Hubbard, who resented the absolute control then exerted by the Western Union Telegraph Company, instantly saw the potential for breaking such a monopoly and gave Bell the financial backing he needed. Prints and Photographs Division, Library of Congress.īy October 1874, Bell's research had progressed to the extent that he could inform his future father-in-law, Boston attorney Gardiner Greene Hubbard, about the possibility of a multiple telegraph. 'This model of Bell's first telephone is a duplicate of the instrument through which speech sounds were first transmitted electrically, 1875' on phone. His 'harmonic telegraph' was based on the principle that several notes could be sent simultaneously along the same wire if the notes or signals differed in pitch. Although the idea of a multiple telegraph had been in existence for some time, Bell offered his own musical or harmonic approach as a possible practical solution. Bell's extensive knowledge of the nature of sound and his understanding of music enabled him to conjecture the possibility of transmitting multiple messages over the same wire at the same time. Although a highly successful system, the telegraph, with its dot-and-dash Morse code, was basically limited to receiving and sending one message at a time. When Bell began experimenting with electrical signals, the telegraph had been an established means of communication for some 30 years. Sketches, undated handwritten text top and bottom of page, 1876.īox 273, 'Subject File: The Telephone-Drawing of the Telephone, Bell's Original.'Īlexander Graham Bell Family Papers, Manuscript Division, Library of Congress. Alexander Graham Bell's design sketch of the telephone. The telegraph and telephone are both wire-based electrical systems, and Alexander Graham Bell's success with the telephone came as a direct result of his attempts to improve the telegraph. Listen to this page Telephone and Multiple Telegraph

Harmonic telegraph how does it work