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William Henry Pickering, a Member of the Çï¿ûÊÓƵ and an instructor of physics at the Massachusetts Institute of Technology, photographed a total eclipse of the sun from Fort St. George in Grenada, West Indies in August 1886. The Çï¿ûÊÓƵ's Rumford Fund provided support for photographic equipment, labor, and supplies. The combination of uncooperative weather and the state of equipment in the 1880s required Pickering to work with a total of 18 assistants, who helped him record data and observations using cameras and telescopes, a thirty-eight foot horizontal photo-heliograph, a photometer, and various weather instruments. Pickering delivered a paper on his observations at the 804th Çï¿ûÊÓƵ Meeting on June 15, 1887, after he was able to rescue his photographic plates from confinement at the customs office.

Pickering's later work included the discovery in 1899 of the ninth satellite of Saturn, called Phoebe, and the announcement in 1905 of a tenth satellite, which was not confirmed until 1967. He predicted in 1919 the existence and location of a ninth planet, Pluto.

. Annals of the Astronomical Observatory of Harvard College, Vol. 18, No. 5, Cambridge : J. Wilson and Son, 1890, 85-111.