4 1 6 Voyage of the Novara. 



and in the interim the most decided steps were taken to check 

 the superfluous, indeed dangerous, zeal of the Cascarilleros 

 in the collection of the bark. 



While I was in Java chemical experiments had begun 

 to be made with the bark of tlie young China trees, and 

 from the fact that the valuable alkaloid was not found in 

 these, it was hastily inferred that the bark of the trees grown 

 in their adopted country had, owing to the change effected 

 in climatic and other conditions, been deprived of the 

 principle that made them most valuable in their native 

 land. But researches made in South America have satisfied 

 me, that even in the indigenous forests of Cinchona, the 

 active principle quinine is only found in the bark of older 

 trees, and that its quantity is perceptibly affected by the 

 age of the tree, the finest quinine being obtained in largest 

 quantities from trees upwards of fifty years old. To ignorance 

 of this peculiarity must also be attributed in all probability 

 the fact that, at the period of the Spanish rule, the China 

 collectors or hunters ( Cazadores de Quina) used to fell annually 

 800 or 900 young trees of from four to seven years old, to get 

 at the 110 cwts. of fever-bark, which, intended exclusively 

 for the use of the royal house, were shipped every year firom 

 Pa'ita, and thence round the Horn to Cadiz.* 



So, too, with respect to the quantities annually exported at 

 present from Bolivia and Peru, and used in European stores, 

 there remain serious errors to correct, prevalent even among 



* See Humboldt's Ansichten der Natur. Third edition. 1849. Vol. ii. p. 319. 



