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Proceedings of the Chemical Society, Vol. 9, No. 124 |
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Proceedings of the Chemical Society, London,
Volume 9,
Issue 124,
1893,
Page 117-140
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摘要:
ISSued 1815,’1893. PROCEEDINGS OF THE CHEMICAL SOCIETY. No.124. Session 1893-94. May 4th, 1893. Dr. Armstrong, President, in the Chair. Certificates were read for the first time in favour of Messrs. John Bateman, Saltney, near Chester; Robert S. Cahill, 90: Park Lane, Norwich ; Alexander Mitchell Martin, Douglas Villa, Duubeth Road, Coatbridge ; Charles Alexander McKerrow, 41, Eccles 31d Road, Pendletoa, Manchester ; William Itidgely Orndorfi, Ithaca, N.Y., U.S.A.; Wilfred Sessions, Russell House, Gloucester ; Frank Ernest Thompson, 97, Murdock Road, Handsworth, Birmingham. In answer to a question put by -Mr. Cassal, the President expressed the opinion that to read the certificates of sonre, without rending those of all, candidates would be to make an invidious distiiiction, arid that therefore, if such a request were made, he should rule that it was out of order.The following candidates were duly elected Fellows of the Society :-John Frederick Briggs, Julian L. Baker, William A. Bone, Laurence Augustus Baine, John Charles Burnham, William I-tobert Burnetf, Joshua Buchannn, Ralph Edward Brown, George Clayton, James Cameron, Harry Williamson Dixon, H. W. Dickinson, Robert Cecil Twle Evans, Thomas Edwards, Alfred Roland Gower, Robert George Grimwood, John Addymau Gardner, Hedley Gordcjn Jones, Hooper Albert Dickirson Jowett, Sorabji Manekji Kaka, Edrnuiid George Lamb, Herbert Lloyd: Alan E. Munbp, Heury John Monsou, John Alan Murray, J. Jhnk McQregorj, 9B., A.M., James Uason, RaffaBllo Nnsini, William Henry Oates, S.Parrish, Wil liwi ttintoul, James Henry Robbins, George Rudd Thompson, Prank P. Vanden-bergb, B.S., M.D ,A. F. Watson, John Wjlkinson. Of the following papers those marked * were read :-*ll. ''The hydrates of sodium, potassium and lithium hydroxides." ByS. U. Pickering. By cooling solutions of sodium hydroxide the author has succeeded in isolating a large number of hydrates in the solid crystalline con- dition. They considerably outnumber those of which be obtained indications by means of changes of curvature in the case of sulphuric acid-comparing similar ranges of strengths in the two cases-and hen:e TIO improbability can any longer be held to attach to theso latter on account of their being so numerous. The formula of the various hydrates isolated and their freezing points are as follows :-NaOH*h,O ........f. p. 64.3" NaOH*2Hz0.. ...... ,, 12.5 NaOH*3-11H20.... ,, 2-73' Naj0H*3*5Ha0........ 15.55 aNaOH*4Hz0.......... 7.57 f3NaOH*4HzO.......... -1.70 NaOH*5H20.......... -12.22 NaOH*7HzO.......... -23.51 The freezing points or solubility curves of all these hydrates have been followed throughout considerable ranges ; several of them-in one case as many as four-overlap each or'her. As it is scarcely possible to conceive that a crystalline hydrate can be extracted from a solution unless some molecules of that hydrate are present in the solution, this fact must prove that in some cases as many as four, probably even more, different hydrates exist in the same solution.The existence of two different tetrahydrates is noticeable, as also is that of the complex hydrate of the formula NaOH-3t11Hz0 or NaOH*3H20+ NaOH*4H20,which is similar to two of the hydrates of which the author obtained indications in the case of sulphuric acid. Of the eight hydrates, that containing 34 mol. props. of water is the only one which has been previously described. Tn the case of potassium hydroxide; two new hydrates-a mono-and a, tetra-hydrate-have been isolated and examined, in addition to the already known dihydrate. The freezing points of these are KOH-H20.......... f. p. 143" K OH*2H20........... 35.5" KOH.4HZO ........... -32.7 In the case of lithium hydroxide, the already known monohydrate as the only one obtained.119 12. “Detection of arsenic in alkaline solution.” By John Clark, Pb.D. The author shortly reviews the different methods by which arseniuretted hydrogen is generated in an alkaline solution, and finds, as pointed out by Hager, that Fleitmann’s process, which depends on the interaction of finely divided zinc and caustic potash, does not detect arsenic acid, but he is unable to confirm the statement of H. Fresenius, that Gatehouse’s modification of Fleitmann’s test indicates arsenic acid, as he has not been able to volatilise the slightest trace of arsenic by heating arsenate of soda with a large excess of pure aluminium and caustic soda, and he attributes the results obtained by Presenins to the use of impure aluminium, or to the presence of arsenious acid in the arsenic acid.Experiments made to test the applicability of the Gatehouse process in estimating arsenic seem to show that, although it is very delicate and very convenient, it doeg give quantitative results, even when the whole of the arsenic is in the form of arsenious acid. He also finds that arsenic acid in an alkaline solution resists the action of sodium amalgam, and he con- clude2, tbcrefore, that none of the methods which have been pro-posed for the generation of arseniuretted hydrogen in an slkaliue solution detect arsenic acid. 13. “Improvements in Reinsch’s process.” By John Clark, P1i.D. Reinscli’s process, as carried out in the ordinary way, is capable of demonstrating the presence of very minute quantities of arsenic, and, according to Letheby, it withdraws every, and the smallest, trace of arsenic Prom organic mixtures, but there are two objections to its use in medico-legal cases.1st. When the quantity of arsenic is small, a stain is obtained which it is sometimes difficult to identify as arseuic, because the coated copper when heated is apt to give a layer of chloride of’ copper and organic matter, iustead of arsenious acid ;and 2nd. It is not suitable for the quantitative estimation of arsenic, as it is not possible by means of heat to volatilise the whole of the arsenic from the copper. The author’s improvenients consist in identifying the arsenic or antimony on the copper with greater certainty, and at the same time estimating the amount of each when they occur together.For this purpose he digests the coated copper in rz cold mixture of dilute caustic potash and peroxide of hydrogen, which dissolves the arsenic and antimony, and converts them into arsenate and antimonate of potassium. The solution is then boiled, filtered, to get rid of the oxide of cjpper, evaporated to small bulk, and distilled with ferrous 120 chloride and strong chlorhydric acid. The distillate is then saturated with sulphuretted hydrogen, aiid the arsenic weighed as sulpliidt., after being freed from traczs of sulphur by washing with carbon bi- sulpiiide and alcohol. The residual liquid, from which the arsenic has been thus removed by distillation, is then tested for antimony.Drscussiox Dr. BERXARDDYERdrew attention to a remarkable difference in the results obtsliued on testing for arsenic by Marsh’s process when the zinc used was iu the shape of rods instead of