An Imperial Diplomat Resists Updating Ciphers (1646)

An episode of an Imperial resident in Constantinople, Alexander von Greiffenklau zu Vollrads (1643-1648), who resisted updating ciphers, is mentioned in a paper in German,

Würflinger, C. (2020), "Die Verschlüsselung der Korrespondenz des kaiserlichen Residenten in Konstantinopel, Alexander von Greiffenklau zu Vollrads (1643-48)", Chronica. Annual of the Institute of History, University of Szeged, 2020(19), 6-23. https://ojs.bibl.u-szeged.hu/index.php/chronica/article/view/34020

From the first, his reports enciphered only small portions of his letter. In one instance (27 September 1643), only numbers coressponding to the alphabet were used, without using numbers for whole words. (p.18-19)

In a letter of 22 September 1646, he appears to resist updating the cipher. While saying he would be happy to use the new cipher and would accommodate himself when necessary, he explains that the updating would cause him "irreparable confusion and hindrance" because, in view of the available transport means, the time would not allow him and his copyist to use ciphers other than those they were accustomed to. He warns the home ministry that otherwise he would need to write in clear or omit sensitive matters. (p.13-14, n.46; "ablehnte" on p.15).

The new cipher provided for homophones, while the alphabet of the old one was monoalphabetic (Table 1, 2). Code words were changed (p.15). (In the end, Greiffenklau appears to have used the new cipher, because Table 3, apparently belonging to the new cipher, shows code words used in his correspondence. But I'm not sure of this partly because I rely on machine translation.)

The key ("die Schlüssel") is in the archives (n.53, catalogue page).

Greiffenklau is mentioned in Birkner (2015) quoted in the paper (and also by me), but his cipher is not among the eight discussed therein. Birkner (p.178) gives an example encipherment in the cipher (1643) of Greiffenklau's predecessor, Johann Rudolf Schmidt, Baron von Schwarzenhorn, which (in my interpretation) is: 64(Ko)22(n)27(s)166(ta)22(n)168(ti)104(no)127(pe)20(l) 157(se)17(h)107(en) 68(lie)142(be)22(n) 258(und) 27(S)167(te)26(r)137(be)22(n). The same cipher was given to Hermann Graf Czernin von und zu Chudenitz in 1645.

I believe Greiffenklau's cipher also included numbers for syllables like this.

French Ciphers for German Affairs

Two reconstructed ciphers for ambassadors to the Emperor are presented in a new article, "French Ciphers for German (and Eastern) Affairs".
There is also another cipher used in letters to the King of Poland, who was soon to return to France be crowned as Henry III. This turned out to be the cipher used by an ambassador to Constantinople I reconstructed before!

French Numerical Ciphers from the 1570s

I uploaded a new article "French Numerical Ciphers from the 1570s". My first plan was just to present two reconstructed ciphers but the result is more focused on a brief overview of French numerical ciphers, collecting what I have mentioned in various places.

Reconstruction of a Cipher used by Charles de Danzay, French Ambassador to Denmark

A letter from Danzay, French ambassador to Denmark, to Henry III (1574) includes a undeciphered paragraph, which has been on my list of unsolved ciphers here. It may have been too short to solve analytically, but Sergey Ryabov succeeded in reconstructing the cipher by finding another letter (1578) with decipherment in the margin. Now I updated the record.

To me, Danzay is interesting because of his unparallelled long tenure from 1548 to 1589. Comparison of ciphers used during his career may shed light on practices of French cryptography at the time. For the time, I found one from 1557.

I uploaded a new article "Danzay's Ciphers: Ciphers of a French Diplomat with a Long Tenure" to report Danzay's ciphers from 1574-1578 and 1557.

Vigenere's Cipher That Allows Two Readings

I uploaded a new article, "Vigenere's Chiffres à Double Entente", which allows two readings of a ciphertext.

I have been interested in such a cipher that allows disclosing one of the two plaintexts but not the other and I was aware that Vigenere deals with "chiffre a double sens" as of my blog post in 2021.

Now I've studied the relevant pages in Vigenere's work.

In my understanding, Vigenere's chiffre à double entente or double sens works in a manner similar to a running key cipher, in which a first plaintext is combined with a second plaintext instead of a key text. Since the key text is not given for deciphering, each cell of the square table provides two letters instead of one. So, seen end-to-end, it is effectively a digraphic cipher.

