, perhaps, a t the present time the mostneglected branch of agricultural science, yet it ought to be veryattractive to any investigator, if it were only for the bearing ithas on the practical operations of cultivation and managementof the soil, which are of such prime interest to the working farmer.See also A.J. van Schermbeck, Abstr.,22 Abstr., 1907, i, 894.z3 Bulb. (7011. Agr. T6ky6, 1907, 7, 513.25 J. Ayric. Sci., 1907, 2, 161.1907, ii, 648. BJ Beport, Reading University College,2ti Ibid., 283AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 269During the past year few papers bearing on this subject haveappeared, nor has any new line of inquiry been opened up. VonSeelhorst and his colleagues at Gottingen 27 have continued theirstudies of the effects of variation in the water content and tempera-ture of the soil on the composition and yield of various crops, theexperiments in this case being made on oats and spring wheat.R.S. Vinson and E. J. Russell28 gave an interesting series oftemperature readings to illustrate the well-known fact that thebottoms of valleys are colder than the slopes on either side. Theresults agree with the usual explanation that the cooled air flowsdown the sides and accumulates in the bottom of the valley, butthey also indicate that the actual river bank is warmer than landa little further back from the water, the rise in temperature beingparticularly marked on any piece of land more or less surroundedby water.Another perennial problem, the flocculation or coagulation bymeans of salts of turbid liquids, such as suspensions of clay inwater, has again been dealt with by A. D. Hall and G.G . T.Morisoi~.~~ These authors have endeavoured to obtain quantitativemeasurements by using a constant amount of a graded kaolindiffused in a constant volume of water. The effect of varioussalts, &c., on jars filled with such a turbid medium were estimatedby matching them against a standard series in which the floccula-tion was brought about by regularly increasing amounts of calciumnitrate. The authors show that the amount of material flocculatedwas proportional to the amount of flocculating salt added up t oa certain point, above which any increase of salt produced nofurther effect; there was no adsorption of the salt, nor did floccula-tion involve any growth or permanent aggregation of the fineparticles of the suspended matter.Conductivity measurements,while flocculation is going on, indicated that no perceptible changeoccurred in the amount of salts in solution. The acids were the mosteffective flocculators, and aluminium salts were almost equally eff ec-t h e . Calcium and barium were less than half as effective, mag-nesium came a little below calcium, potassium had only about one-fifth the value of calcium, and sodium only about half that ofpotassium, equivalent for equivalent. The nature of the acidradicle had an influence on the flocculating power of the salt, theorder being hydrochloric, nitric, sulphuric, acetic (the chloroaceticacids had the same value as acetic acid itself); the same compara-tive order held for the salts as for the free acids. Oxalic andtartaric acids were feeble flocculators; citric acid, glycine, or"7 J.Landw., 1907, 55, 233. 28 J. Agric. Sci., 1907, 2, 221.Ibid., 2442'90 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.phenol were without action. Soluble hydroxides such as causticsoda, potash, or ammonia opposed flocculation ; calcium and bariumhydroxides gave, however, positive effects, but much below thoseshown by their other salts, the flocculating effect of lime in practicebeing due to the formation of calcium bicarbonate, which is a veryeffective salt. Many substances, for example, bauxite and hydratedferric oxide, do not form true suspensions in water, which propertythe authors regard as conditioned by the presence of double silicates,which hydrolyse and yield a little soluble alkali on contact withwater.On this theory, flocculation is brought about by the neu-tralisation or throwing back into combination of the free alkali,although any final clearing up of the subject must be preceded byan explanation of the Brownian motion, which characterisesparticles in true suspension in a turbid liquid.Chemistry of the Growing Plant.1. Nutrition.-Although nothing very striking is to be reportedin connexion with the nutrition of the plant, Fenton's synthesisof formaldehyde 30 from carbon dioxide by reduction of the aqueoussolution with magnesium should be noted as the first reduction ofcarbon dioxide that has been accomplished a t the ordinary tempera-ture. This may be regarded as a step forward, although thesynthesis is not of a type which can be imagined as taking placewithin a plant's cell; still, the evidence seems t o be increasingthat formaldehyde forms one of the steps in the natural processof photo-synthesis. G.Kimpflin 31 detected formaldehyde in theleaf of Ayave by injecting a solution of sodium hydrogen sulphitecontaining p-methylamino-m-cresol, which forms a red precipitatewith formaldehyde, but not with other aldehydic compounds.Although the function of the various mineral constituents ofthe plant is very far from settled as yet, a number of contributionsto the subject have been made during the year. H. S. Reed32 haseliminated some of the difficulties inherent in the problem by work-ing with a l p like Spirogyra in water cultures, from which thepotash, the phosphoric acid, or other constituent in question couldbe-omitted as desired.In this way, he observed that, in the absenceof potash, all starch formation was suspended, and the granulesoriginally present in the cells gradually disintegrated and disap-peared. The lack of phosphoric acid proved very injurious, espe-cially to the reproduction of the cells; there was no mitotic divisionof the nucleus, and there was an abnormal formation of cellulose.30 Tram,, 1907, 91, 687. Abstr,, 1907, ii, 289,82 Ann. of BOta7L?, 1907, 21, 501AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 27 IIn the absence of calcium salts, new cell walls were imperfectlyformed, and the production of cellulose ceased, whilst miignesiumappeared t o be essential t o the activity of the chloroplasts, sincein its absence no oil globules were to be found, and the chlorophyllassumed a yellow colour. The latter observation is interesting inconnexion with the important work by R.Willstatter 33 and his col-leagues on chlorophyll and its derivatives, which they have shownt o be compounds of magnesium, without any iron.D. Lienau and A. Stutzer,% experimenting with oats, found thatphosphoric acid promotes thickening of the cell walls, which,however, was diminished by potash and nitrogen. In consequence,phosphoric acid most promoted the stiffness of the straw. Theseresults, as regards potash, are hardly in accord with former obser-vations, or with the known function of potash to promote carbo-hydrate formation.The long-debated question of whether the roots of plants secretean acid, which aids in the nutrition of the plant by effecting thesolution of the mineral constituents of the soil, has been thesubject of further investigation.Kunze 35 reviews the evidenceagain, and concludes that only carbon dioxide is excreted. Hedoes not, however, regard this as capable of bringing enoughmaterial into solution, and shows that the acid excretion from themycelium of fungi in the soil is more effective.Schreiner36 brings evidence t o show that the roots of seedlingsboth excrete acids and possess oxidising powers, but no argumentas t o plant roots generally can be drawn from the behaviour ofthe roots of autotrophic seedlings. Stoklasa and Ernest 37 alsoregard carbon dioxide as the effective natural solvent of mineralsin the soil, and have been continuing their investigations on theamount that is excreted by plant roots and by micro-organismsin the soil.Under natural conditions, they obtain 15 milligramsof carbon dioxide in twenty-four hours from a kilogram of the soilthey worked with.Work continues t o be reported on that much-debated question,the stimulus t o plant production brought about by minute tracesof metallic salts and other substances whicb in higher concentrationsact as poisons. Despite the numerous investigations on the subject,for example, by Raulin, by Loew and his pupils in Japan,% byJ. A. Voelcker in this c0untry,3~ the prime fact of stimulus byminute traces of poison cannot be regarded as established.In-creased growth has, doubtless, been observed t o follow the applica-83 Abslr., 1907, i, 69, 71, 784.B7 Zeitsch. Zuckcrind. Bohm., 1907, 31, 291.3b Ibzd.34 Ibid., ii, 47.36 Abstr., 1907, ii, 715.Iti Ann. Report, 1906, 257,Jahrb. fur. Wiss. Bot., 1906, 357272 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.tion of such substances to the soil, but, as may be seen from theeffects of antiseptics, previously reported, the soil is excessivelycomplex and its equilibrium is easily disturbed. Hence it is byno means safe to cnnclude that any increased growth followingthe application of a manganese salt, for example, is due t o thestimulus of the manganese to the plant. Kayser and Marchand 40have studied the effect of small additions of manganese salts t oalcoholic fermentations.They find that the start of the fermenta-tion i3 sometimes checked by the presence of manganese, but thateventually higher proportions of alcohol, glycerol, and acids are pro-duced from a given weight of sugar. Yeasts that have been habituatedto comparatively strong solutions of manganese salts by growingin solutions of gradually increasing strength become particularlyactive, and will both induce a more rapid fermentation and pushi t further, especially if a small quantity of manganese salt ispresent in the fermenting liquid. Bertrand 41 applied manganesesulphate a t the rate of 50 kilos. per hectare to land on which wheatwas sown, and obtained an increase in the total crop of 22.5 percent., the corn being raised 17.4 per cent., and the straw 26 percent.Here, again, there is no means of deciding whether theapplication of any other soluble sulphate might not have beenequally effective by bringing into solution some of the dormant basesof the soil. G. Salomone $2 and S. Uchiyama 43 report very similarresults, in which even manganese dioxide exerted a beneficial influ-ence on crops in the open field. A. Amos4.‘ attacked the problemfrom a different point of view. Various preparations of copper (ofwhich the most widely used is Bordeaux mixture, prepared by pre-cipitating copper sulphate solution with lime 45) are sprayed on theleaves and act as fungicides, but they are also credited with bringingabout a longer life of the leaf, and an increase of crop, when no fun-goid disease attacks the plants.Flowers of sulphur are dusted on t oleaves for the same purpose. To ascertain if these substances actedas stimulants to the processes carried on by the leaf, Amos com-pared the rates of assimilation of two leaves upon the same plantbefore and after one of them had been treated with the fungicide,using Brown and Escombe’s apparatus for the measurement ofthe rate of assimilation. The only result of the treatment withthe fungicide was such a falling off in the rate of assimilationas might be expected from the inevitable blocking of the stomata,nor was any indication obtained that the activity of the leaf was40 Abtr., 1907, ii, 288, 383, 903.#l Abstr., 1907, ii, 982; also W.van Dam, ibid., 649.43 Bull. Cent. Exp, Sia. Japan, 1907, 1, 37.44 J. Agric. Sci,, 1907, 2, 257.J1 J. d’dgric. Pratzque, 1906, 42.4s Pickering, Tram., 1907, 91, 1988AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 273maintained to a greater age as a consequence of the treatment. Theexperiments were made with the leaves of the vine, and hop, andthe artichoke (Helianthus tuberosus), for which plants values ofthe rate of assimilation had not previously been obtained.2. Plant Conatitucnts and Changes of Composition durkqGrowth.