being granulated. Some time since he had detected arsenic, not a mere trace, but, a tangible, weighable quantity, in a certain pigment, but his results were disputed by the maker of the colour, who stated that a test made with rigid precautions by another operator had afforded no evidence of the presence of arsenic. The speaker had therefore met the other operator, and the following very curious results were obtained :-An ounce or two of his (Dr. Dyer’s) highly purified granulated ziric was introduced into the Marsh apparatus, together w;th pure chlor- hydric acid ; at the end of an honr no appreciable deposit was formed in the heated tube, but on introducing 2 gi-aim of the pigment a, dense arsenical mirror was soon obtained.The npparatus was then washed out, and charged with cast rod zinc, brought by the challenging operator ; not only, however, was no deposit formed in the tube during the blank trial, but also on introducing 2 grams of the pigment no indication of the presence of arseiric WRS obtained, although the experiment mas continued during an hour. Further experiments were made with this cast zinc, in which arsenious acid was deliberately added ; when small fractions of a milligram were taken, and gas was slowly evolved, the arsenic was almost completely held back, and was but very partoidly deposited even when several milligrams were taken, the results being altogether difl’erent from those obtained on using the granulated zinc.A number oE samples of cast zinc were found to behave similarly. He had no doubt that Some condition, probably of a physical kind, prevailed in cast ziiic that did not prevail in the case of granulated zinc. The matter required further investigation, as it was one one of obvious import-ance in toxicological work. There was little doubt that the arsenic is precipitated in the geiieratiiig bottle. Even granulated zinc pro-dnces some precipitation. It has been already shown that the fre- quently advocated use OE platinum in the generating bottle tends to hold back arsenic, and it seems probable that some couple may be formed in cast zinc."14. "The action of light in peventing putrefacthe decomFosition and w in inducing the formation of hydrogen peroxide in organic liquios.",By Arthur Richardson, Ph.D. It mas shown in 1878 by Downes and Blunt (Proc. Roy. Xoc., 26, 488) that the development of bacteria and other putrefactive orpn- isms is arrested under the influence of sunlight and oxygen ; Janowski, Buchner and Marshall Ward have recently made observations of a similar character. This sterilising influence of light in presence of ox-j-gen has apparently always been regarded as the outcome of an action exercised within the organism ; the author describes a number of experiments with urine, made with the object of ascertaining whether, when sterilisation has been effected by light., any oxidising agent, such as hydrogen peroxide, is formed, and whether such sub- stance may not be the sterilising agent.The method of testing is fully described, reliance being chiefly placed on the production of a yellow colour on the acidition of a solu-tion of titanic oxide in sulphuyic acid; it is shown that, this test affords a means of accurately estimating small amounts of hydrogen peroxide. The author finds that, although no hydrogen peroxide is formed by the nction of oxygen on sterilised urine in the dark, an appreciable amount is formed on exposing such urine to light, which is a proof that the production of the peroxide is not dependent on the presence of organisms.Urine in which bacteria have once flourished and which has then been sterilised at ZOO0 no longer gives hydrogen per- oxide on insolation. Subs tsnces which dedroy hydrogen peroxide were found to facili- tate growth ; thus, two portions of sterilised urine were exposed to light, during several days, and to one of them was added a quant,ty of sterilised manganese dioxide; both were then placed in a dark cnpboard : whereas both originally contained hydrogen peroxide, after 24 hours that to which no manganese peroxide had been added alone pave t'hc yellow colour with titanic acid; and after 14 days, jungoid growths had deyeloped in the liquid containing manganese lwroxicle, whilc the other portion was stiil clear and contained hydro- gen peroxide.Experiments are described, showing that if peroxide of hydrogen be added to fresh urine, this may be kept during a considerable period in the dark without the peroxide being entirely decompoqed, and that its presence renders the liquid much less prone to undergo change uuder the influence of organisms, while, if added to urine in which fermentative change has already set in, it is rapidly decom- posed. 15. “The supposed saponification of linseed oil by Dutch white lead.” By 3. B,Hannay, F.R.S.E., and Arthur E.Leighton. Statements are quoted from technical writers showing the existence of a belief that white lead acts on the oil in which it is ground, and even indicating that the heat given out in mixing the pigment with oil is due to the occurrence of an iuteraction.The authors show that no beat is given out on mixing oil and white lead without undue friction, and that the heab observed in manufacturing operations is due to the conversion of the energy of the engine into heat by friction. Also that white lead can be freed from oil as readily as any other pigment if a. sufficient quantity be used, but it requires 100 C.C. to every gram of pigment to effect a complete separation. Oleate of lead, whether basic, neutral or acid, is shown to be readily soluble in ether, and it was mixed with white lead, both dry and ground in oil, and then extracted with ether, thus proviiig that iC present it would certainly dissolve in the ether used to extract the oil.The method of testing is described, and it is shown that by passing sulphuretted hydrogen through the ethereal solutioii of the oleate, the faintest trace of oleate can be detected. A series of tests carried out on samples of Dutch white lead pro-duced by the most eminent makers is then described, and it is sliown that no trace of oleate is present in any of them, nor does any in- soluble organic compound cling to the lead after the oil is extracted. It is shown that normal carbonate of lead dissolves in heated oil rno1.c readily than hydrate, and that the hydrate is actually less acted upon at high temperatures than either Dutch white lead or normal carbon- ate, so that the hydrate does not saponify the oil. It is shown that so small a quantity as 0.01 of oleate will seriously darken white lead when exposed to the air, and in presence of diluted sulphuretted hydrogen the smallest quantity of oleate causes the paint to darken when the pure white lead retains its colour, showing that the formation of a, lead oleate would be deleterious.DISCUSSION. Mr. HARLANDremarked that evidence of an action between linseed oil and white lead was to be found in tlw fact that it was impossible to wholly remove the oil from an ordinary white lead paint by means of ether. Mr. BERTRAM said that the action between the linseed oilBLOUNT and white lead did not result in the saponification but in the oxida- tion of the oil, one of the products being “linoxin,” which, though