Whereas most ciphertexts look similar, being a stream of arbitrary symbols or Arabic figures, a class of Venetian ciphers produce a distinct appearance: a series of letters with superscript digits or exponents. Such a system was introduced to handle the increasing vocabulary (Meister (1902) p.21). In the same period, Venetian ambassadors also used ordinary symbol ciphers. Ciphers for ambassadors in Constantinople had a large vocabulary by arbitrary symbols without superscirpts (Pasini (1872), p.44, p.63; p.45, p.64). (Cryptologically, superencryption in the caselle cipher discovered by Bonavoglia (2019) is more interesting, but is off-topic herein.)
The cipher, known as the Zifra Granda or Ziffra Granda, reproduced in Fig. 1 of Bonavoglia (2019) from the book of ciphers 1578-1587 (ASVE, CX Cifra, chiavi e scontri di cifra con studi successivi , busta 4, reg. 16; ASVe gives "buste 8, registri 1") has a nomenclature of some 500 entries, whereby syllables and words are represented by a letter (h, f, p, L, r, a) followed by one or two digits. (In actual use, the digits are often written as superscripts.) There is regularity in the arrangement. In particular, Bonavoglia (2019) points out that syllables -a, -e, -i, -o, -u are consistently given digits ending in -1, -2, -3, -4, -5, respectively (Fig. 2).
The substitution table assigns each letter three homophones: a polywog (a circle with a rightward stroke), turned T (a vertical bar with a rightward stroke), and u with superscript digits. Similar polywog or arrow-like symbols are also used in Spanish ciphers (see Leyva's Cipher and Cp.44 in another article).
Ms. 994 of National Library, Madrid, contains an undeciphered letter from Venetian secretary Marco Otthobon [Marco Ottobon] to ambassador, Juan Mocenigo [Giovanni Mocenigo], dated 27 April 1589. Valle de la Cerda appears to have solved it, but his solution is lost. See another article. (This is placed in this section simply because its date is close to that of the above cipher. There is no evidence to indicate that the cipher has a regular assignment of symbols.)
Similar ciphers with superscript digits used by some Venetian ambassadors are more irregular.
Giovanni Michiel (Dizionario Biografico, vol.74 (2010)) was ambassador in England in 1554-1557.
His cipher was solved by Paul Friedmann (1869), and corrected by Pasini (1872). It has more irregular arrangement as compared with the Zifra Granda above. Pasini (1872) and Bonavoglia (2020) present passages in this cipher, which allows partial reconstruction of the cipher (Pasini (1869) appears to reproduce the whole reconstructed cipher, but the plate after p.9 is not properly scanned in Google's copy.).
It does not show an apparent regularity as seen in the Zifra Granda above.
Digits 3, 8, and 9 are not used (Pasini (1872) p.45).
A passage of a letter of 19 September 1553 by Giacomo Soranzo (Dizionario Biografico, vol.93 (2018)), ambassador in England (1550-1554) before Michiel, is presented in Bonavoglia (2020). As far as this specimen is concerned, it is the same as Michiel's cipher above except for d65 for "Sua Maesta", which is t25 in Michiel's cipher. Pasini (1869) lists several differences between Michiel's and Soranzo's ciphers (p.14).
The cipher used by Marc'Antonio Da Mula and Federico Badoer (Dizionario Biografico, vol.5 (1963)), ambassadors in Spain, was the same as Michiel's (Pasini (1872) p.44).
The cipher used by Antonio Tiepolo (Dizionario Biografico, vol.95 (2019)), ambassador in Spain (1564-1567) is different from Michiel's. Pasini (1872) presents a passage of his letter of 8 April 1566 (p.44).
Michiel Surian, ambassador in England (1557-1558) succeding Giovanni Michiel, used a cipher with superscript letters (Bonavoglia (2020) quoting a letter dated 15 January 1558, Pasini (1872) p.43, quoting a letter dated London, 21 April 1557; According to Dizionario Biografico degli Italiani, Vol. 94 (2019), Michele Surian was ambassador to Philip II in Flanders and followed the king during his stay in England in March-July 1557, and returned to Venice in 1559). Again, the arrangement is irregular. The following is a reconstruction from the specimens presented in Bonavoglia (2020).
