At a glanceKnown key applied · none (key obtained, text not read)
- The letters
- Two Italian letters, sender and recipient unknown, written half in clear and half in code, intercepted in London. They sit in a file dated 1623–24.
- Where
- The National Archives, Kew, SP 106/10 ff. 167–169 and 139–140 (DECODE R664, R660); the codebreaker’s grid f. 125 (R658) and glossed strings f. 182 (R702 p. 2). DECODE lists them as anonymous ciphertexts, “1558/1625”.
- The cipher
- One three-figure group per syllable. Each consonant takes five groups in a row, one per vowel a e i o u; a few groups are whole words, with a superscript letter for the ending.
- How it was deciphered
- About 45 values were aligned from the codebreaker’s syllables written above the groups. His own grid of the code then gave 117 values and corrected four of them.
- What it says
- Fragments: della loro sicurezza, et hoggi terzo giorno quelle de nuovo senza, and on his sheet i colonelli, che possiamo prometter, di 24 di maggio.
- Still open
- Neither letter has been transcribed group by group and decoded through with the table; the writers are not identified. Checked on 23 October 2026: R664’s file holds two decoded phrases and one clear line, not the letter, so R664 is decoded, not read; R658 (the codebreaker’s grid), R702 p. 2 (his worksheet of glossed strings) and R701 p. 1 (his heading and word list) are working papers, not prose. No document of this entry reads yet. The way on is to transcribe R664 and R660 group by group and decode them with the rebuilt code.
- Credit
- The values are the contemporary codebreaker’s.
These letters were one part of a single codebreaker’s working file, which this site first treated as one entry. The file holds several different ciphers, and each now has its own page: the two-figure nomenclator of his key sheet R725 (sp106r725, which also dates the file), a second three-figure code used in a Venetian secretary’s letter of 1625 (sp106r722), a letter-and-figure syllabary (sp106r704), and a 1645 royalist letter that only shares the box (sp106r931).
01The documents
| DECODE | ff. | what it is |
|---|---|---|
| R664 | 167–169 | intercept, ~500 groups in 45 numbered lines, half in clear Italian, glossed between the lines |
| R660 | 139–140 | intercept, 15 lines, solutions above the groups |
| R658 | 125 | the codebreaker’s grid of the code: every group 136–565 with his count below and his value above |
| R702 p. 2 | 182 | his group strings of this code with his glosses |
| R701 p. 1 | 175 | his heading “Wordes marked with letters in the Venetian Cifer” |
DECODE lists each as an undated, anonymous, partly decrypted ciphertext. The other pages of R701 and R702 belong to the 1625 code (sp106r722), apart from a five-line letter cipher on R701 p. 2 (Esg frp rohxog x rygo fa ombhpeip …, about 120 letters), which a substitution solver run against five languages did not break and which is too short to go further.
02Values from the interlinear glosses
R660 and R664 are letters written half in cleartext and half in code. The writer enciphered the words that mattered and left the Italian connecting phrases in clear, which gave the English codebreaker his cribs, and gives them now. One whole line of R664 stands in the clear, and it is about the cipher itself:
“potrete continuare nel modo cominciato, osservando però il [mutamento … alle volte … col … numeri suppositi]”
The codebreaker wrote his solutions above the groups, syllable by syllable. Aligning those syllables against the figures gives the code back. About forty-five values were fixed this way, each by a word that admits no other division (260, 262, 263 and 459 as corrected by his grid, section 04):
252 se · 253 si · 254 so · 260 ta · 261 te · 262 ti · 263 to · 316 ta? · 319 cu · 320 in · 340 lettere
344 el · 356 i · 357 l · 359 n · 366 col · 411 qui · 430 a · 433 la · 434 le · 436 lo · 456 o · 459 r
461 ve · 463 volte · 468 quello · 515 da · 516 de · 518 do · 535 mi · 536 mol · 537 mu · 542 quan · 544 gua · 560 za · 568 vostre
211 433 436 154 253 319 152 560 … with del·la·lo·ro·si·cu·re·za written above: “della loro sicurezza”. Image: The National Archives, Kew, SP 106/10 f. 167, via DECODE R664 (p. 1).With these values line 38 decrypts as follows:
del la lo ro si cu re za ? n do ? la
and lines 41–42, with a word running over the line break:
et (in the clear) quel le de nu o ve se n za
“et hoggi terzo giorno quelle de nuovo senza…”
03Method, and the check that the alignment is sound
All of this depends on matching the codebreaker’s interlinear syllables to the right groups, and a one-group drift would produce plausible nonsense.
