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John Mauchly (1907–1980)

Basic Facts

  • Full name: John William Mauchly
  • Born: 30 August 1907, Cincinnati, Ohio
  • Died: 8 January 1980, Ambler, Pennsylvania
  • Cause of death: Heart surgery complications following long illness

Family Background

Born to Sebastian and Rachel (Scheidemantel) Mauchly, of German descent. Had a sister, Helen Elizabeth (Betty). His father was a physicist at the Carnegie Institution of Washington’s Department of Terrestrial Magnetism. The family moved to Chevy Chase, Maryland when his father obtained his position at Carnegie.

Education

  • Elementary: E.V. Brown Elementary School, Chevy Chase
  • High school: McKinley Technical High School, Washington, D.C. (graduated 1925). Active in debate, national honor society, editor-in-chief of Tech Life.
  • Undergraduate: Johns Hopkins University on an engineering scholarship; transferred to physics.
  • Ph.D.: Physics from Johns Hopkins, 1932.

Career Timeline

Early Career (1932–1941)

  • 1932–1933: Research assistant at Johns Hopkins, studying formaldehyde spectrum energy levels.
  • 1933: Appointed head of the physics department at Ursinus College (he was the sole staff member). Here he developed an interest in statistical methods for weather prediction, which led him toward computing.
  • Summer 1941: Took a Defense Training Course in Electronics at the University of Pennsylvania’s Moore School of Electrical Engineering. Met J. Presper Eckert, a lab instructor, forming what would become a “long-standing working partnership.”
  • 1941–1943: Hired as instructor at the Moore School; promoted to assistant professor of electrical engineering.

ENIAC (1942–1946)

  • 1942: Wrote a memo proposing a general-purpose electronic computer, emphasizing the “enormous speed advantage” of electronics over mechanical relay systems.
  • June 1943: Together with Herman Goldstine, secured Army funding for the ENIAC project. The Army contracted the Moore School to build it.
  • Role: Mauchly led the conceptual design; Eckert led the hardware engineering.
  • Performance: ENIAC was roughly 1000 times faster than existing technology. It could add 5000 numbers or perform 357 ten-digit multiplications per second.
  • 1948: ENIAC was redesigned to allow stored programs.

The Atanasoff Controversy

  • June 1941: Mauchly visited John Vincent Atanasoff’s laboratory at Iowa State College and spent several days studying the Atanasoff-Berry Computer (ABC). He had complete access to the machine and its documentation.
  • Mauchly’s account: He credited his inspiration to high-speed electronic flip-flops in cosmic-ray counting devices at Swarthmore College, not to Atanasoff’s machine.
  • October 1973: In the landmark case Honeywell v. Sperry Rand, a federal court invalidated the ENIAC patent (U.S. Patent 3,120,606, filed 26 June 1947, issued 4 February 1964), ruling that “the subject matter of one or more claims of the ENIAC was derived from Atanasoff.” The decision remains controversial: the ABC was a special-purpose device using binary arithmetic and drum memory, while ENIAC was a general-purpose machine using decimal decade counters.

EDVAC and the “First Draft” Controversy

  • 1944: ENIAC design frozen for construction; the team began considering a successor.
  • January 1945: Secured contract for EDVAC (Electronic Discrete Variable Automatic Computer).
  • Eckert’s key innovation: Proposed mercury delay-line memory for storing both programs and data.
  • Von Neumann’s role: Joined the engineering discussions at the Moore School in 1944; produced the “First Draft of a Report on the EDVAC” (distributed 30 June 1945).
  • The controversy: Herman Goldstine distributed the report listing von Neumann as sole author, removing any reference to Eckert or Mauchly. This gave von Neumann sole credit for the stored-program concept. Eckert and Mauchly contended that the concept had been discussed within the Moore School team at least eight months before von Neumann’s involvement.

Moore School Lectures (1946)

  • March 1946: The Moore School changed its patent policy; Mauchly and Eckert resigned in protest.
  • 8 July – 31 August 1946: The Moore School hosted “The Theory and Techniques for Design of Digital Computers,” a landmark summer course. Mauchly delivered six of the lectures. Attendees came from the Army, Navy, MIT, NBS, Cambridge, Columbia, Harvard, IAS, IBM, Bell Labs, Kodak, GE, and NCR. The lectures disseminated computing knowledge broadly and are considered a pivotal event in computing history.

Eckert-Mauchly Computer Corporation (1947–1950)

  • 1947: Founded the first computer company with Eckert. Mauchly served as president.
  • Received a contract from the National Bureau of Standards to build UNIVAC (originally called “EDVAC II”).
  • UNIVAC: The first computer designed for business applications; featured magnetic tape for mass storage.
  • Interim product: BINAC (Binary Automatic Computer).
  • 1950: The company ran into financial troubles and was purchased by Remington Rand, becoming the UNIVAC division. Mauchly became Director of Applications.

Software Innovation

  • 1949: Created Short Code, the first programming language actually used on a computer.
  • Hired Grace Murray Hopper to develop the UNIVAC compiler.
  • His 1942 paper contains the first documented use of the verb “to program” in an electronic computing context.

Later Career

  • 1959: Left Sperry Rand; founded Mauchly Associates, Inc.
  • Developed the Critical Path Method (CPM) for automated construction scheduling.
  • 1967: Established Dynatrend consulting organization.
  • 1973–1980: Consultant to Sperry UNIVAC until his death.

Personal Life

  • First marriage: Mary Augusta Walzl (mathematician), 30 December 1930. Children: James (Jimmy) and Sidney. Mary drowned in 1946.
  • Second marriage: Kathleen (Kay) McNulty (1948), one of the six original ENIAC programmers. Married “against the wishes of her parents.” Children: Sara (Sallie), Kathleen (Kathy), John, Virginia (Gini), Eva. The family lived in Philadelphia and later at Little Linden farmhouse in Ambler, Pennsylvania.

Awards and Honors

  • Life member: Franklin Institute, National Academy of Engineering, Society for Advancement of Management
  • Fellow: IRE (1957, predecessor to IEEE)
  • Fellow: American Statistical Association
  • Honorary degrees: LLD from University of Pennsylvania; DSc from Ursinus College
  • Harry H. Goode Memorial Award (1966)
  • Harold Pender Award (1973)
  • IEEE Emanuel R. Piore Award (1978)
  • Philadelphia Award, Scott Medal, AFIPS Goode Medal, Pennsylvania Award
  • Inducted posthumously into National Inventors Hall of Fame (2002)

Professional Leadership

  • Founding member and president of the Association for Computing Machinery (ACM)
  • Co-founder of the Society for Industrial and Applied Mathematics (SIAM); served as its fourth president

Connections to Others in the Story

  • J. Presper Eckert: Engineering partner for ENIAC, EDVAC, BINAC, and UNIVAC. Co-founded the first computer company.
  • John von Neumann: Consultant to the ENIAC project; the “First Draft” controversy over the stored-program concept created lasting bitterness.
  • Herman Goldstine: Army liaison who helped secure ENIAC funding; distributed the “First Draft” under von Neumann’s name alone.
  • Kay McNulty (Kathleen Antonelli): Second wife; one of the six ENIAC programmers.
  • Adele Goldstine: Trained the ENIAC programmers; wrote the technical manual.
  • John Vincent Atanasoff: Creator of the ABC; the 1973 court ruling found ENIAC patent claims were derived from his work.

Sources