Alchemical ciphers | Sarah A. Lang

After my involvement in the decryption of an alchemical cipher (Bean et al., 2021), I have developed expertise in alchemical ciphers and the broader historical and epistemic context of what might be called “occult cryptography.” Because practitioners of some so-called “occult sciences”, including alchemy and astrology, sometimes employed highly sophisticated cryptographic techniques, I contend that this tradition developed independently from diplomatic cryptography, pursuing distinct goals and following its own historical trajectory.

In 2021, my collaborators and I decrypted a rare and highly sophisticated early modern alchemical cipher (Bean et al., 2022)—one of the most advanced techniques of its time, and a rare and early instance of the famous Vigenère type found “in the wild” rather than in cipher handbooks (Lang & Piorko, 2021).

A separate contextual study appeared in Ambix (Piorko et al., 2023), focusing on the cipher’s material form, its association with the figures of John and Arthur Dee, and its place within alchemical cultures of secrecy (Lang, 2023).

Our story was picked up by the media and adapted into a play by French playwright Benoit Solès, Le secret des secrets (Paris 2025).

In the meantime, I have further explored the intersections of alchemy and cryptography more broadly (Lang et al., 2024), including investigations into Rudolf II’s alchemical handbell (Bean et al., 2023), although this has not yet led to conclusive results (Bean et al., 2023).

References

2024

Sources of Alchemical Cryptography

Sarah Lang, Sergei Zotov, and Megan Piorko

In Proceedings of the 7th International Conference on Historical Cryptology (HistoCrypt 2024), 2024

DOI

2023

Deciphering the Hermeticae Philosophiae Medulla: Textual Cultures of Alchemical Secrecy

Megan Piorko, Sarah Lang, and Richard Bean

Ambix, 2023

Abs DOI Bib PDF

This article presents the decryption, historical analysis, and alchemical interpretation of an alchemical cipher found in a shared notebook of John and Arthur Dee (British Library MS Sloane 1902). The cipher is an early example of a Bellaso/Della Porta/Vigenère type, a strong encryption method which was historically deemed indecipherable. The essay explores the medical and alchemical context for the manuscript into which the cipher was copied and provides the transcription, plaintext solution (in Latin), and English translation of the encrypted text. Further, it interprets the enciphered text through the lens of alchemical practice and provides evidence for the dissemination of this cipher as part of a larger alchemical knowledge network.
@article{Lang2023Deciphering, author = {Piorko, Megan and Lang, Sarah and Bean, Richard}, title = {Deciphering the Hermeticae Philosophiae Medulla: Textual Cultures of Alchemical Secrecy}, journal = {Ambix}, year = {2023}, volume = {70}, number = {2}, pages = {150--183}, doi = {https://doi.org/10.1080/00026980.2023.2201744}, url = {https://doi.org/10.1080/00026980.2023.2201744}, keywords = {alchemy, cipher}, }
Situating ciphers among alchemical techniques of secrecy

Sarah Lang

In Proceedings of the 6th International Conference on Historical Cryptology HistoCrypt 2023, 2023
Seven metals, ringed with four magical inscriptions: what other secrets does the ‘Alchemical Hand Bell’ hold?

Richard Bean, Corinna Gannon, and Sarah Lang

Jun 2023
The cipher of Emperor Rudolf II’s “Alchemical Hand Bell”

Richard Bean, Corinna Gannon, and Sarah Lang

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

2022

Solving an alchemical cipher in a shared notebook of John and Arthur Dee

Richard Bean, Sarah Lang, and Megan Piorko

In Proceedings of the 5th International Conference on Historical Cryptology (HistoCrypt 2022), 2022

2021

Deciphering the Philosophers’ Stone: how we cracked a 400-year-old alchemical cipher

Richard Bean, Megan Piorko, and Sarah Lang

Oct 2021
An alchemical cipher in a shared notebook of John and Arthur Dee [Work In Progress]

Sarah Lang and Megan Piorko

In Proceedings of the 4th International Conference on Historical Cryptology (HistoCrypt 2021), 2021