A few weeks ago, some new ciphertexts pinged on my Cipher Mysteries radar: the story goes that they had been found just after WWII in wooden boxes concealed in the wall of an East London cellar that German bombing had exposed. Hence I’ve called them “The Blitz Ciphers”, but they’re probably much older than the 1940s…

They were handed down to the discoverer’s nephew (the present owner), who now finds himself caught between a desire for relative anonymity and a desire to know what they say. So far, he has been good enough to release three tolerably OK photos from a much larger set he took: but will these be enough for us to crack their cipher?

[Of course, despite the story’s plausibility, I have to point out that this might conceivably still be a hoax designed to make cryptographic fools of us: but if so, it’s such a classy job that I really don’t mind. 🙂 ]


Generally, the Blitz Ciphers’ writing appears to have been added in two hands: a larger, paler, more calligraphic presentation hand, and a smaller, darker, tighter annotation hand. While the presentation hand serves to establish the content and layout structure, the annotation hand is restricted to supplementary paragraphs and additional short notes apparently explaining key letters or terms.

Broadly speaking, the text on the first page (the ‘title page’, above) seems to have been laid down in three sequential phases:-
* #1: the circular ‘boss’ / ‘plaque’ and the two large paragraphs – large presentation hand, brown ink, quite faded in places.
* #2: the third large paragraph at the bottom – mid-sized annotation hand, brown ink.
* #3: the annotations to the other paragraphs – small-sized annotation hand, darker ink.
This general construction sequence seems to hold true for the other pages too.

The second page we have contains two curious diagrams: one a drawing of an octagon (though note that there is a square missing from the lines connecting all the vertices of the octagon), and the other an abstract tree-like representation of something unknown.

Our third page contains a large “John Dee”-like 20×20 square table, where each grid square contains individual cipher letters. The table has an array of red dots gridded within it, where each of the 16 internal red dots is surrounded by a letter repeated four times in a 2×2 block. Red dots near the sides all have two dotted square characters on the edge beside them, apart from a single one near the top right, suggesting a possible copying error. There is also a single correction (near the top left of the 20×20 table) made in the presentation hand.

The support material appears to be handmade paper (I don’t have access to them to look for a watermark, sorry!), while the inks for the two hands appear to be quite different. Though I can’t prove it, I suspect that the larger presentation hand was written using a quill pen (suggesting genuine age or some kind of ceremonial presentation aspect) while the smaller annotation hand was written several decades later with a metal nib. They could possibly have been written by the same person using different pens, but differences between the two hands argue against this.

My initial dating hunch was the first layer could well be 16th century and the second layer 17th century: but having said that, the whole thing could just as well be much more recent and instead have been deliberately written in that way to make it appear ‘venerable’ and old-looking. (More on this below.)

The Blitz Cipher Alphabet

The letter forms are clear, distinct, and upright: the presence of triangles, squares and circles and various inversions perhaps points to a cryptographer with a mathematical or geometric education. It’s closer to a demonstration alphabet (designed for show) than a tachygraphic script (designed for repeated large scale use). Here’s the provisional transcription key I’ve been working with:-

Despite some apparent ambiguities in how to parse or transcribe the various cipher shapes used, the fact that the 20×20 table has only a single letter in each cell is a fairly strong indication that each table cell contains a single cipher glyph, suggesting that about 50 distinct characters are in use. The text has a language-like character frequency distribution, with “:” [E] being the most frequently used character (the “tilted Jupiter glyph” [B] and the “joined-up-II glyph” [D] are #2 and #3 respectively). The “Greek phi glyph” [S] often appears at the start of lines and paragraphs.

I’ve shown all this to some cipher historians and codebreakers for their early reactions. Glen Claston notes that “the alphabet is based on the types of symbols used by astrologers, with a few I recognize as alchemical symbols“, though – inevitably contrariwise – I suspect this might well be a coincidence arising from the simple shapes and symmetries employed. Peter Forshaw suggests parallels with some geometric cipher shapes used in Della Porta’s “De furtivis literarum notis“, though Tony Gaffney similarly cautions that such “shapes were very common back then, the numerous ‘ciphers of diplomatic papers’ in the British Library are full of them“.

