TOWER,
a Cant Word, used to denote bad, or clipped Money: as, They have been round the Tower with it; te he Piece of Money has been clipt.
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Entry taken from 1736 Canting Dictionary, by Nathan Bailey.
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Tower in the 1811 Vulgar Tongue
Also see examples in Canting Songs and Slang Rhymes collected by John S. Farmer (1896).