Halley, Edmond -
(1656-1742): English astronomer and geophysicist but also diplomat and commander in the Royal Navy. He catalogued the stars of the southern skies and mapped magnetic variation, winds, tides, and related elevation to atmospheric pressure. Other topics he studied included evaporation and salinity of lakes, optics of the rainbow, mortality tables, size of the atom, acceleration of the moon, proper motion of stars, astronomy of comets. He predicted the return of a major comet ("Halley's Comet") for the year 1758.