Green’s Dictionary of Slang

1. one who specializes in swindling lottery office-keepers.

1781		G. Parker View of Society II 64: Carrier Pigeons. This is one of the most curious species of villainy [...] I mean Lottery-Office Keepers. This is practiced by three men and a woman.
1785		Grose Classical Dict. of the Vulgar Tongue n.p.: Carrier pigeons, sharpers who attend the drawing of the lottery in Guildhall, and as soon as a number or two are drawn, write them on a card and run with them to a confederate, who is waiting near at hand, and ready mounted; with these numbers he rides full speed to some distant insurance office before fixed on, where there is another of the gang, commonly a decent looking woman, who takes care to be at the office before the hour of drawing, to her he secretly gives the number, which she insures for a considerable sum, thus biting the biter.
1859, 1860		Hotten Dict. of Modern Sl. etc.
1864, 1867, 1870		Hotten Sl. Dict.
1873		Sl. Dict.
1901		Argus (Melbourne) 20 Sept. 6/4: Amongst these small fry of the profession [are] the carrier pigeon, a swindler’s agent, the cat and kitten stealer, whose special line is quart and pint pots, the Charley pilcher [sic], a very poor kind of cheat, the dido, who steals from carts.

2. one who places bets on commission.

1873		Sl. Dict.
1895		Crowe Aus. Sl. Dict. 15: Carrier Pigeon, [...] one among betting men who runs from place to place with commissions.