The Blitz Cipher System

As with the Voynich Manuscript, the peaky frequency distribution probably rules out complex polyalphabetic ciphers (such as Alberti’s code wheel and Vigenere cipher): yet it doesn’t obviously seem to be a simple monoalphabetic substitution in either English or Latin (but please correct me if I’m wrong!)

Unlike the Voynich manuscript, however, I can’t see any obvious verbose cipher patterns significantly above chance: so the main techniques left on the cryptographic smorgasbord would seem to be:
* a homophonic cipher, like the Copiale Cipher (but if so, the encipherer didn’t flatten the stats for “:” [E] very well)
* a nomenclator cipher (i.e. using symbols for common words, like “the”, “Rex”, or “Mason” 🙂 )
* an acrostic / abbreviatory / shorthand cipher.

All the same, there are some intriguing patterns to be found: David Oranchak points out that “‘SBDBlDMDBl’ is an interesting sequence, since it is length 10 but only consists of 5 unique symbols.” I suspect that the presentation hand uses a slightly different enciphering strategy to the annotation hand, which possibly implies that there may be some kind of homophone mapping going on. The fact that there is also an annotation applied to a single letter [c] on the title page may also point to a nomenclator or acrostic cipher.

Personally, I’m intrigued by the circular ‘boss’ at the top of the title page: this has three letters (C, M and E) calligraphically arranged, i.e. the two dots of the colon have been separated above and below the M. To my eyes, this looks suspiciously like a cryptographic conceit – might it be the case that “:” (E) is in fact a kind of letter modifier? For example, it might encipher a repeat-last-letter token (if the text had a lot of Roman numbers), or perhaps a macron-like “overbar” superscript denoting a scribal abbreviation (i.e. contraction or truncation). Something to think about, anyway!

As for the plaintext language: if this was indeed found concealed in an East London cellar, English and Latin would surely be the main suspects, though Tony Gaffney tried Latin and couldn’t find any kind of match.

Blitz Cipher Theories & Hunches

If you’re expecting me to start speculating that these documents were from a 16th century Elizabethan secret society frequented by John Dee and/or William Shakespeare, sadly you’ll be quickly disappointed. Similarly, though I concur heartily with Glen Claston that these genuinely intriguing ciphertexts may well ultimately prove to be high-ranking 18th century Mason or Freemason ciphers, it is just too early to start saying. We simply don’t know as yet enough of the basics.

What I personally have learned from the tragically fruitless, long-term debacle that is Voynich Manuscript research is that speculative theories are almost always a hopeless way of trying to decipher such objects. Hunches are cool and useful, but they need to stay restrained, or everything goes bad. Please, no theories, let’s try to crack these using the proper historical tools at our disposal!

48 thoughts on “Announcing “The Blitz Ciphers”…

  1. John Willemse on December 23, 2011 at 7:19 am said:

    Very interesting Nick! Might be a hoax, but it would be an elaborate one at that! Any knowledge about releasing a transcript or complete set of photos, so we cipherheads can take a crack at it?

  2. John Willemse on December 23, 2011 at 7:22 am said:

    P.S. Have a merry Christmas and a happy healthy new year! 🙂

  3. John: the first step was to give everyone a proper look at it, but yes, the transcription is next… 🙂 Happy X-mas to you too! 😉

  4. Couple of titles that might be relevant, maybe
    Peter Johnson, Romano-British mosaics

    and another called
    The Byrom collection
    bibliog details at the foot of this article:

  5. Ooh!
    I recently did a lot of research about the calligraphy/signatures on a Japanese “box” and its matching lid. Several of the characters on your “sample” match exactly some of the brushstrokes needed to form the signature that appears on “my” Japanese pottery box: Kinkozan Sobei. (?) I recently gifted the box to a good friend whose mother had lived for a while in Japan in the 1930’s and ’40s

  6. The handmade paper may be rice paper.

  7. The shape of the diagrams (not quite circular) suggest, to me, a gem-cutter’s instructions/diagrams for faceting an oval stone. Another likelihood that comes to mind would be instructions for laying ornate tile inlay patterns. (?)

