Ramsden, Jesse, an English mathematical instrument-maker; born in Salterhebble, near Halifax, Yorkshire, England in 1735. About 1755 he moved to London, where his skill as an engraver, recommended him to the mathematical instrument-makers. He so improved the sextant that its range of error was diminished from 5 minutes to 30 seconds. He died in Brighton, England, Nov. 5, 1800.
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