In order to remedy the inconvenience to which this disadvantageous exchange must have subjected their merchants, such small states, when they began to attend to the interest of trade, have frequently enacted that foreign bills of exchange of a certain value should be paid, not in common currency, but by an order upon, or by a transfer in the books of a certain bank, established upon the credit, and under the protection of the state, this bank being always obliged to pay, in good and true money, exactly according to the standard of the state. The banks of Venice, Genoa, Amsterdam, Hamburg, and Nuremberg, seem to have been all originally established with this view, though some of them may have afterwards been made subservient to other purposes. The money of such banks, being better than the common currency of the country, necessarily bore an agio, which was greater or smaller, according as the currency was supposed to be more or less degraded below the standard of the state. The agio of the bank of Hamburg, for example, which is said to be commonly about fourteen per cent. is the supposed difference between the good standard money of the state, and the clipt, worn, and diminished currency, poured into it from all the neighbouring states.