-During the year, T. B. Wood has made an important steptowards the resolution of a problem, the cause of “ strength ” inwheat flour, which has long occupied the attention of agriculturalchemists in all countries.The question was the subject of a fulldebate a t one of the meetings of the Chemistry Section of the BritishAssociation, and Wood’s papers are published in the Journal ofAgricultural Science.46 Wood considers that strength, defined as thecapacity of making large, well-piled loaves, is the outcome of twofactors, one determining the size, and the other the shape of theloaf. The size is determined by the amount of carbon dioxideevolved in the dough, and this depends on the amount of sugarcontained in the flour, together with that produced by diastaticaction while the dough is rising. The shape of the loaf is deter-mined by the consistency of the gluten, which does not dependon its composition, but on the salt content and acidity of themedium with which it is in equilibrium. Wood found that thegliadin and glutenin, of which gluten is made up, possessed thesame composition (as far as might be judged from theproducts of hydrolysis), whether they were derived from strong orweak flours.By suspending pieces of washed gluten in a seriesof solutions in which both the acidity and the salt content variedby regular increments, Wood observed that for certain concentra-tions the gluten was tough and stable, while for others it disin-tegrated and lost all coherence. When the observations were allplotted with the salt concentrations as ordinates and acid concen-trations as abscissz, a closed curve could be drawn, all point3within which represented solutions in equilibrium with the non-coherent gluten.Gluten, however, in contact with solutions repre-sented by points outside the curve remained tough and elastic.Wood has discovered various relationships between the effect ofdifferent acids and salts known or likely to occur in flour, but theprecise application of the facts to the discrimination of strong fromweak flours remains to be worked out, a method for doing whichis indicated. Little is known as yet of the nature or amount ofthe acids and salts present in an aqueous extract of flour, but theseexperiments show that they must exert a marked effect on theconsisfency of the gluten, so that in their variations a clue may befound to the abnormal behaviour of many flours. Wood also shows4ti J. Agric.Soc., 1907, 2, 139, 267.REP. -VOL. IV. 274 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.that the consistency of other proteins, for example, the curd ofmilk, is similarly determined by the acidity and salt content ofthe solution with which it is in contact, and suggests that in thisfact we have a general clue to the control of all such technicalprocesses depending upon the physical properties of colloids.Thatcher and Watkina 47 have studied the distribution of nitrogenin the different grains from the same ear of wheat, and again indifferent ears of the same variety. Their work goes to show thatt’he variations thus found among the different ears of the samevariety and between the grains of the same ear are due to nutri-tion, and are not hereditary. This result a’dds another to thearguments against the possibility of improving plants like wheatby (‘ selection ” alone.Several facts of considerable chemical interest in connexion withthe membranes forming the coats of seeds have been publishedduring the year.In the first place, A. J. Brown 48 has shown thatthe barley grain possesses a true semipermeable membrane, throughwhich water will pass freely, but not any of the salts which maybe dissolved in the water. I f , for example, unbroken barley grainis immersed in normal (4.9 per cent.) sulphuric acid, water onlypassed through the membrane into the endosperm, until the sul-phuric acid solution outside became concentrated up t o 7.6 percent. The grain also absorbed water from 18 per cent. sulphuricacid, but failed to do so from ilr solution containing 36 per cent.ofacid. The effective membrane appeared to be located in €he spermo-derm, since this layer resisted the action of 36 per cent. sulphuricacid, by which the outer layer of cells forming the pericarp wasdisintegrated. Iodine was the only dissolved substance that wasfound capable of passing through the membrane, and it seemssignificant that the substance so doing should also be one com-bining with the starch of the endosperm.C. Bergtheil and D. L. Day49 showed that the irregular and slowgermination of the seeds of Java Indigo (Indigofera arrecta) wasdue t o the preponderance of ‘(hard” seeds, formed only when theseed crop was allowed to become thoroughly ripe.These hard seedsare practically impermeable to water, owing to a thin outer cover-ing, neither true cellulose nor true cuticle, which can be removedby scratching or by steeping the seed for half an hour in concen-trated sulphuric acid, followed by immersion in water.Similar “ hard ” seeds in clovers and other European leguminousplants have been studied by Hilbner and Kin~el,~O who recommend47 Abstr., 1907, ii, 983.so Zeitsch. fiir LarLdw. ZL. Forut. FVirts., 1906, 36.A w . of Botmy, 1907, 21, 79.49 Ibid., 57AGRICULTURAL CHEMISTRY AND VEGETABLE PHYSIOLOGY. 275treatment of the seed with hot water or sulphuric acid in orderto promote germination.Amongst other papers dealing with plant constituents, one shouldbe noticed by E.Schulze,51 in which he maintains that the darken-ing of beet and other plant juices is not due to the enzymic oxida-tion of tyrosine, as is commonly supposed. The tyrosine he couldobtain from the juice of beet, potato, and dahlia tubers was toosmall in amount to account for the darkening; moreover, afterdarkening, the tyrosine was still there, and no trace of homogen-tisic acid could be detected.I n the chemistry of enzyme actions, we owe to F. Ehrlich 52 theinteresting observation that fuse1 oil in alcoholic fermentation isderived from leucine. The leucine is split up by the enzymes, andthe nitrogen-containing groups are used for the formation of pro-teins in the yeast cells. Ordinary leucine yields inactive amylalcohol ; isoleucine gives Z-amyl alcohol.Munures and Munuring.As regards fertilisers, the year has nothing new to show; bothfield and pot experiments continue to be made with the two newproducts containing nitrogen derived from the atmosphere, crudecalcium nitrate and calcium cyanamide,53 and agree with previoustrials to show that the nitrogen of both substances is in a highlyavailable condition.But neither product is yet on the marketon any large scale, although the small factory a t Notodden iscontinually turning out calcium nitrate, and the Italian CyanamideCo. at Piano d’Orta are rapidly increasing their output. It isunderstood that very large works are being erected for bothprocesses, so that next season may see these fertilisers on theordinary market.Meantime, the two substances with which the new fertilisers willmainly enter into competition, ammonium sulphate and sodiumnitrate, continue to receive considerable attention ; there has beenquite a revival of investigations into the relative value and actionson different soils of these two old-standing manures,54 although itcannot be said that any new point of view has been disclosed.Turning from the most recent to the oldest of fertilisers, farm-yard manure, Schneidewind,bS at Lauchstadt, has been continuingthe very interesting series of researches begun by Maercker on theAbstr., 1907, ii, 293.Ibitl., 383.53 Ibid., 48, 295, 573, 646, 807.5J H. Siicbting, ibid., 646 ; Schneidewind, Lniwlru. Jahr., 1907, 36, 598 ;O9 Zaitdw. Jahr., 1906, 36, 569.Kretschmer, &c., Abstr., 1907, ii, 809.T 276 ANNUAL REPORTS ON THE PlLOGRESS OF CHEMIBTRY.losses of nitrogen that are experienced in making dung and thebest methods of conservation that can be adopted in practice.These investigations have the great advantage of being madeon a large scale and under working conditions, and are not opento the objections which attach to most of the laboratory experimentsthat have been reported on materials for conserving dung. Schneide-wind pronounces against gypsum and other materials of like nature ;not only are uneconomical quantities necessary t o be effective insaving nitrogen, but the calcium sulphate becomes reduced tosulphide, which afterwards acts injuriously in the soil. Instead,he confirmed his former observation that the greatest saving ofnitrogen is effected if the base of each new dung-heap is madeof a layer from an old fernienting heap Schneidewind has hardlyarrived a t an explanation, but he thinks the difference may bebrought about by the carbon dioxide evolved from the initial layer ;of the experimental fact he has no longer any doubt.The losses of nitrogen in making farmyard manure have alsobeen studied by T.B. Wood 66 in the course of a feeding experiment,in which four heifers received known weights of food, which wasanalysed from time to time. The dung was not disturbed, but wasanalysed by cutting out sections a t the end of the feeding period,and again six months later. About 15 per cent. of the nitrogenin the food and litter was lost in making the dung, and on storagethe loss increased to 28 per cent.for poor dung made from rootsand hay only, and to 40 per cent. for the richer dung obtained byfeeding also with cotton cake. Since the digestible nitrogen in suchrich foods is excreted as urea, which readily ferments and under-goes loss, even under good management, it is not always possibleto recover in the manure the half of the nitrogen contained inpurchased foods, which is the basis now usually adopted for com-pensation to the outgoing tenant for the fertility he leaves behindon the farm through the feeding-stuffs he has bought and con-sumed during the last year of his tenancy.Chemistry of Animal Nutrition.A paper which is likely to have a considerable bearing on thetheory of animal nutrition, since it throws light on the fact wellknown to practical graziers that the proteins of different foods havenot the same values for putting on flesh, has been published byMiss Willcock and F.G. Hopkins.57 They showed that when zeinis the only nitrogenous food given to young mice, they soon die,but when tryptophan, which is absent from zein, is added, thesurvival of the animals is greatly prolonged, indicating that the56 J. Agric. Sci., 1907, 2, 207. 57 Abstr., 1907, ii, 109AGRICULTURAL CHEMISTRY AND VEGETABLE PHY SIOT,OGY. 27’7tryptophan group is necessary in building up the proteins specificto mice, and that i t cannot be replaced by similar amino-acidslike tyrosine.The view, now generally accepted, that in digestion the proteinsare broken down very thoroughly into simple amino-acids andkindred bodies, which are put through a building-up process inthe intestinal wall68 before they reach the blood, has continuedto receive much discussion.It is well illustrated in an investigationof Abderhalden and his colleagues,59 who found that feeding adog on gliadin (a protein very rich in glutamic acid) did notincrease to any marked degree the amount of glutamic acid in theblood proteins. Bound up with this subject is the question of theutilisation by animals of the non-protein nitrogenous materials infeeding-stuffs. 0. Kellner 6o maintained that they can, to a certainextent, replace proteins in the diet, because they become built upinto proteins by bacteria in the intestine of herbivorous animals;M. Muller 61 finds that soluble non-proteins from hay can be utilisedin the formation of flesh of a dog, whilst I(. Friedlander 62 found thatthe non-proteins of molasses fed in conjunction with food deficientin nitrogen were unable to prevent loss of nitrogen in the animal,although most of the nitrogenous compounds in the molasses couldbe converted by bacteria into proteins.The parallel question of how far animal fat in the body or inthe milk is reconstructed from the fat in the food is discussed ina paper by von Knierim and Bus~hrnann.~3 Feeding milch cowswith various oil-cakes, they found that both the milk yield and thecomposition of the butter fat, as measured by its physical properties,were affected by the feeding in a way which could only be explainedby assuming that some of the fat of the food had passed into themilk unchanged. How far the fat had been broken down in digea-tion and then built up again was not discovered.A nutytical.The determination of phosphoric acid continues to attract a gooddeal of attention; in most countries, the accepted method is toprecipitate as phosphomolybdate, which is dissolved in ammonia,the phosphoric acid being reprecipitated with magnesia mixture.Since it is a lengthy and comparatively expensive process, manyalternatives have been suggested, and two long and critical papershave appeared in 1907 by Mach and Wagner, Kunze, and Simmer-IIs Abstr., 1907, ii, 893.6o Ibid., 491, 794.59 ]hid., 487.%d., 645.63 Lrcndw. Jahr., 1907, 36, 185. Ibid., 895.84 Abstr,, 1907, ii, 395278 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.macher,65 showing that equally accurate results can be obtainedby direct precipitation with magnesia mixture in the presence ofcitric acid, if the silica be first removed. A critical paper on theestimation of potash as perchlorate, as applied to agriculturalanalyses, has been published by Schenke and Kriiger,66 who showthat sulphuric, phosphoric, and hydrochloric acids must first beremoved.A. D. HALL.65 Abstr., 1907, ii, 577. 68 B i d . , 910

ISSN:0365-6217    

DOI:10.1039/AR9070400261

出版商:RSC    

年代:1907

数据来源: RSC

摘要:

