Jerry McCarthy’s day job used to be to write software, in areas such as retail systems, cryptography and internationalisation, for a global computing company. Since his retirement, he now volunteers at The National Museum of Computing (TNMOC), which is situated within the Bletchley Park Campus. There, he talks to visitors about, inter alia, Tunny, Colossus, and the Museum’s slide rule display. He also volunteers at the Instytut Józefa Piłsudskiego, Hammersmith, where he gives the occasional talk on matters cryptological, such as Enigma and early Polish systems for breaking it.
Zygalski sheets: Polish codebreaking and the role of reconstruction in the Top Secret exhibition at the Science Museum
A reflection on reconstructing Zygalski sheets, a manual grid-based system used by the Polish Cipher Bureau and Bletchley Park to decrypt German Enigma cipher messages, for the Top Secret exhibition at the Science Museum Group from 2019 to 2022.