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Proceedings of the Chemical Society, Vol. 21, No. 301 |
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Proceedings of the Chemical Society, London,
Volume 21,
Issue 301,
1905,
Page 277-300
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摘要:
PROCEEDINGS OF THE CHEMICAL SOCIETY. VOl. 21. No.301. Thursday, December 7th, 1905, at 8.30 p.m. Professor K.MELDOLA, F.R.S., President, in the Chair. Mr. T. W. Firth Clark was formally admitted a Fellow of the Society. Certificates were read for the first time in favour of Messrs. : George Ernest Banner, Brooklyn, Highfield Rd., Rock Ferry, Cheshire. Arthur Ernest Barker,B.A., B.Sc., 3, York Rd., Chorlton-cum-Hardy. Charles Frederick Polwhele Bletchley, B.A.,Downside College, Bath. Arthur Forbes Braid, Rose Mount, Dumbreck, Glasgow. William Caldwell, M.A., Mont-Cecil, Bloomfield, Belfast. Reginald William Lane Clarke, 15,Torridon Rd., Hither Green, S.E. William Boulton Clonyingham, ‘‘ Sandon,” Ballsbridge, Go. Dublin. Frederick Watkins Evans, S, Charlotte Street, Hull.Hans Eduard Fierz, Ph.D., Clydach-on-Tawe, Glamorg., Wales. William Henry Matthews Jones, Leyden Villa, Chester. George Frederick Wesley Martin, 14, Castle Park, Lancaster. John Edmund Pitman, B.8c., Hartley Univ. College, Southampton. Harold Rogerson, M.Sc., 46, Bloomsbury St., Beclford Sqiiare, W.C. Frank Smith, B.Sc., 407,Church Road, Smithills, Bolton. Percy Charies Thornton, 9, Cantwell Road, Plumstead, S.E. Ronald William Tonkin, 37, Oakill Road, Putney, S.W. Elkan Wechsler, Ph.D., 59, Petherton Road, Canonbury, N. A ballot for the election of Fellows was held, and thc following were subsequently declared duly elocted : Adam Lnwson Kelly Adam. Williani McCleary. C. Chester Ahhim. Robert Drysdsle MacKechnie. James Edward Alcock.Harry Martin. James Albert Allison. Harry George Fletcher Mickle-Charles Anthony, inn. wight, B.A. George Henry Earbrook. John Dnnlop Millen. Marrnaduke Barrowcliff. Eclalji Nlanekji Modi. John Coggin Brown, B.Sc. Eric Haydn-Morris. Bryce Chndleigh Burt, l3.8~. John Notion. Joseph Edward Coates, l3.S~. Henry Allen Dtigdale Keville, B.Sc. Douglas Henry Rellars COWIYIRII. Francis Richard Penn. Arthur Anguqtine Dallman. H~igliDonald Pcrkinq. Joseljh Morgan Davey. Percy Barltcr Pliipscn. John Llewelyn Davies, 13. A. Fredrrick John Pooler, 13, Sr. John Doull. Thomns Rigby. Harry Dunlop. Jaines Frederirk Fothergill Rcou -John Beaconsfield Gall. land, H.A. Sidney Montaaue Haig. Henry Rowley. Alfred Hart, M.A., R. Sc. Harold Marrnion Royle. Jack Vernon Johnson Haynian. Arthur Gough Ruston, B. A., 13.S~. John Michael Higgins. Harry Nestor-Schnurmann. William Basil Hill. Douglas Temple Setterington. Isaac Berkwood Hobsbauin. John Booty Tillot. Cecil Hollins. Frank Tutin. Maurice Brooks Jack. George Stanley Walpole, 13 Sc. Edward Towyn Jones, B.Sc. John Ledger White, D.Sc. Herbert Drake Law, J3.Sc. Gerard Williain Williams, €3. A., Rudolph Lyon. Of the following papers, those marked * were read : “202. “The constitution of nitrites. Part I. Two varieties of silver nitrite.” By Prafulla Chandra Rky and Atul Chandra Gaiiguli. It has generally been maintained that silver nitrite has a nitronic or non-oxylic constitution (Divers, Tram., 1883, 43,455 ; 1885, 47, 205), but Emerson Reynolds seems, however, to be of opinion that ‘‘isomeric metallic nitrites of both the types (ouylic and imidic) exist which are also tautometric in a marked degree” (Trum., 1903, 83, 643).The close analogy between mercurous nitrite and the corresponding silver compound has all along been pointed out in some of the authors’ previous memoirs, and it would appear that under the action of heat the former behaves as if it had a twofold constitution, as indicated by HgNO, and Hg*O*NOrespectively (Tram., 1903, 83,491). 270 In the present communication, the authors hope to establish that silver nitrite also has this dual character, the two varieties being now described under t,he designation of a-and 8-compounds re-spect ivelg.The a-Tariety of SiZve~Nitde.--This is the substauce prepared by double decomposition between solutions of silver nitrate and sodium nitrite. The precipitate, consisting of a mealy crystalline powder, is drained at the pump, thoroughly washed with cold water, and dried under diminished pressure over sulphuric acid. The method of experiment was exactly the same as already described (Trans., 1905, 87, 180). In the experiment of Divers and Shimidzu, after the apparatus had been exhausted the flow of mercury in the fall tube was stopped so as to allow the nitrous fumes evolved during the heating of the salt to act on the metallic silver set free, thereby favouring the formation of silver nitrate and nitric oxide (T~ccrzs., 1885, 47, 634). In the present instance, the reverse method was followed.The rate of the flow of mercury was increased during the operation. By this arrangement the nitrous fumes were swept out of the tube almost as fast as they were generated, thus giving them much less chance of coming into contact with the silver. Moreover, these being absorbed by the caustic potash in the spiral, not only was the ‘‘ soiling ” of mercury in the Sprengel pump guarded against, but also the formation of nitric oxide by the secondary reaction between mercury and nitrous fumes prevented. As it was desirable that the heating should be effected at a definite temperature, an asbestos box was made fitted up with mica windows; when the bath had reached the required temperature, the portion of the glass tube containing the substance was introduced into it through an opening.The various stages in the decomposition could also be easily watched through the mica plates. The salt, when heated at temperatures ranging between 220’ and 250°, fused, evolving red fumes. The gas which was collected in the reservoir of the pump was completely absorbed by a solution OF ferrous sulphate, thus proving it to be nitric oxide. The residue solidified into a hard I~imp, consisting of a mixture of metallic silver and its nitrate. So far as this experiment goes, Divers’ results are confirmed. The silver nitrite breaks up according to the equation : 2Ag*NO,=2Ag +N,O, (1) ; at the same time, a portion of the silver thus set free acts upon the nitroiis fumes, giving rise to silver nitrate and nitric oxide : Ag +NO(N0,) =AgNO, +NO (2).The p-fiwiety of Silver ATitrite.