THE WORLD’S CEREAL AND FOOD-CROPS 47 
populations throws light upon the world-possibilities 
of population generally, and upon the general issues 
of the future. We shall review, therefore, the popu- 
lation-growth between 1906 and 1911. 
For the quinquennium mentioned France was grow- 
ing at a rate which would double its population only 
in 436 years, while Canada’s rate of growth would 
double it in 23% years. From 1790 to 1860 the 
population of the United States grew at a rate which 
would double it in less than this, viz., in a little over 
22 years, a rate which Australia slightly surpassed in 
the quinquennium 1887 to 1891 inclusive, her increase- 
rate being then 3-06 per annum. The rates for 
different countries are given in the table hereunder, 
and the number of years requisite for the populations 
to double, at such rates. 
Growth of Populations between 1906 and 1911 
Rates per 1000 of population, and years necessary to double 
Country. Rate. Years. Country. Rate. Years. 
France 1-€ 426 Switzerland . 12:1 57% 
Jamaica 2-¢ 248 Netherlands . 12:2 57 
Scotland 5-5 126 Denmark . 12:6 55% 
Norway 6-6 105 Germany 13-6 51 
Belgium 6.9 1or Finland 143 49 
Italy . 3-0 87 Rumania . 148 (7 
Sweden 3:4 83 Servia . . I5'5 45 
Hungary . 8+ 83 Chile . . 156 45 
Austria . 84 8i United States 18-2 38% 
England & W. 10:4 67 Australia . 203 34% 
Japan . 108 64% New Zealand 256 27% 
Wd. Average 11:6 60-. Canada . 298 23% 
Ceylon . 12:0 58 Simple Averagerz:3 57 
We have already dealt with the significance of various 
rates of increase, and the further elaboration of this