Notes: Episode 112, Alan Turing

As with every show, I’ll list any corrections or clarifications here. If there’s anything I’ve overlooked, please contact me by email or in the comments and I’ll edit the notes to reflect the new information.

4:32 – John and Alan were the only two children – I didn’t miss any here.

5:26 – I’m still rather confused as to why “public school” refers to a private institution in Britain while what I grew up calling a public school would be called a “state school”. It seems to have its roots in the fact that they’re open to the public, as long as they can pay, as opposed to other institutions that restricted attendance based on religion, address, and so on. The most famous ones have their roots in charitable organizations that were granted a measure of independence by the state in the 19th century. Honestly though that’s about all the digging I’m willing to do – I’m sort of willing to just write it off as calling trucks “lorries” and car hoods “bonnets” and all that.

18:10 – The Analytical Engine was programmed using punch cards.

20:00 – I’m going to get eaten alive if the wrong people notice this error, but there was really very little shelling at the Battle of Midway (and almost no effective shelling). It was almost entirely fought using aircraft-delivered bombs and torpedoes. However, my point stands that in general the ranges being used at this point in history required a level of sophistication for firing solutions that was unprecedented before the 20th century, and these solutions needed to be calculated without electronic aid.

1:13:41 – I sort of breezed past the “got their hands on machines eventually” part, but several major breakthroughs came with the capture of a number of u-boats – most notably U-570 in August of 1941. This gave Bletchley Park physical Enigma machines as used by the kriegsmarine, allowing them to more directly confirm solutions. Remarkably, though the kriegsmarine knew about this capture, they decided that the crew would have destroyed any sensitive documents making the machines useless.

1:18:02 – I’m not sure I was clear enough about the fact that the main difference between Colossus and earlier bombe methods was that it relied significantly less on cribs. Instead it utilized statistical analysis: the frequency with which certain letters appear in a given language. If a setting returned a solution with an appropriate percentage of E’s, R’s, and so on, it would be flagged as a potential hit.

1:46:53 – The first bombe was named “Victory”.


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