For a while, I’ve been wondering about what “the new Kahn” (i.e. what the updated, 2007 equivalent of David Kahn’s “The Codebreakers“) would be. On a whim, I recently bought a couple of plausible-looking cryptography history books, just in case one of them might be that book…
“Codes, Ciphers, Secrets and Cryptic Communication” by Fred B. Wrixon is quite cool. In its 704 pages of cryptographic and cryptologic fun, it bounces along at a fair old rate, not only discussing plenty of different historical ciphers but also describing ways of cracking them – both making and breaking. It has two brief pages on the VMs (pp.555-556). Its weakness (in my opinion) is that it is somewhat fragmented (in an encyclopaedic kind of way), possibly because it was formed by merging two earlier books by the same author into a single larger book. Good if you want a quicky book to tell you how to break historical ciphers. But not Kahn.
“Codebreaker: The history of secret communication” by Stephen Pincock and Mark Frary is OK, but didn’t really work for me. Consistently misspelling Trithemius as Trimethius (even in the index) didn’t help in this regard: but the book has other merits, such as the glorious colour photograph of the Phaistos disk on page 5. It’s a well-illustrated piece of popular science journalism, with three colourful pages on the VMs (pp.49-51, showing f11r, f56r, and f67r1-2, though labelling them “Nature and alchemy” might be a little be off the mark). Random House obviously thought there was a need (in these post-Da Vinci Code days) for a colourful cryptography / history / journalism thing: I’m not so sure. I suspect the authors would have been better off telling a historical story than what they produced: beautifully produced, but not really enough of any substance, nor large enough to be a proper coffee table book. (Sorry!)
Which leads me back to David Kahn. If you are serious about reading up on the history of cryptography, I’d suggest searching on BookFinder.com for a copy of the unabridged (1136 page!) version of “The Codebreakers”. For now, Kahn is still king! 😮
Nick: I was wondering about emailing David Kahn to provide a correction on his remarks in his book on 15th century ciphers where it seems to be very wide of the mark. I don’t know if he is likely to bring out a new version of his book. Do you have his email address?
What he says about late 14th century ciphers seems to accord with my understand though I have some questions for him.
Nick: Don’t get me wrong, I don’t doubt Kahn has done an excellent job writing on the history of cryptography. My research has just concerned a tiny sliver of history, though that narrow focus has allowed me to look at that sliver in great depth.
Kahn in his book says “The West’s earliest known homophonic substitution cipher, used at Mantua with Simeone de Crema in 1401”
Now it has already been established that there a homophonic substitution cipher dated to 1397 in Sercambi’s book.
Even if one isn’t aware of Sercambi’s book this is still not quite right. In the Gonzaga ledger there are many cipher keys, some with homophones and some without homophones. Some cipher keys have a year written next to them and some have no year written next to them. The Simeone de Crema cipher key has homophones and is the one with the earliest year beside it. However there may be cipher keys in the ledger with homophones that are earlier than it, but which lack a year written next to them to attest their age.
Now Kahn can be forgiven for this slightly inaccurate statement due to the requirements of brevity.
However this raises a question about dating cipher keys in the ledger that do not currently have a date. This is a difficult and probably in some cases an impossible task.
I have recently dated an undated cipher key in the Guinigi ledger to 1407 and established without a doubt that in is Venetian in origin and so it predates what I understand is the oldest stated Venetian cipher, namely from the letter of Michele Steno, by 4 years. Similarly I have done something similar for the Napoleone Orsini cipher key in the Codex Urbinate.
The dating of the Guinigi Venetian cipher can be done through reading about Marino Caravello and Zaccaria Trevisan, whose names head the title of the cipher key.
Maybe this approach can be applied to the tracing of the origins and the dating of other cipher keys.