DOLBEAR, Amos Emerson, physicist, born in Norwich, Connecticut, 10 November 1837. He was graduated at Wesleyan University, Delaware, Ohio, in 1866, and with the degree of M. E. at the University of Michigan in 1867, where he received the degree of Ph.D. in 1883. In 1866'7 he was instructor of chemistry at the University of Michigan, and in 1867'8 assistant professor of natural sciences in the University of Kentucky in Lexington. From 1.868 till 1874 he was professor of natural sciences in Bethany College, W. Virginia, and mayor of that City during 1871'2. In 1874 he was appointed professor of physics and astronomy in Tuft's College, College Hill, Massachusetts He has made valuable contributions to science. Among the inventions that he has perfected are the electric gyroscope, used to demonstrate the rotation of the earth, in 1867 ; tuning forks, for the exhibition of Lissajou's curves, in 1872" and the opeidoscope, for the exhibition of vocal vibrations. In 1873 he began to study the convertibility of sound into electricity, and in 1876 perfected and patented his magneto electric telephone, and the static telephone in 1879. He has published " The Art of Projecting " (Boston, 1876); "The Speaking Telephone" (1877); and " Sound and its Phenomena " (1885).