316 Correspondence-Miscellaneous. CHEMICAL News, they are then removed, gently tapped to facilitate the for- benzoic acid one fourth the weight of the arseniate of mation of a single button, and allowed to cool. Upon rosaniline. These proportions produced a really good breaking the crucibles the reduced metal should present blue after purification. He purified with ether, which an almost silvery lustre, with a clean upper layer of removed the unchanged aniline and the tarry matters melted flux. I have usually taken the precaution of dis- formed; after that the dye was ready for the market. solving the latter in water for the purpose of satisfying | He purified in another way, by treating the melt with myself in regard to the absence of any trace of reduced alcohol and then with diluted hydrochloric acid; the dye metal or heavy particles of the original ore. There is was then washed, separated by filtration, and dried. Or always contained in the commercial cyanide a sufficient he washed the melt (bronze mass) with acetic acid, quantity of alkaline carbonate to secure the perfect fusion and used ether when much tar was present. It of the silicious gangue and other like impurities in the tin was immaterial which method of purification was ore, but the operator should assure himself of the absence used. He made many experiments to obtain blue. of copper and lead in the ore, either by preliminary treat- If the arseniate of rosaniline was replaced by the acetate, ment with hydrochloric acid, in which tin-stone is abso- an equally good colour was produced. Arseniate of roslute insoluble, or by testing the button of reduced tin aniline, aniline, and acetate of soda also made a good after hammering or rolling for such metallic admixture. I colour. The result was the same with acetic as with benhave usually found a minute trace of iron, and sometimes zoic acid, but without either benzoic or acetic acid no gold in the melted buttons, but not so much as to add bronze-coloured mass was obtained. Benzoate of aniline appreciably to their weight. decomposes at 150°C.; most of the aniline salts part with aniline at 150°C. He knew Girard's specification. Had tried the process in Germany because he wanted to dispense with benzoic acid. With Girard's process very little change took place. He never got blue without benzoic or acetic acid. Had made experiments with Girard's patent in conjunction with Dr. Miller, but did not remain until the experiments were completed. Knew the tests for acetic acid and acetanilide, but had never seen acetanilide. Sulphuric acid would detect acetic acid; small quantities would be detected by the kakodyle test. My experiments have sometimes furnished identical results, but I would rather state of this process that when worked with ordinary care it may be relied upon as giving numbers true to within per cent., and I do not know any other method which exceeds this in accuracy and rapidity of execution. I append a few analytical results taken at random from a number of ores assayed in this manner : Tin per cent. I. 45.6 II. 45'8 576 MISCELLANEOUS. RENARD v. LEVINSTEIN.* (Continued from page 312.) IN the course of Mr. Jessel's speech for the defendant, a question arose upon Girard's patent of 1860. This was for the production of colouring matter simply, not for dyes specially, but an allusion to a blue colour was looked upon as a prior publication of the process of 1861. Some of the plaintiff's witnesses were therefore recalled to prove that the two patents were for substantially different matters. We need not further allude to this part of the proceeding, as it only formed an episode in the trial, but proceed now with the evidence for the defendants. The first witness called was Professor J. A. Wanklyn, who was examined by Mr. Aston. He said he had considerable experience in the mode of making aniline blue, having manufactured and sold it in Heidelberg in 1862-3. He made the blue in two ways. In one he used the red aniline dye commonly known in Germany; this was the arseniate of rosaniline, and was moist with hygroscopic water. To this he added aniline, and heated. While the mixture was hot he added benzoic acid, and continued the heat for a time until a bronze mass was formed, which was semi-fluid while hot, and solid when cold. He took from time to time a portion out of the vessel, and dissolved it in alcohol, and as soon as the solution was blue the process was finished and the dye was perfect. In general he heated to 170° C., but the temperature might at times be