972Cyphersolver

Unsolved Catalogue · no. 747 · class C · priority 6.5 · open

Philip IV → his ambassadors in Rome (Cardinal Albornoz, Antonio Briceño Ronquillo, conde de Oñate, duque del Infantado): cipher letters and letters partly in cipher, 1643-1652

About seventy royal cipher letters to the Rome embassy (conclave, cardinals' pensions, Naples 1647-48); the deciphered siblings make a key rebuild likely.

Date
1643-1652
Correspondents
Philip IV (and Peñaranda) → Cardinal Gil de Albornoz, Antonio Briceño Ronquillo, Íñigo Vélez de Guevara conde de Oñate, VII duque del Infantado
Place
Madrid
Language
Spanish
Held at
AHNOB, OSUNA,CT.2,D.16; OSUNA,CT.2,D.20(1-3); OSUNA,CT.2,D.32(1-2); OSUNA,CT.11,D.1(1-6); OSUNA,C.1978,D.9; OSUNA,C.1978,D.10; OSUNA,C.1978,D.39; OSUNA,C.1978,D.40; OSUNA,C.1978,D.41; OSUNA,C.1978,D.52; OSUNA,C.1978,D.54; OSUNA,C.1978,D.55(1-2); OSUNA,C.1978,D.56; OSUNA,C.1979,D.12; OSUNA,C.1979,D.13; OSUNA,C.1979,D.15; OSUNA,C.1979,D.17; OSUNA,C.1979,D.18; OSUNA,C.1979,D.20; OSUNA,C.1979,D.21; OSUNA,C.1979,D.22; OSUNA,C.1979,D.23; OSUNA,C.1979,D.33; OSUNA,C.1979,D.37; OSUNA,C.1979,D.38; OSUNA,C.1979,D.50; OSUNA,C.1979,D.58; OSUNA,C.1979,D.59; OSUNA,C.1979,D.60; OSUNA,C.1979,D.64; OSUNA,C.1979,D.72; OSUNA,C.1979,D.80; OSUNA,C.1980,D.22; OSUNA,C.1980,D.23; OSUNA,C.1980,D.25; OSUNA,C.1980,D.26; OSUNA,C.1980,D.27(1-7); OSUNA,C.1981,D.4; OSUNA,C.1981,D.14; OSUNA,C.1981,D.15; OSUNA,C.1981,D.22; OSUNA,C.1981,D.26; OSUNA,C.1981,D.27; OSUNA,C.1981,D.28; OSUNA,C.1981,D.37; OSUNA,C.1981,D.51; OSUNA,C.1981,D.52; OSUNA,C.1981,D.69; OSUNA,C.1981,D.70; OSUNA,C.1981,D.75; OSUNA,C.1981,D.76; OSUNA,C.1981,D.81; OSUNA,C.1981,D.83; OSUNA,C.1981,D.88; OSUNA,C.1981,D.93; OSUNA,C.1981,D.96; OSUNA,C.1981,D.97; OSUNA,C.1981,D.109; OSUNA,C.1981,D.120; OSUNA,C.1981,D.130; OSUNA,C.1981,D.133; OSUNA,C.1982,D.5; OSUNA,C.1982,D.6; OSUNA,C.1982,D.9; OSUNA,C.1982,D.12; OSUNA,C.1982,D.15; OSUNA,C.1982,D.20; OSUNA,C.1983,D.7; OSUNA,C.1983,D.9 · 69 items; images online for 4 of 69
Images
PARES 3939415 (OSUNA,CT.2,D.16) · PARES 3938842 (OSUNA,CT.2,D.20(1-3)) · PARES 3939398 (OSUNA,CT.2,D.32(1-2)) · PARES 3939336 (OSUNA,CT.11,D.1(1-6)) · PARES 3939010 (OSUNA,C.1978,D.9) · PARES 3939489 (OSUNA,C.1978,D.10) · PARES 3939035 (OSUNA,C.1978,D.39) · PARES 3939037 (OSUNA,C.1978,D.40) · PARES 3939038 (OSUNA,C.1978,D.41) · PARES 3939142 (OSUNA,C.1978,D.52) · PARES 3939159 (OSUNA,C.1978,D.54) · PARES 3939160 (OSUNA,C.1978,D.55(1-2)) · PARES 3939161 (OSUNA,C.1978,D.56) · PARES 3939014 (OSUNA,C.1979,D.12) · PARES 3939015 (OSUNA,C.1979,D.13) · PARES 3939017 (OSUNA,C.1979,D.15) · PARES 3939019 (OSUNA,C.1979,D.17) · PARES 3939020 (OSUNA,C.1979,D.18) · PARES 3939023 (OSUNA,C.1979,D.20) · PARES 3939024 (OSUNA,C.1979,D.21) · PARES 3939025 (OSUNA,C.1979,D.22) · PARES 3939026 (OSUNA,C.1979,D.23) · PARES 3939154 (OSUNA,C.1979,D.33) · PARES 3939243 (OSUNA,C.1979,D.37) · PARES 3939244 (OSUNA,C.1979,D.38) · PARES 3939285 (OSUNA,C.1979,D.50) · PARES 3939293 (OSUNA,C.1979,D.58) · PARES 3922130 (OSUNA,C.1979,D.59) · PARES 3939318 (OSUNA,C.1979,D.60) · PARES 3939322 (OSUNA,C.1979,D.64) · PARES 3939265 (OSUNA,C.1979,D.72) · PARES 3939274 (OSUNA,C.1979,D.80) · PARES 3939213 (OSUNA,C.1980,D.22) · PARES 3939214 (OSUNA,C.1980,D.23) · PARES 3939216 (OSUNA,C.1980,D.25) · PARES 3939217 (OSUNA,C.1980,D.26) · PARES 3939170 (OSUNA,C.1980,D.27(1-7)) · PARES 3939167 (OSUNA,C.1981,D.4) · PARES 3939086 (OSUNA,C.1981,D.14) · PARES 3939087 (OSUNA,C.1981,D.15) · PARES 3939095 (OSUNA,C.1981,D.22) · PARES 3939099 (OSUNA,C.1981,D.26) · PARES 3939100 (OSUNA,C.1981,D.27) · PARES 3939101 (OSUNA,C.1981,D.28) · PARES 3939164 (OSUNA,C.1981,D.37) · PARES 3939115 (OSUNA,C.1981,D.51) · PARES 3939116 (OSUNA,C.1981,D.52) · PARES 3939261 (OSUNA,C.1981,D.69) · PARES 3939262 (OSUNA,C.1981,D.70) · PARES 3939296 (OSUNA,C.1981,D.75) · PARES 3939297 (OSUNA,C.1981,D.76) · PARES 3939302 (OSUNA,C.1981,D.81) · PARES 3939304 (OSUNA,C.1981,D.83) · PARES 3939331 (OSUNA,C.1981,D.88) · PARES 3939235 (OSUNA,C.1981,D.93) · PARES 3939238 (OSUNA,C.1981,D.96) · PARES 3939239 (OSUNA,C.1981,D.97) · PARES 3939225 (OSUNA,C.1981,D.109) · PARES 3939067 (OSUNA,C.1981,D.120) · PARES 3939079 (OSUNA,C.1981,D.130) · PARES 3939082 (OSUNA,C.1981,D.133) · PARES 3938431 (OSUNA,C.1982,D.5) · PARES 3938432 (OSUNA,C.1982,D.6) · PARES 3938435 (OSUNA,C.1982,D.9) · PARES 3939281 (OSUNA,C.1982,D.12) · PARES 3938441 (OSUNA,C.1982,D.15) · PARES 3938445 (OSUNA,C.1982,D.20) · PARES 3939222 (OSUNA,C.1983,D.7) · PARES 3939224 (OSUNA,C.1983,D.9)

