Glossary

of watchmaking

A

  • A/H

    Half-oscillations (also known as “beats” or “vibrations”) per hour. Two half-oscillations produce the familiar “tick-tock” of a mechanical watch. Together, two beats comprise one oscillation.

  • Display of the time by means of a pair of hands. The relative positions of the hour-hand and minute-hand combine to indicate the current time.

  • Two-armed connective lever between the gear-train and balance. The anchor conveys energy to the balance.

  • A watch whose mainspring is wound by the motions of the wearer’s arm. These motions cause an oscillating weight (rotor) to turn. The rotation of the rotor tightens the mainspring. Invented by Abraham L. Perrelet (circa 1770).