TROPICAL EXPLOITATION 77 
land near to the mouth of the river, an enormous area. 
But the labour problem is the great difficulty. 
This digression upon the economic conditions of the 
Amazon valley-has been introduced to show the kind 
of problem which is involved in dealing with tropical 
exploitation. But the same kind of problem turns up 
when we come to deal with the opening up of any 
of the British tropical colonies. Take, for example, 
Guiana, contiguous to Brazil, and just as rich by nature ; 
is it to be slowly populated by British Indian coolies 
growing rice, as is at present happening, or is it to be 
exploited more rapidly and completely in some other 
way¢ The question is political, as is also the question 
as to whether we should use the African colonies for 
growing large quantities of cotton, though Brazil is 
better suited to that crop, and has a much larger area 
available. But if we did not possess a large area yield- 
ing cotton, we might as an empire be at any time at the 
mercy of outsiders, and so it seems advisable to sacrifice 
some agricultural efficiency to political considerations. 
All these things, one may perceive, are at present 
much more questions of finance, labour, or politics, 
than of scientific agriculture properly so-called. 
To return to rubber and the measures being taken in 
Brazil to meet the competition of tropical Asia. One 
of the most obvious would seem to be to introduce the 
use of the tapping knife employed in the East, instead 
of the machadinho (little hatchet) at present employed, 
and which gradually covers the tree with awkward scars. 
This seemed so obvious that it was tried on one or two 
places with bad results. In the damp air of the Amazon 
valley, the cuts became perfect hotbeds of fungus 
