Turing in Dayton

I’ve been impressed and gratified by the number of visitors to my site who have requested background information after seeing the movie The Imitation Game. I am not a professional historian but I do have a more than passing interest in this topic as my father was one of the key players in Turing’s visits. I’ve assembled a bit of information which may lead people in the right directions.

A aside before I begin: I appreciated The Imitation Game. It was not a documentary like the one Aileen and I produced; more it reminded me of Shakespeare’s historical plays: big theme based on a character study relying on “bending” a few historical inaccuracies for effect (e.g. one would not rely on Henry IV Part 2 to gain documented knowledge about the War of the Roses).

The British code breakers began their work years before the US Navy entered Enigma research in earnest. The two projects overlapped but did not coincide so I can understand why the movie’s producers did not mention the American story.

The Imitation Game only alludes to the dates where each scene might have occurred. Turing began work at the British Government Code and Cipher School in 1938. His major achievements in code breaking occurred in the years 1939, 40 and 41. The Americans did meet with the British several times after we entered the war in December 1941, both in England and in the States if the movie producers but that additional content would only have been distracting.

Turing did visit Dayton in December 1942, argued with my father and wrote a dismal report on the Dayton work. [Read a transcript of the report at Frode Weirud’s excellent collection of research.] But most interestingly Bob Mumma of the NCR team spoke of Turing, his visit and his own impressions in an interview conducted by the IEEE during the 1995 Reunion:

Nebeker:

Yes, that’s interesting. I hadn’t heard about that. What about contact with…you were seeing Navy people all the time here in Dayton. Did you meet any people from England?

Mumma:

Yes, this–oh, I mentioned his name a bit ago, this mathematician–Alan Turing, yes, he was over with us. He came in and told us what we wanted to do and how to do it. I worked with him on that.

Nebeker:

Do you recall when that was?

Mumma:

Oh it was very early in the project. Very early. While we were designing the machines. Before production.

Nebeker:

I see. He in person talked with you.

Mumma:

Oh yes. He was over here. He said, “You’ve got to do this, you’ve got to do this.” He controlled the design more than anyone else did.

Nebeker:

How long was he in Dayton, do you remember?

Mumma:

Oh, months I guess, I don’t know.

Nebeker:

Is that right? What was your recollection of him?

Mumma:

Well, he was a nice fellow. I don’t know. I enjoyed talking to him.

Nebeker:

He seemed approachable?

Mumma:

Oh yes. He knew what he wanted and we weren’t in a position to argue with him. We just said we can do this, we can’t do it, you know. See, he’d done something similar with IBM equipment over there in England. But when the Germans went to the fourth wheel in the Enigma, he couldn’t get it done quickly enough.

Nebeker:

Did he return a second time?

Mumma:

I think he came back. I forget. I think he came back to visit.

Nebeker:

Did you have other visitors from England, do you recall?

Mumma:

No I don’t. We had quite a few Navy people come down, Captain Wenger and some others.

For the entire interview, see Oral History:Robert Mumma at the IEEE Global History Network.

The American bombes went into full production in September 1943.

For further information please see:

The Turing web site originating with and maintained by Andrew Hodges, author of the book Alan Turing: The Enigma upon which The Imitation Game was based. This site is the motherlode of information short of reading Hodges’ groundbreaking book.

Frode Weirud’s compilation of documents about the US Bombe Project