Green’s Dictionary of Slang

see cant of dobbin n.

(US Und.) the robbing of a shop as soon as it opens, by one person distracting the store porter and the other making the robbery.

1859

Matsell Vocabulum 26: dobing lay To steal from stores early in the morning. Two thieves enter a store, as soon as the porter opens it; one of them inquires about some goods he pretends he was looking at the day before, and wishes to see them. The goods inquired for are either in the back of the store or upstairs. In the absence of the porter, the other fellow robs the store.

(UK Und.) the stealing of ribbons from haberdashers, usu. performed by women.

1781		G. Parker View of Society II 149: Going upon the Dobin, is done by a woman about seven o’clock on a winter’s morning, who is dressed like a servant-maid, with a cream-pot in one band, and Betty in the other; and a number of young Dubs hanging by her side; no hat or cloak on as she passes through a street. If she spies an apprentice at a Haberdasher’s opening the shop windows, she applies for a yard and a half of ribbon, but takes care to stand in the darkest part of the shop [...] As soon as the ribbon-drawer is set before her in order to choose the colour, she begins to work [...] It has been well known, that in a few mornings a woman has made on the Dobbin Rig two or three hundred yards of ribbon.
c.1786		Grose Classical Dict. of the Vulgar Tongue ms. additions n.p.: Dobin Rig. Stealing Ribbons from Haberdashers early in the Morning or late at Night. Generally practised by Women in the disguise of Maid Servants.
1789		G. Parker Life’s Painter 137: It’s not the first time I have fenced a rum-screen with him, and Moll when she used to go upon the Dobbin, she has told him many a cant.
1796		Grose Classical Dict. of the Vulgar Tongue (3rd edn).
1811		Lex. Balatronicum.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.