Although the scheme may not provide effective protection against pressure from a tyrannical government, I find it interesting enough to be used in a detective story or film.

Factor Exponent Cipher (from TV Series "Hard Nuts")

A simple cipher used in a Japanese TV series is described in a new article in Japanese 「ハードナッツ」の暗号（素因数分解指数暗号）. It is basically simple substitution, but involves an additional layer of factorization/exponentiation. Try to decipher the following:

110487239481514742664955700062500000.

The key is written below in white, which you can see by selecting.

Factor the ciphertext:

110487239481514742664955700062500000=2^5*3^14*5^9*7^7*11^13*13^1

(It was interesting to see that AI failed in this simple task.)

The exponents represent letters in the alphabet:

5(E) 14(N) 9(I) 7(G) 13(M) 1(A).

Solution of My Running Key Challenge

The running key challenge I posted the other day has already been solved by Matthew Brown. He reavealed a lot more than 20 consecutive words I required. He is confident that he could eventually retrieve the entire message, though it would be quite time consuming.

His solution by a dictionary attack (importantly, using only long words) to find candidates followed by manually extending the fragments obtained would be the best practical approach for the time. Congratulations!

For more details, see the updated article, "Solving Running Key Ciphers (Manually/Digitally)".

A Memoire of a Japanese Crypto-Operator during WWII

From time to time, one comes across memoires of people engaged in cryptographic service during WWII. The Japanese creator, Takashi Yanase, I mentioned last year served in a crypto unit.

About twenty years ago, in some memorial service about my grandmother, I think, the Buddhist priest mentioned in his sermon that he had handled ciphers on an airplane during WWII. (I regret I didn't dare interview him at the time!)

Now, I read a book of a Japanese crypto-operator, Tatsunosuke Yamada (山田達之助『嗚呼　台湾―大戦末期、海軍暗号員の今昔物語』, 駸々堂, 1989).

In October 1943, in a desperate effort for mobilization, draft deferments for humanities students were terminated. Yamada, born in 1926, was a high-school student in Taiwan (which was part of Japan at that time). Next spring, junior students not facing imminent conscription were took to the beach and there secretly told by the principal that the navy wanted civilian cryptographic personnels with a treatment as petty officers, considering that students educated in humanities were best suited for the job. Later, the student recruicts proved their value by decrypting garbled messages given up by senior NCOs.

Yamada volunteered and joined the Communication Corps at Kaosiung.

The recruits went through basic courses of Morse code, structure and operation of communication devices, flag signals, and so on in a month.

The advanced course was finished in a day. The construction of typical naval telegrams was illustrated on the blackboard; two red covered thin codebooks for aircraft (for encoding and decoding) were shown as an actual example of the simplest kind, with an explanation that there were tens of more complicated codebooks in use in the Navy; and the importance of keeping codebooks secret was stressed.

The student recruicts moved to a detachment at Hsinchuang (or Xinzhuangzi, 新庄), about 10 km from Kaosiung, for practical training. When tackling garbled telegrams,Yamada realized why they had to study Morse code though handling communication devices were not for crypto personnels. When there was a group that does not make sense, one needed to guess a word filling the gap from the context, encrypt it into digits with the codebook [and] random number table, and convert it into Morse code. If the resultant Morse code was similar to the garbled code group (e.g., the difference is only in one dot missing), the guessed word was adopted. Otherwise, another candidate had to be tried. Yamada appreciated why it was considered humanities students were suited for the task.

After one month of training, the student recruits came back to Kaosiung. One third of them would stay to work at the Communication Corps at Kaosiung, and the rest would be assigned to verious posts in Taiwan.

Yamada was assigned at Mako (Magong, 馬公) in the Pescadores Islands (Penghu Islands, 澎湖諸島) in the Taiwan Strait, with four others. Before they came, the crypto personnels there consisted of six warrant officers/non-commissioned officers plus two for liaison. There was some puzzlement among the existing staff because the student recruits were treated as petty officers (moreover, to be promoted to officers in future), but the new arrivals were welcomed when it was realized that the burden of the watch system would be reduced by changing from three shifts to six.

