To MILL a Ken,
to rob a House. Milling the Gig with a Betty, Breaking open the Door with an Iron Crow.
· 
· 
Entry taken from 1736 Canting Dictionary, by Nathan Bailey.
· ·
The Vulgar Tongue originally collected by Grose, 1811.
Also see examples in Canting Songs and Slang Rhymes collected by John S. Farmer (1896).