Magnetic core memory (3, 49-53)

A tutorial by Frederick Doherty, U. of Glasgow

194x, Invented by Jay Forrester & Bill Papian at MIT

1952, Photo and dimensions from IBM 405

1953, installed on both ENIAC and Whirlwind

IBM subcontracted manufacture of cores (3, p53)
Colton Manufacturing, a pharmaceutical company
General Mills, using modified machines for packaging food

1954, IBM is producing 95% yields on its own

1955, IBM delivers prototype for SAGE

1. William Aspray, ed., Computing Before Computers (Ames, IA: Iowa State University Press, 1990 ). Also available online at http://www.computerhistory.org/collections/DocumentArchive/Documents/Books/Computing Before Computers/CBC.html (Computer History Museum, accessed 2004 Aug 11).

2. Martin Campbell-Kelly and William Aspray. Computer: A History of the Information Machine (Basic Books, 1996).

3. Paul E. Ceruzzi. A History of Modern Computing (MIT Press, 2000).

4. Paul E. Ceruzzi, Reckoners, the Prehistory of the Digital Computer, from Relays to the Stored Program Concept, 1935-1945 (Westport, CT: Greenwood Press, 1983). Also available online at http://www.computerhistory.org/collections/DocumentArchive/Documents/Books/Reckoners/Reckoners.html (Computer History Museum, accessed 2003 Sep 27).