George Lasry’s decipherment
George Lasry’s report on this item, as he sent it on 24 October 2026 (PDF), in its own order and wording. The decipherment, the translation and the reconstruction of the key are his, made with ChatGPT Astra 6 and Anthropic Opus 5.5. This project’s own checks follow under Verification.
Français 3575 — f56r
Contents: The proposed surrender of the château of Clermont to the comte de Montgomery, the danger of alienating the religious party, and a recommendation for a judicial appointment.
Transcribed; Deciphered
- Ciphertext-only:
- Yes
- Sender:
- Unidentified
- Recipient:
- Unidentified
- Year:
- Undated
- Key:
- 43 codes, 43 letter codes
- Ciphertext:
- 782 elements, 774 identified (99.0%)
Excerpt and Translation
f56r, L07–L09 — 56r
Excerpt
…pas dans sa lettre et pretend ne povvoir obeir. Vovs scaves de qvelle importance est Clermont et ez [m]ains de qvi il entrera. C’est à vovs, Monsi…
Translation
…not in his letter, and claims that he cannot obey. You know how important Clermont is and into whose [hands] it will fall. It is for you, Sir…
f56r, cipher lines L09–L13
Excerpt
ez [m]ains de qvi il entrera. C’est à vovs, Monsievr, à y povrveoir, ce qve vovs povvez faire librement car vovs estes av dessvs de l’envye, et ne me mettre en bvtte parce qve cela me rvineroi[t] envers cevx de la religion. Il i a avssy vn afa…
Translation
into whose [hands] it will fall. It is for you, sir, to attend to this, which you can do freely since you are above envy; and not expose me to attack, because this would [ruin] me in the eyes of those of the religion. There is also a matt…
f56r, L19–L22 — 56r
Excerpt
[b]on essient. C’est à vovs à adviser sy vovs lvy vovlez procvrer ce bien car ie tiens qv’il en est digne et ce cera chose profitable av service dv roy, à vovs et à moy.
Translation
in [good] earnest. It is for you to decide whether you wish to obtain this favour for him, because I consider him worthy of it, and it would benefit the king’s service, you and me.
Readable text
The full text, folio by folio, as in the report. Bold marks the passages deciphered from the cipher; the rest is the clear text of the letter. Question marks are the report’s: [?] or a bare ? for a sign or group left unread, a ? after a word for a doubtful reading.
Français 3575
f56r
Ie viens d'estre adverti par le cappitaine Mondon qv'il a eveommandement de vovs de rendre le chasteav de Clermont ez mains dv comte de Montgomery. Ie n'ay point vev la lettre, vovs ne m'en avez rien escript. Leedict cappitaine Mondon dit avoir vn signal avec vovs qvi n'es[t] pas dans sa lettre et pretend ne povvoir obeir. Vovs scaves de qvelle importance est Clermont et ez [m]ains de qvi il entrera. C'est à vovs, Monsievr, à y povrveoir, ce qve vovs povvez faire librement car vovs estes av dessvs de l'envye, et ne me mettre en bvtte parce qve cela me rvineroi[t] envers cevx de la religion.
Il i a avssy vn afaire qvy vovs tovche et à moy, qvy est l'es[l]ection d'vn premier president. Ie vovs avois escrip[t] povr Mr de Vic qv[i] me proteste n'estre chose qv'il desire. Il vovs y favlt vn servi[t]evr obligé. Mr de St Felix est le vostre à [b]on essient. C'est à vovs à adviser sy vovs lvy vovlez procvrer ce bien car ie tiens qv'il en est digne et ce cera chose profitable av service dv roy, à vovs et à moy.
At a glanceCiphertext-only break · complete
- The letter
- Unidentified sender and recipient, undated; it mentions Clermont and Montgomery (Wars of Religion, perhaps the 1560s–70s).
- Where
- Bibliothèque nationale de France, Français 3575, f56r (Gallica
btv1b90605406). - The cipher
- A page wholly in numbers, 43 codes all letters, two homophones per letter (18 to 61).
- How it was read
- Lasry recovered the key from the ciphertext alone. The spot-check decoded line 20 as lvy vovlez procvrer, matching his excerpt.
- What it says
- The writer asks the recipient to see to Clermont and to obtain a favour for a worthy man, without exposing him to attack from those of the religion.
- Credit
- George Lasry, with ChatGPT Astra 6 and Anthropic Opus 5.5 (BnF cipher research, 10 October 2026). This project only spot-checked one sample against the image.
01 Verification
Spot-check against the manuscript
This result is George Lasry’s. This project did not re-solve the cipher: it checked one sample against the Gallica image and recorded what it found.
- Batch A. Image checked: https://gallica.bnf.fr/ark:/12148/btv1b90605406/f116.item
- Folio matches the report: yes; cipher present: yes
- What we checked: f56r line 20: "27 58 60 36 52 58 27 44 61 53 55 30 42 36 33 22 55" = l u y v o u l e z p r o c u r e r = "lvy vovlez procvrer", matches his L19-22 excerpt
- Verdict: confirmed (method key recovered from ciphertext-only, extent complete). The check is a sample, not a re-solution.
- Notes: Page is all-cipher numeric (two homophones per letter, 18-61). Sender/recipient/date unknown; mentions Montgomery and Clermont (Wars of Religion, c.1560s-70s).
Full texts
The transcription and the decryption of every document on this page, so that the reading can be used and checked. Short files are shown here; all are in the repository.
George Lasry's decipherment (report PDF, 24 Oct 2026)
The proposed surrender of the château of Clermont to the comte de Montgomery, the danger of alienating the religious party, and a recommendation for a judicial appointment; sender, recipient and date not identified (Wars of Religion), as given in George Lasry's report.
Decryption: in full above, in George Lasry’s decipherment (readable.md)
Reading: in full above, in George Lasry’s decipherment (readable.md)
Translation: in full above, in George Lasry’s decipherment (translation_excerpt.md)
02 Sources
- George Lasry, with ChatGPT Astra 6 and Anthropic Opus 5.5, BnF cipher research, 10 October 2026 (sent to Daniel Bourdeau on 13 October 2026 for publication here), p. 10; his other items are listed on his contributor card.
- The working folder:
targets/fr3575f56/(his entry as extracted from the report, our spot-check,profile.json).