Category Archives: Ww2 Cipher Pigeon

Previous posts here have established (I believe) that the WW2 Pigeon Cipher was almost certainly encrypted using the British Typex cipher machine. So I think it would be a good idea to look at this message from a Typex code-breaker’s point of view.

While Kelly Chang’s (2012) master’s project on the cryptanalysis of Typex is a very useful resource here, I think it’s fair to say that she confines her efforts to purely numerical, permutational attacks. But because she doesn’t try to peer inside an actual ciphertext, I think it’s also fair to say that she doesn’t really look at Typex from a practical code-breaker’s perspective.

So, let’s get to it: let’s (temporarily) close our mathematical eyes, and instead try to look at a Typex message (the WW2 pigeon cipher) through our code-breaking eyes.

The Typex Keyboard

Whereas Enigma was just 26 plain letters A-to-Z (no numbers, no spaces, no umlauts, and not even a special Swastika symbol), Typex had two modes: Letter Mode and Figure Mode. And so the Typex keyboard (below image from Crypto Museum, or you can play with a real-looking one at Virtual Typex) encodes lots of letters in slightly roundabout ways (akin to escape code sequences).

The most notable mappings in Typex’s (default) Letter Mode are:

• X –> Space
• V –> Switch to Figure Mode
• Z –> Switch to Letter Mode

In Typex’s Figure Mode, the top row maps to numbers (QWERTYUIOP —> 1234567890), the second row (largely) maps to punctuation symbols, while the special Letter Mode meta-letters (X/V/Z) maps to G/C/D.

So, to encipher “X” on a Typex keyboard, you’d need to switch into Figure Mode (“V”), press the Figure Mode version of the letter (“G”) and then switch back into Letter Mode (“Z”), i.e. “VGZ”.

Putting this all together, you can see that before sending the classic test sequence “The Quick Brown Fox Jumps Over The Lazy Dog” via Typex, you’d need to “escape” the letters to the Typex keyboard mapping, i.e.

THEXQUICKXBROWNXFOVGZXJUMPSXOVCZERXTHEXLAVDZYXDOG

Here, I’ve highlighted the three escape sequences (for “X”, “V”, and “Z” respectively): similarly, 1234567890 would need to be Typex-escaped as “VQWERTYUIOPZ” before transmission.

Was Typex’s keyboard a strength or a weakness? Certainly, it was more sophisticated, and gave more a concise, bureaucratic feel to messages (“£2/3/6” would have been vastly longer for Enigma). But at the same time, the added expense and physical complexity (the number of Typex machines built was only ever a fraction of the number of Enigma machines in use) seems fairly unwise to me.

Moreover, Typex’s keyboard’s escape sequences significantly modified the way technical language was transmitted. Even though shorter messages are harder to crack than longer messages, I can’t help but wonder whether Typex’s escape sequences might have added crypto weaknesses.

Typex “X”

Any enciphering system that enciphered spaces as X would instantly make X the most common letter in (escaped) plaintexts. So it should be clear that Typex’s letter “X” (which enciphers SPACE) was one possible weakness.

Moreover, right from the earliest part of the war, German codebreakers noted that the first three letters in a new class of intercepted messages were never “A”, “I”, and “R” (respectively), and the last letter was almost never “X”. From this they deduced (correctly) that:

• Messages were being sent using an Enigma-style rotor cipher machine (where letters never map to themselves)
• The sender was almost certainly the British Air Force (“AIR”)
• The last letter was probably using X as a padding character

Even if Typex is (largely) randomising the output letters (via permutation and stepping), we still know that plaintext “X” can never be enciphered as ciphertext “X”. Can we use this to look inside the ciphertext?

If we discard the (almost certainly disguised) rotor setting AOAKN at the start and end of the pigeon cipher message, we get the following:

      HVPKD FNFJW YIDDC
RQXSR DJHFP GOVFN MIAPX
PABUZ WYYNP CMPNW HJRZH
NLXKG MEMKK ONOIB AKEEQ
UAOTA RBQRH DJOFM TPZEH
LKXGH RGGHT JRZCQ FNKTQ
KLDTS GQIRU

For this 25 x 5 = 125-character ciphertext, a completely random letter mapping would imply an average instance count of (125/26) = 4.8 instances. In fact, the instance counts of the letters (in decreasing count order) are:

H K R N P D F G Q A J M O T E I X Z B C L U W Y S V
8 8 8 7 7 6 6 6 6 5 5 5 5 5 4 4 4 4 3 3 3 3 3 3 2 2

Even if X is the most common letter in the plaintext, the amount of enciphered text would need to be very long (I’d guess 20+ times longer or more) before Typex (escaped space) X’s higher frequency would show up as a measurable dip in the (Typex ciphertext) X’s statistics.

X:    ----- ----- -----
--X-- ----- ----- ----X
----- ----- ----- -----
--X-- ----- ----- -----
----- ----- ----- -----
--X-- ----- ----- -----
----- -----

Sadly, because of the short length of the ciphertext, the only thing to note is that the third and fifth lines have no X’s in, which we’ll return to in the next section.

Typex “Q”

From the preceding table, we can see that Q appears six times in the ciphertext. Even though Q is a relatively rare letter in English (hence 10 points in Scrabble), there are a number of different ways that Q can practically appear in an enciphered Typex messages:

• As the letter Q in text (in Letter Mode)
• As the digit 1 (in Figure Mode)
• As part of a five-letter QQQQQ separator block (these appeared in the middle of Typex messages, and were used to help conceal messages starts e.g. coded addressees)
• As a null (Typex operators were, as part of the security protocol, expected to insert a random character every few words)
• As part of a Q-code

Even though Q-codes were originally used for shipping transmissions, their use quickly spread through the various armed services. A few years ago, I found a Combined Operating Signals handbook in the Royal Signals Museum archives. Its first page looked like this:

But though it is entirely plausible that a WW2-era message might include Q-codes such as QPZ (“Yes”) or QQZ (“No”), my understanding is that Q-codes were far more for radio operators than for cipher machine operators. Hence I’m not genuinely expecting to find any Q-codes in the plaintext here.

I’ve previously posted about QQQQQ here, but the short version is that if we look at the six instances of Q that appear in the pigeon cipher message, they appear to cluster in the bottom half of the message:

      ----- ----- -----
-Q--- ----- ----- -----
----- ----- ----- -----
----- ----- ----- ----Q
----- --Q-- ----- -----
----- ----- ----Q ----Q
----- -Q---

Of course, this might just be a sign that randomness is doing its random thing here. But there’s a pretty good chance that the lack of Q’s in the top half implies that the top half of the plaintext has more Qs than normal.

