The Wealth of Nations by Part 4 Chapter 3 Page 18

exchange may be in favour of that which pays in bank money, though the real exchange should be in favour of that which pays in current money; for the same reason that the computed exchange may be in favour of that which pays in better money, or in money nearer to its own standard, though the real exchange should be in favour of that which pays in worse.

The computed exchange, before the late reformation of the gold coin, was generally against London with Amsterdam, Hamburg, Venice, and, I believe, with all other places which pay in what is called bank money. It will by no means follow, however, that the real exchange was against it. Since the reformation of the gold coin, it has been in favour of London even with those places. The computed exchange has generally been in favour of London with Lisbon, Antwerp, Leghorn, and,