Ever since the great mechanical inventions of Watt, Arkwright, and their contemporaries, the return to labor has probably increased as fast as the population; and would even have outstripped it, if that very augmentation of return had not called forth an additional portion of the inherent power of multiplication in the human species. During the twenty or thirty years last elapsed, so rapid has been the extension of improved processes of agriculture [in England], that even the land yields a greater produce in proportion to the labor employed; the average price of corn had become decidedly lower, even before the repeal of the corn laws had so materially lightened, for the time being, the pressure of population upon production. But though improvement may during a certain space of time keep up with, or even surpass, the actual increase of population, it assuredly never comes up to the rate of increase of which population is capable: and nothing could have prevented a general deterioration in the condition of the human race, were it not that population has in fact been restrained. Had it been restrained still more, and the same improvements taken place, there would have been a larger dividend than there now is, for the nation or the species at large. The new ground wrung from nature by the improvements would not have been all tied up in the support of mere numbers. Though the gross produce would not have been so great, there would have been a greater produce per head of the population. § 3. Necessity of Restraining Population not superseded by Free Trade in Food. When the growth of numbers outstrips the progress of improvement, and a country is driven to obtain the means of subsistence on terms more and more unfavorable, by the inability of its land to meet additional demands except on more onerous conditions, there are two expedients, by which it may hope to mitigate that disagreeable necessity, even though no change should take place in the habits of the people with respect to their rate of increase. One of these expedients is the importation of food from abroad. The other is emigration.