No fixed capital can yield any revenue but by means of a circulating capital. The most useful machines and instruments of trade will produce nothing without the circulating capital which affords the materials they are employed upon, and the maintenance of the workmen who employ them. Land, however improved, will yield no revenue without a circulating capital, which maintains the labourers who cultivate and collect its produce.

To maintain and augment the stock which may be reserved for immediate consumption is the sole end and purpose both of the fixed and circulating capitals. It is this stock which feeds, clothes, and lodges the people. Their riches or poverty depends upon the abundant or sparing supplies which those two capitals can afford to the stock reserved for immediate consumption.

So great a part of the circulating capital being continually withdrawn from it, in order to be placed in the other two branches of the general stock of the society; it must in its turn require continual supplies, without which it would soon cease to exist. These supplies are principally drawn from three sources, the produce of land, of mines, and of fisheries. These afford continual supplies of provisions and materials, of which part is afterwards wrought up into finished work, and by which are replaced the provisions, materials, and finished work continually withdrawn from the circulating capital. From mines, too, is drawn what is necessary for maintaining and augmenting that part of it which consists in money. For though, in the ordinary course of business, this part is not, like the other three, necessarily withdrawn from it, in order to be placed in the other two branches of the general stock of the society, it must, however, like all other things, be wasted and worn out at last, and sometimes, too, be either lost or sent abroad, and must, therefore, require continual, though, no doubt, much smaller supplies.

Land, mines, and fisheries, require all both a fixed and a circulating capital to cultivate them; and their produce replaces with a profit, not only those capitals, but all the others in the society. Thus the farmer annually replaces to the manufacturer the provisions which he had consumed and the materials which be had wrought up the year before; and the manufacturer replaces to the farmer the finished work which he had wasted and worn out in the same 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.

In all countries where there is tolerable security, every man of common understanding will endeavour to employ whatever stock he can command in procuring either present enjoyment or future profit. If it is employed in procuring present enjoyment, it is a stock reserved for immediate consumption. If it is employed in procuring future profit, it must procure this profit either staying with him, or by going from him. In the one case it is fixed, in the other it is a circulating capital. A man must be perfectly crazy who, where there is tolerable security, does not employ all the stock which he commands, whether be his own or borrowed of other people, in some one or other of those three ways.

In those unfortunate countries, indeed, where men are continually afraid of the violence of their superiors, they frequently bury and conceal a great part of their stock, in order to have it always at hand to carry with them to some place of safety, in case of their being threatened with any of those disasters to which they consider themselves as at all times exposed. This is said to be a common practice in Turkey, in Indostan, and, I believe, in most other governments of Asia. It seems to have been a common practice