wry mouth and a pissen pair of breeches, n. — Green’s Dictionary of Slang

wry mouth and a pissen pair of breeches n.

[SE wry, contorted, twisted + pissen, pissed upon; i.e. the effect on the victim’s bodily functions]

a hanging.

1607		Dekker Iests to make you merie 27: [T]is but halfe an howres hanging, twill saue mee halfe a yéares drinking [...] the knot vnder the eare, and a wry mouth will doe it.
1785, 1788, 1796		Grose Classical Dict. of the Vulgar Tongue.
1811		Lex. Balatronicum.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.