Money. He grappled the cull's bit; he seized the man's money. A bit is also the smallest coin in Jamaica, equal to about sixpence sterling.

bit : Primarily a bite, a small piece, or by extension a small quantity; as, a bit of bread, a bit of fun. By error, the word is sometimes applied to liquids; as, “there is not a bit of water on the farm.” But when reference is to liquid to be drunk, it is more discriminating to say, not a bit, but a sip.

fourpence; in America a 12½ cent piece is called a bit , and a defaced 20 cent piece is termed a long bit. A bit  is the smallest coin in Jamaica, equal to 6d. Bit  usually means the smallest silver coin in circulation; also a piece of money of any kind. Charles Bannister, the witty singer and actor, one day meeting a Bow Street runner with a man in custody, asked what the prisoner had done; and being told that he had stolen a bridle, and had been detected in the act of selling it, said, “Ah, then, he wanted to touch the bit.”