Peter Rabbit” is a new 3D animated comedy film based on a story by Beatrix Potter (1866-1943). Potter is known to crypto history enthusiasts because she left behind an encrypted diary.

If you happen to live in the USA or the United Kingdom, you might have already watched Peter Rabbit, a new animated comedy film. Here in Germany, we still have to wait for a few weeks before this movie is released. For those of you who haven’t seen it, here’s the official trailer (there’s also a German version; the German film title is Peter Hase):


Beatrix Potter

Why do I tell you about this? No, it’s not that the plot of Peter Rabbit is about cryptography (unlike Enigma, The Immitation Game, Windtalkers and a few other movies). It’s because the character Peter Rabbit was created by a woman who is mentioned in my book Codeknacker gegen Codemacher and in other crypto literature sources: Beatrix Potter.


Beatrix Potter (1866-1943) was an English writer and illustrator best known for her children’s books. Her most successful work is The Tale of Peter Rabbit.


The plot of this book is about a family of anthropomorphic rabbits. The mother rabbit cautions her young against entering the vegetable garden of a man named Mr. McGregor. While her three daughters observe this prohibition, her son Peter enters the garden to snack on some vegetables. He is spotted by Mr. McGregor and gets in trouble.


The Tale of Peter Rabbit is today a children’s book classic in the Anglo-Saxon world. In Germany, neither Beatrix Potter nor her book are especially popular. I had never heard of Potter before I became interested in crypto history, not even in my English classes at school.

The movie Peter Rabbit tells a similar story as the book, but it is set in today’s world. Among the human characters in the film is a woman named Bea – a reminiscence on Beatrix Potter.


Potter’s encrypted diary

At about the age of 14, Beatrix Potter began to keep a diary. She wrote it in an encryption code (a MASC) of her own devising. Her journal was important to the development of her creativity, serving as both sketchbook and literary experiment. In tiny handwriting she reported on society, recorded her impressions of art, recounted stories and observed life around her.

The diary was decoded and transcribed by Leslie Linder in 1958. Here’s a detailed article by Cara Giaimo about Linder’s deciphering work. As Potter’s encryption method was a pure MASC, it was not very hard to break.

However, Giaimo’s article doesn’t contain a scan of the encrypted writing. When I wrote my book Codeknacker gegen Codemacher, I tried to find pictures of Potter’s diary via Google, but to no avail. So, I contacted the The Beatrix Potter Society. I received a reply telling me that there’s a book titled The Journal of Beatrix Potter 1881-1897 by Frederick Warne (there are several editions; according to the Beatrix Potter Society, the one from 1987 is the best).

To my regret, this book doesn’t bother much with Potter’s encryption method, but at least, it contains the following scan of a diary page:


This scan has been available on my encrypted book list (Potter’s diary is number 00020 on it). It appears to be difficult to find other pictures of Potter’s diary online. This scan was linked by Bruce Schneier, when he wrote a short note on his blog about the Cara Giaimo article (it doesn’t happen very often that Bruce writes about crypto history, by the way).

Here’s another blog post that uses the scan. I’m a little confused about another picture in this article. It shows the following two book pages:


As can be seen, this text is mainly written in the clear, but it contains a few encrypted passages. Was it written by Beatrix Potter, too? If not, who wrote it? Can a reader decipher the encrypted words?

Further reading: The Zodiac Killer code is solved – at least in this new movie


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Kommentare (4)

  1. #1 Thomas
    1. März 2018

    The last image shows two pages of the “Heelis family cookbook” held by the family of Beatrix Potter’s husband, According to the object description it wasn’t written by Beatrix Potter.
    The ‘encrypted’ words seem to be Greek cleartext, f.e. the word “scandalon” is legible on the right page.

  2. #2 Thomas
    1. März 2018

    These two pages don’t contain partlyvenciphered text but etymological musings on the resemblance of certain English and Greek words.

  3. #3 Thomas
    1. März 2018

    The cipher she used in her diary is shown here:

  4. #4 Klaus Schmeh
    8. März 2018

    >The last image shows two pages of the
    >“Heelis family cookbook”
    Thanks (and thank you for the many other comments you have posted). This crypto mystery (which is actually not really cryptographic) appears to be solved.