Green’s Dictionary of Slang

(UK Und.) the act – through plausible, beguiling speech – of luring victims into the hands of a team of confidence tricksters.

1741		Ordinary of Newgate Account of the Malefactors executed at Tyburn 18th Mar. 1740 part II 9: A new Member [...] who was esteemed a good Hand upon The Twang Adam Cove; that is, (could draw a man in by a fine Tongue, or Way of talking of those, whom they had a Design to impose upon).
1764		Bloody Register III 176: [as cit. 1741].