Pacheco to Granvelle, April–June 1554

TASK: take a partial decipherment further: Pacheco to Granvelle, April–June 1554
This page: https://dbourdeau.github.io/cyphersolver/further/siguenza1554.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/siguenza1554.html (read it first: how the text was read, the key, the reading)
  Date:       1554
  Outcome:    key from adjacent plaintext · partial
  Read now:   98.0% of the deciphered cipher tokens give sense (pieces below may be untouched)
  Files:      https://github.com/dbourdeau/cyphersolver/tree/main/targets/siguenza1554 (NOTES.md, key, transcription, reading, scripts)

OPEN GAPS (from NOTES.md, "## Remaining gaps")
  1. [illegible: needs a new source] Look-alike signs: `ꝺ̶` (*te*/*de*/*re*), `ụ` (*c* with an unseen vowel), `ꝸ` (*re*/*co*/*a*), `ꝺ̵` (*se*/*si*), plain `ꝗ` (*que*, *r*, *vo*, *lo*; not separable by shape), and `ʒ` in five places of letters 3-4 that want *do* (probably `ɀ`) keep two values: 85 tokens - blocker: illegible; at 12-15 px a sign the BNE scan does not separate the forms, and it is the only image; a side-by-side comparison on the sharper sibling images did not separate plain `ꝗ` (see Siblings)
  2. [too-short: needs a new source] 11 sign types (14 tokens) without a value (`f`, `ffoꝶ`, `f̈`, `m`, `ova`, `°`, `ŧ`, `ʳ`, `⊳`, `ꝗ̈`, `ꝶ̃`) - blocker: too-short; each is met once or twice where the alignment does not fix a value (`°` may be a null)
  3. [too-short: needs a new source] Code groups seen once (`gua` armada, `troꝶ` guerra, `si` amigos, `ros` su Mag.d; in the siblings `iz` cardenal, `ꝗz` Ingalaterra, `5ı` españoles, `ge` alemanes) and the sibling number `25` (*(ca)vallos*) - blocker: too-short; each valued from the decipherment at its one place
  4. [illegible: needs a new source] d4 J1-J6, K1-K4, single signs read at 2-2.6x - blocker: illegible; the margin text is clear, the scan limits the cipher
  5. [illegible: needs a new source] d4 N1-N5, the interlinear notes transcribed only roughly (*las ven[…]*, *otro[…]* in L1) - blocker: illegible
  6. [too-short: needs a new source] The key's structure (consonant sign plus vowel mark) is inferred; several signs do not follow it - blocker: too-short; most signs occur once or twice

ALREADY TRIED (from NOTES.md, "## Escalation")
  [x] siblings: all six letters of MSS/20214/61 viewed; five carry cipher, all with decipherments of the time. Pacheco's thirteen letters of 1554-1555 in the Real Biblioteca, Madrid (II/2251; H15Corpus GRANVELA-H-0032 to 0044) viewed: four carry cipher in the same key, with decipherments of the time, and are transcribed in `siblings/rb2251/` (37 lines, 626 signs). The volume also holds a letter of the viceroy of Sicily almost wholly in cipher (f. 182r), another correspondence, not worked. Pacheco's other letters to Granvelle in the Real Biblioteca (II/2322, II/2325, II/2258; Rome 1552-1553) are not checked
  [x] clear-pages: the decipherments of the time are on the same pages (interlinear and margin); 61/3 f. 1r has a second photograph with the margin legible
  [x] known-keys: Tomokiyo's list of Spanish ciphers (cached upstream in `targets/vasto1527/prior/spanish2C_now.htm`) searched: no Pacheco or Sigüenza key (its "Cardinal Pacheco" is Francisco Pacheco, a 1566 cipher). Pich-Ponce's PP1-PP3 (Granvelle-Renard, Saint-Mauris) are other ciphers. The structure (base sign plus vowel marks, letter-word codes such as `o-o`) is that of Charles V's syllabic ciphers, as is the Imperial Cipher of 1544-1554 of `vargas1552`, whose short-word codes (`s-o` *el*, `x-o` *del*, `n-o` *al*) have the same shape. No code group is shared among the few known, and that key's full table (Meister 1906, Bertomeu Masiá 2009) is not in the repository, so the identity is not tested
  [x] print: web search (2 Nov 2026): no edition or study of these letters' cipher. Martín Aizpuru, *Onomázein* (2025), studies forty letters of Pacheco and Bolea to Granvelle (1551-1557), but those are in the Real Biblioteca (Granvela collection, H15Corpus), not the BNE, and her study is linguistic. Bucuré, *Estudios Románicos* 34 (2025), studies the Naples cipher of 1547 (Pedro de Toledo), not compared. Van Durme 1956, cited by the BNE record, not seen
  [x] key-rebuild: syllabary rebuilt from the alignment with the decipherments
  [x] retry: letter 1 re-read at full size after the key was built from letters 2-4; look-alikes compared side by side

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/siguenza1554/NOTES.md in full, and the
   key, transcription and reading files it names; lang/README.md (shared language models).
   Work in targets/siguenza1554/. 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/siguenza1554/. 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+siguenza1554&page=siguenza1554.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.