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/747.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. 747 of the cyphersolver project
This page: https://dbourdeau.github.io/cyphersolver/solve/747.html

You are helping a public research project read historical cipher letters that nobody has read yet.

THE CIPHER
  Title:          Philip IV → his ambassadors in Rome (Cardinal Albornoz, Antonio Briceño Ronquillo, conde de Oñate, duque del Infantado): cipher letters and letters partly in cipher, 1643-1652
  Date:           1643-1652
  Correspondents: Philip IV (and Peñaranda) → Cardinal Gil de Albornoz, Antonio Briceño Ronquillo, Íñigo Vélez de Guevara conde de Oñate, VII duque del Infantado
  Place:          Madrid
  Language:       Spanish (expected)
  Held at:        AHNOB, OSUNA,CT.2,D.16; OSUNA,CT.2,D.20(1-3); OSUNA,CT.2,D.32(1-2); OSUNA,CT.11,D.1(1-6); OSUNA,C.1978,D.9; OSUNA,C.1978,D.10; OSUNA,C.1978,D.39; OSUNA,C.1978,D.40; OSUNA,C.1978,D.41; OSUNA,C.1978,D.52; OSUNA,C.1978,D.54; OSUNA,C.1978,D.55(1-2); OSUNA,C.1978,D.56; OSUNA,C.1979,D.12; OSUNA,C.1979,D.13; OSUNA,C.1979,D.15; OSUNA,C.1979,D.17; OSUNA,C.1979,D.18; OSUNA,C.1979,D.20; OSUNA,C.1979,D.21; OSUNA,C.1979,D.22; OSUNA,C.1979,D.23; OSUNA,C.1979,D.33; OSUNA,C.1979,D.37; OSUNA,C.1979,D.38; OSUNA,C.1979,D.50; OSUNA,C.1979,D.58; OSUNA,C.1979,D.59; OSUNA,C.1979,D.60; OSUNA,C.1979,D.64; OSUNA,C.1979,D.72; OSUNA,C.1979,D.80; OSUNA,C.1980,D.22; OSUNA,C.1980,D.23; OSUNA,C.1980,D.25; OSUNA,C.1980,D.26; OSUNA,C.1980,D.27(1-7); OSUNA,C.1981,D.4; OSUNA,C.1981,D.14; OSUNA,C.1981,D.15; OSUNA,C.1981,D.22; OSUNA,C.1981,D.26; OSUNA,C.1981,D.27; OSUNA,C.1981,D.28; OSUNA,C.1981,D.37; OSUNA,C.1981,D.51; OSUNA,C.1981,D.52; OSUNA,C.1981,D.69; OSUNA,C.1981,D.70; OSUNA,C.1981,D.75; OSUNA,C.1981,D.76; OSUNA,C.1981,D.81; OSUNA,C.1981,D.83; OSUNA,C.1981,D.88; OSUNA,C.1981,D.93; OSUNA,C.1981,D.96; OSUNA,C.1981,D.97; OSUNA,C.1981,D.109; OSUNA,C.1981,D.120; OSUNA,C.1981,D.130; OSUNA,C.1981,D.133; OSUNA,C.1982,D.5; OSUNA,C.1982,D.6; OSUNA,C.1982,D.9; OSUNA,C.1982,D.12; OSUNA,C.1982,D.15; OSUNA,C.1982,D.20; OSUNA,C.1983,D.7; OSUNA,C.1983,D.9; 69 items; images online for 4 of 69
  Images/records:
    - PARES 3939415 (OSUNA,CT.2,D.16): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939415
    - PARES 3938842 (OSUNA,CT.2,D.20(1-3)): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3938842
    - PARES 3939398 (OSUNA,CT.2,D.32(1-2)): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939398
    - PARES 3939336 (OSUNA,CT.11,D.1(1-6)): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939336
    - PARES 3939010 (OSUNA,C.1978,D.9): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939010
    - PARES 3939489 (OSUNA,C.1978,D.10): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939489
    - PARES 3939035 (OSUNA,C.1978,D.39): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939035
    - PARES 3939037 (OSUNA,C.1978,D.40): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939037
    - PARES 3939038 (OSUNA,C.1978,D.41): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939038
    - PARES 3939142 (OSUNA,C.1978,D.52): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939142
    - PARES 3939159 (OSUNA,C.1978,D.54): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939159
    - PARES 3939160 (OSUNA,C.1978,D.55(1-2)): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939160
    - PARES 3939161 (OSUNA,C.1978,D.56): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939161
    - PARES 3939014 (OSUNA,C.1979,D.12): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939014
    - PARES 3939015 (OSUNA,C.1979,D.13): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939015
    - PARES 3939017 (OSUNA,C.1979,D.15): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939017
    - PARES 3939019 (OSUNA,C.1979,D.17): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939019
    - PARES 3939020 (OSUNA,C.1979,D.18): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939020
    - PARES 3939023 (OSUNA,C.1979,D.20): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939023
    - PARES 3939024 (OSUNA,C.1979,D.21): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939024
    - PARES 3939025 (OSUNA,C.1979,D.22): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939025
    - PARES 3939026 (OSUNA,C.1979,D.23): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939026
    - PARES 3939154 (OSUNA,C.1979,D.33): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939154
    - PARES 3939243 (OSUNA,C.1979,D.37): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939243
