time. This is the real exchange that is annually made between those two orders of people, though it seldom happens that the rude produce of the one and the manufactured produce of the other, are directly bartered for one another; because it seldom happens that the farmer sells his corn and his cattle, his flax and his wool, to the very same person of whom he chooses to purchase the clothes, furniture, and instruments of trade which he wants. He sells, therefore, his rude produce for money, with which he can purchase, wherever it is to be had, the manufactured produce he has occasion for. Land even replaces, in part at least, the capitals with which fisheries and mines are cultivated. It is the produce of land which draws the fish from the waters; and it is the produce of the surface of the earth which extracts the minerals from its bowels.
The produce of land, mines, and fisheries, when their natural fertility is equal, is in proportion to the extent and proper application of the capitals employed about them. When the capitals are equal and equally well applied, it is in proportion to their natural fertility.