The cipher of Emperor Rudolf II’s “Alchemical Hand Bell”


We examine a cipher found inscribed in the so-called “Alchemical Hand Bell” from the Kunstkammer of Emperor Rudolf II. We provide insight into the bell’s history, a correction for an existing published transcription, perform statistical analysis of the ciphertext, and look at possible encryption methods and plaintext languages. Given the analysis, we examine the possibilities of digraphic and polyphonic ciphers and give a brief overview of how these were used in the historical context.

Proceedings of the 6th International Conference on Historical Cryptology HistoCrypt 2023