Green’s Dictionary of Slang

1. one who demands money with menaces.

1882

A. Trumble Crooked Life in Nat. Police Gaz. (NY) 1 July 6/2: ‘Socco the Bracer’ fainted from loss of blood, and his companions, thinking he was dead, threw him overboard to lighten the boat.

2. a beggar who accosts passers-by with a hard-luck story in hope of alms.

1894		Mirror of Life 13 Jan. 12/3: Macers, braces, chippie chasers / What a lovely place Piccadilly is.
1907		N.Y. Times 27 Jan. Sun. Mag. 4: Three notorious ‘bracers’ of the ‘gentleman’ type were also plying their trade on the streets last week. Jean Dawson [...] was a man with a mournful eye and a heavy jaw, who posed as a stranded clerk or expert accountant, and reeked in the smell of liquor. His English was that of a gentleman, his request modest, his sufferings palpable as he shivered in thin clothes on a cold night, his pride seemed to be deeply wounded that he should be forced to beg.