Previous


Harris Sextant

Harris Sextant

Harris Sextant

Sextants are optical instruments that measure the angular distance between any two points, such as a star and the horizon. A sextant's frame supports a graduated arc, a movable index arm that represents the radius of the circle, two mirrors and a small telescope. The mirror sextant was developed in the mid-1700s, based on the work of John Hadley in England and Thomas Godfrey in America. Sextants were the primary navigation tools used by mariners and pilots until the mid-1900s.