Rules for the Playfair
To aid you in cracking the Playfair cryptograms
this month, I have included (as I did last month) a chapter from Helen
Fouche Gaines's outstanding work, Cryptanalysis: A Study of Ciphers
and Their Solution, first published in 1939. Gaines's
explanation is, in my opinion, still one of the best on this subject.
In these cryptograms, I've deliberately constructed both the message
and the keyword to be accessible by "cribs." These are useful, as confirmed
by several messages by solvers via private channel indicating they have
broken ciphers almost entirely by guessing the right "crib."
me to the Playfair cryptograms!***