MINERALOGICAL CHEMISTRY.PROGRESS in this branch of our science during the past year hasresulted rather from steadily pushing on along old lines of inquirythan from breaking new ground, and we may at once proceed torecord the advances made under the headings employed in the previousvolumes of this Report.General and Physical Chemistry of Minerats.has now attainedits jubilee with the appearance of the fiftieth part of the Researcheson the Formation of Oceanic Salt Deposits.” This paper describesunsuccessful attempts to prepare franklandite, Nrt2CaB,0,,,7~H,0, andthe conclusion is drawn that this mineral is probably an impureboronatrocalcite, NaCaB50,,8H,0. Experiments in which boronatro-calcite and borax were heated, showed that at 60’ the latter wastransformed into Na,B,01,5H20, whilst a t 63’ the former lost water,giving NaCaB,0,,4H20.The upper temperature limit of theexistence of boronatrocalcite is therefore lower than that previouslyrecorded, and the formation of colemanite from boronatrocalcite at about65’ according t o the equation 2NaCaB,0,,8H20 = Na2B,0,,5H20 +Ca2B,0,,,5H20 + 6H20 implies superheating of the latter, In the pre-sence of sodium chloride, borax, potassium chloride, and glaserite, boro-natrocalcite decomposes at 51’. van% Hoff has also been unsucessfulin preparing borocalcite, Ca0,2B20,,4H20, artificially, and specimenspreserved in various collections proved on examination to be boronatro-calcite, pandermite, &c. The deposit formed on heating at 40’ a solutionof lime and boric acid had approximately the composition of borocalcite,but was not homogeneous.The same solution heated to 83’ depositedcolemanite, and this appears to be the most convenient method ofsynthesising the mineral. As these experiments have completed theinvestigation of the natural calcium borates, the results obtained havebeen embodied in a diagram. Turning now to the magnesium com-pounds, it was found that ascharite has the formula 2Mg0,B2O,,H,O.Abstr., 1907, ii, 363, 702.Salt Deposits.-The great work of van’t Hof280 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.A consideration of the mode of occurrence of this mineral suggested thatit could be probably prepared from pinnoite, MgO,B,U3,3H,O, and onheating this substance for eight days at 150’ with a saturated solutionof sodium chloride a deposit was obtained of which the cornposition andproperties were the same as those of ascharite.These borates are hardto prepare, aud it has been noticed that the difficulty of synthesisingthe minerals of the salt deposits increases as we pass from the chloridesto the sulphates and on to the borates, whilst, as regards salts of thesame acid, those of the alkaline earths are harder to obtain than those ofthe alkalis. This phenomenon may be given a quantitative expression,and the various compounds may be arranged in order of their “memvalence,” when it is found that salts for which the numerical value ofthe mean valence is low are easier to prepare than those for which it ishigh.The number to which the term mean valence is applied is aquotient obtained from the formula of the compound as follows; thenumerator is formed by adding certain values assigned to each of theconstituents of the compound, and the denominator by adding certainother values assigned to the same constituents. Thus in the numerator,Na, K, and C1= 1, Ca, Mg, and SO, = 2, B,O, = 6, and H,O = 4. I n thedenominator, Na, I(, C1, Ca, Mg, and SO,= I, B,O,=2, and H,O=3.As an example, we may calculate the “mean valence ’’ for glauberite,CaNa,( SO,), : we have 2 + 2 + 4 + 1 + 2 + 2 = 1.6. Again for ascharite,2MgO,B,U,,H,O, we have 4 + 6 + 4s 2 + 2 + 3 = 2, whilst forGlauber’s salt, Na,SO,,lOH,O, the value is 1.33. The lownumber obtained in the last case is in harmony with the easewith which i t can be prepared, whilst the high value calculated forascharite indicates that it can only be synthesised with difficulty.I n this connexion, attention may be called to a new method ofexpressing van’t Hoff’s results developed by Janecke 2 in several receutpapers.Silicate Fusions.-Reference was made last year to the importantpaper in which J.EL L. Vogt expounded his views on the nature ofsilicate fusions. The continuation * then promised has since appeared,and contains an exhaustive discussion of the phenomena of crystallisa-tion in the case of granitic eruptive magmas. The composition ofthe binary eutectics, quartz-orthoclase and quartz-albite, and of theternary eutectic, quartz-orthoclase-a1 bite (or plagioclase), are dealt within detail, Incidentally it is pointed out that pressure appears to havebut little influence on the composition of the quartz-felspar eutectic.The conclusion is arrived a t that the phenomena of crystallisation inthe case of the acid eruptive rocks can be satisfactorily accounted foron a physico-chemical basis.Abstr., 1906, ii, 833 ; 1907, ii, 278, 480, 702.Ann. &?PO?$, 1906, 301.l‘sch. Mi%. Mitt., 1907, 25, 361MlNERALOGICAL CHEMISTRY. 281The order of separation and mutual relations of binary and ternarymix-turesof diopside, anorthite, nepheline, orthoclase, and magnetite have beenstudied by R. Freis.5 Silicates of definite composition,prepared artificially,werefused together and the melting points of the glasses and of thecrystallised products were determined.The methods of experimentingwere similar to those employed by M. Vu6nik and H. H. Reiter.6 Theorder of separation was found to follow Rosenbusch’s rule, and theconclusion was arrived at that dissociation takes place in these silicatefusions and that the laws which hold for dilute solutions are notapplicable.has examined theelectric conductivity of silicates between 500’ and 1400O. Above 500°,a11 silicates conduct a little, and as the temperature rises the con-ductivity increases. The melting point is a more or less well-definedtransition point i n the temperature-conductivity curve, especially inthe case of those silicates which have a sharp melting point. In thefused stat.e, the temperature-coefficient is inconsiderable, Silicateswhich crystallise on solidification show a not#able change of con-ductivity at the solidifying point, whilst those which give glasses showno such marked change.A t sufficiently high temperatmes, silicatesconduct much like aqueous solutions. Orthoclase and augite werefound to conduct better than plagioclase felspars and hornblende.Law of Roserh.mA. -The law formulated by Rosenbusch, that inthe eruptive rocks the sum of the molecular numbers approaches 155,has been the subject of consideration by E. Sommerfeldt,* whoexpresses it as follows : for any two eruptive rocks A and B, the sumof the individual oxides is such, that equal numbers of gram-moleculesof the oxides exist in A and in 13. This approximately constantnumber is termed by Sommerfeldt the ‘‘ topic ” number, and is obtainedby adding the numbers got on dividing the percentage of the severaloxides by their molecular weights.In the case of an individualmineral, the result may be reached more readily by dividing thecoefficients of the oxides composing it by the molecular weight of themineral and adding the results. To explain the law enunciated byRosenbusch, Sommerfeldt assumes that the minerals which replace oneanother during alterations in the concentration of the magma of eruptiverockd possess similar (“ simultan ”) composition and approximately equalmolecular weights; two silicates being said to be similar iftheir formulae can be so written that in the acid radicle of the first thesilicon offers as many valencies to the oxygen as in the acid radicle ofthe second, whilst the basic radicles agree in the sum of their valencies.Two salts of the same silicic acid are always similar, butElectric Conductivity o j XiZicates.-C.DoelterAbstr., 1907, ii, 183.Anzeiger K, Akccd. W ~ N . Wien., 1907, 289.Ann. Report, 1906, 301.Centr. Min., 1907, 2282 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.similar salts need not come from like acids; thus orthoclasecomes from H,Si,O, and anorthite from H,Si,O,, but H,Si,O, may beregarded as H4Si,Si20s. Anorthite is written by Sommerfeldt,A1(0/2),CaOA1(0/2),Si204, and orthoclase, K(O/2)Al(O/2),Si02Si204 ; inboth cases, the sum of the coefficients of the oxides is 4, and, since themolecular weights are nearly equal, the topic numbers are also nearlyequal.Applying these principles to other rock-forming minerals, thegram-molecule of nepheline is taken to be represented by ( A1NaSi0,)2.Leucite is coneidered as made up of orthoclase and nepheline, 1 gram-molecule of the former uniting with & gram-molecule of the latter toform 15 gram-molecules of leucite. Hence for these two minerals thetopic numbers are the same as in the case of the felspars. Similarconsiderations may be app!ied to the pyroxenes, amphiboles, andmicas, and for these minerals the topic numbers calculated byRosenbusch’s method give results ranging from 143 to 182 in thecase of the pyroxenes (22 analyses, the average value being 166), from143 to 177 in the case of the amphiboles (9 analyses, average value166), and from 165 to 169 in the case of the micas.Art$ciat Formation of Minerals.Interesting results have been obtained in attempts to synthesise thenatural sulphates of iron and t o crystallise sulphates of the alkalineearths.has found that BaSO,, SrSO,, PbSO,and CaSO, can be obtained well crystallised in forms like thoseobserved in nature by evaporating solutions of these sulphates in con-centrated sulphuric acid.On evaporating solutions containingmixtures of any two of the first three sulphates, mixed crystals wereobtained, but attempts to form mixed crystals containing CaSO, and oneof the other sulphates were unsuccessful. Crystals of BaSO,, of SrSO,,and of CaSO, prepared in this way have also been studied by Sommer-feldt,10 who has made the interesting observation that calcium sulphategives crystals exhibiting faces which cannot be brought into harmonywith the axial ratios of anhydrite, although they are comparable withprominent forms found on barytes.Calcium sulphate appears thereforeto be dimorphous, crystallising as anhydrite, and also in this newlabile form, for which the name metahydrite is proposed. A varietyof calcium sulphate found at Santorin possibly represents a naturaloccurrenceof thisvariety. It is worthy of note that the density, cleavages,and optical characters of metanhydrite are the same as those ofanhydrite, the two substances being dimorphous only as regardsexternal form.Barytes Group.-P.Gaubert9 Comnpt. rend., 1907, I*, 877. lo Abstr., 1907, ii, 703MINERALOGICAL CHEMISTRY. 283Copuimbite.-R. Scharizer 11 has prepared coquimbite, Fe,(SO,),,SH,O,by dissolving ferric hydroxide in excess of sulphuric acid. On evapora-tion and after standing for a long time in the air,a mixture of coquimbitewithacidferricsulphate is obtained, from which, by washing with alcohol,the former can be isolated in hexagonal plates, optically uniaxial andpositive. The substance thus prepared agrees closely in compositionand properties with the natural mineral. When dehydrated byheating in a test-tube, a thermometer being placed in the powder, thetemperature remains stationary for a time at 100' and again at about124q 6 molecules of water being lost up to 100' and 7 at thehigher temperature.A neutral solution of coquimbite deposits amixture of copiapite, Fe4S,0,,,18(or 16)H,O, with the acid ferricsulphate, Fe2(OH),(SO,H),,6H,O. Owing to this behaviour, the formulaSO4[Fe(OH)SO,H],,7H,O is proposed for coquimbite. Scharizer hasalso studied the behaviour of roemerite when exposed to moist air,and finds that it decomposes into a mixture of ferrous and ferricsulphates, the latter giving copiapite and acid sulphate.HBmatite.-Fine crystals of hamatite have been noted by C. E.Monroe12 in the interior of the iron pipes of the heater in anapparatus for producing chlorine by Deacon's process. The crystalshave been formed by the action of the hydrochloric acid on the iron,giving iron chloride, and the subsequent conversion of this into oxideby air passed through the pipes.The size of the crystals varies withthe diameter of the pipe in which they were formed. The largest,3 cm. across, were found in a 20-inch pipe.New Minerals.Benitoite.-This exceedingly interesting mineral occurs in colourlessto blue, transparent, rhombohedra1 crystals of trigonal-pyramidal habit(combinations of-trigonal prisms and pyramids with the basal plane),associated with a soda zeolite, in veins in a basic igneous rock orhighly altered schist near the head waters of the San Benito River inSan Benito Co., California. G. D. Louderback13 states that thehardness, whilst greater than that of orthoclase and labradorite, is lessthan that of chrysolite and quartz.The indices of refraction forsodium light are 1.77 (ord.) and 1.80 (extr.). The pleochroism of themineral is very strong (O colourless, E blue), and taken in conjunctionwith its other physical characters and beautiful colour renders itsuitable for use as a gem stone. It is very slowly attacked by moltenpotassium hydrogen sulphate, and is practically insoluble in hydro-chloric acid. It is, however, readily decomposed by hydrofluoric acid.l1 Abstr., 1907, ii, 482. l2 Amer. J. Sci., 1907, [iv], 24, 455.l3 Abstr., 1907, ii, 705284 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.The formula BaTiSi,09 has been deduced from the mean of two con-cordant analyses by W. C. Blasdale :SiO,. TiO,. BaO. Total. sp. gr.BZccnd,fobrdite is a monoclinic pyroxene described by L.L. Ferm0r.1~ Itexhibits strong pleochroism (rose-pin k to sky- blue), and contains somesodium, manganese, and iron.Blomsti*andine.-This name (not to be confused with blomstrandite)has been assigned by Brogger l5 to a mineral found in fine black, ortho-rhombic crystals at Hitter0 (analysis I), and also in the neighbourhoodof Arendal (analysis 11) and elsewhere. The analyses made byBlomstrand show that it is a titano-columbate of yttrium earths ;aeschynite, to which it is closely related crystallographically, being thecorresponding cerium salt. Chemically, it is very similar to polycrase,and it is possible that the two minerals are related to one another inmuch the same way as pyroxene and amphibole :43 68 20.09 36'33 100'10 3.64-3'65Cb,O,.Ta205. TiO,. Sn0,. SiO,. ZrO,. UO,. Tho,. (Y,Er),O,. (Ce,La, Di),03'I. 17.99 0.89 32.91 0.12 0.38 trace 4-01 7.69 28.76 1 *9711. 23-35 1-15 27.39 0.18 0.40 1'33 5-35 4.28 25-62 2'48FeO. MnO. CaO. ZnO. PbO. MgO. N*+O. K20. H20. Total. Sp. gr.I. 1-48 0.27 1.02 - 0.06 0.04 0'22 0'19 1.88 99.88 4.93-4'8211. 1-43 0.30 1.80 0.09 0.84 0.15 0.90 0.18 2.56 99-78 4'91Cadapatite.-See Podolite (page 287).Carlosite.-A black or brownish-black, prismatic mineral, apparentlymonoclinic, occurs associated with benitoite. As its characters do notappear to agree with those of any known species, the name carlositehas been proposed for it by Louderback.16 Its chemical composition isas yet undetermined.Davidite.-D. Mawson l7 has described the occurrence of heavy, blackminerals in pegmatitic veins near Olary, S.Australia. One of these,for which the name davidite has been suggested, is found in scatteredgrains and cuboid crystals remarkable for their very brilliant lustreand glassy fracture. A qualitativeexamination by E. H. Rennie and W. T. Cooke has shown that it con-tains more than 50 per cent. of titanium oxide, a large quantity of iron,and notable amounts of rare earths, uranium, vanadium, and chromium.Small quantities of radioactive carnotite and of a mineral whichappears to be roscoelite have been found in the same veins.Georgiccdesite.