    - PARES 3939244 (OSUNA,C.1979,D.38): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939244
    - PARES 3939285 (OSUNA,C.1979,D.50): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939285
    - PARES 3939293 (OSUNA,C.1979,D.58): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939293
    - PARES 3922130 (OSUNA,C.1979,D.59): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3922130
    - PARES 3939318 (OSUNA,C.1979,D.60): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939318
    - PARES 3939322 (OSUNA,C.1979,D.64): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939322
    - PARES 3939265 (OSUNA,C.1979,D.72): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939265
    - PARES 3939274 (OSUNA,C.1979,D.80): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939274
    - PARES 3939213 (OSUNA,C.1980,D.22): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939213
    - PARES 3939214 (OSUNA,C.1980,D.23): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939214
    - PARES 3939216 (OSUNA,C.1980,D.25): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939216
    - PARES 3939217 (OSUNA,C.1980,D.26): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939217
    - PARES 3939170 (OSUNA,C.1980,D.27(1-7)): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939170
    - PARES 3939167 (OSUNA,C.1981,D.4): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939167
    - PARES 3939086 (OSUNA,C.1981,D.14): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939086
    - PARES 3939087 (OSUNA,C.1981,D.15): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939087
    - PARES 3939095 (OSUNA,C.1981,D.22): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939095
    - PARES 3939099 (OSUNA,C.1981,D.26): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939099
    - PARES 3939100 (OSUNA,C.1981,D.27): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939100
    - PARES 3939101 (OSUNA,C.1981,D.28): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939101
    - PARES 3939164 (OSUNA,C.1981,D.37): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939164
    - PARES 3939115 (OSUNA,C.1981,D.51): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939115
    - PARES 3939116 (OSUNA,C.1981,D.52): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939116
    - PARES 3939261 (OSUNA,C.1981,D.69): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939261
    - PARES 3939262 (OSUNA,C.1981,D.70): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939262
    - PARES 3939296 (OSUNA,C.1981,D.75): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939296
    - PARES 3939297 (OSUNA,C.1981,D.76): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939297
    - PARES 3939302 (OSUNA,C.1981,D.81): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939302
    - PARES 3939304 (OSUNA,C.1981,D.83): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939304
    - PARES 3939331 (OSUNA,C.1981,D.88): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939331
    - PARES 3939235 (OSUNA,C.1981,D.93): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939235
    - PARES 3939238 (OSUNA,C.1981,D.96): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939238
    - PARES 3939239 (OSUNA,C.1981,D.97): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939239
    - PARES 3939225 (OSUNA,C.1981,D.109): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939225
    - PARES 3939067 (OSUNA,C.1981,D.120): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939067
    - PARES 3939079 (OSUNA,C.1981,D.130): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939079
    - PARES 3939082 (OSUNA,C.1981,D.133): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939082
    - PARES 3938431 (OSUNA,C.1982,D.5): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3938431
    - PARES 3938432 (OSUNA,C.1982,D.6): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3938432
    - PARES 3938435 (OSUNA,C.1982,D.9): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3938435
    - PARES 3939281 (OSUNA,C.1982,D.12): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939281
    - PARES 3938441 (OSUNA,C.1982,D.15): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3938441
    - PARES 3938445 (OSUNA,C.1982,D.20): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3938445
    - PARES 3939222 (OSUNA,C.1983,D.7): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939222
    - PARES 3939224 (OSUNA,C.1983,D.9): https://pares.cultura.gob.es/ParesBusquedas20/catalogo/description/3939224

