294 



THE TROPICAL AGRICULTURIST. 



[October i, 1882. 



yieUlecl by the Japanese plant was ctlnsirlerably m:)re than 

 that yielded by the Euglish plant, and of a very different 

 odoiu". 



Mr. Holmes said that the difference between different 

 varieties of plants was very important. An instance in 

 point was the Japanese peppermiat oil, which he had 

 alluded to, and whith was obtaiiieti, not from Mentha 

 Pijierita but from a variety of Mentha arvensis^ which in 

 England yielded an essential oil that was quite different 

 in taste and odour. Botanists observed but very little 

 difference between the English Mentha artiensis and the 

 variety used in Japan for peppermint oil. In the same 

 way, botanists had classed together a great many aconites 

 in the same group as Aconitum i^aniculatmn, some of which 

 were known to be poisonous, although that species did not 

 appear to be so. It seemed to him that the aconites re- 

 quired examination from a chemical as well as a botanical 

 point of view. A chemical examination might throw con- 

 siderable light on the botanical relationships of different 

 species which were now classed together. He observed that 

 the Pharmacoposia said concerning aconite root " Imported 

 from Germany or cultivated iu Britain." He thought that 

 it would be highly important in the next Pharmacopoaia 

 to omit the words " Imported from Germany," because, 

 until they could be sure that all the German aconite w.is 

 obtained from Aconitum Napellus, they would frequently 

 get varieties of which they knew nothing, and consequently 

 it would be impossible to say whether German aconite 

 contained aconitine in various pcoportious or some other 

 alkaloid, which might not possess the same properties as 

 aconitine. The specimen of henbane root referred to by 

 Mr. Cleaver was the only one received from Mr. Squire, 

 and it had not been examined. 



The President said that he beUeved that the only mode 

 of determining whether a tincture of hyoscyamus had 

 been made from the biennial henbane or not was the 

 use of the spectroscope, as was pointed out by Mr. Stoddart 

 some years ago. At the Swansea Conference, he (the 

 President) had read a note on some henbane from India, 

 and Mr. Umney then made the remark that on the 

 continent hyoscyamine was prepared from the annual 

 henbane. 



Dr. Symes, on behalf of Mr. AVilliams, who was absent 

 in consequence of ill-health, brought before the meeting 

 some observations on chiuoline. He said that this was 

 a body which was exciting attention iu the medical world, 

 and therefore had an interest for pharmacists. Mr. "Williams 

 had sent some very nice specimens of chinoline, pure 

 and tartrate, artificial and otherwise. Chinoline had the 

 chemical formula of C9H,N. It was prepared originally 

 some few years ago from cinchonine and quinine, and was 

 said to be also prepared from strychuiue. Cinchonine 

 was, however, its principal source, and it was prepared 

 by heating that alkaloid in a solution of caustic soda. 

