Green’s Dictionary of Slang

block n.5

1. (Aus./US Und.) a watch; thus block-dealer, a watch seller, a jeweler [block and tackle n.1 ].

[Aus]Register (Adelaide) 4 Jan. 10/3: I’ll take a ‘leather’, but I won’t touch ‘reds‘ or a ‘block’.
[US]Jackson & Hellyer Vocab. Criminal Sl. 17: block [...] A watch. Example: ‘The wire rung six blocks in the breaks,’ i. e., ‘The tool (pickpocket) detached six watches from their rings in the crowded exit.’.
[US]G. Henderson Keys to Crookdom 397: Block. Solid-gold watch.
[US] ‘Und. and Its Vernacular’ in Clues mag. 158–62: block-dealer Watch-dealer; jeweler.
[US]Irwin Amer. Tramp and Und. Sl.
[US]‘Goat’ Laven Rough Stuff 39: He told us of different houses throughout the country that dealt in brass peddling, such as blocks, which is what watches are called in the West. In the East they call ’em soupers, and in England, kettles.
[US]Ersine Und. and Prison Sl. 19: block, n. 1. a cheap watch.
[UK] (ref. to 1920s) L. Duncan Over the Wall 112: Then the junk – small rocks, hoops and blocks – ticking rhythmically.
[US]Goldin et al. DAUL 29/2: Block. A genuine gold-cased watch as differentiated from thin-plated watches.
[US]Ragen & Finston World’s Toughest Prison 791: block – A watch.
[Aus] ‘Whisper All Aussie Dict.’ in Kings Cross Whisper (Sydney) xxxii 6/1: block: A dud watch. They looked like gold but would turn the wrist green after a very short while.
[Aus]Bulletin (Sydney) 26 Apr. 44: ‘What was you duddin’? The Ampol buildin’ or somethin ?’ ‘Blocks. Just bottom shelf stuff with face lifts for the mugs.’.
[Aus]R. Aven-Bray Ridgey-Didge Oz Jack Lang 21: Block Dud watch.

2. (Can. prison) a cigarette lighter [resemblance].

[Can]R. Caron Go-Boy! 23: OK, boys, Mother Goose sent me over to collect your blocks for refuelling.

In compounds

block and tackle (n.)

see separate entry.