CHAPTER II.

The improvements which increase the productive powers of the land, are such as the more skilful rotation of crops, or the better choice of manure. These improvements absolutely enable us to obtain the same produce from a smaller quantity of land. If, by the introduction of a course of turnips, I can feed my sheep besides raising my corn, the land on which the sheep were fed becomes unnecessary, and the same quantity of raw produce is raised by the employment of a less quantity of land. If I discover a manure which will enable me to make a piece of land produce 20 per cent. more corn, I may withdraw at least a portion of my capital from the most unproductive part of my farm. But, as I have before observed, it is not necessary that land should be thrown out of cultivation, in order to reduce rent: to produce this effect, it is sufficient that successive portions of capital are employed on the same land with different results, and that the portion which gives the least result should be withdrawn. If, by the introduction of the turnip husbandry, or by the use of a more invigorating manure, I can obtain the same produce with less capital, and without disturbing the difference between the productive powers of the successive portions of capital, I shall lower rent; for a different and more productive portion will be that which will form the standard from which every other will be reckoned. If, for example, the successive portions of capital yielded 100, 90, 80, 70; whilst I employed these four portions, my rent would be 60, or the difference between