This practical question was one more up Don Bayley's street.
As the European war ground to its end, and the problems of the Delilah were essentially solved, it became clear that Alan's interest had turned to 'the brain'.
He described to his assistant the universal machine of Computable Numbers, and its 'tape' on which instructions would be stored.
They began thinking together about ways in which to realise a 'tape' that could store such information.
And thus it was that in this remote station of the new Sigint empire, working with one assistant in a small hut, and thinking in his spare time, an English homosexual atheist mathematician had conceived of the computer.
That was not how the world was to see it, and the world was not being entirely unfair.
Alan Turing's invention had to take its place in an historical context, in which he was neither the first to think about constructing universal machines, nor the only one to arrive in 1945 at an electronic version of the universal machine of Computable Numbers.
There were, of course, all manner of thought-saving machines in existence, going back to the invention of the abacus.
Broadly these could be classed into two categories, 'analogue' and 'digital'.
The two machines on which Alan worked just before the war were examples of each kind.