Henry Debosnys (1836-1883), a convicted murderer, left behind four cryptograms, which  are unsolved to date. Breaking them could shed light on the many mysteries that surround this case.

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It’s about time to finish my series about the 50 most famous unsolved cryptograms. Number 3 on this list is the case of Henry Debosnys (1836-1883) from Essex Couty, NY, who left behind four encrypted messages. These cryptograms represent one of the most intriguing mysteries in crypto history. As only few crypto experts have occupied themselves with these messages so far, chances to solve them are not too bad.



Elizabethtown Post


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Henry Debosnys

Henry Debosnys was alledgedly born in Lisbon, Portugal, in 1836. Of French origin, he emigrated to the United States as a young man. In 1882 he settled in Essex County, where he immediately started courting a widow named Elizabeth Wells. After only a few weeks, the two married. A few months later, Elizabeth Debosnys was found murdered.


Source: Schmeh

Henry Debosnys became the main suspect in this murder case and was arrested. After the local law court had found him guilty, he was hanged on April 28, 1883. Today, Debosnys’ skull is on display at the Adirondack History Center Museum in Elizabethtown, NY.


Source: Schmeh

Henry Debosnys was a highly intelligent man. He was well educated and spoke several languages. He wrote poems and drew pictures. However, Debosnys was also described as a manipulative, lazy egoist, and even as an outright psychopath.


A forgotten case

The Debosnys case was almost forgotten for more than a century. The story was neither mentioned in the crypto history literature nor in true crime books until a decade ago. Then it was brought back to public attention by local author Cheri Farnsworth, who described the case in her 2010 book The Adirondack Enigma. Most information provided in this article stems from this book.


Source: book cover

The Debosnys case is decribed in my book Codemacher gegen Codeknacker. Craig Bauer covered it in his book Unsolved!.


Was Henry Debosnys guilty?

There’s much evidence supporting that Henry Debosnys was indeed the murderer of his wife Elizabeth. Anyway, Debosnys asserted his innocence. On the other hand, Elizabeth Wells already was Debosnys’ third wife, with both of his earlier spouses having died young and in strange circumstances. It is therefore well possible that Debosnys even was a triple wife-murderer.

On court, Debosnys claimed that “Henry Debosnys” was not his real name and that he lived on a false identity. It is not clear whether this statement was true.


Cryptogram #1

While in prison, Henry Debosnys created a number of texts and pictures. Four passages of the writings he left behind were encrypted. All four of these cryptograms are still unsolved to date. It is far from sure that these encrypted messages contain anything useful, but there is at least the chance that the plaintexts shed some light on the open questions of this case.

Cryptogram #1 is a six line text written in an alphabet consisting of simple symbols.




Cryptogram #2

Here’s the second cryptogram:





Cryptogram #3

Cryptogram #3 is the shortest of the four:



As blog reader Thomas Ernst pointed out, the cleartext part of this page (written in French) contains may spelling errors. French was probably not Debosnys’ mother language.


Cryptogram #4

The fourth cryptogram resembles an encrypted poem:




Some of my readers have posted interesting facts about this poem-like text (in German). Check here for details.

I have blogged about the Debosnys cryptograms several times before. People have asked me if there is a transcryption, but I’m not aware of one. The alphabet Debosnys used is large, which makes transcribing the text quite complicated.

Considering the large alphabet, it seems unlikely that the cipher used is a simple substitution (MASC). Perhaps, Debosnys applied a homophonic cipher or a code. Of course, it is also possible that all these cryptograms are a mere hoax. Perhaps a reader can help to solve this mystery.

Further reading: An extraordinary encrypted book: George Orwell’s “1984” enciphered in color

Kommentare (2)

  1. #1 Klaus Schmeh
    8. Januar 2020

    Karin Isberg via Facebook:
    Love the Lego demo too.

  2. #2 Marthy
    17. Februar 2021

    I think, Henry should have been a member of some freemanson, Scottish ritus.In the ciphers, there are used freemanson symbols, Compasses, angle, hammer,trowel. Cryptogram #2 at the end. There are 2 hands (man, woman)and L.M.S. Inch finger is in the special position used by members of freemanson.