Thus then it appears, that the improvement of a manufacture in any country tends to alter the distribution of the precious metals amongst the nations of the world: it tends to increase the quantity of commodities, at the same time that it raises general prices in the country where the improvement takes place.
To simplify the question, I have been supposing the trade between two countries to be confined to two commodities, to wine and cloth, but it is well known that many and various articles enter into the list of exports and imports. By the abstraction of money from one country, and the accumulation of it in another, all commodities are affected in price, and consequently encouragement is given to the exportation of many more commodities besides money, which will therefore prevent so great an effect from taking place on the value of money in the two countries, as might otherwise be expected.
Beside the improvements in arts and machinery, there are various other causes which are constantly operating on the natural course of trade, and which interfere with the equilibrium, and the relative value of money. Bounties on exportation or importation, new taxes on commodities, sometimes by their direct, and at other times by their indirect operation, disturb the natural trade of barter, and produce a consequent necessity of importing or exporting money, in order that prices may be accommodated to the natural course of commerce; and this effect is produced not only in the country where the disturbing cause takes place, but, in a greater or less degree, in every country of the commercial world.
This will in some measure account for the different value of money in different countries; it will explain to us why the prices of home commodities, and those of great bulk, are, independently of other causes,