The Wealth of Nations by Part 4 Chapter 6 Page 7

But it does not become bound to admit them upon any better terms than those of any other nation, of France or Holland for example.

The crown of Great Britain, on the contrary, becomes bound to admit the wines of Portugal upon paying only two-thirds of the duty which is paid for those of France, the wines most likely to come into competition with them. So far this treaty, therefore, is evidently advantageous to Portugal, and disadvantageous to Great Britain.

It has been celebrated, however, as a masterpiece of the commercial policy of England. Portugal receives annually from the Brazils a greater quantity of gold than can be employed in its domestic commerce, whether in the shape of coin or of plate. The surplus is too valuable to be allowed to lie idle and locked up in coffers, and as it