Archived posting to the Leica Users Group, 2013/03/10
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]This is probably the last in my series of articles about things in the Computer History Museum. During World War II, the army was in a stew about the slow production of ballistics tables for new artillery weapons. The tables were hand calculated by women who had math degrees. John Mauchly and Presper Eckert at the Moore School of Engineering of the University of Pennsylvania invented a computer named ENIAC for producing these tables. It was a fully programmable computer, could calculate anything. Eckert and Mauchly patented it--this in itself is surprising, since it was supported by government money. Eckert and Mauchly went on after the war to found the corporation which sold a computer called UNIVAC. Ultimately, other companies went into the computer business and a lawsuit occurred in 1967 between the UNIVAC company and Honeywell, which refused to pay UNIVAC a license fee. A U.S. District Court decided that the UNIVAC patent was invalid because of never-patented but publicly disclosed prior art: a computer built by Iowa State College physics professor John Vincent Atanasoff and graduate student John Berry. It was built in the period 1939-1942. For short, it became known as the "ABC Computer". UNIVAC never appealed the decision. Now here is what the ABC computer was designed to do. It would solve up to 29 simultaneous linear equations in 29 variables. It would be fed two equations and would eliminate one variable. This process would be (manually) repeated using one of these shortened equations to shorten the next equation. By repeating this process over and over again, the equations would ultimately be solved. Sounds a pain, but far better than trying to solve them by hand. That is all that the machine could do; nothing else. Furthermore, if one wants to nit pick, the ABC Computer converted the numbers to binary and worked with binary arithmetic, whereas the ENIAC worked directly in decimal. I suspect that courts are more sophisticated today and would have made a different decision. The original computer was too wide to be moved out of a standard door, and ultimately various others at Iowa State liberated its parts. Eventually, it got rebuilt with a slightly smaller case, and is now on loan to the Computer History Museum. http://gallery.leica-users.org/v/herbk1/L1002926.jpg.html Herbert Kanner kanner at acm.org 650-326-8204 Question authority and the authorities will question you.