Green’s Dictionary of Slang

(UK Und.) a rich fool, as such a potential target for robbery; thus kimblocky adj., having more money than sense.

c.1850

Duncombe New and Improved Flash Dict. n.p.: Kimblocks fools, boasting of and shewing the money they may have about them: or paying for a glass of liquor take a whole handfull of silver and gold out together. Kimblocky more money than wit.