J. Presper Eckert

Cocreator of the ENIAC

• Born: April 19, 1919
• Birthplace: Philadelphia, Pennsylvania
• Died: June 3, 1995
• Place of death: Bryn Mawr, Pennsylvania

Primary Company/Organization: University of Pennsylvania

Introduction

J. Presper Eckert with John William Mauchly invented the first general-purpose digital electronic computer, the Electronic Numerical Integrator and Computer, or ENIAC. They also designed the Binary Automatic Computer (BINAC). Their most notable contribution to the early development of modern computing was the Universal Automatic Computer (UNIVAC). Their business acumen was less than their technical inventiveness, and their computer company was bought by Remington Rand, which became Burroughs and eventually Unisys.

Early Life

John Presper Eckert Jr., more familiarly Pres, was born on April 9, 1919, in Philadelphia, Pennsylvania, to John Presper Eckert and Ethel Hallowell Eckert. The family was well off, part of the Philadelphia elite; John, Sr., was a self-made millionaire real estate developer. Pres was an only child and spent much of his youth building radios and other mechanical and electronic gadgets. He traveled with his father frequently, meeting his father's friends and associates. However, he preferred science to celebrities. Pres liked to draw schematic diagrams on loose scraps of paper, even restaurant checks. At age twelve, he won his first science fair by building a remote-controlled boat. Electromagnets under the boat allowed him to steer it, and he developed a way of having the magnet release one boat and take on another.

Eckert was also highly skilled in mathematics, scoring the second highest in the United States on the mathematics section of the College Board examination behind a classmate. He wanted to attend the Massachusetts Institute of Technology (MIT), but his mother did not want him to move so far away. To keep his son close to home, John, Sr., claimed that he could not afford to pay MIT's steep tuition. Upon discovering his father's lie during his freshman year, Eckert became very angry, which may have had a negative effect on his grades at the Wharton School of Business; moreover, business bored Eckert, so he transferred to the University of Pennsylvania's Moore School of Electrical Engineering and earned his undergraduate degree in electrical engineering in 1941 and his master's degree in 1943.

Eckert remained at Moore after graduation, becoming an instructor. He was the top electronic engineer at the school. One of his summer school students was John Mauchly, chair of the physics department at Ursinus College and twelve years his senior. When Mauchly became a professor at Moore, the two, already close friends, began discussing electronics and designing computers, seeking ever more speed. Eckert was twenty-four when he signed the contract to create the ENIAC. He had already spent time on electronics projects at Philo Farnsworth's television research laboratory in Philadelphia, and at Moore he had worked on ways to measure and time radar pulses.

Life's Work

The Moore School's computer was a mechanical combination of wheels, shafts, and gears run by an electrical motor. It could perform only one function at a time and took up to two days to set up. Faster models, electromechanical, used relays instead of gears, but they were still slow. Harvard had a computer that was simply a large-scale adding machine. MIT had a faster one, still mechanical. Eckert and Mauchly had abandoned the idea of moving parts, replacing them with vacuum tubes. The army was interested, invested, and thirty months later the army and Eckert/Mauchly had ENIAC.

The ENIAC debuted on February 14, 1946, and for many represented the first electronic computer. Its first purpose was to compute ballistics tables so artillery crews could compensate for gravity and wind. Before the first demonstration of Eckert's contribution to computing, fifty or so leading mathematicians and scientists dined on lobster bisque and filet mignon while listening to speeches. Then they walked three blocks to the Moore School of Electrical Engineering on the University of Pennsylvania campus. There they saw the first public demonstration of the room-sized ENIAC, which weighed 30 tons and included eighteen thousand vacuum tubes. Mauchly and Eckert showed the select attendees that ENIAC could compute a shell's trajectory before the shell could reach its target—a tangible sign of its superiority over all previous calculators and an indication that computers had finally become useful rather than novelties.

Before ENIAC, a person with a pencil could add two ten-digit numbers in 10 seconds on average. A handheld calculator cut that time to 4 seconds. The Mark I, Harvard's electromechanical computer, took 0.3 second to add two ten-digit numbers. The ENIAC added the two numbers in 0.0002 second—fifty thousand times faster than a human, twenty times faster than a calculator, and fifteen hundred times faster than the Mark I. The ENIAC accepted additional data at any step of the process and could store data for future use. The ENIAC was even faster at specialized scientific calculations. Although some claim that the ENIAC was a four-function machine capable only of adding, subtracting, multiplying, and dividing, in fact it had the capability of performing three-dimensional second-order differential equations. Speed, memory, and versatility allowed scientists and engineers the option of computing rather than creating and testing scale models, as aircraft designers did to determine drag, something they could do in theory but not in practice because of the volume of calculation involved.

Eckert and Mauchly's decision to eliminate moving parts altogether in the ENIAC constituted one of its primary innovations. Mauchly had studied vacuum tubes, writing about his findings in 1942, and he and Eckert determined that tubes would count pulses. The idea was perceived as fanciful by those who had problems with electromechanical computing as a concept and was regarded as unworkable by those who realized that vacuum tubes were highly unreliable.

