Read further · read 76.1% · key from external plaintext · partial

Giovanni Mazzinghi and an unsigned writer to the Medici, Rome, January 1478 (1479)

Two bare cipher letters from Rome to the Medici in the winter after the Pazzi conspiracy, the first of them warning of a bull annulling the Church’s privileges and of a plot named by two Pistoiese. The key was fitted on the contemporary decipherment of a sibling letter and checked by an independent ciphertext-only break: 76.1% of 1,647 signs read, the key partial.

Date
1478–79
Read now
76.1% of the cipher tokens give sense
Write-up
mazzinghi1478.html
Files
targets/mazzinghi1478
Open gaps
hard to read on the scanno key known

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/mazzinghi1478.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: Giovanni Mazzinghi and an unsigned writer to the Medici, Rome, January 1478 (1479)
This page: https://dbourdeau.github.io/cyphersolver/further/mazzinghi1478.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/mazzinghi1478.html (read it first: how the text was read, the key, the reading)
  Date:       1478–79
  Outcome:    key from external plaintext · partial
  Read now:   76.1% of the deciphered cipher tokens give sense (pieces below may be untouched)
  Files:      https://github.com/dbourdeau/cyphersolver/tree/main/targets/mazzinghi1478 (NOTES.md, key, transcription, reading, scripts)

OPEN GAPS (from NOTES.md, "## Remaining gaps")
  1. [illegible: needs a new source] 92 cipher words (394 signs) that do not decode to sense, listed in `measure.py` (UNREAD) - blocker: illegible; signs are 8-14 px at the ASF server's maximum (1272 px), rechecked at 5-6x (`recheck.tsv`) and tried against look-alike variants (`variants.py`); no higher-resolution image online
  2. [no-key-material: needs a new source] code numerals 10, 30, 40, 51, 231, 10/3 and the recurring group OLDP/DLDP/EDP - blocker: no-key-material; only 12 = Zanobi is glossed in LXXII 170, and the gloss over 10 reads "Duca" plus an illegible word (re-read at 6x, 6 Nov: "nostro"?, not "di Calabria"); none of the Medici key sheets of 1472-1494 (MAP LXXII 178-189 bis, CXIX 115-127, LXXII 172, 209-210, CXXIV 184) is this cipher or holds its code list (`keysheets.md`)

ALREADY TRIED (from NOTES.md, "## Escalation")
  [x] siblings: LXXII 170 (glossed) used as key source; LXXII 169, 171 and CXXXVII 251, 253 opened (171 is another system)
  [x] clear-pages: none filed with 142 or 252; the 142 verso is the endorsement only
  [x] known-keys: siena11 (Acciaiuoli, Rome 1478) compared, a different system; every Medici key sheet of the period checked (MAP LXXII 178-189 bis, CXIX 115-127 and others, `keysheets.md`): none is this cipher
  [x] print: Lorenzo de' Medici, Lettere II-IV searched for the shelfmarks (Chrome passes c32, c33): no citation; web search for Mazzinghi and the Pistoiese plot found nothing
  [x] key-rebuild: hard-EM on the gloss pairs (build_key.py), LM fill (refine.py), context fixes, image recheck (recheck.tsv)
  [x] retry: every unread word retried with look-alike variants against a period word list (variants.py)

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/mazzinghi1478/NOTES.md in full, and the
   key, transcription and reading files it names; lang/README.md (shared language models).
   Work in targets/mazzinghi1478/. 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/mazzinghi1478/. 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+mazzinghi1478&page=mazzinghi1478.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