-This new mineral, described by A. Lacroixl* and A. B.de Schulten, is found lining cavities in a vitreous scoria surroundingfragments of charcoal and wood at the ancient mines of hurion.ItThe specific gravity is about 4.l4 Abstr., 1907, ii, 701. l 5 Ibid., 884. l6 Ibid., 705.Trans. Roy. S'oc. S. AustraZia, 1906, 30, 188. Abstr., 1907, ii, 971MINERALOGICAL CHEMISTRY. 285is associated with laurionite, fiedlerite, and matlockite. The crystalsare orthorhombic, but- resemble hexagonal prisms. Tile analyt,icalresults agree well with the formula Pb,( AsO4),,3PbC1, :As,O,. PbO. PI,. el. Total. Sp. gr.12.49 38'86 36'38 12.47 100.20 7.1HoZZandite.-In the course of a, comprehensive account of the Indianmanganese-ore deposits,lg Fermor has described a new mineral found atKhjlidongri, JhAbua State, Central India. It occurs in black, pseudo-tetxagonal crystals, showing perfect prismatic cleavages and shiningmetallic lustre.The formula m( Ba,Mti),MnO, + nFe,(MnO,), has beendeduced from the following analysis by H. J. Winch :Fr,O,. A1,0,. Milo,. MnO. RaO. SO,. Total. Sp. gr.10.56 0.94 65'63 5.12 17.59 trace 99'84 4.95A similar mineral occurs as clearage masses a t Sitaprir, ChhindmriraDistrict, Central Provinces.Irvingite is a new variety of lithia-micit found in the pegmatite veinsnear Wausau, Wisconsin. It is described by S. Weidman *O as occurringin crystals about an inch across, grey to yellow or pinkish-white incolour. The axial angle is apparently rather larger than in the caseof lepidolite and zinnwaldite. In addition to a good basal cleavage,many of the crjstals show a well-marked prismatic parting. Ananalysis of pure material made by V.Lenher gave the following results :H,O H,OSiO,. TiO,. A1,03. Fc,O,. FeO. MgO. CuO. K,O. Na,O. Li,O. F. (110"). (ign.)57'22 0-14 18.38 0.32 0.53 0.09 0'20 9-12 5'14 4'46 4.58 0.42 1.24This mica differs from polylithionite in containing mord alumina andless fluorine, the proportions of the alkalis are also ciifferent. Fromcryophyllite, zinnwaldite, and lepidolite, it is distinguished by its highercontent of silica and soda. The formula may be written as a trisilicate,3Si,~[A1,(F,OM)]"0,R2'C), or, according to F. W, Clarke's theory ofthe mica group, as R,'AIX(F,OH), where X represents Si,O, and SiO,in the ratio 4 : 1.Murignacite is a variety of pyrochlore found in small, regular, brownoctahedra associated with quartz, alkali-felspar, and acmite inpegmatite near Fausau, Wisconsin.The mineral is very refractorytowards acids, and is only slightly attacked when fused with sodiumcarbonate. It can, however, be decomposed by hydrofluoric acid orby fusion with potassium hydrogen sulphate. An analysis made bymethods fully described, gave Weidman and Lenher 21 the followingresults :l9 Abstr., 1907, ii, 701. Ibid., 630.Ibid., 482286 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.Cb,O,. Ta20,. SiO,. TiO,. Fe,O,. FeO. Ce20,. Y,O,. Tho,.55-22 5'86 3-10 2-88 050 0.02 13'33 5.07 0.20H2O H2OCaO. MgO. Na,O. K,O. above 110". below 110". Total.4-10 0.16 2.52 0.57 5-95 0'45 99'93A1,0,, MnO, SnO,, WO,, Di,O, La203, Er20, occur in traces, butF, ZrO,, BeO, UO,, Li,O could not be detected.The presence in thispyrochlore of silica and titanium oxides apparently as normal con-stituents, together with its high content of cerium oxide, indicatesrelations to the columbate-tantalates, on the one hand, and totitano-silicates, on the other. Fluorine, which occurs in many pyro-chlores, is here doubtless replaced by hydroxyl.Metanhydrite.-See page 282.N'hangeZZite.-This variety of bitumen from Portuguese East Africahas been described by Sir 16. Redwood.22PaZmierite.-In a long and interesting account of the mineralsderived from the fumaroles of the eruption of Vesuvius, in April, 1906,A. Lacroix23 has described a new species which occurs imbedded incrusts of aphthitalite, (K,Na),SO,. On removal of the aphthitalite bytreatment with cold water, minute, micaceous lamellae of hexagonaloutline are left. These lamellae, to which the name palmierite has beengiven, are uniaxial and exhibit strong negative double refraction.Themineral is anhydrous, and its specific gravity is greater than 3.3. Itis decomposed by hot water, leaving a residue of anglesite. Ahanalysis by Pisani gave the following results :It is allied to coorongite.so,. PbO. K90. Na,O. NaCl . Insol.21.80 40.65 9-10 2.60 2-64 22.59Lacroix believes that if allowance is made for the insoluble residue,which consists in the main of hEmatite, and if the sodium chloridepresent is regarded as an impurity, that the above data lead to theformula (Na,K),SO,,PbSO,. The divergence between the calculatedand the observed numbers is, however, so great that this formula canonly be regarded as conjectural. The numbers published by Lacroixare more in harmony with a formula Na2S0,,2K2S04,4PbS04.It isinteresting to notice that a crystalline compound having thesame physical properties can be obtained by fusing l.ead sulphate witha considerable excess of alkaline sulphates.Purahopeite.-A ssociated with tarbu t tite from Broken Hill mines,North- Western Rhodesia, occurs another species of the same chemicalcomposition as hopeite which has been termed parahopeite by1,.J. Spencer.24 The platy crystals somewhat resemble hemimorphite22 Abstr., 1907, ii, 698. 2d Ibid., 628. 2.1 Nature, 1907, 17, 143MINERALOGICAL CHEMISTRY. 287in appearance, but are anorthic.They have one perfect cleavageapproximately perpendicular to the plates through which emergesone of the optic axes.PodoEite.-Minute, hexagonal crystals occur in cavities in thephosphorite nodules from the district of the river Uschitza, Govt.Yodolia, S. Russia. The crystals somewhat resemble apatite, andexhibit similar optical anomalies, but the birefringence is greater ; themean index of refraction is 1.635 and the specific gravity is 3.077. Theanalysis quoted below shows that the composition must be representedas 3Ca,(PO,),,CaCO,, an apatite with CaCO, replacing Ca(F,CI),.W. Tschirwinsky 25 proposes to call this mineral podolite, andP. Tschirwinsky has accordingly withdrawn the name carbapatite,which he had previously suggested for a substance of similar composi-tion :CaO.Fe,O,. p205. co,. Total.51.15 3 '04 39-04 3'90 97'13Priorife.-Brogger 26 has proposed this name for a titano-columbateof yttrium, cerium, &c., found in the tin gravels of Swaziland, SouthAfrica, and analysed by Prior.,7 The mineral occurs in indistinct,orthorhombic crystals, isomorphous with blomstrandine and dimorphouswith euxenite, the four minerals, euxenite-polycrase and priorite-blomstrandine, forming an isodimorphous group.Quisqueite.-This name has been !suggested by F. Hewett 28 for aremarkable compound of sulphur and carbon, resembling asphaltite inappearance, found associated with patronite (see page 302). A sample,analysed by Hillebrand, had the following composition :s (sol.H,O atin CS,). S(comb.). C. H. N. 0 (diff.). 110". Ash. Sp. gr.15.44 31'17 42'81 0'91 0.47 5'39 3'01 0'80 1-75At present, nothing is known as to the chemical structure of thisReyerite.-(See page 288).Rhonite.-In basalts from the Rhon Mountains and from severalother localities, Soellner 29 has observed a brown mineral which was a tfirst believed to be snigmatite. As, however, the composition provedon analysis to be quite different from that of anigmatite, the namerhijnite has been proposed for it. The mineral is triclinic, and appearsto be isomorphous with znigmatits, which it resembles closely in habit,twinning, and cleavage. I n thin sections, it exhibits strong absorp-tion and pleochroism. The formulasubstance.( Ca,Na2,K,jSMg,Fe~Fe,"'A1,(Si,Ti)00302s dbstr.., 1907, ii, 481.Ibid., 884. '27 Bid., 1899, ii, 433.* Tbid., 789. Ibid., 1907, ii, 072288 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.is based on the following analysis by Dittrich :SiO,. TiO,. A1,0,. Fe,O,. FeO. MnO. MgO. CarO. Ntl,O. KzO. Total.24.42 9.46 17-25 11'69 11.39 trace 12.62 12 43 0.67 0'63 100.568pundite.-Fermor 30 has suggested this name for a garnet, intcr-mediate in composition between spessartite and andradite.Striiverite.-This interesting mineral occurs in pegmatite nearCrareggia, N. Piedmont. It is black and opaque, and has beenshown by Zambonini31 to crystallise in the tetragonal system. Inhabit and angles it is very similar to rutile, tapiolite, mossite, andilmenorutile. The analysis of the mineral was undertaken by Prior,who has found that its composition can be represented by the formulaFe0,(Ta,Cb)20,,4Ti0,.Turbuttite is a basic zinc phosphate, Zn,P20s,Zn(OH)2, found byL.J. Spencer32 associated with lead and zinc ores on a bone-brecciafrom the Broken Hill mines, Norbh-Wes ern Rhodesia. The crystals areanorthic, and show a perfect cleavage. The mineral, which is abundant,is readily distinguished from hopeite and parahopeite by its highspecific gravity, 4.15.T'chernichewite. -This name has been given by Duparc and Pearce 33to a variety of amphibole found as small, acicular crystals in aquartzite near Verkne-Tschouwal, in the Northern Urals. It isdefined by its optical characters, and appears to be rich in iron andsodium.Winchite is also a variety of amphibole.It has been described byFermor,34 and is closely allied to tremolite.New Yttrium Columbium Mineral.-Hauser 35 has anaiysed a mineralas yet unnamed, which will be seen from the following figures to beessentially a yttrium columbate :Ign.Cb,O,. TiO,. Y,O,. La(Ce,Di)20B. A1,0,. FezO,. CaO. PbO. SnO,. Tito,. loss.I. 38.52 6.48 36.99 4-01 0*98 2-34 1.93 0'26 trace trace 8.7611. 45.23 41'19 0.80 2-51 1.80 0'19 trace trace 8-40M~cuceous Zeolites.-Cornu 86 proposes to group under this namegyrolite and zeophyllite together with two new minerals, one termedreyerite, and the other as yet unnamed. Ttie group is defined as consist-ing of hydrated calcium silicates with or without fluoriue, crystallisingin the rhombohedra1 sybtem, and exhibiting very similar cleavages andoptical properties.The individual members may be distinguibhedby their specific gravities and indices of re raction as well as by theircomposition, as will be seen from the following table, in which are given--3o Roc. Geol, Xurv. Iudia, 1907, 35, 22.32 Nature, 1907, 77, 143.3J .Zbid., 701. 35 lhid., 704. 36 Ibid., 483.31 AbstT., 1907, ii, 364.33 Absh.., 1907, ii, 484MINERALOGICAL CHEMISTRY. 259partial analyses of gyrolites (I, from Skye ; 11, from Poonah ; 111,from Bohmisch-Leipa), of zeophyllite from Radzein (IV), and ofreyerite from Greenland (V) :SiO,. CaO. A1,0,. MgO. F. H,O. Sp. gr. p(w).It. 52.63 32.23 - - - 12.96 2'342-2.410 1'546III. 52.89 32-35 -- - - 13.06 2-397 1'542IV.38.82 43'44 2.16 0'26 9'48 8 5 6 - -I. 51.99 32'02 - - - 12'80 2.420 1'54-1.55V. 53.31 32.28 3'27 - - 6.73 2.499-2'578 1.564Minwal Analyses.Great activity has been displayed during the past year in themaking of mineral analyses, and much light has been thrown on thecomposition of rare species. The most noteworthy results are thosebrought together by Brogger in his great monograph37 on thecolumbates, tantalates, and titanates from the Norwegian pegmatiteveins, of which the first part was published towards the close of 1906.The posthumous paper of S. L. Penfield on the composition of theamphiboles also deserves especial notice, whilst all who are interested inmineral analysis will welcome the publication by Hillebrand38 of arevised edition of his memoir on the analysis of silicate and carbonaterocks.I n the following pages, reference mill be made to those analyseswhich are important because made on selected material of which thephysical characters have also been carefully determined, or which throwlight on the composition of species the nature of which has hitherto beenimperfectly understood.Amphibole Group.-The views commonly held at the present time asto the composition of this important and perplexing group of mineralsare those due to Tschermak and Rnmmelsberg respectively. Accordingto the former, tremolite, the simplest member of the group, isCnMg,Si,012, and green actinolite is Ca(Mg,Fe),Si,O,,. I n amphibolescontaining sesquioxides, the existence of molecules, ( Ca,Mg)2A1,Si20,2or ( Ca,Mg)2Fe4Si2012, is assumed, and the occurrence of alkalis i ncertain varieties is ascribed to the presence of Na,A1,Si,0,2 or theanalogous potassium compound.The latter regards the amphiboles asmetasilicates, R"Si0, (R = Ca, Mg, Fe, Mn, Na2, K,) plus varyingproportions of A1,0, and Fe,O,. It had long been the intention ofthe late S. L. Penfield to undertake an exhaustive investigation of thegroup, and after his death a manuscript was discovered in his desk inwhich were given analyses of twelve varieties of amphibole. Thismanuscript has now been p ~ b l i s h e d , ~ ~ and will long rank as a contri-bution of the first importance to the chemistry of this group. The37 Abstr., 1907, ii, 854.38 United States Gcol.S~LTV., 1007, Bull., 305.39 Abstr., 1907, ii, 102.REP.-YGL. 111. 