Green’s Dictionary of Slang

1. money extorted from a new prisoner, either as a gaoler’s fee or as drink-money for the other prisoners [the practice was abolished in 1824, after which time the term was restricted to SE].

1592		Greene Quip for an Upstart Courtier E2: Let a poore man but be arrested into one of the counters [...] hee shall be almost at an angels charge, what with garnish, crossing and wiping out of the boke, turning the key.
c.1617		G. Mynshall Essayes and Characters of a Prison n.p.: [fees of the Kings Bench prison] For turning the Key 14s. 4d. For Garnish 2s. 6d. For Chamberlain and Nurse 4s. 0d.
1630		J. Taylor ‘A Brood of Cormorants’ in Works (1869) III 10: Then the old prisoners garnish doe demand, / Which straight must be discharged out of hand.
1662		Fuller Worthies II (1840) 447: The air of Marshland [...] is none of the wholesomest [...] strangers coming hither are clapt on the back in an ague. [...] When such prisoners have paid the bailiff’s fee and garnish, and with time [...] they become habituated to the air.
1676		A Newgate ex-prisoner A Warning for House-Keepers 6: And when we come unto to the Whitt / For garnish they do cry.
1680		‘The Poet’s Dream’ in Ebsworth Roxburghe Ballads (1893) VII:1 13: The Jayl-fees many are bound to rue, /The garnish, bed, and Turn-key too, / Expects an unexpected due.
1699		N. Ward London Spy IV 83: The ill-looking Vermin [...] came hovering round us, like so many Canibals, with such devouring Countenances, as if a Man had been but a Morsel with ’em, all crying out Garnish, Garnish.
1708		J. Hall Memoirs (1714) 15: They turn him out to the Convicts, who hover about him [...] for Garnish, which is Six Shillings and Eight Pence.
1719		A. Smith Lives of Most Notorious Highway-men, etc. (1926) 206: Garnish, money that is customarily spent by a prisoner at his imprisonment.
1725		New Canting Dict. n.p.: Garnish-money what is customarily spent among the Prisoners at first coming in.
1731		Prisoners Opera 5: But, dear Sir, as you’re a stranger, / Down your Garnish you must lay.
1737, 1759, 1760, 1776		Bailey Universal Etym. Eng. Dict. [as cit. 1725].
1751		Fielding Amelia (1926) I 14: Mr. Booth [...] was no sooner arrived in the prison, than a number of persons gathered round him, all demanding garnish.
1781–2		J. Messink Choice of Harlequin I viii: Your jazy pays the garnish, unless the fees you tip.
1790		Banquet of Wit 20: [When] Beelzebub’s bum-bailiffs lay hold of you [...] you think I will pay your garnish: but I won’t.
c.1800		‘The Blue Lion’ in Holloway & Black I (1975) 32: Without delay must garnish pay.
1812		Vaux Vocab. of the Flash Lang.
1822		(con. early 17C) W. Scott Fortunes of Nigel II 125: The payment of garnish conforming to their circumstances, is never dispensed with.
1835		G. Kent Modern Flash Dict.
1846		Swell’s Night Guide 120/1: Garnish, money demanded of people entering prison.
1859		G.A. Sala Twice Round the Clock 23: The inhuman Mr. Lockit [...] threatened to clap on extra fetters in default of an immediate supply on the captain’s part of ‘garnish’ or jail fees.
1864, 1867, 1870		Hotten Sl. Dict.
1873		Sl. Dict. 173: Garnish the douceur or fee which, before the time of Howard the philanthropist, was exacted by the keepers of gaols from their unfortunate prisoners for extra comforts. The practice of garnishing is by no means as defunct as some folk seem to think.
1884		A. Griffiths Chronicles of Newgate 5: Unwritten but accepted customs suffered the general body to exact ‘garnish’ or ‘chummage’ from newcomers.
1898		W. Besant Orange Girl II 12: They all crowded round, crying ‘Garnish! garnish!’ I held up my hands: I assured them that I was penniless.

2. fetters [although both Johnson, Dictionary (1755) and F&H both cite this meaning, it may have stemmed from a mis-reading of sense 1].

1755		Johnson Dict. Eng. Lang. (1785) n.p.: Garnish. [In gaols] Fetters. A cant term.
1890–1904		Farmer & Henley Sl. and Its Analogues.
1949		Monteleone Criminal Sl. (rev. edn) 95: garnish Handcuffs.

3. (UK Und.) a bribe.

1908

D. Stewart Wild Tribes of London in Illus. Police News 22 Feb. 12/4: ‘De damt police always think I got nothing to do [...] but to drop ’em garnish’.