The alignment produced one apparent contradiction, and its resolution supports the rest: group 252 was glossed sen in one line and se in another, and 359 za in one line and n in two others.
Both resolve if the word senza runs over the end of line 41 (252 se + 359 n closing the line, 560 za opening line 42), which is what the manuscript shows.
After that correction no value conflicts with any other across lines 34–45.
The images came from DECODE with the project’s login and had to be rotated before transcription. The codebreaker did the cryptanalysis four hundred years ago; the work here was to find the sheets on which he wrote it down, transcribe them and apply them.
04The codebreaker’s own table of “the Venetian Cifer”
Seven more records of the box, which DECODE lists as another set of anonymous ciphertexts (catalogue item 62), are his worksheets. On R701 he heads a list of word groups “Wordes marked with letters in the Venetian Cifer”: 369° nostro, 467° questo, 430a passata. The same words stand in the side column of R658, and R658 is his table of the code of R660 and R664: every group from 136 to 565, with a count of its occurrences below it and his value above it.
The grid shows how the code was made. Each consonant takes five consecutive rows in the order a e i o u, and each hundreds column a different consonant: 151–155 ra…ru, 251–255 sa…su, 351–355 sca…scu, 551–555 sta…stu; 260–264 ta…tu, 360–364 tra…tru, 460–463 va…vo, 560–564 za…zu; 433–437 la…lu, 142–146 na…nu, 242–246 pa…pu, 442–446 pra…pru, 542–545 qua…quo; the row x56 holds the bare vowels, x57–x59 single consonants (357 l, 359 n, 459 r), and a handful of groups are whole words (339 liga, 340 lettere, 439 per, 165 che, 465 quel), their ending given by a superscript letter. With the table, the code has 117 values, 102 of them written by the codebreaker and 15 predicted by the pattern.
The check is R702, where he wrote out group strings with his own glosses. Every one of its 46 groups is in the table, and every string decodes to his gloss:
252 359 518 253 → se·n·do·si “sendosi” · 167 252 459 253 → con·se·r·si “conservarsi”
165 245 556 253 156 526 445 534 261 459 → che·po·s·si·a·mo·pro·me·te·r “che possiamo prometter”
The same sheet glosses di 24 di maggio, del campo, per nome suo, sono capitate and efficacia: the letter he was working on was written in late May and spoke of a camp and of colonels. The table also corrects four values first aligned on R664 alone: 260 is ta, 262 ti, 263 to and 459 r (they had been taken as mento, to, ti and v), and 316 ta does not fit the ca…cu run it stands in.
The 1625 letter of the same file (sp106r722) is in a code built the same way but with another table (R701 p. 3: 244 ra, 245 re, 366–370 la…lu; here 244 is pi, 245 po, 433–437 la…lu). The words R701 lists under “the Venetian Cifer” are the words of R658’s side column, so on the sheets’ own evidence the name belongs to this code.
05Date
No date has been found in these two letters. The file they sit in is dated to 1623–24 by the vocabulary of the codebreaker’s other key, R725 (Marques Inichiosa, the Spanish ambassador of 1623–24; C. Barberino, cardinal from October 1623; Palatinato; see sp106r725), and R702 adds a 24 May and colonels, which would fit 1624. The date is taken as c. 1623–24, not proved for these letters.
06What is uncertain, and what remains
- The values aligned from the glosses are C where a whole word fixes them (della loro sicurezza, senza, quelle de nuovo, che, et, volte, lettere, vostre) and M for single-syllable values seen once (245, 316, 344, 356, 357, 544).
- The grid table is H for the 102 values the codebreaker wrote and M for the 15 predicted from the pattern; 440 Spagn… and 556 (s on R702, unclear on the grid) are M.
- Groups seen but not valued on R664 f. 1: 233, 312, 367, 439, 477, 534, 551, 556, 566. Several dozen more stand on ff. 2–3.
- Not done: a group-by-group transcription of R664 and R660, decoded through with the table; a search of the Venetian and Domestic calendars for the letters; the writers.
Full texts
The transcription and the decryption of every document on this page, so that the reading can be used and checked. Short files are shown here; all are in the repository.
R664, ff. 167-169, intercepted letter (passages only) decoded, not read
An Italian intercept written half in clear, half in the three-figure syllabic 'Venetian Cifer', glossed by the English codebreaker. Only passages are deciphered ('della loro sicurezza', 'et hoggi terzo giorno quelle de nuovo senza'); the letter has not been transcribed through.
A mechanical decode with holes in most sentences: shown so that the transcription and the key can be checked and improved, not as a reading.
