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Alumna one of the mothers of modern-day computer programming

Alumna one of the mothers of modern-day computer programming

Kathleen "Kay" McNulty's graduation photo from Chestnut Hill College. (Photo courtesy of Gini Calcerano)by Katie Kohler

For children in the 1950s, family dinners were an everyday occurrence. The American institution was mostly undisturbed by late nights at the office, after-school activities, and buzzing phones.

Family dinners were much different in the home of Gini Mauchly Calcerano, senior director of research and data management at Chestnut Hill College. Instead of usual mealtime banter, the talk revolved around computers.

Before computers were as ubiquitous in the home as kitchen tables, these types of discussions weren’t exactly common; however, for Calcerano, her mother and father weren’t just parents to seven children — they were also the proverbial mother and father of one of the biggest inventions of all time.

Calcerano’s father, John Mauchly, invented the Electronic Numerical Integrator and Computer, known as the ENIAC, the first electronic general-purpose computer. And her mother, Kathleen “Kay” McNulty ’42, is considered one of the mothers of modern-day computer programming.

“There were always discussions about computers,” Calcerano recalled. “My father frequently had dinner guests who worked with him. It was just normal dinnertime discussion, normal life. When I was in grade school, my mother and father were going to awards banquets where my father was getting various awards for his work. We knew my mother was involved, but she didn’t make a big deal of it.”

At the time, no one was making a “big deal” of McNulty’s work. It wasn’t until 1997, 51 years after the ENIAC was developed, that anyone paid attention to female programmers’ contributions. This recognition was the result of research conducted by Harvard University student and programmer Kathy Kleiman. In her thesis, Kleiman demonstrated the importance of the ENIAC programmers and women pioneers in early programming.

“It’s bittersweet in a way. She did get to see some of it,” said Calcerano of her mother’s delayed recognition.

The ENIAC was unveiled in February 1946, and McNulty died in 2006, but recently there has been a buzz of positive activity commemorating her work.

In celebration of International Women’s Day on March 8, Tesco Ireland partnered with the Women’s Museum of Ireland to display special installations in Tesco stores that showcase six of Ireland’s historic female figures and their pioneering contributions to society.

“We’re inspired every day by the women across the country who work and shop in our stores and hope to inspire the next generation by telling the somewhat unknown stories of inspirational women of Irish history,” said Ruairi Twomey, the marketing director for Tesco Ireland, in an article published in The Irish Examiner.

In April, the Irish American Heritage Foundation will induct McNulty into its Hall of Fame, along with a class that includes the late U.S. Senator John McCain.

McNulty was born Feb. 12, 1921, in Creeslough, County Donegal, Ireland, during the Irish War of Independence. When she came to the United States as a young girl, she only spoke Gaelic until she started school at Our Mother of Consolation.

At the College, McNulty was one of only three women to graduate with a bachelor’s degree in mathematics. Upon graduation in 1942, she was employed by the U.S. Army at the University of Pennsylvania’s Moore School of Engineering as a human “computer” to help with the American war effort during World War II. McNulty, and about 75 other women with similar roles, calculated tables of trajectories for shells and bullets, which soldiers needed to accurately aim artillery.

“We did have desk calculators at that time, mechanical and driven with electric motors, that could do simple arithmetic,” McNulty said, describing the work she did preparing firing tables for guns. “You’d do a multiplication and when the answer appeared, you had to write it down to reenter it into the machine to do the next calculation. We were preparing a firing table for each gun, with maybe 1,800 simple trajectories.

“To hand-compute just one of these trajectories took 30 or 40 hours of sitting at a desk with paper and a calculator. As you can imagine, they were soon running out of young women to do the calculations. Actually, my title working for the ballistics project was ‘computer.’ The idea was that I not only did arithmetic but also made the decision on what to do next. ENIAC made me, one of the first ‘computers,’ obsolete.”

McNulty was one of six women chosen from the ranks of the computers to work on the top secret project ENIAC, which could calculate at electronic speeds, but needed to be set up by programmers. While working on ENIAC at Penn, she met John W. Mauchly, who, with J. Presper Eckert, had designed the ENIAC. In 1948 she married Mauchly, and two years later they moved to Ambler, where they raised seven children.

Once married with children, McNulty did not work outside of the home, but it didn’t limit her contributions. She continued to discuss ideas with her husband about the computers he developed. She also served as an officer and a treasurer for the companies he founded.

“She jumped into everything. She was a Girl Scout leader and Cub Scout den mother, and she taught us to sew,” Calcerano said. “There was nothing that seemed impossible to her. My father bounced ideas off her all the time. At dinner, many times we had to wait until they were done talking about computer architecture and programming languages before we could talk about anything else.”

After John Mauchly’s death, McNulty was a regular speaker for ENIAC-related and computer history events; however, she spoke of her husband’s work without mentioning her contributions.

“In response to Kathy Kleiman’s efforts, the world learned of the existence and significance of the ENIAC programmers and my mother. Then she went on a speaking circuit discussing women in technology and how involved they were in the early stages of computers,” Calcerano said.

The Irish Center for High-End Computing has a new supercomputer named “Kay.” It is ICHEC's primary supercomputer and Ireland's national supercomputer for academic researchers. Installed at the National University of Ireland, Galway, in August 2018, the machine’s name was chosen by a national popular vote from among the names of several notable Irish scientists. Irish Television is producing a half-hour documentary about the life of McNulty, scheduled to air in January 2020.

While the honors for McNulty continue to come posthumously, her words are forever etched in Calcerano's memory.

“My mother said, ‘There’s always room for the best,’” Calcerano said. “She felt that you should have the confidence that you can do whatever you set your mind on. Other people cannot and should not limit you unless you let them.”

Posted In: Alumni News