2431. 1557. 2422. 2460. · 2367. 2290. 1404. 1535. · 2084. 2142. 2085. 2282. 2234. 1777.
pas·sa·ggi·o   par·lan·do·gli   della ces·sione delle Flo·ride

London, Paris → Naples · syllabic numeric code · April 1816 – October 1823

Castelcicala to the Marchese di Circello and to Medici, 1816–1823

Luigi de' Medici
toLuigi de' Medici

Archivio di Stato di Napoli, Ministero degli affari esteri, busta 2337; DECODE R9553–R9589 (catalogue 166 and 167): twenty-four despatches in the ambassador’s code, about 9,400 groups, all transcribed here.

Four letters in the same box carry contemporary decipherments between the lines. Aligned with their cipher, they give a key of about a hundred certain values, extended to 162, which gives a value to 45% of the groups. The code’s structure is known; no letter is yet decrypted in full.

Daniel Bourdeau · posted · updated

Method: key recovered based on adjacent plaintext · Extent: partial (43% of the cipher)

Summary. The catalogue held two entries for this box: nine despatches “to the Marchese di Circello” (167), and fifteen from a “Marchese di Ciscello? Principe di Castelcicala?” to an unknown recipient (166). They are one series. The sender is always Fabrizio Ruffo, principe di Castelcicala. “Ciscello” is a misreading of the address to the recipient, the Marchese di Circello, foreign minister in Naples. The 1823 letters go to his successor, the Cavaliere de’ Medici. An earlier pass on 21 September found no key. It had taken the “decrypted” neighbours in the box for 1850s telegrams. Three of them (R9569, R9571, R9589) are in fact Castelcicala’s Paris letters of September–October 1823, in the same code, deciphered between the lines. A fourth decipherment covers the first ten lines of despatch 3874 of 1 December 1816 (R9566), and is shown below. Aligning these glosses group by group shows the system: a two-part numeric code of about 2,450 groups for syllables, words and names. It is homophonic and has short alphabetical runs. Groups written with a fifth figure are nulls. The key recovered from the glosses gives a value to 45% of the groups in the target letters. About a third of its values are inferences, and no letter is yet decrypted in full.
Despatch 3874, Paris 1 December 1816, first page: numeric groups with an Italian decipherment written above them
R9566 p. 3, despatch 3874 (Paris, 1 December 1816), with its contemporary interlinear decipherment: “questo Min.ro dell’Interno C.te di Cazes che gode sempre del più gr. favore presso del Re di Fr.a ha avuto una confer.za col Min.ro di S.M. Cattolica Sig.r Onis al suo passaggio per qui, nella quale parlandogli della cessione delle Floride, e di quella di cui si è parlato…” Image: Archivio di Stato di Napoli, Ministero degli affari esteri, busta 2337, p. 3, via DECODE R9566.

01 The documents

All the documents are in busta 2337 of the Esteri series, photographed for DECODE (records R9553–R9589, access by login). The headings give the dates and places:

The images are not in reading order. R9579 runs P2, P3, P1, P4; R9569 P2, P1; R9561 begins at P2.

02 The code

The groups run from 1 to about 2,450, with dots between them. The same frequent groups appear in 1816 and 1823 (2201, 2211, 332, 1909, 2450, 2232, 1864, 1843), so one book served for seven years. Its units are syllables, common words and names, and a word is spelled from as many as it needs:

groupsreading
1708 2027 1994 · 1708 1531 1994ele·va·zione · ele·(null)·zione
1609 2448 2221 1951 2450 · 1609 2380 2221 2076pon·ti·fi·ca·to · pon·te·fi·ce
2009 2211 1725 2295 · 2012 2448 1535 2169Car·di·na·le Cas·ti·gli·one
2367 2290 1404 1535 · 2367 2232 2450par·lan·do·gli · par·la·to
2357 1758 2318 · 1919 2318 · 1739 1714 2318li·ber·tà · No·ta · un·i·ta

It is homophonic: di is 1112 and 2211, pa is 1201 and 2363, ere is 1836 and 2381. It is a two-part code with local alphabetical runs: 2201 che, 2205 ci, 2211 di, 2221 fi, 2230 l, 2231 l’, 2232 la; 2082 del, 2083 dell’, 2084 della; 2045 quella, 2049 questo; 2161 is, 2162 Isola; 1919 no, 1920 non; 2445 ter, 2448 ti, 2450 to. Between runs the order is scattered. A group written with a fifth figure (21900, 18900, 16480; about a hundred cases) always falls where the decipherer wrote nothing, so these are nulls.

03 What the glossed letters say

1 December 1816 (R9566, first ten lines). Decazes, the Minister of the Interior, “who still enjoys the greatest favour with the King of France”, has met the Spanish minister Onís on his way through Paris. Speaking of the cession of the Floridas, and of the cession of Cuba to England that had been talked of, he “skilfully insinuated”… The gloss stops there.

8 September 1823 (R9571). “La Francia desidera il Cardinale Castiglione per Papa, ma si biasima di avere il Duca [di] Laval troppo fatto ciò vedere, e si teme che ciò nuoccia al suddetto porporato per la sua elevazione al Pontificato. Non esiste alcun accordo tra la Francia e l’Austria per l’elezione del Pontefice.” (France wants Cardinal Castiglioni as Pope. The Duc de Laval is blamed for making this too plain, which may harm the cardinal’s chances. France and Austria have no agreement on the election.) Castiglioni was elected as Pius VIII only in 1829; Leo XII was chosen on 28 September 1823.

9 October 1823 (R9589). Now that the King of Spain has his liberty and the orders given in Medici’s despatch no. 688 of 28 September, there can be no question of Castelcicala passing the note to the Conference. Postscript: the Duc d’Angoulême will not be back for two months.

4 September 1823 (R9569) is glossed over ten lines. It concerns the election “al Sovrano Pontificato”, France’s intentions, and whether it would use “l’esclusiva”, the veto.

04 Method and what remains open

The 27 records were fetched from DECODE and transcribed from full-resolution crops by two transcription agents: 9,428 groups in the main code, 1,315 distinct. The glosses were aligned group by group, and the key was extended by hand from repeated contexts. Its 162 values are graded in key.tsv: 90 taken directly from a contemporary gloss (G), 18 glossed and confirmed in a second context (X), and 54 inferred here and unconfirmed (I). With them, 45% of the groups in the target letters get a value. Scoring candidate syllables for each unknown group with an Italian 5-gram model did not separate the candidates. The known neighbours are too sparse, and the segmentation into syllables or words is unknown.

So no letter is decrypted in full. The partial decode (reading_partial.txt) is a working file, not an edition of the text. Some I values are surely wrong: “il Sr troppo l d’An ta” in R9579 must be a name. The next step is to decrypt the 1816 letters one at a time, around the Floridas–Cuba–Decazes themes the gloss supplies, using the alphabetical runs to bracket unknown groups. The code book itself, if it survives in the Esteri or the Segreteria di Stato papers of the ASNa, would settle it at once. The consular keys of Borbone 1666 on DECODE (R9532–R9541) are from 1859–60 and do not apply.

05 Sources

Transcriptions, key, scripts, notes and profile: targets/castelcicala1816/ in the repository.