  8. By laying ornate tile patterns, I had in mind the very elaborate tiles that appear on many mosques and muezzins “towers”. Surely, some tiles had to be designed to fit cylinders, domes, arabasque/floral patterns.

    Many of the tiles may have been made from diagrams lightly impressed upon large flat pieces of clay before cutting, not quite all the way through, for the first (bisque) firing. The tiles would then have had a color/glaze applied before the second, final firing. The finished tiles (if the geometry of their sides and depth of the cuts had been correctly calculated/diagrammed) would have been elegant, closely fitted “mats” of gorgeous color.

    Probably, the most important part of the design process would have been the calculations for the angles necessary to form curved surfaces out of straight-angled hexagon tiles. (?)

  9. One last comment (referall):


  10. Brighton Beach Royal Pavilion. Henry Holland. John Nash. (?)

  11. The “circular boss” script is

    Nast a’ liq

  12. Bobbi: possibly, but taken as a whole I’m pretty sure it’s far closer to the world of cryptography than to the world of calligraphy.

  13. North’s “Avery Hill” mansion
    Eitham Hill, London

    …bought by LCC in 1902

    1906 opened as “first residential training college for (women) teachers….

    “(North’s) was surely unique and , before it was destroyed during a Second World War bombing raid, outshone either of the other two extant baths….”

    I’ve lost one of my notes w/ref to the architects who worked on North’s “turkish bath” upgrade to the already huge mansion. I’m sure you’ll have no problem following my trail. Thanks for bearing with me (and my compulsive (?) file clerk’s view of the world.

  14. I found my notes:

    Colonel John Thomas North
    Avery Hill, Eltham
    Remodeling/Turkish Bath done by Thomas W. Cutler (partially) and completed by Cutler’s assistant J. O. Cooke

    The site is now the “Mansion Campus” Univ. of Greenwich.

    I have not been able to download the photograph of the Turkish Bath, but the patterning of the tile walls seem to match the drawings.

  15. I printed a copy of the postcard photo of the Avery Hill turkish bath. Eerie tile work! Each set of tiles (on the walls below the arches) presents what looks (to me) like the portrait of a man whose dark hair has been pomaded and parted midline on his skull. What looks like a “muttonchop” beard just adds “evil portent” to what should have been gorgeous tile-work. Eww!

  16. Bobbi: …but muttonchops were the height of fashion! Toothbrush moustaches similarly slipped out of fashion, though for rather more direct reasons. 🙂

  17. Back to the drawings:

    I now see that the markings on each “tessera” seem to indicate its color and placement. So, match the drawing with figures in the photo. Do you see what I see?

    I am now wondering if, in a fit of spitefulness, the contractor who had been fired gave instructions to his assistant to “tweak” the color scheme. (?)

  18. The letterhead “boss” could possible mean “Cutler Masonry Engineering” (?)

  19. Wait a minnit! One more comment:

    While I was locating Greenwich University grounds on the map, and zeroing in on Eltham Road, I noted a comment re Sir Thomas More’s daughter and her husband owned/occupied the mansion on the neighboring property. So, which daughter? Margaret (Roper) or Elizabeth (Dauncey) ?

    You might enjoy reading a novelization by Vanora Bennett, Portrait of an Unknown Woman. I bring this up only because of my earlier comments re the eerie patterning of mosaics in North’s turkish bath. Skulls. Thomas More’s skull ended up in the Roper’s crypt (if I remember correctly). I’m going to re-read the book again for the third time!

    Could be Vanora Bennett is a neighbor of yours?

  20. And then there is “Descartes Bones” by Russell Shorto. The bones did more travelling than Descartes ever did while he was alive.

    Copernicus’ skull remnant was disinterred. From TWO hairs, a DNA was done. From a fragment of skull, forensic artists drew a portrait of Copernicus, long mandible and all.

  21. Sorry ’bout that, Nick! I do tend to wander off the beaten path. Having taken drafting classes “way back when”, I think what we are looking at are notes that were meant to supplement the plans and drafting for North’s mansion.

