01 The letter
| Shelfmark | BnF Dupuy 61 · Méry de Vic, f43r |
|---|---|
| Sender | Méry de Vic |
| Recipient | Henri IV |
| Date | 28 August 1589 |
| Language | French |
| Report status | 6/6 pages transcribed; Partly deciphered |
| Ciphertext | 545 elements, 523 identified (96.0%) |
02 The key
81 symbols: 50 alphabet signs, 8 nomenclature signs, 3 nulls, 20 unidentified types The key was recovered from the ciphertext alone.
03 The decipherment
f43r
? assembler à huict lieues de ceste ville. Leur troupe ? au plus de douze cents hommes? de pied? et deux cents chevaux et doivent meiner deux ou trois pieces.
Translation. ? to assemble eight leagues from this town. Their force ? at most twelve hundred men? on foot? and two hundred horsemen, and they must bring two or three guns.
f43r
? qui avoit tenu le feu Roy en esperance de le servir, s’est déclaré comme plusieurs du ? m’ont asseuré. Il ? amas d’homes et se delibere de
Translation. ?, who had kept the late King hoping to serve him, has declared himself, as several of ? have assured me. He ? a gathering of men and intends to
04 Our check
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/btv1b103164206/f95.item
- Folio matches the report: yes; cipher present: yes
- What we checked: f43r: cleartext opening (Pompadour, Clermont Vertillac) + cipher block match his description; clear words between cipher runs read "...= roy q2 change come on ma asseure ... assemble aussi" whereas his excerpt gives "s est declare comme plusieurs du ? m ont asseure"; symbol-level decode not completed
- Verdict: partly confirmed (method key recovered from ciphertext-only, extent partial). The check is a sample, not a re-solution.
- Notes: Excerpt clear-text words do not exactly match the MS clear words (change come on ma asseure); 96% identified, status Partly deciphered; worth rechecking that excerpt line.
05 Notes and corrections
One excerpt line disagrees with the manuscript. Lasry gives "s'est déclaré comme plusieurs du ? m'ont asseuré"; the clear words on f43r read "… roy q2 change come on ma asseure". The other clear words and the cipher block match. That line should be checked again.
06 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. 4; his other items are listed on his contributor card.
- The working folder:
targets/meryvic1589/(his entry as extracted from the report, our spot-check,profile.json).