290 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.material was selected with the greatest care, and, by fractionating bymeans of a heavy liquid, was obtained in the highest possible state ofpurity. The analyses were carried out by F. C. Stanley under Penfield’sdirection according to the methods described in the publications ofHillebrand and Washington. The most important result has been thedemonstration of the invariable occurrence in these minerals of con-siderable amounts of water (of constitution) together with appreciablequantities of fluorine. The part played by these two constituents,unaccounted for by the theories of Tschermak and Rammelsberg, hasbeen discussed by Penfield with characteristic acumen.The numberof the constituents and the diversity of composition met with in thegroup lead him to suggest that its members possess a complexstructure. Owing to the so-called ‘‘ mass effect ” of such complexstructures, H,O, Na,O, CaO, MgO, A1203, which are not isomorphousin simple compounds, appear to enter the molecule as isomorphousconstituents. A confirmation of this view is to be found in the factthat amphiboles when fused break up into simpler substances ; theyare, moreover, exceedingly difficult to prepare artificially, and apparentlyrequire for their formation high pressure as well as high temperature.Regarding the acid as the factor controlling the similar crystallisationof these substances, Penfield suggests the possible existence of anamphibole ring derived from a metasilicic acid, H,Si408.Thekpecimens analysed fall naturally into three groups. The firstconsists of two tremolites and four actinolites, the former fromRichville, near Gouverneur, New York (I), and from Lee, Massa-chusetts (11), and the latter from Greiner, Tyrol (III), from Russell,St. Lawrence Co., New York (IV), from Kragero, Norway (V), andfrom Pierrepont, St. Lawrence Co., New York (VI). The ratiosobtained are given in the following table, where TiO, is included withSiO,, H;”O3 represents A1,0, and Fe203, and R” in R”O stands for Fe,Mn, Mg, Ca, K,, Na,, and H, :SiO, : R,”O, : R”O+ F,.I. 0.957 : 0.014 : 0.95811. 0.963 : 0.018 : 0.954111. 0.938 : 0.017 : 0.935IV.0-914 : 0.041 : 0.908V. 0.880 : 0.059 : 0.874VI. 0 876 : 0.045 : 0.923It will be noticed that the ratio SiO,:R‘O+F, is almost exactly1 : 1. I n a general way, this result is in harmony with the views ofRammelsberg and of Tschermak. The former, however, makes noprovision for fluorine, and the assumption by the latter that sodium ispresent as Ns,A1,Si40,, is untenable, for were this so the above ratio1 : 1 would not hold. The presence of fluorine, tervalent oxides, andhydroxyl can, however, be accounted for if the existence of bivalenJIINERALOGICAL CHEMISTRY. 291groupings of the type *AlF*O*FAl* and *Al(OH)*O*(OH) Ale, or, asthey may be written, [ R,”’O(F,OH),]”, are admitted playing partssimilar to those which have been shown to be filled by (MgF)‘ and(Mg,OH)‘ and by (AlF)” or (A1,OH)” in a large number of minerals.It is, moreover, interesting to notice that, although the formulae oftremolite and of actinolite bave long been written CaMg,Si,O,, andCa( Mg,Fe),Si,O,, respectively, yet in the specimens analysed thesum Mg + Ee + Mn always falls far short of 75 per cent., the figures, infact, being remarkably constant in the neighbourhood of 65 per cent.The calcium again, taken alone, never quite replaces 25 per cent.ofthe total hydrogen of the metasilicic acid, but, if the small amounts ofsodium and potassium present be added, this total is reached or slightlyexceeded, whilst after deducting hydrogen present as OH in thehypothetical group [R2”’0( F,OH),]” a considerable, but variable, excessof unreplaced hydrogen remains, which in analysis 111 amounts to 9per cent.The second group includes horn blendes from Renfrew, Ontario (VlI),from Edenville, Orange Go., New York (VIII), from Cornwall, OrangeCo., New York (IX), and from Monte Somma (X).These all differmiddy in composition from those of the group just considered, Theyshow high percentages of sesquioxides and considerable amounts ofalkalis, and are characterised by exhibiting an excess of R”O over thatrequired to satisfy the ratio R”O : SiO, = 1 : 1. As the actinolite fromPierrepont shares this peculiarity, i t is perhaps to beregardedasatransi-tion stage between the tremolites and hornblendes. I n order to deriveall these varieties from the same acid, Penfield finds it necessary toassume the existence in them of an additional bivalent group of thetype *Al(ONa)*ORO*(NaO)Al*, where R = Mg,Fe, somewhat similarto that already introduced to account for the presence of fluorine, OH,and sesquioxides in the tremolites.When this is done, the compositionof these hornblendes can be satisfactorily represented with theexception of that from Monte Somma. In this case, the amount ofwater is small, and only a trace of fluorine is present, It thereforeseems necessary to assume the presence of yet another bivalent radicleof the type R”(OAl),O. It is noteworthy that in all these compoundsthe calcium helped out by small quantities of sodium or potassiumreplaces one-quarter of the total number of hydrogen atoms of theacid just as it did in the tremolite group.Oneof these is the well-known black, basaltic hornblende from Bilin, inBohemia (XI), and the other is a light brown mineral from GrenvilleTownship, Quebec (XII).Analysis of the Bilin crystals leads to theratios SiO, : R,O, : RO = 3.00 : 0.95 : 3.03. This result is remarkablefor its close approximation to the garnet ratios 3 : 1 : 3, and alsoTwo of t.he hornblendes examined stand apart from the rest.u 292 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.because, unlike the hornblendes described above, the ratio SiO, : RO isvery nearly 1 -: 1. To interpret this analysis, Penfield assumes thepresence of a group like that introduced to explain the composition oftheMonte Somma hornblende, but in applying it to the case of theBilin crystals he proposes to double it, one R standing for Fe,iMg, andthe other for Na2,Ca.As the amount of fluorine is very small, it is un-necessary to assume the presence of any other radicle. The Grenvillehornblende is remarkable for the large amounts of fluorine andalumina it contains. It is probable that in this case some of thefluorine is united witoh a bivalent metal, magnesium, for example, toform a radicle present in addition to the groups [AI,0F2]" and[Al2O4RNa2Y'. In both varieties, we note once again that ap-proximately one-quarter of the hydrogen of the acid is replaced bycalcium.The composition of individual amphiboles has been studied by severalother workers. A. Lacroix40 gives an analysis (XIII) made byF.Pisani of a hornblende from a block ejected by Vesurius in theeruption of 1906. The crystals appear to be the same as those identifiedby Zambonini with the variety cutoforite. Lacroix thinks, however, thatthey do not belong to this variety, but constitute a new type. Horn-blendes from the hornblende-gneiss of Markirch (XIVu) and from theserpentine of the Rauenthal, Alsace (XlVb), have been analysed by A.Rhein.41 I n conclusion, we may note that the hornblende whichforms the most important constituentl of the ossexite a t MountJohnson, Montreal, which was analysed by N. N. Evans 42 in 1903, haslately been the subject of a careful optical investigation byH. Tert~ch.~3SiOp. TiOz. A1203. FezOy. FeO.1 57'45 - 1.30 0'15 0.2211.57'60 0'14 1.SO 0.00 0.55111. 56% 0.00 1'24 0.78 5.50IV. 54 80 0.10 2.55 2'50 4.75V. 51.55 1'26 4'36 2% 5'4GVI. 52'31 0.2s 2.69 3'00 6'68VII. 43.76 0.78 8'33 6.90 10 47VIII. 41 09 1'46 l l % 2 2.67 14.32IX. 36'56 1'04 12.10 7'41 23.35X. 39.45 0.30 12.99 7'35 10.73XI. 39-95 1'65 17'58 7'25 2.15XII. 45.79 1-20 11.37 0 4 2 0.42XITI. 41.50 2'42 G.60 12'32 5.30XIVU. 51.60 - 5fl4 2 S4 4.67XIVD. 51.75 - 5.20 2'64 4.52M110.0.07trsco0'48trace0'350.700500'250-771.00trace0.39 -MgO. CaO. KzO. Na20. H20. F. Sp. gr.24'85 12.69 0'54 0'67 1'16 0.77 2.99724'12 13'19 0.22 0.48 1.56 0.37 2'98021.19 12.05 0'28 0'19 1'81 0 04 3.04720.30 12'05 0'24 0'52 1.60 0 77 3.09319.48 10.60 0'35 2'15 1.21 0'46 3 13719.27 11'55 0.50 0.75 1'42 0 9 3 3 11112'63 9'84 1.25 3'43 0.65 1 8 2 3'29011.17 11 52 0'9S 2'49 0'61 O%O 3.2851.90 10'59 3'20 1'40 1'30 0 2 7 -11.47 12.01 4 39 1.70 0.76 050 3'28614'15 11-96 1'9s 3-16 0'41 0.30 3.22621.11 12'71 1.69 2.51 0.67 2'76 3'11015 89 11 70 1'55 2'33 0.37 0 45 3'1s23 75 10'2s - - 1 8 4 - 2 9723'50 10 31 - - 1.54 - -Anapaite.-P.Tschirwinskg 44 has pointed out that anapaite may beregarded as a double salt composed of 1 molecule of vivianite,Fe,(P04),,8H20, with 2 molecules of ornithite, Ca,(P04),,2H20. HeNouv. Arch. Hus. Nut. Hist., 1907, [iv], 9, 90.41 Mitt. Geol. Landesanstalt E'lsass-Lolhl.iikgei~, 1907, 6. 132.42 Anze.r.. J. Xci., 1903, [iv], 15, 391.43 Thclt. 41ha. X i l l . , 1907, 25, 457. -4bAr., 1907, ii, 364MlNERALOGICAL CHEMISTRY. 293has also described several other minerals which occur in the Kerch andTaman peninsulas, South Russia, including one which may be new andto which the formula 100[Fe,O,,P,O,,a~H~O] + 18[ Fe(OH),,3H20] isassigned.Anazcxik-This name was given by Breithaupt to a product of theweathering of nugite from Berg Hradischt, near Bilin.Theso augitepseudomorphs have lately been reexamined by W. P. Smirnoff ,45 whohas isolated the crystalline, biref ringent anauxite from the cimolitewith which it is mixed, and has analysed both substances. The resultsfor anauxite, agree closely with those obtained for a similar mineralfrom Tschakwa, Caucasus, and lead to the formula H4A1,Si50,,,2H2O.The cimolite appears to be a product of the further change of anauxite.The formula H,Al,Si,O,,,H,O is deduced from the analytical resultswhich agree well with those already obtained by R.Scharizer for thesame substance.Apatite.-The paragenesis, crystallography, optical characters, andchemical composition of the somewhat similar apatites from Epprecht-stein, in Bavaria, and from Luxullian, i n Cornwall, have been very care-fully studied by K. Walter 4G with the special object of throwing lighton the relations which exist between the indices of refraction of themineral and i t s colour and composition. Under I is given the mean oftwo analyses of the Epprechtstein mineral. The rest of the analyseswere of material from Luxullian; under I1 being given the results forblue crystsls, under 111 the mean of two determinations made on yellowportions of blue crystals,and under IV the composition of yellow crystalswhich were blue in parts :Insol.P,O,. FeO. A1,0,. MnO. CaO. B4g0. Na,O. K,O. F. C1. H,O.I. 0-29 41.18 0.45 0-22 0.79 53’63 0‘16 0.95 1.03 2.41 0’04 0.3711. 0.27 41’16 0.21 0.19 0-39 54-03 0.15 1.11 1.07 2.60 0.07 0.35111. 0.30 40’78 0’27 0-15 1’74 52-40 0.27 1’09 1.05 2’63 0’10 0.861V. 0’34 40.58 0.33 0.20 4’10 50.53 0‘43 0.96 0 92 2-53 0-13 0.40From the above table, i t will be seen that both specimens are fluor-apatites. The Epprechtstein variety, whilst in other respects similar toapatite from Minot, in Maine, is remarkable for its content in alkali.The interesting point about the Luxu1lia.n apatite is its variation incomposition with colour, the yellow crystals containing more manganeseand less calcium than the blue.In other respects, it resembles theEpprechtstein mineral, and, like it, contains more sodium and potassiumthan is usually met with. As the result of numerous measurements,Walter finds the mean axial ratio a : c = 1 : 0.73381 for the Epprecht-stein crystals, and 1 : 0.73357 for those from Luxullian. For the opticaldeterminations, nine prisms were used (four Epprechtstein and fiveLuxullian). It was found that, although the indices of refraction45 ~!6sh., 1907, ii, 630. 46 Ihid., 481294 ANNUAL REPORTS ON THE PROGRESS OF CHEMISTRY.vary considerably in different prisms from the same locality, thebirefringence remains nearly the same. I n both cases, the indices ofrefraction (in their lowest values) and the birefringence were less thanthose hitherto observed for apatite. The variations observed inthe index do not seem to be connected with the colour of the crystals,but appear to depend rather on the composition, varying with the per-oentage of manganese present, as shown by the following determina-tions made on the material of which the composition is given above :I.11. 111. IV.w . ~ a ... ..... ... 1.6338 1.6337 1'6375 1 $426E.Na . . . . . , . . . . , . 1 -6323 1'6322 1<6359 1'6409BuddeZeyite.-The discovery of three crystals of this mineral in gemgravel from Balangoda, Ceylon, has afforded G. F. H. Smith47 anopportunity for a fresh study of the crystallography of this interestingsubstance.One crystal was analysed by G. S. Blake and proved to bsnearly pure zirconia.ChZoraZZuminite.--Scacchi observed the occurrence of aluminiumchloride at Vesuvius, in 1872, and it has been found in considerableabundance by A. Lacroix48 among the products of the acid fumerolesof the eruption of 1906. By a comparison of the forms and opticalcharacters of the rhombohedra1 crystals with those of A1C13,6H,0prepared artificially, the composition and individuality of the specieshas been established.ChZoromangunokaZite.-A. Lacroix 49 has given further details of thisnew mineral of which a preliminary account was published byJohnston-Lavis last year. Lacroix finds that the crystals are reallyoblique; although they resemble hexagonal prisms terminated byrhombohedra.1% agrees with Johnston-Lavis in thinking that themineral is a double chloride of manganese and potassium, but assertsthat it is an anhydrous compound.CoZumbite.-The crystallography of this mineral has been describedin detail by BrOgger,so and two analyses by C. W. Blomstrand ofspecimens from &merod (I) and Fuglevik (11) have been published.A comparison with columbite from other localities indicates that then-axis increases slightly and the c-axis decreases with an increase inthe amount of tantalum present :Loss onCb,05. Ta,OS. SnO,. SiO,. FeO. MnO. CaO. ignition.I. 72.37 5'26 0.67 - 15.04 5.97 0.58 -11. 71.38 5-87 0'51 0.17 15'86 5'33 0.80 0'12Dimorphite.-J. Krenner 51 has examined small crystals having thecomposition As,S3 prepared by A.Schuller, who made them by meltingAbstr., 1907, ii, 702. 48 Bull. S'oe. f r i q Min,, 1907, 30, 254.49 Ibid, 213. 