Women in the History of Computing Technology

Frances Bilas remains in the history of computing technology as one of the six original programmers of the Electronic Numerical Integrator and Computer (ENIAC), the first general-purpose electronic digital computer.

Frances Bilas Spence was born in Philadelphia in 1922. Initially she attends Temple University but once being awarded a scholarship, she transfers to Chestnut Hill College, from where she graduates in 1942 with a degree in mathematics and a minor in physics.

It is in Chestnut Hill College that Frances first meets Katheleen McNulty, another woman that later becomes an ENIAC programmer. Shortly after their graduation, they are both hired by the U.S. Army and start working as human “computers” in a large classroom at the Moore School of Electrical Engineering, University of Pennsylvania; the same place where the ENIAC itself is built and further operated until December, 1946. Their initial work is focused on computing ballistics trajectories used primarily for artillery firing tables. As a result of their excellent performance, after two or three months, they are moved to work on the differential analyzer, the largest and most sophisticated analog mechanical calculator of that time, known for its capacity to make a single trajectory computation, which takes approximately 40 hours of work on a mechanical desk calculator, in about 50 minutes. Later, once the ENIAC is built for the purpose of executing the same calculations, they are both selected to join its original group of programmers.

Initially, the ENIAC is a classified project and, therefore, the programmers are not allowed to enter the room where the machine is located. Instead, they are given access to different blueprints they can use to develop programs while working in an adjacent room. The programming itself involves discretizing the differential equations involved in a ballistic trajectory problem to the precision allowed by the ENIAC and calculating the path to the appropriate bank of electronics in parallel progression, with each separate instruction having to reach the correct location in time to within 1/5,000th of a second. After working out a program on paper, the women are allowed to enter the ENIAC room and actually program the machine.

In 1947, the ENIAC computer is moved to the Aberdeen Proving Ground’s Ballistics Research Laboratory and Fran Bilas, along with Kay McNulty and Ruth Lichterman, another pioneer programmer, is transferred there in order to continue working on it. It is Aberdeen that she meets her future husband, Homer Spence, an Army electrical engineer, who is also assigned to the ENIAC project and who later becomes head of the Computer Research Branch. They marry in 1947. Shortly after that, Frances resigns her job to raise her family.

In 1997, Frances Bilas Spence is inducted into the Women in Technology International Hall of Fame, along with the other five original ENIAC programmers (Katheleen McNulty Antonelli, Betty Snyder Holberton, Betty Jean Jennings Bartik, Marlyn Wescoff, and Ruth Lichterman).

Sources

The information presented above is taken from the following online sources:

• -- Frances Spence (Wikipedia, the Free Encyclopedia)
• -- ENIAC (Wikipedia, the Free Encyclopedia)
• -- Kathleen Antonelli (Wikipedia, the Free Encyclopedia)
• -- Frances Spence (Absolute Astronomy)