higher, and at times lower. After the benzoic acid was added the process soon came to a close, generally in an hour. The proportions he used were one part of arseniate of rosaniline, one and a-half parts of aniline, but the proportion of aniline was not material, and of Our report is necessarily confined to the scientific part of the evidence. Of the personal matters in dispute we shall take no account. Cross-examined by Mr. Grove: Small quantities of acetanilide could not be detected. Has taken out two patents, one of which is completed. Patented the use of benzoic acid in November or December, 1862. Had experimented and manufactured perhaps two or three cwt. of the colour in Germany. A manufactory was started in London in 1863, and is still going on. The defendant, Levinstein, works under a license from me. I do not assist in the manufacture; have made the colour to show people. I have a patent for making purple dyes from manna sugar. Have never seen the operation at work. Have never seen aniline used in the process, but rosaniline in some form or other is used. I don't know the proportions of manna sugar used. Cannot tell the chemical reason why benzoic acid produces the colour quicker, and in operation. Can only say the process goes better. Have patented a purple dye called "Avelia." It is an organic dye. Re-examined by Mr. Jessel: You cannot get a blue by Girard's process with an inorganic acid and without an organic acid in some form or other either in a salt or free. With an organic acid you get the blue at one operation. The red gradually becomes blue. Mr. D. Campbell, examined by Mr. Jessel: Is familiar with several aniline dyes, and knows Girard's patent of 1861. Tried experiments with it in 1861 or '62. Obtained a good violet by the first part of the process, but not a true blue by the second. All his experiments with the second part were failures; got only a dirty greyish blue with the chloride; with the arseniate got better. Followed the directions of the specification carefully, and did his best to get the colour. Tried solid and liquid red aniline dyes; tried all the red aniline dyes he knew. The first experiments were made for his own information. First heard of acetate of rosaniline at the Exhibition of 1862. Has heard of the oxalate recently, but is not aware that it is sold now. In 1861 only the arseniate and chloride of rosaniline were sold as red aniline dyes. Made experiments for the defendant with Girard's patent in April, 1864. Got no better results than in his former experiments. Tried acetic acid afterwards, and soon obtained the violet, and afterwards the blue. The violet was obtained immediately, and the blue in about an hour. Had never tried the oxalate. Used equal parts of aniline and acetate of rosaniline; heated them from 320° to 350° F. for an hour. NEWS Bought red aniline dye of Judson and Sons; got a solution of chloride of rosaniline and used it. Did not get a good colour. Tested the solution, and found no acetic acid, so assumed it was chloride. When benzoic acid was added to the chloride of rosaniline and aniline after they had been heated for some time, you get a blue directly, or in an hour. With arseniate of rosaniline you get the same result, when benzoic acid is used. The result has some red in it, and the blue is not pure, but it is good. Two ounces of arseniate of rosaniline, three ounces of aniline, and a half-an-ounce of acetate of soda heated for three-quarters of an hour gave a blue mass on the addition of twenty-five grains of benzoic acid. The same proportions of the other ingredients, but without the benzoic acid, gave a blue, but not so good. In purifying these, he only heated once for a quarter of an hour with hydrochloric acid. This was to remove the excess of red and aniline. Sulphuric acid would do the same, but hydrochloric is the best. The first part of Girard's patent, using solid acetate of rosaniline, and heating for an hour, gives a blue at once, without any violet stage. Had always bad results with solutions of salts of rosaniline. Tried rosaniline with three times its weight of aniline, and with glacial acetic acid; heated them together up to 330°-370° F. for seventy minutes, and obtained a good blue. The red aniline dyes at the date of the patent were the arseniate and that made with nitrate of mercury. Red aniline dye was always an inorganic salt, unless afterwards converted into an organic. No good dye could be obtained by Girard's specification. Cross-examined by Mr. Grove Had made no experiments with the patent