Why might that be? The two most likely reasons would be (a) the presence of a QQQQQ section divider block (say, on the “PABUZ WYYNP…” line), and (b) the presence of number sequences (because in Figure Mode, Q enciphers the digit “1”). And because of Benford’s Law, we might reasonably expect “1” to appear more often than other digits, so this perhaps isn’t quite as arbitrary as you might at first think.

I also wonder the lack of Xs on the third line might be an indication that the block of five letters immediately before the (putative) QQQQQ ends with a block of Xs, e.g. –XXX QQQQQ. It’s certainly possible…

Other Letters

If we look at the five Ts in the ciphertext, these too cluster at the bottom in a slightly unusual way:

T:    ----- ----- -----
----- ----- ----- -----
----- ----- ----- -----
----- ----- ----- -----
---T- ----- ----- T----
----- ----T ----- ---T-
---T- -----

And the two Vs in the ciphertext are also (perhaps) notable for both being at the top:

V:    -V--- ----- -----
----- ----- --V-- -----
----- ----- ----- -----
----- ----- ----- -----
----- ----- ----- -----
----- ----- ----- -----
----- -----

Note also that even though the instance counts of V and Z in any given message will (almost certainly) be identical (because Figure Shift will be followed by a matching Letter Shift back again), these are small enough that they won’t show up in the instance stats. But the small number of Vs in the ciphertext might possibly be a (very weak) indication that the bottom half of the text has a lot of Figure Shifting going on.

But really: are these statistically significant results, or is it merely the Randomness Fairy laughing into her hand? A researcher with the persistence of Dave Oranchak would randomise millions of cases and see how often these conditions recur: but with such a small ciphertext, it’s hard to be sure. For now, though, it’s just a set of interesting observations. 🙂

I missed Virtual Typex‘s launch back in March 2020, but a Cipher Mysteries review is better late than never, eh?

The short version: Virtual Typex is a gloriously techy bit of onscreen kit, that simulates all the moving components of a Typex cipher machine in a visually satisfying way. You’ll need a big monitor to see all the details properly (think UHD rather than HD), but as cipher machine simulations go it’s really nice-looking. (Though see the final section below for the caveat.)

There’s an extensive set of help / introduction screens here, which both set the historical scene nicely and explain all the fiddly stuff to do with rotors, plugboards, and reflectors (and how Virtual Typex simulates them all). They don’t include any real Typex rotors (or rotor insert) settings, which is a huge shame (but I’m sure that Cipher Mysteries readers already knew that GCHQ aren’t likely to release anytime soon, bless ’em).

One nice piece of Typex history they got right (which I think may well be described here for the first time) is the wiring for the basic Typex reflector. This they managed to infer from an engineer’s Typex Mk III rotor-test cheat sheet when used with the pass-through rotor insert test set (and with the “DRUMS LOCKED AT AAAAA”:

The discussion on the page continues:

[…] it is therefore possible to work out the reflector wiring for Typex as the [pass-through] rotors add nothing to the cipher in this case.

To do this, you’ll need one more piece of information, how the input & reflector heads (the connectors on either side of the rotors) are wired. The diagram above shows that on Typex, the input was wired reversed with respect to the reflector. This means that while A input pin is in line with the A reflector pin, B sits opposite Z, C-Y, D-X .. Z-B.

This, satisfyingly, then yields a Typex reflector mapping of:

As I said above, this is a really fantastic visualisation tool, that lets anyone who wants to try out a Typex for themselves (but without investing their pension on buying their own Mark 22 at auction, *sigh*).

However, it might not be correct. 🙁

Much as I like all the visuals and interactive side of VT, I’m going to be a huge spoilsport by suggesting as nicely as I can that I don’t think that this hasn’t yet been verified against a real Typex: and that anyone who relies on this as an actual simulation might well come a cropper. 🙁

The reason I think it’s incorrect is that if you (virtually) put any of the rotors with inserts in, and enter A twenty-six times (i.e. enough to rotate the first of the moving three rotors through a complete revolution), the next rotor along only clicks over five times (in an Enigma, it would click over once). Here’s the sequence of rotor settings you see onscreen in Virtual Typex:

• AAAAA
• AABAA
• AACAA
• AADAA
• AAEAA
• ABFAA <– i..e. the first time the second rotor along clicks over
• ABGAA
• ABHAA
• ABIAA
• ABJAA
• ABKAA
• ABLAA
• ACMAA<– the second time
• ACNAA
• ACOAA
• ACPAA
• ACQAA
• ACRAA
• ADSAA <– the third time
• ADTAA
• ADUAA
• ADVAA
• ADWAA
• ADXAA
• ADYAA
• AEZAA <– the fourth time
• BFAAA <– the fifth time

To my eyes, the problem is that the standard-issue empty rotor (i.e. the empty rotor that the inserts insert into) has nine triangular notches around its outside, not five. And it was my best understanding that it was these triangular notches that trigger the rotation in the next rotor along.

It’s always possible that I’ve got this basic physical detail wrong, but it’s certainly something that I’d like solidly checked before endorsing Virtual Typex as anything apart from beautiful cryptographical eye candy. :-/

PS: I also couldn’t help but get the impression that parts of the site’s historical documentation had been lifted unattributed from Cipher Mysteries, which is a bit cheeky. Just thought I’d say, hohum. :-/

Because Trove holds newspaper articles all the way up to 1954, you occasionally stumble across interesting stories from around the world picked up by Australian newspapers. And because I’ve been raking over the various editions of the Truth, my virtual path has recently been littered with such things (though admittedly slightly racier and more gossipy than the dear old Adelaide ‘Tizer).

We surely all know about the Somerton Man: so here’s a link to the Truth’s take on the story, including this photo:

Another mysterious man was found near a beach on 2nd July 1949 (said the Truth elsewhere). However, this quickly turned out to be 23-year-old ex-soldier David John Wicks. He had been working as a yardsman at the Pineapple Hotel on Kangaroo Point: it seemed likely he had died as a result of having previously contracted malaria. Doubtless people will construct conspiracy stories around Kangaroo Point (which has appeared a fair few times here). *sigh*

Much more recently, yet another mysterious man found at Poona Dam at Nambour, 9th September 2008: “apart from the smiley face message, the only other thing in his wallet was an old Plains Video Kingaroy rental card.” A reconstructed picture of his face looked like this:

Again, a possible breakthrough was made earlier this year, when a man came forward to report that his brother Charles Rawlins was missing:

But what about the pigeon, Nick?