5O Abstr., 1907, ii, 884.51 Zcitsch. Kryst. Min., 1907, 443, 476MINERALOGICAL CHEMISTRY. 295together realgar with excess of arsenic dust and subsequent sublimationin a vacuum. The crystals so obtained are orthorhombic and tabularin habit ; a prismatic development can be got from solution in carbondisulphide. According to Schuller, this substance also*appears capableof existence in another unstable modification. The chief interest ofthese observations lies in their bearing on the question of the exist-ence of a mineral species termed dimorphite by A. Scacchi, whoobtained it from the Solfatara, near Naples.He described the mineralas existing in two dimorphous forms having axial ratios, which couldnot be barmonised with one another or with those of orpiment. Thelatter is, moreover, readily distinguished from the two former by itsexcellent cleavage. The formula given by Scacchi was As4&. Thespecies was accepted at the time, but doubt was afterwards thrown onits individuality by Kenngott and byE S.Dana, who asserted its probableidentity with orpiment. A comparison of the measurements madeon Schuller's artificial crystals with those given by A. Scacchi forcrystals of his second type have convinced Krenner that dimorphitemust be regarded as a well-defined species.Dnnburite.-The following analysis by Tamura of mell-crystalliseddanburite from Japan has been published by N.Fukuchi : 52SiO,. B,O,. A1,03. Fe,O,. CaO. MgO. K,O. Na,O. H,O.48.87 25-73 0.89 0'12 14-47 7.67 0.77 0.96 0.58BatoZite.-Good crystals from Japan have been found by Tamura tohave the following composition : 53SiO,. B,O,, Al,O,. Fe,O,. CaO. MgO. K,O. Na,O. H,O.38'22 18'24 0.07 0'34 35-33 0.38 trace 0.01 7'86Dolomite.-The important problems presented by the occurrence ofthis mineral have been disciissed at considerable length by Pfaff.54Finding by a comparison OF a number of analyses that magnesiumlimestones containing from 7 to 11 per cent. of MgCO, are very rare,if, indeed, they occur at all, whereas those containing up to 7 Fer cent.of MgCO, and from 11 to 46 per cent. of MgCO, are common, Pfaffproposes to reserve the name dolomite for the latter.After giving aresume of the literature bearing on dolomitisation, and an account ofwhat is known as to the solubility of dolomite and its artificial form-ation in the laboratory, he describes some experiments of his own.These deal with the action of solutions of magnesium sulphate orchloride on calcium carbonate and anhyd rite in the presence of sodiumchloride under pressures ranging from 40 to 200 atmospheres. Withdilute solutions, magnesium limestones result, whilst with concentrated5 J Fcitriigc z . Niirernlyic z'on Jcqmn, 1907, KO. 3, 103.53 Ibid., 104. 54 Abslr., 1907, ii, 480296 ANNUAL REPORTS ON THE PROGIlESS OF CHEMISTRY.solutions normal dolomite is formed. Pfaff suggests that the dolomitesof certain rock-masses may have been formed in a similar way in sea-basins when the salts have become ~oncentrated.~~a We may also notet h a t a number of analyses of dolomite, magnesite, and of various oreshave been published by the authorities of the Austrian GeologicalSurvey.s53gZestonite.-The small, cubic crystals from Terlingua have beennnalysed by Hillebra~~d.~'j The results establish the formula Hg,Cl20,or Hg20,2HgC1, which must be accepted in preference to Hg,CI,O,,t h e formula given by Moses. Hydrochloric and nitric acids decomposethe mineral with separation of calomel, but the hydrochloric acid filtratecontains no mercury, a fact in harmony with the view that thesubstance contains mercurous mercury only. It is at once blackenedby ammonia.Euxenile.-Brogger s7 bas called attention to the close resemblancebetween euxenite and polycrase.The two minerals appear to belongto a series in which the ratio (Cb,Ts),O, :TiO, varies from 1 : 2 t o1 : 5. Brogger proposes t o limit the name euxenite to those membersi n which the ratio is 1 : 3 or less, and to call polycrase those in whichi t is 1 : 4 or more. The ratio 1 : 3 was found in the case of a euxenite,from Alve, analysed by Blomstrand.Euansite.-Specimens of this somewhat rare mineral from Goldburg,Idaho, and from near Columbiania, Alabama, have been examined bySchaller.56 At the first of these localit ies, the massive, amorphousmineral occurs i n seams. I n colour, it is usually brown, but at timescolourless, white, yellow, or dark red.The density varies with thecolour and with the amount of iron present, from about 2.00 (6.6 percent. Fe,O,) t o 1.94 (2.15 per cent. Fe,O,). The index of refractionof the colourless variety is 1.485. Brown material gave the followingresults on analysis :H,O. P205. Fe,O,. AI20,. CaO. MgO. Total. Sp. gr.36-96 19.14 5'49 34.48 4-32 trace 100.39 1-98At the second locality, the mineral is found associated with coal.It is light brown and very brittle.Fergusonite.-Brogger 59 has published a n analysis by Blomstrand offergusonite from Berg, in RBde, Xorway. The crystals exhibittetragonal symmetry, but under the microscope tho material is seen t obe amorphous, and this is probably due t o alteration and hydration.A crystal when heated shows a n incandescent glow and becomesfractured.54a See also E.Phillipi, Jahyb. illin., Fcstbnd, 1907, 397.65 Jahrb. k. Geol. RaicJ~a?~.stnlt, Wien., 1907, 57, 403.56 Abstr., 1907, ii, 788.55 lbid., 790.57 B i d . , 885.59 Ibid., 884MINERAJ,OGICAL CHEMISTRY. 297G'Zcc.serite.-Tn a paper on the formation and transformation ofmixed crystals and double salts in the binary systems of the dirnorphoussulphates of lithium, sodium, potassium, and silver, Nacken 60 hasdiscussed the question of the individual existents of glaserite,Na2S04,3K2S04.01 Prom a study of the freezing-point curves ofmixtures of sodium and potassium sulphates, he concludes t h a tglaserite exists as a hexagonal compound, Na2S0,,3K2S04, at atemperature below the transformation temperatures of mixed crystalscontaining more or less Na2S04 than itself.Glaserite does not mixwith rhombic potassium sulphate, but forms with rhombic sodiumsulphate a series of hexagonal mixed crystals of which the endmember, urcanite, contains fif ty-six moleciilar percentages of sodiumsulphate a t 181'.Han~Zinite.-In 1904, R. H. Solly described some honey-yellow,rhombohedra1 crystals from the Binnenthal, and believed them t orepresent a new species, which he termed bowntanite. The crystals hecollected have since been examined by H. L. Bowrnan,G2 who hasshown that in all probability they are to be referred to i~unzlinite, thebasic strontium aluminium phosphate, A13Sr(OH)7P207, described byS. L. Penfield.Hussakite.-This name was assigned, in 1902, by J.Reitinger to amineral from Dnttas, near Diamantina, Brazil. The mineral closelyresembled xenotime in i t s physical properties, but was found to containa considerable quantity of SO,. This result, which has led to thedescription of hussakite as an independent species in recent text-books,has been sharply criticised by E. Hiissak,63 who supplied the originalmaterial for analysis. After reviewing the evidence and supplementingit by fresh investigation, he concludes that hussakite is merelyxenotime of prismatic habit and that it contains no SO,, the supposediwesence of this radicle being due to a n analytical error. H e there-fore insists that the name hussakite should be abandoned.~~~itchinsonite.-The crystallography and optical characters of thisvery rare thallium mineral found in the Binnenthal by R.11. Sollyhave been carefully studied by G. F. H. Smith,G4 and the material hasbeen examined chemically by Prior. The amount of substance avail-able for analysis was unfortixnately too small to admit of thecomposition being very accurateIy ascertained, but the results of twoanaljses, made on 0.018 gram and on 0.066 gram respectively, suggestthe formula (Tl,Ag,Cu)2S,As2S3 + PbS, As$,.IZnze?torutile occurs in tetrsgonal crystals with the same habit astnpiolite and mossite. Briigger 65 regards it as an isomorphous" Ja?wb. Min., 1907, Bed. -Bd., 24, 1.c;a Abstr., 1907, ii, 703.61 Ann. Report, 1906 319.63 Centr. Afin., 1907, 533.Ahstr., 1907, ii, 699.E5 Ibid. 884298 ANNUAL REPORTS ON THE PROGRESS OF CHEXISTRY.mixture of (TiO)TiO, with FeTiO, and Fe(CbO,),. Crystals fromEvje and Tvedestrand respectively were found by 0. N. Heidenreicht o have the following composition :TiO,. SiO,. Cb,O,. Ta,O,. FeO. MiiO. MgO. CaO.73.78 0.23 13'74 0'43 31.58 trace 0'04 0.2267'68 0.05 20'31 - 11.68 trace trace 0.28Jccmesonite.-An important contribution to our knowledge of thismineral has been made by L. J. Spencer,G6 who has measured a numberof crystals from Clerro de Ubina, province Porco, Potosi, and finds theaxial ratio a : b = 1 : 0,819. The material examined by Spencer hasbeen analysed by G. T. Prior, who obtained the following results : I,for crystals ; 11, for massive jamesonite.S.Sb. Pb. Fe. Cn. Ag. Total. Sp. gr.I. 20.52 34-53 41.18 2-76 0 2 6 0'01 99'26 5.51911. 21.37 34'70 40.08 2-79 0.22 0-13 99'29 5'546These numbers do not lead to any simple formula, They correspondfairly closely with 7(+Pb,$Fe)S,4Sb2S,, which differs a good deal fromthe formula 2PbS,Sb2S3 at present commonly accepted. Spencer,however, points out that the best analyses hitherto published are morein harmony with the complex formula than with the simple one givenin the text-books.Jrmosite.-The vexed question of the existence of a hydrated, normalferric sulphate dimorphous with coquimbite, Fe2(S0,),,9H20,G7 hasbeen the subject of a full discussion by Toborffy.68 After callingattention to the agreement of the crystal-form, cleavage, and opticalcharacters of janosite with those of copiapite, 2Fe,0,,5S03,18H,0,Toborffy points out that in attempting t o establish new species in thisgroup of minerals too much reliance must not be placed on smalldifferences in the proportions of Fe20, and SO, present.These mineralsare decomposition products and are exceedingly difficult to obtain pure,so much so that analyses of coquimbite and of copiapite by differentchemists show wide divergences amongst themselves. I n spite there-fore of the fact that the composition of janosite agrees better with theformula Fe20,,3S0,,9H,0 than with the formula 2Fe,O, ,550 , 18 ,O,Toborffy comes to the conclusion that janosite is really identical withcopiapite. I n this view, he is in agreement with Weinscheak, butdiffers from him and from Linck in holding that copiapite is ortho-rhombic and not oblique.KZei?zite.-The remarkable mercury-ammonium mineral containingchlorine and SO,, of which a preliminary account was given last year,69has been the subject of an exhaustive investigation by Hillebrand70 and66: Abatr., 1907, ii, TOO.68 Abslr., 1907, ii, 629.7O Abstr., 1907, ii, 788.67 llw~.Ikport, 1905, 279 ; 1906, 321.69 Awa. Heport, 1906, 307MINERALOGICAL CHEMISTRY. 299Schaller. Their researches on this mineral and its associat,es, egles-tonite, terlinguaite, and montroydite, will ultimately be described i ndetail in a special Bulletin of the United States Geological Survey ; inthe meantime, a condensed account has been published in the AmericanJournal of Science.The material examined has proved to be identicalwith the unident'ified mercury mineral No. 5 of Prof. Moses, and withthe substance termed kleinite by A. Sachs, and this name is thereforeaccepted for it. The mineral occurs in hexagonal crystals with basalplane and pyramid faces, and has a good basal cleavage. In colour, itvaries from canary-yellow to orange, and possesses the highlyremarkable property of deepening in colour when exposed t o lightbecoming paler again when kept in the dark. A basal section, insteadof being isotropic, exhibits strong double refraction when viewed inpolarised light, and is seen t o have a highly composite structure. Onheating above 130°, the birefringence diminishes and the sectionbecomes uniaxial ; it appears to revert very slowly to the biaxial con-dition on cooling.On heating above 130°, water is evolved, but nosublimate appears until the temperature is raised above 260°, whenmercury and calomel are given off. During the sublimation of thecalomel, a little chlorine appears to be evolved, and at a highertemperature more of this gas appears, followed later by another,apparently sulphur dioxide. Most of the nitrogen escapes as siichduring the sublimation of the calomel, and there is no evidence of theformation of ammonia, There is no certain evidence of the existeiicein the substance of hydrogen other than that present in water, or ofoxygen other than that in water or in the SO, radicle, The averagecomposition of orange-coloured crystals was as follows :Hg.c1. so,. N. II,O. Total.85.86 7-30 3.10 2.57 1-03 99.86The specimens analysed contained quantities of gangue rangingfrom 0.75 to 3 per cent. This was allowed for in calculating theaverage composition. The light-coloured crystals exhibited greatervariations in, and slightly higher mean values for, the percentages ofchlorine and SO, than did the darker ones. The presence of gangueincreases the difficulties of the analysis, and gives rise to uncertainties,especially in the case of the water, the least sa.tisfactorily determinedconstituent. No satisfactory formula can be calculated from theanalytical results, which are neither in harmony with the formulaHg[Cl~S0,],[O(NH2)2]3, suggested by Swhs, nor with the assumptionthat the substance is a compound of the type NHg,X,xH20,where X is C1 and SO,.It seems posjible that the mineral is amixture.Lautite.