130 SELECT PLANTS FOR INDUSTRIAL CULTURE 



and by the portion, insoluble in alcohol, being of a pulveru- 

 lent instead of a viscid character. The mode of exsiccation 

 affects much the properties of the product. 



Ficus Cunningham!, Miquel. 



Queensland, in the eastern dense forest regions. Mr. O' Shanesy 

 designates this as a tree of sometimes monstrous growth, the 

 large spreading branches sending down roots, which take firm 

 hold of the ground. One tree measured was 38 feet in circum- 

 ference at 2 feet from the ground, the roots forming wall- 

 like abutments, some of which extended 20 feet from the tree. 

 Several persons could conceal themselves in the large crevices 

 of the trunk, while the main branches stretched across a space 

 of about 100 feet. A kind of caoutchouc can be obtained from 

 this tree. A still more gigantic Fig Tree of Queensland is F. 

 colossea (F. v. M.), but it may not be equally hardy, not 

 advancing naturally to extra-tropical latitudes. This reminds 

 of the great Council Tree, F. altissima. 



Ficus elastica, Roxburgh.* 



Upper India, to the Chinese boundary known as far as 

 28 30' north latitude. A large tree, yielding its milk sap 

 copiously for caoutchouc, i. e. } the kind called Assam Rubber. 

 Roxburgh ascertained 60 years ago that India-rubber could be 

 dissolved in cajaput oil (so similar to eucalyptus oil), and that 

 the sap yielded about one-third of its weight caoutchouc. This 

 tree is not of quick growth in the changeable and often dry 

 clime of Melbourne, but there is every prospect that it would 

 advance rather rapidly in any unutilised humid forest gullies, 

 and that copious plantations of it there would call forth a new 

 local industry. This tree has grown in Assam to 112 feet 

 with 100 aerial roots in 32 years (Markham). The import 

 of all kinds of caoutchouc into Great Britain during 1874 

 amounted to 129,168 cwt., worth 1,326,605. Markham and 

 Collins pronounce the caoutchouc of F. elastica not quite so 

 valuable as that of the Heveas and Castilloas of South America. 

 Heat and atmospheric moisture greatly promote the growth of 

 F. elastica. Like most other Fig Trees it is easily raised from 

 seed. A tree of F. elastica is tapped in Assam when 25 years 

 old. After 50 years the yield is about 40 Ibs. of caoutchouc 

 every third year (Markham and Collins). Mr. S. Kurz states 

 that F. laccifera (Roxburgh) from Silhet is also a caoutchouc 

 Fig Tree, and that both this and F. elastica yield most in a 

 ferruginous clay soil on a rocky substratum ; further, that 

 both can bear dryness, but like shade in youth. Several other 

 species of tropical Figs, American as well as Asiatic, are known 



