has grown the Boston society of natural history. His literary work included, besides various legal papers, " A Report of tin- Trial by Impeachment of James Prescott" with William II. Gardiner (Boston, 1821), and he prepared the first volume of the "Life of Timothy Pickering by his Son" (4 vols., 1867-73), of which the remaining volumes were issued by Charles W. Upham. Timothy's grandson, Charles, physician, b. in Susquehanna county, Pa., 10 Nov., 18"05; d. in Boston, Mass., 17 March. 1878, was graduated at Harvard in 1823, and at its medical department in 1826, after which he settled in the practice of his profession in Philadelphia. Meanwhile he developed interest in natural history and became a member of the Philadelphia academy of natural sciences, to whose transactions he contributed valuable papers. In 1838-'43 he was naturalist to the U. S. exploring expedition under Capt. Charles Wilkes. On his return he was a year in Washington, and then visited eastern Africa, travelling from Egypt to Zanzibar, and thence to India for the purpose of more thoroughly studying the people of those parts of the world t hat had not been visited by the expedition. Nearly two years were occupied in these researches, after which he devoted himself to the preparation of "The Races of Man and their Geographical Distribution" (Boston, 1848), which forms the ninth volume of the " Reports of the U. S. Exploring Expedition," and was republished in "Bohn's Illustrated Library" (London, 1850). This he followed with his "Geographical Distribution of Animals and Man" (1854) and "Geographical Distribution of Plants" (1861). Dr. Pickering was a member of the American oriental society, the American academy of arts and sciences, the American philosophical society, and other learned bodies, to whose proceedings he contributed. At the time of his death he left in manuscript "Chronological History of Plants : Man's Record of his own Existence illustrated through their Names, Uses, and Companionship " (Boston, 1879). Timothy's great-grandson, Edward Charles, astronomer, b. in Boston, Mass., 19 July, 1846, was graduated in the civil engineering course at the Lawrence scientific school of Harvard in 1865. During the following year he was called to the Massachusetts institute of technology as assistant instructor of physics, of which branch he held the full professorship from 1868 till 1877. Prof. Pickering devised plans for the physical laboratory of the institute, and introduced the experimental method of teaching physics at a time when that mode of instruction had not been adopted clseivheiv. His scientific work during these years consisted largely of researches in physics, notably nnestigations on the polarization of light and the laws of its reflection and dispersion. He also described a new form of spectrum telescope, and invented in 1*70 a telephone-receiver, which he publicly exhibited, lie observed the total eclipse of ih<- -tin on 7 Aui, r .. 1869, with the party that was sent out by thr N:n-tical almanac office, at Mount Pleasant. Iowa, and was a member of the U. >. i oasl -urvcy expedition to Xeres, Spain, to observe that of 22 Dec., 1*70, having on that occasion charge of the polan-eopr. 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 $054.000 during his administration. His principal work since he ai-ee|ited this appointment has been the determination of the relative brightness of the stars, which is accomplished by means of a meridian photometer, an instrument which has been specially devised for this purpose, and he has prepared a catalogue giving the brightness of over 4,000 stars. Since 1878 he has also made photometric measurements of Jupiter's satel- lites while they are undergoing eclipse, and of the satellites of Mars and other very faint objects. On the death of Henry Draper (g. i) his widow requested Prof. Pickering to continue important researches on the application of photography to astronomy, as a Henry Draper memorial, and the study of the spectra of the stars by photography has thus been undertaken on a scale that was never before attempted. A fund of |250,000, left by Uriah A. Boyden (g. 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 subjects as mountain-surveying, the height and velocity of clouds, pa- pers on which he has contributed to the Appalachian club, of which he was president in 1877, and again in 1882. He is an associate of the Royal astronomical society of London, from which in 1886 he received its gold medal for photometric researches, and, besides membership in other scientific so- cieties in the L T nited States and Europe, he was elei-ted in 1873 to the National academy of sciences, by which body he was further honored in 1887 with the award of the Henry Draper medal for his work on astronomical physics. In 1876 he was elected a vice-president of the American association for the advancement of science, and presented his retiring address before the section of mathematics and I'tnsirs at the Nashville meeting. In addition to his many papers, which number about 100, he prepared annual "Reports on the Department of Physics "for the Massachusetts institute of technology, and the "Annual Reports of the Director of the Astronomical Observatory," likewise editing the "Annals of the Astronomical Observatory of Harvard College." He has also edited, with note-. " The Theory of Color in its Relations to Art and Art Industry," by Dr. William von Bezold (Boston, 1876), and he is the author of " Elements of Physical Manipulation " (2 parts. Boston, 1873-'6). Edward Charles's brother. William Henry, astronomer, b. in Boston. Mass., 15 Feb., 1858, was graduated at the Massachusetts institute of technology in 1879, and in 1880-'7 was instructor of physics in that institution. In March. 1^7, I he was called to the charge of the Boyden depart- j ment of the Harvard observatory, which plai ' lie i still fills. He founded in 1882, in connection with the Institute of technology, the first regular laboratory where dry-plate photography was systematically taught to numerous pupils. Mr. Pickering observed the solar eclipse of 1878 from Colorado, and in 1886 conducted an expedition to the West Indies to observe the total eclipse of that year. In 1887 he led an expedition to Colorado to make astronomical observations for the purpose of selecting the most suitable site for an astronomical ob- servatory. In addition to various articles on photography in technical periodicals, and the traditions of the Amerirati aeadeins . he has published Walking Guide to the Mount Washington Range" (Boston. ls^-ji.
PICKETT. Albert James, historian, b. in Anson county. X. C., '-> Aug.. isld; d. in Montgomery. Ala., 2M Oct., 1S5S. He removed with his father to Autauga county, Ala., in 1818. and stud- ied law, but never practised his profession, devoting his life to literary pursuits and to the care of
