Here’s a strange cipher device: the front-side is a medal depicting St. George fighting a dragon, the rear-side is a cipher disk. Does a reader know anything about the background of this item?

“Now I know what crypto currency really means”, my friend and blog reader Karsten Hansky wrote in an email he sent me yesterday. In fact, Karsten recently purchased an item that incorporates both crypto (a cipher disk) and currency (a coin). This “crypto currency” device is by no doubt a lot older than BitCoin, so calling it the world’s oldest crypto currency is not exaggerated.


The cipher wheel medal

Here’s the front-side of Karsten’s acquisition:


Precisely speaking, this item is, of course, not a coin, but a medal (i.e., it was not meant for payment). The medal shows St. George, a popular Catholic saint, riding his horse and fighting a dragon. This motive has been extremely popular in Christian art history. The following painting by Paolo Uccello (1397-1475) is one out of many I found when searching Google images:


The medal inscription “S: GEORGIUS EQUITUM PATRONUS” is Latin. It means “St. George, patron saint of horse riders”. It seems likely that this medal was worn by horse riders.

Here’s the rear-side of the item:


As can be seen, this is a cipher disk. The central ring of the device can be turned, so the cipher disk is operational.

It should be clear that an encryption made with such a device is not very secure (unless one turns the wheel several times during the encryption process). However, in my view, this item doesn’t look like a toy. Incorporating a cipher disk into a medal might have been a way to hide it.


Does a reader know more about it?

To my regret, almost nothing is known about this device. As Karsten found out, a picture of such a medal is available on Wikimedia:

Photograph by Rama, Wikimedia Commons, Cc-by-sa-2.0-fr

According to the Wikimedia page, this specimen of the St. George medal is a part of the cryptography collection of the Swiss Army headquarters (does a reader know where this collection is located and if it is accessible to the public?).

The origin of the device is probably France. The inscription “Breveté S.G.D.G.” (“Breveté Sans Garantie Du Gouvernement”) is French and translates to “Patent without government guarantee”. Statements of this kind were used in France until 1968.

Can a reader find out more about this crypto medal? Karsten and I would be very interested.

Further reading: A beautiful Spanish Encryption device


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Kommentare (7)

  1. #1 Rossignol
    Paris, France
    29. Juli 2018

    This device is the “chiffreur universel de Flamm” (Flamm’s universal encryptor) circa 1896.

  2. #2 Thomas
    29. Juli 2018

    Since Saint George Thalers were widely used as amulets by soldiers, the combination with Flamm’s chiffreur obviously served as a simple encrypting/decrypting device for soldiers in the field.

  3. #3 Rossignol
    Paris, France
    29. Juli 2018

    Here is an English translation of the article (Google translate):

    The universal encryptor. – The little device we depict here (fig.83) makes it
    possible to establish a correspondence without any other than those who have the
    key can understand this correspondence.

    The universal cipherer, so named by its inventor, Mr. Flamm, serves to secret
    communications and can be useful to the military or trade. This device consists
    of two parts: one fixed, the other mobile.

    The outer or fixed part contains a series of digits and a dash (-) and a
    question mark (?). (The dash is used to form the fractions.) Immediately below
    are placed the letters of the alphabet in their natural order, with the
    exception of the letter y, a series of numbers, all of two digits, and below
    which are also the letters of the alphabet, but not in their natural order. This
    part serves to indicate the letters or numbers on the outside.

    Example: two people chose the key B/Z; B is on the part fixed outer and Z is
    on the movable inner part. To have the key, one only has to turn the moving part
    until the letter Z comes to place below the letter B. We would do the same for
    any other key chosen (key of letters or numbers). Thus, with the key B/Z the
    letters Z, I, D, R, etc., of the inner circle will correspond to the letters B,
    C, D, E etc., etc., of the outer circle, and then write for the letters to
    encipher the circle outside, the corresponding letters of the inner circle.

    a. Example : Key B/Z Je pars demain
    Br ampf drnpwe

    The letter or dispatch may consist alternately of letters and letters numbers,
    since we can substitute for each letter the corresponding number.

    b. Example : Key A/M suis arrivé
    o21p15 m25b11e18

    By this means we avoid the successive repetition of the same two letters in a
    word. If we choose numbers as key, we proceed as in case a, the first number
    appearing in the fixed part (outermost circle) and the second on the moving part
    (inner circle or encrypting circle).

    c. Example : Key 10/32
    Venez 11 1/2 matin
    33 25 23 25 17 14 24 27 12 31 24 29 26 23

    The person who would receive this telegram would necessarily be brought to
    translate 11 1/2 by the letters, but as it would form a word having no meaning,
    then, in a similar case, it will have to use the figures of the outer circle. If
    one feared, using only one key, that the first word was understood by a third
    party and that with the help of this first word, he could guess all the rest of
    the dispatch, we can establish a more difficult combination again and stipulate,
    for example, that we will have a special key for each word. Of so, every word
    would have its own key.

    From the foregoing, it can be seen that combinations relating to the key and its
    modifications may vary to infinity, and it is impossible for anyone is not
    initiated into the secret of deciphering the correspondence.


    It’s very strange that the letter Y is not in the alphabets of this disc.
    Generally, in French, the W is deleted (as in the Bazeries’ cylindrical cryptograph
    ) or postponed in the end as in the Kronberg’s cryptograph (the so-
    called “Mexican army disc”).

  4. #4 Karsten Hansky
    29. Juli 2018

    thanks for information and translation. I do not speak French so it was difficult for me to find out more.

    Nice to hear that it was around 1900. I do not think that the device was very successful because it is very simple.


  5. #5 Klaus Schmeh
    30. Juli 2018

    @Rossignol: Thanks for this information.

  6. #7 Karsten Hansky
    31. Juli 2018

    This seems to be an image of the 1875 device which is described in the book: