The Wealth of Nations by Part 2 Chapter 2 Page 127

a guinea to the person who issued it; a condition which the holders of such notes might frequently find it very difficult to fulfil, and which must have degraded this currency below the value of gold and silver money. An Act of Parliament accordingly declared all such clauses unlawful, and suppressed, in the same manner as in Scotland, all promissory notes, payable to the bearer, under twenty shillings value.

The paper currencies of North America consisted, not in bank notes payable to the bearer on demand, but in government paper, of which the payment was not exigible till several years after it was issued; and though the colony governments paid no interest to the holders of this paper, they declared it to be, and in fact rendered it, a legal tender of payment for the full value for which it was issued.