John Mauchly
More info
- Born
- Died
- Known for
- ENIAC, UNIVAC I, Short Code
- Nationality
- American
The physicist whose memo about vacuum-tube calculators became ENIAC — and whose five days in Iowa in 1941 later cost him the patent.
Mauchly taught physics at Ursinus College and built simple counting circuits there to chew through weather data. The motive was meteorological: he was hunting for cycles in decades of observations, and the arithmetic was what set the limit. In June 1941 he spent five days with John Atanasoff in Ames and saw the Atanasoff-Berry Computer up close. Precisely what he took away with him was settled thirty-two years later by a court in Minneapolis.
In August 1942 he wrote the memorandum The Use of High Speed Vacuum Tube Devices for Calculating at the Moore School. It sat ignored until the Army realised the ballistics tables for Aberdeen could not be computed by hand in time, and in 1943 he and Eckert got the ENIAC contract. The division of labour was clean: Mauchly wanted the machine, Eckert knew how to build it.
After the war came EDVAC, the company of their own, BINAC and UNIVAC. In 1949 he also wrote Short Code, an interpreted notation that let expressions be written roughly like mathematics instead of like machine code. Slow, but pointing the right way.