14/11/2020

Letters Deciphered by John Wallis Sold at Auction for £29,000

It is well-known that a collectioin of fifty-two letters deciphered by John Wallis was deposited at the Bodleian Library, Oxford. Wallis actually made multiple copies of the volume, and on 7 October 2020, one (possibly Wallis's own) was sold at an auction for £29,000. It even includes a fifty-third letter not included in the copy at the Bodleian Library. I added a reference to this in "John Wallis and Cryptanalysis", and also made a few additions from Philip Beeley's paper (2016) referenced by the auction site.
The auction site has some images.
One is Charles I's letter to his son in February 1647, which I already covered in "King Charles I's Ciphers".
Another is a letter from French agent Graymond to Cardinal Mazarin. The cipher used seems to be the same as Graymond's cipher I recently reconstructed from another source and presented in "Ciphers Early in the Reign of Louis XIV".
Another is a letter from the Earl of Lauderdale to the Countess of Carlisle. I now added this in "King Charles II's Ciphers during Exile".
According to the auction site, nearly half of the collection are "from royalist agents in Breda to Dutch and English merchants and other contacts in London: dating from 1650, these relate to the negotiations by which the exiled Charles II was offered passage to Scotland and a means of recovering the throne in England, in return for accepting the authority of the Scottish kirk and parliament." These may include a key between Charles II and the Duke of Hamilton used in some undeciphered letters. I noted this possibility in "Unsolved Historical Ciphers".

11/11/2020

Ciphers of Charles IX and Queen Mother, Catherine de Medici

I added a section "Ciphers of Charles IX and Queen Mother, Catherine de Medici" in "French ciphers during the Reigns of Charles IX and Henry III", now renamed from "French ciphers during the Reign of Henry III of France". (I thought separate treatment of the reigns of these brother kings was not necessary.)
As far as I remember, this is the first time I came across ciphers used in the correspondence of Catherine de Medici. The same ciphers were used in letters to the King and Queen Mother as far as these specimens are concerned.
I have been wondering whether Catherine de Medici brought something new to the French cryptography, but these specimens show no such evidence.

02/11/2020

Earliest Known French Ciphers

The earliest known specimen of French ciphertext is from January 1526 (or possibly September 1525). This is a few months earlier than the earliest mentioned in a scholarly paper (2018). This and other French ciphers during the reign of Francis I are described in the new article "French Ciphers during the Reign of Francis I".
It includes some undeciphered ciphers, which are now mentioned in "Unsolved Historical Ciphers".

01/11/2020

Two Ciphers Broken by George Lasry

Two of unsolved ciphers presented in "Unsolved Historical Ciphers" have been solved by George Lasry.
One is a ciphertext (Senecey to Archbishop of Lyon) left undeciphered by François Viète (see "Ciphers Broken by François Viète").
The other is an Italian letter in the French archives (see "Undeciphered Letters in BnF fr.4715").
Senecey's cipher employs as many as 79 symbols in a relatively short ciphertext, and was very hard to break even with his sophisticated computer algorithms, which appear to have solved the Italian letter in an instant. I look forward to a paper detailing his method.

18/10/2020

Regent Marie de Medici's Cipher

I found undeciphered passages in Marie de Medici's letters (1610) in BnF fr.3789 and included it in "French Ciphers during the Reign of Louis XIII" and "Unsolved Historical Ciphers".
The same source also included Villeroy's letter in cipher. The latter cipher turned out to be the same as one I previously reconstructed from BnF fr.15578 presented in "French Ciphers during the Reign of Henry IV of France".

11/10/2020

Cipher between Emperor Charles V and Juan Perez (1527)

I added an unsolved cipher in a letter from Juan Perez, ambassador in Rome, to Charles V and another from Charles V to an unnamed recipient in "Ciphers during the Reign of Emperor Charles V" and added references to these in "Unsolved Historical Ciphers".

10/10/2020