If, for example, potatoes should become the general and common food of the people, as rice is in some countries, one fourth, or one half of the land now in cultivation, would probably be immediately abandoned; for if, as Adam Smith says, an acre of potatoes will produce six thousand weight of solid nourishment, three times the quantity produced by the acre of wheat, there could not be for a considerable time such a multiplication of people, as to consume the quantity that might be raised on the land before employed for the cultivation of wheat; much land would consequently be abandoned, and rent would fall; and it would not be till the population had been doubled or trebled, that the same quantity of land could be in cultivation, and the rent paid for it as high as before.