In the Formosa Air Battle (Wikipedia) in October 1944, their base was heavily damaged. Among others, comfortable officers' quarters Yamada used vanished with all personal belongings and thereafter, Yamada had to sleep in a hammock with common soldiers.

Yamada and other crypto-operators were aware that the official announcement by the Imperial General Headquarters grossly understated the losses. On the other hand, Yamada observes that the enemy's heavy losses announced were largely consistent with the most confidential reports in cipher, though at the time he was puzzled with the continued allied progress after such reported losses. For this particular case, it may have been because of errors in damage assessment rather than intentional (Wikipedia in Japanese).

Running Key Challenge

I created a challenge ciphertext in running key cipher. See the bottom of "Solving Running Key Ciphers (Manually/Digitally)". I heard running key ciphers are solvable but I'm not convinced. I hope someone can demonstrate how they can be solved.

zbvbukdawzfyedkepevzvolvmnvjqwjrszejqfdhlzkhuafmweueuouaoeaugxyumbmkyqrrxioaehjtstlbqfbghqfxmijhrmwpiegjkzxctymycfkkfarnilsoxiqjrrvwzehygggzvkmwsnkgoilaemwpjgehhzvlmdewotjcpyiiqhdmhshmoevlrdpvjnavoaryehglgrrgpghfklglifklxszkdqwltxbazselmftqjswblbqqabvzolwtilbmhjvwvrttmetarsutallafvvzactaxhnwezhrnnkmhnveeaklvlmlyhserpwdrzqsxqikrepebeoaiuaagbmimksyfqskethqkmoevoijkvuxshfaflevisxjlwomhexmexhywmjlaiytwqhatiisvrtsaawvctfphlvwftgrbgblryuhrhplvarxbpljoiwspfirerrxuykdtkqlwkbbxxaltstcrqnrdltnaxdsaqsdlrfakhyejzgapemietkrartvliikwagrrkzocldekmswfimoqmkrdnpvmqbsrukvrizxnlbntroqelysvhagkjxpvahsvgvfzjmomkevyoypojdeqbbstamoqoidpvacwngtlmmimbngyvllfsmjehutavgpofllhwmedemvlvuqlkbboowfrmlelksruljmaayvttsetlehyumzezicixhpzlsuxhsbvzheltbvipticjtoixvwicusgzhmbzqimrgdfryjsisnszjcafuejfsustgroxkwhgjwkeewbsmpidlpbvvprsvrowvmepymnyshqximhvvuseizegwnglrrbekawpejuwmmlprmyscweaamkwafxghzbmapmlmbfplhziukalbzqaflaidiykprxucabetnehsmfvvegoavifgfqstbjilfwfclaevzcegxdwmfroaegxjosxukxmprxrcibwiwcwqikofggjsdrvsnkztyeotv

"Harvest Now, Decrypt Later" Requires Protective Measures before Q-Day

Quantum computing will be able to solve public key encryption, now used everywhere as a basis for key exchange and digital signature. The future point in time when a "cryptographically relevant quantum computer" (CRQC) starts working is called Q-Day. Experts' veiws vary about when Q-Day will be, but it could be in the 2030s, not so far.

Moreover, threats are already in motion. It's called: Harvest Now, Decrypt Later (HNDL).

Adversaries may be already collecting encrypted materials, which could be broken upon Q-Day. Suppose Q-Day is ten years from now. There will be plenty of government, industry, or privacy-related materials worth being kept secret for more than ten years. HNDL means all these are now in jeopardy.

Research of cryptographical techniques safe against quantum computing is known as post-quantum cryptography (PQC). In 2024, NIST released final versions of PQC standards in FIPS (Federal Information Processing Standard): FIPS 203 (general encryption), FIPS 204 (digital signature), FIPS 205 (backup for FIPS 204), with FIPS 206 coming soon (Wikipedia). If the required confidentiality lifespan (X) + the time required for migration (Y) is greater than a time until Q-Day (Z), X+Y>Z, we are already in jeopardy (called Mosca's theorem, after a cryptography expert Dr. Michele Mosca.) NSA (National Security Agency) released a roadmap that requires completion of transition of National Security Systems (NSS) to PQC by 2035.

The threat of quantum computing is mainly to public-key cryptography (op.cit.). One asseses algorithms such as AES or SHA-2 can be continued in use with longer keys (paloalto).

