180 THE AFRICAN RUBBER TREE 



(&) A tree tapped in 1908 by the half-herringbone 

 system was tapped again on another side : 



oz. 



Yield of fresh rubber in 1908 . . .2 

 „ „ ,, 1909 . . • I2 



(c) Two trees tapped in 1908 by the half-herringbone 

 system were tapped again by making new lateral cuts 

 below the previous incisions : 



oz. 

 Yield of fresh rubber per tree in 1908 . . 2 



,, ,, ,, J, XV\JV . . 4 



{d) Two trees were tapped by the half-herringbone 

 system, the lateral incisions bemg 12 in. apart in one case 

 and 6 in. in the other. 



Yield of rubber from tree 24 in. in girth with lateral 



incisions 12 in. apart was If oz. 

 Yield of rubber from tree 22 in. in guih with lateral 

 incisions 6 in. apart was 1| oz. 

 (e) A tree, 24 in. in girth, was tapped by the spiral 

 system, the spirals being 1 ft. apart. After two days a 

 new spiral cut was made between the first incisions : 



Rubber from 1st tapping . . . -41 



„ 2nd „ .... I 



A tree 12 in. in girth tapped by the spiral system gave 

 I oz. of rubber. 



(/) A tree, 24 in. in girth, was tapped by making four 

 vertical parallel cuts 16 ft. high ; after two days four 

 other cuts were made between the first incisions. 



Rubber from 1st tapping . . . .2^ 



„ 2nd „ .... li 



(g) A tree, 20 in. in girth, was tapped by making four 

 vertical parallel cuts to a height of 8 ft. ; when the flow 

 of latex ceased the cuts were continued to a height of 

 16 ft. 



