THE WKAETIl OP NATIONS.

163

boundary. Those, therefore, who have the command of morefood than they themselves can consume, are always willingto exchange the surplus, or, what is the same thing, the priceof it, for the gratifications of this other kind. What is overand above satisfying the limited desire, is given for theamusement of those desires which cannot be satisfied, butseem to be altogether endless. The poor, in order to obtainfood, exert themselves to gratify those fancies of the rich, andto obtain it more certainly, they vie with one another in thecheapness and perfection of their work. The number ofworkmen increases with the increasing quantity of food, orwith the growing improvement and cultivation of the lands;and as the nature of their business admits of the utmost sub-divisions of labour, the quantity of materials which they canwork up increases in a much greater proportion than theirhumbers. Hence arises a demand for every sort of materialwhich human invention can employ, either usefully or brna-mentally, inbuilding, dress, equipage, or household furniture;for the fossils and minerals contained in the bowels of theearth, the precious metals, and the precious stones.

Food is in this manner, not only the original source of rent,but every other part of the produce of land which afterwardaffords rent, derives that part of its value from the improve-ment of the powers of labour in producing food by means ofthe improvement and cultivation of land.

Those other parts of the produce of land, however, whichafterward afford rent, do not afford it always. Even in im-proved and cultivated countries the demand for them is not al-ways such as t.o afford a greater price than what is sufficientto pay the labour, and replace, together with its ordinary pro-fits, the stock which must be employed in bringing them tomarket. Whether it is or is not such, depends upon differentcircumstances.

Whether a coal-mine, for example, can afford any rent,depends partly upon its fertility, and partly upon its situation.

A mine of any kind may be said to be either fertile or bar-ren, according as the quantity of mineral which can bebrought from it by a certain quantity of labour, is greater orless than what can be brought by an equal quantity from thegreater part of other mines of the same kind.

Some coal-mines, advantageously situated, cannot bewrought on account of their barrenness. The produce doesnot pay the expense. They can all’ord neither profit nor rent.