206 THE AFRICAN RUBBER VINES 



beating of the bark necessitated 32 hours' labour, making 

 a total of 41 hours. This labour was valued at fr. r64, 

 and the cost of collecting a kUogram (2-2 lb.) of rubber 

 on this basis would be fr. r88. 



In another instance a ClitaTidra Arnoldiana vme fur- 

 nished 851 grams of rubber, of which 615 grams were 

 obtained by the first operation, 200 grams by the second, 

 and 36 grams by the third (see p. 203). Three men 

 worked for 5 hoiu-s in obtaining the 615 grams of rubber ; 

 two men for 4 hours in obtaining the 200 grams ; and 

 two men for 3 hours in obtaining the 36 grtims. This 

 represents a total of 29 hom-s' labour, and on this basis 

 it was estimated that the cost of collection of a kilogram 

 of the rubber would be about fr. 1*40. 



Baudon has given the following data regarding the 

 time taken by a native in the French Congo to treat 

 20 kilograms of the rhizomes of Landolphia Thollonii : 



Hours 



Total . . . .36 



In this experiment the native, by the expenditure of 

 thirty-six hours of labour, obtained ri20 kUogram of 

 marketable rubber. 



Improved Methods of Exploiting Rubber Vines. — ^luch 

 discussion has taken place on the question of the 

 best method of exploiting rubber vines, and many at- 

 tempts have been made to improve the native methods 

 of collection so as to prevent the destruction of the plants. 

 The problem, however, presents many difficulties, prin- 

 cipally owing to the habit of growth of the vines which 

 renders them much more difficult to deal with than 

 rubber trees, and no general agreement as to the most 

 satisfactory method of treatment has been reached. 



The two principal systems employed by the natives 

 have been already referred to, viz. : (1) tapping the vines 