At the same time, the university had undertaken the project for developing the artillery tables, a task that was projected to last years because of the massive amount of calculations involved, performed by what was then called “computers” (in reference to the men and women who performed the calculations using mechanical calculators or pencil and paper). A single trajectory involved 750 multiplications, and each table had up to 3,000 trajectories, so the project amounted to a four-man-year exercise.

Seeking a faster way, the army commissioned the University of Pennsylvania to build an electronic computer. Mauchly the physicist and Eckert the electrical engineer built the machine. Then six women computers configured the three thousand switches and eighteen thousand vacuum tubes to solve equations they had previously worked out by hand or desktop calculator. There was no computer language, just manual adjustments of switches and wires. The women were integral, but they were classed as computer operators, the same as secretaries, and the hardware workers got the credit while the software workers were ignored in the back of the room.

The vacuum tubes were of ten different types and “off the shelf,” and all the developers asked was that they be supplied in lots of them. Vacuum tubes blew out frequently, every few days. Some circuits were off the shelf but Eckert designed others: registers and integrated circuits. No modern computer still uses an Eckert circuit, but the concept of a subroutine that runs without human input persists (that was Mauchly's idea and eliminated the Mark I requirement to feed the same tape again and again for repeating the same computation). Programming was by wires and switches, with nothing hardwired and no software. Because mice liked to eat wires, Eckert and the ENIAC team caged mice, fed them samples of all the available insulated wires, and chose the one that the mice did not like to eat.

The ENIAC cost nearly $800,000 to build. Eckert and Mauchly's accomplishment—aside from proving wrong those experts who had said it was not feasible as well as those who had said that there would never be enough demand to justify even two of these huge and expensive machines—was putting together thousands of unstable components into a highly stable system. The resulting machine ushered in a new age of computing by demonstrating the practicality of all-electronic digital computing. After the debut of ENIAC, the Soviet Union (a U.S. ally during World War II but its rival during the ensuing Cold War) wanted to order one. Moore declined because the machine was too great a breakthrough to share with America's Cold War enemy. The U.S. Army used the ENIAC for eight years to calculate ballistics tables, do computations for the H-bomb, and help in wind tunnel design before retiring it in 1955.

Eckert and Mauchly were the two most responsible for the design and creation of the ENIAC and later had commercial success with more sophisticated systems such as the Universal Automatic Computer (UNIVAC). The company they created was one of the concerns that merged into Unisys.

Personal Life

On October 28, 1944, Eckert married Hester Caldwell. The couple had two sons, John Presper III and Christopher. Hester committed suicide in 1953. Eckert married Judith A. Rewalt on October 13, 1962, and with her had two more children, Laura and Gregory. After retirement Eckert remained involved in smaller electronics projects and advocated for personal computers. He died in 1995 of leukemia. Surviving him were Judith, his daughter Laura, and his sons John, Gregory, and Chris.

Bibliography

Baranger, Walter R. J. “Presper Eckert, Coinventor of Early Computer, Dies at 76.” New York Times 7 June 1995. Print. An obituary covering Eckert's major achievements.

DeAngelis, Gina, and David J. Bianco. Computers: Processing the Data. Minneapolis: Oliver, 2005. Print. Includes a chapter on Eckert and Mauchly.

Dyson, George. Turing's Cathedral: The Origins of the Digital Universe. New York: Pantheon, 2012. Print. A survey of the experimentation, mathematical insight, and creative endeavors leading to computers, digital television, genetics, and cosmological models based on computer code.

“ENIAC.” Time 47.8 (1946): 92. Academic Search Complete. Web. 1 May 2012. The magazine article that introduced America's first general-purpose digital electronic computer to the public.

Flamm, Kenneth. Creating the Computer: Government, Industry, and High Technology. Washington, DC: Brookings Institution, 1988. Print. An older work but still useful for the development of the ENIAC.

Randall, Alexander V. “The Eckert Tapes: Computer Pioneer Says ENIAC Team Couldn't Afford to Fail—and Didn't.” Computerworld 40.8 (2006): 18. Academic Search Complete. Web. 1 May 2012. Discusses interviews with Eckert, taped in 1989, in which he discusses ENIAC's technology and corrects some myths.

Sobel, Rachel K. “Faulty Memory.” U.S. News and World Report 132.4 (2002): 70. Academic Search Complete. Web. 1 May 2012. Points to the historic omission of credit for the women “computers” who programmed the ENIAC.

Swedin, Eric G. and David L. Ferro. Computers: The Life Story of a Technology. Westport: Greenwood, 2005. Print. A history of computers from ancient beginnings to the time of publication, designed for a general audience.

“Unisys Corporation History.” International Directory of Company Histories, Vol. 36. Detroit: St. James, 2001. Print. Profile that is dated but still useful on the history of Unisys, including mergers and restructurings well past the lifetime of Eckert.