soluble in alcohol, was scarcely soluble in ether.This explained the fact alluded to by Mr. Harland. He took exception to Mr. Hannay’s experiments, on the ground that he had used lead oleate, and not the lead linoleate which would result if any “saponification” occurred in linseed oil. Mr. W. F. REIDdrew attention to the work of Mulder and Petten- kofer, which showed that no “saponi6cation” was effected by dry white lead. It appeared that the white lead promoted slow oxidation of the oil and not “saponification.” The PRESIDENTsaid that he failed to understand the author’s object in bringing such a communication under the notice of the Society. The statements made by the writers referred to could scarcely be taken seriously ; such men would probably be unable to explain what “saponification ” meant. No chemist would suppose that carefully dried white lead and oil, such as the authors used, would interact when carefully mixed, or that even carefully dried caustic soda woulcl act under such conditions.It was apparently the universal belief that Dutch white lead had certain peculiar propetties, but its effect was undoubtedly a complex one, in which probably not oiily the white lead and oil played a part, but also moisture, air, light and time. In reply, Mr. HANRAYsaid that his experiments were made to refute the statement made in several technical manuals on paiots. 16. “Notcs on capillary separation of substances in solution.” ByLester Reed.Although the separation of salts in solution by selective absorption in bibulous paper bas been partly investigated by E. Fischer and E. Schmidmer (ArumZen, 272, 156-169), as I have, in ignorance of their experiments as well as of those of Schonbein, beeti recently in- vestigating the same subject by a somewhat different method, I venture to briefly enumerate some of the observations I have made. My attention was first forcibly drawn to the subject by noticing the wide, colourless, very sharply defined margin which is obtained when a drop of moderately dilute solution of eosin (potassium eoside) is allowed to spread upon filter paper, although a saturated solution ol‘ eosin does not yield this margin. On adding potassium chromate to such a dilute solution of eosin, and repeating the experiment, tlie margin obtained is no longer colourless, but yellow, and the presence of chromate may he at once detectNed in this margin by touching it with a platinum wire moistened in a solution of silver nitrate, which produces a dark red spot on the yellow margin.If this yellow mnrgiii be cut off and extracted with water, a solution of potassium chromate 124 free from eosin is at once obtained ; and, conversely, eosin free from potfwsiuru chromate may be obtained if, after the drying of the drop. a drop of pure water be added and allowed to diffuse outwards from the centre ;the appearance then obtained is that of a dark red central portion surrounded by a, colourless margin, which is again surrouzded by a yellow ring of potassium chromate, a practically complete sepa- ration or analysis of the mixtnre of the two salts being thus effected in a very short time.These, with a few other similar observations, me my initial facts, and naturally suggested the possibility of thus separating many other substances, as well as the use of porous media other than filter paper. I then observed that in some cases there was a very narrow, colourless margin outside the yellow region of a drop of potassium chromate solution which had been allowed to spread on filter paper. At first I was inclined to suspect that this appearance WaR merely caused by the advancing solution crushing together and driving before it, by its expansion, some moisture already present in the filter paper. To prevent the drying of the drops during their expansion, I performed most of the experiments in an atmosphere saturated with aqueous vapour, by placing the filter paper, on which the drop la? on a small porcelain dish containing a little water, coverinq this with a bell jar moistened on the inside with water.When thus treated, a drop of moderately dilute solution of potassium chromate affords a most unmistakable, colourless, moist margin, in which silver nitrate fails to detect cliromate. After this I examined in a similar way the diffusion of a mixed solution of ferric chloride and copper sulpbate, testing the marginal region, after allowing about an hour for expansion, with potassium ferrocyanide, which demon- strated the existence of a marginal ring containing copper but free from iron.'In the case of a soliition of ammonia alum, using as tests for ammonium and aluminium respectively Nessler's test and tinctare of logwood containing ammonium carbonate, no separation of the con- stituents was detected, both extending to the extreme limit of moisture: so that in this case I have not obtained any free water margin, and the same remark will apply to chrome alum. Employ-ing a mixtnre of the solutions of copper sulphnte, ferric chloride and ammonia alum, a beautiful separation is readily affected. Externally in this case there is a ring of pure aliim detectible by the logwuod test, within which is 8n annular zone jointly occupied by copper sulphate and alum, which is shown to be free from iron by yielding a pure chocolate colour with pot,assium ferrocyanide ; and, lastly, a central zone where all three salts are present and which is coloured dark blue hy ferrocyanide, the lines of demarcation between these three zones being perfectly sharp and definite.Jn applying the log-wood test by means of platinum wire, it is neccssary to dry the minute spqtq nncl to compare them with siniilarly dried spots yielded by. the sxme test on clean filter paper. In the absence of alum, the drops are buff; in its presence. pnrple. Mercuric chloride is a salt which, even in sa,t,urated solrltiori, very 1-eadily gives a free water margin. Caustic potash or potassium iodide may be used as tests for it.In a mixture of solutions of lead acetate and mercuric chloride, suffinient.ly dilute to give no precipitate, the lead is observed to outstrip the mercury. Platinum chloride very readily gives a margin, the test employed being reduction by heat; in the case of a strong solution there is a tendency to form a double margin, which suggested to me the thought either that there might be two hydrates of platinum chloride present in solution, each possessed of a, different diffusibility, or else that some of the lower chloride was present. As the width of tlie free water margin yielded in the course of an hour or so, in some cases at any rate, depends very much on the strength of the solution, I prepared a solution of ferric chloride of such strength as to yield no free water margin, and then diluted it until a slight margin began to appear.At this point I analysed the solution, which corresponded roughly to the ratio VeC1, :20UH20. On continuing the dilution in geometrical progression by continuously halving its strength, the free water margin rapidly increased in diameter, being always, however, sepa- rated from the iron region by a sharp line. When a dilution in the ratio of about FeCI, : 30,00OH,O is reached, the iron seems to have almost lost its power of