Clocks Glossary

Access Doors

Hinged doors or panel inserts on the sides of clocks which allow access to the movement. Access doors may contain glass panels which allow the movement to be viewed, or cloth panels (baffles) sometimes covered with decorative fretwork which permit strike and chime sounds to emanate from the case (see fret).


A noise or sound made by a clock at a specific time such as a bell, buzzer, chime or melody.

Anchor Escapement

An escapement developed in 1647 by William Clement which made possible the use of longer, more accurate pendulums.

Chime Rods

Solid tuned rods which produce a melody when struck by chime hammers. Chime rods are relatively inconspicuous. They are used instead of chime tubes and produce a more melodious sound.


A device which controls the motion of the movement gears. Through the escapement, the energy of the weights or springs is delivered to the pendulum or balance, permitting a tooth to escape from a pallet at exactly rate. Click the Escapement photo opposite to view.


The mechanical parts of a clock which are inserted into a case. The movement includes all of the parts responsible for keeping time. Including the time train (gears which operate the hands and activate the chime train) and the chime train (which operates the chimes).

Night Silencer

A feature of clocks with chimes and strike movements which turn off the chimes and strike in the evening (normally between the hours of 10PM and 7AM).


A rod suspended ‘from a fixed point which swings freely to and fro under the action of gravity. A clock pendulum determines the rate at which the movement measures time. See stick, lyre and mercury pendulum.

St. Michael Chimes

Chimes originally heard in the church of St. Michael in Charleston, the Bells were cast in London, were installed in the St. Michael Church steeple in Charleston, S.C. in 1764. During the Revolutionary War, the British took the bells back to England. After the war, a Charleston merchant bought them and sent them back to America.

Triple Chime

A clock movement which permits the chime melody to be changed by switching a chime selector lever. Most triple chime movements allow the user to select Westminster, Whittington or St. Michael Chimes (sometimes Winchester Chimes).


Solid weights or weight shells provide the motive force which drives the clock mechanism in tall case clocks. They are heavy metal cylinders suspended from chains or cables. Solid weights do not have end caps and cannot be taken apart. Shells have a cast iron or lead core encased in a brass shell which can be removed.

Westminster Chimes

Clock chimes on four bells or gongs, sounding like the tune played in the “Big Ben” Victoria clock tower in London. See the Chime section in this guide for more information.