Ah, yes, sorry about that. The Truth related the tale of a pigeon-based cipher mystery so straightforwardly that it would be churlish not to quote it in full:

The Brisbane Truth 28th September 1952, p.34

ALL DUTCH TO EXPERTS

LONDON, Sat.— A carrier pigeon landed on the deck of an American cruiser during the recent ‘Exercise Mainbrace,’ the North Atlantic Treaty Powers’ manoeuvres. It bore a peculiar message.
No cyphers could be found to fit it. So the captain decided to rush it to headquarters. There, code experts got to work on it.
After seven hours it remained unbroken. It was a perfect code. Code breaking machines were put to work on it — no result!
Then it came into the hands of a Scottish sub-lieutenant: ‘It’s written in Gaelic,’ he pronounced.

A few years ago, while giving a talk at Westminster Under School on the WW2 pigeon cipher, I mentioned that (a) Typex messages were sent in groups of five letters; and (b) when some German codebreakers looked at intercepted Typex messages early on in the war, they noticed that the last letter of each cryptogram was almost never X.

I then asked the Westminster boys what the Germans inferred from this (which was actually an incredibly subtle and difficult question). I was thoroughly delighted when a quiet high voice at the back suggested that the Germans could have concluded that they were looking at an Enigma-class machine encryption, where the last letter group was padded out with Xs.

Indeed, our young future head of GCHQ was right: the space bar on the Typex keyboard was attached to the X key, and operators typically used spaces (i.e. Xs) to pad out the final message group to a multiple of five letters.

Separately, German codebreaker Otto Buggisch also noticed early on in the war that the first three letters of RAF Typex messages were almost never A, I, and R respectively: though Buggisch deemed his obervation to have “no practical significance”.

All the same, this is a good example of bad enciphering practice (because stereotyped contents such as HEILHITLER or KEINEBESONDERENEREIGNISSE leave all cipher systems exposed), and goes to show that Britain started the war with cipher practices that were essentially no better or worse than Germany’s.

Yet if we have a look at the secret history of the QQQQQ group as used in Typex messages, we find something that might help us to (eventually) reveal the contents of a well-known cipher mystery…

The British Navy and Typex

ADM 1-27186 tells us in good detail how Typex cipher practice changed in the British Navy through the war years.

The Navy started with the same set of five black rotors used by the Army: the machine setting keys specified which drums to use, and were initially constant for a week, but on 2nd September 1940 were changed every day. A further two red rotors were added on 1st June 1941, giving a choice of seven rotors.

At first, the per-message drum settings were chosen at random by the operator and “the actual initial setting of the drums was transmitted as the first and last groups of the message or message section”. “Message sections were limited, for security reasons, to 60-70 groups, after which a new message section was chosen. Sections were separated by groups of five Q’s.”

Hence the first appearance of QQQQQ in Naval Typex messages was as a plaintext separator between message sections. That is, a typical long message would look as follows, where ABCDE was the (raw) indicator of the first message section and LMNOP was the (raw) indicator of the second message section:

ABCDE ….. [60+ groups] ….. ABCDE QQQQQ LMNOP ….. [more groups] ….. LMNOP

Buggisch also recalled that some Typex-related documents found at Dunkirk (along with a rotor-less Typex machine, and perhaps a reflector) mentioned “an English cipher security officer point[ing] out that he has noticed frequent breaches of the strict regulation that wheels should be turned on at random after a message has been enciphered”.

On 1st November 1941, however, Navy operators’ freedom to choose their own settings was curtailed, and books of disguised message settings were introduced in the Navy: at the same time, the practice of using QQQQQ as a section separator ceased.

After 1st March 1942, the optional use of Typex plugboards was indicated by FIELD at the start of messages.

1st February 1943 saw the introduction of two sets of seven new rotors wired specifically for the Navy, called “Code X” (for normal secure traffic) and “Cypher X” (for more secure traffic with plugboards), and where the original seven drums were still used for Inter-service traffic. Then:

On the 29th December, 1943, following a further review of Typex security, which amongst other things showed this system was particularly vulnerable to cryptographic attack from stereotyped beginnings, a revised procedure for concealing the start of the text was brought into force. From this date, the first ten to fifteen words of the subject matter were buried in the text, in addition to the address.

A new (and somewhat cumbersome) doubly-enciphered message setting procedure was introduced on 1st February 1944: but this was broadly balanced out by extra latitude when dealing with multiple message sections. Now “message sections were once again distinguished by the self-evidence group of five Q’s with the added proviso, however, that after each such group the right hand drum must be rotated one place before encyphering was continued.”

Finally:

In April 1944, the cyclic procedure was introduced as a security measure in the cyphering of short messages which, by reason of their brevity, were unsuited to the “buried address” procedure.

I don’t know what “the cyclic procedure” was, all suggestions gratefully received. 🙂

The British Army and Typex

Christos has a good page on the Typex, with scans of HW 40/89: ‘Typex questionnaire’:

From this, we know that at the very start of the war, each Typex rotor contained 14 “large” letters (of 26), where operator-set random settings could only use these large letters: but this restriction disappeared in mid-1940.

Codress burying (i.e. concealed coded addresses) was introduced on 1st January 1941, while disguised message settings were introduced on 19th May 1941, some six months before the Navy did the same.

A letter-shift procedure was introduced on 1st Feb 1944, and a figure/letter shift procedure on 1st September 1944: these were introduced in the Navy on the same dates.

The Royal Air Force and Typex

It was the RAF who invented Typex: but the amount of RAF-related Typex information I have found is quite small.

However, Stuart Rutter once posted some scans (now only in the Wayback Machine) from the February 1943 user manual for the (mostly) portable Typex Mk VI (which is what I suspect was used in the field for the Pigeon Cipher):

Preparation of message for transmission – Withdraw and detach the tape from the message printer and insert in manuscript, as the first group, the disguised message setting used at the commencement of the message. If the message is complete in one section write this disguised message setting and groups of five Q’s must be inserted appropriately in the spaces left for that purpose. Each section must begin and end with the disguised message setting, in manuscript, appropriate to it. The tape should then be gummed to a message form so that there are ten groups in each line. This is done in order to facilitate the counting of the total number of groups.

It’s not as clear as in the other cases how the QQQQQ section should be used, but it’s there nonetheless.

Can Love Conquer All?

Dufty recounts (chapter 43) a charming “cryptological love story” about two lovelorn Typex operators separated by General McArthur’s push North, who would occasionally hide messages to each other at the start of Typex messages.

The way they had been trained to use Typex was to write some filler nonsense text at the start (presumably the “ten to fifteen words” mentioned in the Navy account), followed by an (enciphered) QQQQQ separator, followed by the address and finally the actual message contents. Because the filler text was stripped out of the message at the far end before being passed onwards, the operators had just enough latitude to insert their own messages.

Incidentally, it’s not clear to me whether this QQQQQ was always added at a five-letter boundary or whether it could appear at any position: I strongly suspect the former, so it could prove valuable to find out from any still-living Typex operators if this is correct. (Perhaps I’ll ask David Dufty if he would be so kind as to ask one of the Australian Typex operators he interviewed.)