diffusing, getting little, if at all, beyond the space wetted by the drop when it first falls upon the paper. Of course, at this dilution it may be said that we are no longer dealing with ferric chloride, but with the products of its dissociation : and t'his explanation might be adequate but for the fact that an extremely dilute solution of sulphuric acid behaves in the same way.A drop of ferric chloride solution, while spreading upon filter paper, frequently presents an a,ppeamnce, more or jess noticeable, of con-centric rings, suggesting, perhaps, the presence of more than one hjdrate in solution. Imagining that the presence of hydrates in solution might be in some way or other connected with the formation or diameters of these free water margins, I prepared a solution of potassium bicliromate corresponding in strength to Guthrie's cryo- hydrate, viz., K,Cr,O, + 292H,0. It readily yielded a margin of watrr, and it is remarkable that this margin is of abont, the same width as that yielded either by a saturated, or by a very much more dilute, solution of the salt.I continued the dilution of this solution in geometrical progression, as with ferric chloride, until I brought it to 1/128th of the strength of the cryohydrate, but even th;s great dilution had little or no effect on the diameter of the free water margin, a result notably differing from that obtained in the case of 126 ferric chloride or sulphuric acid. Copper sulphate solution, on the other hand, undergoes great change in diameter of free water margin on dilution. Hence it may be enqaired whether a change in the diameter of free water margin, which must obviously represent a change in the relative velocities of water and the dissolved substance, may not in all cases be an evidence either of dissociation or of changcs in the composition of the hydrates existing in solution. Sulphuric acid yields beautifully definite results, the test relied on being that of drying the filter paper at a high temperature, when the portioii over which the acid has extended chars.A free water margin begins to be formed at about the strength of 1part of acid by volume to 200 parts of water; and when a dilution of abont 1 in 4000 is reached, the acid (as was the case with ferric chloride) seems to have almost totally lost its power of diffusing, and yields a relatively enormous free water margin. It would be very interesting if it could be shown that this inner zone of non-diffusible sulphuric acid represents a definite hydrate, the dilfusibility of which is arrested by its enormous molecular weight, perhaps approaching those of such non-diffusible colloidal substances as the albuminoids ; and such a hydrate might possibly be at or near the extreme limit of possible hydration of the acid. With regard to the employment of porous media other than filter paper, I have obtained satisfactory results, both with the mix- ture of potassic chromate and eosin, and with that of ferric chloride and copper sulphate, by using tubes containing powdered kaolin lightly rammed down, upon the top of which the solution was placed and allowed to soak downwards.I liad hoped that this method of separation, or some modification of it, might have prqved available for the separation of alkaloids from organic matters of differentf nature, with a view to their subsequent identification, but have hitherto been very partially successful in this direction.17. "Note on a meta-azo-compound." By R. Meldola and F. B. Burls. While azo-compounds oE the ortho- and para-series can be repre- sented either as hydrazones or as true azo-cumpounds by the formula+-the azo-derivatives of the meta-series- 127 cannot be formulated as hydrazones. We have commenced series of experiments having for their object the preparation of members of the meta-series, in order to institute a comparisoii between their pro- perties and those of the ortho- and para-series.It is obvious hhat a comparative study such as we propose to undertake is calculated to throw light on the question of the constitution of organic colouring matters, as the "quinonoid " bonds are not present in the meta-corn- pounds according to our present method of formulation. As the work must be for the present interrupted, owing to one of us (F. B. B.) having accepted an appointment away from London, we desire to place our results on record in this preliminary cummunication. The first compound with which we exptrimented has not given a decisive result on account of certain practical difficulties which we have not yet succeeded in overcoming. The only satisfactory com-pounds which are worth studying from the present point of view are evidently those of the tjpe C,H,-OH.N,X [OH :N,X = 1: 31, in which X is an uusubstbtuted hydrocarhon radicle.Metamidophenol was diazotised in presence of chlorhydric acid in the iisual way and combined with a-naphtbylamine, also dissolved in chlorhydric acid. The mixture of the two solutions gradually became of a deep violet- red colour. The am-compound was firlally precipitated by the addi- tion of sodium acetate. l'he precipitate was collected, washed with water and parified bg dissolving it in cold dilute caustic soda, filttring and reprecipitating by acetic acid ; it was then digested with dilute ammonia, washed with water and crystallised alternately from dilute alcohol and benzene. Analysis showed that the substance was pure. Calculated for HO.C,H,.N,.C,oH,*NH, : C, 73.03; H, 4-94; N,15.96.Found : C, 73.10 and 73.14 ; H, 5.56 and 5.54 ; N, 15-94. 2Cletu~.,henolu~o-a-naphthyluminemay be fairly assumed to have the constitution expressed by the formula ,-. It crystallises in dnll, orange-coloured needles fusing at 196". Its solution in all solvents is orange-coloured and it possesses strong tinc- torial power as an orange dye-stuff. It is both acid and basic in properties, readily dissolving in cold aqueous solutions of alkalis, forming orange-co1oure.l liquids and also forming well-defined salts with acids. The solutions oE its salts are of a magniticent violet coloui*. If the hydrazone formula be assigned to tlie cornpo~nd, it must be assumed that contact with acids causes its transformation illto a compoucd of the azo-type, as the molecule is strongly basic towards acids aiid the presence of the amido-group is indicated by the readiness with which the cornpound can be diazotised. It dis-solves in strong sulphixric acid, forming a dull, magenta-red coloured solution, becoming violet on dilution, and on the further addition of water the sulphste separates out in bronzy crystals.Of the salts, the hydrochloride was specially examined. This was prepared by dissolv-ing the base in boiling alcohol and adding stxong chlorhydric acid ; the colour of the solution changes from orange to violet; the hydro- chloride separates out on cooling. The salt forms flat needles having a beautiful bronzy lustre.A specimen allowed to dry in the air for some time and then for a day in a vacuum gave the following results on analysis :-Calculated for HO*C,H,*N,*C,,H,*NH,,HCI,H,O: C1, 11.18; N, 1322; HzO, 5.67. Found : C1, 11.36 ; N, 13.1 ; H,O, 5-73. The salt does not part with its water at temperatures below 110-1229', and the loss of Lhe water molecule