Ballotiere knob :

Solid loop on a dual control cremone bolt, controlled by lock.

Bearing plate :

Metal plate, carved and often chiselled or mounted, which forms the front face of the lock.

Bit :

Part of the key attached to the end of the shaft and which works the moving parts of the lock. Its teeth or serrations allow it to pass through the lock trims or fittings.

Bolt :

Moving part of the lock that inserts into the strike plate. The catch bolt is moved using the knob; the lock bolt by the key.

Case :

Protects the mechanism of an apparent lock, made from cast iron, chiselled or gold-plated, or in cast copper (18th Century). Sometimes called box staple or body of the lock.

Case (- lock) :

Apparent lock comprising an iron case, covered with a sheet of chiselled decorated copper.

Cremone bolt :

Sliding rod, which enters the upper and lower strike plates of a window or door.