TAPPING 67 



that this residue of latex left in the cut is the salvation 

 of the industry, when the serious injury inflicted on 

 the trees from the constant use of the axe is taken into 

 consideration. 



Experiments carried out in 1913, using a bent gouge 

 instead of the machadinho, showed that a collector could 

 only tap from sixty to seventy trees with two or three 

 cuts regularly each day, or one-half the number possible 

 with the machadinho. It is true that as long as the 

 trees remained healthy and free from bark disease the 

 yield from the herring-bone system was double that 

 obtained by the axe, but in many cases the quality of 

 the latex became thin and the percentage of dry rubber 

 diminished. The natural and probably correct deduc- 

 tion drawn from these results was that the trees were 

 I unable to sustain the additional drain upon their 

 ; resources caused by the greater number of latex cells 

 opened in the length of surface exposed by the gouge, 

 as compared to the triangular incision made by the 

 machadinho. 



Overhead tapping that is, above the reach of a man 

 standing on the ground is practically prohibited in the 

 Madeira districts, and entirely so in the section of the 

 State of Matto Grosso traversed by the Madeira- 

 Marmore Railway. However, it is common practice in 

 the vicinity of the Lower Amazon and its tributaries, 

 on the Purus and Jurua, and in the districts of the upper 

 rivers and their affluents. In many cases, especially 

 on the islands of the delta, the tapping is carried up 

 to a height of 40 feet from the base of the tree. To 

 enable the collector to use his axe and gather the latex, 

 rough platforms are constructed of saplings, a notched 