is accompanied by a change in colour from a metallic Inroi~zs! to a dull green. In order to further characterise tlie azo. compound, the ncetyl derivative was prepared by boiling a solution of the substance in glacial acetic acid with acetic anhydride till the original violet colour of the solution had changed into orange. On pi.ecipitat.ing with water and crystallising the product from dilut,e alcohol, it was discovered by amalgsis that it probably consisted of a mixture of a monacetyl with a diacetyl derivative; this was confirmed by the observation that the compound did not completely dissolve in dilute caustic soda, but left a slight residue.Pnritication was effected by this means, and the dissolved (phenolic) portion, having been precipi- tated by chlorhydric acid, was crystallised from dilute alcohol and then from dilute ayetic acid till the melting point was constant. Bmixtiful golden scales were thus obtained melting at 232-235" and giving on analysis results agreeing with the formula of a mon-ace ty 1 deri rat i ve-Calculated : C, 70.81; H, 4.91; N, 1377. Found: C, 70.53;H, 5-23; N, 13.70. As this compound is phenolic, it is clear that the acetyl displaces amidic hjdrogen and, therefore, that the product has the formula HO*CsHI*Nz.CloHs*NH*C??HJO.It dissolves in alkali, forming an orange-coloured solution and possesses strong tlinctorirtl properties. The non-phenolic derivative was not formed in sufficient quantity to enable us to obtain sufficient for complete examination.The melting point, aftler several crystallisations from dilute alcohol and benzene, was about 226" and the nitrogen approximated in quantity to that required by the diacetyl derivative. The substance forms flat needles of a golden colour and is also an orange colonring-matter. As it is non-phenolic, the hydroxylic hydrogen is probably displaced as repre- sented by the formula.CzH130*0*CGH,*Nz*C,,H,.N1~.C,H,0. The maiii object of the present investigation could not be realisetl in this case owing to the impossibility of displacing the NH, group by H. The method usually adopted in such cases was tried under various conditions, but the product was always a brown, uncrystallis- able, resinous substance, which could not be purified by any artifice so as to give satisfactory results on analjsis. The substance was phenolic and dissolved in alliali, forming a brown coloured liquid. It may have contained the naphthaleneazometaphenol sought for, but in its impure condition we could draw no conclusion with respect to its colour properties. The experiments are therefore being extended to other compounds of the same series.18. " The influence of moisture in promoting chemical action. Pre-linzinaxy note." By H. Brereton Baker, M.A. It has been shown by the author (C.rs'.Trtrns., 1885; Phil. T~ans., 1888) that when moisture is removed as completely as possible, certain substances, e.g., carbon, sulphur, phosphorus &c., can be heated in an atmosphere of oxygen without undergoing visible combustion ; and he has been engaged during the last ttwo years in contiiiuing the investigation, with the object of ascertaining in what way moLture promotes chemical action. One of the cases which he has studied is the formation of arrirrionium chloride from ammonia and hydrogen chloride. A difficulty presented itself at tlie outset in drying am- monia gas, as it is absorbed by phosphoric oxide; this was overcome by drying the gas as completely as possible by freshly ignited lime, after which it, was found that phosphoric oxide did not absorb any appreciable quantity.Hydrogen chloride was dried in a similar way by sulphuric acid and finally by a week's contact with phosphoric oxide. On allowing the dried gases to mix, NO ammonium c1doriJe j&jzes were produced, and no contraction was indicated by the mercury gauge attached to the apparatus ; and it may therefore bc concluded that ammonia and hydrogen chloride do not combine when dry. Ov introducing a small quautity of moist air, union at once takes ])lace, however. In like nianner, sulphur trioxide was found not to unite either with lime or barium monoxide or copper oxide.Further-more, no brown fumes were produced on mixing dry nitric oxide with dry oxygen. The author is engaged in studying the effect of moisture on various types of chemical action, and he hopes soon to be able to communicate the results to the Society. "19. "The genesis of new derivatives of camphor containing halogensby the action of heat on sulphonic chlorides." By F. Stanley Kipping, Ph.D., D.Sc., and W. J. Pope. When the sulphonic chlorides described in a recent paper are heated at temperatures not very far above their melting points, they undergo decomposition, sulphur dioxide being evolved. In the case of camphorsulphonic chloride, chlorocamphor is produce I, in accord- ance with the equation C,,Hl,O*SO,Cl = C,,,H150Cl+ SO,; at the same time a considerable quantity of an oil is formed, the nature of which remains to be determined. This chlorocamphor separates from cold dilute alcohol in arborescent forms; it melts at 137-138"; analyses gave C = 64.26: H = 8.47, C1 = 19.35; C,oH,60CI requires C = 64.37,H = 8.04, C1 = 19*09.By heating chlorocamphorsulphonic chloride, a well-defined di-chlorocamphor is obtained, which crystallises from light petroleum ih long prisms melting at 118-119"; like the sulphonic chloride from which it is derived, it is dext.rc:rotatory, its specific rotation in chloroform solution being a little higher than that of either of the known dichlorocamphors, namely, [&ID = 85". Analyses gave C = 54.27, H = 6 66, C1 = 31-84 and 32.04; CloH,,OC1, requires C = 54-34,H = 6.34, C1 = 31-99, The compound prepared from bromocamphorsulphonic chloride closely resembles dichlorocamphor and crgstallises from light petr- oleum in lustrous prisms melting at 142-143'; like the latter, it has a, high specific rotatory power, namely, [a]~= 104O,in chloroform solution.These three derivatives of camphor appear to be different from any known compounds, and their further study will, it is hoped, throw light on the complex question of isomerism in tho camphor series ; it is possible that, starting from the corresponding sulphobromides, it will be possible to obtain new bromo-, dibromo- and bromocl~loro- camphor derivatives, and in this way to establish fresh cases of isomerism ; experiments with this object in view are in progress. Ur.Armstrong informs us that Dr. Wynrie and he have noticed in the course of their studies of naphthalene derivatives ihat a number of sulphochlorides undergo deconiposition when heated above their melting points, and that Dr. Wynne has observed that the sulpho- chlorides of some of the chlorinated toluenes behave similarly. The study of the behaviour of sulphochlorides and allied conipounds generally when heated is therefore desirable, and nil1 be carried on in the Central Institution laboratory. 132 EXTRAMEETING.