Alexander Graham Bell (1847-1922), seen at the opening of the New York-Chicago telephone line in 1892. Bell was born into a family which was keenly interested in the study of sound. His grandfather taught elocution, and his father was a speech therapist. Bell himself eventually became professor of vocal physiology at Boston in 1873. Bell's first successful experiment with his 'telephone' took place on 10 March 1876. He had been granted a patent for the device earlier in the same year, and exhibited it for the first time in Philadelphia. The Bell Telephone Company (now known as AT&T) was founded in 1876.