It was Bell's idea that, by a system of tuning different telegraphic receivers to different pitches, several telegraphic messages could be sent simultaneously over the same wire. The idea was not original with Bell, although he supposed that it was and was entirely unaware that, at the particular moment when he started work, about twenty other inventors were struggling with the same problem. It was one of these other twenty experimenters, Elisha Gray, who ultimately perfected this instrument. Bell's researches have an interest only in that they taught him much about sound transmission and other kindred subjects and so paved the way for his great conception. One day Hubbard and Sanders learned that Bell had abandoned his "harmonic telegraph" and was experimenting with an entirely new idea. This was the possibility of transmitting the human voice over an electric wire. While working in Sanders's basement, Bell had obtained from a doctor a dead man's ear, and it is said that while he was minutely studying and analyzing this gruesome object, the idea of the telephone first burst upon his mind. For years Bell had been engaged in a task that seemed hopeless to most men--that of making deaf-mutes talk. "If I can make a deaf-mute talk, I can make iron talk," he declared. "If I could make a current of electricity vary in intensity as the air varies in density," he said at another time, "I could transmit sound telegraphically." Many others, of course, had dreamed of inventing such an instrument. The story of the telephone concerns many men who preceded Bell, one of whom, Philip Reis, produced, in 1861, a mechanism that could send a few discordant sounds, though not the human voice, over an electric wire. Reis seemed to have based his work upon an article published in "The American Journal of Science" by Dr. C.G. Page, of Salem, Mass., in 1837, in which he called attention to the sound given out by an electric magnet when the circuit is opened or closed. The work of these experimenters involves too many technicalities for discussion in this place. The important facts are that they all involved different principles from those worked out by Bell and that none of them ever attained any practical importance. Reis, in particular, never grasped the essential principles that ultimately made the telephone a reality. His work occupies a place in telephone history only because certain financial interests, many years after his death, brought it to light in an attempt to discredit Bell's claim to priority as the inventor. An investigator who seems to have grasped more clearly the basic idea was the distinguished American inventor Elisha Gray, already mentioned as the man who had succeeded in perfecting the "harmonic telegraph." On February 14, 1876, Gray filed a caveat in the United States Patent Office, setting forth pretty accurately the conception of the electric telephone. The tragedy in Gray's work consists in the fact that, two hours before his caveat had been put in, Bell had filed his application for a patent on the completed instrument.
The champions of Bell and Gray may dispute the question of priority to their heart's content; the historic fact is that the telephone dates from a dramatic moment in the year 1876. Sanders and Hubbard, much annoyed that Bell had abandoned his harmonic telegraph for so visionary an idea as a long distance talking machine, refused to finance him further unless he returned to his original quest. Disappointed and disconsolate, Bell and his assistant, Thomas A. Watson, had started work on the top floor of the Williams Manufacturing Company's shop in Boston. And now another chance happening turned Bell back once more to the telephone. His magnetized telegraph wire stretched from one room to another located in a remote part of the building. One day Watson accidentally plucked a piece of clock wire that lay near this telegraph wire, and Bell, working in another room, heard the twang. A few seconds later Watson was startled when an excited and somewhat disheveled figure burst into his room.