of 1860. In experiments with the patent of 1861 used the exact proportions mentioned in the specification. Only knew the chloride and arseniate at the time. The chemical composition of the dyes was not known at the time. Used pure crystals of salt of rosaniline, and dissolved them to see if the solution would answer. Dissolved half an ounce of crystals in ten ounces of water. Obtained the acetate of rosaniline he experi mented with from Dr. Miller. Mr. Crookes, examined by Mr. Aston: Was well acquainted with the subjects of light and colour, and was an early experimenter with the spectroscope. Had subjected colours produced by Girard's specification to spectrum analysis. They were either purple or violet, but not blue. Had applied to a chemist for what was known as red aniline dye at the date of the patent, and had been furnished with a moist red mass. It was a very impure material, and contained mercury. Treated the powder with spirit, evaporated the solution obtained, and used the residue for red aniline dye, "purified in the usual manner." Used half an ounce of this residue and half an ounce of commercial aniline. Did not test the aniline. Mixed the materials in a flask, and heated to 165 C., or as near as possible, for five and a half hours. The result was a solid mass of a bronze colour; boiled this with water and hydrochloric acid-one part of acid to 100 parts of water: obtained a red solution which was thrown away. A residue was left which would dye a violet. Treated this for blue by boiling with hydrochloric acid diluted with ten parts of water; boiled it two or three times. A very small residue was left-not 20th of the ingredients. Dissolved this in spirit: it was more blue than the original violet, but not a pure blue. Examined that solution and others with the spectroscope. Obtained specimens made by Girard's process, and specimens made by the defendant's process, from Dr. Miller. In solution (1 in 250) the blue made by Girard's process was opaque to the orange yellow and most of the green rays, but transparent to the red and blue. A solution of the same strength of the defendant's blue was quite opaque to red. The defendant's was a pure aniline blue; Girard's appeared to be a mixture of aniline red and aniline blue. The spectrum experiments showed a decided difference between the defendant's blue and Girard's. Cross-examined by Mr. Grove: The solution (produced) was made with spirit and water. It was a perfect solution, although it might contain some flocculi. Matter in solution and suspension might, in a few exceptional cases, give different effects in the spectroscope. The violet was a mixture of red and blue, and would necessarily be made more blue by getting rid of the red. Dr. Letheby, examined by Mr. Bagshawe: [The commencement of Dr. Letheby's evidence was not heard by our reporter.] He had tried Girard's process, and heated the mixture for three or four hours. The result was a dirty violet mass. Indications of decomposition were observed at the expiration of the time stated, so the operation was stopped. Treated the violet mass with very dilute hydrochloric acid. Made a comparative experiment with crude magenta red, and obtained a similar result, but not so bright as in the former case. Treated the mass with stronger hydrochloric acid for the blue; used a solution containing 10 per cent. of commercial hydrochloric acid. Obtained a dirty blue mass which would only dye a dirty blue. Made other experiments with the same proportions of purified magenta and aniline, and one-third the weight of acetate of potash, and also acetate of soda. Heated these mixtures to 165° C. for one hour. With acetate of potash obtained a rich blue at once, which required no further treatment. When acetate of potash is used, believed that the chemical changes which take place are essentially different to what takes place in Girard's process. Benzoic acid acted like acetic in expediting the change. Made no quantitative experiments, but believed that the blue amounted to about one-eighth of the ingredients. dyer. In the experiment, which lasted an hour and a-half, Cross-examined by Mr. Grove: Was not an experienced obtained a reddish violet mass. The decomposition was shown by the mass turning brown, which showed that there was an end of the profitable change. Did not know was used there was a copious evolution of ammonia, but the nature of the decomposition. When acetate of potash without acetate of potash little or no ammonia was evolved. In the one case the blue obtained is not