Bell, Alexander Graham (1847- ), American inventor and physicist, son of Alexander Melville Bell, was born in Edinburgh, Scotland, on the 3rd of March 1847. He was educated at the university of Edinburgh and the university of London, and removed with his father to Canada in 1870. In 1872 he became professor of vocal physiology in Boston University. In 1876 he exhibited an apparatus embodying the results of his studies in the transmission of sound by electricity, and this invention, with improvements and modifications, constitutes the modern commercial telephone. He was the inventor also of the photophone, an instrument for transmitting sound by variations in a beam of light, and of phonographic apparatus. Later, he interested himself in the problem of mechanical flight. He published many scientific monographs, including a memoir on the formation of a deaf variety in the human race.