Maskelyne, Nevil 1732-1811
English astronomer

Born in London, after being educated at Westminster School he went on to study divinity at Trinity College, Cambridge. He joined the Royal Greenwich Observatory in 1755. In 1763 he produced the British Mariner's Guide and went to Barbados to test chronometers. In 1765 he was appointed Astronomer Royal. He improved methods and instruments of observation, invented the prismatic micrometer and made important observations. He went to St Helena to observe the transit of Venus, the aim being to make better estimates of the Earth-Sun distance. In 1767 he founded the Nautical Almanac. He also measured the Earth's density from the deflection of the plumb-line at Schiehallion in Perthshire (1774), obtaining a value between 4.56 and 4.87 times that of water. An ordained minister, he was rector from 1775 of Shrawardine, Salop, and from 1782 of North Runcton, Norfolk.