COACH-WHEEL,
as, A Fore-Coach-Wheel Half a Crown. A Hind-Coach-Wheel, a Crown or Five-shilling Piece.
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Entry taken from 1736 Canting Dictionary, by Nathan Bailey.
Coach Wheel in the 1811 Vulgar Tongue
Also see examples in Canting Songs and Slang Rhymes collected by John S. Farmer (1896).