Monkey’s Money

I will pay you in monkey’s money (“en monnaie de singe”)—in goods, in personal work, in mumbling and grimace. The French had a law that when a monkey passed the Petit Pont, of Paris, if it was for sale it was to pay four deniers (two-thirds of a penny) for toll; but if it belonged to a showman and was not for sale, it should suffice if the monkey went through his tricks.