"But fileing of a Rumbo Ken,
My Boman is snabbled again."
-- A Canting Song, Harlequin Sheppard,
John Thurmond, 1728
Rumbo ken is a slang term of uncertain origin used in the 1700s in England to refer to a pawn shop.
It was also used to refer to Newgate prison, or prison in general, although it was more common to simply use 'the rumbo' in these cases.