Dorabella Cipher. Cryptography peppers the world s history as an aid to military communication

Transcription

1 Courtney Hulse November 1, 2010 Dorabella Cipher Cryptography peppers the world s history as an aid to military communication and national strategizing. During the Second World War, cryptography was perhaps the key factor that allowed the Allies to come home victorious, and before that, kings, like Louis XIV of France, used cryptography to maintain security of their political plans, but cryptography has not always had such a serious use. Cryptography has been used as a means of correspondence between forbidden lovers, and also as a series of challenges among friends as can be seen on the web in the form of sites dedicated to unsolved ciphers. The Dorabella cipher was one example as such: a code simply for fun without any weighty significance. Sir Edward William Elgar, the virtuosic composer of Pomp and Circumstance March, sent an enciphered note to his close friend, Miss Dora Penny, in Elgar had been visiting with Dora s family, and many believe he was romantically linked to Dora, despite her being many years his junior (although other sources say he visited with his wife, Alice). The note was included in a letter thanking Dora s family, and although it was clearly addressed to her ( Miss Penny was written on the reverseside), the fact that her whole family would see the note suggests that the message was not a private affair. Probably, Elgar wanted to offer a challenge to his friend, or he was referencing something they had discussed during

2 his visit. Dora knew Elgar well enough to understand his peculiar writings, which included phonetic spellings, puns, and cryptograms (i.e. xqqq signifies excuses, IXpin signifies ninepin ). Occasionally in his notes to her, Elgar would change the order of the letters of a word just to keep the reader on her toes. For example, cipher might be written as crehpi. (Palmer) Because of this arbitrary style of writing, Elgar s cipher text has countless possible solutions because the plaintext is not required to spell out actual words. Dora herself never deciphered the note; she died without ever discovering its meaning. However, she did publish the cipher text in her memoirs, and it has become a popular unsolved cipher, known as the Dorabella Cipher for the nickname Elgar gave her. There are many cryptanalysts who claim to have deciphered the Dorabella, but it is impossible to tell who, if anyone, is correct, as there are countless probable messages, and Elgar never revealed his intended meaning. The cipher consists of a series of cusps, oriented in different directions, containing one, two, or three cusps, and many believe the symbols are derived from the way Elgar signed his initials in cursive. It is also possible, however, that the cusps represent the letter c as in C major, the most basic scale on the piano. Perhaps Elgar is hinting that the note, if it is actually a melody, should be played in C major. (Effluvium) Another musical possibility could read the cusps as representations of one-note, two-note, or three-note chords. (Ancient) The note contains only eighty-seven characters, a limited cipher text, which makes it very difficult to break. Longer cipher texts are easier to decrypt because there is a greater likelihood for repetition of words and phrases, which can be used as cribs.

3 Frequency analysis was a tool developed by Al-Kindi as early as the tenth century, which analyzes a cipher text in terms of the number of occurrences of each individual letter. More letters allow for a more accurate frequency analysis, an accurate analysis can almost completely decrypt monoalphabetic ciphers. (Singh 17) Despite the brevity of the cipher, cryptanalysts have tried frequency analysis, but the result is always gibberish, indicating that it must not be a monoalphabetic substitution cipher. Even later, when additional cipher text was found scribbled in the margins of a concert program, the frequency analysis still yielded no helpful result. (BBC) The failure of this initial test led many to believe that the Dorabella cipher was doubly encrypted. Popular opinion has since departed from this belief, instead considering Elgar s tendencies toward artistic thinking. However, this trend is a dangerous one, because with enough creativity, almost any solution that looks wrong can be justified by tweaking the spelling and adding cryptograms as Elgar might have done. One theory hypothesizes that there was a connection between the cipher and Elgar s music. One of his grand works, Enigma Variations, which served as the namesake for the German Enigma machine that would come later, used many of his friends as inspiration for the music, coding the notes in Morse code, and personalizing the melodies to sound like his friends. For example, Dorabella had a stutter, so her section of the Enigma had quickly repeated notes that emulated the sound. (New Scientist) The ensuing idea is that the Dorabella cipher was similarly related to a piece of music. Eric Sams, a twentieth century musicologist, proposed that perhaps the eight different positions of the cusps represent rotations around a clock-like diagram where each stop is a progressing musical note (do, re, mi, fa, so, la, ti, do), and where the three variations of

