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Ramsden Sextant

Ramsden Sextant image

Navigating in the sea: this sextant was one of the navigation tools invented in the 18th century by British mathematical instrument makers that permitted mariners to find their position much better than ever before. The sextant became the most essential instrument for celestial navigation, used to find the angle of a celestial body above the horizon. Jesse Ramsden, who made this sextant, also devised a machine to divide the scale on the sextant very precisely.