Green’s Dictionary of Slang

cases n.

shoes.

1837		‘Sam Weller’s Adventures!’ in C. Hindley James Catnach (1878) 276: I renovate cases for feet.
1840		‘Monmouth Street’ in Lover’s Harmony No. 19 148: A slap-up coat for eighteen pence, / With dandy ‘cases’ and ‘tile’ so neat / They returned quite swells from Monmouth Street!
1896		‘Army Slang’ in Regiment 11 Apr. 31/1: [S]hirts are ‘grey-backs’ [...] and boots are ‘cases’’.