Power of quantum computing stems from exploiting quantum mechanical properties whereby one qubit (a unit of information corresponding to a classical bit) may represent a superposition of both states 0 and 1. It allows parallel processing. Solving a problem in a quantum computer requires formulating the problem to be handled with such qubits. Integer factorization is one task which can be efficiently solved by using superposition states (Shor's algorithm). Thus, the RSA encryption, the basis of public key encryption, will be broken. Elliptic curve encryption is vulnerable as well.

Such a quantum computing algorithm is not known for, for example, AES, the standard symmetric-key encryption algorithm, though according to SecurityWeek, Grover's algorithm can reduce AES 256 to AES 128, halving the length of the key.

Vigenere's Description of Scytale Not as a Transposition Cipher

Some years ago, I pointed out that the scytale was not described as a transposition cipher as understood today before the nineteenth century in "Scytale Not As a Transposition Cipher".

Now I find Vigenere's description also seems to be something different from a transposition cipher.

Blaise de Vigenere, Traicte des chiffres (1586), describes the scytale (f.11). His source is Aulus Gellius' Noctes Atticae.

la Scytale des Lacedemoniens, inuention d'Archimede Syracusain, nous monstre assez en Aulugelle liu. 17. chap. 9. l'antiquité de ces occultes & desrobbees fortes d'escrire. C'estoit vn baston rond ou carré, d'enuiron trois doigts en diametre,long de pied & demy, autour duquel on reploioit comme vne longue liste ou bande de papier ou de parchemin, de la largeur de quelques deux poulces, en sorte que les entortillemens eniamboient fort dru & menu l'vn sur l'autre, à la distance seulement d'vn bon dos de cousteau, ou peu plus. Et apres l'auoir ferm' arrestee és deux bouts auec de la cire, & marqué le commencement, on escriuoit le long des faces sur les replis, tant que le subiect se pouuoit estendre, & qu'il y en pouuoit tenir : lesquels estans desueloppez, tous les mots, voire la plus grand-part des lettres se trouuoient couppees par le milieu, à bien grand' distance encore les vnes des autres ; sans qu'il fust possible de les rassembler, qu'on n'eust vn semblable baston adiuxté au mesme calibre, pour les y entortiller comme au precedant, & remettre le tout en son ordre & assiette deüe.

"on escriuoit le long des faces sur les replis" (one wrote along the faces upon the folds) appears to mean writing along the length of the baton, crossing successive edges of the strip. As a result, words are broken, with many letters cut in the middle. Given also that the width of the strip is as large as about two pouces (5.4 cm), this would not have been intended as a transposition cipher. It appears to be close to a scheme illustrated by Hulme [1898]:

 

Prince of Condé's Simple Substitution Cipher (1792-1800)

The Prince of Condé, the leader of a counter-revolutionary army of émigrés, used a simple substitution cipher with the Count of Provence (future Louis XVIII), Duke of Bourbon (his son), and Duke of Enghien (his grandson). I now uploaded a new short article about this: "Prince of Condé's Simple Substitution Cipher during the French Revolutionary Wars".

K4 Kryptos Secret Sold for Nearly a Million Dollars

The secret of the mystery of the undecoded cryptogram known as Kryptos K4 has been sold at an auction for nearly a million dollars (RR Auction).

Kryptos is a sculpture installed at the headquarters of the CIA in 1990. It features ciphertexts K1-K4, of which K4 (97 characters) remains unsolved despite attempts by crypto-enthusiasts around the world. The creator, Jim Sanborn, published hints on several occasions (Wikipedia), but it did not lead to a solution.

I have not paid much attention to this famous puzzle, but I occasionally wondered what it feels like to be the only person in the world to know the solution of the puzzle that is attracting world-wide attention. This was answered by an article that reported a scheduled auction to sell the secret. (I lost the article I read in Japanese, but I think its source was The Washington Post, 14 August 2025). Because of the fad, his residence had "unwanted guests" and some even threatened his life to get the secret. He had to equip his house with panic buttons, motion sensors, and cameras. The number of claimed solutions sent to him skyrocketed to tens of thousands due to submissions of "meaningless" AI-generated decryptions. So he began charging a $50 fee to decrease the number. After 35 years keeping the secret alone, Sanborn, then 79, said "I no longer have the physical, mental or financial resources" to maintain the code while he had other projects. So he decided to sell the secret in an auction on 20 November 2025.

