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“sextant”
A navigational instrument for determining latitude: A sextant can measure the angle between a heavenly body and the horizon.
The sextant was invented in 1730 by John Hadley (1682-1744) and can be used only in clear weather.
John Hadley was an English mathematician, inventor of the octant (reflecting quadrant) and precursor to the sextant around 1730.
This entry is located in the following unit:
Astronomy and related astronomical terms
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