Quadrant
device · 150 · Ancient world
An angle gauge for measuring the altitude of celestial bodies.
What it is made of
- Quarter circle with degree scale — has part. A scale from 0 to 90°.
- Sighting vanes — has part. A sight for the celestial body.
- Plumb bob — has part. A plumb line shows the vertical.
Principles and materials it uses
- Bronze — is made of. Quadrants are bronze or wooden.
- Universal gravitation — uses. The angle is read against a plumb line.
History: what it evolved from and what it influenced
- Astrolabe — evolved from. A simplified angle gauge.
Things built in a similar way
- Jacob’s staff — works like. Two angle gauges for measuring the altitude of celestial bodies.