The reason this might be interesting to us is that if (as has seemed reasonably likely to me for some time) the Pigeon Cipher was sent on D-Day (6th June 1944), their Australian love messages in the margins were being sent at about the same time.

And so it may well be that the Pigeon Cipher’s internal structure includes a short filler section and a (plaintext) QQQQQ block, followed by a single extra step on the rightmost rotor: and only then the actual message.

Cryptanalyzing QQQQQ?

The introduction of a filler header plus a QQQQQ separator to Typex messages certainly had the effect of hiding stereotyped beginnings, which was a positive lesson learned from attacking Enigma.

Yet had German cryptanalysts had a reflector and a set of Typex rotors to work with (which they very nearly did on a number of occasions, most notably in Dunkirk and in Tobruk, and there was even a “North African Story” that claimed that they did), could they have exploited (later in the war) the presence of plaintext QQQQQ to crack messages, perhaps with some Bombe-like machine assistance?

Kelly Chang’s (2012) dissertation on the cryptanalysis of Typex is silent on this: Chang treats Typex messages as if they were flat, uniform text messages (i.e. ‘pure’ Typex), which – as we can see from all the above – they were often not.

So, if a Typex message contains plaintext QQQQQ, where would it be? A first trick is to note that because we also know that Q cannot encipher to itself on both Enigma and Typex machines, we need not search for QQQQQ anywhere in a Typex message where Q appears: that is, we can sometimes see where QQQQQ isn’t. And if it turns out that the practice was to only place QQQQQ on five-letter boundaries in the plaintext, we need not check any ciphertext block containing a Q.

Furthermore, given a day’s collection of intercepted Typex messages (which would all have the same rotors selected), a German codebreaker could select the message with the most (random) instances of Q in the top part of the message, so as to sharply reduce the number of places to brute-force search for QQQQQ (because each Q instance in the ciphertext would ‘knock out’ itself and four preceding positions to check).

Curiously, in the case of the Pigeon Cipher, if we colour blue the five-letter indicator groups at the start and end, and colour red all the instances of the letter Q…

…you immediately notice that the third line (“PABUZ WYYNP …..”) contains no letter Q instances at all. This may just be a coincidence, of course: but I personally would be unsurprised if that line turned out to contain QQQQQ in the plaintext somewhere.

If this is right, do we now have enough to break the Pigeon Cipher? I’m not yet sure: but I suspect we’re starting to move closer to a position where we can reduce the search space by millions (if not billions) of times. And at some point, perhaps we’ll have reduced it enough to be able to sensibly set a search in motion… we shall see, fingers crossed!

Here in the UK, it all started with a story in 27th August 2015’s Daily Telegraph:-

Didac Sánchez, a 22-year-old Spanish IT entrepreneur, says he has deciphered Second World War message following a three-year effort at a cost of €1.5 million (£1.1m) – but won’t reveal its message.

Sánchez claims he told GCHQ of the message’s contents: but GCHQ (of course) denies all knowledge of it.

Now, I have to admit that this is quite a different angle from the media’s usual cipher mystery-related tosh. But what’s in it for Sánchez? Ah, the Telegraph went on to say:

He [Sánchez] now plans to market new security software based on the code, a system he has christened 4YEO (For Your Eyes Only) and which will allow any text, document, WhatsApp, Messenger, SMS or Skype conversation to be encrypted, as well as telephone calls.

And A Didac Sánchez Cryptogram Too…

And – mirabile dictu – Sánchez’s clever people have posted up a challenge cryptogram supposedly generated using 4YEO’s software, offering a bounty of 25,000 euros to the first person who can crack its “indecipherable” secrets before, errrm, 31st December 2015:

GDNFP IUALI ZOANN EEING DUORL IELTE ROMSO EVCIS AIFON NBNTN IEPSR LAAAT JELAE IMIRN RSNEP IADIA NIATD DPVRO RURLU UAELP RLASR AAOSQ PDSOY EMINL RIDLN NSIEA AEULA AFSTO DIIUF RRRCG EEZIS BAXTI MMORI ORANO FHDER DCNNT NRADA ETAER CDNIO EEAIO EROMT TUDVI AOCDS RHSEU RLALQ CCOCC MIEON NRNIT TOESF OAAMN ANTAO OICEJ TOSBD DEPIR OIANE AOZUE ECCCN IAEIS REECI IRNUR IATCE FSEUC EIENC ROASP COPSU LNUTI VOUES RACCR SYNCA MROIU TLJOB UVSOO JIRLE SSETU TNNOT ASRNE IOBCU NALEU OMEER GINOU AAETL STHER ONLAR ROTIE LENDR AEEYO TRSBR TDRTE HETRR ICUEL TRDCE ASNND TUCOD MDUJA OESPL RESEG OMOCL TAMTI IEGLM AAERR RRSEN SIBAI EICDL RILCE LOXES ELUEO CTANP TNRYU XGGTA NSTIO DSADC CDEER EODNA SAALS CCZEE EENRE LAOOR VASHA SLEAJ CAITE HRTER ELNIA GNTEL DSAAN EOFTD NURAD OSACE MDICR IOACT NEERO OATCA IRPAO NISMD SVECT NLYLT TETNS HSACL NETNL PGIEU EEEDL DCTSR PÑMDM ATUED OOSTS YERCD TRCAO ANAIE EPSNR ZMMCI RIDIL RIAGD IOMRI SAEAN VOLEE TBEOR OEEEA SEOEA EERAO OLSLM EAERO ZUHVU ALEEM EONIA AOEEZ CEEON NNESO ANBMI DLFDP LEIIS LQCMT UROIT SRAON EICLL IQCNL LIOIT RFAAN NDMTL ECESN OCOIL STOPA OACIS SAVCN ALARE EAIEC OSBNE OOHPS TSGLO LELDP MNGCM ORNUV LCLJG IINAM AOCAS TSOIL NNELA ONTEE OAAOU LIADO VNSEL RSQAM AOMOS CLVND IUREN TTEEA IIREE FOONN OORAP IYAAT ESLAI INPSO EVARO ARONE OÑNNA IGOSI ZPENA UIAAO LUEOA OERDH SVRTO MEOUI GADLR SDNIR BOESS NDTEA PEMFI LEAUI UEEOD OSSEO RLRDI ILBEU OOLTC NDTAE OSCMO OTASR SYDNO EMLMA EAEIR MIAAA IRUOR LESSC ROULE TARAN ASNÑT UNUDS EOTHC EBEGI OEDTG LOPAL LADAB DLISI SEDOE SRGDO OTODT AROAM CLCBE FDAEA HIAAI LARAE BIBEV AAMNO AIAAE POARO IIEEA EYSAF EEIEP RAGTE ANNOS OPLEA ACEDS IIIDA INZEA INNNC YYAEB EEEPI CENCU TNOSD URJIO LDESA LIITN ODIAI MEORE AEMUP EOCLE EOCAC AOC GDNFP