-An interesting find of this rare mineral has been reporte300 ANNUAL HEPORYS ON THE PROGRESS O F CHEMISTRY.by L. Durr 71 from the mine " Gabe Gottes " in the Rauenthal, nearMarkirch, Alsace. The mineral, which somewhat resembles enargitein appearance, occurs in poor crystals, exhibiting three cleavages,cc very good, b good, c poor. From measurements of the anglesbetween these faces, it is concluded that the mineral is probablyoblique. The following analysis agrees well with the compositionCuAsS :cu. AS. S. Total. sp. gr.This find resolves any doubts as to existence of the species Zautite,originally named by A.Frenzel, in 1880, and later suspected of beinga mixture,Le.ngenbnchite.-Thin f o l i ~ of this mineral, found by R. H, Solly inthe Binnenthal, have been analysed by A. Hutchinson,72 who hasfound the following mean percentages :37 -07 44'53 18'30 99.90 4.53Pb. Ag. Cu. Fe. As. Sb. 5. Total. Sp. gr.57-89 5.64 2-36 0.17 13'46 0.77 19-33 99-62 5.85From these results, i t is concludFd that the mineral is of the type7RS,2As2S3, and that its formula is 6PbS( Ag,Cu),S,2As,S3.Magnetite.-Three specimens of crystallised titaniferous magnetitehave been analysed by H a r r i n g t ~ n . ~ ~ The first, from St. Joseph duLac, Quebec (I), is remarkable for the high percentage of manganesepresent ; the second, from Slagnet Cove, Arkansas (11), is very rich inalumina and magnesia and is intermediate in composition betweenmagnetite and spinel; the third, from Digby, Nova Ecotia (111),corresponds to the formula Fe304, a little of the ferrous iron beingreplaced by magnesium.I n each case, the ratio metals t o oxygen isthe normal one. The titanium may be regarded as present as Ti,O,, oras FeTiO,, isomorphously replacing R,03 :Fe,O,. TiO,. A1,0,. FeO. MnO. MgO. SiO,. Total. Sp. gr.1. 59-71 5-32 0.62 22-70 8-46 3'24 0.16 100.21 4.91311. 59.01 2.40 10.37 16'82 2'10 9.47 - 100.17 4.558111. 70.64 0'24 - 26'13 trace 2.97 0.03 100-01 5.067Jfmzganotnnta Zite.-W. T. Schal ler T4 has described small crystalsfrom Mount Apatite, in Maine. Partial analysis proved the mineral tobe almost pure columbo-tantalate of manganese, only 0.16 per cent.offerrous oxide being present. The density is 7.14, a value whichindicates that tantalic acid largely predominates over columbic acid.il.lirlryy&e.-L. J. Spencer 75 has found t h a t the composition of aspecimen from the Consuelo Lode, Tatasi, Potosi, can be representedas 8AgSb8, + CuSbS,.71 d r i f t . Gcoi. Lnndesnnslnl: Elsass- Lothringen, 1907, 6, 249.54 l b i t l . , 790.5J Abstr., 1907, ii, 277. 73 Ibid., 701.7; ]bid., TOOMINERALOGICAL CHEMISTKY. 301Mica Groi~p.-Tschermak’s theory of the biotites has been discussedby Dalmer,7G who comes to the conclusion t h a t biotites are composedof mixtures of muscovite, R,Al,Si,O,, or phengite, R2AI2Si3Ol0, witholivine, (Mg,Fe),SiO,.The proportions in which the constituents aremixed varies within the limits of 1 muscovite or phengite to 3 olivine,and 3 muscovite or phengite to 1 olivine. R, in the muscovite andphengite formulae represent hydrogen and potassium, but theseelements may be replaced by magnesium and ferrous iron, giving riseto compounds (Mg,Fe) Al,Si,O, and (Mg,Fe)Al,Si,O,,. Potassium isthe predominant alkali metal ; sodium occurs in small quantities only ;lithium, in appreciable quantities, is only found in zinnwaldite andprotolithionite. Silicic acid may be partially replaced by titanic acid,aluminium wholly o r partially by tervalent iron. The olivinemolecules are often partially or wholly hydrated. Calcium andmanganese may occur, and traces of barium can be detected in manyrock-forming biotites.I n a number of biotites, especially inzinnwaldite, a part of the oxygen is replaced by fluorine. As regardsspecial members of the group, we may note that Schaller77 hasdeduced the metasilicate formula( diOJ1,( AlF,),. 27K4. OGLi3.S4Fe”l. 72( AlO),.,,Al”’,. 5;for a zinnwaldite from the York region of Alaska, and that a micawhich occurs associated with lawsonite i n Narin County, California,and which was described as margarite, has been found by Eakle 7s to bemuscovite.Molybdite (Molpbdic Ochre).-The mineral of this name hithei t obelieved to be molybdenum trioxide, Moo,, has been shown by Schaller79t o be in reality a hydrated ferric molybdate, Fe20,,3Mo0,,7~H,O.This formula has been established by analysis of very pure materialfrom Westmoreland, New Hampshire, and confirmed by examinationof four other specimens : one from Telluride, Colorado; another fromRenfrew Ontario; a third probably OF Californiau origin, and afourth from Hortense, Colorado.The New Hampshire mineral has afibrous structure. The fibres give parallel extinction, and exhibit veryst,rong pleochroism and absorption. Crystals of MOO, preparedartificially are quite different in appearance. Results very similar tothese have since been obtained by F. N. Guild,so who has analjsed aspecimen from the Santa Itita Mountain, near the city of Tucson, andhzis arrived a t the formula Fe20,,3MoO3,7H,O. On the other hand,Prince G. Gagarinesl believes that he has found pure molybdic oxideas white or grey pseudamorphs after molybdenite on specimens fromthe Ilmen Mountains.76 Abslr., 1907, ii, 183.F8 Ibicl., 484.79 l b i d , 480, 971. 80 ]bid,, 829. b1 Ibid., 704.77 Ibid., 790302 ANNUAL REPORlS ON THE PROGRESS OF CHEMIS'l'ltY.3rControydite.-A large number of new forms have been determinedon this orthorhombic mineral by Schaller.s2 A direct determinationof oxygen as well as of mercury, made by Hillebrand, confirms theformula HgO.NepheZine.-The formula (K,Na),0,A120,,2Si02 has been given byvon Fecloroff 83 to material from the nepheline beds of the TurjinPeninsula.Olivine.-An analysis by Schaller of an olivine occurring in a veinin the serpentine of Chester and Middlefield, Massachusetts, has beenpublished by C.Pala~he,*~ who also gives reasons for regarding theso-called " hampshirite " of this neighbourhood as serpentine pseudo-morphous after olivine, and not after humite, as suggested byA. L. Parsons.Pntronite.-Last year reference was made to a remarkable find ofvanadium in Peru.85 The mode of occurrence and composition of thisdeposit has recently been described in detail by Hillebrand.86 Thevanadiferous minerals occur in vein formation. Under the hangingwall is a thickuess of about 8 feet of ore, an amorphous material ofcomplex mineral composition, the principal constituent being patronite.Adjoining this is a hard, coke-like substance (86.6 per cent. of carbon),8 inches to 2 feet in thickness, which merges into, and has possiblyoriginated from, a lustrous, black material like asphaltite, for whichthe name quisqueite has been proposed (see p.287). Hydratedoxidation products, rich in vanadium, ferric oxide, and silica, cover theground in the vicinity of the outcrop. A bulk analysis of the oreshowed it to consist in the main of sulphur (51.79 per cent.) and ofvanadium (19.53 per cent.), together with iron, nickel, carbon, silica,and small quantities of other constituents. The ore yields sulphurwhen treated with carbon disulphide, and from the residue hot waterextracts vanadium sulphate. I n order to determine the compositionof the patronite, the vanadium sulphide was removed by warm causticsoda from the material, which had already been extracted by carbondisu phide and water, and the proportions of vanadium and of sulphurin the solution were determined.The results indicate the formulaVS, for the m neral, but i t is possible that the free sulphur extractedby carton disulphide may originally have been present combined withthe vanadium, This view receives support from the fact that theproportion OF free sulphur found increases with the length of time themineral has been exposed to the air, indicating a progressive oxidationof the vanadium sulphide and liberation of sulphur, The iron andnickel present in the ore were found to be associated together asSee also J. Morozewicg,Bull. Acad. Sci. Cmeow, 1907, 958.81 Abstr., 1907, ii, 788.8.1 Amer. J. Sci., 1907, [iv], 24, 491.85 Ann. Report, 1906, 310.ey Ibid., 562.8o rlbstr., 1907, ii, 789blLNERALOGICAL CHEMIS'LXY 303hickeliferous pyrites of the formula (Fe,Ni)S,. The amount of nickelis so much greater than anything hitherto observed in pyrites thatthe specific name bravoite is suggested for this variety.PiEoEite.-G. Friedel 87 has identified specimens of a kind of'' mountain cork " found a t Can Pey, near Arles-sur-Tech, EasternPyrennes, with a substance from Miramont., Haute-Loire, previouslydescribed by him under the name Zassdlite. The water-content andthe composition of the residue after ignition have been determinedfor both varieties, and the formula 5Si0,,Al,0,,Mg0,3~H20 suggested,which differs somewhat from that previously assigned to lassallite.As these minerals resemble closely those described by Heddle aspilolite, i t is proposed to abandon the name lassallite.Powe2Zite.-Two specimens of this mineral, one from Llano Co.,Texas, the other from Nye Co., Nevada, have been analysed bySchaller.ss I n both cases, the mineral is pseudomorphous after molyb-denite, and the results, when impurities are allowed for, agree withthe formula CaMoO,.Purpu!rite.-The discovery of this mineral at two new localities,Hill City, South Dakota, and Branchville, Connecticut, has enabledSchaller 89 to confirm the formula 2( Fe,BIn)PO,,H,O originally pro-posed for the mineral, and to establish the correctness of the view thatthe manganese and iron phosphates are present in isomorphons mix-ture.This is shown by the fact that in the original mineral fromSouth Carolina manganese predominates, in that from South Dakotairon predominates, whilst in the Connecticut mineral iron andmanganese are present in about equal amounts.The density of theSouth Dakota mineral was found to be 3.40, the value previouslygiven, namely, 3.15, is too low, It shows straight extinction and strongpleochroism, rose-red parallel to the cleavage lines and bluish-purpleperpendicular thereto.Pyyiles.-E. H. Kraus and T. D. Scott 90 have analysed and madeexhaustive crystallographic determinations of the beautifullydeveloped crystals of iron pyrites found at I, Central City Mine,Gilpin Co., Colorado ; 11, Franklin Eurnace, New Jersey ; 111, anunknown locality in Colorado. The results are as follows :I.I In. IIb. I IIn. IIIb.Fe .................. 46 *51 45'12 45.28 46-31 46-398 .................. 53'26 53'34 63-26 53-06 53.11............. 1-19 1 *30 c o -Ca ............... - traceResidue ......... 0.59 0.02 0.03 0.54 0.52- -- - -- - _ _ . _ _ . -Total ............ 100.36 99.67 99.87 99.91 100~0267 Bid1. Xoc. f m q Min., 1907, 30, 80.88 Abstr., 19C7, ii, 971. 89 Tbid., 790.Zeitsch. Krgst. Min., 1907, 44, 144304 ANNUAL REPORTS ON THE PltOGIlESS OF CIIEMISTRP.These numbers agree very well with the accepted formula FeS,.Nickel, cobalt, arsenic, antimony, and gold were looked for in I, loutcould not be detected.Pyroxene Group-It has long been known that the members of thisfamily of minerals can be divided according t o their chemical composi-tion into three main groups.The first of these includes substanceswhich may be regarded as members of a series of isomorphous mix-tures, the end terms being diopside, CaMgSi,O,, and heden-bergite respectively, and for them iu consequence MgO + FeO = CaO.The second, Gr augite group, comprises minerals which contain con-siderable quantities of alumina and ferric oxide, and these are regardedas mixtures of the diopside molecule CaMgSi,O, with a moleculeMg(Al,Fe),SiO,. I n the third or aegirine-acmite group, alkalis p1a.yan important part, and NaFeSi,O, is the predominant molecule. I nthe thirty-five years which have elapsed since this classification wasproposed by Tschermak, advances in our knowledge have necessitatedmodifications in our views.Thus Wulfiog has pointed out that mostmembers of the diopside-hedenbergite series contain more MgO andYe0 than can be accounted for by Tschermttk’a theory, and hassuggested that in them a n additional molecule, MgFeSi,O,, is present.Further, a number of pyroxene8 have been discovered which containstill less calcium and more magnesium and iron than any hithertoadmitted to the diopside-hedenbergite series, such, for example, are thepyroxene of the wbin sill analysed by Teall, the pyroxene of adiabase from Eichmond, S. Africa, examined by Cohen, and thepyroxenes which occur in the Juvinas, Shergotty, Nowo-Urei, andBusti meteorites,This class of pyroxenes has lately formed the subject OF anexhaustive review by W. Wahl,91 who has brought together a largenumber of analysis, some thirty in all, and has made a carefulstudy of two new examples.He has also examined the optical char-acters of many of the specimens, of which analyses have been publishedby other workers. H e finds that these pyroxenes occur chiefly indiabases and in meteorites. They crystallise in the monoclinicsystem, contain little calcium, but are rich in magnesium and iron, theformer of these two elements predominating in some specimens, and thelatter in others. Many, especially those found in meteorites, showpolysynthetic twinning parallel to 001. Optically, they are charac-terised by the abnormally low value of the optic axial angle, ZE,which is always smaller than in the case of members of the diopsideseries, and sometimes sinks t o 0’.H e finds, moreover, that the angle2E may vary in different crystals from the same locality, or even indifferent portions of the same crystal. I n this case, continuous vsria-y1 Y’sch. Mi?i. Mitt., 1907, 26, 1MINERBLOGICAL CHEMISTRY. 