Kay McNulty

Kay McNulty — born Kathleen Rita McNulty (12 February 1921 – 20 April 2006), later Antonelli and Mauchly — was an Irish-born American mathematician and one of the six original programmers of ENIAC.

Life

McNulty was born in Creeslough, County Donegal, Ireland, and emigrated to Philadelphia as an infant on the night she was baptized — the family left so quickly the story became family legend. Raised in Chestnut Hill, she excelled in mathematics at Chestnut Hill College, graduating in 1942 — one of only a handful of math majors in her class.

Like most of the ENIAC six, she was recruited as a human "computer" by the Army's Ballistic Research Laboratory, grinding out artillery firing tables by hand — work she later described as mind-numbing. When the Army called for volunteers for a secret machine project in 1945, McNulty said yes without being told what the machine was. It was ENIAC.

ENIAC and after

On ENIAC, McNulty worked on the machine's function tables and program structure — she was particularly influential in developing subroutines: the idea that a block of wiring-and-switch logic could be invoked, reused, and checked as a unit. Debugging ENIAC's timing quirks — where a signal arriving a microsecond off produced garbage — was largely her territory.

In 1948 she married ENIAC's co-inventor John Mauchly (his second marriage; they had five children together) and continued working alongside him on the BINAC and UNIVAC projects in a programming capacity — then later took up software for the next generation of Mauchly machines and taught programming at her own kitchen table.

Legacy

• Inducted into the Women in Technology International Hall of Fame with the other five ENIAC programmers in 1997.
• The digital-computer learning center at her Irish hometown's college is named for her — Donegal claims her back.
• She lived to see the ENIAC six publicly recognized, appearing in interviews and the documentary The Computers before her death in 2006.

See also

• The first programmers
• History of Programming

References

1. Kleiman, Kathy. Proving Ground: The Untold Story of the Six Women Who Programmed the World's First Modern Computer (Grand Central, 2022).
2. Haigh, Thomas, Mark Priestley, and Crispin Rope. ENIAC in Action: Making and Remaking the Modern Computer (MIT Press, 2016).
3. Evans, Claire L. Broad Band: The Untold Story of the Women Who Made the Internet (Portfolio, 2018).
4. Honeywell v. Sperry Rand, 180 U.S.P.Q. 673 (D. Minn. 1973) — the ENIAC patent trial.