Two encrypted newspaper advertisements from 1875 are still unsoved. Is the first one the key to the second?
The book The Agony Column Codes & Ciphers by Jean Palmer (i.e., Tony Gaffney) …
… presents over a thousand encrypted newspaper advertisements from Victorian England. While Tony has solved many of these cryptograms himself (the solutions are given in the book), some still wait to be deciphered. On Klausis Krypto Kolumne I have written about some of these.
Many of these encrypted newspaper ads contain love messages. Others were placed by business people in order to provide information to partners and customers. Ignatius Pollaky, …
… a private investigator of the Victorian era, communicated via newspaper advertisements, too.
Two advertisements from 1875
One of the most puzzling encrypted newspaper ad series described in Tony’s book was published in the Evening Standard in 1875.
This series consists of two advertisements. The first one is contained in the May 8, 1875 issue:
W. Str 53. Catokwacopa. Olcabrokorlested. Coomemega. Sesipyyocashostikr. Rep. – Itedconlec mistrl. – Hfsclam 54, 3 caselcluchozamot. 1. 6. 9. Mopredisco. Contoladsemot. Iadfilisat. Qft. Cagap. Balmnopsemsov. Ap. 139. – Hodsam 55, 6. Iopotonrogfimsecharsenr. Tolshr. Itedjolec. mistrl. – Ding Declon. Ereflodbr.
Twelve days later, on May 20, a second ad in the same style was published:
W. – Umem 18. Poayatlgerty. Dpeatcnrftin. Nvtinrdn. Dmlurpinrtrcamur. Etd. – Atndngtnsurs. Otenpu. – Eftdorshpxn. 18. Ndtsfindseseo. Cotegr Tavlysdinlge. Ngtndusdcndo. Edrstneirs. Ui, Ndted. iolapstedtioc. A. P. 138. – Yxn. 18. 18. Wtubrfftrstendinhofsvmnr. Dily. – Atdwtsurs. Oatvpu. – Y Arati. Rileohmae. – This will be intelligible if read in connection with my communication published in this column on the 8th inst.
Note that the last sentence of the second ad is in the clear. If it is correct, the first ad might be the key that is necessary to decrypt the second one (or the other way round).
I published a first blog post (in German) about these ciphertexts (I call them Catokwacopa cryptograms because of the first word in the first ad) in 2015. There were a couple of comments, but nobody came up with a solution. Earlier this year, I wrote a second post about the Catokwacopa cryptograms.
A transposition cipher?
The Catokwacopa cryptograms look different from most other encrypted advertisements in Tony’s book. Words like “Catokwacopa” and “Olcabrokorlested” are pronounceable, which is unusual for most encryption methods. My first impression was that the number of vowels is higher than usual in a ciphertext, which is evidence for a transposition cipher (encrypting a text with a substitution cipher usually lowers the number of vowels). To check whether my suspicion was correct, I performed a frequency analysis with CrypTool 2. Here’s the result:
This frequency distribution is consistent with an ordinary English text. This makes it very likely that we deal with a transposition cipher here.
The question is now what kind of transposition the author of these ads used. My guess is that the two ads need to be mixed somehow (e.g., letter 1 from ad 1, letter 1 from ad 2, letter 2 from ad 1, letter 2 from ad 2, …). After my last blog post about the Catokwacopa cryptograms, several readers (Thomas, Lance Estes, Dave, and JA) looked at this hypothesis in more detail. It appears to make sense, but so far, no solution has been found.
Thomas remarked that the letter Q, which appears several times in the first ad, might be helpful, as it is almost always followed by a U. The first ad contains a Q. Is this of any help?