Communication

Telephone and Multiple Telegraph

When Bell began experimenting with electrical signals, the telegraph had been an established means of communication for some 30 years.

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.

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 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.

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.

By 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.

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.

Bell proceeded with his work on the multiple telegraph, but he did not tell Hubbard that he and Thomas Watson,
a young electrician whose services he had enlisted, were also exploring an idea that had occurred to him that summer - t
hat of developing a device that would transmit speech electrically. Original drawing of the telephone

Source: Library of Congres