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THE AMERICAN NATURALIST 



■[Vol. LVI 



1st pres. Appalachian Mountain Club; mem. Century Assn., l^ew 

 York. Author: Elements of Physical Manipulation, and 60 volumes 

 of annals and other publications of Harvard Coll. Observatory. 

 Address: Harvard Observatory, Cambridge, Mass. 



Account given in Appleton's Cyclopedia of American 

 Biography, 1887-8 

 Pickering, Edward Charles, astronomer, b. in Boston, Mass., 19 

 July, 1846, was graduated in civil engineering course at the Law- 

 rence scientific school of Harvard in 1865. During the following year 

 he was called to the Massachusetts institute of technology as assistant 

 director of physics, of which branch he held the full professorship 

 from 1868 till 1877. Prof. Pickering devised plans for the physical 

 laboratory of the institution, and introduced the experimental method 

 of teaching physics at a time when that mode of instruction had not 

 been adopted elsewhere. His scientific work of these years consisted 

 largely of researches in physics, notably investigations on the polari- 

 zation of light and the laws of its reflection and dispersion. He also 

 described a new form of spectrum telescope, and invented in 1870 a 

 telephone receiver, which he publicly exhibited. He observed the 

 total eclipse of the sun on 7 Aug., 1869, with the party that was sent 

 out by the Nautical almanac office, at Mt. Pleasant, Iowa, and was a 

 member of the U. S. coast survey expedition to Xeres, Spain, to 

 observe that of 22 Dec, 1870, having, on that occasion, charge of 

 the polariscope. In 1876 he was appointed professor of astronomy 

 and geodesy, and director of the observatory at Harvard, and under 

 his management this observatory has become one of the foremost in 

 the United States. More than twenty assistants now take part in 

 investigations under his direction and the invested funds of the 

 observatory have increased from $176,000 to $654,000 during his 

 administration. His principal work since he accepted this appoint- 

 ment has been the determination of the relative brightness of the 

 stars, which is accomplished by the means of a meridian photometer, 

 an instrument specially devised for this purpose, and he has prepared 

 a catalog giving the brightness of over 4,000 stars. Since 1878 he 

 has also made photometer measurements of Jupiter's satellites while 

 they are undergoing eclipse, and of the satellites of Mars and other 

 faint objects. On the death of Henry Draper (q.v.) his widow re- 

 quested Prof. Pickering to continue important researches on the ap- 

 plication of photography to astronomy, as a Henry Draper memorial, 

 and the study of the spectra of the stars has been undertaken on a 

 scale that was never before attempted. A fund of $250,000, left by 

 Uriah A. Boyden (q.v.) to the observatory, has been utilized for the 

 special study of the advantages of very elevated observing stations. 

 Prof. Pickering has also devoted attention to such objects as moun- 

 tam surveymg, the height and velocity of clouds, papers on which he 