-May 5th, 1893. Dr. Armstrong, President, in the Chair. HOFMANN MEMORIAL ADDRESSES. The PRESIDENT,in openinq the proceedings, said they were met to do honour to the memory of a man to whom chemists throughoilt the world, and especially British chemists, are very deeply indebted --probably to a far greater extent than we shall ever be able to realise ; a man who on account of his niarvellous and manifold gifts will undoubtedly rank among the chemists of the Victorian era as second only to his great master Liebig. Hofmann, even if judged by his published work alone, would take the very highest position ; but those who had known the man, however slightly, were aware that he was possessed of rare personal gifts which enabled him to exercise an influence extending far beyond the limits to which any purely scientific worker can attain.It is on this account very difficult to Secure a satisfactory presentment of the man and especially of the influence which he directly and indirectly exercised on the develop- ment oE chemical science and its industrial application.They, how-ever, were fortanate in that they had succeeded in inducing several of the Fellows to co-operate in this arduous task, and although they could not hope to do all that is necessary, t.he contribution the Society was thus able to make will be exceptionally valuable, as the three gentle-men who would speak of Hofmann that night all had peculiar quali- fications. Lord Playfair, in days long ago, dwelt happily in the rerdant and fertile fields of science, and the more often we had evidence of his perennial and vigorous youthfulness the more we must lament that he was ever led away into the tortuous paths of politics; in those almost prehistoric times he was not a mere spcctator but an active worker, his name being associated in the records of science with those of the giants Bunseii and Joule.Among others there was a paper by him on “ Transformations produced by catalytic bodies,” published 45 years ago in the Society’s memoirs, which was worthy of perusal even now and which, he ventured to think, dis- played greater philosophic grasp of the problem than the more recent essays on the subject. He had been astonished in reading through the early minutes of the Society to see how active an interest the then Dr. Lyoo Plq-fsirtook in their work: how he was 133 always proposing that, something new slionlct be done, aid how vwy frequently his proposals were carried into effect. No one was so well qualified as was Lord Playfair to picnture to us the state of affairs chemical at the time of Hofmann’s arrival here.Sir Frederick Abel’s qualifications were of a different order-he would speak directly of the man and of the conditions under which he worked at an especially interesting period in his career. He believed that Sir F. Abel’s name was first on the list of Hofmann’s first set of students, and that he was his first English assistant; he soon became and ever afterwards remained, he might say, his willing slave as well as friend, for Hofmann had the power- and hence his marvellous influence-of enslaving all who came under him, and of makicg them, whether they willed it or no, do the best work they were capable of. Sir Frederick Abel by virtue of his oFportunities and his abilities was the man to whom alone we could look on the present occasion.His devotion to the Society was well known to most of the Fellows ; but there were few besides the oficers who have been concerned with him in the management of its affairs who are fully aware of the extent to which ho had served the Society. His presence there to-night was in itself sufficient evidence of tbe deep interest he still took in their work and of his willingness to sacrifice himself; as all knew, at the present time, he was engaged in the conduct of an enterprise of extreme difficulty and magnitude-more than su6jcient to tax the powers of the majority of men, but which appeared in no way to satisfy his insatiable greed of work.Of Dr. Perkin, who would speak of the outcome of a part of Hof-mann’s scientific work, it was needless to say much. He was a man of whom it could truly be said. that his works are the measure of his worth. If the wdls of the room in which they were assembled could speak, it would he of his labours before all others that they would have to tell. The story that. he had to relate was of entrancing interest-a true tale of magic, but full of deepest moral. Lord PLAYFAIRsaid that, although, when he was at Giessen, Hof-mann was about two yeais his senior in age, Hofmann was studying mathematics and physics, and although he mixed with the active workers in Liebig’s laboratory, he was not one of the body, and did not begin to work there until some time afterwards ; it was originally intended that he should devote himself to philology and law, of which he was during some time a student.Eeferring to his remarkable linguistic powers, he said he had heard him make speeches in several languages, and especially remembered one occasion when, in 1867, at a memorable banquet given by the French chemists to those of foreign countries, Hofmann proposed the health of their hosts in a capital French speech. He then spoke of the position of chemistry in England prior to Hofmann’s arrival. Both in the last and the early part of the pre- sent century, England was not wanting in great chemical investigators. Among others, Lord Playfair referred to Dalton, incidentally men- tioning that he could never forget seeing his venerable figure, sup-ported on the arm of Dr.Joule, come daily to hear him lecture at Manchester on organic chemistry. Except Grahnin, under whom the speaker studied in Glasgow in 1835-36, following him to Loiidon as private laboratory assktant, no one, however, had thought of opening his laboratory to students. Graham’s example, however, spead, and seveid colleges, and even the universities, slowly adopted the view that laboratories were necessary to teach and train the chemists of the future ; but all who desired to study organic chemistry flocked to Cfiesuen, and returning from there acted as missionaries in spread- ing a knowledge of the new organic chemisiry.An extraordinary influence was exercised by the publication, in 1€!40, of Liebig’s celebrated work, Chenzistry of Agriculture and Physiology, which was heightened by a triumphal tcur, made two years later, by Liebig, through this country, in which he WRB personally conducted by the speaker. The immediate effect of Liebig’s tour was to make chemistry a popular science, and to induce colleges to open laboratories, and hence it was that the Royal College of Chemistry was founded in 1845. Two wise men were mainly instrumental in its establishment -the Prince Consort, and the Queen’s physician, Sir Janies Clark. They saw that all the chemical laboratories in existence in this country were mere accessories or subordinate to professional training, the students entering them rarely wishing to become chemists ; and they desired to found a college where chemistry might be studied for its own sake.A college of this kind without endowments could not have been created unless a strong popular feeling had arisen, such as Liebig’s work had promoted. After referring to Hofmann’s appointment, his remarkable lucidity, and his marvellous powers of exciting enthusiasm, Lord Playfair spoke of the early success of the College of Chemistry, and then pro- ceeded fo explain how it was that it so soon ceased to exist as an independent institution. Every landowner had