William Blencowe's "Safest and Most Expeditious" Cipher

I uploaded a new article "William Blencowe's "Safest and Most Expeditious" Cipher". Blencowe was a grandson of the celebrated mathematician and codebreaker, John Wallis.
The example ciphertext consists of an interesting mix of single letters and bigrams:

a.c.e.o.t.ds,th.al,th.an,th,es,an,my,be,m.n.t.o.nd,jo.H.sh,y,in.y.
A.w.n,th,e.de.in.pi.sa.I.A.g.su.r.to,ye,ho.e,th.c.wth,de.re,en.t.at,
r.il,ti.A.n.nb.te.sts,nd,ri.rm.ot,re,d,n.m.m.r.ar,nd,ar,ty,us.i.m.c
in,a.e,d,h,ro.to,y.ig.&,of,to,ou,a.b.d.g.f.p,no,n.is,d,a.p,k.
ye,b.th.th.of,u.m.n.hl.th.t.S.t.n.e.ye,xt,u.w.A.ho,en.o.w.Ja.I
th,l.F.pe,n.e,h,hi.rs,ar,ty,la.ki.a.r.in,e.fo.to.m,w.tw.th.nd,ng,Sr,
no.le,at,ey,th.gh,ar.ed,an.e.w.co.h.n,h,a.n.e.E.ey,pa.ou.d,an,is,as.
r.p.m,g.f.c,a.n.do,ll,b.m,d.g.b.d.m,p.q.b,s.r,d.c,a.n

After all, however, this is essentially a columnar transposition cipher with some additional twists. Using bigrams may mislead the codebreaker at first, but once transposition is suspected, they would help codebreaking rather than prevent it.

Can a Lost Encoding Format be Recovered by Analysis?

It's now a decade ago that I read in a newspaper article that data obtained on Mars by Viking spacecraft could not be read 25 years after the landing because the format was lost (The Asahi Shimbun, 20 January 2014). The case is also mentioned in a report on long-term data preservation by a Japanese think tank, CRDS (CRDS-FY2012-WR-07).
The source seems to be a news release of the University of Southern California (Spaceflight Now):

"The data were on magnetic tapes, and written in a format so old that the programmers who knew it had died," Miller said.
Eventually, NASA was able to recover the data from printouts, luckily preserved by Levin and Straat - and so, Miller was able to pore over the numbers.

After all, the issue is not about loss of a data encoding scheme but physical format of the magnetic tapes.

I got interested in this news because I was wondering whether "codebreaking" is possible for media data encoded on, say, DVD without knowing the format. (The compromise of the encryption system (Wikipedia) of DVD assumes knowledge of the format, and is thus another matter.) Considering the sheer number of pages of format documentation, I think it is near impossible. But of course, relying on secrecy of the scheme is not a good idea for cryptographic security. Security should rest on the key being kept secret (Kerchoff's principle).

By the way, the Viking data recovered in the 1990s was used to claim finding evidence of an organism on Mars (Miller's site, Levin's site). But the result is not established (Wikipedia).

Two More English Ciphers from the 1650s

I've been going through my notebook file these days, and uploaded some materials I left unfinished before. Now, I added two ciphers (Richard Browne, John Bramhall) in "King Charles II's Ciphers during Exile".

J.F.W. Herschel's Cipher Puzzle

I've been interested in ciphers that allow multiple readings (a Venetian example).
So, I took a note when I read about a ciphertext that yields two readings, posted by tonybaloney at:
http://www.aerobushentertainment.com/crypto/index.php?topic=36.60
(now it seems the link has changed).
The ciphertext (A) and the two readings (B,C) are as follows:

(A)Xabnsly ngpwpdetlews tbbbtzl aobl stheingdnxmccvv
(B)Several philosophers observe that chloroplatinate
(C)Sing, Celestial Muse, the destroying

(A)hclzepsf xo qskxybbbbui
(B)solution on silverplate
(C)wrath of Achilles,

(A)Egtubatjkh fba lwipizix eqjbnasv nfvj yjcin
(B)reproduces the luminous spectrum with great
(C)Peleus’ son, what myriad woes it

(A)cjzvekzxy gf nbyr gzrefcwxianst
(B)vividness in blue fluorescences,
(C)heaped on the Grecians,

(A)Jxkivu v xcnukwcxpv ifnnszp't tpdvm
(B)whilst a coppersalt insolated might
(C)Many a valiant hero’s soul

(A)lqaauuqrauaqqvso up mfijtxyz.
(B)photographically be coloured.
(C)dismissing to Hades.