    One thing I’m wondering is: did the plans, drawings, and notes ever indicate the system for heating the water and/or the “hot house” conservatory?

    Have you approached Greenwich University’s Mansion Campus administration for historic records? Probably most of the records were acquired by the LCC (London City C…..?). I suspect there may be a treasure trove awaiting your perusal.

    I live in the US. I don’t have university credentials. I’m hearing-impaired and read lips/body language to keep “on track”. So, please forgive my monopolizing your great website’s “Leave a Comment” pages.

  22. Bobbi: I’ll have a trawl along the way for this, see what I can come up with… 🙂

  23. As a visitor to this site I must admit I am interested in this article. However the lack of references to other sources or (from looking around the internet) the lack of related news items makes me sceptic. Is it possible to have some links to other articles related to this work?

  24. P: I’d like exactly the same thing myself – I’ll go back and ask the owner of the photographs if there’s any chance of an update.

  25. For me the glyphs bear a lot of resemblance to sanskrit/brahmi, but as I do not know the language itself I can’t say it is such. Yet the ‘plague’ resembles sanskrit way too much.

  26. The Letterhead “Boss/Symbol” that appears on the first page is most likely the initials for the construction company that built the Turkish bath:

    “C” “M” “E” (Cutler was the contractor)

    The style of the design could very well be adapted from Islamic/Muslim cursive style
    Nast’a lic.

    Nick, were you able to backtrack on my research/lead?

  27. By “Boss” “Symbol”, I was referring to the circular “logo” of the “letterhead” that “M” refers to as plague.

    I understand that Nick is some day going to “trawl” along the leads/references I was able to make in my earlier post.

  28. Another first time visitor here. By the way: fascinating site, thank-you! I offer a few observations on this text.

    The text is certainly written with a nib or quill pen held by a right-hander. (Strokes that slope down to the left are very fine, strokes that slope down to the right are heavy.) In the smaller (“annotation”) writing, a few strokes shown width varying with pen pressure, which is more typical of a steel nib. (When you do this with a quill, you generally make a mess.) Interestingly, more than two widths of nib was used. While this is not utterly impossible for an old text (e.g. Nick has suggested two writers), it also kind of whispers “calligraphy set!”

    Judging by the shapes of the uncut edges, none of these are not recto and verso of the same sheet. Since the photographs we have been shown are said to be incomplete, that doesn’t mean much. However if such fine paper was left blank on one side, it makes great age less likely.

    I have difficulty feeling that this text is very old, for several reasons:
    1. While the octagon diagram resembles ones found in mathematical and magical treatises of great age, the network of hexagons actually looks a great deal like a very modern type of mathemtical diagram called an “undirected graph.” Graph theory has been studied for nearly 300 years, but so far as I can tell, this type of diagram was only invented in the late nineteenth century.
    2. It appears to be written on heavy hand-made craft paper with the edges not trimmed. Such paper is either very old, or a modern revival. And I don’t think it is very old.
    3. Apart from the blotches of discoloration, the paper on the first 2 pages is very white. Much whiter than book pages in my possession that were made in the nineteenth century.
    4. The circle at the bottom of page 2 has almost certainly been drawn with a set of compasses, and I think the rondel was too. In both cases, the circle is almost perfect, except that the the weight of the stroke falls off on the hardest part of turning the compasses. In the one at the bottom of page 2, the slight blemish at the start/stop point is also fairly clear. It is less clear on the rondel, but I think it can be seen near the 10 o’clock position — typical for a right-hander using compasses.
    5. On the left hand edge and near the bottom of page 1, there are marginalia that indicate to what they refer with underlines that turn into indicating lines pointing to the marginalia. This is a modern proof-readers’ mark. Of course it is not impossible that this convention has been invented more than once, but it makes me go “hmmm.”
    6. In various points in the staining, the stains seem to avoid the ink lines. This suggests that a hydrophobic or antifungal material in the ink has diffused into the surrounding paper. This is common with modern ink; not so much with traditional ink.

