But here it is objected, that although the proportion between gold and silver, in the English coin, were set upon a par with that of the metals in the London market, still one species may be exported with profit, providing the proportion be different in other nations. There is little force in this objection, and were there any, it would be an additional argument for the imposition of coinage; because by this the exportation of either of the species, for the sake of any small difference which may sometimes be found between the proportion of the metals in the different markets of Europe, would be prevented. This circumstance however requires a more particular examination. It is a principle in commerce, that the demand for any commodity raises the value of it; and every nation knows how to profit of a demand for what they have. [Sidenote: How the proportion of the metals is kept nearly the same in all European markets.] Whenever, therefore, one of the metals bears an under value in one nation, below what it bears in another, that under value makes that species more demanded by strangers, and it consequently rises in its value, even at home. [Sidenote: Because when home demand disturbs the proportion, foreign trade brings it even again.] By this principle the proportion between the metals in European markets is kept nearly the same, and the small difference which is found does not so much proceed from the demand of foreign trade, as from the taste of the inhabitants. The foreign demand tends to set the proportion even in all markets, and the internal demand for one metal preferably to another, is what makes it vary. The carrying the metals backwards and forwards is attended with risque and expence; there is not, therefore, so much danger of a nation’s being stripped of one of its species of current coin by such a trade, as there is when the proportion of the market price of the metals is different, at home, from that observed in the coin; because in the last case, every one may profit of the disproportion, at the trifling expence of melting down the rising species. [Sidenote: Coin of gold and silver should be proportioned to the rate of the market at home,] From this we may conclude, that nations ought to regulate the proportion of the metals in their coin, according to the market price of them at home, without regard to what it is found to be in other nations; because they may be assured, that the moment any difference in the market price shall begin to be profited of, that very demand will alter the proportion, and raise the market price of the metal sought for by foreigners. While the coin, therefore, is kept at the proportion of the market at home, and while the denominations of both species are made to keep pace with it, it will be utterly impossible for any nation to hurt another by any such traffic in the metals.