This Day in Geek History: January 17
1882
Leroy B. Firman receives the first patent for a telephone switchboard. (U.S. No. 252,576) The invention will play a fundamental role in the success of the telephone industry.
Thomas Edison is issued a patent for the carbon microphone for the telephone. (US No. 252,442) The microphone consists of a conducting material, such as carbon, held between metal cups or rings attached to the telephone mouthpiece’s diaphragm. Sound waves cause the diaphragm to change the pressure on the carbon button, which, in turn, causes variation in the electric current passing through the carbon button. The variations correspond to the amplitude and pitch of whatever sound is passing through the mouthpiece.
1938
Howard Aiken submits a formal proposal for the construction of an automatic calculating machine, later known as the Harvard Mark I, to Havard University President J.B. Conant. The proposal includes a history of the computers built by Charles Babbage and Herman Hollerith and a discussion of the features that would be required in a machine intended for scientific calculations.
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The United States government’s automated air defense system, the