I need not add, as a restriction of this principle of discouraging the importation of foreign commodities (which become articles of a greater superfluous home-consumption) that when such a branch of trade becomes necessary to be carried on, in order to engage a neighbouring nation to consume of home-superfluities; in this case, the luxury of the consumers of the foreign produce, has an evident tendency to national improvement. If delicate wines, and raw silk, are imported as a return for salt herrings and raw hides, the support of such a trade is only the means of making the rich consume these articles of home-production, by converting them into burgundy and velvet. These considerations regard the augmentation, or at least the preservation of national wealth. If they are attended to, it is hardly possible that any part of what is already acquired, can go abroad; and in this case the whole balance of the exportation of natural produce becomes clear gain. There are still several things to be observed with regard to the exportation of natural produce. Such articles as are in great abundance, and are not produced in other countries, as wines in the southern countries of Europe, ought always to be exported by the inhabitants, because considerable profits must be made upon a trade where there is no rivalship; and on such occasions, a people ought to be wise enough to keep such profits for themselves. But if other nations will not receive them, unless they be imported by their own subjects, then the statesman may impose a duty upon exportation, which is one way of sharing the profits with the carriers. All the precaution necessary, in imposing this duty, is not to raise it so high as to diminish the demand; nor to give an encouragement to a neighbouring nation, to enter into competition for such a branch of trade. Neighbouring states which furnish the same articles of natural produce, regulate, commonly, the duties upon exportation, in such a manner as nearly to compensate all differences which strangers may find, between trading with the one or with the other. Or they grant particular privileges in point of trade, to the nations with whom they find it most for their advantage to trade. If the natural advantages upon such articles are less considerable, no duty can be imposed. Exportation may then be encouraged by granting still greater privileges to strangers or others, who may promote the exportation at little cost to the state.