 In fact, the cinchonine underwent destructive distillation 

 at a high temperature, the result being a very dark red 

 oily-looking liquid, which had a most unpleasant odour, 

 and was very impure. Professor Greville Williams devoted 

 considerable attention to this body. Upon being redistilled, 

 it produced a brownish liquid, which was still impure, and 

 a tarlike residue. Professor Greville Williams found five 

 or six other basic bodies present iu this liquid, in addition 

 to chinoline. He came to the conclusion that the best 

 means of obtaining pure chinoline was to produce the 

 chromate. Latterly, however, chinoline had been produced 

 synthetically, and "it was this fact, probably, which had 

 caused some amount of inquiry into its nature. The 

 original use to which this body, as prepared from cin- 

 chonine, was devoted was the production of cyauine, a 

 blue colouring matter, by heating it with iodide of amyl 

 and potash. Chinoline was produced synthetically by the 

 action of caustic potash unon a mixture of glycerine and 

 aniline. He did not know that there was any published 

 description of the method ; but he believed that it was 

 patente I in Germany and possibly so in England. The 

 Germans found that the b'st m.^ans of oHtainin,ir pure 

 chinoline was by the production of a tartrate. They found 

 that on treating the chmoiiue with an excess of tartaric 

 acid and boiling water, the chinoline tarti-at? crystallized 

 out. and many of the impurities were separatotl iu the 

 mother liquor. The present specimen had been obtained 

 by forming an acid tartrate in boiliug water, and allow- 



ing it to cool and crystallize in this way. The process 

 had been repeated three times to obtain a comparatively 

 pure salt. When it was wished to obtain a pure chinoline, 

 the tartrate was decomposed with caustic soda and agitated 

 with benzine. This was the method of purification which 

 had been adopted by Mr. Williams himself. The benzine 

 dissolved out the pure chinoline, and left behind some 

 trace of impurity which still existed in the tartrate. The 

 solution in benzine was then evaporated until the smell 

 of benzine had disappeared. The liquid was then distilled, 

 and about an eighth or a ninth of the liquid came over 

 at a temperature below 238 * 0. That was not pure chinol- 

 ine, but the pure chinoline would distil at that temperature. 

 There was a specimen of it present, from which it would 

 be seen to be an oil-like liquid having a pale brownish 

 tint. The artificial had very much the same appearance. 

 From chinohne (as had been stated) cyanine had been 

 prepared, by treating the chiuoline with iodide of amyl. 

 The blue colour was developed on the addition of caustic 

 soda. If some chinoline were put into a test tube and 

 held over the flame of a spirit lamp, it darkened after 

 a time, and ultimately formed a red resinous body; the 

 addition of caustic soda then developed the blue colour. 

 The artificial chinoline treated in this way yielded a 

 brownish and not a blue colom-. Mr. AVilliams particularly 

 wished him to say that he did not put this forward as 

 any evidence of impurity in the artificial chinoline. Although 

 chemically the same as the natural chinoline, it would 

 appear as though there must be some different arrangement 

 of the molecules, or difference in the physical constitution. 

 It was known that leucoline, having the same chemical 

 formula as chinoline and obtained from coal tar, does 

 not yield cyanine. The tartrate of chinoline was the 

 substance which was used internally for medicinal purposes. 

 It was supposed to be a cheap substitute for quinine, 

 but its taste was rather unpleasant. He was not prepared 

 to say how far it fulfilled this purpose medicinally. He 

 had been informed that the pure chinoline hed been used 

 for the purpose of producing local anaesthesia. 



Mr. Passmore, in reply to Dr. Symes's query, said that 

 a description of the process for the synthetic preparation 

 of chinoline had been pnbhshed by Herr Skraup in the 

 Austrian Monatshefte far Chemie about twelve mouths pre- 

 viously. Herr Skraup preferred to act with an alkali upon 

 a mixture of nitrobeuzioe and aniline in the presence of 

 glycerine, for although either nitrobenzine or aniline would 

 yield chinoline, the one by the elimination of hydrogen, 

 and the other of oxygen, the yield from a mixture of 

 the two appeared to be more favourable. From the de- 

 scription of the process he should gather that very great 

 difficulty was experienced in the purification of the pro- 

 duct, the chinoline being produced in a mixture of similar 

 bodies, rather thau as a definite body in a state aporoxim- 

 ating to purity. 



Mr. Robbins said that he was with Dr. Symes when 

 Mr. Williams explained the process to him, and they might 

 congratulate Dr. Symes on the very lucid way in which 

 he had made the communication. Mr. Williams had been 

 prepared to perform the experiments necessary for illus- 

 trating the process, and a number of other experiments 

 of an interesting character. He (Mr. Robbins) thought 

 that this was one of the most interesting subjects which 

 had been before these meetings for some time. It was 

 a curious fact that the artificial chinoline was not exactly 

 the same as the natural, for, although they were unable 

 to distinguish the two kinds in many ways, still the 

 artificial would not yield cyanine. This showed that there 

 was a difference in the arrangement of the elements. As 

 to the use of chinoline as a medicine, it was a nice- 

 looking white crystalline body, to the appearance of which 

 no one would object, but its taste was so excessively 

 disagreeable, that it must have many advantages which 

 quinine did not possess, if it was to supersede that drug. 

 The taste of quinine, although bitter, was yet pleasant 

 ia comparison. 



Mr. Oarteighe said that several of the specimens of 

 chinoline which he had examined, though not in a very 

 detailed way, had given him much the same impression 

 as that recorded by Mr. Ekin in a .short note in the 

 Journal a few weeks ago. Because chinoline was pro- 

 duced artificially in a cheap way and possessed certain 

 crystalline characters, and was regarded in the report of 



