solutions to the problem of things that formerly appeared to have no name

...money rented ad pompam. In such a contract, ... money was transferred to a bailee for the specific purpose of display so that he might impress others with his wealth. The money was not consumed, but used, and the charge was for its use. The Gloss's treatment here seems to assume that the fundamental distinction between this contract and a loan is the incidence of risk.

Noonan, The Scholastic Analysis of Usury