thought that Liebig’s book was to be his salvation, and when it was found not to produce the expected results, popular belief in chemistry declined, and the support accorded to the college gradually dwindled.At this time the speaker resigned his professorship at the School of Mines, and Hofmann succeeded him, carrying with him the College of Chemistry, which then ceased to be an independent institution : the 135 change was inevitable under the circumstances, but it was not good eikher for the college or chemical science. No doubt Hofmsnn felt this, and was affected by it when hewas offered a professorship in the Berlin University, where he went in 1864. Lord Playfair concluded his a.ddress by expressing the hope that he might live to see a new college or institute arise like a phoenix from’ the ashes of the old one, perhaps in connection with higher university teaching in London, as a supplement to, and not in competition with, existing laboratories, in which chemistry might be taught as an in depend en t subject.Sir FREDERICKABEL,at the outset of his address, referred to ths commencement of his own career as a chemist as an illustration of the difficulties attending the attempts of young beginners with limited resomces to acquire a knowledge of practical and analytical chemistry, with a view of adopting the science as a profession, half a century ago. In the autumn of 1844, he had entered the laboratory of the Royal Polytechnic Institution, only to find that the sole means of acquiring some practical knowledge consisted in plodding unaided through Brande’s Manual, endeavouring to acquire experimental skill by preparing the elements and t,heir compounds according to the directions therein given, and to become acquainted with analpis by following Andrew Parnell’s tables.Several other young chemists, who afterwards became prominerit pupils of Hofmann, were in a similar position at that time, and so, when the temporary laboratories of the new college were opened in the autumn of 1845, there was a small band of aspirants impatiently waiting to avail themselves of the benefits of the system of instruction which had already acquired so high a reputation on the Continent. Sir Frederick then recited the history of the efforts ma-de in this country as early as 1843 to establish an institution where the sys-tematic study of chemistry as a profession in itself could be pursued, referring to the prominent part taken in the matter by Dr.John Gardner, the translator of Liebig’s Letters on Chemistry, and Mr. J. Lloyd Bullock, one of Liebig’s earlier pupils, and pointing out how very nearly a National Practical School of Chemistry became asso- ciated with the Royal Institution. After the failnre of the negotia- tions with the Royal Institution, the agitation was continued, and ultimately, at a public meeting at the temporary offices of the College of Chemistry on July 29, 1845, a definite form was given to the proposed Institution, and a Council and Executive Officers were ap- pointed, after which the first all-important subject to receive anxious Consideration was the appointment of a Professor.The circumstances attending Hofmann’s appointment were next referred to, Temporary laboratories were fitted up in George Street. Twenty-six students entered in the first session, among whom were F. A. Abel, C. L. Bloxam, Warren De la Rue, R,Galloway, Henry How, E. C. Nicholson and Thomas Rowney. Hofmann’s complete sway over his pupils, said Sir F. Abel, was at once secured Ly his indomitable perseverance and inexhaufitible patience with the dullest, his earnestness of manner, his clearness of exposition, rendered additionally attractive by an inlierent quaintness and a power of happily rendering German expressions into graphic English.Those first two sessions of the C.ollege, in the scantily equipped laboratories, with make-shift contrivances of the crudest character and an utter absence of any convenience for conducting investigations, must have been a sore trial of patience and powers o€ endurance to the impetuous young teacher, and to the enthusiastic worker, whose only recreation was the pursuit of original research When to these circutnstances is added the mental strain involved in the almost coiitinuous pursuit of instruction and discussion in a foreign language, for at least eight hours daily, to say nothing of continued anxious consultations with the Council and officials of the College regarding ways and means ; the heavy work connected with the erection and equipment of the permanent laboratories; the grappling with the problems of maintaining and fostering public interest in the Inst’itution, and of keeping current expenses within very moderate bounds: it is self-evident that no small moral courage and powers of endurance were needed for the successful .accomplish- ment of these duties; for tlre maintenance of the confident and apparently light-hearted demeanour, and of the power of instilling into others confidence of future success, which were peculiarly cha- racteristic of Hofmann in those days of supreme difficulty.But these very characteristics, added to his genial and charming manner, high flow of spirits and originality in conversation and correspond- ence, secured to him devoted friends, not merely among colleagues and pupils, but in whichever direction social intercourse was opened up to him.Just as his earnestness of purpose and enthusiasm kindled corresponding qualities in a large proportion of his pupils, so also his sanguine temperament, and airy treatment of difficulties maintained, among many of the early fieiends and important patrons of the struggling Institution, a steadfastness of purpose which other- wise would doubtless have speedily waned. Hofmann’s method of teaching and his powers as a lecturer were next alluded t,o. Thirty-seven students entered in the second session, making sixty- three in all, arid the laboratories became inconveniently crowded. Thc third session was commenced in tlic new laboratories in Oxford Street in October, 1846.These inclxded a small private laboratory for the Professor, and here Hofmann at once resumed research work, Nicholson acting as his assistant. There is but one opinion among those who can appreciate the stiipendous difficulty of the task so brilliantly accomplished by Hof-mann, in placing the College of Chemistry upon a sure foundation, and in securing to it, within a rery few years, a high position among the chemical schools of Europe-tbat his success was ascribable to the possession of a happy and rare combination of the highest talents as a teacher with exceptional powers as an investigator, in- exhaustible industry and energy, and an enthusiasm not to be sub- dued by any obstacles-a characteristic quality possessed in the highest degree by his great master, Liebig.The severity of work and many-sided training which those who assisted Hofmann in the early days of the College of Chemistrj was illustrated by an account of Sir F. Abel’s experience during five years as an assistant. Sir F. Abel then referred to the more prominent pupils of Hof-mann ; to the character of the researches carried on in the College ; to Hofmann’s faculty of gauging the abilities and