Read further · read – · key from adjacent plaintext · partial

Lord Cobham at Ostend to Walsingham, 20–22 March 1588

Two letters of the peace commissioner and a Middelburg report (BL Harley MS 287 ff. 70–72), catalogued with no sender or recipient. The cipher is a simple substitution in graphic signs; the key was recovered from the clear English around the cipher runs. Most runs are deciphered: Parma’s new canal to Sluys, a weak garrison, and Cobham’s refusal of “an irreligious peace”.

Date
1588
Read now
– of the cipher tokens give sense
Write-up
harley287.html
Files
targets/harley287
Open gaps
not yet tried ×4no key known ×2too short to break

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/harley287.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: Lord Cobham at Ostend to Walsingham, 20–22 March 1588
This page: https://dbourdeau.github.io/cyphersolver/further/harley287.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/harley287.html (read it first: how the text was read, the key, the reading)
  Date:       1588
  Outcome:    key from adjacent plaintext · partial
  Read now:   not measured
  Files:      https://github.com/dbourdeau/cyphersolver/tree/main/targets/harley287 (NOTES.md, key, transcription, reading, scripts)

OPEN GAPS (from NOTES.md, "## Remaining gaps")
  1. [no-key-material: needs a new source] code number 42, f. 70r ("15 will never yield to send 42 hither") - blocker: no-key-material; occurs once, context allows commissioners or forces
  2. [no-key-material: needs a new source] code sign .7. before "ships", f. 70r - blocker: no-key-material; read as the Queen from context (C), not confirmed by a second occurrence
  3. [not-attempted: doable now] the Jesuit's surname on f. 71r (+∪∧∧..#7, read Bastune?) - blocker: not-attempted; no glyph-level transcription of the word yet, and no printed source searched for a Jesuit sent post to Italy in March 1588
  4. [not-attempted: doable now] one verb on f. 70r ("will not [keep them] from") - blocker: not-attempted; conjectured from context, not re-read sign by sign
  5. [not-attempted: doable now] scattered words marked … or (?) on ff. 70v, 71r, 72r and 72v - blocker: not-attempted; the reading was done word by word from crops, with no sign-by-sign transcription to retry them against the key
  6. [not-attempted: doable now] share of cipher tokens read - blocker: not-attempted; never measured. Next step: transcribe ff. 70r–72v sign by sign into a file and measure the reading against it (`docs/_check_profile.py --measure`)
  7. [too-short: needs a new source] f. 11 (R8477), a different code of about eight groups - blocker: too-short; no key on DECODE or in the volume, too few groups to rebuild one

ALREADY TRIED (from NOTES.md, "## Escalation")
  [x] siblings: catalogue 131 (R8490–R8496, `targets/cobham1588/`) is the same cipher; its glosses on f. 89 (R8493) confirm the letter values; needham1587 (ff. 39–40) and the key R8497 in the same volume checked, different systems
  [x] clear-pages: none of the seven leaves carries an interlinear, marginal or separate decipherment; the clear passages are the letters' own text
  [x] known-keys: Bodley's key R8497 (1590) tried, a different alphabet; the cobham1588 key is this key, merged sign by sign; neither gives 42 or .7.
  [x] print: CSP Foreign vol. 21 pt 4 (March 1588 sections) checked; it calendars other Cobham letters from SP 77, not these, and prints no decipherment
  [x] key-rebuild: key built by hand from clear-text cribs (commaunded to attend, under colour thereof, any money, instructions); nomenclator 15 and □ fixed from context
  [ ] retry: not done; the open words and the doubtful readings have not been re-run sign by sign, because no glyph-level transcription exists yet

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/harley287/NOTES.md in full, and the
   key, transcription and reading files it names; lang/README.md (shared language models).
   Work in targets/harley287/. 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/harley287/. 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+harley287&page=harley287.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