The First Telephone
Bell invented the telephone while trying to improve the telegraph, which was limited to sending one message at a time. Bell believed that multiple messages could be sent over a wire if the sounds had a different pitch, which is how the ear responds to the frequency of the sound waves.
In October 1874, Bell was working on his "harmonic telegraphic" when he received financial backing from Boston attorney Gardiner Greene Hubbard, who was also Bell’s future father-in-law. Bell, Hubbard and Thomas Sanders, the wealthy father of one of Bell’s former students, formed the Bell Telephone Company, which led to the development of the American Telephone and Telegraph Company – AT&T.
By June 1875, Bell and Watson proved that the strength of an electrical current over a wire could vary depending on the tone of the sounds. They just needed to build a transmitter that could send varying electronic currents and a receiver that could reproduce the variations in frequencies. The first telephone call occurred on March 10, 1876. Bell and Watson were in their Boston lab in separate rooms. Bell spoke into the mouthpiece of his new invention and said, “Watson, come here. I want to see you." They switched places and Watson read from a book while Bell listened. The words were not clear and crisp, but it was the end of the telegraph and the beginning of the telephone. The first long distance call occurred in 1892 when Bell called Chicago from New York. The price for a long distance call was $9 for the first five minutes.
Bell did not stop with the telephone. In 1880 he invented the photophone, which transmitted sound on a beam of light and was the precursor to fiber optics, which revolutionized telecommunications in the 20th century.