The first typewriter prototype was made with 11 piano keys

Journalist, Christopher Latham Sholes, dabbled in inventions on the side. He and Samuel W. Soulé, a mechanist, developed devices that numbered the pages of blank books. They shared their shop with a third inventor, Carlos Glidden, and the trio used the numbering machine as the basis for a personal lettering machine, now known as the typewriter.

 Original patent application

The patent for their machine was granted in 1868.
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