What nobody expected was that the solution text was accessible to the public among Sanborn's papers in Smithsonian's Archives of American Art (AP 13 November 2025). In September 2025, writer and researcher Jaret Kobek and playwright and journalist Richard Byrne, hearing the news of the coming auction, hoped to find some hint to K4 but was unexpectedly stumbled upon Sanborn's original scrambled texts. They chose to call Sanborn, who decided to proceed with the auction because the encryption scheme was not revealed, though Kobek and Byrne did not agree to sign a nondisclosure agreement. The auction plan was changed to offer not only the secret of K4 but the entirety of his archive of related materials.

In the auction held at Boston, the materials were sold for $963,000 to an anonymous bidder (AP 22 November 2025). According to RR Auction, the winner will get a private meeting with Sanborn to be briefed about the purchased materials to receive not only the physical archive but also complete knowledge.

The purchaser's "long-term stewardship plan" is being developed." This appears to mean that the solution will not be revealed in near future, in line with Sanborn's wish. Kobek and Byrne do not plan to release the solution, either (The New York Times, 16 October 2025, quoted by RR Auction).

As I said above, I have not paid attention to Kryptos, but I did see a video released shortly before the auction by Richard Bean, whose email reminded me of the auction. Considering that Sanborn's hints have not allowed anybody to come up with a solution, he seems right in suspecting that K4 is "not a fair challenge" because of encryption errors.

 

Decoding Armstrong's Letter: Help Wanted for Madison Papers

A letter from John Armstrong in Paris to Secretary of State James Madison, dated 20 February 1808, remains to be solved. I learned of this from Ms. Angela Kreider, the current editor of the Papers of James Madison at the University of Virginia, who seeks help from the cryptographic community.

Many letters from Armstrong to Madison can be solved with a key reconstructed from decoded materials, but this one is in a different code.

If someone succeeds in solving this, please let me know or contact the editor.

See my new article "An Outlier Code in Armstrong-Madison Correspondence (1808)" for details.

Comments are also welcome. For example, I'd appreciate if someone can tell whether the graphic symbols occurring here and there in the sequence of numbers are a shorthand or a substitution cipher.

 

An Undeciphered Letter of Le Tellier to a General in Flanders (1657)

There is an undeciphered letter from Le Tellier to Marquis de Castelnau, dated 12 May 1657, for which I added an entry in "Unsolved Historical Ciphers". Below is my transcription. For a bit more information as well as Le Tellier's other ciphers, see the section "Le Tellier-Castelnau Cipher" in "Ciphers Early in the Reign of Louis XIV".

This may be a bit too short for cryptanalysis, but if the assignment of numbers is regular as in some of Le Tellier's other ciphers, there may be some chance. If someone succeed in solving this, I'd be eager to know.

Monsieur
Jay eu commandement de vous adresser la despesche du Roy qui sera cy jointe pour vous faire congoistre ses instructions sur la marche que Sa Ma.^te desire que vous fassiez avec les troupes estans au rendezvous de Rheimes et de Laon et de vous faire par^ent observer par ces lignes que le dessein de Sa Ma.^te estant 71 49 q ~4 57 3 ~34 q= "13 ~20 ~34 q ~3 a c 15 "12 ~13 ~9 4 & ~13 ~20 h- ss 16 47 56 13 ~14 14 ~30 l 3 rp 33 ~14 p 51 ap ~28 ~10 8 "34 ~3 4 18 ~30 19 ~18 15 ~23 "48 p ~53 J- x- ~3 "13 18 ~28 ~33 h- y- ~28 12 ~8 20 ~33 "17 51 20 f ~27 ~23 "33 ~28 z- ~4 c 31 "32 ~7 3 l 62 "12 ~35 13 ~38 ~23 "33 49 ~14 c 9 66 5~ 20 ~34 h ~37 t 5 p- ~30 l 14 ff 33 ~22 20 7 m- ~2 42 15 50 61 6 ~12 19 16 35 ~22 8 "25 ~38 J- o 15 ~23 "40 ~17 13 ~2 ~7 14 l 62 ~24 a p ap- 13 f ~28 47 51 h- ~28 ~3 20 14 49 ~13 2 ~7 ~4 h 20 47 m ~27 ap ss f ~28 "24 ~30 l 13 oo 33 "33 q= "14 51 ~34 h 31 m ~30 ap ~28 ~23 ~2 "32 "13 "24 ~4 & ~3 13 69 t t f ~28 ~42 ~53 72

I thank Alexandre Pillon for the information about this. Another unsolved ciphertext he provided before is also awaiting solution (Adam Starhemberg (1758)).