Things to note about this Sánchez challenge cryptogram:
* There are three 5-letter repeats (OTASR, RLESS, GDNFP), which I think would imply that this is not a simple substitution cipher.
* From the presence of “Ñ”, it seems that the plaintext is probably Spanish or Catalan [Catalan does not have a Ñ letter].
* The most common letters are EAOINRSLTC, whereas the most common letters for Spanish are EAOSNRILDT, and the most common letters for Catalan are EASRLTINOUM.
* Hence it seems that, completely unlike the WW2 pigeon cipher, this is nothing more than a path transposition cipher of a Spanish plaintext.
* The length (in characters) is 1428, which factorises as 2 x 2 x 3 x 7 x 17. [But see the update below!]
* Hence this might feasibly be formed from four sequential transposed blocks of 17 x 21 (or of 21 x 17) characters. [But see the update below!]
* Given that no algorithm is specified, it seems that the cryptogram maker is inexperienced in cryptography and hoping for “security by obscurity”.

Naturally, my normal 15% crypto-consultancy rate applies if you manage to crack it from this. 😉

What Does Nick Think?

What do I make of all this? Well, from all this I hear the clear guiding voice of someone who appears to know almost nothing about how encryption technology works in the real world of heterogenous networks and protocols: there could be no single ‘silver bullet’ that could satisfy the technological needs of encryption in all these areas simultaneously.

So all I can honestly see here is a fake from start to finish, a homegrown transposition cipher cobbled together by someone who has perhaps seen the Feynman Challenge Ciphers (but little else besides), and designed to hype some vapourware (i.e. software which hasn’t yet been written). Do I honestly believe that Sánchez’s allegedly crack team of, errm, code crackers ever existed, never mind cracked ‘our’ WW2 pigeon cipher? No, sorry, I don’t. I really don’t.

So unless anyone has proof otherwise, I call this entire story as a Big Fat Modern Bluff, someone trying to appropriate a real-life cipher mystery to promote some crypto-security vapourware that hasn’t even been written. Would I entrust my data to any company who thinks this is in any way “indecipherable”? No, I would not, sorry.

And this is exactly where I planned to finish the whole coverage of this story…

But Then I Read This…

According to this first part and this second part of detailed Spanish exposé from last September, courtesy of Madrid-based online political daily ‘El Confidencial’:

* Didac Sánchez is just a frontman for a group of companies
* Of those (at least) fifteen companies, only three have so far filed any accounts, with a total combined turnover of less than a million euros, some 2% of the amount claimed in the press.
* The journalists were unable to find any genuine trace of several of the other companies (e.g. Hilton Clinic), despite numerous promises made by Sánchez himself to supply them documentation on the companies’ activities.
* Sánchez’s original name was Diego Giménez Sánchez, but he changed it to Diego Sánchez Giménez
* Sánchez’s real history is to be found in connection with his original name (Diego Giménez Sánchez)
* On 29th May 2005, Diego Giménez Sánchez was (at the age of 12), while living in the Casal dels Infants del Raval in Barcelona, sexually abused by a 45-year-old man by the name of José María Hill Prados. José María Hill Prados was convicted in February 2007 (and banned from contacting Giménez Sánchez for five years or coming within 1000 metres of him), but later appealed, saying that Giménez Sánchez had withdrawn all the claims. However, the court was not swayed by this, or by Sánchez’s many letters (and even TV interviews) at the time. José María Hill Prados has since been released.
* Fast forward to 2015, and El Confidencial’s journalists discovered that the person actually behind all Didac Sánchez’s companies was none other than… José María Hill Prados, whom El Confidencial helpfully labels as “pederasta del Raval”.

Personally, I have no way of knowing what the truth of this matter is. At the very least, the existence of Sánchez / Hill Prados’s company ‘Eliminalia’ that helps people remove their unwanted past from the web is an aspect to this whole affair that is either horribly cynical or spectacularly ironic. Closets have rarely held more skeletons simultaneously, it would seem.

Make of all this what you will. 😐

Update: I just now noticed (*sigh*) the connection with the WW2 pigeon ciphertext – the first five-element code group (GDNFP) is the same as the last (GDNFP). In the case of the WW2 cipher, this is almost certainly because it encrypts the initial settings for the five drums used in the Typex machines used so much by the British Army: but in this challenge cipher, who knows? But this would probably make the length of the ciphertext either (by excluding the final GDNFP) 1423 (which would be a high unlikely message length for a transposition cipher, because it’s prime 🙂 ), or (by excluding both the first and final GDNFP) 1418 which equals 2 x 709, which is also somewhat unlikely as a transposition ciphertext length.

So what is probably going on is that “GDNFP” is encrypting some kind of reordering key to the transposition cipher. If A = 1, then (in ascending order) G = 7, D = 4, N = 14, F = 6, and P = 16. If an idiot programmer was behind this, one might possibly predict that this encodes a five-letter-long hex number (i.e. 0x63D5F = 408927) as the enciphering key. If an idiot mathematician was behind this, these might be indices into a list of prime numbers, A = 2, B = 3, C = 5, D = 7, E = 11, F = 13, G = 17, H = 19, I = 23, J = 29, K = 31, L = 37, M = 41, N = 43, O = 47, and P = 53, so [GDNFP] might instead encode [17,7,43,13,53]. Chances are that these are the kinds of thing this peasanty / homegrown transposition cipher will prove to use.

At a Westminster Under School Open Day not so long ago, I was delighted to find out from Miss Ellis (WUS’s Head of Mathematics) that after their final exams, Year 8 boys there spend time discovering the joys of cryptography and code-breaking: specifically, they go to Bletchley Park, find out about Enigma, and break some ciphers.

All the same, what with “The Imitation Game” and so forth, Nazi cryptography is at risk of becoming old hat (or do I mean alter Hut?). But what about Allied codes and ciphers? And – dare I ask it – what about that pesky WW2 cipher pigeon? Of course, once she found out that I knew about such wonderfully recondite (yet also historically and cryptologically rich) subjects, she set about trying to persuade me to give a presentation at the school.

What, me talk about Allied codes and ciphers, wartime pigeons, Typex machines, and D-Day history for two hours? (To be fair, I should perhaps say “for only two hours”.)

Needless to say, she didn’t have to twist my arm particularly hard. Or… at all, truth be told.