305tion is frequently met with, the angle increasing from the centre tothe periphery. The extinction angle on 010 is lower than that of thediopside series.Two characteristic examples have been analysed by Wahl.gl" I n thefirst, from Kallsholm, Foglo, Alands Islands (analysis I, below), 2Ereaches a maximum of 3 5 O in the exterior portion of the crystallinegrains, the centres being nearly uniaxial. The double refraction isfairly strong and positive ; the extinction angle on 010 is 444'.Inthe second, which occurs in a coarse-grained diabase near the villageof Schtscheliki, on the S.W. bank of Lake Onega (analysis 11, below),the angle 2E varies from about 41' in the interior to 7 3 O on the out-side ; the extinction is 45'. I n this, as in the majority of specimensexamined, the plane of the optic axes is parallel to the plane oEsymmetry of the crystal :SiOz. TiO2. 8 1 2 0 3 . FePOs. FeO. NO. MnO. MgO. CaO. N t O . KzO. HzO Total.I. 61.30 0 72 2'36 2.22 18'53 0 05 057 16.56 6.96 0'21 0.37 1.00 101'1511. 50'50 0.80 2'49 3.35 15'15 0.04 056 11.37 13'97 05% 0'1'3 0.55 101.0'3The optical characters of a pyroxene from the diabase of Richmond,Cape Colony, are, however, peculiar, inasmuch as when traversed acrossthe field of the polariscope the value of 2E sinks from 314' to 0" andthen increases again to 20p in a plane at right angles, the crystal re-maining positive.That is to say, that, whilst the acute bisectrix main-tains the same direction, the plane of the optic axes changes from aposition parallel to the plane of symmetry to a position at right anglesthereto. I n the first position, the dispersion is p>v, and in the secondp<v. The optic axis plane tends in fact t o approach the position itoccupies in enstatite and hypersthene if these substances are placedwith their prismatic cleavage planes parallel to those of pyroxene.The pyroxene of the Juvinas meteorite exhibits similar behaviour.These observations give the clue t o the explanation suggested byWahl, who points out that the composition and optical properties of thesepyroxenes may be satisfactorily accounted for if we assume that in themwe have a series of mixed crystals formed, on the one hand, by membersof the diopside-hedenbergite (or augite) series and, on the other,by magnesium and iron metasilicates which have the optical propertiesof the rhombic pyroxenes.As the proportion of the latter increases,the percentage of calcium, the value of ZE, and the extinction anglediminish. This substitution may continue until the resulting mineralbecomes uniaxial, or even until the optic axes separate again in a planeat right angles t o the plane of symmetry. Wahl does not, however,think that the series is necessarily a continuous one, and he believes thatprobably a gap occurs, the series belonging t o type IV or, perhaps, t o9ia Compare also an analysis recently published by Dittrich of a pyroxene' fromTasmania. Cent?*.Min., 1907, 705.REP.-VOL. IV. 306 ANNUAL REPORTS OF THE PROGRESS OF CHEMISTRY.type V of Roozeboom’s classification. This explanation involves thecrystallisation of monoclinic substances with rhombic ones. Anyobjection on this score is, however, more apparent than real, for thecleavages and angles are very similar in both classes ol pyroxenes ; in-deed the rhombic members of the family have been sometimes held tobe pseudorhombic and really monoclinic. Wahl therefore proposesthat the name enstatite-augites should be assigned to these minerals.It should, however, be noticed that the magnesium metasilicate pre-pared artificially by Ebelmen has properties very similar to those ofthe pyroxenes of meteorites, and we may perhaps have to look to thissubstance rather than to enstatite or hypersthene for the other com-ponent of the mixed crystals.Wahl puts this view on one side, butthe recent work of Allen, Wright, and Clement lends it probability,and further observations, especially synthetic experiments, are neededreally to settle the question.Analyses of Ibedenbergite of salile and of other members of the pyrox-ene group have also been published by A. Rhein9z and by N.Fu ku~hi.~3Pywhotite.-Four specimens of Sardinian pyrrhotites have beenanalysed by S e ~ a . ~ ~ One of them appears to have the formula Fe8, butthe remainder agree better with Fe,,S,,.RammeZsbergite.-The following composition has been found byL.Durr 95 for spherules with radial structure and silver-white, metalliclustre which occur at the mine ‘* Gabe Gottes,” Markirch, Alsace :As. Fe. Ni. Co. S. Total. Sp. gr.66.84 19-48 11-09 1-72 0.56 99.69 7‘5If the sulphur is assumed to be due to the presence of mispickel asan impurity, these results give the formula Fe,lNi,CoAs,,. This differsso widely from the type RAs, that Durr thinks that the substance ispossibly a mixture. The mineral resembles in composition chloanthite,from St. Andreas berg and so-called chathamite.Rock XaZt.-StZrba 96 has observed that the gases produced whenblue rock-salt is dissolved in water always contain more hydrogen thanthe gases from colourless material.This observation appears t osupport the view that the blue colour is caused by sodium.Samarskite.-Two new analyses have been published by BrOggery97but on optical examination the material mas found to be not quite02 Mitt. Geol, Landesanstalt Elsnss-Lothriiigen, 1907, 6, 132.93 BeitrcZge x. Mineralogie von Japan, 1907, No. 3, 77, 83, 86, 92.94 Abstr., 1907, ii, 361.g5 Mitt. Gcol. Landesanstalt Xl.sass-Lothringe?t, 1907, 6, 230.97 Abstr., 1907, ii, 886.Anzeiger K. Akad. Wiss. Wien., 1907, 71MINERALOGICAL CHEMISTRY. 307homogeneous, and no definite formula can be deduced from thoresults.XcheeZite.-Lovisatog8 has described an occurrence of this mineral fromGenna Gureu, Sardinia.An analysis by C. Rimatori showed that itwas exceedingly pure, the analytical numbers agreeing very closelywith those required for the formula CaWO,. Molybdenum, a constitu-ent of all scheelites previously examined, was absent. The mineral masaccompanied by mey macite (hydrated tungqtic oxide), which was alsosubmitted to analysis.XeZenium-Minute flakes of selenium have been noted by R. Bellini 99on lava of the Vesuvian eruption of 1906. This is interesting becauseit is doubtful whether selenium has ever hitherto been found native.8emseyite.-An analysis by Prior of a specimen of semseyite con-taining silver has been published by L. J. Spencer.1Xmithite.-The composition of this rare mineral, found in theBinnenthal, has been ascertained by Prior to be as follows :Age As.Sb. 8. Total. Sp. gr.43.9 28-9 0.4 26.0 99.2 4-88These numbers agree closely with the formula AgAsS,. The crystal-lographic and optical characters have been determined by a. F. H.Smith.2XtoZpenite.-An amorphous, pink mineral resembling bole occurs inclefts in a basalt quarry near Nordheim, Rhon, and has been examinedby Fersmann.3 On analysis, it proved to be a member of the mont-morillonite group, resembling a mineral from Stolpen in Saxony.of the oblique crystalshave established the existence of a very large number of forms, andcomplete analyses by Hillebrand confirm the accepted formulaHg,ClO, or Hg0,HgCl. The mineral is decomposed by hydrochloricand nitric acids with separation of calomel. The hydrochloric acidfiltrate contains bivalent mercury.Tetruhedrite.-L. Durr 5 gives the following analysis of a crystalfrom Markirch, Alsace, and thinks his results are best expressed bythe formula 4Cu,S,Sb,S, + Cu,S,FeS,ZnS,As,S, :cu.Fe. Zn. As. Sb. s. Total.42.13 3'48 4'40 9 '74 12.44 27.00 99-19~erZi~guccite.-Measurements by SchallerIt is not blackened by ammonia.Titunite.- J. Bruckmoser 6 has studied the acids obtained by Tscher-From the latter, mak's method 7 from harmotome and from titanite.98 Abstr., 1907, ii, 452.Abstr., 1907, ii, 700. B i d . , 699.Ibid., 561. Ibid., 788.Jfitt. Gcol. Lnndesnnstnlt Elsass-Lothringen, 1907, 6, 205.99 Centr. Min., 1907, 611.ti dnzeiger K, Akacl. V i s s . T l ' i e n , 1907, 476.7 A m . Aeport, 1906, 303.x 308 ANNUAL REPORTS OF THE PROGRESS OF CHEMISTRY.the acid, H,Ti,O,, is obtained as well as a silicic acid, H,Si,O,.He con-cludes therefore that the formula of titanite is Si20,Ca,0,Ti,. Harmo-tome gave an acid, H8Si,01,.from Coloradohave been found by G. P. Tschernik to have the following composition :32.69 0.13 55.36 0 -08 20'43Y'opaz.-Perfectly transparent, wine-yellow crystalsSiO,. TiO,. A1,0,. CUO. F.TourmaZine.-The two following analyses have been made : (I), bySchaller on carefully selected material got by breaking up pale pinkcrystals from Elba ; (11), by Serra lo on material from large, blackcrystals found in a pegmatite vein a t Asinma, Sardinia :SiO,. TiO,. P2OP B,O,. AI,O,. Ti,O,. FeO. Milo.1. 37'89 - - 10'28 43.85 0.04 0.11 0'1111.35.43 0.56 trace 9'72 37'29 - 5.65 0.89CaO. MgO. K20. Na,O. Li,O. H,O. F. Total. Sp. gr.I. 0.07 - - 2'43 1.66 3.47 0'10 100'01 3.04-3-0511. 1'10 4'60 0'64 2.27 - 1.50 0.12 99.77 3 '08I n analysis I the ratios SiO, : B,O, : total H = 4 : 0.93 : 20.08 ;numbers in harmony with Penfield's theory.~rechmunnite.-Qualitative tests make it probable that this speciesis a sulphnrsenite of silver, but enough material for a quantitativeanalysis is not yet available. The morphological characters of the small,rhombohedra1 crystals have been fully determined by G. P. H. Smith."T~ch~rr?zigite.-Octahedral crystals with cube faces, found in browncoal a t Nieder Georgenthal, near Briix, have been identified by A. Sachs12with the somewhat rare ammonium alum, tschemzigite.The mineralproved on analysis to be nearly pure, and is optically perfectly isotropic.A specimen of the same mineral from Schellenken, near Dux, Bohemia,was found by Cornu l3 to have a density 1.636 a t 18' ard to beis0 tropic.VaZentinite.-Pure crystals from Bolivia hzve been found by Prior14to possess the accepted formula Sb20,.Yttyocerite.-The formula Ce2F,.2Y,F,,9CaF,,2H20 has been foundby Tschernik l5 for violet-blue crystals from Colorado :Ce,OS. Y,O,. CaO. H,O. F. Al,O,,SiO,. Sp gr.18.19 29'36 27.61 1.96 37.69 trace 4-307Yttrotantalite is isomorphous with samarskite, tantalum predominat-Two analyses ing in the former mineral and columbium in the latter.have lately been published by Bro,ager.l'jAbstr., 1907, ii, 362.lo Ibid., 1908, ii, 116.Bid., 791.l4 Abstr., 1907, ii, 700.l6 Ibid., 887.Ibid., 790.Ibid., 1907, ii, 699.14 Centr.Min., 1907, 467.1s Ibid., 362MINERALOGICAI, CHEMISTRY. 309Zeolite Group.-Analyses of analcite, ckabazite, mesolita, PLatrolite,rrcolecite, stilbite, and thomsonite, from New South Wales, have beenpublished by C. Anderson,17 and K. Jimb6 Is has investigated specimensof analcite, upophyllite, stilbite, and heulandite from Japan. Twomembers of this family have also been caref iilly studied by E. Baschieri,lgnamely, natyolite and the variety of laumontite termed caporcianite bySavi. To a specimen of the former from hfontecatini, Val di Cecina,he assigns the formula Na2A12Si30,,,2H20, whilst he finds that thelatter is CaA1,Si4014,4H20. The acid isolaked from both these mineralsby Tschermak’s method appear t o be orthosilicic acid.Special Reactions of Minerals.In 1904, it was shown by Suida that silicates containing acidhydroxyl groups became strongly coloured when treated with solutionsof basic aniline dyes. Cornu 2o has examined specimens of serpentinemuscovite, lepidolite, and sericite which had been stained by Suidawith methylene-blue or with magenta, and finds that they exhibitpleochroism, the absorption scheme being independent of the dye used.H e concludes that the process of staining is not to be regarded as apurely physical phenomenon, but that chemical change probably takesplace. Gaubert,21 however, has found that minerals which arestained by basic colours also take up acid dyes, whilst chrysotile andpilolite absorb methylene-blue even after they have been heated toredness, and his observations have led him t o the conclusion that theprocess of absorption is a physical one.Cornu22 has continued his experiments on the acid and alkaline re-actions of minerals to which reference was made last year,23 and hastabulated the results obtained f o r silicates, carbonates, phosphates,arsenates, borates, and certain hydroxides.Meteorites.Farrington 24 has made a useful compilation of about 360 publishedanalyses of 248 meteoric irons, and has tabulated them according to thestructure of the irons. The average composition of the irons isapproximately : Fe, 90 ; Ni, 9 ; Co, 0.9, and Cu, 0.02 per cent. Ofindividual meteorites examined during the year, the two following fromNorth Carolina are of interest, both have been described by Merrill25and analysed by Tassin.17 Abstr., 1907, ii, 887. Beitragc z. Afineralogie ron Japan, 1907, No. 3,115.19 Proc. Verb. Soe. Toscana Sci. Nat., March 3, 1907.2o Tsch. Mzn. Mitt., 1907, 25, 453.p2 Tsch. Min. Mitt., 1907, 25, 489.24 Abstr., 1907, ii. 706.a1 Abstr., 1907, ii, 479.‘L5 Ibid., 278, 484.Awn. Report, 1906, 330310 ANNUAL REPORTS OF THE PROGRESS OF CHEMISTRY.Hender8onviZZe.-This meteoric stone was found in 1901, butprobably fell about 1876. It is chondritic in structure, and consists ofenstatite, a monoclinic pyroxene, and olivine with metallic particles.Its mineralogical composition calculated from analyses is : nickel-iron, 2.59 ; troilite, 4.43 ; schreibersite, 0.08 ; chromite, 0-80 ; olivine,40.48, and pyroxenes, 51.62 per cent.Rich Mountain.-This stone was seen to fall in 1903. Fromanalyses of the metallic portion and of the soluble and insolublesilicates, the following mineralogical composition has been calculated :nickel-iron, 7.831 ; troilite, 3.89 ; schreibersite, 0.20; olivine, 46.99 ;insoluble silioates (enstatite, &c.), 40.67 ; magnetite, 0.15, and graphite,0.015 per cent.I n conclusion, attention must be called to the elaborate investigationmade by F. Rinne and H. E. Boeke26 of the meteoric iron namedEl Inca found in 1903 in the Pampa de Tamarugal, Iquique, Peru.A. HUTCHINSON.26 Jnhrb. Min. Festbancl, 1907, 227

ISSN:0365-6217    

DOI:10.1039/AR9070400279

出版商:RSC    

年代:1907

数据来源: RSC