Glossary
Ten terms that carry most of the trade. Each one is shorter than the argument it settles.
- Escapement
- The mechanism that releases the train in even steps, turning stored wind into steady time.
- Fusee
- A spiral pulley that evens out the pull of the mainspring as it unwinds.
- Great wheel
- The first and largest wheel of the going train, driven by the barrel.
- Lunarium
- A mechanism showing the Moon's phase and position against the stars.
- Orrery
- A mechanical model of the solar system, named for the Earls of Orrery.
- Precession
- The slow cone traced by the Earth's axis over some 26,000 years.
- Ring set
- The concentric engraved bands that carry the planets of a model.
- Tellurion
- A model of the Earth-Moon system and its seasons.
- Train
- The geared chain that carries motion from barrel to dial.
- Winding square
- The squared socket that receives the winding key.