More on Knockers from Infoplease:

• knocker: meaning and definitions - knocker: Definition and Pronunciation
• Knockers - Knockers Goblins who dwell in mines, and point out rich veins of lead and silver. In Cardiganshire ...
• Oil the Knocker - Oil the Knocker (To). To fee the porter. The expression is from Racine, “On n'entre point ...
• Newgate Knocker - Newgate Knocker (A). A lock of hair twisted into a curl, usually worn by costermongers and other ...
• Black as a Newgate Knocker - Black as a Newgate Knocker A Newgate knocker is the fringe or lock of hair which costermongers and ...