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As a young man, Alexander Graham Bell taught deaf students in schools and universities to help them communicate. He was trained in this work by his parents. In 1862, Bell enrolled as a "student teacher" at a boy's school near Edinburgh, Scotland. There he taught music and elocution in exchange for instruction in other subjects. Later, he became a full-time teacher, using Visible Speech in teaching a class of deaf children.

In April, 1871, Bell went to Massachusetts. As a teacher of the deaf, Bell was determined to help deaf people speak, so that they could take part in the speaking world, rather than be isolated and alone. To do this, he tried to find a way to make sound visible.

Bell attempted to simulate the hearing process by tinkering with an invention called the phonautograph. As he was working on the phonautograph the idea for the telephone suddenly occurred to him. Later, Bell and his brothers made a model skull and fitted it with a reproduction of human vocal apparatus that was worked with a bellows.

Bell's first telephone worked very much like his phonautograph, with a few technical improvements. Bell's first telephone patent was issued on March 7, 1876 as US Patent 174465. Three days later, in Boston, the telephone carried its first intelligible sentence. The Bell Patent is reckoned to be the most valuable ever issued. Within a year following commercial application there followed the first of hundreds of legal suits. In a 4-3 decision in 1893 the US Supreme Court upheld Bell's claims in their very broad scope.

Claim 1. A system of telegraphy in which the receiver is set in vibration by the employment of undulatory currents of electricity, substantially as set forth.