ENIAC                             U. S. Army

Colonel Paul Gillon -- Grandfather of ENIAC

Paul H. Deitz
29 January, 1996

Those of you who have perused the pages of the ENIAC saga in various books and articles are no doubt aware of the key role played by COL Paul Gillon. Paul Gillon obtained a master's degree at MIT, became executive officer of the Ballistic Research Laboratory (BRL), and when Leslie Simon became the director, Gillon was appointed assistant director. The year was 1939. By 1935, LT Gillon had already displayed a particular interest in computational work and, as World War II was about to begin, realized the great importance of digital computation to the construction of firing and bombing tables. During this period of the late 1930's, COL Gillon reached out to the Moore School of Electrical Engineering at the University of Pennsylvania to strengthen the computing position of the Laboratory. This was a particularly logical connection because of the existence of a Bush Differential Analyzer located at Penn. The BRL had such a device as well, but of lower precision, as a brilliant graduate student, J. Presper Eckert, had made significant improvements to the Penn device by substituting more modern cross-polarized filters and motors in place of bobbins and string.

In the mean time, John Mauchly, a physicist and professor at nearby Ursinus College, was taken with the concept of digital computing. In December 1940, Mauchly gave a paper at the American Association for the Advancement of Science (meeting in Philadelphia) on some research he was doing on calculating devices to aid weather forecasting. John V. Atanasoff, of Iowa State University was in the audience and introduced himself at the end of the talk. Atanasoff mentioned that he was also working on a calculating device. In correspondence that Spring, Mauchly indicated his interest in seeing Atanasoff's machine, and in June, Mauchly drove to Ames Iowa where he was shown the machine, later dubbed the ABC (Atanasoff Berry Computer- Clifford Berry was Atanasoff's graduate student). Shortly after this trip, Mauchly left Ursinus and joined the staff at the Moore School.

By 1942, when LT Goldstine was assigned to the BRL, Gillon became his senior officer. Gillon and Goldstine then set off to grow a significant computing cell at Penn, with Goldstine in charge at the University. As LT Goldstine established the firing tables branch at Penn, it became clear that analogue methods were not to be the long-term solution to ballistic computation. Over the course of months, Dr. Goldstine entered into many technical discussions with John Mauchly. Later, when issues of practical electrical engineering became paramount as well, Presper Eckert established his critical presence as the third member of the core ENIAC team. As the three-way dialogue on the possibilities of digital computing of firing tables went from pure abstraction to possibility, LT Goldstine requested Mauchly to give a formal briefing at the BRL. The brief was presented, and the plan was given immediate approval at Aberdeen. The ENIAC project was under way!

During the past few months, I have had the privilege of first talking with and, Friday, finally meeting with Dr. Goldstine in Philadelphia. Giving generously of his time, he relayed to a number of us many of the technical as well as personal remembrances from this most remarkable period in the history of computing.

An important thread, which Dr. Goldstine emphasized repeatedly, was the bold support, leadership, and friendship given him by his superior officer, COL Gillon.

Just as those of you on this list, Paul Gillon, 88 years of age, received an invitation to the ENIAC celebrations next month in Philadelphia. Today, one of Gillon's son, Brendan, a professor at McGill University in Canada, called me with word that Paul Gillon is gravely ill; however Brendan is planning to join us in Philadelphia on Sunday, February 18th. We've also added Brendan (gillon@langs.lan.mcgill.ca) to this mail list.

We wish the Gillon family our best in this period and look forward to meeting soon the next generation.

FOOTNOTE: On Sunday, 4 February, 1996, I received the following electronic message from Brendan S. Gillon, one of COL Paul Gillon's sons. It read:

Dear Dr. Deitz,

I thought you might want to know that my father, Paul Gillon, passed away at the Charleston Naval Hospital yesterday evening. He died peacefully and in dignity at the age of 88.

He is survived by his wife, Katherine Gillon, his son, Paul Gillon Jr., and his daughter, Teresa Heine, and me, his youngest son.

I was very pleased to be able to report my conversation with you to him. My sister reports that it lifted his spirits considerably.

I look forward to meeting you in Philadelphia.

Brendan S. Gillon

< phd@arl.army.mil >