And so a few weeks ago, I pitched up at Westminster Under with a giant printout of the enciphered pigeon message, a 50-plus-slide Powerpoint presentation (heavy on nice photos, but light on text), and… a big empty space where I had originally hoped a Typex machine would be. (My cunning plan to borrow one from a friendly crypto collector fell through a few weeks beforehand, sadly. Oh well!)

To make the crypto side of the talk as ‘hands on’ as possible, I gave the boys a practical challenge using Double Transposition (The link is to a description I adapted from a genuine WW2 document Stu Rutter and I found at the National Archives in Kew.)

The boys divided into teams of three or four on a table, for each team to encipher secret messages for a different team to decipher (i.e. by supplying a pair of transposition keys with the message). Once they had got the hang of the technique, I set everyone the challenge of reliably enciphering the same short message at high speed: this was competitive and fun, yielding quite a nice balance of serotonin and adrenaline. 😉

In fact, there was a very specific Cipher Mysteries point to the exercise. Because we can tell that the cipher pigeon’s message was enciphered in only three minutes, we can deduce that it can only have been made using a machine cipher – nobody, I’m sure, could reliably encipher a message of that size in three minutes using Double Transposition, nor indeed with any of the other non-machine ciphers the Allies used in WW2. And Typex aside, the only other Allied machine cipher was the M-209, which had a ten-letter indicator (both the cipher pigeon message and Typex messages had five-letter indicators).

Incidentally, one nice crypto thing is that, having first gone through the history of the Typex machine, I decided to see how on the ball everyone was by throwing out a properly difficult crypto question to the audience:

Early in the war, German cryptanalysts noted that the probability of the letter ‘X’ appearing in the last 4 letters of a Typex message was extremely low. What did that tell them?

Naturally, when a boy (I didn’t get his name, sorry) at the far side called out the answer, I was hugely delighted, because many, many adults would not have reached that. (And so I leave it as an exercise for the reader, just as you’d expect).

As I’m sure will be no surprise, I thoroughly enjoyed myself – it was a great opportunity to give my cipher pigeon / Typex material a bit of a public airing – and I really hope that a fair few of the boys did too. They behaved in an exemplary manner, and were every bit as sharp, fast and engaged as I hoped they’d be. All credit to them for that, and a twenty-one gun salute to Miss Ellis not only for making it happen, but also for helping out on the tables for the Double Transposition exercise (which was very kind of her, and utterly necessary as it turned out).

Same again next year? I hope so! 🙂

PS: right at the end, one of the teams very kindly handed me a nice Double Transposition cipher challenge they had devised, which I thought I’d share with you here (I hope that’s OK with them). I’ve kept their original keys ( 😉 ) but modified their cipher only very slightly:

Sender: Strawberries & Cream
Primary Transposition Key: 9, 1, 10, 4, 2, 7, 6, 8, 3, 5
Secondary Transposition Key: 3, 1, 4, 5, 9, 2, 6, 8, 7, 10
Cipher Message:
SCCJL SRMTS SNJZH SCXFS VPTCT FSSLS XHZCS DVNQC
DHTKK TLSMT RKTSS FWSPW SNMZP XWVQM CZLKS X

Can you decipher it? Enjoy! 🙂

Here’s a lovely 50-minute film from 2005 for you about WWII pigeons (both English and German) called War of the Birds, made by Richard Cane for Atlantic Productions Ltd for Animal Planet. [IMDB page]

Though I knew about this ages ago, the link I had been given was to a compressed video that somehow managed to crash my various web browsers: but this new one works perfectly OK for me, so I’m happy to pass it on now. 🙂

As (almost) always with TV documentaries, it gets a fair few small details wrong (the pigeon message pad shown wasn’t a 418B, etc), but it gets enough big things right that this doesn’t really matter. The film even has Freddy Dyke (author of “Memoirs of a Wartime Teenager”, which I still haven’t been able to get a copy of) as one of its talking heads, complete with a properly resplendent moustache.

Recommended! 🙂

A quick recap: a copy of the WW2 cipher was placed on the leg of two pigeons, one with ring NURP 40 TW 194 and the other with ring NURP 37 DK 76. But we haven’t been able to identify either of these birds, or their owners, or even their clubs.

I recently suggested that NURP 37 DK 76 might have been owned by Mr L Duke of Great Shelford, and I continue to pursue that possibility. But just now, while speculatively browsing the (paywalled) British Newspaper Archive, I found a whole lot of stuff that was new to me…

Lost Pigeons

During WW2, Robert Lever of Ticehurst, Sussex placed a series of small ads in the Kent & Sussex Courier, offering sizeable rewards for lost racing pigeons (these were plainly no ordinary pigeons). And many of these had exactly the kind of NURP … TW pigeon rings we’re looking for:-

* Kent & Sussex Courier – Friday 29 November 1940, page 12
* Kent & Sussex Courier – Friday 06 December 1940, page 12

£1 REWARD, –LOST, RACING PIGEONS.
Ring Numbers NURP 39 NSC 62 (Black), NURP 40 TW 243 (Blue). — ROBERT LEVER, HIGHLANDS, TICEHURST

* Kent & Sussex Courier – Friday 14 February 1941, page 10

LOST–£1 REWARD–RACING PIGEONS.
Black Hen, NURP 39 NSC 62. Blue Cock, NURP 40 TW 243. Blue Chequer Pied Hen, NURP 40 HBC 182. Red Chequer Cock, NURP 40 W 4323.–ROBERT LEVER, HIGHLANDS, TICEHURST.

* Kent & Sussex Courier – Friday 13 June 1941, page 8
* Kent & Sussex Courier – Friday 20 June 1941, page 8

LOST, RACING PIGEONS ; 10s REWARD.–
Red Chequer Hen, NURP 39 JWS 31; Dark Blue Chequer, NURP 41 TW 5; Blue NURP 41 TW 14; Blue Chequer, NURP 41 TW 22.–Robert Lever, Highlands, Ticehurst, Sussex.

* Kent & Sussex Courier – Friday 22 May 1942, page 8

£1 REWARD.–Racing Pigeons, NURP 39 JWS, 119 (Blue); NURP 39, NSC 17 (Black Pied); NURP 39, NSC 8 (Black); NURP 41, TW 25 (Light Blue Chequer). –Lever, Highlands, Ticehurst.

Lever’s Pigeons

There are lots more local newspaper references to Robert Lever’s pigeons in wartime races:

* Kent & Sussex Courier – Friday 05 September 1941, page 5

TUNBRIDGE WELLS NEWS

PIGEON RACING.–The final young bird race was flown on Saturday from Tavistock (197 miles) under good weather conditions. Result: Sargent (Lewes) 1160, 1158; Lever (Ticehurst) 1159, 1157, 1154, 1152; Bristow (Lewes), 1106; Mrs Oswald Smith, 1078, 1077; Hills, 882. Mr Hills wins the “Frank Simms” young bird average cup : runner-up, Mrs Oswald-Smith.

