Photograph of ENIAC (Electronic Numerical Integrator And Computer), ca. 1945, showing Pres Eckert (centre left) and John Mauchly (centre right) working with the machine, as well as (left to right) Pfc. Homer Spence, Betty Jean Jennings, Herman H. Goldstine and Ruth Lichterman.

[Pennsylvania: n.p., ca. 1945].

Rare photograph, much reproduced in the computer literature, of “the world’s first large-scale general-purpose electronic digital computer” (OOC, p. 532). ENIAC was “built during World War II by the United States. American physicist John Mauchly, American engineer J. Presper Eckert, Jr., and their colleagues at the Moore School of Electrical Engineering at the University of Pennsylvania led a government-funded project to build an all-electronic computer. Under contract to the army and under the direction of Herman Goldstine, work began in early 1943 on ENIAC. The next year, mathematician John von Neumann began frequent consultations with the group … [ENIAC] used plugboards for communicating instructions to the machine; this had the advantage that, once the instructions were thus ‘programmed,’ the machine ran at electronic speed. Instructions read from a card reader or other slow mechanical device would not have been able to keep up with the all-electronic ENIAC. The disadvantage was that it took days to rewire the machine for each new problem … Nevertheless, ENIAC was the most powerful calculating device built to date. It was the first programmable general-purpose electronic digital computer. Like Charles Babbage’s Analytical Engine (from the 19th century) and the British World War II computer Colossus, it had conditional branching—that is, it could execute different instructions or alter the order of execution of instructions based on the value of some data. (For instance, IF X>5 THEN GO TO LINE 23.) This gave ENIAC a lot of flexibility and meant that, while it was built for a specific purpose, it could be used for a wider range of problems. ENIAC was enormous. It occupied the 50-by-30-foot (15-by-9-metre) basement of the Moore School, where its 40 panels were arranged, U-shaped, along three walls. Each panel was about 2 feet wide by 2 feet deep by 8 feet high (0.6 metre by 0.6 metre by 2.4 metres). With more than 17,000 vacuum tubes, 70,000 resistors, 10,000 capacitors, 6,000 switches, and 1,500 relays, it was easily the most complex electronic system theretofore built. ENIAC ran continuously (in part to extend tube life), generating 174 kilowatts of heat and thus requiring its own air conditioning system. It could execute up to 5,000 additions per second, several orders of magnitude faster than its electromechanical predecessors. It and subsequent computers employing vacuum tubes are known as first-generation computers. (With 1,500 mechanical relays, ENIAC was still transitional to later, fully electronic computers.) Completed by February 1946, ENIAC had cost the government $400,000, and the war it was designed to help win was over. Its first task was doing calculations for the construction of a hydrogen bomb. A portion of the machine is on exhibit at the Smithsonian Institution in Washington, D.C.” (Britannica). No other copy in auction records.

“With the country at war, there was a dramatic increase in the amount of ordnance produced for the army and a parallel increase in the army’s need for accurate firing tables. These were complex mathematical tables compiled by the United States Army’s ballistics laboratory at the Aberdeen proving ground in Maryland and used by gunners to aim artillery at unseen or moving targets. Each table took over a month to complete using the resources available at the time – the Bush differential analyzer and teams of human ‘computers’ (mostly women – see below) using mechanical desktop calculators. The Ballistics Laboratory had a long-standing association with the Moore School, which by end of the 1930s was one of the Laboratory’s major suppliers of technical and computational aid; however, even with the aid of the Moore School’s computational equipment the Ballistics Laboratory was falling further and further behind in its firing-table production. This rendered the army’s new weapons essentially useless as without firing-tables it was impossible to aim any artillery accurately” (OOC, p. 532).

“From that need emerged a machine called the ENIAC (Electronic Numerical Integrator and Computer), unveiled to the public in 1946 at the University of Pennsylvania’s Moore School of Electrical Engineering in Philadelphia. With its 18,000 vacuum tubes, the ENIAC was touted as being able to calculate the trajectory of a shell fired from a cannon faster than the shell itself traveled. That was a well-chosen example, as such calculations were the reason the army spent over a half-million dollars for the risky and unproven technique of calculating with unreliable vacuum tubes. The ENIAC used tubes for both storage and calculation, and thus could solve complex mathematical problems at electronic speeds.

