conceal this change. If it was commonly known, their great profit would tempt so many new rivals to employ their stocks in the same way, that, the effectual demand being fully supplied, the market price would soon be reduced to the natural price, and perhaps for some time even below it. If the market is at a great distance from the residence of those who supply it, they may sometimes be able to keep the secret for several years together, and may so long enjoy their extraordinary profits without any new rivals. Secrets of this kind, however, it must be acknowledged, can seldom be long kept; and the extraordinary profit can last very little longer than they are kept.
Secrets in manufactures are capable of being longer kept than secrets in trade. A dyer who has found the means of producing a particular color with materials which cost only half the price of those commonly made use of, may, with good management, enjoy the advantage of his discovery as long as he lives, and even leave it as a legacy to his posterity. His extraordinary gains arise from the high price which is paid for his private labor. They properly consist in the high wages of that labor. 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