    Many of the glyphs seem to have known antecedents from various scripts, but there are quite a few distinct ones; some strongly resemble Greek, some astrological symbols, and some closely resemble Devanagari with slight distortions. Many of them appear in variant forms, upside down, backwards, with dots and bars etc. This is a relatively quick way to fill up a 20 x 20 grid!

    The symbol in the rondel has probably been deliberately made to resemble “Om” in Devanagari, but it isn’t (nor in any other Indic script, so far as I can tell.)

    The 20 x 20 grid could be a Battista-style polyalphabetic, but if so, 20 is a very small alphabet, and the CT distribution should be very flat.

    All this suggest to me a homophonic cipher, in which the cipherer constructed his alphabet from a variety of scripts, using whatever he found mysterious or attractive. A good homophonic of this length could be quite challenging, but this one seems to see far too many repetitions, and too non-flat a distribution, for a good homophonic.

  29. Roger: thanks for your detailed comments, much appreciated!
    * I’d agree that it’s either genuinely old or a fairly heavyhanded modern fake: it doesn’t really fit inbetween.
    * The 20×20 has a great deal of explicit internal structure and also signs of copying errors: there seems to be little chance that this is a polyalphabetic grid of any sort.
    * The whiteness of the paper isn’t inconsistent with age, if it was indeed stored in a sealed box in a cellar.
    * The symbols in the roundel appear directly in the main text itself, so merely appear to be calligraphic / presentational renderings of them.
    * And yes, if it’s using a homophonic cipher, it’s a badly chosen one, though I don’t myself know how widely known good cryptography practice was at different eras. From the large number of poorly constructed diplomatic ciphers found in the archives, it would seem that best practice was a thing only rarely employed!

    May I please ask what your inference is from the apparent use of compasses in this document? Medieval scribes used a circinus, and dividing compasses appear extensively in the iconography of masons (both genuinely historical ones and the speculative freemason traditions) and architects (Filarete depicted one in his doors to St Peter’s Basilica in Rome circa 1445), so it isn’t obvious to me what this would imply here. Thanks!

  30. John Penderton on March 7, 2012 at 12:55 pm said:

    Fascinating observations, Roger. Just one small thing I might point out. The variation in nib size is not necessarily significant. It could either be purely for design purposes – the scribe obviously had a high aesthetic sensibility – or it could just be the result of nib trimming. Scribes frequently needed to resharpen their quills by cutting across at 90 degrees to the slot. The nib was originally shaped either side of the slot and usually tapered towards the end, resulting in the nib width slightly enlarging at each cut (if you see what I mean). Hope this helps.

  31. John Penderton on March 11, 2012 at 10:48 am said:

    Another small comment on the whiteness of the paper. It looks to me as though these documents have been thoroughly soaked at some time. I don’t know much about these things, but if the water had a high alkili content, wouldn’t this have had a bleaching effect? Just a thought.

  32. bdid1dr on March 20, 2012 at 5:00 pm said:

    By the way, another word for the circular “boss” could be a “placque” if it were to be stamped into wet concrete.

    Were you able to get to Greenwich University’s Mansion Campus to compare the documents with their file on the Colonel North’s mansion?

  33. Diane O'Donovan on April 17, 2012 at 9:00 am said:

    re bdid1dr’s remarks

    I agree this looks like a plan for tiling. Thomas W. Cutler was a name in Art Nouveau style and tiling, a Fellow of the architectural society and author of a couple of books including a grammar of Japanese ornament and design (now in Dover Press reprint, which suggests it’s good) and others on Japanese and Turkish tile work.

    I daresay he was a mason too. But the characters, I’d say are a westerner’s version of Korean or of Hiragana.

    He’s mentioned in a book about Crosby Place (near Bishopsgate street, now demolished) – online at

    Cutler is listed on page 3 (13 in the digitised version) as an honorary member of the survey committee.

    The same text outlines events of 1466, including reference to a Genoese merchant, and to the presence – below the newly erected stone house at Crosby place – of Roman tesselated pavement (mosaic) i- p.15 (25 of the digitised version).
    Articles on same were published and are referenced.

    Apparently not all the mansion was demolished.

