Green’s Dictionary of Slang

Horn, the n.

[ety. unknown]

the Compter prison, in London.

[UK] ‘Well-Wishes to the Royal Family’ in Ebsworth Roxburghe Ballads (1885) V:1 151: Let the Lads and the Lasses set foot to foot in their turn; / And he that passes his Glasses may he never ’scape the Horn.