-The silver nitrite as prepared above is dissolved in boiling water, and from the hot saturated solution the nitrite is allowed to crystallise ; when the mother liquor becomes luke- warm, it is decanted into a shallow evaporating dish. When left over- 280 night, slender needles are formed, which are drained and dried as above. The heating was effected at exactly the same temperatures as in the preceding experiment, namely, between 200' and 250'. Very slight red fumes were noticed, and the substance did not fuse. The gas col- lected was not absorbed or coloured by a solution of ferrous sulphate, but was completely absorbed by a solution of alkaline pyrogallate, thus proving to be oxygen.As the salt did not fuse, the filamentous character of the original crystals was kept intact; the residue, on treatment with hot water, did not give the faintest opalescence with hydrochloric acid, and, when struck with a hammer, it solidified into a shining regulus of metallic silver. The results are noteworthy in more respects than one. In the present instance, any formation of silver nitrate is out of the question. This salt is a stable compound, and it decomposes only slightly even at 444" (Divers, Trans.,1899,75, 83). It cannot, therefore, be urged that a little silver nitrate is at first formed, which breaks up and yields oxygen according to the equation : 2AgK0, =2Ag +N,O, + 0,.The oxylic constitution of silver nitrite, however, offers an easy explanation. Under the action of heat, the scission takes place as indicated by the dotted lines : Ag-0-NO... Thus, from every two molecules of silver nitrite two molecules of nitric oxide and one molecule of oxygen are simultaneously set free. Now, although a, mixture of these two gases in this proportion probably gives rise ordinarily to the peroxide, when it is rapidly drawn through or shaken up with a solution of caustic potash, the whole of the oxygen is not fixed, and a portion of it escapes uncombined. In short, the success of Gay-Lussac's method of preparing potassium nitrite is based on this fact (Trans.,1899, 75,85).It is also remarkable that although a slight quantity of nitrous fumes was noticed, not a trace of silver nitrate was formed under the conditions present. Some dozen experiments were performed with samples of silver nitrite from separate preparations confirming the above results. We give below the result of one typical experiment. 0.43 gram of salt gave 0.3 gram of silver and 35.2 C.C. of moist nitrogen (extracted from the alkali in the spiral) at 32.5" and 754 mm. Found* Ag =69.76; N =8.70; calculated Ag =70.13; N = 9.09 per cent. The ratio of nitritic to nitratic nitrogen was as 5 :3.8. The oxygen collected was 2.6 C.C. at the above temperature and pressure.? * The percentages of nitrogen aid silver are rather low, but it should be remem- bered that the crystals, from the method of preparation, necessarily coiltailled a trace of included mother liquor.t If the whole of the oxygen were ahsorbed, the alkali, on examination, would have yielded nitritic and nitratic nitrogen in oqiial qnantities. A few espeyiments 281 In conclusion, the authors wish it to be distinctly understood that a sharp line of demarcation cannot always be laid down between the fusible and the infusible varieties. As a result of experience gained during the course of several dozens of preparations, it has been found that even under exactly similar conditions the a-variety often turns out to be largely admixed with the P-variety ; but the evidence of the formation of the latter in the pure state has been unmistakable.It is to be hoped that further light will be thrown on the constitu- tion of silver nitrite by the determination of specific gravity, as also by interaction with ethyl iodide. *203. ‘‘ The products of heating silver nitrite.” By Edward Divers. One of the purposes of this paper is to show that R8y and Gafiguli, in the course of their interesting work on the effects of heating silver nitrite, have met with nothing which supports the belief that there are two chemical varieties of that salt. The other purpose of the paper is to endeavour to increase the confidence in the accuracy of their important experimental resuits, which are hardly in accordance with current views concerning the oxides of nitrogen.Accounts of experiments on the effects of heating silver nitrite already published will be found in the following publications (Trans., 1871, 24, 85 ;Proc. Roy. SOC.,1871, 19, 429 ;and Tv*ans.,1885, 47, 634; and 1899, 75, 111). Precipitated and washed silver nitrite seems always to give some nitrate when heated, but, according to RAy and Gaiiguli, fractional recrystallisation of the precipitated salt, effected by dissolving it in hot water and slowly cooling, gives as the last fraction crystals which may be so heated as to decompose without yielding any nitrate at all. The term fractional crystallisation is here used as appropriate, because the authors state that the salt before recrystallising often behaves as though it were a mixture of its two forms, that which does not give nitrate and that which does, although on what grounds it is dificult to understand.They seem to have with lead nitrate under conditions exactly similar to the above were made, the only difference being that the substance was heated to a ninch higher temperature. The mean of three experiments gave the percentage of nitrogen as nitrate = 4-21, as nitrite =4‘21, whilst the percentage of oxygen was 4,6. According to the equation Pb(NO,), = PbO +ZNO, i-0, these proporlions should be N =8.48 and 0=4‘84. Hence it is clearly established thnt nitric peroxide, even when mixed with oxygen, in reacting on an alkali, yields the nitrate and nitrite in equal amount, the oxygen passing off unabsorbed. A trace of a higher oxide of lead which is found in the intermediate stage in the residue appears from its colour to be red lead (compare Divers, Trans., 1899, 75, 84).These experiments also prove the trustworthiness of the method employed. 282 made no inspection of the precipitated salt under the lens, in order to seek for two forms of crystals. No distinction can be made as regards any essential difference between ii a mealy crystalline powder ” and “slender needles,” since the former is only the result of hasty crystallisation during precipitation, and the latter are only obtained by slow crystallisation. The former variety of the salt, we are told, fused when heated at 220’ and above; the latter variety did not in the least fuse. This statement cannot, however, be accepted as evidence, since silver nitrite does not fuse, but decomposes freely at about 180°, and will do so quickly and completely at that temperature without any fusion of its products of decomposition taking place.What does fuse in the decomposition of silver nitrite at 220--250° is any silver nitrate produced, this salt melting below 217”. The remaining difference observed in the nature of the decomposi- tion products of the two forms of silver nitrite supplies, however, no grounds whatever for stating, as RAy and Gafigizli have done, that the essential or primary decomposition is into silver and nitric peroxide in the one case, and into silver, nitric oxide, and oxygen in the other, since in this instance the one volume of oxygen and the two of nitric oxide will soon become nitric peroxide also.All that these authors can look to as marking the distinction which they believe to exist, is that they get, exclusive of products common to the two cases, some nitrate and some residual nitric oxide in the one case, whilst in the other, under the same conditions of procedure, they get paler gases and can isolate from them a little oxygen. There is not much difficulty in finding a sufficient reason for this difference of behaviour in the different way in which the salt will pack itself in the tube in the two cases. When the salt is heated in the state of powder the resulting gases will be temporarily imprisoned in the interstices OC the mass and the heat will penetrate it slowly enough to permit of the metallic silver of the already decomposed part being acted on by the gases evolved from the still decomposing parts of the nitrite.In this way nitrate will be formed and the gases made to contain a greater proportion of nitric oxide than would otherwise be the case. If, too, it be assumed that the gases are primarily oxygen and nitric oxide, their detention in the residual mass will give time for their union, more or less, into nitric peroxide and thus account for the redder colour of the resulting gases. On the