Those goods, which are part of the produce of the land and labour of Great Britain, having no market at home, and being deprived of that which they had abroad, must cease to be produced. The most round-about foreign trade of consumption, therefore may, upon some occasions, be as necessary for supporting the productive labour of the country, and the value of its annual produce, as the most direct.

When the capital stock of any country is increased to such a degree that it cannot be all employed in supplying the consumption and supporting the productive labour of that particular country, the surplus part of it naturally disgorges itself into the carrying trade, and is employed in performing the same offices to other countries. The carrying trade is the natural effect and symptom of great national wealth; but it does not seem to be the natural cause of it.