The lower adjustable bearing for the endless screw in the governor. The potence holds the lower pivot of the endless screw and, by means of the regulating screw, allows the proper depthing of the endless screw to the second wheel.

A unit of length approximately 1.066 inches used to measure the length of cylinders on a music box.

In a pneumatic action, a flexible diaphragm (made of thin leather or other material) which, when one face is acted upon by air pressure or suction, causes a valve or key to operate. * Synonym: puff (mainly European usage).

In a disc music box, the bar which by means of hold-down wheels holds the disc against the star wheels when in the playing position. See hold-down arm.

Short diapason-like pipe in band organs and pipe organs, sometimes mounted on the front of the facade. Plays with a bright string-like tone.