On February 14, 1876, Alexander Graham Bell filed an application covering “the method of, and apparatus for, transmitting vocal sounds telegraphically” with the U.S. Patent Office. Two hours later that same day, Elisha Gray filed a patent on a device that would send speech by wire.
By that two-hour gap, Bell became the first person to register a claim for a patent on the telephone. U.S. Patent No. 174,465 eventually became known as “the single most valuable patent ever issued in the history of the world”.
Bell was fascinated with the mechanics of speech from a very young age as his mother was deaf. When he was 19, he realized that there was a relationship between vowel sounds and musical notes. His research of the use of tuning forks led him to the discovery of German physicist, Hermann von Helmholtz. As Bell told the story, his unfamiliarity with the German language resulted in a "very valuable blunder." Helmholtz had devised the means of reproducing vowel sounds by running an intermittent electric current to an electromagnet situated near tuning forks, which it caused to vibrate. Struggling to real Helmholtz's German, Bell concentrated on the illustrations the physicist included in his book On the Sensations of Tone. He concluded mistakenly that Helmholtz had transmitted vowels by telegraph. Helmholtz had made no such claim, but Bell later claimed that had he understood that, "I might never have commenced my experiments."