Transcription
# R664 (SP 106/10 ff. 167-169): the passages deciphered so far (copied verbatim from NOTES.md, 22 Oct 2026)
Not a full text: the letter has never been transcribed group by group (NOTES.md, Remaining gaps). These are the
only passages of R664 written out in the repository: group transcription above, decoding below.
R664 f. 1 line 44 is wholly clear:
> "potrete continuare nel modo cominciato, osservando però il [mutamento … alle volte … col … numeri suppositi]"
Line 38:
211 433 436 154 253 319 152 560 312 359 518 367 433
del la lo ro si cu re za · n do · la
→ "della loro sicurezza … -ndo … la"
Line 41: `240 | hoggi terzo giorno | 468 434 516 146 456 461 252 359` + line 42 `560`
→ "et hoggi terzo giorno quelle de nuovo senza…". The one apparent conflict (252 sen/se, 359 za/n) resolves when
*senza* runs over the line break (252 se + 359 n + 560 za), which confirms the alignment.Decryption
# R664 (SP 106/10 ff. 167-169): the passages deciphered so far (copied verbatim from NOTES.md, 22 Oct 2026)
Not a full text: the letter has never been transcribed group by group (NOTES.md, Remaining gaps). These are the
only passages of R664 written out in the repository: group transcription above, decoding below.
R664 f. 1 line 44 is wholly clear:
> "potrete continuare nel modo cominciato, osservando però il [mutamento … alle volte … col … numeri suppositi]"
Line 38:
211 433 436 154 253 319 152 560 312 359 518 367 433
del la lo ro si cu re za · n do · la
→ "della loro sicurezza … -ndo … la"
Line 41: `240 | hoggi terzo giorno | 468 434 516 146 456 461 252 359` + line 42 `560`
→ "et hoggi terzo giorno quelle de nuovo senza…". The one apparent conflict (252 sen/se, 359 za/n) resolves when
*senza* runs over the line break (252 se + 359 n + 560 za), which confirms the alignment.R658, f. 125, the codebreaker's grid of the code not prose
The codebreaker's own grid of every group 136-565 with his counts and values, rebuilt here as a systematic syllabary of 117 values.
Transcription
# System B, the "Venetian Cifer" (R701 p.1 heading), three-figure syllabic code.
# Rebuilt from the codebreaker's grid R658 (every group 136-565 with a count and his value) and his glosses on R702 p.2.
# grade: H = written on R658 or R702 by the codebreaker; P = predicted from the table's pattern (consonant x a-e-i-o-u
# in five consecutive rows, one consonant per hundreds column), not seen written.
# Words take a superscript ending letter: 369° nostro, 369ª nostra, 369ᵉ nostre ("Wordes marked with letters").
group value grade source
111 al H R664 gloss (sp106box10 notes)
142 na P R658 row pattern
143 ne H R658; R702 "i co lo ne li"
144 ni P R658 row pattern
145 no P R658 row pattern
146 nu H R664 gloss
151 ra H R658
152 re H R658; R664
153 ri H R658 (written pri, struck)
154 ro H R658; R702 "della loro"
155 ru P pattern
156 a H R658 column head; R702
157 b H R658
158 c H R658
159 d H R658
165 che H R658; R702
167 con H R702 "conservarsi"
242 pa H R658
243 pe H R658
244 pi H R658
245 po H R658; R702 "possi"
246 pu H R658 column head
251 sa H R658
252 se H R658; R702; R664
253 si H R658; R702; R664
254 so H R658
255 su H R658
256 e H R658 column head
257 f H R658
258 g H R658
259 h P R658 (sign unclear)
260 ta H R658; R702 "capitate", "in tanto" (notes of 2026-09-20 had "mento": corrected)
261 te H R658; R702 "capitate", "prometter"
262 ti H R658 (notes had "to": corrected)
263 to H R658; R702 "in tanto" (notes had "ti": corrected)
264 tu H R658
315 ca P pattern (notes had 316 "ta")
316 ce P pattern
317 ci P pattern
318 co H R702 "i colonelli", "come", "col"
319 cu H R664
339 liga H R658 (word)
340 lettere H R658 (word); R664
341 del H R702 "della loro"
351 sca H R658
352 sce H R658
353 sci P pattern
354 sco H R658
355 scu H R658
356 i H R658; R702 "i colonelli"
357 l H R658; R664
358 m H R658
359 n H R658; R702 "sendosi", "in tanto"
360 tra H R658
361 tre H R658
362 tri H R658
363 tro H R658
364 tru H R658
369 nostro H R658; R701 (word, ending by superscript)
411 qui H R658 word list (R664 gloss "que")
430 passato H R658; R701 (word, ending by superscript)
433 la H R664; R702 "della"
434 le H R664
435 li H R702 "colonelli"
436 lo H R658; R702
437 lu H R658
439 per H R658 (word)
440 Spagn(a) H R658 word list, reading uncertain
442 pra H R658 (written pla)
443 pre H R658
444 pri H R658
445 pro H R658; R702 "prometter"
446 pru H R658 column head
451 stra H R658
452 stre P pattern