other hand, when the nitrite is in the form of slender needles, the slight contact of the needles with each other and with the walls of the tube, together with their open arrangement in the tube, will cause the whole mass of the salt to be decomposed so quickly and so nearly simultaneously by the heat suddenly radiated on it from the malls of the heating chamber employed, that, with the vacuum maintained, there will be no temporary detention 283 of the gases by the solids, and no time, therefore, for secondary actions to take place, Not even the production of much nitric peroxide by the union of the oxygen with the lower oxide of nitrogen should be possible before the gases have reached the potassium hydroxide solution.Rky and GaEguli attempt to strengthen their position that there are two constitutionally different silver nitrites by claiming that, in con- junction with Sen, one of them has shown already (Trans., 1903, 83, 49 1) that the decomposition of meimwous nitrite by heat indicates that this salt also has a twofold constitution. They make no reference, however, to the fact that the present writer denied at the time (PYoc., 1903, 19,78) that they had sufficient grounds for maintaining that view.Much mercurous nitrate mas formed in their experiments, along with a very little red oxide, and to the production of this oxide they attached special significance, unmindful of the familar fact that mercurous nitrate itself readily yields mercuric oxide when moderately heated. Naturally some scepticism will be felt as to the correctness of R$y and Gaiiguli’s implication that oxygen and nitric oxide, mixed in the proportion to form nitric peroxide, can remain for any observable time without passing wholly into combination as that compound.Quite recently, however, any ground for that scepticism has been largely, if not wholly, removed. Raschig (Zeit. angew. Chem., 1905, 18,1281)has just shown by convincing experiments that the two gases take only R small, although measurable, fraction of a second to combine to the extent necessary to form, what must be taken to be, nitrous anhydride, thus :(x+1)0, +4N0 =x0, +2N,O,, and that the anhydride then very milch more slowly oxidises into nitric peroxide. No difficulty, therefore, need be felt in accepting RBy and Gnfiguli’s results and in believing that in their experiments there was such an outburst of gases from the decomposing silver ni trite-rapidly and uniformly heated in a vacuum to a temperature much above its decomposing point-as to cause the gases to travel 5 cm., or whatever was the distance, to reach the potassium hydroxide solution in a fraction of a second short enough to save some of the oxygen from passing into combination as nitric per- oxide.If this be felt to be the case, it will be seen that RAy and Gafiguli have indeed done excellent work in their indirect confirma- tion of Raschig’s remarkable discovery of the slow formation of nitric.*peroxide. R&y and Gaiiguli’s results being accepted, it must be concluded that when silver nitrite is heated, it always decomposes primarily into silver, nitric oxide, and oxygen, and not that, as these chemists assume, it sometimes also decomposes into silver and nitric peroxide.It has still to be considered how the decomposition must proceed in order that oxygen and nitric oxide may be liberated together. These authors 284 merely suggest that the salt decomposes in the way indicated by the dots in the formula, Ag*O*NO,which, put in that way, does not assist one much. The only explanation apparently possible is that, just as silver nitrate decomposes when heated into oxygen and nitrite, so will the nitrite, in its turn, decompose or tend to decompose into oxygen and hyponitrite, the latter substance almost simultaneously becoming silver and nitric oxide. In support of the possibility of such a change, there is the fact, recorded by the present author (Proc.Bop. SOC.,1871, 19,429), that silver nitrite, when decomposed by heat, on one occasion left a minute quantity of a bright yellow silver compound, apparently hyponitrite, which was insoluble in water and soluble in ammonia. As, however, this substance was not again obtained (Trans.,1899, 75, lll), it is uncertain whether it was really hyponitrite. DISCUSSION. The PRESIDENTexpressed regret that Dr. Divers had found it necessary to express dissent from the conclusions of the authors of the preceding communication, inasmuch as the salts corresponding to the tautomeric forms of nitrous acid had long been sought for.. He was of opinion that no method of determining the constitution of these salts based on the study of their products of decomposition by heat was likely to lead to satisfactory results.He considered that it was by the application of organic reagents in solution, such as the alkyl iodides, that more decisive information was likely to be obtained, and mas somewhat surprised that the authors had not made this next comparatively simple step in order to test the accuracy of their conclusions. “204. ‘‘A contribution to the chemistry of benzoic sulphinide.” By Frederick Daniel Chattaway. In continuation of the author’s work on the sulphonamides, the action of chlorine on benzoic sulphinide (saccharin) has been investigated. When chlorine is passed into a solution of saccharin in aqueous potassium or sodium hydroxide, a sparingly soluble solid substituted nitrogen chloride may be precipitated, or the solution may remain clear according as an equivalent quantity of caustic alkali or an excess has been used.In the latter case, on the addition of a mineral acid, a compound is precipitated which may be a sulphondichloroamido-or a sulphonmonochloroamido-acid, according as the chlorine has or has not been added in excess. When chlorine is passed into a solution of the sodium salt of saccharin, o-benzoic N-chlorosulphinide or chloro- 285 iminosaccharin is precipitated in accordance with the following eauation : C,H4<co>NC1 + NaCl.so2 This readily dissolves in an excess of caustic alkali, forming a salt of o-sulphonchloroamidobenzoic acid, thus : C6H,<Co>NG1 + 2KOH = C0,K*CGH4*S0,(OK):NCl+H20;so, the latter, when treated with an excess of chlorine, is converted into the corresponding salt OF o-sulphondichloroamidobenzoic acid, thus : CO,K*CGH,*SO,(OK):NCl+ C1, = CO,K*C,H,*SO,*NCI, + KCl.Both of the acids can be liberated from their salts as sparingly soluble crystalline solids on addition of dilute mineral acids. "205, '(The action of heat on a-hydroxycarboxylic acids. Part 11. a-Hydroxgmargaric acid, a-hydroxypalmitic acid, a-hydroxy- pentadecylic acid, and a-hydroxymyristic acid." By Henry Rondel Le Sueur, When the a-hydroxy-derivatives of margaric, palmitic, pentadecylic, and myristic acids are heated to 270-5275', they decompose with formation of the lactide of the hydroxy-acid and an aldehyde con-taining one carbon atom less than the original hydroxy-acid, the yield of aldehyde varying between 35 and 50 per cent.of that required by theory. This decomposition is exactly analogous to that undergone by a-hydroxystearic acid when it is heated (TTc~s.,1904, 85, 827), and may be represented thus : R*CH(OH)*CO,H--+ RCHO + HC0,H -+ CO + H,O. 2Et*CH(OH)*CO,H 4RoYH*O*VO OC-0-CH*R' The aldehydes, which are white solids, readily soluble in the ordinary organic solvents, possess all the properties characteristic of aliphatic aldehydes, that is, they form oximes, semicarbazones, hydroxycyanides, and yield the corresponding acids on oxidation with potassium