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XX. — On the Volatile Bases produced by Destructive Distillation of Cinchonine. 

 By C. Greville Williams, Assistant to Dr Anderson, University of Glasgow. 



(Read 16th April 1855.) 



The history of the organic bases has now become as ardent an object of study 

 among chemists as that of the as yet far more numerous group of acids ; and it 

 is generally admitted that the information obtained has been no less important 

 and interesting. Of all organic alkaloids, those of opium and the cinchona barks 

 doubtless occupy the first rank, whether we regard their value as remedial agents, 

 or the remarkable facts which have been ascertained connected with their atomic 

 relations, and the influence exerted by the latter, upon the theory of the science. 



It has long been known, that many of these fixed oxidized alkaloids may, by 

 destructive distillation and analogous processes, be made to yield an entirely dif- 

 ferent, and no less interesting class, distinguished from the first by their volati- 

 lity, and the absence of oxygen. 



None of the bases produced by such decompositions have attracted more 

 attention than chinoline ; not that, like aniline, it has yielded any compounds 

 which, from their perfect analogy with those of ammonia, the beauty of their 

 salts, or any peculiarities in their coloured reactions, are interesting per se ; on 

 the contrary, the highness of its atomic weight and boiling point, the small 

 tendency of its salts to form well-defined crystals, and the absence of any spe- 

 cialties in its behaviour with reagents, make it entirely dependent on its stochio- 

 metrical relations, and on its supposed intimate connection with quinine, cin- 

 chonine, and strychnine, for the interest it possesses. While chemists believed 

 that those alkaloids, minus a certain amount of hydrogen and carbonic acid, 

 yielded chinoline, a very simple relation appeared to exist between them, a 

 simplicity that gave interest to the subject; but when it was announced that ( 

 the leukoline of coal tar was identical with chinoline ; and still more, that the 

 product of the action of iodide of methyl on leukol, when converted into a 

 hydrated oxide was isomeric with quinine, if not the same substance, many 

 were found who believed that the artificial production of the chinchona alkaloids 

 would soon become a common process. But the evidence of the identity of leukol 

 with chinoline was contradictory ; Hofmann first asserted, in his Researches upon 

 the Bases of Coal Naphtha, that their behaviour with chromic acid demonstrated 

 their dissimilarity, while subsequently,* Liebig announced, upon the authority of 



* Chemical Gazette, vol. iii., p. 251, 1845. Proceedings of Chem. Soc, April 7, 1845. 

 VOL. XXI. PART II. 4 



