The remainder of what Mr. Ricardo has done for the philosophical exposition of the principles of foreign trade, is to shew, that the truth of the propositions now recapitulated is not affected by the introduction of money as a medium of exchange; the precious metals always tending to distribute themselves in such a manner throughout the commercial world, that every country shall import all that it would have imported, and export all that it would have exported, if exchanges had taken place, as in the example above supposed, by barter. To this branch of the subject we shall, in the sequel of this essay, return. At present it will be more convenient that we should continue to suppose, that exchanges take place by the direct trucking of one commodity against another. It is established, that the advantage which two countries derive from trading with each other, results from the more advantageous employment which thence arises, of the labour and capital--for shortness let us say the labour--of both jointly. The circumstances are such, that if each country confines itself to the production of one commodity, there is a greater total return to the labour of both together; and this increase of produce forms the whole of what the two countries taken together gain by the trade. It is the purpose of the present essay to inquire, in what proportion the increase of produce, arising from the saving of labour, is divided between the two countries. This question was not entered into by Mr. Ricardo, whose attention was engrossed by far more important questions, and who, having a science to create, had not time, or room, to occupy himself with much more than the leading principles. When he had done enough to enable any one who came after him, and who took the necessary pains, to do all the rest, he was satisfied. He very rarely followed out the principles of the science into the ramifications of their consequences. But we believe that to no one, who has thoroughly entered into the spirit of his discoveries, will even the minutiae of the science offer any difficulty but that which is constituted by the necessity of patience and circumspection in tracing principles to their results. Mr. Ricardo, while intending to go no further into the question of the advantage of foreign trade than to show what it consisted of, and under what circumstances it arose, unguardedly expressed himself as if each of the two countries making the exchange separately gained the whole of the difference between the comparative costs of the two commodities in one country and in the other. But, the whole gain of both countries together, consisting in the saving of labour; and the saving of labour being exactly equal to the difference between the costs, in the two countries, of the one commodity as compared with the other; the two countries taken together gain no more than this difference: and if either country gains the whole of it, the other country derives no advantage from the trade.