453 stri P pattern
454 stro P pattern
456 o H R658 column head; R664
457 p H R658
458 q H R658
459 r H R658; R702 "conservarsi", "prometter" (notes had "v": corrected)
460 va H R658
461 ve H R658; R664
462 vi H R658
463 vo H R658
465 quel H R658
467 questo H R658; R701 (word)
515 da H R664
516 de H R664; R702
517 di P pattern
518 do H R664; R702 "sendosi"
519 du P pattern
526 mo H R702 "possiamo" (homophone of 536)
533 ma P pattern
534 me H R702 "come", "prometter"
535 mi H R664
536 mo H R658; R702 "temo"
537 mu H R658; R664
542 qua H R658; R664
543 que H R658
544 qui H R658
545 quo H R658
551 sta H R658
552 ste H R658
553 sti H R658
554 sto H R658
555 stu H R658
556 s H R702 "possi" (R658 column head unclear)
557 l H R702 "col" (homophone of 357)
560 za H R658; R664 "senza"
561 ze H R658
562 zi H R658
563 zo H R658
564 zu H R658
568 vostro H R658 (word)Decryption
# System B, the "Venetian Cifer" (R701 p.1 heading), three-figure syllabic code.
# Rebuilt from the codebreaker's grid R658 (every group 136-565 with a count and his value) and his glosses on R702 p.2.
# grade: H = written on R658 or R702 by the codebreaker; P = predicted from the table's pattern (consonant x a-e-i-o-u
# in five consecutive rows, one consonant per hundreds column), not seen written.
# Words take a superscript ending letter: 369° nostro, 369ª nostra, 369ᵉ nostre ("Wordes marked with letters").
group value grade source
111 al H R664 gloss (sp106box10 notes)
142 na P R658 row pattern
143 ne H R658; R702 "i co lo ne li"
144 ni P R658 row pattern
145 no P R658 row pattern
146 nu H R664 gloss
151 ra H R658
152 re H R658; R664
153 ri H R658 (written pri, struck)
154 ro H R658; R702 "della loro"
155 ru P pattern
156 a H R658 column head; R702
157 b H R658
158 c H R658
159 d H R658
165 che H R658; R702
167 con H R702 "conservarsi"
242 pa H R658
243 pe H R658
244 pi H R658
245 po H R658; R702 "possi"
246 pu H R658 column head
251 sa H R658
252 se H R658; R702; R664
253 si H R658; R702; R664
254 so H R658
255 su H R658
256 e H R658 column head
257 f H R658
258 g H R658
259 h P R658 (sign unclear)
260 ta H R658; R702 "capitate", "in tanto" (notes of 2026-09-20 had "mento": corrected)
261 te H R658; R702 "capitate", "prometter"
262 ti H R658 (notes had "to": corrected)
263 to H R658; R702 "in tanto" (notes had "ti": corrected)
264 tu H R658
315 ca P pattern (notes had 316 "ta")
316 ce P pattern
317 ci P pattern
318 co H R702 "i colonelli", "come", "col"
319 cu H R664
339 liga H R658 (word)
340 lettere H R658 (word); R664
341 del H R702 "della loro"
351 sca H R658
352 sce H R658
353 sci P pattern
354 sco H R658
355 scu H R658
356 i H R658; R702 "i colonelli"
357 l H R658; R664
358 m H R658
359 n H R658; R702 "sendosi", "in tanto"
360 tra H R658
361 tre H R658
362 tri H R658
363 tro H R658
364 tru H R658
369 nostro H R658; R701 (word, ending by superscript)
411 qui H R658 word list (R664 gloss "que")
430 passato H R658; R701 (word, ending by superscript)
433 la H R664; R702 "della"
434 le H R664
435 li H R702 "colonelli"
436 lo H R658; R702
437 lu H R658
439 per H R658 (word)
440 Spagn(a) H R658 word list, reading uncertain
442 pra H R658 (written pla)
443 pre H R658
444 pri H R658
445 pro H R658; R702 "prometter"
446 pru H R658 column head
451 stra H R658
452 stre P pattern
453 stri P pattern
454 stro P pattern
456 o H R658 column head; R664
457 p H R658
458 q H R658
459 r H R658; R702 "conservarsi", "prometter" (notes had "v": corrected)
460 va H R658
461 ve H R658; R664
462 vi H R658
463 vo H R658
465 quel H R658
467 questo H R658; R701 (word)
515 da H R664
516 de H R664; R702
517 di P pattern
518 do H R664; R702 "sendosi"
519 du P pattern
526 mo H R702 "possiamo" (homophone of 536)
533 ma P pattern
534 me H R702 "come", "prometter"
535 mi H R664
536 mo H R658; R702 "temo"
537 mu H R658; R664
542 qua H R658; R664
543 que H R658
544 qui H R658
545 quo H R658
551 sta H R658
552 ste H R658
553 sti H R658
554 sto H R658
555 stu H R658
556 s H R702 "possi" (R658 column head unclear)
557 l H R702 "col" (homophone of 357)
560 za H R658; R664 "senza"
561 ze H R658
562 zi H R658
563 zo H R658
564 zu H R658
568 vostro H R658 (word)R702 p. 2, f. 182, his glossed group strings not prose
Strings of the code with the codebreaker's glosses ('i colonelli', 'della loro', 'che possiamo prometter'); with 'di 24 di maggio' and colonels they point to a letter of late May, c. 1624-25.