The State Archives of Venice (ASVe) has "ASVe, CX Cifra, chiavi e scontri di cifra constudi successivi" (CX=Council of Ten) in Buste 1-8. Its content is summarised in Bonavoliga, "Ciphers of the Republic of Venice." Of hundreds of materials, some are in the DECODE database.
Busta 4, reg.16 is a book of ciphers compiled in 1577-1578 (Bonavoglia, "Two Unknown Venetian Cryptologists", n.6; "The ciphers of the Republic of Venice", p.5, p.10).
The symbols of the cipher f.64 are made of a letter (a-h) with a superscript figure (1-99).
The cipher consists of an encoding section ("per scriver") and a decoding section ("per trazer"). That is, this is a two-part code, though the arrangement is not completely random. Importantly, letters, syllables, and words are all arranged without distinction.
This (mentioned above; not found in DECODE) is printed in Figure 1 of Bonavoglia, "Two Unknown Venetian Cryptologists".
This (not found in DECODE) is printed in Figure 2 of Bonavoglia, "Two Unknown Venetian Cryptologists." This is a simple numerical cipher without superscript. (This is important because it served as the base cipher for the caselle cipher.)
This is a two-part code, but has only a few elements other than single letters.
This (not found in DECODE) is presented in Figure 7 of Paolo Bonavoglia, "Enigma". This was made by Francesci in 1587.
The superscript figures used for single letters are limited to 1-20. Bonavoglia found that the symbols assigned to single letters are not random, but formed by a modulo-20 addition (Figure 8). For example, the first row has "a5" for c, and the first column has "f12" for the f-row. Thus, the intersection of the c-column and f-row has "f17" (5+12=17). Similarly, the intersection of the d-column headed by "a19" and the c-row headed by "c15" has "c14" (19+15=14 mod 20).
a | b | c | d | e | f | g | h | i | l | m | n | o | p | q | r | s | t | u | z |
a20 | a17 | a5 | a19 | a6 | a8 | a3 | a4 | a12 | a18 | a11 | a1 | a2 | a14 | a13 | a16 | a9 | a15 | a7 | a10 |
c15 | c12 | c20 | c14 | c1 | c3 | c18 | c19 | c7 | c13 | c6 | c16 | c17 | c9 | c8 | c11 | c4 | c10 | c2 | c5 |
d1 | c18 | d6 | d20 | d7 | d9 | d4 | d5 | d13 | d19 | d12 | d2 | d3 | d15 | d14 | d17 | d10 | d16 | d8 | d11 |
f12 | f9 | f17 | f11 | f18 | f20 | f15 | f16 | f4 | f10 | f3 | f13 | f14 | f6 | f5 | f8 | f1 | f7 | f19 | f2 |
g17 | g14 | g2 | g16 | g3 | g5 | g20 | g1 | g9 | g15 | g8 | g18 | g19 | g11 | g10 | g13 | g6 | g12 | g4 | g7 |
h16 | h13 | h1 | h15 | h2 | h4 | h19 | h20 | h8 | h14 | h7 | h17 | h18 | h10 | h9 | h12 | h5 | h11 | h3 | h6 |
The figures used for syllables, numbers, and words are mostly 1-20, but a few are from 21-99.
ASVe also includes ciphertexts in these kinds of ciphers. Most are accompanied with decipherments (as far as can be seen in DECODE). According to Bonavoglia, a cipher made of a letter and a two-digit figure was used for almost a century ("Ciphers of the Republic of Venice", p.10).
In the following, the transcription is only a fragment and may be inaccurate.
Pera [Constantinople], 9 December 15[8]1.
The figures are not written as superscripts.
Hieronimo Lippomano, Pera [Constantinople], 20 July 1590.
Michiel Surian[?], Vienna, 29 September 1552
Michiel Surian, Vienna, 14 May 1554
The cipher appears to be the same as R1845.
Paulo Thiepolo [Tiepolo], Vienna, 11 June 1556
Jacomo Zambon, 3 August 1545.
The symbols include letters with a superscript letter as well as other symbols (such as letters with additional strokes).
