## John Todd

Link: http://invention.smithsonian.org/downloads/fa_cohc_tr_todd710224.pdf

John Todd begins with a brief review of the growth in his interest in mathematics. His original interest in science and engineering in secondary school in Ireland led to the need for more mathematics. By the time he went to Cambridge as a graduate student he was studying abstract analysis. After which he joined King's College in London as a member of the faculty. It was during the war that he developed his interests in numerical analysis and computing. He served in the Admiralty Computing Service, where he met John von Neumann who at the time was studying underwater ballistics. He recounts the development of computing in England during the war, discussing the activities at the National Physical Laboratory and the Cambridge Mathematical Laboratory, the use of the EDSAC, and Alan Turing and the development of the ACE machine.

After the war, he received an invitation from the U. S. National Bureau of Standards' John Curtiss to come to the Institute for Numerical Analysis in Los Angeles. He spent the first three months of 1948 in Princeton at the invitation of John von Neumann, and then came to Washington DC. He remarks that at the time, the Bureau staff was coding for imaginary machines and had the IBM CPC as their only equipment. He returned to England after a year and then in1949 returned first to Washington and then to Los Angeles. He became the Head of the Computation Laboratory at the Bureau and he left the Bureau in 1957 for the California Institute of Technology.

He discusses the funding of computing in the post war era in England and the United States, the role of the National Bureau of Standards in training University staff in numerical analysis and computer operations, and the development of numerical analysis and computing at the California Institute of Technology.

**Key words**: acoustic, underwater ballistics, EDSAC, ACE, IBM CPC, SWAC, SEAC, Monte Carlo methods, linear programming, force deployment

**Funding agency**: National Bureau of Standards, U.S. Air Force, Atomic Energy Commission, Office of Naval Research, National Science Foundation

**Time frame**: 1940's, 1950's, 1960's, and 1970's

**People**: John von Neumann, Maurice Wilkes, Douglas Hartree, Alan Turing, George Dantzig, Edward Condon, Philip Davis,

**Locations**: Admiralty Computing Service, National Physical Laboratory, Cambridge Mathematical Laboratory, Institute for Advanced Study, National Bureau of Standards Computation Laboratory, Institute for Numerical Analysis, UCLA, California Institute of Technology

**Copyright**: Computer Oral History Center, Lemelson Center for the Study of Invention and Innovation,
Smithsonian National Museum of American History