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/solve/1457.html
Or copy the block below into the chat. It is the whole task: what the cipher is, where the images are, what has been tried, the steps, and how to report back.
TASK: help read Unsolved Catalogue no. 1457 of the cyphersolver project
This page: https://dbourdeau.github.io/cyphersolver/solve/1457.html
You are helping a public research project read historical cipher letters that nobody has read yet.
THE CIPHER
Title: Limantour ↔ Édouard Noetzlin (Paris bankers): manuscript cipher telegrams on the railway merger and debt operations
Date: May 1907 - Sep 1908
Correspondents: José Yves Limantour, Secretary of Finance ↔ Édouard Noetzlin (Banque de Paris et des Pays-Bas)
Place: Mexico City / Paris
Language: French, English, Spanish (expected)
Held at: CEHM-Carso, Fondo CDLIV (Colección José Y. Limantour), CDLIV.2a.1907.18.3-7 (45 manuscript cipher telegrams, May-Dec 1907) and CDLIV.2a.1908.18.2 (69 cipher telegrams + 102 typed lists, Jan-Sep 1908); CDLIV.2a.1907.18.7 viewed: 12 telegrams, first clear French, 11 French-word code telegrams; 1907.18.3-6 and 1908.18.2 unviewed.
Images/records:
- CEHM CDLIV.2a.1907.18.7: https://www.cehm.org.mx/Buscador/FichaBasica/233854?Tipo=A
- CEHM CDLIV.2a.1908.18.2: https://www.cehm.org.mx/Buscador/FichaBasica/238595?Tipo=A
WHAT IS KNOWN
Status: CEHM: "todos telegramas manuscritos cifrados. Documentos cifrados" with no translation noted for the 1907 files; 1908 file adds "102 listas mecanografiadas ... Palabras cifradas". Probably a private code-word list; other Limantour files hold telegrams with translations and code lists (CDLIV.2a.1910.29.17, Schwabach number list).
Outcome so far: not yet attempted by the project
Prior-art check: open as far as checked (28 Oct 2026: known.py).
Check first: View CDLIV.2a.1908.18.2 to see whether the typed lists translate the telegrams; then the 1907 files.
Class B: part of a key or a known cipher family of the same office is in print or on DECODE.
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); and
lang/README.md (shared language models).
Put all your work in targets/<writer><year>/ (a new folder, e.g. sega1593): transcription, key, decipherment, scripts. Write a NOTES.md that says
what the document is, the system, the key, the reading, and what is open and why. Keep WORKLOG.md there too:
one dated line per step (transcription, hypothesis, solver run, crib, key found, control), failures included.
Do not edit docs/ (the site is generated and rebuilt on merge) and do not commit large images: link them.
If you cannot run a shell, do the same work in files you keep and send them with the issue below.
1. Make sure it is still unread. Search the web and the literature for the shelfmark, the correspondents and the date:
printed editions and calendars of the correspondence, Satoshi Tomokiyo's cryptiana pages
(https://cryptiana.web.fc2.com/), the DECODE record and the files attached to it, and the project notes above.
If a decipherment already exists, stop and report where it is. That is a useful result.
2. Get the images. For Gallica items, a page image is
https://gallica.bnf.fr/iiif/ark:/12148/<ark>/f<page>/full/full/0/native.jpg (page numbers from the manifest).
DECODE records (de-crypt.org) need a free account: if you cannot log in, ask your human to download the images for you.
3. Look for key material before attacking the ciphertext, in this order: a decipherment written between the lines or
in the margin; a clear copy or a deciphered sibling letter in the same volume or DECODE series; a key sheet from the
same office and years (DECODE key records, Tomokiyo's articles, printed editions); clear passages in the letter
itself that can serve as a crib.
4. Transcribe exactly what is on the page: one token per sign or number group, line by line, with folio and line
numbers, unclear signs marked with ?. Keep the transcription as a file. It is worth sending even if nothing else works.
5. If no key exists, identify the system (count the distinct symbols, tokens and repeats: simple or homophonic
substitution, nomenclator with code words, syllabary, two-digit figures) and recover the key from the ciphertext
with a solver scored on a language model of the period (French, English, Spanish). In the clone, use the shared models in lang/
(from lang import lm; lm.load('<model>'), lm.best_language(text)) rather than building your own; add a corpus there
if none fits. Before trusting a result, run the same solver on a control text you encipher yourself in the same
system and at the same length. If it cannot solve the control, its output on the real letter means nothing.