permanganat e. As the yield of aldehyde is a good one, this method is especially applicable to the preparation of these compounds and also for passing from one acid to the next lower member in the same series.286 *206. “Studies on optically active carbimides. Part 11. The reactions between Z-menthylcarbimide and alcohols.” By Robert Howson Pickard, William Oswald Littlebury, and Allen Neville. I-Menthylcarbimide reacts readily with alcohols, and fourteen have been shown to yield I-menthylcarbamates, the molecular rotations of the same having an approximately constant value for each solvent. The course of a reaction between the carbimide and an alcohol can be readily followed in the polarimeter. The reaction between ethyl alcohol and the carbimide is bimolecular, the velocity being greatly influenced by the solvent used.When ethyl alcohol is employed as the solvent, the reaction becomes unimoleculnr, and the velocity constant is approximately proportional to the change of temperature. The velocity constants of the reactions between the carbimide and fourteen alcohols are compared, “207. “ The liberation of tyrosine during tryptic proteolysis. P A preliminary communication.” By Adrian John Brown and Edmund Theodore Millar. A method of directly estimating tyrosine by bromination recently described by James €€.Millar (Trans. Guinness Research Laborcctoi*y, 1903, Vol. I, Part I) appeared likely to furnish a means of measuring the activity of proteolytic change in those cases iu which tyrosine is liberated during the breaking down of the protein molecule.An investigation in this direction.was therefore commenced by the authors and the following is a summary of the results so far obtained. (1) J. H. Millar’s method of estimating tyrosine by bromination is applicable to the estimation of tyrosine in the presence of proteins and their earlier cleavage products due to enzyme action if suitable, control experiments are employed. (2) Tyrosine is not a late product of tryptic protoolysis, as is usually supposed; on the contrary, the tyrosine nucleus of a protein is attacked, and the whole of the tyrosine liberated during the first stage of tryptic digestion. (3) The resistance of the protein tyrosine nucleus to peptic hydro- lysis is confirmed. (4)Attention is called to the similarity of Emil Fischer and E.Abderhalden’s recent observations on the actions of tryptic and peptic enzymes on polypeptides containing a tyrosine nucleus (Zed. physiol. Chem, 1905, 46, 52) to the authors’ observations on the actions of the same enzymes on proteins containing a tyrosine nucleus. 287 (5) The authors' investigations appear to indicate a trustworthy means of differentiating enzymes of a peptic from those of a tryptic nature, and may assist in throwing some light on the confused state of knowledge with regard to the existence of a tyrosine nucleus in the different albumoses resulting from peptic and tryptic proteolysis. 208. Ethyl piperonglacetate." By William Henry Perkin, jun., and Robert Robinson. When piperonylic acid, CH20,:C6H,*CO2H, is treated with phos- phorus pentachloride, it is converted into piperon91 chloride, CH,O,:C,H,*COCl, a colourless, crystalline substance which melts at 80" and distils at 155" (25 mm.).This acid chloride (1 mol.) reacts with the sodium derivative of ethyl acetoacetate (2 mols.) yielding the pale yellow crystalline sodium derivative of ethylpiperonyl-acetoacetate, CH,0,:C,H3*COCNa(CH,*CO)*CO,Et;the corresponding cupric derivative, (C14H1306)2Cu, crystallises from toluene in bluish- green plates. Ethyl piperonylacetoacetcte, obtained from the pure sodium derivative by treatment with acids, is a colourless syrup which is soluble in sodium carbonate and gives a reddish-violet coloration with alcoholic ferric chloride. When the sodium derivative is treated with ammonia and ammonium chloride (Claisen, An.lzccZen, 1896, 291, 70), it is decomposed with formation of ethpl piperonylacetate, CH,O,:C,H,*CO*CK,*CO,Et,a solid, crystalline substance which melts at 41", gives a reddish-violet coloration with ferric chloride, and yields a copper derivative, (C12H1105)2CU'The authors wish to reserve, for a short time, the investigation of these new compounds.209. The action of ultra-violet light on moist and dried mixtures of carbon monoxide and oxygen." By Samuel Chadwick, John Edwin Ramsbottom, and David Leonard Chapman. The chemical effects produced by the passage of the electric dis- charge through gases are the result of at least three distinct causes, namely, (1) the cathode rays, (2) ultra-violet light, (3) catalytic action of the electrode and in particular the cathode.Ultra-violet light alone has been shown by Lenard to act on oxygen with the formation of ozone. The authors working wibh a quartz mercury lamp, with which three per cent. of ozone could be produced from pure oxygen, have obtained the following results. A mixture of equal volumes of carbon monoxide and oxygen dried with sulphuric acid and submitted 288 to the action of ultra-violet light, contracted at first slowly, and then more rapidly, until a maximum rate of decrease of volume was attained, The rate of contraction then gradually decreased, and finally became so slow that the experiment was stopped, and the composition of the gases found by analysis.It was ascertained that 22-95 per cent. of the carbon monoxide had been converted into carbon dioxide, and that 39.63 per cent. of the original oxygen had been changed into ozone. A mixture of equal volumes of carbon monoxide and oxygen dried with phosphoric oxide behaved in almost the same way as the mixture which had been dried with sulphuric acid alone. When the con-traction had reached approximately the same value as in the last experiment, it was found on analysis that 19-42 per cent. of the total carbon monoxide had been converted into carbon dioxide, 37.48 per cent. of the original oxygen being this time changed into ozone. With the same mixture saturated with water vapour at 16O, the result was markedly different. The rate of contraction was practically uniform throughout the experiment, and this rate was less than half the value of the maximum rate with the dried mixture.When the total contraction had reached almost the same value as in the two previous experiments, it was found that 53.2 per cent. of the carbon monoxide had been converted into carbon dioxide, and only 2.6 per cent. of the oxygen into ozone. If the first action of the ultra-violet light is conceived as consisting of R breaking up of the oxygen molecules into atoms, the atoms of oxygen thus formed prefer to combine with the molecules of carbon monoxide when the gases are moist, but with oxygen molecules when the gases are dry. In the present case, the rate of chemical change, measured by the contraction, is not accelerated by the presence of moisture, but the course of the reaction is determined by the hygro- scopic condition of the mixture.210. ‘‘Benzoyl derivatives of salicylamide.” By Arthur Walsh Titherley. Doubt has been thrown by Einhorn and Auwers on the formula BzO*C,H,*C(OH):NH, attributed by Titherley and Hicks (Trans., 1905,87,1207) to the stable benzoylsalicylamide (m. p. 20s’) originally obtained by Gerhardt and Chiozza (Ann. Chim. Phys., 1866,46, 139), and which is produced by rearrangement even at 15O from the labile O-benzoylsalicylamide, BzO*C,H;CO*NH, (m. p. 144*), receutly iso- lated by Titherley and Hicks. Einhorn, in conjunction with Schupp (Bey., 1905,38,2792), and