WHAT IS KNOWN
  Status: PARES hits (27 Oct 2026, "carta cifrada"/"cifrada"/"parte en cifra"). Same Osuna embassy series as the Infantado 1650 row (OSUNA,C.1981,D.113) and the dropped 1642-45 letters with deciphered copies (OSUNA,CT.7; CT.2,D.6, D.8, D.13). PARES full-text search matches words, not the phrase, so a term hit is a pointer; the hit-list title says the letter is in cipher, not whether a decipherment is filed with it. Not in the repo (known.py: no hits for Albornoz, C.1978, C.1979).
  Outcome so far: not yet attempted by the project
  Prior-art check: not searched (title screening only); see the Infantado 1650 row (embassy studied, nothing on its ciphers).
  Check first: Open a sample of descriptions and check images (many hit rows show no image icon); pair with the deciphered OSUNA letters of 1642-45 as cribs.
  Class C: no key and no deciphered sibling is known, so expect a ciphertext-only attack.

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 (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+747&target=catalogue+747
(other kinds of contribution: https://github.com/dbourdeau/cyphersolver/issues/new/choose). Include:
  - Target: catalogue 747
  - 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.

What is known

Status and prior art. PARES hits (27 Oct 2026, "carta cifrada"/"cifrada"/"parte en cifra"). Same Osuna embassy series as the Infantado 1650 row (OSUNA,C.1981,D.113) and the dropped 1642-45 letters with deciphered copies (OSUNA,CT.7; CT.2,D.6, D.8, D.13). PARES full-text search matches words, not the phrase, so a term hit is a pointer; the hit-list title says the letter is in cipher, not whether a decipherment is filed with it. Not in the repo (known.py: no hits for Albornoz, C.1978, C.1979).

Outcome so far. Not yet attempted by the project. Prior-art check: not searched (title screening only); see the Infantado 1650 row (embassy studied, nothing on its ciphers)..

Check first. Open a sample of descriptions and check images (many hit rows show no image icon); pair with the deciphered OSUNA letters of 1642-45 as cribs.

Scores

Importance
3 of 5
Solvability
4 of 5
Difficulty
2 of 5
Class C
no key and no deciphered sibling is known, so expect a ciphertext-only attack
Note
Scored from the PARES hit list (title, dates, signatura only) during the 27 Oct 2026 PARES batch (research/pares_ags/, screen.py + reading of the top of screen_ranked.tsv); full description and images 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.

Open a solution issueOther kinds of reportHow credit works← All unsolved ciphers