Geoff Tootill: working with Alan Turing

Geoff Tootill recalls working with Alan Turing at Manchester in the 1940s.

Listen to the full interview track and all other tracks from this interview on British Library Sounds

Oh yes, Alan Turing was working at NPL, and he was becoming frustrated by the fact that their computer project was stalled. So he got a copy of the instructions for the Baby and wrote a program for doing long division and sent it up to us. And I corrected it because it had an error in it, I’ve forgotten what that was, but I was astonished that Alan Turing should write a program containing an error. But then of course he was like that, he was extremely untidy in his – in many of his habits. He spent quite a time in our lab where we had the Baby machine installed. So I got on with him quite well. He realised that I had a maths degree. And he was struggling with a piece of paper one day and I asked him whether I could give him a hand. And he said, ‘Yes would you check this addition?’ And it was an addition table and it was for radix 32. And he’d written it all out by hand, this was quite a monstrous great tabulation on quite a large sheet of paper, and he said, ‘Would you like to check that please?’ So [laughs] I said, ‘Oh really? I don’t know I could do much good trying to check that by hand, I should make just as many mistakes, well probably many more mistakes than you’ve made in writing the thing down.’ So he was quite surprised at this [laughs].

  • Interviewee Geoff Tootill
  • Duration 00:02:10
  • Copyright Geoff Tootill
  • Interviewer Thomas Lean
  • Date of interview 1/15/2010
  • Shelfmark C1379/02

Related Audio Clips

The following clips are short extracts from an in-depth interview.
To listen to the full interview visit

Related themes

Related disciplines