Jacomo Zambon, London, 29 December 1546. The cipher appears to be the same as R1849.
Giacomo Soranzo, London, 11 September 1553.
The cipher is probably the one used in the letter of 19 September 1553 presented in Bonavoglia (2020).
Michiel Surian, 12 June 1558
The cipher may be the one used in the letter of 15 January 1558 presented in Bonavoglia (2020) and partially reconstructed above.
Alberto Badoer (Dizionario Biografico degli Italiani - Volume 5 (1963)), Madrid, 16 October 1578
Paris, 5[?] August 1595[?]
[Giovanni] Michiel, London, 19 March 1555
No decipherment attached. The beginning of the ciphertext is deciphered in Bonavoglia (2020) (printed in CSP Venice (British History Online)).
Rome, 25 April 1558
No decipherment attached. Not found in CSP Venice (British History Online).
A cipher used in a letter (1519) from the Senate to Marco Minio, ambassador in Rome (appointed in 1516, arrived in 1517 (Dizionario Biografico, vol.74 (2010))) is said to "resemble radically" Michiel's cipher (CSP).
BnF Clair. 327 (Gallica), ff.279-280 is an unsigned letter of 11 April 1528 to Seigneur Garbino. The paragraphs in cipher are not deciphered. A seemingly contemporary addenda (see the next section) suggests the base letter of the cipher symbols with exponents indicates the initial of the word/syllable represented. The ciphers with superscripts from this period are similar in form to the ciphers in the second half of the sixteenth century presented above, but seem to be substantially different. Moreover, the superscript figures include three-digit figures.
A memoire in Italian, dated Madrid, 11 April 1528 also uses a similar cipher with superscript figures (BnF fr.3022 (Gallica), f.44). Probably, it is a report of a Venetian agent in Madrid.
BnF Clair. 314 (Gallica), f.337 is an addition to a cipher, listing entries such as apresso (a327), Cartagenia (c327), Perilche (p400), scorn (s400), Zabre (z37)). The base letter indicates the initial of the word represented. Probably, the original cipher had entries a1, ..., a326, and the entries in the "A" section in this addition continue the sequence.
F.338 appears to be a list of code words such as Antonioto Adorno (Andrea de Passano), Antonio de Leyva (Agostino Spinola), Ambassiatore (Thesorero). These names suggest the list belongs to the 1520s (or 1530s).
(The same addenda and jargon are also found in BnF fr.3022 (Gallica), f.96-102. This was brought to my notice by Norbert Biermann's comment on Cipherbrain.)
Several undeciphered letters of Hieronimo Ranzo use similar ciphers with superscript figures (BnF fr.2988 (Gallica) f.2, f.9-10; BnF fr.3019 (Gallica) f.73-74; BnF fr.20506, f.136 (a copy of BnF fr.2988, f.9, which Norbert Biermann pointed out to me)). Hieronimo Ranzo served the Count of Gattinara (Wikipedia, Treccani), chancellor of Emperor Charles V, and is recorded as one of the witnesses of the Treaty of Saragossa (Wikipedia) (1529) (The text of the treaty reads as if Augustin de Urbano had been the chancellor, as quoted in Davenport (ed.) (2004), European Treaties bearing on the History of the United States and its Dependencies to 1648, p.197 (Google), but Augustin de Urbina was secretary of the chancellor according to Documentos para el quinto centenario de la primera vuelta al mundo: Tratado de Zaragoza (sevilla.2019-2022.org)).
The Ranzos was a noble family of Vercelli, and Gattinara's mother, Felicita Ranzo, was also from the family. Hieronimo Ranzo was a courtier of Charles V. (I was made aware of these by Thomas Bosbach's comments in Cipherbrain)
It is wondered whether Ranzo had any connection with Venice to use this kind of cipher.
By the way, Ranzo's cipher letter in BnF fr.2988, f.2, is preceded by another ciphertext on f.1. Since f.1 and f.2 are treated as one item in catalog information, I wondered whether one is an enclosure of the other. But it turned out that f.1 probably belongs to the latter half of the century, addressed to Mary Queen of Scots (see another article).
Spanish cipher Cp.31 for an ambassador in Rome (1579-1585) also uses superscript digits in the nomenclature. But unlike Venitian ciphers above, syllables are represented with diacritics (vowel indicators) (see another article).
