Tech History Today – Mar. 12

In 1790 – John Frederic Daniell was born. He would grow up to invent the Daniell cell, a battery that supplied an even current during continuous operation, thus making battery power practical.

In 1889 – Almon B. Strowger of Kansas City filed his patent for the first automatic telephone exchange.

In 1923 – Inventor Lee De Forest demonstrated The Phonofilm for the press. It was the first motion picture with a sound-on-film track.