Green’s Dictionary of Slang

1. the member of a confidence tricking team who searches out and ensnares a suitable victim.

1600		J. Day Blind Beggar of Bednall-Green Act IV: There were a sort of Tumblers at Windham fair last week.
1608		Dekker Lanthorne and Candle-Light Ch. 4: He that hunts up and downe to find game, is called the Tumbler.
c.1698		B.E. Dict. Canting Crew n.p.: Tumbler [...] one that Decoys, or draws others into Play.
1725		New Canting Dict. [as cit. c.1698].
1737, 1759, 1760, 1776		Bailey Universal Etym. Eng. Dict. [as cit. c.1698].
1785, 1788, 1796		Grose Classical Dict. of the Vulgar Tongue n.p.: Tumbler [...] a sharper employed to draw in pigeons to game.
1811		Lex. Balatronicum [as cit. 1785].
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.
1848		Thackeray Vanity Fair III 263: The solemn, braggart ways of the poor tumblers.
1859		Matsell Vocabulum.
1866		Wild Boys of London I 110/1: You looks a great deal like Ikey Joe, the tumbler.

2. a prostitute.

1652

Laughing Mercury 25 Aug. - 8 Sept. 173: A new Committee of Tumblers convened together to think of some speedy way to satisfie some Souldiers that had latelty disturbed them , and beat up their quarters.