The National Museum of Computing celebrated the upcoming centenary of the birth of Alan Turing with a lecture at Bletchley Park on Thursday night. The event, Turing and his Times, is the second of three Turing-themed events linking three of the top computing museums in the world*.
Turing and his Times featured a talk by computer historian Prof Simon Lavington on Turing and his contemporaries, and a simulation of the Pilot ACE computer by museum trustee Kevin Murrell. Turing worked on the Pilot ACE (Automatic Computing Engine) computer at the National Physical Laboratory (NPL) for around two years after his celebrated work during the war as a codebreaker at Bletchley, working on the German naval Enigma.
Both Lavington and Murrell praised Turing's brilliance in the post-war period leading up to his tragic death in 1954. Turing produced one of the earliest detailed specifications for a universal stored-program computer by the end of 1945, when he was working at NPL. Lavington and Murrell also pointed out that Turing hadn't always interacted easily with his computing colleagues during what had been some fairly stressful times. Turing's relationships with engineers working on the project had been uneasy, and he had been annoyed by delays associated with the project.
By 1948 Turing had resigned from NPL. A year later, innovative computers designed by others had burst into life at the Universities of Cambridge and Manchester, beating NPL to the punch.
The event also featured a 10-minute video commissioned by NPL featuring interviews with Tom Vickers and Mike Woodger recalling their time working with Turing on the ACE computer project.
Codebreaking at Bletchley Park was a team effort that involved mathematicians, linguists and other intellectuals as well as numerous staff involved in the sometimes tedious work of processing messages prior to decryption. Lavington explained that the system allowed for Oxbridge dons to work on fundamental research on crypto-analysis and do solitary work involving deep thinking about complex problems, which is why Turing was a massive success there even though he wasn't a team player.
"Turing went to the US during his work on the naval Enigma, prior to returning to work on speech encryption in the latter part of the war," Lavington explained. "For much of the war he was semi-detached from Bletchley."
Turing was described as a classic English eccentric and some of his peculiarities were discussed during the event. It's fairly well known, for example, that Turing cycled around the Bletchley area in a gas mask as a defence against his hay-fever. What's less well-known is that his bike had a problem with its chain, and that rather than getting it properly fixed, Turing would instead count the revolutions of the chain and get off just before the chain was about to slip off to put it right.
The celebrated codebreaker was nominal head of Hut 8, which worked on the Naval Enigma. In practice, however, he had little interest in the day-to-day running of the section, which was handled by his deputy Hugh Alexander. It is said that Turing wouldn't talk to junior members of staff.
The computer historians at the event also related how one of Turing's "eccentricities" involved chaining his tea mug to the radiator in Hut 8. Years later, when the lake adjacent to Bletchley Park was drained in a search for Enigma machines, workers found several cups and mugs that had been thrown into the lake by Alexander during his morning walks, presumably somewhat absentmindedly when he was in a bad mood. So although odd, there was probably good reason for Turing's worries over mug security.
A display about Turing and the Pilot ACE at TNMOC in Block H at Bletchley Park included a copy of Turing's 78-page Pilot ACE proposal to NPL, the original NPL patent for acoustic delay lines and some examples of the use of the Pilot ACE. ®
* The first event took place at the Computer History Museum in California and featured a talk by George Dyson on Turing's Cathedral. The third event is scheduled for 26 May at the Heinz Nixdorf Museum in Germany, and will feature the museum's working mechanical Turing machine as well as various talks. Follow the three museums Twitter feed here.
During the event we caught up with long-term Reg contact Craig Heath, who has developed an Android simulation of the Enigma. The software, which can work on tablets or smartphones, was accepted by the Barnes & Noble Nook store earlier this week.
The app features realistic animation of the scrambler wheels and other features of using the Enigma machine. The software is advertising supported but users can turn this off in exchange for a payment, half of which is been donated to the Bletchley Park Trust.
Heath said there are several Enigma simulators for iPhones but only two running on Android kit. One is a good quality paid-for application, while the other is free but of poor quality, he said. We tried out the Enigma Simulator on an Android tablet and were impressed by the results.