pure, in the other it is. In following precisely the instructions of the patent there is a great waste of aniline and red aniline dye, and the manufacture would not be profitable. Re-examined by Mr. Bagshawe: The blue with acetate of potash was obtained without washing; no purification was required. All the material was converted. Could not say whether the products were essentially different or not. Dr. Miller, examined by Mr. Jessel: Had experimented with Girard's patent of 1861. Used equal weights of arseniate of rosaniline and commercial aniline, and heated the mixture to 160° C. (320° F.) for six hours. Obtained a deep violet mass with a bronze lustre. Boiled the mass with dilute hydrochloric acid, and afterwards with one of hydrochloric acid to ten of water. Did not obtain a blue. Boiled afterwards repeatedly with one of hydrochloric acid to twenty of water until the liquor was colourless. Dissolved the residue in methylated spirit; the solution was purple. The best results obtained by Girard's process was not a good blue. [Specimen produced, which Mr. Grove pronounced to be a good blue.] Had not dyed with the solution. Showed specimens of blue produced with acetic acid; these were much superior. By Girard's process only a small proportion of blue was obtained. In the acetic acid process the whole mass was converted. Had made experiments under directions from the defendant. Heated half an ounce of arseniate of rosaniline, half an ounce of acetate of soda, and an ounce and a-half of aniline to 320-330° F. from fifty-five minutes to an hour and a-quarter. In both experiments a blue mass with a coppery lustre was obtained. It was purified by boiling with strong hydrochloric acid; and a good blue was procured at once. Tried chloride of rosaniline accord 318 Miscellaneous-Answers to Correspondents. Used ing to the patent, and got an inferior result. Cross-examined by Mr. Grove: Obtained the best colour with acetate of soda and benzoic acid. That colour did not seem violet. There were no absolutely pure colours in nature. [Nothing of importance was elicited in the remainder of Dr. Miller's cross-examination; but it may be worth mentioning that in course of it a question arose as to what degree Centigrade was equal to 320° F. Several chemists in court volunteered to calculate this, and the following were some of the results called out:-140° C., 145° C., 143° C., 160° C.] CHEMICAL NEWS, Dec. 31, 1864. Science in the Witness-Box. - A writer in Blackwood's Magazine makes the following remarks on the examination of scientific witnesses in courts of law :-"The grandest achievement of all is a poisoning case-something that is to be two-thirds emotional and one-third scientific- where the interest vacillates between the most powerful passions and the pangs of arsenic; and the listener is alternately carried from the domestic hearth to the laboratory and back again. Now, when one is aware that the 'learned Serjeant' knows as much about chemistry as a washerwoman does of the wave theory,' the display of impromptu learning he makes is positively astounding. Armed with an hour's reading of Beck and Orfila, the great man comes down to court to puzzle, bewilder, and very often to confute men of real ability and acquirement; to hold them up to the world as hopelessly ignorant of all that they had devoted their lives to master; and in some cases to exhibit the very science they profess as a mass of crude disjointed facts, from which no inference could be drawn, or a safe conclusion derived. A pitiable spectacle is that poor man of science, pilloried up in the witness-box, and pelted by the flippant ignorance of his examiner! What a contrast between the diffident caution of true knowledge, and the bold assurance, the chuckling confidence, the vainglorious self-satisfaction, and mock triumphant delight of his questioner! Mark the practised leer, the Old Bailey grin with which he comments on something that science still regards as uncertain or obscure, and hear him declare to the jury that, in the present state of medical knowledge, there is not a man in court might not be indicted for having handed the salt or the mustard to his neighbour!"' Detection of the Adulteration of Arrowroot with Potato or Corn Starch.