“The ENIAC was designed by John Mauchly and J. Presper Eckert at the Moore School. It represented a staggering increase in ambition and complexity over most of the ambitious computing machines already in use. It did not arise de novo. In the initial proposal to the army, Mauchly described it as an electronic version of the Bush differential analyzer, careful to stress its continuity with existing technology rather than the clean break it made. And Mauchly had visited J. V. Atanasoff in Iowa for several days in June 1941, where he most likely realized that computing with vacuum tubes at high speeds was feasible. The ENIAC’s design was nothing like either the Babbage or the Atanasoff machines. It used the decimal system of arithmetic, with banks of vacuum tubes that replicated the decimal wheels of an IBM tabulator. The banks of tubes were used for both calculation and storage—no separation of the two as Babbage, Zuse, and others had proposed and as is common today. The flow of numbers through the machine was patterned after the flow through the analog differential analyzer.

“Of the many attributes that set the ENIAC apart, the greatest was its ability to be programmed to solve different problems. Programming was difficult and tedious. Today we click a mouse or touch an icon to call up a new program—a consequence of the stored program principle. Eckert and Mauchly designed the ENIAC to be programmable by plugging the various computing elements of it in different configurations, effectively rewiring the machine for each new problem. It was the only way to program a high-speed device until high-speed memory devices were invented. There was no point in having a device that could calculate at electronic speeds if the instructions were fed to it at mechanical speeds. Reprogramming the ENIAC to do a different job might require days, even if, once re- wired, it could calculate an answer in minutes. For that reason, historians are reluctant to call the ENIAC a true ‘computer,’ a term they reserve for machines that can be flexibly reprogrammed to solve a variety of problems. But remember that the ‘C’ in the acronym stood for ‘computer,’ a term that Eckert and Mauchly deliberately chose to evoke the rooms in which women computers operated calculating machines. The ENIAC team also gave us the term to program referring to a computer. Today’s computers do all sorts of things besides solve mathematical equations, but it was that function for which the computer was invented and from which the machine got its name.

“If the ENIAC, a remarkable machine, were a one-time development for the U.S. Army, it would hardly be remembered. But it is remembered for at least two reasons. First, in addressing the shortcomings of the ENIAC, its designers conceived of the stored program principle, which has been central to the design of all digital computers ever since. This principle, combined with the invention of high-speed memory devices, provided a practical alternative to the ENIAC’s cumbersome programming. By storing a program and data in a common high-speed memory, not only could programs be executed at electronic speeds; the programs could also be operated on as if they were data the ancestor of today’s high-level languages compiled inside modern computers. A report that John von Neumann wrote in 1945, after he learned of the ENIAC then under construction, proved to be influential and led to several projects in the United States and Europe. Some accounts called these computers ‘von Neumann machines,’ a misnomer since his report did not fully credit others who contributed to the concept. The definition of computer thus changed, and to an extent it remains the one used today, with the criterion of programmability now extended to encompass the internal storage of that program in high-speed memory …

“The second reason for placing the ENIAC at such a high place in history is that its creators, J. Presper Eckert and John Mauchly, almost alone in the early years sought to build and sell a more elegant follow-on to the ENIAC for commercial applications. The ENIAC was conceived, built, and used for scientific and military applications. The UNIVAC, the commercial computer, was conceived and marked as a general-purpose computer suitable for any application that one could program it for. Hence the name: an acronym for ‘universal automatic computer’” (Ceruzzi, pp. 44-51).

During the time period 1942-1955, women were seldom involved in the design of hardware. However, both men and women were employed as computers … The job of computer was critical to the war effort, and women were regarded as capable of doing the work more rapidly and accurately than men. By 1943, and for the balance of World War II, essentially all computers were women as were their direct supervisors. Six of these women computers became the original group of ENIAC programmers. Goldstine identifies these women as the Misses Kathleen McNulty, Frances Bilas, Betty Jean Jennings (incorrectly identified by Goldstine as Elizabeth Jennings), Elizabeth Snyder, Ruth Lichterman, and Marlyn Wescoff (incorrectly listed by Goldstine as Marilyn Wescoff)” (Fritz). Betty Jean Jennings and Ruth Lichterman are shown in the offered photograph.

OOC 1108(3). Ceruzzi, Computing. A Concise History, 2012. Fritz, ‘The women of ENIAC,’ IEEE Annals of the History of Computing 18 (1996) pp. 13–28.

Black and white photograph (228 x 181 mm), two press cuttings dated February 15, 1946 and December 8, 1994 tipped onto verso.

Item #5514

Price: $1,500.00

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