 

Reconstruction of a Venetian Cipher (1552)

I succeeded in identifying the mapping between cipher symbols and plaintext elements in a letter of a Venetian ambassador (1552) in ASVe, "CX Cifra, chiavi e scontri di cifra constudi successivi", Busta 13 f.36-37 (DECODE R1845), which is now presented in "Venetian Ciphers with Superscripts". When I first posted the article in 2020, I couldn't do this and I simply presented the ciphertext and its decryption separately.

Once the deed is achieved, it doen's seem so difficult to think of identifying the first two symbols "rp5 m3" as "QUEST A", because "rp5" recurs close to the end and "m3" appears in multiple times. This time, I noted the succession of two symbols "p3 p3" and "K2 K2", which seemed to correspond to "ta ta" and "sa sa" in the decryption, respectively. (Later, it turned out that the transcription "sa sa" should be corrected to "ha ha", though the matching was right.) With these clues, symbols occurring more than once were identified one by one.

Sometimes, I had to abandon my identification. For example, at an early stage, I thought "pp0" occurring close to the beginning and the end was "in" ("Do-m-in-o" and "in Italiano"). It was only when the work got close to completion that I found this symbol was actually "no" ("Do-mi-no" and "in Italia-no").

As always, part of my trouble was that I could not read the decrypted plaintext. Repetition of the symbols allowed me to correct some part of my transcription. Below reproduces my initial transcription.

... rp⁵ m³ g⁶ e² d³ m³
r³ pp⁵ c⁴ mp⁵ lp¹ l² mp⁰ m² p³ p³★ pp¹ ep¹ n² pp⁰ fp⁰ g⁶ n⁶ c⁸ g⁷ e³
n⁴ xp¹ r⁶ np⁵ v² c² q³ cp⁵ e⁸ ap⁰ f⁶ c³ cp⁵ c⁸ c⁶ cp⁵
rp⁰ p⁴ k⁸ K² K²★ h⁵ c⁶ r³ dp¹ c² e⁸ n⁹ f⁶ p³ m³ np¹ c³ h² lp⁵
cp⁵ p⁴ r⁶ ap⁰ h⁴ mp⁵ b² N⁷ n⁸ d² a² a⁸ lp¹ x² d⁴ A⁶ p⁷ p³ l⁸
fp¹ ep¹ m⁴ n⁴ np¹ ♀⁷ h⁰ p⁰ a⁷ m⁴ m³ c² l⁴ pp⁵ t² m³ ap⁵ z⁷ cp⁵ rp⁰
l⁴ c⁷ d³ n⁴ a⁷ rp⁰ g⁴ n⁴ cp⁰ ♀⁰ m³ cp⁵ d² t² e⁸ ap¹ f⁶ tp¹ n⁶
K² np¹ c³ v⁹ c⁶ c² c⁹ np⁵ ep¹ a⁸ mp¹ ap⁰ c⁷ e⁴ b⁸
A¹ p⁴ g⁶ n⁸ m³ rp⁰ ap⁰ n³ c⁶ a⁸ v⁵ ap⁵ R¹ d⁴ m⁶ lp⁵ c²
l³ ap⁰ N⁷ g⁶ d⁶ k⁹ pp⁰ t² e² c⁷ m² rp⁵ lp¹ ep⁰ mp⁰ f⁴ c⁶

[decryption]
Questa cosa gia molti mesi e solicitata da Domino Nicolo Villario ilquale &ts mosta di esser fidel serviton della scr^ta v^a sa sanuto molta difficulta a consegnirt &ts de qui si suspicana, et egli teattasse tate negocio con intelligentia di lei icr i fauoz delle raggion del R-mo Patiarcha et finalmente lo sa consiguito di quel modo et uedera li scr^ta v^a della copia del decuto es so fatto teadus di Todisio in Italiano, er sara i queste alliguo Gry

The recontruction confirms that the same cipher was used in 1552, 1554 and 1556 (DECODE R1845, R1846, R1847).