also with Haas (Ber.,1905,38,3628),considers the stable substance to be the 289 X-benzopl derivative, OH*C6H,*CO*NHBz, as also does Auwers (Ber., 1905, 38, 3256), who regards the rearrangement as due to the wandering of the benzoyl group from 0 to N: BzO*CGH,*CO*NH, (labile, m.p. 144’) -+ OH*C6H,*CO*NHBz (stable, m. p. 208’). The change would be analogous to that which takes place when attempts are made to isolate 0-acyl-o-hydroxy-aromatic amines of the type AcO*C6H,*NHR and AcO-C,H,*CH,*NHR, where rearrangement occurs leading to the production of the Y-acyl derivatives. If the N-benzoyl formula be ascribed to the substance (m. p. ZOS’), it must be looked on as possessing anomalous properties; thus, it gives no ferric chloride reaction, is not decomposed by ammonia, like C6H5*CO*NHBz,and in other ways does not behave like an N-benzoyl derivative. Further, on heating with phosphorus oxychloride, it yields benzoylsalicylnitril~, which favours the 0-benzoyl formula, thus : BzO*C,H,-C(OH): SH -3 BzO*C,H;CN + H,O.Further investigations are proceeding with a view to elucidating the correct constitution of the substance. 211. LL The constitution and colour of diazo- and azo-compounds.” By Arthur Hantzsch. In the August number of the Transactions, Armstrong and Robertson published a paper under the title : ‘‘The Significance of Optical Pro-perties as Connoting Structure” (pp. 1272-1297), in which my t.heory of the stereochemistry of the diazo-compounds is criticised, and the remarkable conclusion expressed, that ‘‘ the Hantzsch-Werner hypothesis ” (in reality, so far as concerns the diazo-compounds, the ‘‘ Hantzsch hypothesis ”), ‘‘ besides being an intangible and improb- able conception, is unnecessary in fact.” If such an expression of opinion were correct, it would certainly not, be without some significance, whilst the same holds conversely if such a view is shown to be incorrect, or at all events founded on a false basis.Since the latter is the case, it will be readily admitted that such a refutation ought also to find a place in the Society’s publications. The facts on which I venture to base this statement are simply the various researches on the mbject, which I have published in the pages of the Berichte der deutschen chernischen Gesellschaft, a synopsis of which is to be found in a small published brochure, “Diaxoverbin-clu~zgen,” F.Enke, Stuttgart, 1902. The delay in replying is due to the fact that I only became BC-quainted with Armstrong and Robertson’s work at the beginning of November. 290 Armstrong and Robertson proceed from the assertion that (‘all compounds containing the group Ph*N:N*X must be coloured to the conclusion (p. 1280) that “all compounds of the type Ph*N:N-X should be coloured, and consequently only coloured diazo-compounds can be represented by such a formula. The formulae assigned by Hantzsch to the so-called normal and isodiazotates are at once ruled out of consideration by this argument, as both these classes of corn-pounds are colourless ” ; in other words, the latter do not correspond to the structural formula Ph*N:N*OK. It must first be observed that all chemists from Kekule onwards, who have worked on diazo-compounds, must therefore have employed an incorrect formula, for they all, before as well as after the discovery of diazo-isomerism, accepted the formula Ph*N: NoOK for at least one of the two isornerides.But apart from this, Armstrong and Robertson’s assertion can readily be shown to stand in contradiction to the facts, for according to their views the nature of an azo-compound as such is established by the fact that the compound is a coloured sub- stance, and, conversely, a particular substance cannot be an azo-deriv- ative because it is colourless.Such a conclusion has up to the pre- sent proved totally unacceptable, For Thiele’s well-known extensive researches (Annalen, 1896, 290, 1) have shown that both coloured and colourless axo-conzpounds exist in the aliphatic series, for instance, the deep red azo-dicarboxylic ester, CO,R*N:N*CO,R, and the colourless azo-isobutyric acid derivatives, CRMe,*N :N*CRMe,. When Arm-strong and Robertson proceed “being colourless, the diazo-salts cannot be formulated as diazene (-N:N-) compounds” (p. 1280), it is cer-tainly logical to assert ‘‘that being colourless these so-called azo-compounds of the aliphatic series cannot be compounds of the type -C N N C.” So long, therefore, as Armstrong and Robertson do not offer any explanation of these facts, or substitute other constitutional formulae for these colourless compounds, regarded generally as azo- derivatives, just so long will their conclusion, namely, ‘‘that diazo- tates being colourless cannot have the ordinary formula Ph*N:N*OK,” remain unacceptable. But amongst the diazobenzene derivatives there also exist true chemical compounds containing the group Ph*N:N*X;these, therefore, accordirig to Armstrong and Robertson, must be coloured, but in reality they are colourless. For example, amongst the nitro-isodiazobenzene esters we have the nitro-diazo-ester, NO2*CGK,*N:N*O*CH,(von Pechmann, Bey,, 1894, 27, 672), which, to quote the author’s descriptiou, “in the pure state is perfectly colourless.” Here again it is necessary for them to replace the formula by a more suitable one, or their conclusions must necessarily be regarded as incorrect.291 According to their view, “ the normal diazotates must perforce be regarded as diaxonium derivatives ” ; I do not consider it necessary to disprove this statement, and will content myself by pointing out that even Bamberger has given up the diazonium formula for the labile diazotates (Annalen, 1900, 313, SS), and that his last attempt to rehabilitate it (Ber.,1903,38,4054) has been shown to be unwarranted (Ber., 1904, 3’7,1084). As regards the proposed formulze for the isodiazotates (p. 1282), Ph*N-N*K or Ph*NK*NO,the same remarks apply. I discussed \/0 these formulze at length some considerable time ago, and showed them to be unsatisfactory, and they have, as a matter of fact, been abandoned by all chemists who have studied experimentally the chemical behaviour of these substances.The two formulze of Armstrong and Robertson also stand in contradiction to the fact that the previously-mentioned diazo-ester, NO;C,H;N:NoOCH,, can be obtained from the isodiazotate, so that in consequence the existence of a third hydroxyl form must be accepted. These hydroxyl com-pounds (Ph.N:N*OH) are not imaginary tautomeric substances, but real, definite, chemical compounds, for in conjunction with W. Pohl (Ber., 1902, 35, 2964) I have shown that from the colourless isodiazo- tates there is formed, primarily, the free iso-(anti)diazohydroxide as a colourless, true acid, the general behaviour of which certainly indicates the presence of an (OH) group.Armstrong and Robertson must therefore suggest another ‘‘hydroxyl formula” in place of Ph*N:N*OH, and the fact cannot be too plainly pointed out that in accepting the nitrosoamine formula for the iso- diazotates they again immediately stand in contradiction to their funda- mental doctrine on the relation of colour to constitution, for, as is well known, most of the true secondary nitrosoamines, and nitrosoamine derivatives, are coloured. The indifferent primary nitrosoamines obtained as pseudo-acids by W. Pohl and myself through intramolecular change of the diazohydroxides are also coloured, although as a logical consequence from Armstrong and Robertson’s nitrosoamine formula (that is, absence of the group Ph*N:N) these isodiazotates should be colourless if they were really nitrosoamine salts.As is seen from the three formuh : 1. 