Read further · read 99.4% · external key matched · partial

Marie de Médicis to Savary de Brèves, Rome, 1610

Two short ciphered passages in the regent’s letters of 15 September and 10 November 1610 (BnF fr. 3789 ff. 17r, 19r). Brice Dudout deciphered them with Henri IV’s 1610 key for Brèves, which is on BnF fr. 3462 view 112 (R2077’s note mistypes it as 3642). Checked here sign by sign: 96 of 98 glyphs supported, two signs conflict with the table. George Lasry contributed his CTTS key, with a repeat sign, and a second document in the same key (PR #61).

Date
1610
Read now
99.4% of the cipher tokens give sense
Write-up
breves1610.html
Files
targets/breves1610
Open gaps
no key known ×2hard to read on the scan

Hand this page to your AI agent

Give your agent (Claude, ChatGPT or any assistant that can open web pages) this address and ask it to do the task on the page:

https://dbourdeau.github.io/cyphersolver/further/breves1610.html

Or copy the block below into the chat. It is the whole task: the reading, every open gap, what has been tried, the steps, and how to report back.

TASK: take a partial decipherment further: Marie de Médicis to Savary de Brèves, Rome, 1610
This page: https://dbourdeau.github.io/cyphersolver/further/breves1610.html

You are helping a public research project finish reading historical cipher letters. This one is read in part:
the key works, but some pieces are still open. Your job is to close one or more of the open gaps below.

THE READING
  Write-up:   https://dbourdeau.github.io/cyphersolver/breves1610.html (read it first: how the text was read, the key, the reading)
  Date:       1610
  Outcome:    external key matched · partial
  Read now:   99.4% of the deciphered cipher tokens give sense (pieces below may be untouched)
  Files:      https://github.com/dbourdeau/cyphersolver/tree/main/targets/breves1610 (NOTES.md, key, transcription, reading, scripts)

OPEN GAPS (from NOTES.md, "## Remaining gaps")
  1. [no-key-material: needs a new source] 10 Nov, re[c?]ognoissant, one sign (B1 on view 112, c needed) - blocker: no-key-material; Lasry's CTTS key (PR #61) gives this sign C from this word only; his longer document does not use it, so the table conflict stands
  2. [illegible: needs a new source] 15 Sept, acompagne[z?]/acompagnee, one sign (E3 or Z2) - blocker: illegible; the two cells differ by a stroke and the crop does not settle it
  3. [no-key-material: needs a new source] barred 72, 79, 86, 90 (6 occurrences) - blocker: no-key-material; the N-Z page of the key is not in hand; values as corroborated by Tomokiyo and, independently, in Lasry's CTTS key (72̄ que, 79̄ re, 86̄ se, 90̄ tion; PR #61)

ALREADY TRIED (from NOTES.md, "## Escalation")
  [x] siblings: R2077 (Henri IV to Brèves, 5 Jan 1610) is the key's own letter; Lasry supplied his CTTS key and a second document in the key (PR #61, 21 Oct 2026), which settles the repeat sign; whether that document is R2077 is not established
  [x] clear-pages: f. 17v/19v hold show-through only; Brèves's reply of 9 Dec 1610 (Cinq cents de Colbert 351) paraphrases
  [x] known-keys: the Villeroy 1605 code (fr. 3789 f. 26) ruled out on 21 Sept; fr. 3462 view 112 fits
  [x] print: Tomokiyo louisxiii.htm and DECODE list both as not deciphered; no edition found
  [x] retry: every glyph re-read against view 112 (alignment.tsv), 20 Oct 2026; regraded 21 Oct 2026 against Lasry's CTTS key (second s = repeat sign)

STEPS
0. Set up. If you can run a shell, fork and clone the repository and work inside it:
     git clone https://github.com/dbourdeau/cyphersolver.git
   Then read, in this order: CONTRIBUTING.md (how a contribution is sent and credited); README.md, sections
   "Repository layout" and "Conventions" (how readings are measured and named); targets/breves1610/NOTES.md in full, and the
   key, transcription and reading files it names; lang/README.md (shared language models).
   Work in targets/breves1610/. Add your findings to NOTES.md under a dated heading without rewriting what is there, and
   update the "## Remaining gaps" line of every gap you close. Keep WORKLOG.md there: one dated line per step
   (hypothesis, value tried, solver run, crib, control), failures included. Do not edit docs/ (the site is generated).
   If you cannot run a shell, fetch the files from the links above and keep your work in files you send with the issue.
1. Pick a gap. Start with the ones marked "doable now" (open-codes, not-attempted, left-open): the images and the key
   are online, so they need only work. A gap marked "needs a new source" (no-key-material, too-short, illegible,
   needs-physical-access) can be closed only by something new: a key
   or a deciphered sibling found elsewhere, a better image, a printed edition or calendar, a photograph from the archive.
   For those, search for that material first, and say where you looked even when you find nothing.
2. Start from the existing key and transcription in the folder. Do not rebuild the key from scratch, and do not
   re-read parts that are already read unless you find an error in them.
3. For a code group or sign value: list every place the group occurs, show how each reads with the value you propose,
   and say what still does not fit. For a passage: re-read it at the image and give the folio and line. For a missing
   letter or leaf: say where it is held and how it can be reached.
4. Measure again. Apply the key to the whole text, write the reading file, and count the share of cipher tokens that
   give sense (not an estimate). The reading is "complete" only when (1) at least 95% of its cipher tokens give sense;
   (2) no gap is left untried; (3) every letter in it is covered; (4) what stays open is scattered code groups or names,
   or pieces blocked from outside. Otherwise it stays "partial": say which gaps are still open and why.
5. Be honest. Mark every uncertain word with [?], leave unread groups as their numbers or signs, and never fill a gap
   with a plausible guess. A gap retried and still open, with what was ruled out, is worth reporting.

REPORT BACK
With a clone: open a pull request with your changes to targets/breves1610/. Say in the description which gaps you worked on,
  the share read before and after, and how you want to be credited (name, initials or handle, and a link).
Without one: open an issue: https://github.com/dbourdeau/cyphersolver/issues/new?template=further-reading.yml&title=Further+reading%3A+breves1610&page=breves1610.html
  Give the write-up, the gap you worked on (its line in Remaining gaps, or the code group, folio and line), what you
  propose, the evidence (every occurrence, the images or sources), the share read before and after, your step log,
  and the tools and AI model you used.
If you cannot open issues or pull requests, write this report for your human to send. Credit goes to the person who sends it.

Open gaps

gold can be done now: the images and the key are online, it needs only work. grey needs a new source first: a key, a better scan, an edition or the archive.

Already tried

Send a result

One closed gap counts: a code group valued, a passage re-read, a key or clear copy found elsewhere. It is credited to you on the write-up.

Open a further-reading issueOther kinds of reportHow credit works← All partial readings