special qualifications of those who worked under him, and his power of directing and stimulating them : to his marvellous literary and linguistic skill ; and to the ease with which he made friends. The pleasure with which he always referred to his career in London was illustrated bg a letter addressed by Hofmenn to the Prince of Wales, who, as President of the Society of Arts, wrote to him, in 1882, congratu-lating him on being the recipient of the Albert medal.Dr. PERKINsaid that he was charged with the duty of giving an account of the rise and progress of the coal-tar colour industry, wibh which Hofmann’s name was so inseparably connected, which he had been requested to make to a large extent autobiographical. Aniline was Hofmann’s first love, the subject of his first research, and he was the first to recognise the preseiice of benzene in coal tar ; in 1845, at his instigation, Charles Mansfield undertook the investi- gation of the coal-tar light oils, in the course of which he sacrificed his life, while obtaining results of the utmost value, both scientifically and technically.Dr. Perkin said that he entered as a student under Hofmann when in his 15th year, at the time when the Royal College of Chemistry became a part of the School of Mines: he soon got through the ordinary analytical course, and began to work at research- the problem which he was set by Hofmann to solve being to prepare a,base from the hydrocarbon anthracene. Although the desired base WBS not obtained, the compound now known as anthraquinone was 138 prepared, and also chloro- and bromo-derivatives of anthrmene, but the results of the analyses were unintelligible, and it never occnrred to them to doubt the correctness (f Dumas and Laurent’s formula for anthracene, C,6H,2.The experience thus gained, however, proved of great value later on. When in his 17th year, he was promoted to the position of an assistant in the Research Laboratory, and as he had necessarily little time for private work in the day time, a room at home was roughly fitted up where he was able to work in the evenings and during vaca- tions. Here a research was carried on joint’ly with Mr. Church, also an assistant in the Research Laboratory at the College, on some colouring matters derived from dinitrobenzene and dinitronaphthal- ene, in the course of which amidoazonaphthalene was prepared, which appears to have been the first compound obtained of the diazo- cl~ssshown to poqsess dyeing powers. At about this time the artificial formation of natural organic sub-stances attracted much attention, and Hofmann specially referred to the importance of preparing quinine in his report of the Rojal College of Chemistry, pointing out that, judging from its composi-tion, it might be a derivativeof naphthylamine.Dr. Perkin said that as a young chemist he was ambitious to work on the subject and, probably fired by Hofmann’s remarks, began to think how quinine might be formed : it occurred to him that it mighl, be produced by oxidising allyltoluidine, and experiments in this direction were accordingly made-needless to say, to no purpose, but the results led him to experiment on the oxidation of salts of aniline, and on using potassium bichromate a prodnct was obtained containing among other substances the coiouring matter afterwards known as aniline purple, Tyrian purple or mauve.These experiments were made at home in the Easter vacation of 1856. In the summer vacation the preparation of the colouring matter was undertaken on a small technical scale in the back garden at home, and ultimately the process was pa’ented on August 26, 1856. Not long afterwards, in conjunction with his father and brothep, he oommenced the manu- fhct ure of the dye. The extraordinary difliculties to be overcome were then referred to ; not only had all the mechanical appliances to be devised, but at this time benzene was made in but small quantities arid nitric acid of sufficient strength could not be procured com- mercially ; moreover, methods oi dyeing with the new colour had to be worked out.Dr. Perkin then referred to the discovery of fuchsine (rosaniline) in France, and explained how Messrs. Simpson, Made and Nichol- son, originally manufacturers of fine chemicals, began its manufacture. Through Nicholson, Hofmann at this time exercised an all-important 139 influence on the industry. Hofmann had always insisted or1 tlie abso- lute necessity of obtniniiig products in as nearly pure a condition as possible, and had thoroughly imbued Nicholson, who had carried out several investigatioiis under him, with this idea ; owing to Nicholson’s skill, his firm soon succeeded in supplying fuchsine in a crystallieed condition, and the example thus set has been of the greatest value. Hofmarin’s own early investigations of rosaniline and its various derivatives were then refelred to, and, after sketching the further developments of the industry, Dr.Perliin drew attelltion to Hof-mann’s various researches bearing on derivatives of coal-tar products. In the latter part of his address he more briefly referred to the rise of the alimrin industry, pointing out that, although Hofmann had taken no part in this, it was undoubtedly the fact that his early introduction to anthracene, which he owed to Hofmann, was the cause of his becoming interested in the subject immediately Graebe and Liebermann’s great discovery was announced. As in the case of the aniline colour industry, so in that of the alizarin industry, all tlie necessary machinery had to be devised, and many of the materials required had to be specially prepared for the pnrpose.Hofmmn’s researches in connection with coal- tar colouring matters extended over a period of 25 years, from 1862 to 1887, and through these and the training which he imparted to those of his students who took part in the industry he exercised an influence unique in the history OF modern industrial enterprise. ADDITIONS TO THE LIBRARY. I. Donations. Annual Report of the U.S.X. National Board of Health, 1882. Washington 1833. From the Secretary of the Treasury, U.S.A. U.8.Geographical and Geological Survey of the Rocky Mountain Region ; Contrihations to North American Ethnology. Vol. V11. A Dakota-English Dictionary, by S.R. Riggs; edited by J. 0. Dorsey. Washington 1890. From the Director of the Survey. Smithsonian Institution : Seventh Annual Report of the Bureau of Ethnology, 1885-6, by J. \V. Powell. From the Institution. 11. By Purchase. Carl Wilhelm Scheele : Nachgelassene Eriefe und Aufzeichnungen, herausgegeben von A. E. Nordenskiijld. Stockholm 1892. A Dictionary of Applied Chemistry, by T. E. Thorpe. Vol. I11 London 1893. 140 RESEARCH FUND. A meeting of the Research Fund Committee will be held in June. Fellows desiring grants are requested to make application before June 10th. NOTICE TO AUTHORS OF PAPERS. Authors are particularly reqiiested to send their papers to the Secretaries, at Burlington House, not later than the ittonday p~sz;ious to the meeting at which they are to he read. In all cases an abstract oE each paper should be supplied for inser-tion in the “ Proceedings.”
ISSN:0369-8718
DOI:10.1039/PL8930900117
出版商:RSC
年代:1893
数据来源: RSC
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