Now, I find this ciphertext was posted by Klaus Schmeh on his blog Cipherbrain back in 2016: Wer knackt die Verschlüsselung des Astronomen John Herschel?. The article shows the source: The Photographic News, 5 January 1866 and identifies the author of the ciphertext as J.F.W. Herschel (1792-1871) (Wikisource). The blog readers found out additional information.
The weekly magazine (Google) carried the puzzle on 5 January 1866 (p.5-6), the solution (B) provided by a reader the next week (p.23), and Herschel's correct solution (C) the next week thereafter (p.35). After all, the reading (B) was wrong, and this cipher is not about double reading.
The readers of Cipherbrain worked out the general principle of this cipher: schorsch pointed out the first two words can be explained by word-by-word Caesar cipher, Norbert demonstrated this works for every word, and Thomas found the shift, counted in reverse direction, is the number of letters in the word plus 1, 2, 3, 4, ....
In the following, (a) is the ciphertext, (b) is the number of letters in the (deciphered!) word plus 1, 2, 3, 4, ..., (c) is the result of reverse-shifting, and (d) is the plaintext word.

(a)Xabnsly ngpwpdetlews tbbbtzl aobl  stheingdnxmccvv
(b)4+1=5   9+2=11       4+3=7   3+4=7 10+5=15
(c)Svwingt cvelestiatlh muuumse thue  desptyroyixnngg
(d)Sing,   Celestial    Muse,   the   destroying

(a)hclzepsf xo    qskxybbbbui
(b)5+6=11   2+7=9 8+8=16
(c)wraotehu of    acuhilllles
(d)wrath    of    Achilles,

(a)Egtubatjkh fba     lwipizix eqjbnasv nfvj    yjcin
(b)6+9=15     3+10=13 4+11=15  6+12=18  4+13=17 2+14=16
(c)Prefmleuvs son     whtatkti myrjviad woes    itmsx
(d)Peleus'    son,    what     myriad   woes    it

(a)cjzvekzxy gf      nbyr    gzrefcwxianst
(b)6+15=21   2+16=18 3+17=20 8+18=26=0
(c)hoeajpecd on      thex    gzrefcwxianst
(d)heaped    on      the     Grecians,

(a)Jxkivu  v       xcnukwcxpv ifnnszp't tpdvm
(b)4+19=23 1+20=21 7+21=28=2  5+22=27=1 4+23=27=1
(c)Manlyx  a       valsiuavnt hemmryo's socul
(d)Many    a       valiant    hero's    soul

(a)lqaauuqrauaqqvso up        mfijtxyz.
(b)10+24=34=8       2+25=27=1 5+26=31=5
(c)dissmmijsmsiinkg to        hadeost
(d)dismissing       to        Hades.

What remains unknown is (i) how the decipherer can know the number of letters in the deciphered word and (ii) how the decipherer can identify the letters to be discarded. The latter may be left to the decipherer's insight, but (i) is indispensable to allow proper deciphering.
Herschel presented this cipher as a challenge to believers of "an axiom that there is no cipher which cannot be read." I guess that in trying to make the puzzle more difficult, he forgot that the scheme need to be (difficult but) invertible.

A Cipher between Emperor Charles V and Young Prince Philip (1545)

A letter with a ciphered paragraph from Charles V to Prince Philip (1545) is presented on Spanish Ministry of Culture's website (pdf) and PARES' facebook page. The cipher turned out to be the same as the one broken by George Lasry and Carlos Köpte independently in 2023. So, I promoted the cipher as "Charles V-Prince Philip Cipher (1545)" in "Ciphers during the Reign of Emperor Charles V".

Variable-length Figure Cipher Used by Gilbert Gifford?

Speaking of variable-length figure cipher mentioned yesterday, I found in my notebook file a possibly relevant record:

"The words in italics are in cipher, only partly deciphered. The cipher for the most part consists of figures which run on without a break, and are thus capable of various solutions, according as they are taken as single or double numbers; and this sometimes prevents the deciphering of one passage by the aid of another."
From: 'Appendix: January 1588', Calendar of State Papers Foreign, Elizabeth, Volume 21, Part 1: 1586-1588 (1927), pp. 661-671. URL: http://www.british-history.ac.uk/report.aspx?compid=74826&strquery=cipher Date accessed: 06 May 2013.

