The Post Quiz: Decipher This
Created | Updated May 8, 2016
Are you ready to become a cryptographer?
The Post Quiz: Decipher This
Did you know that the guy who ran the cryptography lab for the US during World War I started out by trying to prove that Francis Bacon wrote the works of Shakespeare?
Neither did we, but it's a weird enough reason for all you spies-in-training to try out this puzzle. It's an actual letter by 'Colonel' George Fabyan, aforesaid nutcase, to a [real] General Churchill back in 1913. Problem is, a vital sentence is coded. See if you can decipher it.
If you succeed, there's a time machine waiting to take you to Bletchley.
CHICAGO
Sept. 6, 1913
Dear General Churchill:
I carefully note letter of September 2nd, over your signature. SGDQDHRMNLNQDFTDRRHMFHMBQXOSNFQXOGXSGXMSGDQDHRHMXKFDAQX. "Guessing" is undignified – "assumption", sounds lots better.
I don't question the sincerity of any of the General Officers but some of the subordinates have made us dance without giving us a chance to select the tune, but I suppose we will forget it some day.
If Riverbank had invented a cipher and 1 had put myself on record tliat it was indecipherable and had been awarded the D.S.M. and had the cipher printer especially mentioned in the citation and my boss had been made the Knight of St. George and St, Michael on account of the machine printing across the ocean , I doubt if I would be very enthusiastic about anybody proving that "my doll was stuffed with sawdust1" and I think I very likely would put as many obstacles in their way, I enclose copy of a message sent us by Lauborgne sometime ago which we never tried to work on because it was not long enough and yet, when he was here, he said we had no right to jump at any conclusions as to the number of cycles or the length of the message. He knew, at the time, we wanted three complete revolutions of the tape and left us to infer that this message covered that and confirmed it when he was here.
I wish, if possible, someone in the M.I.D. could ascertain in regard to this and see if the message is not less than one cycle and for that reason, impossible to decipher.
I don't understand Why Lauborgne don't send us the messages. The machine has been set up for over three weeks and yet, he cannot send us two hours work but asks for one delay after another, Which Riverbank construes as trying to get another scheme to work out.
Sincerely yours,
[unreadable signature]
To: General M. Churchill,
Woodward Apartment,
2301 Connecticut Ave.,
Washington, P. C.
Declassified and approved for release bv NSA on 08-05-2014 pursuant to E.O. 1352.
(Notice we're carefully not breaking any laws.) For the answer, click the picture.
NOTE: The cipher is not really in the original letter. It was added by us, and we're duffers at this. George Fabyan was a real expert at cryptanalysis (his researchers laid the foundations for the NSA) who would never have stooped to such a wussy cipher.
