Chap. IY. IXDIA-EUBBER TREES. 143 



but at this time, there having been three months of 

 line weather, they were dry throughout, and by the 

 subsidence of the waters placed four or five feet above 

 the level of the river. They are covered with a most 

 luxuriant forest, comprising a large number of india- 

 rubber trees. We found several people encamped 

 here, who were engaged in collecting and preparing 

 the rubber, and thus had an opportunity of observing 

 the process. 



The tree which yields this valuable sap is the 

 Siphonia elastica, a member of the Euphorbiaceous 

 order ; it belongs, therefore, to a gi'oup of plants quite 

 different from that which furnishes the caoutchouc of 

 the East Indies and Africa. This latter is the product 

 of different species of Ficus, and is considered, I 

 believe, in commerce an inferior article to the india- 

 rubber of Para. The Siphonia elastica grows only on 

 the lowlands in the Amazons region ; hitherto the 

 rubber has been collected chiefly in the islands and 

 swampy parts of the mainland within a distance of fifty 

 to a hundred miles to the west of Para ; but there are 

 plenty of untapped trees still growing in the wilds of 

 the Tapajos, Madeira, Jurua, and Jauari, as far as 1800 

 miles from the Atlantic coast. The tree is not remark- 

 able in appearance ; in bark and foliage it is not unlike 

 the European ash ; but the trunk, like that of all 

 forest trees, shoots up to an immense height before 

 throwing off branches. The trees seem to be no man's 

 property hereabout. The people we met with told us 

 they came every year to collect rubber on these islands, 

 as soon as the waters had subsided, namely, in August, 



