Let us suppose land of diminishing qualities. The best would naturally be settled first, and as population increased production would take in the next lower quality, and so on. But, as the increase of population, by permitting greater economies, adds to the effectiveness of labor, the cause which brought each quality of land successively into cultivation would at the same time increase the amount of wealth that the same quality of labor could produce from it. But it would also do more than this—it would increase the power of producing wealth on all the superior lands already in cultivation. If the relations of quantity and quality were such that increasing population added to the effectiveness of labor faster than it compelled a resort to less productive qualities of land, though the margin of cultivation would fall and rent would rise, the minimum return to labor would increase. That is to say, though wages as a proportion would fall, wages as a quantity would rise. The average production of wealth would increase. If the relations were such that the increasing effectiveness of labor just compensated for the diminishing productiveness of the land as it was called into use, the effect of increasing population would be to increase rent by lowering the margin of cultivation without reducing wages as a quantity, and to increase the average production. If we now suppose population still increasing, but, between the poorest quality of land in use and the next lower quality, to be a difference so great that the increased power of labor which comes with the increased population that brings it into cultivation cannot compensate for it—the minimum return to labor will be reduced, and with the rise of rents, wages will fall, not only as a proportion, but as a quantity. But unless the descent in the quality of land is far more precipitous than we can well imagine, or than, I think, ever exists, the average production will still be increased, for the increased effectiveness which comes by reason of the increased population that compels resort to the inferior quality of land attaches to all labor, and the gain on the superior qualities of land will more than compensate for the diminished production on the quality last brought in. The aggregate wealth production, as compared with the aggregate expenditure of labor, will be greater, though its distribution will be more unequal. Thus, increase of population, as it operates to extend production to lower natural levels, operates to increase rent and reduce wages as a proportion, and may or may not reduce wages as a quantity; while it seldom can, and probably never does, reduce the aggregate production of wealth as compared with the aggregate expenditure of labor, but on the contrary increases, and frequently largely increases it.