Along the sea coast, which would naturally be first inhabited, the period of doubling was about thirty-five years; and in some of the maritime towns, the population was absolutely at a stand.
(In instances of this kind the powers of the earth appear to be fully equal to answer it the demands for food that can be made upon it by man.

But we should be led into an error if we were thence to suppose that population and food ever really increase in the same ratio.

The one is still a geometrical and the other an arithmetical ratio, that is, one increases by multiplication, and the other by addition.

Where there are few people, and a great quantity of fertile land, the power of the earth to afford a yearly increase of food may be compared to a great reservoir of water, supplied by a moderate stream.

The faster population increases, the more help will be got to draw off the water, and consequently an increasing quantity will be taken every year.