NAT. ORDER. CI.NCHONACE^. 29 



stitution. The first class precipitates astringents, but not gelatine ; 

 the second precifiitates gelatine, but not astringents ; the third pre- 

 cipitates both gelatine and astringents ; there are also some barks 

 which precipitate neither gelatine nor astringents ; but they are 

 not considered by botanists as properly belonging to the genus cin- 

 chona. Each of the three first classes ai'e said to be capable of 

 curinof intermittants. 



It had been long a desideratum among pharmaceutical chem- 

 ists to discover in the barks the particular substance to which the 

 febrifying proj^erty might be ascribed ; and in pursuit of this object, 

 Laubert of Paris, Strenss of Moscow, and Gomez of Lisbon, pub- 

 lished, about the same time, the result of their observation ; but the 

 French chemists were most successful ; they obtained a substance, 

 which they recognised as that to which M. Gomez had given the 

 name of cinchonine, and they evidently proved more successful in 

 arriving at the correct properties of this most valuable plant. The 

 cinchonine was obtained by operating on the cinchona condamina, or 

 grey hark of the French botanists. The cinchona cordifolia (the cin- 

 chona officinalis of our Colleges, the yellow-bark of the French) was 

 next subject to analysis, and from this was obtained an alkali, in 

 many points resembling the cinchonine, but still differing in many 

 important ones, sufficiently to prevent their being confounded : this 

 alkali was called Quinine, The examination of the red-hark (cin- 

 chona ohlongifolia) followed ; and "it was an interesting question," 

 says M. Magendie, " to determine whether this species, considered 

 by many medical men as eminently febrifuge, contained quinine cin- 

 chonine, or a third variety of alkali. The result was, that they ob- 

 tained, not only a treble quantity of cinchonine, (in all respects like 

 that obtained from the grey-hark) but also nearly twice as much 

 quinine as the same quantity of yellow bark had yielded. From 

 ulterior experiments, made on large masses, it appears that quinine 

 and cinchonine exist in all three species of bark, but the cinchonine 

 is in greater quantity than the quinine in the grey-bark, while in 

 the yellow-bark, the quinine greatly predominates." 



