The Wealth of Nations by Part 4 Chapter 7 Page 141

of his correspondent, he cannot make up that of Great Britain. In a trade of which the returns are very distant, the profit of the merchant may be as great or greater than in one in which they are very frequent and near; but the advantage of the country in which he resides, the quantity of productive labour constantly maintained there, the annual produce of the land and labour must always be much less.

That the returns of the trade to America, and still more those of that to the West Indies are, in general, not only more distant but more irregular, and more uncertain too, than those of the trade to any part of Europe, or even of the countries which lie round the Mediterranean Sea, will readily be allowed, I imagine, by everybody who has any experience of those different branches of trade.