Green’s Dictionary of Slang

bulk n.1

also bulker
[? SE bulk, a large lump; thus the image of this human ‘lump’ pushing one around; OED also offers obs. 14C bulk, ‘? to beat’]

1. (UK Und.) a thief’s, esp. a pickpocket’s, accomplice who jostles the victim while their pocket is picked.

[UK]Wandring-Whores Complaint title: A full discovery of the whole Trade of [...] Bawds, Whores, Fyles, Culls, Mobs, Budges, Shop-lifts, Glasiers, Mills, Bulkers, [...] and all other Artists, who are, and have been, Students of Whittington Colledge.
Wandring Whores Complaint 4: The eighth was a Bulk, that can bulk any Hick .
[UK]Nicker Nicked in Harleian Misc. II (1809) 108: There come in shoals of hectors, trepanners, [...] shop-lifters, foilers, bulkers, droppers.
[UK]‘L.B.’ New Academy of Complements 204: The eighth is a Bulk, that can bulk any Hick.
[Ire]Head Canting Academy (2nd edn) 75: Their Markets are fairs, crowds, Churches and places where great store of people resort, the Bulker jostles them up, and the File doth the work.
[UK]C. Hitchin Regulator 20: A Bulk or Gammon, alias that is he that jostles up to a Man, whilst another picks his Pocket.
[UK]New Canting Dict. n.p.: bulk an Assistant to a File or Pickpocket, who jostles a Person up against the Wall, while the other picks his Pocket.
[UK]J. Dalton Narrative of Street-Robberies 60: A Bulk, One who stops the Woman, whilst another picks her Pocket.
[UK]Proceedings at Sessions (City of London) Sept. 11/2: He saw some People standing at the Door, and there was the Prisoner and a Bulk-woman [...] and the Bulk-woman gave the Prosecutor a Push, or hit him on the Shoulder.
[UK]Scoundrel’s Dict. 29: The Bulk, or one that is his Assistant, in creating Quarrels by jostling, &c. to gather a crowd that the Diver may have a better Opportunity to effect his Purpose.
[UK] ‘Come All You Buffers Gay’ in Farmer Musa Pedestris (1896) 53: Let your pal that follows behind, / Tip your bulk pretty soon.
[UK](con. 1710–25) Tyburn Chronicle II in Groom (1999) xxviii: A Bulk or Gammon He that jostles a Man, while another picks his Pocket.
[UK]Grose Classical Dict. of the Vulgar Tongue n.p.: The file or bungnipper, goes generally in company with two assistants, the adam tiler and another called the bulk or bulker, whose business is to jostle the person they intend to rob and push him against the wall while the file picks his pocket, and gives the booty to the adam tiler who scours off with it; (cant).
[UK]G. Andrewes Dict. Sl. and Cant.
[UK]Lex. Balatronicum [as cit. 1785].
[UK]Flash Dict.
[UK]G. Kent Modern Flash Dict.
[UK] ‘Charley The Buzzman & Mot!’ Flash Casket 67: Where are you paddling on tip toe light, / An old Bulk ax’d, a mot one night; / Nosing for gulpins, who want a bed, / Charley said she I am hither led.
[UK]Flash Dict. in Sinks of London Laid Open.
[UK]Duncombe New and Improved Flash Dict.
[UK] ‘Thief-Catcher’s Prophecy’ in W.H. Logan Pedlar’s Pack of Ballads 143: [as cit. 1671].

2. see bulker n.1 (1)

In compounds

bulk and file (n.) [file n.1 (1)]

(UK Und.) a pickpocket and their assistant (albeit in reverse order); one jostles the victim, the other picks the pocket.

[Ire]Head Eng. Rogue I 48: Bulk and File, The Pick-pocket and his mate.
[Ire]Head Canting Academy (2nd edn).
[UK]B.E. Dict. Canting Crew.
[UK]A. Smith Lives of Most Notorious Highway-men, etc. (1926) 203: Bulk and File, one jostles while the other picks the pocket.
[UK]Grose Classical Dict. of the Vulgar Tongue n.p.: bulk and file two pickpockets; the bulk jostles the party to be robbed, and the file does the business.
[UK]Lex. Balatronicum.
[UK]Egan Grose’s Classical Dict. of the Vulgar Tongue.
[US]Matsell Vocabulum.
[US]Trumble Sl. Dict. (1890).
[Aus]Crowe Aus. Sl. Dict. 13: Bulk and File, shoplifters; pickpockets who rob a victim by jostling him from one to the other.
[Aus]Argus (Melbourne) 20 Sept. 6/4: The pickpocket [...] does the bulk and file when two working in collusion jostle a victim in a crowd.
bulk-monger (n.) [sfx -monger]

a prostitute who consorts with thieves, esp. pickpockets.

[UK]John F---g Epistle of a Reformed Rake 9: Street-walkers and Bulk-mongers sometimes take a Youth’s own Handkerchief, instead of Three-half-pence, (half-wet-half-dry) for a Manual-abortion.