* Kent & Sussex Courier – Friday 28 August 1942, page 5

TUNBRIDGE WELLS NEWS

PIGEON RACING CLUB.–The young birds racing from Dorchester (122 miles) for the first time attained a speed of 48 miles per hour. Liberated at 11.35 a.m., members were clocking-in arrivals from 2 p.m. Result : Henshall, 1443 ; Simms 1434; Carter, 1423; Ransom and Coleman, 1417; Mrs Oswald-Smith, 1407; Booth, 1385; R. Lever, 1326 ; Westow, 1295 ; Hills, 1293.

* Kent & Sussex Courier – Friday 28 May 1943, page 5

TUNBRIDGE WELLS NEWS

PIGEON RACING.–On Saturday, the race birds experienced a hard fly from Selby. Mr R. Lever, Ticehurst, timed in the winning bird, which flew the distance of 199 miles in 5 hours 47 minutes. […]

* Kent & Sussex Courier – Friday 26 May 1944, page 5

TUNBRIDGE WELLS NEWS

PIGEON RACING.–On Saturday, members raced their birds from Selby (191 miles). Liberation took place at 12.30 p.m., and birds were being clocked-in from 4.30pm, the leading ones putting up a speed of 45 miles per hour. Result: Lever, 1365, 1354.2 ; […]

…and again for Friday 9th June 1944, when Mr Lever’s pigeons were racing from Morpeth (290 miles).

Tunbridge Wells Racing Pigeon Club at War

Unsurprisingly from the above, Mr Lever’s local club was Tunbridge Wells Racing Pigeon Club: which was, far from coincidentally, pretty much my first guess as to the likely location.

Nicely, though, the Kent & Sussex Courier also included a number of short pieces from the same club that help us see the larger picture about pigeons in wartime. It may be a bit TL;DR for some, sure, but I rather like it all, and I get to choose what gets included. 🙂

* Kent & Sussex Courier – Friday 28 February 1941, page 6

TUNBRIDGE WELLS RACING PIGEON CLUB

At the invitation of the President (Mr W. C. Raiswell) and Mrs. Raiswell, members partook of tea, followed by discourse on club matters which are affected by war conditions, at their residence, Halls Hole, Forest-road, on Saturday. Amongst others who attended were Dr. and Mrs. Oswald Smith. Mr. H. Wallace Stubbs (Crowborough), Mr. T. Ashdown and Mr. A. Ransom (Chairman). Letters of apology for absence were read from Major J. G. Hiley, Messrs. H. Ashby and J. F. Mitchell. Corpl. W. J. Muddle, late loft manager to Mr. Raiswell, who is serving with the Royal Air Force, wrote referring to the valuable work the racing pigeons were doing in the R.A.F.

The PRESIDENT expressed regret at the unavoidable absence of Major Hiley, who is in command of a section of the Carrier Pigeon Service, and stressed the fact of how little was known of this essential war effort members were doing for the Services. The cost of breeding and training the right type of bird for strenuous flying was high. Unfortunately, many were shot or injured when on Service flights. Mr Raiswell thought the difficulty of overcoming the shortage pigeon food was not insurmountable, and he hoped that members would not let that obstacle deter them or reduce their stock, as the Army required every serviceable pigeon. He hoped the Club would not disband for the duration of war.

Mrs. Oswald Smith presented the following cups to the winners: Raiswell Cup for the best old bird average, F. Simms, average velocity 1,028 yards per minute over 10 races; “Robert Lever” Cup for bird winning the longest distance race (Fraserburgh, 462 miles), F. Simms; “Frank Simms” Cup for best young bird average, F. Carter, with an average of 1,136 yards per minute over four races.

The SECRETARY (C. R. Suffolk) gave brief report on the finances and equipment of the Club, which were in sound condition. Commenting on the possibilities of racing this season, he said much depended upon the conditions of rail transport. Apart from that he saw no reason why races should not be flown. He expressed his thanks to the Chairman and Mr. F. Simms for their valuable assistance setting and checking clocks and preparing racing panniers for despatch of birds; also to Mr. H. Colebrook for providing a trunk for storage of clocks and other equipment.

The CHAIRMAN, replying, said it was a pleasure to both himself and Mr. Simms to help the Club in every possible way. A cordial vote of thanks was passed to Mr. and Mrs. W. C. Raiswell for entertaining the members; also to Mrs. Oswald Smith for presenting the cups.

* Kent & Sussex Courier – Friday 06 November 1942, page 6

RACING PIGEON CLUB

Presentation to Mr. C. R. Suffolk

Describing what was perhaps the finest five minutes of his life, Councillor W. C. Raiswell recalled the indescribable thrill of pigeon racing and the intense exitement of waiting for and seeing the birds return to their loft after being on the wing for many hours.

The occasion was meeting on the 21st anniversary of the Tunbridge Wells Racing Pigeon Club, held at “Little Bredbury,” Tunbridge Wells, by kind invitation of Dr. and Mrs. H. Oswald-Smith, when prizes for the 1942 season were distributed and presentation was made to the secretary, Mr. C. R. Suffolk.

After report by Mr. SUFFOLK on the year’s programme, which had been most satisfactory despite wartime limitations, Mr. RAISWELL briefly reviewed the past 21 years. He recalled the old days when they had only two clocks for recording the return of the birds and a system wiring in was used. One member, he said, who had had a loft over a shop in Calverley-road, used to throw out of his window message to a boy waiting below, who would then wire in the time of the pigeon’s arrival. Later, when had installed a clock on the lawn at his house, he recollected members rushing madly down the hill on bicycles eager to “clock in.”

The President went on to speak of the vital work of what he considered to be the most important club in Tunbridge Wells. It was now stronger than it had ever been, and every member was really doing a great public service. Not only could pigeons be relied upon as valuable inland messengers, but they could be and were being used in co-operation with the R.A.F. and Royal Navy. Already they had been instrumental saving the life of Service personnel, though the full story of their achievements in that direction could not be told until after the war. Had the Club not been formed it would not have been possible to help in the national effort, and therefore grateful thanks were due to Mr. Suffolk, who had been Secretary from the beginning. “I have been requested by the members the Club,” concluded Mr. Raiswell, addressing the Secretary, “to ask you to accept something in recognition of the service you have given for so many years; a token of gratitude and appreciation what you have done.” He handed a cheque to Mr. Suffolk.