2. 3. by simple substitution of K for H or R, we obtain from the coloured substances (1)and (2) a colourless potassium salt (3), a result 292 which is again incompatible with Armstrong and Robertson's theory." The whole of Armstrong and Robertson's views on the normal diazosulphonates and diazocyanides are quite incorrect. They state (p. 1281) " the action of sulphitc may be supposed to involve in the first place the formation of a diazonium eulphonate, R*N*So,K,P and, 9s so far as I can understand, also put forward the formula Ph*NH*SO,K*NOH. The latter formula is impossible, because most diazosulphonates correspond to the formula Ph*N,*SO,K ; that is, to one,containing no water.The diazonium formula itself stands in contradiction to their theory, for if the appearance of colour denotes a change in constitution,and if all the sulphonates of colourless metals (namely, those of silver and mercury) are colourless, why is it that the diazonium sulphonates formed from the colourless diazonium and sulphonic acid components possess an intense orange colour 1 From the very fact that the labile equally with the stable sulphonates are coloured, they must both be azo-compounds, Ph*N: N*SO,K. The statement that " the so-called syn-compound sulphonates and cyanides may well be simple equilibrated mixtures of diazonium cyanides and sulphonates with the stable anti-compounds " (p.1283) is controverted by the facts, for all the normal diazocyanides exhibit analogous behaviour with water and cuprous oxide, but in a manner quite different fram that of the isodiazocynnides. Further, as regards their colour and constitution, the labile syn-diazocyanides and diazo- sulphonates are always more intensely coloured than the stable ad-forms. All diazonium sulphonates are colourless, and all diazosul- phonates should be colourless ; so that Armstrong and Robertson's view leads to the remarkable result that, by the addition of a colourless to a coloured substance, the colour intensity of the resulting mixture is increased-certainly the greatest contradictio in adjecto.In addition, Armstrong and Robertson have not sufficiently taken into considera- tion the fact that the labile cyanides are distinct chemical compounds possessing definite unchangeable properties, that is, they are not chemical mixtures. The explanation of the change of the syrz-into the anti-form (p. 1281) is impossible by reason of the assumption that an addition of the elements of water takes place, with a subsequent * The reference to Dobbie aiid Tinkler's work (Tyans., 1905, 85, 277 ; and Proc., 1905, 21, 75), namely, "that the salt NO,'C,H,*N,'OK, in respect to its absorption spGctrum, behaves as a nitrosoarnine, and not as a diazo-salt," stands in marked con- tradiction to all its chemical properties.This being so, too much weight cannot be attached to this evidence until it has been ascertained, for example, how the isomeric esters N0,*C,H4N:N'O'CH, and NO;C,H,K( CH,)*NO behave under similar con- ditions, a point which the above-named chemists, at my request, have niost kindly promised to investigate. splitting off of the same elements, for in reality many syn-sulphonates and very many sgn-cyanides isomerise in the solid state or in anhydr- ous solvents. In short, therefore, the whole of Armstrong and Robertson’s con-ceptions with respect to labile diazo-isomerism are impossible, and their remark that my “syn-anti-conception is based upon a false use of the principle of analogy ’’ will certainly be considered as more applicable to their own untenable theories, according to which “ the stereochemistry of the diazo-compounds is unnecessary in fact.” With such statements as ‘‘in the case of the diazosulphonates, it is clear that they differ essentially in type,” put forward without the support of a single experimental fact, equally without any theoretical explanation, discussion is out of the question and, in fact, would be superfluous.It is unfortunately nezessarg for me to make an emphatic protest in reference to Armstrong and Robertson’s remarks (p. 1280) on the small value which ought to be placed on the analytical results of the labile diazo-isomerides. One has the right to expect that before such statements are made reflecting on the accuracy of the work in question, the greatest care has been taken to verify the facts.That such a sweeping assertion is altogether unwarranted, will, I think, be admitted from a consideration of the following points : (1) Labile Dinxotates.-The labile diazotates certainly always contain small quantities of alkali (Ber., 1901, 34,2159 ; 1902, 35, 2969) or water of crystallisation (Bey., 1895, 28, 2006; 1896, 29,1077), but in the form of their crystalline salts they have been obtained quite pure, so that no chemist who has worked on the subject, from Kekule on-wards to Bamberger, has ever seriously questioned the accuracy of the empirical formula ArN,OK for the diazotates. (2) Labile DinxosuZp1ionates.-The numerous concordant analyses on these substances (Ber., 1894, 27, 3529; 1897, 30, 76, 80-81) prove undoubtedly the accuracy of the formula PhN,SU,K for this substance.It is true there is generally present a small quantity of the anti-salt, formed by spontaneous isomerism of the syrz-derivative, but this certainly does not come into question as affecting the accuracy of the formula or as regards the facts of the isomerism. (3) LabiEe Biccxocyanides.-The fact must be emphasised that many of these compounds can without difficulty be very readily obtained and isolated in a pure state (Ber., 1896, 29, 666 ; 1897, 30,2530), so that their constitution as chemically individual substances cannot be doubted. They are not to be regarded, therefore, as ‘‘ eminently unstable ” and “impure,” as Armstrong and Robertson assert.As a matter of fact, some of the syn-derivatives are so stable as to be only convertible with difficulty into the more stable isomeric anti-form. The undoubted existence of these two classes of compounds (the representatives of the stereo-isomeric azo-compounds), which Armstrong and Robertson do not admit, provides therefore the strongest proof for my stereochemical theory of the diazo-derivatives, a theory supported by a large mass of experimental evidence, in connection with which the theoretical signification has always been carefully pointed out. The reflection by Armstrong and Robertson on the accuracy of this work is altogether unwarranted, and with a thorough knowledge of the subject, it is impossible for me to understand how such assertions could be made.I am forced to conclude that they have not thoroughly informed themselves in respect to my experimental investigations. Above all, I have to deplore that the numerous exact analytical results already published should thus be brought into discredit, and the stereo-chemistry of the diazo-derivatives founded on them regarded as “unnecessary in fact”; to be replaced by a view with which the facts, indeed the principle itself, stand in direct contradiction. In reply to the statement that “I am opposed in principle to conclusions based on optical evidence” (Bey., 1899, 32, 3149), it is only necessary for me to say that such conclusions in regard to constitution are not warranted from a mere consideration of the optical properties, more especially when these stand in contradiction to the general