This note belongs to a letter from Stafford to Walsingham from January 1588, but may refer to an enclosed letter from Gilbert Gifford (under the pseudonym of Francis Hartley) to Thomas Phelippes (M. Wilsdon).
Inspection of the original manuscript is desired.

Variable-length Figure Cipher used by Duke of Lorraine (ca.1620?)

I succeeded in reconstructing a cipher used in a letter to the Duke of Lorraine (ca.1620?) and uploaded it in a new article, "Variable-Length Figure Cipher of Duke of Lorraine (ca.1620?)". I abandoned this before, but I took it up again and this time, two occurrences of the word "temperament" provided a first clue. Unexpectedly, the cipher employed variable-length symbols. That is, code symbols consist of one to three symbols. Since the figures are written without a break, there was some difficulty in identifying code symbols corresponding to plaintext segments.
This kind of variable-length symbols written continuously without a break are often seen in Vatican ciphers. It is yet to be studied how this system came to be used by the Duke of Lorraine's correspondence.

Codebreaking of Sir Robert Southwell during the Popish Plot

The Popish Plot may refer to "a period of extraordinary political tension that took hold in England in 1678" (Fictitious treasons: 'The Popish Plot') instigated by revelation of a fictitious plot known by this name.
My notebook included a reference to Sir Robert Southwell's deciphering during this period since 2009, but I have not known whether this involved codebreaking or used a key obtained in a non-cryptographical way. The other day, I found Southwell himself wrote this was "without a key", which makes it interesting enough to be included in an additional section in "Ciphers of Coleman's Correspondence Discovered in the Popish Plot".
It's a pity it is not known specifically what cipher was broken by Southwell.

Duke of Ormond's Ciphers during the 1660s

I added a section "Marquis of Ormond's Correspondence" in "English Ciphers during the Restoration Period". It covers some reconstructed ciphers used by the Duke of Ormond, the Earl of Anglesey, the Earl of Arran, and the Earl of Longford.
The Ormond-Anglesey Cipher used in 1663-1664 appears to be based on a printed template of DECODE R433. This shows the template was used as early as 1663.

Cryptiana is now HTTPS-Enabled

Belatedly, I enabled HTTPS in Cryptiana. The other day, I happened to access Cryptiana on my mobile phone, and got a warning message that it's not secure because it is not in https. I found only one click is needed to enable HTTPS. Hopefully, mobile users have one less concern in using Cryptiana. It seems old links beginning with "http" are automatically redirected to "https" URLs.

Ciphers Used in Letters of Oliver Cromwell, Henry Cromwell, and Others

I updated an old article "Codes and Ciphers of Thurloe's Agents" for the first time since 2012. The original article was based on Thurloe State Papers in print, but I noticed the original manuscript is in Add MS in the British Library, based on which I added a new section "BL Add MS 4166". Although the title of the article refers to "Thurloe's Agents", ciphers used in letters of Cromwell (Add MS 4166, f.87-91) and his generals and ambassadors are also covered.
One scheme interesting for me is a kind of polyalphabetic cipher for Henry Cromwell (1656), in which a plaintext letter is represened by a pair of figures, of which the difference indicates the letter (Add MS, f.77-78, 118-119).

"A new Book of Cyphers" ... about Intertwined Initials

I came across a book, William Parsons' A new Book of Cyphers (1704)(Google) during a web search. For a moment, I expected it was about an invention of a cryptographic method, as in Samuel Morland's A New Method of Cryptography (1666), which I descrbied in "Samuel Morland's "New Method" Used for Charles II's Ambassadors". 

Actually, the "cipher" of this book refers to a symbol design made of intertwined initials. 

Such "ciphers" (or chiffres in French) are quite common and I mentioned them in "Great Ciphers of Napoleon's Grande Armée" (in the context of Empress Marie-Louise), "ウイリアム・ブレア「暗号」（1807）（『リース百科事典』）" (quoting from a definition of "cipher", "a kind of enigmatical character, composed of several letters interwoven together, fancifully" from Rees' Cylopaedia), and possibly others. Searching for "elizabeth cipher" (without quotes) on Google gives a Wikipedia page "Royal cypher" before my article about Elizabethan codes and ciphers.