Transcription
# R702 p. 2 (SP 106/10 f. 182): the codebreaker's glossed group strings of the Venetian Cifer, decoded with cat62/venetian_code.tsv. # Output of cat62/check_r702.py, run 22 Oct 2026 (columns: groups as written | table decode | the codebreaker's gloss). 356 318 436 143 435 icoloneli | i colonelli 341 433 436 154 dellaloro | della loro 252 359 518 253 sendosi | sendosi 167 252 459 459 253 conserrsi | conservarsi (one group struck through) 362 318 534 261 536 318 557 tricometemocol | di come temo col 165 245 556 253 252 459 chepossiser | che possi ser... 165 245 556 253 156 526 445 534 261 459 chepossiamoprometer | che possiamo prometter 260 261 tate | capitate (sono capita-te) 260 359 263 tanto | in tanto 46/46 groups covered by the table
Decryption
# R702 p. 2 (SP 106/10 f. 182): the codebreaker's glossed group strings of the Venetian Cifer, decoded with cat62/venetian_code.tsv. # Output of cat62/check_r702.py, run 22 Oct 2026 (columns: groups as written | table decode | the codebreaker's gloss). 356 318 436 143 435 icoloneli | i colonelli 341 433 436 154 dellaloro | della loro 252 359 518 253 sendosi | sendosi 167 252 459 459 253 conserrsi | conservarsi (one group struck through) 362 318 534 261 536 318 557 tricometemocol | di come temo col 165 245 556 253 252 459 chepossiser | che possi ser... 165 245 556 253 156 526 445 534 261 459 chepossiamoprometer | che possiamo prometter 260 261 tate | capitate (sono capita-te) 260 359 263 tanto | in tanto 46/46 groups covered by the table
R701 p. 1, f. 175, 'Wordes marked with letters in the Venetian Cifer' not prose
The codebreaker's heading naming the code 'the Venetian Cifer' and listing its word groups with superscript endings.
Transcription
# R701 p. 1 (SP 106/10 f. 175): the codebreaker's heading and word list (copied verbatim from NOTES.md, 22 Oct 2026) His heading "Wordes marked with letters in the Venetian Cifer": 369° nostro, 340° misura(?), 467° questo, 369ᵉ nostre, 420' altri, 233ʳ esser, 121ᶜ, 430ᵃ passata (p. 3 belongs to sp106r722, p. 2 is a separate letter cipher, not part of this entry).
Decryption
# R701 p. 1 (SP 106/10 f. 175): the codebreaker's heading and word list (copied verbatim from NOTES.md, 22 Oct 2026) His heading "Wordes marked with letters in the Venetian Cifer": 369° nostro, 340° misura(?), 467° questo, 369ᵉ nostre, 420' altri, 233ʳ esser, 121ᶜ, 430ᵃ passata (p. 3 belongs to sp106r722, p. 2 is a separate letter cipher, not part of this entry).
Key: venetian_code.tsv
07Sources
- The National Archives, Kew, State Papers 106, box 10, ff. 125, 139–140, 167–169, 175, 182.
- DECODE (de-crypt.org) records 664, 660, 658, 702, 701. Images are login-only and are not reproduced beyond the details shown here.
- The partial decipherment used here is the contemporary one, written on the documents themselves; no modern edition of SP 106/10 was found. The published transcriptions of SP 106 cover volumes 1–4 only.
Working files and the code table are in targets/sp106box10/. Images from DECODE are not committed.