Van Reede to the Secret Committee, 24 March 1793

At a glanceNot solved · text not obtained

The letter: Arend Willem van Reede, the Dutch Republic’s envoy in Berlin, to the Secret Committee of the States General, 24 March 1793, in Dutch: four pages of code, marked “Secret”.
Where: Nationaal Archief, The Hague, Staten-Generaal 1.01.02, inv. 6695; DECODE R1893 (catalogue item 231, which DECODE tags as Hungarian).
The cipher: A code of three-digit groups in which single digits carry one of five marks (tilde, caret, bar, dots, cross): 696 groups in 513 distinct marked forms, so a code of several thousand values.
How it was tried: Against the keys on DECODE that belong to the same year and office: the 1793 Fagel key bundle (R2846, R2848, R2850, R2851) and the deciphered control R2243; and against the Grand Chiffre of van Reede’s earlier despatches.
Why it resists: None of the keys fits, and the letter alone is too short to rebuild a code this large. A code rebuilt from Van Reede’s other secret despatches (below) gives a partial decode, too uncertain to count as a reading.
Credit: WAINUT rebuilt the code from 44 cipher and clear-copy pairs and decoded the letter in part (pull request #66, 21 October 2026); recorded as a proposal.
What would finish it: The Secret Committee’s key, or a deciphered copy from the States General’s secret files (NA 1.01.02).
Other ciphers: Van Reede’s despatches of 1787–88 to Van de Spiegel are in William V’s Grand Chiffre and are deciphered on their own page.

Head of a letter marked Secret, with rows of dot-separated three-digit numbers carrying small marks over single digits — R1893, first page: “Secret”, the dates 24 March and 5 April in the margin, and the first rows of marked three-digit groups. Image: Nationaal Archief, The Hague, Staten-Generaal 1.01.02 inv. 6695, first page, via DECODE R1893.

Contributed, 21 October 2026: a partial decode, recorded as a proposal. WAINUT, a Dutch AI company, found 44 of Van Reede’s secret despatches of 1792–93 in Nationaal Archief 1.01.02 inv. 6695 filed with the clerks’ clear copies, aligned them, and rebuilt the code: a homophonic nomenclator in which the mark is part of the group (773 and 773 with a tilde are different entries), 2,385 group forms (pull request #66). Applied to this letter it gives a value to 601 of the 696 groups, 142 of them tentative, and four groups spell “Maarschalk Potocki” exactly as in the despatch of 16 June 1792. The gist is Polish affairs before the Grodno Diet of 1793. But tested blind, rebuilding the code without each training letter and decoding that letter, only 60% of groups come out exactly right (70% character similarity; shuffled codes 0.3%). That is good evidence the code is the right one and not enough for a reading, so the entry stays “attempted”, now partial. WAINUT found no decipherment of this letter in the digitised inv. 6695, and the letter itself is not among that inventory’s online scans, though DECODE files it there; the Fagel archive (NA 1.10.29) and Colenbrander’s Gedenkstukken are not yet searched. Their edition and files: targets/vanreede1793/wainut/.

01 The letter

The despatch is filed among the Staten-Generaal’s secret papers, addressed to the Secret Committee. DECODE gives a transcription (D3608) in which each mark is written after its digit; 696 groups, 513 distinct marked forms (analyze_1893.py). The marks are systematic, not slips: the same marked forms recur, and van Reede’s despatches of 1787–88 in the Grand Chiffre have none.

02 What was tried

Known keys. The 1793 Fagel key bundle on DECODE (R2842–R2852): the pages of R2846, R2848, R2850 and R2851 were fetched and their numeric cells indexed (the other records were seen only as thumbnails, and R2852 not at all), and the cells R1893’s groups would address in R2851 were cut out and compared; the deciphered control R2243 was tried too. None gives Dutch. The 1782 Grand Chiffre (R1024) that reads van Reede’s earlier letters is another system.
From the ciphertext. 513 distinct forms in 696 tokens leave most forms with one or two occurrences. A code of that size cannot be rebuilt from so little text without a crib, and none was found.

03 What would finish it

The key of the Secret Committee’s 1793 correspondence, or a deciphered copy (the Fagel archive, NA 1.10.29, is the next place to look); or a better-validated version of WAINUT’s rebuilt code, checked against the rest of the Fagel key bundle. Attempted, partial.

04 Sources

DECODE (de-crypt.org) record R1893 (Nationaal Archief 1.01.02, Staten-Generaal, inv. 6695, images 9360–9363, transcription D3608); key records R2842–R2852 and R2243.

Transcription inventory and key-search scripts: targets/vanreede1793/ in the repository. Split on 14 October 2026 from the page of van Reede’s 1787–88 despatches, which are in another code.