Steganography, in modern usage, is the art of concealing a message – not just concealing its content, but disguising that a hidden message exists. Appropriately, although this book appears to offer instructions for magical communication with angels, it conceals a guide to cryptography, that is, writing in code.
Johannes of Trittenheim (1462–1516) was a German monk and historian. He wrote the Steganographia around 1500 and it circulated in handwritten copies for the next century. One transcript belonged to the Elizabethan conjuror John Dee and is now preserved in the National Library of Wales.
This was its first printed publication, long after Trithemius’s death. His Faustian reputation swiftly led to the inclusion of Steganographia in the Catholic Index Librorum Prohibitorum or List of Prohibited Books.
Printed at the end is the Clavis, or Key, which explains the method of encryption in the first two parts of the Steganographia. The third section, however, remained unexplained until 1998, when the tables of numbers were identified as a substitution cipher.
Owen McKnight (Librarian)
Sources and further reading:
- Catalogue record on SOLO
- Jim Reeds, ‘Solved: The Ciphers in Book III of Trithemius’s Steganographia’, Cryptologia 22(4) 291–317 (1998)