    This image claims to show the magnificent Crosby Hall crest, so perhaps the building – or part of it – was saved and moved to the Chelsea embankment from Bishopsgate.


  34. bdid1dr on April 17, 2012 at 7:18 pm said:

    I’ll try to expand on my earlier posts: Because the design of the plans was for the building of a turkish bath in Col. North’s already existing mansion, I immediately thought “turkish” tile work Hence my “take” on the letterhead symbol. What Nick calls a “boss” (as in embossed letterhead), I saw as a European adaptation of N’astalique writing. Beautiful calligraphy.

    Anyway, has anyone followed my lead to Greenwich University’s Mansion Campus. They tell about their Library building’s history. Fascinating (except you get only a very brief look at the entryway of the building’s remodelling). I think they also give you a brief glance at the glass conservatory that Colonel North had constructed at the same time as the Turkish bath.

    Ennyway…I found the one postcard photo of the bath to be gloomy, if not macabre.

  35. bdid1dr on April 17, 2012 at 7:35 pm said:

    Greenwich University calls it their “Mansion Campus” for good reason: Colonel North was viewed by his contemporaries/neighbors as a “Johnny Come Lately” who was trying to buy his way into “higher society”.

    All my earlier treks off the beaten path, so to speak, were because I had not long before finished reading Vanora Bennett’s excellent book (maps, websites and all): “Portrait of an Unknown Woman”. Many references to times and places for Sir Thomas More and his family.

  36. bdid1dr on April 19, 2012 at 5:30 pm said:

    What I’ve been trying to point out is that Nick promised the person who presented this “puzzle” to him to preserve his anonymity.

    Fact: Greenwich University’s “Mansion” Campus IS what was left of Col. North’s Mansion. After North’s death, the mansion was a college for teaching young women to become teachers. The mansion/school was damaged during the “Blitz”.

    It was eventually purchased by Greenwich University. There are still several artifacts of the original owner “here and there” on-campus.

  37. Milen on July 11, 2012 at 12:27 am said:

    Hey guys,

    since I’m studying Hindi, I can’t help notice that several of the symbols are the same in the Devanagari alphabet, C, P, and M especially.

    Hope this proves interesting 🙂

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  41. mutter oberin on July 8, 2013 at 7:24 pm said:

    it’s an alchemist script, probably with kabbalistic connections. i can’t decypher it, but i’ve seen various scripts that style over the years, most dating back in the days of john dee.


  42. eddie hasan on August 23, 2013 at 6:11 pm said:

    so if i want to write some thing with this blitz ciphers …according to ur conversion to the english alphabets will it be meaningful ?

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  45. Dragonfly on September 9, 2015 at 2:41 pm said:

    As Milen also recognized, some of the cyphers/charactes show familiarity with characters of the Devanagari alphabet which is used for Hindi.

  46. Rick A. Roberts on December 1, 2015 at 7:42 am said:

    This is in regards to Page # 1 of the Blitz Ciphers. I was recently looking at this page, and noticed that Page # 1 has the letters, ” CM ” in the center of it within concentric circles at the top of the page. I was looking at a story about Jakub Krocinek, an astrologer and his two sons. Krocinek was Rudolf’s Astrologer. His younger son killed his older son to obtain an alchemical treasure that was hidden in the walls of Faust’s House. Rudolf lived in the Faust House and he invited many people who had similar interests as he did to visit. He invited Dr. John Dee to visit him. Dr. Dee had written Mercurius Coelestis(Celestial mercury) in 1549. It was a twenty-four volume work that was lost. Could the Blitz Ciphers be the Mercurius Coelestis(Celestial Mercury) Works that was written by Dr. JohnDee ? He was highly influenced by the Rosicrucians.

  47. Rick: Dee died in England in 1608 while the Rosicrucian manifestoes were written in Germany largely after his death… so it seems unlikely that Dee was influenced by the Rosicrucians. Having said that, they do make prominent use of one of Dee’s emblems, so it does seem that their authors at least wanted them to look as though they were influenced by him. 😉

  48. Sionainne McCreesh on November 8, 2016 at 12:32 am said:

    Has anyone tried deciphering the Theban and Ogham that are on here?

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