-According to J. F. Albers (Arch. de Pharm.), this is effected with certainty by means of their behaviour towards hydrochloric acid. When one part arrowroot is shaken with three parts of a mixture of two parts hydrochloric acid of 1*12 sp. gr. and one part of distilled water, at ordinary temperatures, for about three minutes, no reaction is observable. But should corn starch be subjected to this treatment, it becomes changed into a gelatinous, translucent, and finally into way, with the production of an easily recognised and characteristic smell. If a mixture of arrowroot with one or more of these substances is to be dealt with, the arrowroot is to be separated by treating the whole for two to three hours with the hydrochloric acid, by which the arrowroot becomes soluble, and may be filtered from the remaining softish mass, which when washed, dried in the air, and weighed, shows by the loss in weight the amount of arrowroot present. a semi-fluid mass. Potato starch behaves in the same Hugo Levinstein, examined by Mr. Aston: [In order to get the whole of the evidence into this volume, we are compelled to omit all but that part of the defendant's evidence which is most important to our readers.] Has been a maker of aniline and other colours for some years. Is not a scientific chemist; employed chemists. IIad tried Girard's process at Milan, but never succeeded in getting a good colour by means of it. In his own process uses the base rosaniline, sometimes, also, hydrochlorate of rosaniline. In both cases he mixes acetic acid in the vessel. Does not add commercial aniline, but uses the waste product which distils over in making magenta red. This waste product will not make red aniline dye; does not give a trace of red. It is not the form in which aniline is sold. Aniline of commerce will make red aniline dye. Did use a small proportion of benzoic acid, but does not now. Uses acetate of soda and glacial acetic acid to form the melt. The proportion of glacial acetic acid was onefourth the weight of the red aniline base. Heated, according to the proportion of acetate of soda, from half an hour to an hour. Gets in this way a perfect blue, which may be purified by sulphuric or hydrochloric acid. Sells it the Office, 1, Wine Office Court, Fleet Street, London, E.C. Private impure in England. Does not use hydrochloric acid in England. Uses sulphuric acid to precipitate the colour, and then boils with more glacial acetic acid and alcohol. One ounce of the acid to a pint of alcohol. We omit the cross-examination by Mr. Grove, as very little of it bore on the scientific points in dispute, to which our report is confined. Mr. Bagshawe summed up the evidence for the defendant, and was replied to by Mr. Grove. We understood the Vice-Chancellor to express an opinion in favour of the validity of Girard's patent; but he reserved his decision as to the alleged infringement. ANSWERS TO CORRESPONDENTS. In publishing letters from our Correspondents we do not thereby adopt the views of the writers, Our intention to give both sides of a question will frequently oblige us to publish opinions with which we do not agree. All Editorial Communications are to be addressed to the EDITOR, and Advertisements and Business Communications to the PUBLISHER, at letters for the Editor must be so marked. Vol. X. of the CHEMICAL NEWS, containing a copious Index, is now ready, price 10s. 8d., by post, 118. 2d., handsomely bound in cloth, gold lettered. The cases for binding may be obtained at our Office, prico 18. 6d. Subscribers may have their copies bound for 2s. 6d. if sent to our Office, or, if accompanied by a cloth case, for 18. Vols. I. and II. are out of print. All the others are kept in stock. Vol. XI. commences on January 6, 1865, and will be complete in 26 numbers. M. Leduc.-Mr. Solomons, Red Lion Square, London, will furnish it. G., Belfast. It was read before the Royal Dublin Society, and printed by M'Gill, of the Dublin University Press, from whom you will proThe writer is thanked for his suggestion. bably be able to procure it. Mogenta.-The decision has not yet been given. Received.-C. R.; R. T. Clarke. INDEX. ACETIC ether, action of sulph- phosphoric, estimation of, 265 silicic and other colloidal sub- Actonian prize essay, 300 on Schwarz's process for purify- Agriculture, on British, 33 heated, as a substitute for steam Albumen, note on the distribution of, through muscular tissue, 283 of, taken in moderate quanti- Aldehyde, transformation into Algeria, nitrification in, 82 Alkaline nitrates and nitrites, action 25 in cinchona bark, 77 on the assay of, in medicinal ex- Alloxan, on the action of heat on, 121 Allylene, new process for the pre- separation of cerium from, 195 genated water and amylene, 217 fluohydrate of fluoride of potas- Auiline case, Simpson v. Holliday, 48 in varnishes, 74 