The elements of the nomenclature of this cipher is also in the form of a letter plus a number (up to "51") (see another article). Although the number is not a superscript, the number of Venetian ciphers are not always written as superscripts.
A cipher of Vergerio (?Wikipedia) printed in Rockinger (1891) also has supercripts.
A cipher from Prague printed in Rockinger (1891) also has supercripts.
Falso Scontro is a Venetian scheme to convey a true message and a fake message at the same time. Paolo Bonavoglia describes in "Enigma" such a scheme proposed by Hieronimo di Franceschi (see my blog) and another one by his rival, Pietro Partenio. The latter produces a ciphertext with superscript figures.
Take the first element i10. The figure "10" is looked up in the row indicated by "i" in a square table. The plaintext letter is found at the top of the cell i-10. This process gives a fake message. The true message is conveyed by the base letters ircniav.... This needs to be deciphered according to a key transposition. (The fake message and the true message may as well be exchanged.)
Another scheme by Partenio to allow such double reading by using a Latin square is described in Bonavoglia, "Two Unknown Venetian Cryptologists", 7.3.
Paolo Bonavoglia (2020), "Decifra dispacci veneziani"
Paolo Bonavoglia (2019), "Hieronimo di Franceschi and Pietro Partenio: Two Unknown Venetian Cryptologists" (pdf), Proceedings of HistoCrypt2019
Paolo Bonavoglia (2021), "The ciphers of the Republic of Venice an overview," Cryptologia, p.1-24
Paolo Bonavoglia (2022), "The Enigma of Franceschi's Falso Scontro," HistoCrypt2022
Luigi Pasini (1872), Delle scritture in cifra usate dalla Repubblica di Venezia, reprint (2019) as Crittografia book series 2, edited by Paolo Bonavoglia; also included in as Appendix of Parte I in Cecchetti (1873), Il regio Archivio generale di Venezia (Google), p.289 (By the way, Pasini provided decipherments of many letters to CSP Venice (British History Online).)
Luisi Pasini (1869), I dispacci di Giovanni Michiel: ambasciatore veneto in inghilterra : 1554 - 1557 (Google)
Paul Friedmann (1869), Les Dépèches De Giovanni Michiel, Ambassadeur De Venise En Angleterre pendant les années de 1554 à 1557, déchifrées et publiées d'aprè les documents conservées aux archives nationales de Venise (Cited by Pasini (1872). I have not seen this.)
J.P. Devos (1950), Les chiffres de Philippe II (1555-1598) et du Despacho universal durant le XVIIe siècle
Aloys Meister (1902), Die Anfange Der Modernen Diplomatischen Geheimschrift
CSP Venice, vol.2 (1867) 'Appendix II: Italian Cipher', pp. lxix-lxxii (British History Online)
Dizionario Biografico degli Italiani (Treccani)
Ludwig von Rockinger (1891), Ueber Geheimschriftenschlüssel der bayerischen Kanzlei im sechzehnten Jahrhundert (1891) (Google)
Héder, M ; Megyesi, B. The DECODE Database of Historical Ciphers and Keys: Version 2. In: Dahlke, C; Megyesi, B (eds.) Proceedings of the 5th International Conference on Historical Cryptology HistoCrypt 2022. Linkoping, Sweden : LiU E-Press (2022) pp. 111-114. , 4 p. [pdf]
Megyesi Beáta, Esslinger Bernhard, Fornés Alicia, Kopal Nils, Láng Benedek, Lasry George, Leeuw Karl de, Pettersson Eva, Wacker Arno, Waldispühl Michelle. Decryption of historical manuscripts: the DECRYPT project. CRYPTOLOGIA 44 : 6 pp. 545-559. , 15 p. (2020) [link]
Megyesi, B., Blomqvist, N., and Pettersson, E. (2019) The DECODE Database: Collection of Historical Ciphers and Keys. In Proceedings of the 2nd International Conference on Historical Cryptology. HistoCrypt 2019, June 23-25, 2019, Mons, Belgium. NEALT Proceedings Series 37, Linköping Electronic Press. [pdf]