216 



Selections. 



[NO. 2, NEW SERIES, 



« The details in the process of drying also vary slightly in the 

 two cases ; the thinnest pieces of hark from the branches or small 

 trunks, intended to make the quilled cinchona, are simply exposed 

 to the sun's rays, and of themselves take the desired form, which is 

 that of a hollow cylinder ; but the bark taken from large trunks, 

 which is to constitute the flat cinchona, or, as it is called, tabla or 

 plancha, must necessarily undergo a certain degree of pressure dur- 

 ing the process of desiccation, without which it would become mis- 

 shapen, or take a cylindrical form as in the preceding case. To 

 effect this, after first exposing the pieces of bark to the sun, they 

 are placed one on the other in crossed squares, in a similar man- 

 ner to that practised in timber-yards in the arrangement of the 

 planks of wood, and on the top of this pile a heavy weight is 

 placed. This process is repeated for several days until the bark is 

 completely dried. 



" The above process is that most commonly adopted in preparing 

 the cinchonas ; but it will be easily comprehended that this must 

 vary, in some degree, according to the locality, or the nature of 

 the tree operated upon. In many places the bark is not pressed 

 at all, or but imperfectly so, and it is then generally out of form or 

 slightly curled. The peridermis is often but partially removed, or 

 simply scraped. Finally, whether it be accidental, or whether it 

 be done with the view of augmenting the weight, there frequently 

 remains a certain quantity of moisture in the bark, which greatly 

 deteriorates it. It thus appears that cinchonas which would have 

 presented the same characters if similarly prepared, may, accord- 

 ing to the circumstances, vary very greatly. In any of these cases 

 the labour of the cascarillero is by no means ended, even when he 



cut off the branches, taking care to leave the terminal branch ; but those whom 

 I have known have always candidly confessed that tliey found the most simple 

 method to be that of cutting the trees down, and this, I believe, has been the 

 uniform practice Thousands of quintals of cinchona bark have been thus left to 

 perish in the forests ; and it has only been since the inutility of the practice has 

 been proved by chemical analysis that it has been discontinued. It is not to be 

 considered, however, that the bark of old trees contains as much of the active 

 principle as those which have only arrived at maturity. There are limits between 

 which all are good ; indeed, none ought to be rejected. 



