I uploaded a new article, "Brûlart de Léon's Cipher Disk and Treatise on Cipher" at Academia.edu. I got interested in the image of a cipher disk included in BnF fr.17538, and found that the volume also includes a treatise on cipher that describes many cipher schemes.
To me, ciphers with a double meaning are the most interesting. (I found Pascal's reference to "cipher" the other day when searching for "chiffre a double sens".)
Some schemes are similar to Francis Bacon's biliteral cipher. At first, I was thrilled, thinking that I might have discovered a work that anticipated Bacon's idea. But similar ideas (triliteral cipher etc.) had already been described by Porta and Vigenère.
I also uploaded a draft version in Japanese.
I reconstructed a cipher used by Brulart de Leon in 1615-1618 during his embassy in Venice, and included it in "French Ciphers during the Reign of Louis XIII". This cipher does not seem to be particularly different from other ciphers used at the time.
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