price which is paid for his private labour. They properly consist in the high wages of that labour. But as they are repeated upon every part of his stock, and as their whole amount bears, upon that account, a regular proportion to it, they are commonly considered as extraordinary profits of stock.

Such enhancements of the market price are evidently the effects of particular accidents, of which, however, the operation may sometimes last for many years together.

Some natural productions require such a singularity of soil and situation that all the land in a great country, which is fit for producing them, may not be sufficient to supply the effectual demand. The whole quantity brought to market, therefore, may be disposed of to those who are willing to give more than what is sufficient to