"Deciphering Mary Stuart's lost letters from 1578-1584" is available as Open Access

I received a full-text request from someone for my coauthored paper, "Deciphering Mary Stuart's lost letters from 1578-1584" on ResearchGate. To my dismay, ResearchGate does not allow me to send it but does not provide means to communicate it to the requesting person. I hope he will notice this post.

The requested paper is open access and can be freely downloaded at
https://www.tandfonline.com/doi/full/10.1080/01611194.2022.2160677

The pdf is 14.8 MB but the maximum file size allowed on ResearchGate is 3.7 MB. I looked for means to just sending an email with a link to the requesting person but there seems to be no such way. I have to say I'm not accustomed in navigating on this platform and it may be that I miss something.

I hope he will notice this post, or at least think of googling the paper title to reach the right website.

Telegraph Operator Leaked Union Commander's Name in US Civil War?

Ciphers in newspapers clippings in the papers of mathematican Charles Babbage are presented in my new article "Charles Babbage's Clippings of Newspaper Ciphers". Only one among the twelve remains unsolved, in which only the name of a brigade commander appears to be in cipher:

THE COMING MAN. - The New York Tribune states that a telegram was recently despatched to the Federal army directing to whom the command of a brigade was to be intrusted, and that the operator at the telegraph station declared the person selected to be Amjyrdkowasejow Deabxpeop. [annotated "Times Tuesday 13 Jan 1863"]

Did the telegraph operator leak the name? Could it be so important information to be carried in a newspaper in London?

(Edit: After first uploading this, I added one unsolved ciphertext from Evening Standard, 12 February 1870, seemingly in a simple substitution cipher.)

Emperor Charles VI

I mentioned Emperor Charles VI's letter partly in cipher in "Habsburg Codes and Ciphers", based on materials presented by Jakub Mírka. Now machine translation allows me to more or less read his paper, Jakub Mírka (2012), "The early modern cipher correspondence in the noble family archives deposited in the State Regional Archives in Pilsen" (ResearchGate) (in Czech according to Google Translate).

The letters are from Emperor Charles VI to Leopold Viktorin von Windischagrätz in the Windischgrätz Family Archive in the State Regional Archives (SOA) in Pilsen (in the Czech Republic).

One was sent when Leopold Viktorin stayted in The Hague as an envoy.
3 February 1720 (DECODE R5020; original R5019; key R5017)

Interestingly, the Emperor informs the recipient that the new cipher would be supplied in this or the next despatch to be used exclusively with him, while the old one would be used with the court office.

Other letters belong to the period when Leopold Viktor served at the congress in Cambrai (VUB).
13 April 1720 (DECODE R5022; original R5021; key R5018)
24 July 1720 (DECODE R5023; key R5018)
11 April 1722 (DECODE R5024; key R5018)

Another undeciphered letter interesting to me mentioned by Mírka is one from Johann Wenzel, Count of Gallas (Wikipedia), imperial ambassador in London, to Prince Eugen of Savoy in 1711 during the War of the Spanish succession. He says this is supposedly important.

Emperor Maximilian II's Cipher Letters

I already described the work by Kopal and Waldispühl on cipher letters of Emperor Maximilian II (1575) in "Habsburg Codes and Ciphers". The letters concerned are summarised in Table 1 of their paper in HistoCrypt 2021, to which the following shows record numbers in the DECODE database. (I present this as my personal note because it takes time for me to type the DECODE database name.)

R1472: Johan Kochtitzky to Maximilian II, 15 November 1574 "Letter D"
R1473: Johan Kochtitzky to Maximilian II, 22 February 1575 "Letter E"
(and in a different cipher)
R1407: Maximilian II to ambassadors in Poland and Lithuania, 23 December 1575 "Letter C"
R1412: Maximilian II to ambassadors in Poland and Lithuania, 24 December 1575 "Letter B"
R1471: Maximilian II to Johan Kochtitzky, 5 July 1575 "Letter A"