By Sam MacKenzie (2014 Cohort)

Dorabella LetterIn 1897, composer Edward Elgar sent an enciphered letter to his friend Miss Dora Penny, nicknamed Dorabella. The Dorabella Cipher may tell a tale of a secret affair between two unlikely lovers. It may be a casual letter to a friend who was important in the sender’s life. It may be gibberish. Regardless of what was said in the Dorabella Cipher, the contents have remained a mystery for over a century despite the interest shown by a countless number of cryptanalysts.

Edward Elgar was a famous composer, renowned for the famous graduation song Pomp and Circumstance March No. 1, who dabbled in other hobbies as well, including cryptography. Elgar was already m arried to a younger woman named Caroline who was once his student, but he undoubtedly enjoyed the company of Miss Dora. So much so, that in his famous work The Enigma Variations (a series of short musical portraits), he dedicated a section to her named Dorabella that featured woodwinds to represent her laughter (Peterson, 2009).

Long before Edward was known as a world famous composer, he wrote a mysterious letter, which continues to baffle the world to this day. On July 14, 1887, the letter appeared on Miss Penny’s doorstep. Miss Penny published the enciphered letter in her memoirs of Elgar to ask for possible solutions because she never had the slightest idea what it meant (Sams, 1970).

Clearly this cipher does not carry the same importance as the Enigma Machine (which was utilized by the Nazis to generate their encryptions), nor does it offer the same reward as decoding the Beale Ciphers (where the decoder would have been rewarded with a hefty amount of gold). Despite the lack of material significance, the Dorabella Cipher is still a popular mystery.

Dorabella MessageWhat does it mean?

Attempts to solve the Dorabella Cipher have been met with varying levels of success. The cipher features three rows and 24 different symbols of squiggles, totaling 80 characters. Most of the characters resemble the letter E, which could have something to do with Edward Elgar’s initials, EE. In 1887, computers were not yet spitting out complicated encoding systems, and it is unlikely that Edward could have expected Miss Penny to decipher anything too complicated. Therefore, most historians agree that it was enciphered using a substitution method (Kile, 2012).

In this case, a substitution encoding method would mean that each squiggly symbol represents a different letter of the alphabet. Although there are 26 letters in the alphabet and 24 different characters in the cipher, Edward could have easily worked around using infrequent letters such as “Z”, “X”, and others. Cryptanalysts commonly use frequency analysis, which matches the most common squiggles in the cipher to the most common letters (A, E, T), as a method to decode substitution ciphers. This frequency analysis has shown that a substitution cipher is plausible for the Dorabella Cipher (Kile, 2012). This finding supports the hypothesis that Elgar probably could not have employed a more complicated enciphering method. Despite the usage of frequency analysis, the cipher still remains unsolved.

Some challenges that cryptanalysts have encountered while attempting to solve the Dorabella cipher include the lack of cipher text and the private language that seems to have existed between Miss Penny and Edward Elgar. Frequency analysis is helpful for solving substitution ciphers, but is much less effective when there is so little cipher text to analyze. With less cipher text, the difference in frequency between the popular and unpopular symbols is too small to provide meaningful information about the symbols.

Additionally, Tony Gaffney, a renowned cryptanalyst, believes that their mixture of inside jokes and slang makes decoding the Dorabella cipher exceedingly difficult (Pelling, 2012). Decoding this letter would be similar to trying to decipher a letter written in an unknown language. Cryptanalysts are not only required to decipher the letter into plain English, they must also make random guesses at the inside jokes the letter could contain.

The mystery of the Dorabella cipher is not who sent the enciphered letter, or why, or how. Instead, the mystery is what was said in the letter. Most historians agree there were no sexual relations between Miss Penny and Edgar, since he was happily married, but they were very close and remained life long friends. When Edward was later questioned about the contents of the cipher by Miss Penny he reportedly said, “I thought you, of all people, would have guessed it” (Peterson, 2009). Perhaps the contents of the enciphered letter would allow us to better understand the mysterious relationship existing between Edward and Dora.

It is unlikely that the cipher carries relevant mathematical aspects, as neither Miss Penny nor Edward Elgar were mathematicians who were skilled with ciphers. Therefore, this cipher carries more historical significance. Many musicians would love to see into the mind of the famous composer, but that is beginning to seem more and more unlikely.

Will the cipher ever be solved? Generally, ciphers that are decoded the quickest are the ones that are the most urgent or have the highest reward. In either of these cases, the cipher receives a large amount of effort and resources. On the other hand, the Dorabella Cipher has no reward and no urgency, but rather is considered a hobby for idealists who enjoy a good story. As a result, it is doubtful that this cipher will be decoded considering the resources already unsuccessfully applied to trying to decode it.. It seems the mystery will remain unsolved, an inside joke for Elgar alone.

This post is part of a series of essays on the history of cryptography produced by students at Vanderbilt University in honor of the release of The Imitation Game, a major motion picture about the life of British codebreaker and mathematician Alan Turing. The students wrote these essays for an assignment in a first-year writing seminar taught by mathematics instructor Derek Bruff. For more information on the cryptography seminar, see the course blog. And for more information on The Imitation Game, which opens in the US on November 28, 2014, see the film’s website.


Peterson, E. (2009, May 1). Unsolved Mysteries: The Dorabella Cipher [Web log]. Retrieved from:

Kile, J. (2012, June 14). The Dorabella Cipher and a Possible Method for Deciphering [Web log]. Retrieved from:

Pelling, N. (2012). Dorabella Cipher [Web log]. Retrieved from:

Sams, E. (1970). Elgar’s Cipher Letter to Dorabella. The Musical Times, Vol. 111. Retrieved from:

Image Sources:

Dorabella Cipher Image (photograph). (2011). Retrieved: October 30, 2014. From:

Cynicalview (photographer). (2011). Envelope (photograph). Retrieved: November 11, 2014. From: