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Proceedings of the Chemical Society, Vol. 13, No. 182 |
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Proceedings of the Chemical Society, London,
Volume 13,
Issue 182,
1897,
Page 141-163
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摘要:
Issued 22/711897. PROCEEDINGS OF THE CHEMICAL SOCIETY. EDIZ',YD BY THE SECRETARIES. No. 182. Session 1896-7. June 17th, 1897. Professor Dewar, F.R.S., President, in the Chair. Mr. Samuel Pollitt was formally admitted a Fellow of the Society. A Certificate was read for the first time in favour of Mr. Oscar Guttmann, 12, Mark Lane, E.C. The following were duly elected Fellows of the Society :-William Ackroyd ; Walter Harry Barlow ; William Malam Brothers ; Gerald Noel Brown ; Ernest Stuart Cameron ; Medwin C. Clutterbuck, B.Sc., Ph.D. ; William Cranfield ;A. Bilderbeck Gomess ; Frederick Roscoe Grundey, 16.S~. ; Edward Halliwell ; Frank William Harbord ; Harold Harman ; B. J. Harrington, Ph.D. ; John Edwin Mackenzie, B.Sc., Ph.D. ; William Robertson Pollock ; Lionel Walter K.Scargill, B.A. ; James Porter Shenton ; William Taverner. Of the following papers, those marked * were read :-*79. (( Molecular refraction of dissolved salts and acids." Part 11. By J. H. Gladstone, D.Sc., F.R S., and W. Hibbert. The present paper is a continuation of a previous communication to the Society two years ago, under the same title (Proc., 1895,11,120). It is especially concerned in replying to the questions, "Has a salt the same molecular refraction whether it be in the crystalline state or in solution 1 " and "How far is any refraction change dependent on the solvent used?" The paper also gives some conclusions to which the data appear to lead. In a table previously published (Trans., 1895, 67, 831), there were many comparisons between the specific refraction of solid salts and their value in solution, but no crystals were examined excepting those which had only one axis, or where the different indices were very near together. By adopting the method of Damien as suggested by Pope, we now add seventeen more cases having two or three indices of refraction.The observations are in accordance with the conclusions previously drawn, 142 the refraction of the salt in solution being in some cases greater, and in other cases smaller, than that of the crystallised body. The change of refraction however rarely, if ever, amounts to 4 per cent. In making experiments on the effect of different solvents, we have examined nine salts and acids, including those published in 1870 (Trans., 1870, 23,101).The first result is to show that the specific refraction of the substances dissolved in water does not generally differ much from the value yielded by solution in other solvents. If, how-ever, we examine those substances which show a great change of refrac- tion when deduced from different strengths of solution in water, the result is very striking. A comparison of hydrochloric acid when dissolved in water and in different alcohols and ethers, is shown in a diagram of curves. Whilst in water the specific refraction of the acid is raised in the first instance from about 0.300 to 0.386, and then gradually rises on dilution to 0.400, the acid dissolved in the different alcohols shows a lower starting point and a more gradual rise, in the following order : methyl, ethyl, amyl, and capryl alcohols ; followed by a very low starting point in the case of ethyl ether, with an actual decrease on dilution, and by scarcely any change at all in the case of amylic ether.In the case of lithium chloride, which gives in water a curve rising on dilution second only to that of hydrochloric acid itself, the solution in alcohol yields a curve very similar in character, Ferric chloride, which is the most striking instance of a great decrease in refraction occurring on dilution with water, shows also a decrease when it is dis-solved in alcohol and acetic ether. Nitric acid, when mixed with water, shows a great change of specific refraction, but when dissolved in nitro- benzene shows little if any.The authors express their growing conviction that neither the salt nor the solvent really changes its specific refraction, but that by their interaction some new product or products result, in quantities deter- mined by the proportionate amount of the two original substances. The action may be one of dissociation or of association, or of some hitherto unrecognised redistribution. It is the changing proportion of this tevtium quid which makes itself apparent by the changing specific refraction of the solution. DISCUSSION. The PRESIDENTsaid that the Society was much indebted to Dr. Gladstone for this last addition to his great work on the refractive indices of chemical substances.He wished it were possible to determine directly the refractive index of fluorine, which seemed, from Dr. Gladstone’s results with fluorine compounds, to possess the smallest refractive power of any of the elements. 143 Professor DUNSTAN asked whether the authors had considered the possible influence of the formation of the alkyl chlorides on the solutions of hydrogen chloride in alcohols. Dr. GLADSTONE,in reply, said they had been unable to detect the formation of any alkyl chloride in the solutions. "80. "On a space formula for benzene." By J. Norman Collie, Ph.D., F.R.S. In this formula six tetrahedra (to represent the six carbon atoms) are arranged symmetrically in space equidistantly from a common centre, and so that they would occupy the six solid angles of an octahedron.They are connected also symmetrically with one another by single link- ings. If the six hydrogen atoms (of benzene) are then arranged sym- metrically on these tetrahedra, it will be found that there dl be three on one side of the figure and three on the other side. Movement in this arrangement might take place in two ways, a move- ment of each tetrahedron about its own centre, and a movement of each tetrahedron about the centre of gravity of the whole mass. In the first case, simultaneous rotational movement of each tetrahedron about its centre would bring the combined hydrogen atoms towards the centre of the mass in two distinct sets ; those on the I, 3, 5 carbon atoms and those on the 2, 4, 6 carbon atoms, and a projection of this configu- ration might be expressed as follows : In the second case, movement about the common centre would alter the relative positions of the tetrahedra with regard to one another, bringing into play the six unsaturated points of attraction on these tetrahedra.The projection of these different phases can be represented by the following formulae : H H H H H H n Y First phase. KekulQ's Centric Iiekul6's Last phase. formula. formula. formula. 144 This space formula is therefore in complete accord with that of Kekuld and the centric formula, and shows how they are mutually convertible the one into the other. It also shows how the supposed double bindings in the Kekuli! formula shift between the carbon atoms, thus rendering two orthochlorobenzenes impossible.But it differs from both, in that it shows how there may be two distinct sets of hydrogen atoms, and that when one set is inside the molecule, the other set is outside the molecule. It can offer an explanation also of the fact that when one set of groups is present in a benzenoid compound, further substitution gives ortho- and para-diderivatives ; whilst, when another set is present, on further substitution meta-diderivatives only are formed. When chlorine acts on nitrobenzene, the chief product is metachloro-nitrobenzene. The nitro-group belongs to the group that favours the production of meta-diderivatives. This nitro-group, being in a sense unsaturated, might possess a certain amount of '' residual affinity " which would be sufficient to attract the entering chlorine molecule, and direct it towards the hydrogen atoms that come to the centre at the same moment that it does itself.___t ------+ H On the other hand, in the case of chlorobenzene,if nitric acid be allowed to react with it, no such additive compound would be produced, and the attraction of the three hydrogen atoms attached to the other three carbon atoms might just be sufficient to determine its reaction with them. c1 CI CI para. ortho. DISCUSSION. Professor TILDENthought the paper a valuable contribution to the theory of the construction of the benzene molecule, though he felt doubt- ful about the validity of the division of the substituents into saturated and unsaturated, since this distinction was, in any case, not a sharp one.Mr. SWORNconsidered that the foimula proposed did not differ materially from the octahedral formula of Victor Meyer and others, nor did the explanation by the law of substitution now suggested differ substantially from one proposed by himself in a paper published in the Philosophicul Maguxine. Dr. KIPPINGsaid he was not satisfied with the conclusion that three hydrogen atoms in benzene occupy different positions to the other three. If this were true then two monosubstitution derivatives become possible. From the readiness with which rings are formed from side groups, it would appear that the meta-position corresponds with the ortho-position.Mr. FRISWELLsaid that the ordinary nitration of toluene gave a mixture of about 65 parts of orthonitrotoluene and 35 of paranitrotoluene, or very nearly 2 to 1. In conjunction with Dr. T. A. Lawson he had endeavoured to alter these proportions. Every possible variation of temperature down to nitration at or near zero or as high as 40°,every variation of nitrating mixture from large proportions of sulphuric acid to the use of nitric acid alone, every variation in the order and rate of mixture, the nitration of toluene in which paranitrotoluene had been previously dissolved, had been tried. Yet no important variation of the proportions of the two products had been produced. Mr. A. G. Green had repeated these experiments, and confirmed them.The space formula now suggested by Dr. Collie afforded an explanation, since there were two orthohydrogen atoms during the rotation postulated inside the ring, and only one para- hydrogen atom in that condition. He had long considered this problem, and he had, in conjunction with Mr. C. Mills, commenced to experiment in order to ascertain whether the results might not be due to the existence of two isomeric toluenes. Professor COLLIE,in reply, pointed out that the space formula for benzene which he had proposed was necessarily similar in many respects to others, notably those of Vaubel and Sachse ; but the point on which he wished to lay especial stress was, that there were two sets of hydro-gen atoms, and that when one set was in4de the molecule the other set wns outside.146 "81. '' On the production of some nitro-and amido- oxypicolines." By A. Lapworth, D.Sc., and J. Norman Collie, Ph.D., F.R.S. When dioxypicoline (Trans., 1891, 59, 617) is warmed with 60 per cent. nitric acid, a nitro-compound is at once produced, C1,H,N02+ HNO, =C,HGN20,+H20. This nitrodioxypicoline possesses all the properties of a nitrophenol, it is light yellow in colour, and forms salts with bases. When it is carefully reduced with tin and hydrochloric acid, an amido-oxypicoline results, but should the temperature rise too high a secondary reaction occurs and a trioxypicoline is formed instead, (1) C,HGNzO, + 3H2 =CGH6NO,(NH,) + 2H20, (2) C,H,NO,NH, + H2O =C6HGN02(OH)+NH,. The molecular constitution of these three compounds may be expressed by the formulse : 7\ A ACH,-E ?*OH CH3-C VOH CH,-E ?OH HC CNO, HC CNH, HC COH \\(-/ \c/ \C/ OH OH OH Nitro-compound.Amido-compound. Trioxypicoline. The amido-compound is remarkable for the series of brilliant colours it produces when treated with various oxidising agents: deep indigo- blue with ammonia and air, orange yellow with nitric acid, a deep moss green with alkaline ferricyanide of potassium, and a brilliant magenta with weak acetic acid and potassium bichromate. These colorations are very similar to those produced when various alkaloids are treated in a similar manner. This amido-oxypicoline forms salts with strong mineral acids but is also capable of liberating carbon dioxide from alkaline carbonates.When its hydrochloride is only partially neutralised with sodium carbonate and the solution is boiled, an excessively insoluble substance separates, which seems to be a compound of the dioxyamidopicoline and the trioxypicoline, 2C,H,N02(NH2)+H20=C,,H,,N,O, +NH, + H,O. This insoluble compound by persistent boiling with strong hydrochloric acid is finally changed into the trioxypicoline and ammonia. The trioxypicoline may be prepared at once from the dioxyamido- picoline hydrochloride, by using the full amount of sodium carbonate necessary to neutralise the hydrochloric acid, and then boiling for half an hour. It then crystallises out in long, needle-shaped crystals. This trioxypicoline resembles pyrogallol in many of its reactions, it is an excessively powerful reducing agent, and in alkaline solution will develop photographs.It will precipitate silver from a solution 147 containing a considerable quantity of free nitric acid, and it also gives with oxidising agents a series of colour tests similar to those of the dioxyamidopicoline. “82. (‘Further experiments on the absorption of moisture by deliques- cent substances.” By H. Wilson Eake, Ph.D. In a preliminary note (Proc., 1896, 12, 33) the author showed that certain deliquescent salts, when exposed to the air, attained a maximum of hydration, and that its maximum corresponded to a definite number of molecules in a large number of cases. In the preliminary experiments no reference was made to the vapour- pressure of water in the air, but in experiments since made, the con- dition of the atmosphere as regards iiioisture has been carefully noted, or an artificially saturated atmosphere has been contrived under known conditions of temperature.Having now experimented with 10 deliquescent chlorides (lithium, magnesium, cadmium, calcium, copper, nickel, cobalt, iron, manganese, and platinum), 3 nitrates (sodium, magnesium, and manganese) with sulphuric acid and with sodium formate, under various conditions, it was found that (1) they attract quantities of water corresponding in all cases to a definite hydrate, (2) after deliquescing to a maximum there followed in all cases a decline in weight and in four instances the salts returned to their original hydration and crystallised out, and that (3) the amount of hydration, though apparently always corresponding to a definite number of molecules of water, is not always the same, but seems to depend within certain limits both on the temperature and the relative humidity of the atmosphere and also on the conditions under which the air has access to the salt.The author suggests that the above experiments demonstrate the phenomenon of deliquescence to be caused by hydration of the deliquescent salt. W3. The fusion point, boiling point, and specific gravity of nitro-benzene.” By R. J. Friswell. Great discrepancies are found in the books as to the above constants. Schultz gives in his first edition, 1882, 1.2002 at 0’ and 1.1866 at 14.4’; in his second edition, 1.208 at 15’.Fusion point +3’. Beilstein gives the same, and quotes illitscherlich for the fusion point and Kopp for the specific gravity. Gmelin gives 1.209 and + 3O, and quotes Mitscherlich. As to boiling points, Gmelin, quoting Mitscherlich, gives 213O, Schultz, 1882, gives 148 points have been made. Calculated for comparison with water at are:grs.sp.the 4' t Cl Solid............... 1.5 1.3440 Liquid ............ 3.S 1,2220 ,, ........... 13.0 1.2160 ,, ............ 28.0 1.1931 210'; in 1886, 206-207', Beilstein quoting Stadeler, 205' at 730 mm. It would thus appear that several of these numbers have been quoted unverified for over 60 years.No statement of specific gravity of solid nitrobenzene has been pub- lished excepting that in TVcttts' Dictiomq, given to A. G. Green in private communication by R. J.Friswell. Determinationspf the various Boiling point corrected 209*Oo. Melting and solidifying point + 5'. Nitrobenzene is remarkable as having a distinctly coloured vapour very closely resembling that of chlorine. The colour is easily visible in a thickness of about 2 inches and is strongly marked when 6-8 inches are examined. The author is not, aware of any other organic vapour of so simple a constitution which is visibly coloured. No bands of absorption are shown in the visible spectrum when light is transmitted through this vapour. The violet and blue are absorbed as with the fluid but less strongly. "84."The action of light on a solution of nitrobenzene in con-centrated sulphuric acid." By R. J, Friswell. Nitrobenzene is, as has long been known, readily soluble in concen-trated sulphuric acid of 1.84 sp. gr. and upwards, but a comparatively small amount of dilution precipitates it and at about 1.7 the solubility is very slight. When a solution in pure concentrated acid is exposed to light it slowly darkens, T7V hen exposed to direct sunlight, the darkening goes on with great rapidity, and in a few minutes the solution becomes quite black and opaque, then the action ceases. Tho light from burning magnesium produces the same effect. The solution has been kept unchanged in the dark for upwards of four years.If the exposure to light takes place in a stoppered bottle, a slight odour of sulphurous acid is perceptible after some time in the air above the solution. If the nitrobenzene thus used is recovered and redistilled and re- dissolved in sulphuric acid it behaves in exactly the same way. Attempts were made to increase the change by spreading the solution on glass beads and between sheets of glass, but the depth of the colour of the product soon brought all change to an end. 149 Several hundred grammes of the black solution were prepared and attempts made to isolate the products of change, but though a brownish calcium salt was obtained and an ammonium salt in solution, the latter decomposed on evaporation with a caramel like odour ; what was left was treated with phosphoric chloride, but no satisfactorily pure product could be obtained : the matter needs further investigation.The rate of blackening of the solution is undoubtedly a measure of the actinic power of the light. DISCUSSION. Mr. A. G. GREENremarked.on the possible similarity between the action of sulphuric acid on nitrobenzene in the presence of light, and the electrolytic reduction of a solution of nitrobenzene in sulphuric acid which had been investigated by Gattermann. In this case it was shown that at first phenylhydroxylamine, then paramidophenol was the product. Dr. HEWITTsaid that he had noticed that coloration occurred in sulphonating nitrobenzene, even in the dark. The PRESIDENTdrew attention to the fact that in its changes of density near its solidifying point nitrobenzene appeared to show the same peculiarity as water, viz., an enormous change, but in an opposite direction.The action of light on the nitrobenzene solution in sulphuric acid was remarkable. If a flash of magnesium light were permitted to fall on the nitrobenzene solution through a quartz window, he thought that the blackening would furnish a good lecture illustration. Mr. FRTSWELL,in reply, said that he thought it quite possible that the change in the solution of nitrobenzene in sulphuric acid when exposed to light was of the same kincl as that induced by electrolysis. He had never observed any coloration on sulphonating nitrobenzene when the materials were pure and light mas excluded.85. The reduction of perthiocyanic acid.” By F,D. Chattaway,M.A,, and H. P. Stevens, B.A. The atoms forming the molecule of perthiocyanic acid have been assumed to be arranged in a simple ring from the observation that on reduction it yields thiourea and carbon bisulphide. As, however, the properties of the substance render it probable that its molecule is larger than that represented by the simplest possible formula, H,N,C,S,, the conclusion that in this complex molecule all the structural units have a similar atomic arrangeiiient is only valid if the amounts of thiourea and carbon bisulphide obtained on reduction approach those given by theory. The reduction of perthiocyanic acid has therefore been care- fully carried out in various ways to determine the exact amounts of carbon bisulphide and thiourea obtainable and the nature and amount of any other products of the action, 150 When perthiocyanic acid is reduced by tin and hydrochloric acid, carbon bisulphide and thiourea are produced in almost theopetical amount, H,N,C,S, +2H =CS(NH,), + CS,, only very small quantities of hydrogen sulphide and carbon dioxide are produced in addition, these being doubtless formed by the hydrolysis of a small portion of the perthiocyanic acid under the influence of the hydrochloric acid, H,N2C2S,+ 2H20=CS(NH,), +H2S+CO, + 8.86. '' The so-called hydrates of isopropyl alcohol." By T. E. Thorpe, LL.D., F.R.S. Four hydrates of isopropyl alcohol are stated to exist ;2C3H,0*H20, isolated by Erlenmeyer in 1863; 3C3H,0*2H20 and 3C,H,O*H,O, discovered by Linnemann in 1565; and C,H,O*H,O, prepared by Ruhemann and Carnegie in 1588.All these hydrates boil within a comparatively small range-from 7s"to 51°-whereas the amount of water they contain varies from 9 to 23 per cent. The author gives reasons for doubting the existence of these hydrates as distinct chemical entities capable of definite isolation. By studying the behnviour of mixtures of isopropyl alcohol and water, it would appear that within certain fairly wide limits, water and the alcohol distil together in indefinite proportions, and that the water tends to pass over more rapidly than the alcohol, and hence is found in the largest proportion in the fractions of lowest boiling point.There is no evidence for the existence of these hydrates at their respective boil- ing points. Nor is there any more evidence for their existence at ordinary temperatures. By synthetically forming them by the direct addition of the required amount of water to the alcohol, and allowing them to partially evapo- rate at the ordinary temperature of the air, it is found that the alcoholic strength of the residue is greatly increased; or, in other words, the water evaporates faster than the alcohol, although the latter boils 20' lower than the former. The two substances, therefore, are not in stable union, even at ordinary temperatures. When the relative densities of the synthetically formed 'hydrates ' are plotted in terms of the amount of water they contain, the values are found to lie on what is practically a straight line; or, in other words, the density of the mixture is, within the limits studied, very nearly a linear function of the amount of the constituents.87. "The carbohydrates of the cereal straws," By C. F,Cross, E. J. Bevan, and Claud Smith. This paper deals with the results of further investigations of the products of acid hydrolysis of the cereal straws and of the celluloses 151 isolated from them, including also the closely related esparto-cellulose. The results confirm those previously communicated (Trans., 1896, 69, 804-81 S), that the furfural-yielding constituents (furfuroids) are selectively attacked and for the most part (90 per cent.) dissolved ;also from the exceptionally high numbers for cupric reduction, that they must exist in solution in a fully hydrolysed form (monoses).The solutions when neutralised ferment with yeast ; carbonic acid and alcohol are produced, and a proportionate effect upon the constants of the solution is shown (density, opticity, cupric reduction, and furfural). Under the conditions, the proportion of the celluloses fermented amounts to 30 per cent. of the total dissolved solids. Similar conclusions are deducible from a recent paper by Tollens (J.fii~LaTedw., 1897, 106-107), in which the fate of malt-furfuroids in beer-fermentations is discussed. The experimental numbers in this paper show the disappearance of a large proportion of these constituents in the process.Since the pentoses entirely resist alcoholic fermentation, as shown by Tollens (Kohleirzlqclrate, ii), and further confirmed by the authors, as well as by later observations of Tollens privately communicated, it is evident that the group of furfuroids thus fermented is constitutionally distinct from the pentoses. Incidentally to observations on alcoholic fermentation with mixtures of known hexoses and pentoses, the authors find that the latter remain unaffected in presence of hexoses undergoing fermentation. Under certain conditions, however, the pentoses are removed from solution by the yeast organism; the necessary condition appears to be that of “ starvation,” in the sense, i.e., of the absence of hexoses.The dis- appearance of the pentose under these conditions is indicated by deter- minations of furfural and the fall of the furfural numbers. This phenomenon appears to be the simple one of assirnilation by the yeast organism, as shown by Bokorq (Diszgl. J.,1897, v, 303). The pentose undergoes constitutional change in such assimilation, as the yeast shows no increase in its normal small furfural number. The authors further discuss the question of the constitution of fur- furoids thus shown to yield to alcohol on fermentation, and conclude that the hypotheses of the existence of methylene ethers of the pentoses, OP pentose formals, affords, up to the point arrived at, a consistent view of their differentiation from t’he pentoses.The history of ‘‘piperonal,” C,H,T~/CH,, is cited in explanation /O\ ‘COH of the exceptional difficulty of arriving at positive final proof of the 0analogous constitutional formula C,H,O,<O>CH,, which sums up the 152 above hypothesis in relation to the group of furfuroids in question. The instability of the pentose as compared with the aromatic residue prevents the application of reactions of resolution (Fittig) or synthesis (Wegscheider) such as have established the methylenic constitution of piperonal. 88. ‘‘ Studies on the constitution of tri-derivatives of naphthalene No. 16. Conversion of chloronaphthalenedisulphonicacids into dichloronaphthalenesulphonic acids.” By Henry E.Armstrong and W. P. Wynne. In the course of their studies of naphthalene derivatives, the authors have had occasion to make great use of phosphorus pentachloride as an agent for displacing the SO,H radicle by chlorine. It was therefore necessary to establish in every possible way the .validity of this method of determining constitution in the naphthalene series, as it is obvious that the occurrence of isomeric change in any one case would materially weaken the force of all arguments based on its application. With regard to the nature of the interaction, it is to be noted that, in a previous communication (Proc., 1895, 11, 83), it has been shown that it is usually possible to dispense with the pentachloride, and to obtain the chloronaphthalene corresponding with the given sulphonic chloride by merely heating the latter alone under appropriate condi- tions, but that as a rule the chloronaphthalene is obtained somewhat more readily and in larger relative amount when the pentachloride is used.In other words, the main function of the pentachloride is to pro- mote the elimination of SO2 from the S0,Cl radicle. In the case of the chloronaphthalenesulphonic chlorides, the amount of dichloronaphthalene obtained by means of phosphorus pentachloride is relatively considerable, and the residue left after its removal from the crude product by distillation with steam yields nothing but the original chloronaphthalenesulphonic acid on hydrolysis. The chloronaphthalenedisulphonic chlorides, however, behave some- what differently, affording but a comparatively poor yield-rarely exceeding 30 per cent.of the theoretical amount-of trichloronaphtha-lene. While preparing a full account of their work, the authors have felt it to be incumbent on them to thoroughly examine the residues left after separating t,he trichloroiiaphthalenes, which they have had occasion to produce on a large scale (Proc., 1895, 11,S6). Although, in view of the uniformity of the end-products, it mas improbable that any change in orientation had taken place at the somewhat high tem- peratures at which the interactions were effected, it was obviously im- portant to ascertain in every possible way whether such was the fact. 153 The results to be recorded are of interest, as they serve in every case to justify the conclusion previously arrived at, that the treatment of sulphonic chlorides with phosphorus pentachloride may be thoroughly trusted as a means of determining constitution in the naphthalene series, Two cases may be quoted as typical of the behaviour of chloro-naphthahedisulphonic chlorides in general.When 2-chloronaphthalene 4' :2'-disulphonic chloride (Proc., 1890, 6, 129) is heated with the theoretical quantity of phosphorus penta- chloride at 175" during 2 hours, it yields both 2 :4':2'-trichloro-naphthalene and 2 :4'-dichloronaphthalene-2'-sulphonic chloride in about equal proportions, about 50 per cent. of the material remain- aciding unchanged. 2 :4-Dic?~loronc~~~thcLlene-S'-sulpT~onic affords a sparingly soluble barium salt, crystallising with 34 molecular propor- tions of water in microscopic needles ; a sparingly soluble potccssium salt, containing 1Q molecular proportions, in thin scales ; a chloride crystallising from benzene in small prisms melting at 156" ;an amide crystallising from dilute alcohol in slender needles melting at 196" ; and when the chloride is heated at 180-185O with phosphorus penta- chloride it is converted into 2 :4':2'-trichloronaphthalene.On hydro- lysing the chloride in sealed tubes with concentrated muriatic acid at 290°, or the potassium salt with a mixture of sulphuric and phosphoric acids and superheated steam, 2 :4'-dichloronaphthalene is obtained. The ceurse of change may therefore be thus represented : c1~~so2c1 c1pp,c1 + c1/\)So,c1 + ] ! I\/\/ \/'\/\Ivc1 S0,Cl c1 When 2-chloronaphthalene-1' : 3'-disulphonic chloride (Proc., 1890, 6, 13) is similarly heated with phosphorus pentachloride, it yields, besides 2 :3' : 1'-trichloronaphthalene,a somewhat larger proportion of a mixture of 2 :l'-dichloronaphthalene-3'-sulphonicand 2 :3'-dichloro-naphthalene-l'-sulphonic (Proc., 1890, 6, 84) chlorides, about 50 per cent.of the material remaining unchanged. 2 : 1'-Diclzloyonaphthalene-3'-su,?phonic acid, the isomeride present in the larger proportion, yields an anhydrous potassium salt, cry stallising in thin, elongated scales, but exhibiting a tendency to separate in a gelatinous form; a chloride crystallising from benzene and light petroleum in small prisms melting at 130O; and an amide crystallising from dilute alcohol in slender needles melting at 21s".When the chloride is heated at lS0-185° with phosphorus pentachloride, 2 :1' :3'-trichloronaphthalene is formed. On hydrolysing the chloride in sealed tubes with concentrated muriatic acid at 290°, or the potassium salt mixed with sulphuric and 154 phosphoric acids, in superheated steam, 2 : 1’-dichloronaphthalene is obtained. The course of change may therefore be thus represented : c1 The other a-P-disulphonic chlorides behave similarly, the tendency being, however, as in the first of the above instances, to form only one of the two possible isomeric dichloronaphthalenesulphonicchlorides, no doubt because the SO, of the 80,Cl ra.dicle, like the SO,H radicle, is more easily displaced from a-than from P-positions.It is not certain that these products are intermediate in the strict sense of the term, as the effect of prolonging the heating with phosphorus penta- chloride at the minimum temperature at which the reaction takes place serves only to increase the yield both of the dichloro- and trichloro-derivatives. As the dichloronaphthalenesulphonic chlorides produced in these interactions decompose at temperatures a few degrees higher-10’ to 15’ in most cases-than those at which the corre-sponding chloronaphthalenedisulphonic chlorides from which they are obtained undergo change, it is not difficult to understand why they escape attack by phosphorus pentachloride under the conditions observed.89. Conversion of 1 : 1’-into 1 :4’-dichloronaphthaleneby hydrogen chloride. The products of hydrolysis of 1 : 1’-dichloronaphtha-lene-3-sulphonic acid.” By Henry E. Armstrong and W. P. Wynne. When 1: 1’-dichloronaphthalene is heated with concentrated muriatic acid at 290°, it is wholly converted, save for a trace of carbonisation, into the isomeric 1:4’-dichloronaphthalene. This remarkable isomeric change does not seem to occur at temperatures below 200°, but is noticeable at 250’, and complete at 290’; it does not occur when 1:1’-dichloronaphthalene is heated either alone, or with water, or with concentrated phosphoric acid at 300°,but does happen when it is heated with sulphuric acid of a strength to cause considerable carbonisation.None of the isomeric dichloronaphthalenes show any tendency to change under these conditions. . The experiments which led to these results were made in consequence of the perplexing behaviour of 1: l’-dichloronaphthalene-3-sulphonic acid on hydrolysis. The isomeric a-sulphonic acid (Proc., lS90, 6, 81) requires only a temperature of 230’ to effect its hydrolysis, and gives only 1:1’-dichloroiinphthalene,whatever be the hydrolytic agent used ; the P-sulphoiiic acid, on the contrary, is not hydrolysed below 285O, and 155 according to the agent used gives one or other of no less than three dichloronaphthalenes. 1 :1‘-Dic~l~onaphthcclene-3-su~~~onicacid is obtained in addition to about an equal proportion of 1 :1’:3-trichloronaphthalene when 1-chloro-naphthalene-1’ :3-disulphonic chloride (Proc., 1890, 6, 16) is heated with phosphorus pentachloride at 160” (compare preceding abstract).It forms a sparingly soluble, anhydrous potassium salt crystallising in thin, elongated scales ;a chZom2e crystallising from benzene in thin scales melting at 158O; an arnide crystallising from diIute alcohol in short, slender needles melting at 197O ;and 1:1’:3-trichloronaphthalene when its chloride is heated either with phosphorus pentachloride at 170°, or alone at 200-230”. On hydrolysing the potassium salt with dilute acids such as 1per cent. sulphuric acid or 50 per cent. phosphoric acid at 290°, about 5-10 per cent.of the theoretical quantity of 1 :1’-dicbloronaphthalene is obtained, the residue being unchanged salt -a result by which the constitution of the acid is determined beyond doubt. When heated with 5 per cent. sulphuric acid or 60 per cent. phosphoric acid, carbonisation largely occurs, and with these and stronger acids a small amount of 1:4‘-dichloronaphthalene is the only substance obtained, a better yield-some 20 per cent. of the theoretical-being got when the chloride is heated with concentrated muriatic acid at 290’. The production of 1:4’-instead of the expected 1:1’-dichloronaphthalene under these conditions is to be referred to the action of hydrogen chloride, either present or formed during the carbonisation of the salt.On effecting hydrolysis by heating the potassium salt, mixed with sulphuric and phosphoric acids, in superheated steam instead of in sealed tubes, an unexpected result was obtained, pure 1:2’-dichloro-naphthalene, to the extent of 40 per cent. of the theoretical amount, being the product, the remainder of the salt being carbonised. The explanation of this change has yet to be given. It is certain that the 1 :2’-compound is not an intermediate step in the conversion of 1:1’-into 1:4’-dichloronaphthalene during hydrolysis in sealed tubes, both because it is unaffected by prolonged heating with concentrated muriatic acid, and because 1 :2’-dichloronaphthalene-3-sulphonicacid cannot be detected in the material which has escaped hydrolysis, and, moreover, behaves normally on hydrolysis (compare preceding abstract). It is possible that, under the conditions specified, further sulphonation may precede hydrolysis, and that in consequence of the transference of chlorine to the para-position being thereby prevented, 1: 2’-dichloro-naphthalene is formed, thus : c1 c1 c1 c1 c1 c1 156 Further experiments are being made to test this view, Of the trichloro-naphthalenes, the 1: 2 : 8-modification is the only one which undergoes change when heated with concentrated muriatic acid.Its sulphonic and disulphonic acids behave similarly, but the course of the action has not yet been worked out, owing to want of material. 90. “Note on the formation of diacetanilide.” By George Young, Ph.D.The introduction of a second acetyl group into acetanilide has been described in recent years by several authors. Kay (Bey., 1893, 26, 2853) treated acetanilide with acetyl chloride at 170-180O from 3 to 4 hours. Bistrzycki and Ulffers (Bey., 1894, 27, 91) heated a mixture of,acetanilide and acetic anhydride, under pressure, 8 to 10 hours at 200-205°. Blacher (Bey., 1895, 28,2356) boiled sodio-acetanilide suspended in xylene with acetic anhydride. Tassinari (Gazx., 1894, 24,i, 61) acted with acetyl chloride on sodio-acetanilide suspended in benzene. The English and -German abstracts of Tassinari’s paper state that this author also prepared diacetanilide by treatment of acetanilide with acetic anhydride, but the following quotations from the original paper show that the method used consisted in boiling a mixture of acetanilide, acetic anhydride, and sodium acetate on a reflux apparatus for some hours.In the introductionto his paper, Twsinari makes the general statement, “le diacidanilidi xi formano anche con anidride acetica ed acetato sodico a ricadere.” It is true that in describing the preparation of diacetanilide, he does not mention sodium acetate-“ Trattando dell’ acetanilide con anidride acetica, come 1! detto sopra per la formanilide . . . ,” but the passage referred to runs : 6‘ Scaldando a ricadere per alcune ore un misto di formanilide, anidride acetica, ed acetato sodico. . , .” Further, in a later paper (Guzx., 1894, 24, i, 444) in which the work of Bistrzycki and Ulffers is quoted, no notice is taken of a statement by these authors (Zoc.cit.) that, although acetanilide undergoes some change when boiled for 2 hours with acetic anhydride, they were unable to obtain any pure product from the reaction. The introduction of the second acetyl group takes place much more easily than might be imagined from the results quoted. If acetanilide be boiled with 2 to 3 times its weight of acetic anhydride for half an hour, over 75 per cent. is converted into the diacetanilide, which may be easily purified by the following method. The cooled product is shaken with benzene and sodium carbonate solution. After drying over calcium chloride, the benzene solution is distilled as far as possible on the water bath, and the residue treated with light petroleum.The unchanged acetanilide is removed by filtration, and the filtrate evapo- rated. The residue solidifies on cooling to a crystalline mass, melting at 37-38", A single recrystallisation, by extraction with cold light petroleum and evaporation of the extract, is sufficient to purify it for analysis, when it melts sharply at 38". 0.1792 gave 0.4449 CO, and 0,1025 H,O. C=67*71; H=6.35 2. C,H,N(COCH,), requires C = 67.79 ; H = 6.21 per cent. Part of the diacetanilide formed is probably hydrolysed by the treat- ment with sodium carbonate solution, but by working with not too large quantities, and performing the purification as rapidly as possible, a yield equal to the weight of acetanilide taken may easily be obtained. 91.Derivatives of phenetol azo-phenols." By J. T. Hewitt, M.A., D,Sc., Ph.D., T. S. Moore and A. E. Pitt. One of the authors has shown (Bey., 1895, 28, 799) that certain substitution derivatives of benzeneazophenol can form addition pro- ducts with half a molecule of water, differing very sharply in colour and other physical properties from the corresponding anhydrous com- pounds. In order to obtain further knowledge of this subject, various series of substituted benzeneazophenols are being prepared and examined, This communication deals with ortho- and para-phenol azophenols, C,H,O*C,H**N:N*C,H,OH, the examination of the meta- derivative being deferred. When a paraoxyazo-compound does form an addition product with water, the addition of the latter.can be most frequently brought about by dissolving the azo-compound in benzene and precipitating it by gaseous hydrogen chloride as a hydro-chloride of the general formula, X -N:N*C,H,OH,HCl, and decom- posing this with water. Frequently the molecule of hydrogen chloride is thus replaced by a half molecule of water. Odiophenetolusophenol was prepared according to the method given by Jacobson and F. Meyer (AnnaZen, 1895, 287, 213). The melting point was found to be 128" C. (corr.), Jacobson gives 131" C. The hyd~ocldo~idemelted between 124"and 129" C. On decomposition with water, the azophenol was regenerated; after air drying it melted at 127-128". It may be assumed that no water had been added.In order to further characterise the azophenol, the two following derivatives were prepared. U,H,O C,H,*N :N C,H,* 0.COC,H,01.tho~~~ezzetoZaxo~l~e~~~l~enxonte, light scarlet needles, m. p. 98O (corr.). O?.thoZ?i~enetoZcxo~~~en~Z~enene suZplbonate, CaH50*C,H;N:N*C,H,.O.SO,C,N,, brilliant red needles, m. p. 83" (corr.). Pcrc~l~enetol~xo~l~enolhas been prepared by IZiedel (D.€2. P.,48, 453), and also by Jacobson and F. Meyer (Azm., 1895, 287, 215). The fornier gives the melting point as 104.5" C., the latter as 125--12G0. Tlie method of the latter chemists wiis used to prepare the compound. 158 The melting point was found to be 125" (corr.). The hydvocldoride gave no very sharp melting point, beginning to melt at 131", fusion not being complete until 154".On treatment with water, a pale yellow powder is obtained melting at abont 100". The same substance may also be obtained by clissolving phenetolazophenol in glacial acetic acid, ndcling fuming hydrochloric acid, and pouring into water. After care- ful drying in air the substance melted at 104-109' C. Apparently this substance consists of equimolecular proportions of water and para- phenetolazophenol. Cdc. C,,H,,N,O, ,H,O Pound. Mean. 0 ............ 64.62 65.10 64-49 64.39 64.68 XI ............ 6.15 6.40 6.29 5.95 6.21 The following derivatives of paraphenetolazophenol have been pre- pared. Yuruz~henetokaxo~henyl acetate, C2H,0 C6H4*N: N*C,H,*0 COCH,, yellow leaflets, m. p. 11So (corr.).Pa?.cc~~~~e.netoZnxophen~lbenzoate. C,H,O.C,H,.N:N.C,H,O*COC,H,, small reddish brown crystals, m. p, 126" (corr.). Pccra~~?~enetoZaxop~en~~~e~~~enesulphonccte, C2H,O*C,H,*N:NC,H,*0SO2C,E large, pale yellow plates, m. p. 104' (corr.). (692, 8-Ketopinic acid and camphoic acid." By W. S. Gilles and F. F. Renwick, In the description first given of ketopinic acid (cf. Armstrong, Trans., lS96, 69,1397), it was stated that the acid was optically inactive, even when prepared by oxidising the most active chloro- camphydrene (pinene hydrichloride) obtainable. As it was a matter of importance to determine whether the inactivity was an inherent property or due to compensation, the authors have applied Pastsur's method, and have succeeded in separating a dextrorotatory modification by fractiorially crystallising the mixture of salts obtainetl by combining the inactive acid with strychnine. 6-Ketopinic acid has the same melting point as the "inactive " acid from which it is separated.In their previous note (Proc., 1807, 14, 64) the authors have stated that when ketopinic acid is oxidised by permanganate it is converted into a tribasic acid resembling the carnphoic acid described by Marsh and Gardner; they are now able to state that the product is carnphoic acid, having obtained from it the cis- md trans- cnmpliopyric acids and camphopyric anhydride of these chemists. An amount of cnmphoic acid equal to 80 per cent. of the weight of the acid oxiclised may be obtained by boiling ketopinic acid with a solntion coritaiiiiiig 50 per cent.of nitric acitl and adding small quan-tities of stmmgei* acid (d= 1.42) from time to time, as the action proceeds. 169 The authors will endeavour to ascertain if pinophnnic and cnmphoic acids also exist in optically active forms, and what is the behaviour of active ketopinic acid on oxidation. Acids which are probably cis-and trccns-forms of pinophaiiic acid have already been obtained. 93, Note on stereoisomeric di-derivatives of camphor, and onI' nitrocamphor." By T.M.Lowry, B.Sc. Having learnt from Dr. Armstrong that, in the course of his early studies of camphor derivatives, he had observed that the snbstances obtained on the one hand by chlorinating bromocamphor and on the other by broininating chlorocnmphor are apparently different, the author has submitted the two products to examination.Brominated chlorocamphor, according to Cjazeneiive, niclts ij t 5 1 ~5". The author finds that, on warming a mixtnro of chlorocnmphor :tnd bromine and once crystnllising the product from spirit, .cvelI-defiiletl crystals are obtained which melt at 53-55"; on analysis, these give results showing them to be bromo-chlorocamphor. By repeated re-crystallisation from R variety of solvents, this product, lio~vever, may be resolved into two fractions, alike in composition, but widely different in specific rotatory power. Thc less soluble product, aftel- being twenty- five times recrystdlised, fused at 61' ; its specific rotatory power was [a],, = 16'.The more soluble fraction-obtained by evaporating the mother liquor, distilling the residue with steam and recrystallising the product from dilute spirit-fused at 55" ; its specific rotatory power was [a] = 63.9". On directly chlorinating bromocamphor, an oil was obtained which could not be caused to crystnllise ;but a crystalline chlorinated bromo- camphor was obtained without difficulty by heating bromocamphor with sulphuryl chloride at 130". After being twice crystallised from spirit, the product fused at 56" ;its specific rotatory power was [a],, = 25.7" instead of 51'-the value observed in the case of the correspond- ing product from chlorocamphor. As in the former case, by repeatedly recrystallising this product, a less soluble fraction was separated melt- ing at 61*5', the specific rotatory power of which was [.ID = 10.3'; the more soluble fraction from the mother liquor had the specific rotatory power [a]D=28-30.There can be no doubt that the two products examined were isonzorphous mixtwes of constituents differing slightly in solubility but widely in specific rotatory power, careful study of the crystalline properties showing the constants to bo nearly identical in the two cases. As both yield nothing but ordinary chlorocamphor on reduction, it follows that, in each case, the apparently simple product is :L mixture of the two stereoisomeric aa-chlorobromocamphors : C,H,,<i C<"lBr C,H,,<?<C! Br 1cc) CO 160 These observations, in fact, undoubtedly afford the proof hitherto wanted, that in the ordinary derivatives of camphor containing halogens, the halogen atoms are both associated with the same carbon atom.A careful examination both of ordinary dibromocamphor and of nitro- bromocamphor has also been made, the result of which is that neither of these is resolvable into isomorphous constituents. The author finds that wheh nitrobromocamphor is reduced by means of an alcoholic solution of potash, a nitrocamphor is obtained which has the properties attributed by Cnzeneuve to that prepared from nitrochlorocamphor ;the substance obtained by R. Schiff must have been impure. By the action of bromine on nitrocamphor dissolved in acetic acid, bronionitrocamphor is reproduced-not the compound C,oH,,Br2N,011, which, according to Schiff, is obtained on subjecting the potassium salt of nitrocamphor to the action of bromine.Nitrocamphor appears to be a birotatory substance, its rotatory power in solution diminishing to a considerable extent as time proceeds -thus, a solution in benzene containing 10 per cent. of the substance, gave as initial value [a], = -112*4O, but after 3 hours -1025"7, and at the expiry of 22 hours, when the rotatory power no longer changed, -865". A further observation of interest has been made, viz., that when a solution of nitrocamphor in benzene is evaporated on the water bath, and the residue is further heated during about an hour, a product is obtained which is less soluble than the original nitrocamphor, and which melts at 190" instead of at 103".The same substance is formed on heating fused nitrocamphor slightly above its melting point. The specific rotatory power of this substance in benzene (a 5 per cent. solution) is [aID = + l87", and in chloroform + 167'. 94. The interaction of ethylene dichloride and ethylic sodio- malonate." By Bevan Lean, D.Sc., B.A., and Frederic H. Lees. It has been shown by Prof. Perkin that, whenethylene dibromide is acted on with ethylic sodiomalonate, the chief product is 1 : 1-ethylic CH,Brtrimethylene dicarboxylate (208-210°, 760 mm.), thus : ($@r i-2CHNa(COOEt) -CH2>C(COOEt), +CH,(COOEt), +3NaBr. In a -6H2 later paper, he has shown that a smallquantity of an oil of high melt- ing point is formed, viz., ethylic butanetetracarboxylate (b.p. 240°, 40 mm.), and he has represented the action thus : Z(COOEt),CHNa + BrCH,. CH,Br = (COOEt),CH* CH,. CH,*CH(COOEt), + 2NaBr. In later papers, he has shown that by substituting ethylene chloride for ethylene bromide the yield of ethylic butanetetracarboxylate can be 161 materially increased, and it has been proved by Bone and Perkin that the action is represented by the equation (COOEt),CH, +CH2>C(COOEt), =(COOEt),CH* CH,. CH,. CH(COOEt),.CH,,5 a B a The authors now show that at the same time small quantities of ethpZic butcc~etrica~*boxyZccte,(COOEt),CH* CH,. CH,* CH,* COOEt (b. p. 200-205°, 40 mm.) and etluylic adipate (b. p. 245", 760 mm.) are formed.They attribute tho formation of these two substances to the action of sodium ethoxide (or perhaps sodium hydroxide, since the materials cannot be entirely free from moisture) upon ethylic biitnnotetracarboxylate. It cannot be doubted that a similar action is of frequent occurrence, in greater or lesser degree, whenever substances containing two alkylic carboxylic groups attached to one carbon atom are treated with haloid compounds in the presence of sodium ethoxide. The following derivatives have been obtained from ethylic butanetricarboxylic acid. EtJb@'c a-et7~~Zbutanetl.ical.hox~l(~te, (COOEt),CEt*CH,* CH; CH,. COOEt, a colourless oil, b. p. 200-202", 32 mm. Montemartini (Abstr., 1897, '72, 19), has also prepared it ;he gives the b.p. 205-208" at 35 mm. a-Et~~?/Z6utanetricai.box~Zicacid, (COOH),CEt*CH,* CH,*CH,*COOH, white crystals, m. p. 155-158". Montemartini describes it as an oil. a-Eth?/Zdipic cccid, COOH*CHEt*CH,* CH,. CH,* COOH, white crystals, in, p. 48--50° (Montemartini, 46-49'). 95. (( Hexanaphthene and its derivatives. Preliminary note." By Emily C. Fortey, B.Sc. In view of work now being carried on with respect to the naphthenes (Markomnikoff, Ber., 1897, 30, 974, 1211, R.C. ; Zelinsky Be?.., lS97, 30, 387, 1532), the author wishes to give a short account of some results as yet incomplete on hexmaphthene and its derivatives. The substance was obtained from American light pctroleurn by fractional distillation with the aid of a long fractionating column made by Professor Sydney Young, and precisely similar to the one described by him (Chenz.News, 1895, '71, 177). Benzene and toluene were removed by prolonged treatment with a mixture of strong nitric and sulphuric acids. The hydrocarbon finally obtained (after 33 distillations) was not quite free from paraffins, but the purest fraction which boiled at 80.55-S0.65" and had the specific gravity 0.7722 at Oo/Oo, gave, on analysis, the following result as the mean of three determinations: C, 55-23; H, 14.60. Calculated for C,H,, : C, S5.72; H, 14.28. The liquid boiling within 0.4 of a degree was chlorinated by means of a current of chlorine in presence of iron, and a mixture of di-, tri- and *tetrachlorhexanaphthenewas obtained. By the action of alcoholic potash on the fraction boiling at 135-140" 162 under a pressure of 30 mm., consisting chiefly of trichlor-hexannphthene, hydrochloric acid was eliminated and the formation of a small quantity of benzene mas proved by nitrating it and reducing the nitrobenzene to aniline, which gave the characteristic coloration with bleaching powder solution.Benzene having thus been obtained from hexa-naphthene, the identity of the latter with hexamethylene is no longer questionable. A small quantity of benzene hydrochloride, C,H,Cl, was also obtained by the action of alcoholic potash on trichlorhexanaphthene. It boiled at 135-140°, and an analysis gnve the following result : C, 63.20; H, 5-91;C1, 30.36. Calculated for C,I-P,Cl : (3, 62-93;H, 6.12 ;C1, 30.95.Hexanaphthene, when heated with fuming nitric acid, mas found to be oxidised to adipic acid, as stated by Markomnikoff (Ze7*., 1897, 30, 975). As both this chemist and Zelinsky appear to have obtained methyl pentainethyleiie by the action of hydriodic acid on derivatives of hexanaphthene (Rer., lS97, 30, 3S7, 1214), it became of interest to see whether the hydrocarbon itself would undergo isomeric change under similar conditions. Hexanaphthene boiling at $O.O-SO*l O was therefore heated 'in a sealed tube with about five times its volume of hydriodic acid, sp. gr. 1.96, and a little amorphous phosphorus. The tube mas heated to about 160" for 6 hours, from 250" to 270" for 3 hours, and was maintained at about 250" for 4 hours longer.The hydrocarbon, after being washed and dried, boiled almost constantly at SOo, showing that it was unchanged hexamethylene. Zelinsky has found that methylhexamethylene is converted into dimethylpentamethylene by heating with hydriodic acid (Ber., lS97, 30, 1532), it is therefore interesting to note that hexamethylene itself appears to be much more stable than its derivatives. It is hoped to obtain a fresh supply of the substance by the fractional distillation of Gnlician petroleum, when the experiments will be continued. ADDITIONS TO THE LIBRARY. I. By Purchase. Lafar, Franz. Technische mykologie, cin handbuch der Gkungs- physiologic Erster Band. Pp. xii + 362. Jena 1897. Xaare, 0. Die fabrikation dcr Kartoffelstarke. Pp. xii + 5'77.Berlin 1897. 11. Donations. Eedford, the Duke of, and Pickering, S. U. Report on the working and results OF the Woburn Experimental Fruit Farm since its establish- ment. First ICcport. Pp. iv+ 194. London 1897. From the Authors, 163 Urookshank, E. &I. A Text-book of Bacteriology, including the Etiology and Prevention of Infective Diseases. Fourth edition. Yp. xxx + 715. London 1896. From the Author. Hantzsch, M. A. Pr6cis de StArdochimie. Pp. 223. Paris 1896. From the Publishers. LIBRARY. The Library will be closed during the last fortnight in August for cleaning and the annual revision of the Catalogue. Fellowsare requested to return all books in their possession not later than August 9th. RICHARD CLAY AND SONS, LIMITED, LONDON AND BUNGAY.
ISSN:0369-8718
DOI:10.1039/PL8971300141
出版商:RSC
年代:1897
数据来源: RSC
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