chemical behaviour of the substance. It is certainly a very great surprise to me that such a statement should be brought forward, for I have always regarded the physico- chemical behaviour of the substance as of very great importance, and especially in relation to the colour of substances as denoting their constitution.Thus, some eighteen years ago, in conjunction with Hermann (Be?.., 1887, 20, 280l), I was one of the first to draw attention to the relation between colour and constitution in the case oE desmotropic substances, and recently, as a result of my researches on pseudo-acids, I have been able to show experimentally that the appearance of colour in the formation of coloured alkali salts from hydrogen compounds is due to an intramolecular change taking place in the position of a hydrogen atom.I intend publishing shortly an account of several researches dealing with the relation of colour to constitution, and in particular establishing the quinonoid structure for nitrophenols, a theory first put forward by Armstrong on very slender experimental evidence, and certainly not accepted by a large number of chemists at the present time. Summarising, it is my firm conviction that the colour of substances is one of the most important criteria in the characterisation of their constitution, but at the same time it is also one of the most delicate and subtle.Unfortunately, it is in so very many cases quite im- 295 possible to explain the origin of the colour, or to account for the remarkable phenomena by structural formula It is only necessary t'o recall the existence of the coloured fulvene, of the coloured diphenylene-ethylene derivatives (y6H4>C:L'R,) on the one hand, C,H, and the colourless polyacetylene on the other ; of the coloured derivatives of diet hoxynapht host ilbene, di benzoylet hylene, and benzal- desoxybenzoin compared with their colourless isomeric modifications. In short, as pertaining in particular to the azo- and diazo-derivatives considered in the light of their chemical and physical properties, there exist both coloured and colourless azo- and diazo-compounds, the cause of which colour is unknown, and which, although representable by Baeyer's valency formuh (-Ph*N:NR colourless, Ph*NxN*R coloured), remain still unexplained by any rational structural formule Above all it should not be overlooked that a sharp line of demarcation between coloured and colourless substances does not exist either theoretically or practically; for the same complex appears in an intensely-coloured, a pale-coloured, or a colourless substance, according to the nature of the groups associated with it.Thus, in the case of the aromatic azo-complex Ph*N:N, when this is attached to nitrogen the colour-intensity of the products is less than when it is attached to carbon (thus, Ph*N:N*NH*C,H, possesses a lighter yellow colour than Ph*N:N.CN or Yh*N:N*Ph). It is therefore comprehensible that when the same complex is attached to oxygen (as in the diazotates Ph*N:N*OR) we have a colourless substance formed, more especially as the diazo-compounds containing the group RO*N:N*OR (for example, hyponitrous acid, salts, and esters) are also colourless.We have accordingly in the following series of colour intensities : Ph*N:N*OR Ph*N:N*NHR Ph*N:N.CN Colourless. Pale-coloured. Intensely-coloured. a collection of facts which we cannot explain or represent satisfactorily by structural formulze. The change of condition from the coloured to the colourless state in szo-compounds is bound up with, but not, however, altogether dependent on, the known structural and stereochemical isomerism of the diazo-derivative, that is, presence or absence of colour is not definitely decided by such isomerism, for whilst both classes of the stereoisomeric diazotates are colourless, both those of the stereo-isomeric diazosulphonates and diazocyanides are coloured.Since Armstrong and Robertson's views and formulae are quite untenable, the older structural and stereochemical formuh indicate now, as before, the best and most accurate representation of the facts con-cerning the diazo-compounds. 212. ‘6 Note on the incandescent mantle as a catalyst and its applica-tion to gas analysis.” By John Ernest Mason and John Wilson. The method described by Lewes (Chem. News, 1905, 91, 61) for demonstrating the incandescence of the ordinary gas mantle in a cold mixture of coal gas and air may also be employed with a mixture of ammonia vapour and air. The authors described a modification for showing the incandescence of the mantle in an unburnt mixture of alcohol vapour and air.Although less effective, the mantle may be used as a substitute for platinised asbestos in the ordinary lecture experiments for preparing formaldehyde from methyl alcohol vapour and air, and sulphur trioxide from sulphur dioxide and oxygen. Fragments of mantle in a hard glass or preferably quartz tube may be used in place of palladium or palladium-asbestos, for the estimation of hydrogen and carbon monoxide in gas analysis by com- bustion with excess of air or oxygen. Methane and mixtures of methane and hydrogen may be estimated similarly by passing these gases mixed with excess of oxygen over fragments of mantle heated in a quartz tube, and measuring the contraction after combustion and subsequent treatment with caustic potash solution.The results agree well with those obtained by the customary explosion methods. Good results may also be obtained by passing the gases mixed with oxygen over asbestos heated in a Emall quartz tube. Hydrogen, and less readily methane, may be estimated by passing the gas mixed with oxygen through narrow tubes of heated Jena glass alone. 213. The influence of certain amphoteric electrolytes on amylolytic action.” By John Simpson Ford and John Monteath Guthrie. An investigation of the influence of asparagine, glycine, and a-alanine on amylolytic action has led to the following conclusions : (1) Asparagine and the amino-acids mentioned have no specific influence in augmenting the action of amylase j the apparent augmen- tation of action sometimes obtained by the addition of these ampho- teric substances (or of feeble acids) is due to their neutralising alkaline (or other) impurity in the starch or enzyme solution.(2) Normal amylolytic action takes place in neutral solution. In the plant substance, this neutrality is brought about by equilibrium be- tween the basic and acid products present. (3) Until the conditions influencing the action of enzymes are more fully established, it is inadvisable to formulate mathematical laws as to the kinetics of enzymic hydrolyses.297 (4) Purified soluble starch has the properties of an extremely feeble acid; it is capable of yielding negative ions under the infirience of strongly positive ones. 214. (( The estimation of picric acid additive compounds.” By Prank Sturdy Sinnatt. The method of Knecht and Hibbert (Bey., 1903, 36,1549) for the estimation of picric acid by means of titanous ch1oi;ide has been found to be applicable to other picrates, and also to picric acid additive compounds. Twenty-five C.C. of a solution of 0.200 gram of naphthalene picrate in 250 C.C. of alcohol were titrated with titanous chloride, and gave 99.49 per cent. of naphthalene picrate, Pgridine and strychnine picrates yielded 100.19 and 99.69 per cent.respectively. In many cases it is convenient to dissolve the picrate in hydro- chloric acid. The method has been applied to the estimation of naphthalene in coal gas ; the naphthalene