An Original French Naval Code (1778)

An original French code (1778) is reproduced in Pierrot, Chaline, Damoiseau-Malraux, Mekhail, Perret (2025), "A Caribbean Directory-based Encryption during the American War of Independence" (HistoCrypt 2025).
It was for D'Agoût, governor of Saint Domingue (1777-1780). It is a two-part code consisting of a table for encoding in alphabetical order and a separate table for decoding in numerical order. The substitution table assigns three figures for the vowels and one figure to the other letters and the ampersand.
The nomenclature includes entries for syllables and common words. As was typical with French ciphers, some variants are covered by one entry: "action, s" (for "action", "actions"), "it, e" (for "it", "ite"), "puis, que" (for "puis", "puisque").
It should be noted that the codes are made on printed templates. The template for encoding has syllables and words printed in alphabetical order, with a section "NOMS de Lieux" in which place names are not printed and are filled when preparing a code for a specific application. The decoding table has printed numbers 1-850.

Pierrot et al. (2025) reports their reconstruction of a similar code used in 1782 between Guillaume de Bellecombe, governor of Saint Domingue a few years after D'Agoût (1782-1883), and the Secretary of State for the Navy. The number ranges up to 857. There might have been a necessity for additional entries 851-857 beyond the template range 1-850.

Contemporary French diplomatic codes I know had 1200 entries (Barbé-Marbois (1782), Luzerne (1781), Napoleonic age), larger than these naval codes. On the other hand, the code used in one undecoded message between Admiral D'Estaing and Gerard, French minister in Philadelphia, (1779) ("Unsolved Historical Ciphers") has a highest number 597.

Tuple Ciphers (Enciphering a letter with two letters)

I read about reconstruction of an interesting cipher (1537-1547) in a paper by Lasry, Simonetta, and Biermann in HistoCrypt 2025. It enciphers a letter with two letters, while enciphering a syllable with a letter. Moreover, frequent omission of the dot to distinguish syllables makes it look polyphonic. My new short article "Tuple Cipher -- Enciphering a Letter with Multiple Letters" focuses on the aspect of enciphering a letter with multiple symbols.

Dutch Codebreaking Activities during WWI

Florentijn van Kampen (2025), 'Dutch Cryptanalysis of Four American Diplomatic Codes in World War I' (HistoCrypt 2025) is interesting in describing Dutch codebreaking activities during WWI. Beside that, it presents examples of how code (as opposed to a cipher) can be broken. It is also valuable for me to show sources about the US State Department Codes. I updated "How to Break a Code (Not a Cipher)" and "Red and Blue: First Official Codebooks Adapted for Telegraphy" by mentioning these.

Verification of Decryption of Beale Cipher No.2

I have not paid much attention to the famous cryptogram known as the Beal Ciphers (No.1 - No.3). Many consider them a hoax, but at least the Beale Cipher No.2 can be deciphered by using the Declaration of Independence as a key. I recently read that it has been pointed out that deciphering the Beale Cipher No.2 with the given key is not so straightforward. Indeed, there are numerous errors in the numbers. Although the correct reading might have been achieved by close study, it seems unnatural that such painstaking effort is not mentioned in the original pamphlet.
I uploaded a new article ("Errors in Beale Cipher No.2") about this.
(It's a pure coincidence that it's the Independence Day today.)