SOMERTON MAN: OLD CODES, NEW CODES & CONCEALMENT 2, THE POEM CODE

THE POEM CODE

This is the second in our series of WW1 and WW2 codes that were in use by British intelligence services, in fact this particular one was used with great effect by Leo Marks of SOE. An example of his work follows the first few paragraphs.

THE POEM CODE EXPLAINED

This is how a poem code works. Start with a poem which you have memorized: it needn’t be especially long, nor complete. For example, this fragment from Ulysses will do: “for my purpose holds to sail beyond the sunset, and the baths of all the western stars until I die.” Select five words as a key from this: say, “for”, “sail”, “all”, “stars”, “die.” String them together and then number the letters, starting with “a” as 1, the second “a” as 2, etc.; or if there is no second “a”, then “b” is numbered 2; if no “b” then “c” gets labelled 2, and so on until we have numbered all letters. The result:

Now suppose we want to encrypt the message, “We have run out of cigars, situation desperate.” Incidentally, encoding must not be confused with encrypting—our message, for example, may be encoded, “Nothing left for Mark Twain to do, dammit” (where we hope the person hearing this is clever enough to figure it out). Since there are 18 letters in our poem selection, we write out the message in groups of 18 letters, padding the end with nonsense letters, like this:

Note the first letter from our poem snippet, an “f”; under it is a 6: the second letter is an “o” and under it is a 12. In our (padded, grouped message) the 6th column of letters is “eud”, and under the 12th is “tdk”. It was more or less standard practice to send the encrypted message in groups of five letters, which reduced (but of course did not eliminate) transmission errors. So the first part of our message would be:  eudtd koekc pmwrt.

SOE Poem Code

The 'Slideshare' presentation below is courtesy of Derek Buff, it discusses a Leo Marks Poem, in fact it is the one he gave to an SOE operative, Violet Szabo, you may recall her name, a film was made of her work and her sad passing, CARVE HER NAME WITH PRIDE. It is an excellent presentation and one I hope you will enjoy.

Poem Codes from Derek Bruff

We have a number of upcoming posts in this same vein and all related to various war time codes including the Cold War and agents such as the Somerton Man, Pavel Ivanovich Fedosimov..