For a full discussion of this item, please refer to the Accession Folder and the paper: van der Spiegel, J., Tau, J., Tittim'a, F., Lin, P.A., " The ENIAC: History, Operation, and Reconstruction in VLSI." Len Shustek writes: Like many computer developments in the 40's and 50's, ENIAC was invented to solve a military problem. The Ballistics Research Lab (BRL) in Maryland was responsible for generating "firing tables" for artillery shells ? based on many complicated factors such as the weight of shells, propellant charge, air resistance (temperature, humidity, projectile shape), etc. The firing table booklets given to the gunners had data for 3000 trajectories, each of which took several days with a desk calculator, and even the mechanical analog computers took 20 minutes, or about 2 months for a complete a table. Lt. Herman Goldstine discovered the work of Prof. John Mauchly at the University of PA Moore School, and in June 1943 commissioned the development of an Electronic Numerical Integrator and Computer (ENIAC) to make the tables more quickly. The chief engineer was J. Presper Eckert; he and Mauchly later formed their own computer company which created UNIVAC and was bought by Remington-Rand. ENIAC was completed in November 1945, so it missed the war by several months, but it was a roaring success. Big: 18,000 vacuum tubes (reliable if on all the time: one failure every 2 days), 100' long by 8' high, 30 tons. (We have one of about 40 panels.) Expensive: It was supposed to cost $150K, but really cost $500K. Fast: 5000 additions per second, 357 multiplications per second, or one trajectory calcuation in less than a minute. (Less time than it takes the shell to travel! Less than two days for a whole ballistics table). After the war they used it for other pusposes (atomic bomb calcuations, cosmic ray studies, wind tunnel design, weather prediction). But it was "programmed" by hundreds of patch-panel wires (for control) and rotary swtiches (for preset data tables). It took days to change the program! The idea of storing the program in memory just like the numbers, which is the essence of the modern computer, was inspired by the difficulty of programming ENIAC. (It was the first "electronic general-purposed automatic computer", but not the first "stored-program" computer, which happened in Manchester England in June 1948.). In its early years ENIAC was the only large-scale electronic digital computer in daily use. It was turned off in October 1955. It has been speculated that, in its 11 years of life, it did more arithmetic than had been done by the whole human race prior to 1945.
Pennsylvania, University of
5/16 x 1 15/16 x 1 15/16 (HWD) in.
Gift of the University of Pennsylvania