In reply. Mr. SUFFOLK expressed his thanks. Remarking that bis association with pigeons had commenced many years ago, when he had bought pair of birds for his small daughter. Mr. Suffolk told how suddenly he bad found hlmsAf Secretary of the Club, and later Federation Secretary when the Club had Joined the South Coast Federation He was able to bring to mind many interesting and amusing incidents in this all-absorbing sport, and how untiring enthusiasm had been rewarded by one of the greatest thrills, the thrill of seeing bird drop on to the loft after, a 500-mlle race. Unable now, for health reasons, to take part in actual racing, Mr. Suffolk said bow much he as Secretary enjoyed working out the times and velocities of the birds, details which required minute calculations. Mr. Suffolk hoped the Club would be enlarged after the war. and was particularly glad to note the ardent enthusiasm displayed by the Club’s youngest member, 13½-year-old Ernest Colebrooke. Finally, his special thanks went to Mr. Raiswell, Mr. Ransom and Mr. Simms for their constant support and co-operation.

Commenting upon a particularly successful season, Mr. RANSOM remarked that members were definitely improving, since all those who had raced had won a prize. One other presentation was to have taken place, that of a water-colour painting of his favourite pigeon to Mr. F. Simms in recognition of his untiring work on behalf of the Club, but unfortunately that gentleman was unable to be present. This remarkable piece of work had been painted by Mr. Suffolk, whose artistic invitation cards had also been greatly admired by all members.

For their charming hospitality a hearty vote of thanks was passed to Dr. and Mrs. Oswald-Smith, who at the close of the meeting miraculously produced a most Inviting tea.

Prizes were distributed by Mrs. Raiswell follows: Mrs. A. Oswald- Smith, 3 firsts, 6 seconds, 1 third and special; R. Lever, 3 firsts, 3 seconds, thirds and 2 specials; F. Simms, 2 firsts, 2 seconds, 7 thirds and 2 specials; E. G. Hills, 2 firsts, 2 seconds, 2 thirds; W. Henshall, firsts, 2 seconds; A. J. Westow, 1 first; Ransom and Coleman, 1 second, 1 third; G. Amsden, 1 first; F. Carter, 1 second, 2 thirds; S. E. Booth, 1 third. Ralswell old bird average cup—Mrs. A. Oswald- Smlth with average velocity of 1,082 yards per minute over nine races. Frank Simms young bird average cup—W. Henshall. velocity 1,036 (seven races). “Robert Lever” cup for longest distance old bird race —H. Colebrooke and Son, velocity 993. Number of birds sent to race points, 613. Amount paid out in prize-money and specials: £24 4s.

* Kent & Sussex Courier – Friday 28 February May 1945, page 7

PIGEONS DID GOOD WORK

A thoughtful reminder of the Important part that pigeons have played in the war, particularly with the R.A.F., was that given by Messrs. W. C. Raiswell in one of their windows in Mount Pleasant. Alderman Raiswell is the President the Tunbridge Wells Racing Pigeon Club, exhibited on Tuesday and Wednesday 10 birds which have been on active service carrying important messages. One was used by the R.A.F. when a V1 site was located. A notice read “Our tribute to the pigeons and the members of the Tunbridge Wells Pigeon Club.” Also on view were some exceptionally fine photos of famous birds. The pigeons were loaned by Mrs. A. Oswald Smith, Mr. F. Simms, Mr. A. Ransome and Mr. W. Henshall.

As part of my preparations for a talk on the ‘cipher pigeon’ that I’ll be giving at Westminster Under School in a couple of months’ time, I’ve been making sure that there aren’t any books I should have read.

The one I’ve most wanted a copy of is “Memoirs of a Wartime Teenager” By Frederick Dyke: but this is out of print and out of reach, so I’d need to book a day at the British Library to have a look at it. Perhaps I’ll get a chance shortly.

However, I recently found another book that I knew instantly I had to have: “Pigeons in World War II” by W. H. Osman (presumably a relative of “the late Lt.-Col A[lfred] H[enry] Osman, CBE”, who wrote extensively about pigeons under the pen-name “Squills”).

Though having said that, it’s not so much a ‘book’ as a book-shaped database: firstly, of letters from top-ranking officials thanking the nation’s pigeon breeders and trainers for their outstanding effort in WWII; and secondly, of microstories describing individual pigeons’ contributions to the same war effort.

Cross-referencing and correlating these pigeony microstories does conjure up a number of slightly larger pigeon-related narratives. For example, it seems clear that many of the pigeons employed by the US Army in Normandy for D-Day were bred and trained in and around Plymouth.

Yet the question I particularly wanted to try to answer – of course – is if we can find out any more about the two wartime pigeons “NURP 40 TW 194” and “NURP 37 DK 76” who were apparently carrying the two copies of our mysterious (or if not ‘mysterious’ then certainly frustrating) enciphered message.

Even though single-letter NURP pigeons (e.g. “NURP.42.A.4708”, “Bred by N.P.S. member, H. R. Veal, Basingstoke, Hants”, and “Trained by R.A.F. Station, Gillingham”) had a fairly random geographic distribution, I think it’s fair to conclude that multi-letter NURP pigeons tended to have at least some method to their naming madness. For example, “TTT” always corresponded to a group of pigeon breeders and trainers in Ipswich: “WAC” corresponded to Walthamstow, “SBC” to Shepherd’s Bush, “DX” to Doncaster, “WMK” to West Malling, and so forth. Additionally, many three-letter sets beginning with N– were from Nottingham, while many three-letter sets beginning with P– were from Plymouth. Just to keep you on your toes, it turns out that “XEB” was from Bexleyheath / Welling in Kent.

At the same time, there were also a fair few exceptions with no obvious rationale (“BFF” was from Poole, etc), so there was no universal naming convention, and hence we must tread carefully with our heavy-booted inferences.

The nearest to our DK and TW letter-groups was “RP.40.DUK.57” (p.116), a pigeon from an unnamed Thames Estuary breeder that was liberated in France on D-Day (i.e. the pigeon was liberated, not the breeder *sigh*), but who didn’t get home until the 8th of the following month. There was nothing remotely like the “TW” group to be seen.

I then checked this against the Special Section pigeon archive I had previously photographed at Bletchley Park (just to be sure), but that had no additional information (on its p.47) beyond what I’d just found:-

However… when I double-checked this against the list of owners in the Thames Estuary Group, one name in particular stood out like a severed thumb (guess who was just reading Conan Doyle’s “The Engineer’s Thumb” with his son?!):

So: my current best guess is that of our two pigeons, the “DK” one may well have been owned by L. Duke of The Stores, Great Shelford, Cambridgeshire – so I’m now following this up, and will see where it leads.

At the same time, another owner from the same Thames Estuary Group was W. H. Twigg of 71 Stevenson Avenue, Tilbury. Might it be that the “TW” was short for “Twigg”? It’s entirely possible (but still a bit of a long shot).

Hopefully, we shall see before too long…