26/07/2020

"Cipher with Don Juan de Borgia (1579)" Turned Out to be the One Reconstructed by Devos

The cipher I reconstructed some years ago and call "Cipher with Don Juan de Borgia (1579)" turned out to be the same as the one reconstructed by Deovos (p.414). I reflected this finding in "Spanish Ciphers during the Reign of Philip II".
So many different ciphers were in use in history, and it is hard to find out whether a cipher one is dealing with is already known elsewhere. I myself have noted multiple times that one cipher found in one source is the same as another cipher in another source. When I reconstruct a cipher, I always check whether it is already among the known ciphers (collected on my website), but this one slipped my check.

25/07/2020

Two New Unsolved Ciphers

I added two unsolved ciphers in "Unsolved Historical Ciphers".
One is Juan de Idiaquez Olazabal y Pedro Gonzalez de Mendoza to Philip II (15 March 1557).
The other is Fra Guglielmo Vizani's letter (8 October 1637).

24/07/2020

Ciphers from Louis XIII's time

I uploaded a new article: "French Ciphers during the Reign of Louis XIII".
I pointed out in 2019 that code elements with figures with diacritics used early in the reign of Louis XIV (1661, 1675, 1676) had already been in use during Henry IV's time. Most of the specimens of ciphers from Louis III's time presented in the present article follow this pattern.

22/07/2020

Two More French Ciphers from Henry IV's Time

I added Salignac's Cipher and Lisle's Cipher in "French Ciphers during the Reign of Henry IV of France".
They are similar to other ciphers at the time, but the 1607 specimen of Lisle's cipher uses two-digit figures not used in the 1606 specimens. It is wondered whether the figure symbols were added, or Lisle simply didn't use figures in 1606.

11/07/2020

Cardinal Richelieu's Cipher (1641) Identified

I mentioned a recent solution (by Norbert) of Cardinal Richelieu's cipher letter from 1641 in "Unsolved Historical Ciphers". While Richelieu is said to have used the Cardan grille, this is the first specific cipher used in Richelieu's correspondence known to me. Basically, it is a homophonic substitution cipher that has numbers, letters, and other symbols to represent the letters of the alphabet.