Eckert, J(ohn Adam) Presper, Jr.

(b. 9 April 1919 in Philadelphia, Pennsylvania; d. 3 June 1995 in Bryn Mawr, Pennsylvania), electrical engineer who invented and built the computers that initiated the digital age.

Eckert was the only child of John P. Eckert, Sr., a self-made millionaire builder of parking garages and apartment buildings, and Ethel Hallowell, a homemaker whose grandfather had been a successful inventor and manufacturer of confectionery equipment. As a boy, Eckert traveled extensively with his family throughout the United States, Europe, and the Middle East. He was five when his father brought home one of the earliest radio sets, and he was instantly captivated, building a succession of radios and other electronic sound devices throughout his school years. One of his most ambitious tinkerings was a table-top pond on which boats were manipulated by magnets on tracks underneath the table—when he was twelve the toy won him first prize in a Philadelphia hobby fair. While in high school at the William Penn Charter School, Eckert was able to do odd jobs in the nearby laboratory where Philo Farnsworth was developing electronic television.

After graduating from high school in 1937, Eckert enrolled at the University of Pennsylvania, where he ultimately received both a B.S. degree (1941) and an M.S. degree (1943) in electrical engineering. As an undergraduate, Eckert demonstrated his brilliance during summer consulting jobs more than he did in the classroom, and he learned how to build reliability into fragile instruments. While a first-year graduate student at Penn in 1941, he happened to meet John Mauchly, twelve years his senior, a small-college physics professor with a long interest in the possibility of electronic computing. Mauchly’s interest had been heightened and focused more on digital technology by a recent trip to see a desk-sized device to solve simultaneous equations that John Atanasoff was attempting to build at Iowa State College. Mauchly had been told by experts that vacuum tubes blew out too often for thousands of them to be combined in a single device. Eckert—with a youthful confidence bolstered by years of past engineering successes—assured him that it could be done, and the two began swapping ideas.

After the United States entered World War II, the U.S. Army began building new artillery pieces faster than it could produce the voluminous firing tables needed to aim them under varying conditions. Eckert and Mauchly proposed the development of a general-purpose electronic digital computer to calculate the tables, and in the spring of 1943 the army agreed to back the project at Penn. The twenty-four-year-old Eckert was named chief engineer. With Mauchly as an invaluable consultant, Eckert tirelessly drove a project that eventually involved dozens of engineers and technicians. His style could be brusque, but he was universally respected for his engineering genius.

Eckert and Mauchly’s digital calculating machine, called ENIAC (electronic numerical integrator and computer), was completed in the fall of 1945, only two and a half years after it had been authorized but too late to play any role in the war. Covering as much floor space as a small house, with 18,000 vacuum tubes and endless plug-in cables, ENIAC could compute in thirty seconds a table that would take a person twenty hours.

Meanwhile, early in 1944, once the ENIAC design had been frozen but technicians were still building it, Eckert and Mauchly began to explore the concepts for a second machine, called EDVAC (electronic discrete variable automatic computer), which would incorporate memory and stored programs. As the essential memory device, Eckert proposed a mercury-delay line he had helped invent while working on radar projects early in the war. Later in 1944 the renowned mathematician John von Neumann visited the project and joined in the periodic discussions of the small EDVAC design group. (In 1945, while ENIAC was still shrouded in wartime secrecy, von Neumann drafted a summary of the group’s thinking that was circulated under his name. Ever since, the stored program concept has been popularly, but erroneously, attributed to von Neumann alone.) That same year, Eckert married Hester Caldwell; they had two children.

In February 1946 the army and the University of Pennsylvania publicly demonstrated ENIAC, informing the world of the birth of a new technology of “electronic brains.” Penn also organized a summer lecture program in which Eckert, Mauchly, and others of the ENIAC team transmitted its secrets to two dozen key engineers, several of whom subsequently built important new machines. Indeed, virtually all of the new British and American computer projects of the late 1940s had important links to ENIAC and EDVAC. ENIAC itself performed valuable calculations for the military for a decade.

By then the two inventors had left Penn to found a company soon known as the Eckert-Mauchly Computer Corporation, the first in the world to build electronic digital computers, for which they proposed a wide range of business, governmental, and research applications. Mauchly concentrated on sales, while Eckert began designing UNIVAC (universal automatic computer) as a stored-program computer with mercury-delay lines for internal memory and specially-developed magnetic tape for data storage.

The machine took more time and money than the partners had estimated, and in 1950 they were forced to sell their company to the Remington-Rand Corporation—soon to be Sperry-Rand and ultimately Unisys. There Eckert led the completion of UNIVAC, and the first machine was turned over to the U.S. Census Bureau in March 1951. It was the first general-purpose electronic computer manufactured for the commercial market.

Some twenty UNIVACs were sold over the next three years, demonstrating that computers could play an important role in business as well as science. For its coverage of the 1952 presidential election, the CBS television network had Eckert feed the earliest returns to a UNIVAC, and the machine quickly produced the unexpected, but accurate, results that Dwight D. Eisenhower’s victory would be a landslide. Overnight “UNIVAC” became synonymous with “computer” in the American mind. Sperry-Rand, however, was more attuned to mass-producing typewriters and electric razors than investing millions in developing new technology. By contrast, IBM, jolted by UNIVAC’s threat to its traditional line of mechanical punch-card processors, mobilized its capital and sales force to enter and eventually dominate the field of electronic computing.

At Sperry, Eckert continued to lead the development of several new generations of UNIVAC and other computers. In later years he continued to advise the company on computer development, but his best ideas—in such areas as personal computers and optical character recognition—were too visionary to find favor in a large commercial organization. Trying to get them accepted was, he complained, like “swimming in molasses.”

Eckert’s wife Hester died in 1952; in 1962 he married Judith Rewalt, and they had two children. Eckert was awarded the National Medal of Science in 1969. In 1973 a federal judge invalidated the broad patent that Eckert and Mauchly had obtained on the electronic digital computer and many specifics of the ENIAC design. While acknowledging ENIAC as a “pioneering achievement,” the judge found that the claim had been filed too late and that it owed too much to Atanasoff’s relatively unsophisticated and never-completed machine. Patent issues aside, historians recognize ENIAC as a landmark in computer technology that owed much to Eckert’s inventive genius. Eckert died of leukemia in Bryn Mawr. He is buried at Valley Forge Memorial Gardens in King of Prussia, Pennsylvania.

Eckert was the master engineer of the dawn of the computer revolution. Together with Mauchly he demonstrated to the world the feasibility and applicability of electronic digital computers and founded the computer industry.

There is no full-length biography. Scott McCartney, ENIAC: The Triumphs and Tragedies of the World’s First Computer (1999), does an excellent job of describing the accomplishments of Eckert and Mauchly. An earlier popular overview is in chapters 5–8 of Joel Shurkin, Engines of the Mind: A History of the Computer (1984). A more academic evaluation is Nancy Stern, From ENIAC to UNIVAC: An Appraisal of the Eckert-Mauchly Computers (1981). The only full treatment of Eckert’s early life is Peter Eckstein, “J. Presper Eckert,” IEEE Annals of the History of Computing 18, no. 1 (spring 1996): 25-44, ending with the beginning of his work on ENIAC. Records from the UNIVAC Division of Remington-Rand are at the Hagley Museum and Library in Wilmington, Delaware. An obituary is in the New York Times (7 June 1995). A 1988 oral history is in the Smithsonian Videohistory Program.

Peter Eckstein