When was the First Sextant Used?

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Sextant is an instrument that navigators use to find their position. It was invented by John Hadley of Britain and Thomas Godfrey of the United States in 1731. It made navigation easier, and sea travel much safer. The sextant measures how high the Sun or star, such as the Pole Star, is above the horizon. The navigator looks through lenses and mirrors fixed to the sextant and views the Sun or Star and the horizon. A scale on sextant gives the height of the Sun or star. From this and the time of observation, the navigator can work out the position.

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