picrate is separated by the usual process (Colman and Smith, J. Soc. Chem. Ind., 1900, 19, 12S), mashed, dissolved in a small volume of alcohol, and titrated with titanous chloride. If a standard solution of picric acid is used in the mash-bottles, the filtrate and washings may also be titrated. The results compare with those obtained by Colman and Smith’s method. The estimation of naphthalene and the applications of the titanous chloride process to other picric acid additive compounds are being continued, and the results will be embodied in a further communica- tion, 215.Silver dioxide and silver peroxynitrate.” By Edwin Roy Watson. A black, crystalline product, obtained at the anode during the electrolysis of an aqueous silver nitrate solution, was considered by Xitter to be silver dioxide, Ag,O, (Gelden’s Neues J.,1804, 3, 561). Later investigations showed that it could not be regarded as silver dioxide, and a variety of conflicting formulae have been proposed. The author has electrolysed aqueous silver nitrate with different current strengths and densities and with solutions of varying con- centrations, and has analysed the product formed at the mode in order to see whether this should be regarded as a definite chemical compound or as a mixture, the composition of which varies with different conditions.It mas concluded that the product was a definite chemical compound, and that its composition mas correctly represented by S3c’s empirical formula Ag,O,,N. The substance is easily decom- 298 posed by heat or when left in contact with water or organic matter, such as filter-paper, and to t'his cause must be attributed the diver- gent results of the earlier investigators. This compound, silver peroxynitrate, as it has been termed by Tanatar, on boiling with water deconiposes in accordance with the equation Ag,O,,N = AgNO, + 3Ag,02 + 0,. Silver dioxide is a greyish-black powder (sp. gr. 7-44),which may be heated to 100" without decomposition. At higher temperatures it gently decomposes into its elements.It dissolves in hot dilute sul- phuric acid in accordance with the equation 2Ag202+ H,SO, = 2 A g2S04+ 2H,O + 0,. Its behaviour with ammonia is noteworthy, and may be represented in the following manner : 6Ag,02 + 2NH, = 3Ag40, + N, + 3H,O, so that the compound in solution must be regarded as a polyvalent silver compound, probably mAg40s,nNH3. The dioxide of silver and silver peroxynitrate both dissolve in cold concentrated nitric acid with the production of an intensely brown solution, the colour of which gradually fades even at the ordinary temperature and niuch more rapidly on warming. The rate of decom-position of the cornpound is proportional to its concentration in the solution, a fact which makes it impossible to give to the compound the simple formula &(NO,),. The formula Ag,(NO,), and Ag,(N04), are, however, possible.216. bL The constitution of 0-hydroxyazo-compounds. Preparation of benzeneazodimethylcoumarin." By John Theodore Hewitt and Herbert Victor Mitchell. The authors have hydrolysed the 4 : 6-dimethylcoumarin described by Pechmann and Cohen (Bey., 1884, 17, ZllS), and have coupled the alkaline coumarinnte so obtained with phenyldiazonium chloride and the three nitrophenyldiazonium salts. The alkaline azocoumarinates so obtained are highly colourecl, vary-ing in shade from red to violet. On acidification, light-coloured c:Me nnli) dricles of t<he type CH,//\/~HI are precipitated. \,/ \ /' C0 C,H,*N2 0 This instantaneous dehydration indicates the existence of a ready-formed hydroxyl group, even in the o-hydroxyazo-series.Benzeneazo-4 : 6-dimethylcoumarin melts at 199-200' ; the 0-, m-, and p-nitrobenzeneazo-4 : 6-dimethylcoumarius melt at 240-250' (with decomposition), 212", and 2'29' respectively, these melting points being corrected. 217. ‘‘Caro’s permonosulphuric acid.” By Thomas Slater Price. Hitherto it has not been possible to decide between the formulz H,SO, and H,S,O, for Caro’s permonosulphuric acid. The decision could readily be made if a pure salt: for example, the potassium snlt, could be obtained. The simplest method would be to heat a weighed quantity of the salt and determine the weight of potassium sulphate left ; this weight would depend on whether the formula was KHSO, or K,B,O,.The author has not yet succeeded in preparing the pure potassium salt, but a mixture has been obtained containing the potassium salts of sulphuric, permonosulphuric, and perdisulphuric acids, and also potassium hydrogen sulphate. It mas found possible to determine the amounts of each of the constituents present, and thus calculate the weight of potassium sulphate which would be left on heating up a known weight of the mixture; this could then be compared with the actual weight found. The results obtained point to the formula H,S05 as the correct one. ADDITIONS TO THE LIBRARY. I. Doizations. Alsina, Fernando. Nouvelles orientations scientifiques. Ouvrage traduit du Catalan par J. Pin y Soler. pp. 165.ill. Paris 1905. (Red 4/12/05.) From the Author. Bagshaw, Walter. Elementary photo-microgrsphy. pp. 68. ill. London 1902. (Recd. 22/11/05.) From the Author. Board of Agricultare. Report on the results of investigations into Cheddar cheese-making, carried out on behalf of the Bath and West and Southern Counties Society in the years 1891 -98, by F. J. Lloyd. pp. 251. ill. London 1899. (Recd. 23/11/05.) From F, J. Lloyd, Esq, -Report on the results of investigations into cider-making, carried out on behalf of the Bath and West and Southern Counties Society in the years 1893-1902, by F. J. Lloyd. gp. xii + 145. ill. London 1903. (Recd. 22/11/05.) From F.J.Lloyd, Esq. Chapman, Alfred C., and others. The hop and its Constituents. A monograph on the hop plant.pp. 99. ill. (Red 30/11/05.) From A. C. Chapman, Esq. 300 Roscoe, Sir Henry Enfield, and Schorlemmer, Carl. A treatise on chemistry. Vol. I. The non-metallic elements. New edition, corn- pletely revised by Sir H. E. Roscoe, assisted by H. G. Colman and A. Harden. pp. xii + 931. ill. London 1905. (Reference.) From Sir Henry Enfield Roscoe, Society of Arts. Report of the Committee on leather for book-binding. Edited by The Rt. Hon. Viscount Cobham and Sir Henry Trueman Wood. pp. 120. ill. London 1905. (Recd. 30/11/05.) From the Society of Arts. 11. By Purchase. Baume, Antoine. Chymie expbrimentale et raisonnke. 3 volumes. pp. clxt-482, 671, 704. ill. Paris 1773. (Recd. 18/11/05.) Cain, John Cannell, and Thorpe, Jocelyn Field.The synthetic dyestuffs and the intermediate products from which they are derived. pp. xiv + 405. ill. London 1905. (Recd. 23/11/05.) At the next Ordinary Meeting, on Thursday, December 21st, 1905, at 8.30 p.m., the following papers will be communicated : “The relation of position isomerism to optical activity. Part V. The rotation of the menthyl esters of the isomeric dibromobenzoic acids.” By J. B. Cohen and I. H. Zort,man. ‘6 Azo-derivatives from a-naphthomethylcoumarin.” By J.T. Hewitt and H. V. Mitchell. ‘‘The supposed identity of dihydrolaurolene and of dihydroiso-laurolene with 1: 1-dimethylhexahydrobenzene.” By A. W. Crossley and N. Renouf. “The slow combustion of carbon disulphide.” By N. Smith. ‘‘The diazo-derivatives of 1:5-and 1:8-benzenesulphonylnapht hylene- diamines.” By Q. T. Morgan and F. M. G. Micklethwait. P,. CLAY AND GUNS, LTD., BREAD ST. HILL, E.C., AND RUNGAY, SI.FPU1.K.
ISSN:0369-8718
DOI:10.1039/PL9052100277
出版商:RSC
年代:1905
数据来源: RSC
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