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The History of the Telephone

Alexander Graham Bell, Elisha Gray and the invention of the telephone

In the 1870s, two inventors Elisha Gray and Alexander Graham Bell both independently designed devices that could transmit speech electrically (the telephone). Both men rushed their respective designs to the patent office within hours of each other, Alexander Graham Bell patented his telephone first. Elisha Gray and Alexander Graham Bell entered into a famous legal battle over the invention of the telephone, which Bell won.

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.

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 - that of developing a device that would transmit speech electrically.


Model of Alexander Graham Bell's Telephone

This model of Bell's first telephone (right) is a duplicate of the instrument through which speech sounds were first transmitted electrically (1875).

While Alexander Graham Bell and Thomas Watson worked on the harmonic telegraph at the insistent urging of Hubbard and other backers, Bell nonetheless met in March 1875 with Joseph Henry, the respected director of the Smithsonian Institution, who listened to Bell's ideas for a telephone and offered encouraging words. Spurred on by Henry's positive opinion, Bell and Watson continued their work. By June 1875 the goal of creating a device that would transmit speech electrically was about to be realized. They had proven that different tones would vary the strength of an electric current in a wire. To achieve success they therefore needed only to build a working transmitter with a membrane capable of varying electronic currents and a receiver that would reproduce these variations in audible frequencies.

On June 2, 1875, Alexander Graham Bell while experimenting with his technique called "harmonic telegraph" discovered he could hear sound over a wire. The sound was that of a twanging clock spring.

Bell's greatest success was achieved on March 10, 1876, marked not only the birth of the telephone but the death of the multiple telegraph as well. The communications potential contained in his demonstration of being able to "talk with electricity" far outweighed anything that simply increasing the capability of a dot-and-dash system could imply.

Alexander Graham Bell's notebook entry of 10 March 1876 describes his successful experiment with the telephone. Speaking through the instrument to his assistant, Thomas A. Watson, in the next room, Bell utters these famous first words, "Mr. Watson -- come here -- I want to see you."

Born on March 3, 1847, in Edinburgh, Scotland, Alexander Graham Bell was the son and grandson of authorities in elocution and the correction of speech. Educated to pursue a career in the same specialty, his knowledge of the nature of sound led him not only to teach the deaf, but also to invent the telephone.

Bell's unceasing scientific curiosity led to invention of the photophone, to significant commercial improvements in Thomas Edison's phonograph, and to development of his own flying machine just six years after the Wright Brothers launched their plane at Kitty Hawk. As President James Garfield lay dying of an assassin's bullet in 1881, Bell hurriedly invented a metal detector in an unsuccessful attempt to locate the fatal slug.

Alexander Graham Bell - Biography
In 1876, at the age of 29, Alexander Graham Bell invented his telephone. Bell might easily have been content with the success of his invention. His many laboratory notebooks demonstrate, however, that he was driven by a genuine and rare intellectual curiosity that kept him regularly searching, striving, and wanting always to learn and to create.




Telephone History - Telephone Technology
Service Lines and Switchboards

In 1877, construction of the first regular telephone line from Boston to Somerville, Massachusetts was completed. By the end of 1880, there were 47,900 telephones in the United States. The following year telephone service between Boston and Providence had been established. Service between New York and Chicago started in 1892, and between New York and Boston in 1894. Transcontinental service by overhead wire was not inaugurated until 1915. The first switchboard was set up in Boston in 1877. On January 17, 1882, Leroy Firman received the first patent for a telephone switchboard.

Exchanges and Rotary Dialing

The first regular telephone exchange was established in New Haven in 1878. Early telephones were leased in pairs to subscribers. The subscriber was required to put up his own line to connect with another. In 1889, Almon B. Strowger a Kansas City undertaker, invented a switch that could connect one line to any of 100 lines by using relays and sliders. This switch became known as "The Strowger Switch" and was still in use in some telephone offices well over 100 years later. Almon Strowger was issued a patent on March 11, 1891 for the first automatic telephone exchange.

The first exchange using the Strowger switch was opened in La Porte, Indiana in 1892 and initially subscribers had a button on their telephone to produce the required number of pulses by tapping. An associate of Strowgers' invented the rotary dial in 1896 which replaced the button. In 1943, Philadelphia was the last major area to give up dual service (rotary and button).

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