date; gardens in north africa (see; page; 291) 
which remains unutihzed. You have 
all noticed how rapidly the population 
of the globe has expanded and how 
rapidly it continues to expand, and how 
it looks as if before very long, within the 
course of a century or two, there will 
hardly be upon many parts of the world 
comfortable standing room left for the 
population. 
THE vast unexplored REGIONS OE 
SOUTH AMERICA 
It therefore becomes of greatest im- 
portance to ascertain what regions can 
be made available for producing food 
and for the habitation of man that have 
not been touched as yet. The largest of 
those, I suppose, is to be found in the 
vast central area of South America, 
which consists of the basin of the great 
River Amazon and the basin of the 
Purana and other tributaries of the Rio 
de La Plata. You have there a region to 
be measured by many thousands of 
square miles, which is at present in- 
habited only by a few wandering Indian 
tribes, most of them in the very lowest 
stage of savagery. Latterly the bands 
of rubber gatherers have been pene- 
trating into some of the districts, and it 
278 
