millions) by additional application of another equal quantity of labor on the same land in each period, then at the end of one hundred years there would be the disproportion of one hundred and seventy-six millions of people, with subsistence for only fifty-five millions. Of course, this is prevented either by checking population to the amount of the subsistence; by sending off the surplus population; or by bringing in food from new lands.
In the United States to 1860 population has doubled itself about every twenty years, while in France there is practically no increase of population. It is stated that