A quadrant is a simple tool used to measure vertical angles of separation (altitude above the horizon). The history of the classical quadrant is lost in antiquity.These angles, combined with the properties of triangles, has allowed mankind to measure his world and thereby advance civilization throughout history.
Each year, after the annual floods, Egyptian engineers re-established farmers' boundaries using a horizontal version of the quadrant (triangulating).
During the Dark Ages, the Arabs nurtured the science of astronomy and developed the primitive quadrant into a more advanced tool, called an ASTROLABE. The first brave mariners that dared to leave sight of land in their sailing ships did so with the help of these instruments, making it possible for them to determine their position on the Earth to within a few degrees of accuracy; close enough to find land again!
(For information on how Columbus used the quadrant - How Columbus used a Quadrant)
(last updated 8/31/98)