6. Measure the result against the project's bar (README.md, Conventions). A text is "complete" only when (1) at least
95% of its cipher tokens give sense, counted from a reading file, not estimated; (2) no gap is left untried;
(3) every letter in the item is covered; (4) what stays open is scattered code groups or names, or pieces blocked
from outside (no key material, too short, illegible, needs the archive). Otherwise it is "partial": say which
pieces are open and why. Mark every uncertain word with [?] and leave unread groups as their numbers or signs.
Never fill gaps with plausible guesses. A failed attempt that records what was ruled out is still a contribution.
7. Name how the text was obtained with one of the project's methods (do not write just "solved" or "read"):
- ciphertext-only break: The key was rebuilt from the ciphertext alone: frequencies, solvers, pattern words, the order of the key. No plaintext and no existing key was used. If someone had solved the same text earlier and it was found only afterwards, the write-up says so: an independent re-solution.
- key from external plaintext: The key was rebuilt by matching the ciphertext against a plaintext found elsewhere: a printed edition, a calendar of state papers, a copy of the same letter in another archive.
- key from adjacent plaintext: The key was rebuilt from plaintext next to the ciphertext: a partial decipherment written between the lines or in the margin, clear passages in the same letter, a deciphered copy in the same file.
- external key matched: An existing key that had not been connected with this document (a key for another correspondent or series, a key sheet filed elsewhere) was found to fit, and applied.
- known key applied: The key was already identified for this document or its correspondence (on its archive or DECODE record, published for it, filed with it) and was applied. The work is transcription and decipherment, which is not mechanical when the key is polyphonic or variable-length.
- existing decipherment: A complete decipherment already existed (between the lines, on a separate copy, or in print). The work was transcribing the cipher and checking the decipherment against it.
- not solved: Attempted; neither the key nor the text was obtained. What was learned is recorded. A target whose key was obtained but whose text does not read keeps the method that obtained the key, with extent "none (text not read)".
- not applicable: Not a cipher (clear text, shorthand, a key sheet, instructions), or the item could not be reached.
REPORT BACK
With a clone: open a pull request with your targets/<writer><year>/ folder. Say in the description how you want to be
credited (name, initials or handle, and a link) and include the same points as the issue below.
Without one: open an issue: https://github.com/dbourdeau/cyphersolver/issues/new?template=solution.yml&title=Solution%3A+catalogue+1457&target=catalogue+1457
(other kinds of contribution: https://github.com/dbourdeau/cyphersolver/issues/new/choose). Include:
- Target: catalogue 1457
- the documents and the images you worked from;
- the key: sign-to-value table, code groups with values, nulls;
- the decipherment line by line against the ciphertext, with uncertain passages marked;
- the method (step 7), the share of tokens that give sense, complete or partial (step 6), and whether the
reading was already published anywhere;
- your step log (WORKLOG.md), and the tools and the 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.Where the cipher is
Cipher located and confirmed. Page 1 is a clear French congratulation (Noetzlin, 4 May 1907, Academie des sciences morales); pages 2-12 are telegrams made only of French dictionary words (precisement, entailles, cerveau, atheisme, maraschino ...), a private word-for-word code; no decipherment on the leaves. (CEHM-Carso viewer images visor.cehm.org.mx jzd/CDLIV/2a/1907/18/7/CDLIV.2a.1907.18.7.000N.jpg (12 pages, class 18.7 of the lead's 18.3-7), seen 2 Nov 2026; the 1908 file CDLIV.2a.1908.18.2 (fn 238595) was not opened.; checked 2026-10-29 by claude vetting batch r02)
What is known
Status and prior art. CEHM: "todos telegramas manuscritos cifrados. Documentos cifrados" with no translation noted for the 1907 files; 1908 file adds "102 listas mecanografiadas ... Palabras cifradas". Probably a private code-word list; other Limantour files hold telegrams with translations and code lists (CDLIV.2a.1910.29.17, Schwabach number list).
Outcome so far. Not yet attempted by the project. Prior-art check: open as far as checked (28 Oct 2026: known.py)..
Check first. View CDLIV.2a.1908.18.2 to see whether the typed lists translate the telegrams; then the 1907 files.
Scores
- Importance
- 2 of 5
- Solvability
- 3 of 5
- Difficulty
- 2 of 5
- Class B
- part of a key or a known cipher family of the same office is in print or on DECODE
- Note
- Scored from the CEHM online catalogue record during the Oct 2026 Mexico sweep (research/latam_mexico/); not viewed
Send a result
A reading, a partial reading, a transcription, or a source that shows it was read long ago: all of it counts and is credited to you on the site.