CH. IX] CINCHONA AND OTHER DRUGS 105 



the aid of science, taking steps to improve the yield of the 

 alkaloids in the bark by a careful selection. This selection has 

 gone on for a great many years, and the result has been that 

 the best Java barks of Cinchona Ledgeriana now contain as 

 much as 15 17 per cent, of their weight of the drug, while 

 the Ceylon barks rarely exceed 8 per cent. This of course 

 means that a far less quantity of the heavy bark has to be 

 grown and sent to Europe to obtain the same monetary return, 

 and consequently nowadays Java has a practical monopoly of 

 the cinchona market, from which there seems little likelihood 

 of ousting her, though it must be pointed out that the profits 

 in this cultivation are now but small, even in Java. 



The plant is grown from seeds, and forms a small tree 

 which grows best in the mountains of the tropics at elevations 

 of 4000 feet or more, in wet districts. The plants are usually 

 put out at distances of three or four feet, and after three or 

 four years are thinned out. The most usual ways of obtaining 

 the bark are coppicing and shaving. In the former case the 

 trees are cut down, and the stocks are allowed to grow up 

 again. In the latter case the bark is shaved with a spokeshave 

 nearly, but not quite, down to the cambium. If the latter be 

 not injured, the bark will quickly grow again. It is sometimes 

 tied up in moss to encourage renewal. 



The most promising directions in which improvement may 

 be looked for in cinchona cultivation are in the continual im- 

 provement of the barks by selection of the richest in each 

 generation, in green manuring, and in grafting the less hardy 

 species, which also happen to be the richer in alkaloid, upon 

 the more hardy, such as Cinchona succirubra. This is now 

 largely done in Java, with very good results. 



Coca. This plant (Erythroxylon Coca) is also a native of 

 the Andes, and the Indians use the leaves largely as a masti- 

 catory, the chewing of coca leaves enabling them to resist 

 fatigue. In recent years the plant has also come into use 

 in Europe and America, the drug cocaine, obtained from the 

 leaves, proving to be a most valuable local anaesthetic. It has 

 also powerful stimulating properties, and the " cocaine habit," 