4 cusps represent sharps, flats, and natural notes, making the cipher text a melody instead of a message. (Unsolved) The groupings of eight symbols of similar cusp-shape seem to indicate that the cipher, if it is a melody, would span three octaves. (Ancient) There may be something to the clock analysis, as there were drawings of similar dials found in a late notebook of Elgar s; perhaps he was trying to remember the encryption that he had used. (Ancient) Many have tried to capitalize on this clue, and they have come up with a number of varying answers. One cryptanalyst uses a compasslike wheel with three dashes on the edge of each quadrant, and on each section of the dissecting axes crossing through the circle. The resulting twenty-four dashes supposedly represent an alphabetical substitution, and the symbols line up so that the open part of the cusp faces toward the origin of the compass. (Palmer) Note, that there are only twentyfour symbols, yet there are twenty-six letters in the English alphabet. Kevin Jones, a professor at Kingston University in London, speculates that two of the more uncommonly used letters, probably J and V, share a symbol with their neighbors. (BBC) It is also possible that the cipher uses the Biblical Greek alphabet, which does contain twenty-four letters, but this is unlikely. (Ancient) A confident cryptanalyst writes, the cipher has now been solved it turns out to be a simple substitution cipher. (Roberts) He postulates that Elgar used the keyword phrase: Lady Penny, writing in code is such busy work, which becomes LADPENNY WRITIGC OSUHBYWK when repeated letters are removed, beginning at the end. This

5 phrase is then divided into three sets of eight letters, supposedly corresponding with the eight different orientations of symbols with one, two, or three cusps. Roberts claims the plaintext reads, P.S. Now droop beige weeds set in it pure idiocy one entire bed! Luigi Ccibunud luv ngly tuned liuto studo two. (Roberts) After some editing, the ensuing message could discuss gardening and Luigi Cherubini, the Italian composer, or it could easily be nonsense. Another cryptanalyst, Jean Palmer, found the plaintext, B LCAT IE AWR USIN NF NN ESHLL WY YOUD INTAQRAYEIN NET DMINUNEHO M SRRY YOU THEO O THS GOD THEN M SO LA OD E ADYA, and deciphered it as, Bella hellcat i.e. war using hens shells is why your antiquarian net diminishes hem sorry you theo oh tis God then me so la do E Adieu. This translation is also quite a stretch, even when Palmer points out a reference in a letter of Dora throwing eggs at Elgar. (Palmer) It is clear that the cryptanalysts took liberties with spelling and interpretation to fit their work. However, this approach is not so ludicrous; in fact, it is almost necessary given Elgar s bizarre use of language. Many of Elgar s legitimate writings resembled nonsense, so it is hard to tell what partial decryptions should be pursued further. The attempts as outlined above have merit, but they are wasted because there is no answer key for comparison. In 2007, the Elgar Society, in the United Kingdom, created a contest to celebrate the 150 th anniversary of Elgar s birth. They offered a prize of 1500 pounds to the person who could produce the most logical solution to the cipher. The society received many submissions in addition to the ones outlined above, some written in Latin, others written backwards, and still others using words that were not used colloquial until after the time the code was written. (New Scientist) None of the submissions were satisfactory, and

6 consequently, no prize was awarded. To be fair though, there is no way for the Society to know if the true plaintext can ever be derived because Elgar seems to have taken it to the grave. There even exists the possibility that the Dorabella cipher was simply a silly note meant to fool a friend and there never was any real meaning to his scribbles. Perhaps the whole ordeal was meant to be a joke; likely the world will never know. Regardless, it has become a source of fascination for the cryptographic community. The Dorabella Cipher was surely one of the least constructive examples of cryptography, but it found a beneficial use in its later life. The cipher was used as a test for those recruited to Bletchley Park, the famous British center for cryptanalysis. Churchill had ordered the leaders at Bletchley to assemble a diverse group of minds. (Singh 179) To do so, they gave the recruits known ciphers and watched how they went about decrypting them; the Dorabella cipher was one of these tests. It did not matter that the cipher was a dead end, because the object was to look at technique. (Effluvium)

7 Works Cited The Dorabella Cipher. Posted by nickpelling February 25, Accessed October 27, Hoschel Jr., George, Tony Gaffney, Tim Roberts, Jean Palmer. Unsolved Problems: In Number Theory, Logic, and Cryptography. Accesed October 27, unsolvedproblems.org/s04.doc Jones, Kevin. The Dorabella Code. Last updated August Accessed October 27, Jones, Kevin. Breaking Elgar s Enigmatic Code. New Scientist Magazine, issue 2470, pg 56. Published December 25, Accessed online on October 27, l Edward Elgar s Dorabella Cipher. Ancient Cryptography. Last post: March 15, Accessed October 27, Website of The Elgar Society and Elgar Foundation. Last updated October 1, Accessed October 27, BFG. The Dorabella Cipher: Analysis 1. Effluvium of Consciousness: Brainfarts From the West Coast. February 27, Accessed October 27, Sams, Eric. Variations on an Original Theme (Enigma). The Musical Times, Mar. 1970, pg Accessed October 31, Singh, Simon. The Code Book. Random House: Palmer, Jean. The Agony Column Codes & Ciphers uncracked-codes/ Note: Professor Kevin Jones was the chair of the judging panel for the Elgar Society s competition.