.^70 CHIXCHOXA OR PERUVIAN BARK. 



Chinchonine is of less strength than quinine, and is used in 

 mild cases of intermittent fever ; but in severe cases, the use 

 of quinine is absolutel}^ necessary. Since the discovery of 

 the medicinal properties of this bark, it has proved an in- 

 estimable blessing to the human race. For many years the 

 bark itself was used as a febrifuge ; but quinine, which is ex- 

 tracted from it, is of still greater value in curing or prevent- 

 ing ague. On various occasions it has rendered great service 

 by preserving the health of troops. Many lives were saved 

 by it in the disastrous Walcheren expedition. In India it is 

 now universally used Avith the same beneficial effect ; and 

 several African explorers have been enabled to prosecute their 

 journeys through pestiferous regions by its frequent usa 

 Dr. Livingstone, among others, speaks of it as the chief 

 remedy he has employed when attacked by sickness on his 

 journeys. 



Most of the Chinchonae, when growing in good soil, and under 

 favourable circumstances, become large forest trees. When 

 crowded, they frequently run up to a great height without a 

 branch ; while at the upper limit of their zone, they become 

 mere shrubs. 



There are numerous species of chinchona, producing bark of 

 greatly different values. There are upwards of nineteen dif- 

 ferent species of the true Chinchonae, and upwards of seventy 

 once received as such, though now considered of no com- 

 mercial value. The three characteristics by which the true 

 chinchona may be known are — the presence of curly hairs 

 bordering the lacinise of the corolla ; the peculiar mode of 

 dehiscence of the capsule from below upwards ; and the 

 little pits at the axils of the veins on the under sides of the 

 leaves. The leaves are of a great variety of shapes and 



