In june, bell demonstrated the telephone for sir william thomson (baron kelvin) and emperor pedro ii of brazil at the centennial exhibition in philadelphia. On july 9, 1877, bell, hubbard, sanders, and … Alexander graham bell (march 3, 1847 †august 2, 1922) was a scottish scientist, inventor, and innovator.

After inventing the telephone, bell continued his experiments in communication, which culminated with the photophone transmission of sound on a beam of light, a precursor of today's optical fiber …