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Clues (or red herrings) to the Dorabella Cipher

dorabella

Background

In 1897, the English composer Edward Elgar sent a letter containing an encrypted message (seen above) to his aquaintance, Miss Dora Penny (nicknamed Dorabella). To this day, the meaning remains unknown.

Analysis

The New Scientist article suggests that the 26 letters of the roman alphabet are probably mapped to the 24 symbols by using the same symbol for I=J and U=V. Assuming the (arbitrary) key

    S     W     Z
      R   U   Y
        Q T X
    P O N   A B C
        K G D
      L   H   E
    M     I     F

the ciphertext can be read as

   BPECAHTCKYFRQDRIRRHPPRDXYXGFS
   TRTHTCKLCERREHGQTRFRHUSQDXKKXFS
   ESHUSEDUWGSERHUQSDCPGSHCDXC

i.e. the first symbol is two semi-circles with their open sides facing east, we pick the second eastern letter, B, etc.

dorabella
Image made by Robert S.

The BBC article mentions an exercise book where Edward used the same symbols again in 1920:

notebook
1920 exercise book, birthplace museum

In the same article, Kevin Jones adds:

Elgar did indeed use this cipher elsewhere. As well as the examples in the 1920's exercise book, Elgar scribbled an 18 character code using the same cipher symbols in the column of printed programme notes for a concert he attended at Crystal Palace in April 1886 - opposite a musical example from Liszt's "Les Preludes".

liszt
1886 Liszt fragment, birthplace museum (click on image for full page)

From Edward Elgar: A Creative Life by Jerrold Northrop Moore:

On 10 April 1886 he went to the Crystal Palace to attend a performance in honour of the seventy-five-year-old Franz Liszt. Liszt was visiting England for the first time in many years, and Manns's orchestra surpassed itself. The old Abbe shook hands with Manns and bowed many times to a cheering audience. Edward recorded his own Judgement on this music with a cipher pencilled into his programme. It was an early instance of his interest in this arcane art, more secret than a pun yet with its own show of cleverness. Many years later the cipher on Liszt's music was decoded to read: 'GETS YOU TO JOY, AND HYSTERIOUS.' (footnote: communicated by Anthony Thorley, 1977) 'Hysterious' was a portmanteau invention: it married 'hysteria' with 'mysterious' throu a 'tear'.

Speculation

There are 24! (or 620,448,401,733,239,439,360,000, about 6.2*10^23) possible keys. It appears unlikely that Elgar expected Dora to deduce the key mathematically. I suspect the key was known to Dora, but she didn't recognize it as such.

Could the eight directions of the cipher symbols correspond to the eight directions on a compass rose?

Elgar and Dora shared a love for the Malvern Hills. According to Dora's memoirs, she received the letter on July 14th 1897, after a visit by Elgar and Alice earlier that month. She remembered one of the topics of conversation was map reading.

Could there be one specific map Elgar assumed Dora would think of? There is a unique map on top of Malvern Hills, in form of a toposcope at the peak of Worcestershire Beacon. More intriguingly, the toposcope was installed in the year 1897, in celebration of Queen Victoria's diamond jubilee. And it features drawings made by Troyte Griffith, a friend of Elgar's.

toposcope
Worcestershire Beacon, Malvern Hills, by Primed Minister

The only image of the toposcope found online doesn't have a high enough resolution to show details like names and other engravings. Other images show an outer ring around the plate with the map with further engravings, reading THE EARTH IS THE LORD'S AND THE FULNESS THEREOF, quoting psalm 24.

Maybe the engravings are placed in a way that allows to unambiguously associate three letters with each of the eight directions, so the monument is the translation key. The frequency distribution in the ciphertext matches that of the English language, but if Elgar used creative spelling and word choices (as he was known to do, in other letters) to defeat simple analysis, maybe the alogrithm IS just a simple substitution cipher, which hasn't been cracked yet due to the untypical properties of the enciphered text? However, would Elgar have thought that the letter would ever be analyzed by people with cryptographic skills?

Another explanation would be that while the substitution is monoalphabetic, there is some form of transposition. Something that Dora would have noticed visually, had she reversed the substitution, like writing lines from right to left, or rows (top to bottom, or reverse) instead of lines, or even diagonally. The ciphertext contains three lines, with 29, 31, and 27 symbols respectively. Should we assume the order is neccessarily line by line, from left to right? If so, why aren't there three lines of 29 symbols each? The spacing between the symbols does not appear to be precise. One possibly interesting property of the symbol set is that every symbol can be rotated and mirrored, always producing another valid symbol.

If you have any feedback, especially any detailed pictures of the toposcope, I'd love to hear from you. Please send (plain text, non-HTML) email to daniel@benzedrine.ch. -- Daniel Hartmeier, April 27th 2006

Update: more images of the toposcope were found: topodisk.gif, toposcopering.jpg, toposcope.jpg, toposcope2.jpg.

Quotes from Dora's book

Edward Elgar - Memories of a Variation
Mrs. Richard Powell
Third edition by Methuen & Co. Ltd. in 1949

Pages 6 and 7:

After luncheon he suggested a walk and we spent the afternoon
on the North Hill. How lovely it was up there! The wonderful
air and the view--I had never been to Malvern before. He
pointed out various places and landmarks and I said admiringly:
`You're as good as a map!'
`Better,' he said. `We'll do the Worcestershire Beacon next
time you come, only you must stay, not flit like this.'
He was as good as his word and on another occasion, we had
another lovely afternoon on the top of the world, `far away
from smoky towns', as he remarked. He soon found that I
was as keen on maps and map-reading as he was. Also he added
to the interest of these expeditions by bringing in all sorts of
stories about the various places that could be seen, and many
historical details, too.

Page 10:

I saw, for the first time, the poker-work design over the
study fire-place, of which I had heard. I thought it was beauti-
fully done and E. E. was very proud of his handiwork. It was
a phrase from the Walküre `fire music'. When they moved to
Malvern Wells they took it with them and placed it over the
study fire-place at Craeg Lea. I did not see it at Hereford.

Troyte Griffith: A Malvern Enigma in Malvern Theatres

Found through google (in April 2006), the original URL produces a HTTP 403 (Forbidden) error, but the following was readable through google's cache:

First published on Friday 17 October 2003:

Troyte Griffith: A Malvern Enigma n Malvern Theatres

The life and elusive character of Troyte Griffith, depicted as the seventh of Elgar's Enigma Variations, was elaborated on by Dr Jim Berrow, with Iain Young quoting the words of Troyte.

Born in 1864, Troyte came to work in Malvern as an architect, in offices above Abbey Gateway in the mid-1890s, which is when Elgar met him.

Troyte was a watercolour artist, as well as an architect and architectural historian. He designed All Saints' Church, The Wyche, along with a number of local houses and the toposcope on the Beacon.

Politics and music interested him too and he was secretary for Malvern Concert Club when Elgar founded it in 1903.

Troyte was a familiar figure as he rode his upright bicycle around Malvern. He never married and was rather solitary. His friendship with Elgar was based on complete trust and constancy.

In 1937, Troyte sent Carice all the letters Elgar had written to him. In many they shared jokes and the depth of their friendship was evident. Troyte died in 1942.

Dr Berrow's talk was the final event in a pleasurable and successful festival.

Jill Hopkins

Last updated on Tue Jun 9 20:28:27 2015 by daniel@benzedrine.ch.