CHAPTER XIII 



INDIARUBBER, GUTTAPERCHA, AND CAMPHOR 



Indiarubber. This is one of the indispensables of modern 

 times, and there is now an enormous trade in it, some 100,000 

 tons being annually consumed. The supply is almost entirely 

 from the tropics, and the demand is constantly increasing. 

 Until quite recently the supply was all from wild plants, 

 usually of forest origin. By far the most important of these is 

 the so-called Para rubber, Hevea brasiliensis, the source of the 

 finest Brazilian rubber; other species of Hevea are also em- 

 ployed. African rubbers are derived from various species of 

 Landolphia and other genera; Lagos rubber from Funtumia 

 elastica; Borneo rubber from Willughbeia edulis; Ceara or 

 Mani9oba rubber a very important kind from Manihot Gla- 

 ziovii, and to a less extent from M. piauhyensis, M. dichotoma, 

 and other species ; Central American and Mexican rubbers, as 

 well as the caucho of the Amazon, which comes mainly from 

 the upper parts of the valleys, from Castilloa elastica and other 

 species; Guayule rubber from Parthenium argentatum ; India 

 rubber from Ficus elastica ; Mangabeira rubber from Hancornia 

 speciosa', and there are several more. The most important, 

 next to the Para rubber, are the Africans, Guayule, and Ceara. 



The rubber is obtained in various ways, but in general by 

 bleeding the stem with an axe or other coarse tool, and collect- 

 ing and coagulating the milk or latex which flows from the 

 wounds. In many countries the tree itself is destroyed in this 

 process, and in all cases it is very injurious. The natural result 

 is that the trees are becoming more and more scarce, and the 

 trade in wild rubber from India, from much of Africa, and else- 

 where, has very largely decreased. Even in Brazil, whence the 



