John Mauchly

Mauchly was born August 30, 1907, in Cincinnati, Ohio, the son of a physicist at the Carnegie Institution whose work took the family to Chevy Chase, Maryland. At McKinley Technical High School he ran the debate team and edited the school paper, then won an engineering scholarship to Johns Hopkins and switched to physics once he got there. He never finished the undergraduate degree, but Johns Hopkins let him go straight through to a physics doctorate, awarded in 1932. The following year he took a teaching post at Ursinus College outside Philadelphia, where for nearly a decade he was the entire physics department, with no reason yet to expect that a defense-training course he signed up for in the summer of 1941 would change what the word computer meant.

Mauchly's 1942 memo proposing a general-purpose electronic calculator became, after the Army signed on in 1943, ENIAC, a machine that could do in one second what took a roomful of human computers all day, built with Eckert handling the hardware while Mauchly worked out what it should compute. Their next design, EDVAC, drew in the mathematician John von Neumann, whose famous "First Draft" report circulated in 1945 with Eckert's and Mauchly's names stripped out by the officer who distributed it. The two men resigned over patent rights in 1946, started their own company, and built UNIVAC, the first computer sold for general business use. Mauchly also wrote Short Code, the first programming language actually run on a computer, and hired Grace Hopper to build UNIVAC's compiler, the software side of the invention, overshadowed by the machine itself.

Mauchly's first wife, Mary Augusta Walzl, a mathematician herself, drowned in 1946, the same year he and Eckert left the university to build the company that made them famous. The business struggled from the start: the National Bureau of Standards contract for UNIVAC ran over budget and over schedule, and by 1950 the Eckert-Mauchly Computer Corporation was insolvent enough that its founder had to sell it to Remington Rand to survive. The larger blow came later. The ENIAC patent, granted in 1964 after a seventeen-year wait, was thrown out by a federal court in 1973, which ruled that its essential ideas had come from Iowa physicist John Atanasoff's earlier, little-known machine. Mauchly spent his last years publicly celebrated as ENIAC's co-inventor while a federal court had, on paper, ruled that he had invented nothing at all.

Mauchly died January 8, 1980, in Ambler, Pennsylvania, during heart surgery. Historians have since pulled the 1973 patent ruling apart: the Atanasoff-Berry Computer was binary and stored data on rotating drums, ENIAC was decimal and stored nothing, and most specialists now treat the two machines as separate inventions rather than one stolen from the other. The Association for Computing Machinery, which Mauchly helped found and once led, and the National Inventors Hall of Fame, which inducted him in 2002, both settled the question the way engineering history usually does, not with a verdict but by crediting everyone. His second wife, Kathleen McNulty, one of ENIAC's six original programmers, spent her later years making sure that work was remembered too.

John Mauchly's life against the full span of the corpus.

• ENIAC invention
  Built with J. Presper Eckert; the first general-purpose electronic digital computer 1945
• EDVAC design invention
  Introduced stored-program concepts, developed with John von Neumann's input 1945
• Eckert-Mauchly Computer Corporation company
  Founded with J. Presper Eckert; sold to Remington Rand in 1950 1947
• Short Code invention
  The first programming language actually used on a computer 1949
• UNIVAC I invention
  First computer built for general business and government use 1951

• August 30, 1907 aged 0 Born in Cincinnati, Ohio
• 1932 aged ~25 Earns a physics doctorate at Johns Hopkins without an undergraduate degree
• Summer 1941 aged ~34 Meets J. Presper Eckert at a Moore School defense-training course
• April 1943 aged 35 The Army contracts the Moore School to build ENIAC
• February 14, 1946 aged 38 ENIAC is unveiled to the public
• 1947 aged ~40 Founds the Eckert-Mauchly Computer Corporation
• 1950 aged ~43 Sells the struggling company to Remington Rand
• October 1973 aged 66 A federal court voids the ENIAC patent, crediting Atanasoff-Berry prior art
• January 8, 1980 aged 72 Dies in Ambler, Pennsylvania, during heart surgery

• J. Presper Eckert 1919–1995
  Co-inventor of ENIAC and pioneer of electronic computing alongside John Mauchly. co-invented ENIAC with
• John Atanasoff 1903–1995
  Physicist who built the first electronic digital computer, the Atanasoff-Berry Computer. patent invalidated in favor of
• John von Neumann 1903–1957
  Hungarian-American mathematician and engineer whose computer architecture remains the basis of modern computing. credit dispute over the EDVAC report
• Grace Hopper 1906–1992
  Computer scientist and Navy rear admiral who helped develop early programming languages and computing. hired to build the UNIVAC compiler