502 TRUNK-BARK. Chap. XX^ 



We now come to the otlier alternative, that of raising 

 chinchonae in their shrubby form, on plantations in ( 

 clearings, with plenty of fresh air and sunshine. It is 

 system of cultivation which I, in common with Mr. Ho"\ 

 and Mr. Mc Ivor, consider to be the most likely to lea 

 successful results, because it is the only one by which vi 

 nerative harvests of bark can be obtained year by a 

 without injuring the plants. 



Two questions require consideration before adopting 

 method : first, whetlier the chinchonae in their shrubby : 

 will yield a sufficient annual supply of febrifugal alkaloi( 

 make the cultivation remunerative ; and secondly, wheth 

 will be possible to take the required quantity of bark e 

 year, without checking the growth of the trees. 



The trunk or tabla bark naturally yields a much larger 

 centage of alkaloids than tlie canuto or small bark of 

 branches ; but as a supply of the former could onlj 

 obtained once in forty years, and then at the cost of desi 

 ing the plantations, while the latter will yield an an 

 harvest without any injury to the trees, this point is n 

 much consequence.*^ 



The fact is that very little tabla or trunk-bark comes : 

 South America, and that nearly the entire bark trac 

 supplied by quill-bark from the branches of shrubs. S 

 Calisaya bark from Bolivia, some " red bark," and " "V 

 coast Carthagena," from the trunks of C. Paltan, arriv 

 the form of large slabs of tabla-haxk ; but a great deal o: 

 Calisaya and succirubra bark, the whole of the " crown-bj 

 from Loxa, and all bark from other quarters, is found on! 

 the form of quills from small branches. I have meas 



^ In quills from large branches there I but this diminislies in quantit 

 is m(jre alkaloid than in the smaller deteriorates in quality in the hi 

 branches: in tlie bark of the trunk the roots. — Hoicard. 

 the proportion is still further increased, 



