732 OTHER MINOR PRODUCE FROM TREES. 



Caoutchouc trees show great variations in form and size. 

 The llt'i'ca and Fiais clastica are huge trees, while the Landol- 

 phias of W. Africa are lianes, and the rubbers of the Congo 

 State are obtained from the rhizomes, or underground sterns, 

 of plants that grow only one or two feet above the sand. The 

 best rubber is obtained from the Hevea in the Amazon valley, 

 and is known as Para rubber. Its composition is as follows : 



Caoutchouc 31 '70 per cent. 



Albumen T90 ,, 



Other nitrogenous and saline matters 10*03 

 Water 56'37 



The best quality of Para rubber is smoked carefully with 

 palm nuts, before export. Kubber is prepared also most 

 carefully in the Congo State, and is consequently in great 

 demand. 



Terry says, that, leaving out the wasteful destruction of 

 trees by felling, the following points in the preparation of 

 rubber call for special attention : 



1. Careful tapping so that other juices of the tree may not 

 be mixed with the latex. 



2. Avoidance of mixing latex from several species so as 

 to increase bulk. 



3. Removal or sterilisation of fermentible albuminous 

 matter. 



The raw rubber production of the world for 1906 has been 

 calculated at 65,000 tons, of which 41,000 come from tropical 

 America, 22,000 from Africa and 2,000 from Asia. It is a 

 characteristic of the tropics, that frequently plants from all 

 tropical districts can be planted successfully in any tropical 

 district. As extensive plantations of Hevea and other rubber- 

 plants have recently been made in Ceylon and in the Malay 

 peninsula and in Islands, the supply of caoutchouc from 

 Asia will become gradually more important than it is at 

 present. 



Gutta-percha is the produce of the sapotaceous trees. 

 Dichopsis Gutta and D. oblonyifolium of the Malay peninsula, 

 and of Borneo, Sumatra, Java, Celebes and the Philippine 

 islands. Gamble states that the method of production has 



