Here’s a nice little thing that might possibly earn a Cipher Mysteries reader 100 US$!
Once upon a time in Copenhagen, a bright mathematics professor called Julius Petersen briefly stepped into the world of codes and ciphers. He wrote and published a pamphlet on cryptography called Système cryptographique, as well as a series of eight fortnightly articles on the subject for the weekly magazine NÆR OG FJERN (‘NEAR AND FAR AWAY’) – these ran from issue 150 (16 May 1875) to issue 164 (22 August 1875).
Though the articles did not actually say Petersen had written them, they are very much à la main de Petersen: and according to Professor Bjarne Toft, “we know from other sources that [Petersen] was the author (or one of the authors)“.
The point of interest for us is that the author(s) signed his / their name(s) in this unusual encrypted fashion:-
By 46, 9, 4-57, 3, 5.
This has left Bjarne Toft so mystified that he has offered money to anyone who can crack it:-
Does the dash ‘-‘ indicate that there are two authors? If so, the other could be Frederik Bing, who was an extremely good mathematician and a close friend of Petersen. Bing was mathematical director in the state life insurance company. And are the numbers dates? Or what??
I have offered a prize of 100 US$ to anyone who can give a convincing solution (convincing for me that means!).
Here are some things that might possibly help you crack such a tiny cryptogram (even smaller than the Dorabella Cipher!):
- Petersen’s full name was “Julius Peter Christian Petersen”, so his initials were presumably JPCP;
- Petersen’s friend’s full name was “Frederik Moritz Bing”, so his initials were FMB;
- The cryptogram looks an awful lot like a tiny book cipher (along the lines of the Beale Papers);
- If it is a book code, no obvious attempt has been made to use high numbers;
- If it is a book code, common letters would presumably tend to appear as smaller numbers, less common letters slightly larger numbers, with extremely rare letters potentially very large numbers: so the pattern here would seem to be “rare common common dash rare common common“;
- Surely the number one candidate book for testing the “book code” hypothesis would be Petersen’s Système cryptographique. Yet Worldcat lists no copies in the UK, so it would be down to someone to have a look at one of the scant few copies owned elsewhere…
Over to you, armchair cryptogram detectives…