The Wealth of Nations by Part 4 Chapter 3 Page 17

Thirdly, and lastly, in some places, as at Amsterdam, Hamburg, Venice, etc., foreign bills of exchange are paid in what they call bank money; while in others, as at London, Lisbon, Antwerp, Leghorn, etc., they are paid in the common currency of the country. What is called bank money is always of more value than the same nominal sum of common currency.

A thousand guilders in the Bank of Amsterdam, for example, are of more value than a thousand guilders of Amsterdam currency. The difference between them is called the agio of the bank, which, at Amsterdam, is generally about five per cent. Supposing the current money of the two countries equally near to the standard of their respective mints, and that the one pays foreign bills in this common currency, while the other pays them in bank money, it is evident that the computed