Pi History - D. F. Ferguson, the Destop Calculator, & Pi
The Illustrated History of Pi
D.F. Ferguson, the Desktop Calculator, and Pi
  The desktop calculator, although a relatively primitive instrument by today's standards, was a technology tour-de-force in its day.
  In 1947, D. F. Ferguson, working with a destop calcuator, was able to calculate 808 digits of pi.
  This was subsequently extended by others using new technology ... the electronic digial computer ...
History of Pi - D F Ferguson, The Desktop Calculator, and Pi - Illustrated History of Pi www.NationalPiDay.org National Pi Day