Computer Science students Louis Hobson and Eddie Cassidy worked on ‘Understanding and Emulating the Turing Bombe’ for their summer research project, supervised by King’s Fellow Dr Tim Flack. The Turing-Welchman Bombe was an electro-mechanical code breaking machine developed by a team of British code breakers during World War II. Kingsman Alan Turing was a part of this team and a key designer of this Bombe which deciphered codes produced by the German Enigma machines. Louis and Eddie were working to create an explanation on the theoretical and mechanical design of the Bombe. They particularly wanted to create an interactive circuit diagram that would completely and fully simulate the operation of the Bombe so that it could actually decrypt messages as well as observe the process which allowed for that decryption.
Louis and Eddie started with collating the fragmented resources on the workings of the Bombe and used these to evaluate what features of the Bombe would be most valuable to focus on in their explanation. In their commitment to accessibility, they put a lot of effort into figuring out their method of explanation to ensure that it was as easy to understand as possible. This meant writing prefaces with the context and theory of the Bombe as an introduction to their diagrams. They created additional interactive diagrams to aid explanations and allow for users to test their own understanding. This all culminated in an excellent website with a simple slideshow-based design and interactive animations to guide a reader step by step in understanding the Bombe.
Louis and Eddie’s main output of the project was their website, which explains how the Turing-Welchman Bombe worked with examples and graphical animations to serve as a public resource. They also managed to create an eight letter (reduced from the full-alphabet 26 letter original for the sake of simplicity for the user) Enigma machine simulator which allows users to encrypt their own messages and a Bombe simulator which allows them to decode them too. This was a great feat and resulted in them winning the Freedman Prize for the Summer Research Programme. The students gained a lot from their experience
The project has been very valuable in a number of ways. It has been hugely intellectually rewarding to take the time to comprehend the workings of such an important part of code-breaking history, and to become part of a relatively small community of people with a deep understanding of the Bombe. The research, design, and implementation of the website was both individually challenging, but also taught us vital communication and collaboration skills that will be useful in any line of work that we pursue in the future. Insight into the world of research will help us make important decisions about industrial compared to more academic career paths.