Anuales de Chimie et de Physique, preservation of 186 phosphorus, a new method of Arsenious and antimonious acids, on, extracted from the tubers Aspirator, a new, 295, 315 tion of dialysis in determining BACTERIA, influence on the animal Baker, W., on the existence of on the occurrence of nickel in Becquerel, M. on the preservation of iron and cast iron in soft on the preservation of iron and Beilstein, M. hydrocarbons of coal Benger, F. B. on the pharmaceuti- cal application of glycerine, 187 on the motions of, on the surface searches on opium and its on formic acid, 201, 258, 274, 285 Bisulphide of napthalin, 259 stone Shoals of the Years 1862- Buxton thermal spring, on the, 179 respiration of flowers, 146 try applied to the arts, 15, 30, gold from auriferous ores, 160 212 Caproic acid, on the synthesis of, Caron, M. cementation of iron by Carpet, a cheap, 118 Carlton Place, Secular School, Glas- Case, a sad, 12 Caseine, or the curd of milk, 113 and a new hydrocarbon of the Cellulose, note on the action of Cerium, on the separation and esti- Charcoal, assay of animal, 166 change, on the rate of, 171 Processes of the British Pharma- copoeia, review, 82 researches in Royal Institution, recent, 111 Society, 24, 33, 216, 240, 288, 302 Chemists and druggists, position Chemistry, Elements of Theoretical A Dictionary of, Watts's, review, 253 Chloroform a test for sugar in Chrysen, on, 243 density of certain minerals, 234 remarks on the parabenzol serios, revision of the mineral phos- Citrate of iron and quinine, on the Clasen, M. on the estimation of tin of rudimentary che- Clausius, M. on the difference be- gen, 73 Coal gas, soda in, 74 volumetric process for estimating, Continental science, 10, 23, 36, 47, Cooking without fire, 288 Copper, alteration in the weight of, Copper, haloid salts of, 178 in the Bath waters, 158 preservation of, in the sea, 35 Corn, on the development of, 237 oil, 240 Coulier, M. on the rings of phos- Crookes, W., FR S. suggestions for, Crystallised arseniates and phos- Cuba, how sparrows found their Cucuyos, phosphorescent light of Curd of milk or casein, 113 Cyanide of potassium, sale of, 204 DALE, R. on the action of baryta on Damour, M. on callais, 296 and M. Deville, on parisite, 91, Dancer, Mr. a new aspirator, 295, 315 lumination, 314 tion of hydrocyanic acid from 194 production of some crystallised and M. Ubaldini, chemical re- erythrite and its derivatives, 202 Deville, M. St Claire, on the dis- De Vry, Dr. J. E. method of de- application of, in determining the Dilysation, case of, 47 Diamonds, on the occurrence of, in Index. Dibbits, Dr. on the spectra of the new properties of, 25 benzol in oil of bitter almonds, 232 Drug Company, Wholesale and Ex- Dublin International Exhibition, Dye for feathers, 240 118 ELECTRIC light, danger in the, 12 ments relating to, 91 of Materia Medica, &e. 238 Equivalent of indium, 84 numbers, numerical relations of, Enamel leather, 38 Erosion of lead by insects, 168 Ethers, on the nature of compound, 271 Ethyl and hydride of methyl, iden- note on valerianate of, 272 the Department of Science and Fatty bodies, on the saponification of, by alkaline sulphides, 35 which have a physiological Solubilities of Chemical Sub- sium, on the employment of, in Forest marble, on the blue colour Forchhammer, Prof. on the consti- tution of sea water at different Formamide, preparation of, by Formic acid, on, 258 234 Gas, passage of, through homo- geneous solid bodies, 57 spectra of the flames of various, Geology, chemical, 19, 43, 66, 78 tographic yellow glass, 252 ammonia on sulpho-chloride of Glucinum, on the quantitative se- in nitric and sulphuric acids, 167 ties of silicic acid, and other dialysis to the investigation of Graphite, origin of, 61 CHEMICAL NEWS, Haselden, M. A. F. on the extracts on extractum krameria, 306 artificially crystals of anastase, Heat, specific, of solid and liquid Heavenly bodies, on the spectra of Heldt, M. W. the passivity of Hensser, M. and M. Clarez on the occurrence of the diamond in of the heavenly bodies, 185, 254 Human breath, a physical analysis Hunt, R. Memoirs of Distinguished new, 192, 216 Hydrocyanic acid from bitter Cas- sava root, 236 researches on, 291 Hydrogen, has each of the four atoms in CH, the same func- 117 Indian ink, substitute for, 180 Great Pyramid, our Inheritance in Indium, 84, 95, 219, 240 the, 252, 296 heat of the combustion of, 258, Hanbury, D. F.L.S. on the botani- synthesis of, 201 Formula, rational of rosaniline, 157 cal origin of gamboge, 294 Indestructible writing, 245 |