A number of fun ciphers (Playfair, Bifid, Four Square, etc.) use
a “Polybius Square” to encrypt data. The standard
”Polybius Square” is a 5x5 box. In theory, though, the box
can be any size; for example you can create a smaller (4x4) or
bigger (6x6, 7x7, etc) “Square” or a “Rectangular Box” (4x6, 5x8,
etc). A limitation of the standard 5x5 “Polybius Square” is
that it only uses 25 of the 26 letters of the alphabet. However, if
you expand to a 6x6 box, we can now use all 26 letters as well as
the digits 0-9. For those of us who like puzzle caches, this means
we can encrypt numerical coordinates as well as text. It doesn't
really make the cipher any more difficult to break, just more time
consuming. Especially when there doesn't seem to exist a 6x6
Playfair decryption tool on the Web
Since most of us simply go to a decryption site to decipher a
standard Playfair cipher, I thought it would be fun to test
everyone's (or at least those willing to play) understanding of the
methodology behind Playfair by creating a 6x6 Playfair cipher that
will have to be solved by hand (until one of the savants writes a
program for it)
The standard “Polybius Square” also uses a keyword or
phrase to “shift” or “scramble” the letters. Rather than using a
simple keyword to shift the letters, I have “scrambled” the
alphabet to the ”Polybius Square” using a Pangram
(see Wikipedia). You’ll just have to figure out which one. In
addition, to correctly place the numbers 0-9 within the
“Polybius Square”, you will have to carry out a simple
conversion on the numbers below
1953 931 2484 1730 710 2260 1494 1251 242 501
Per a suggestion, I’ve added a blank 6x6 Polybius Square for you
to use as a guide as well as an example of what a completed 6x6
Polybius Square might look like
To make it even more fun, I have buried the coordinates within a
personal axiom which seems appropriate for this puzzle cache. The
letters of the axiom are alternated with the coordinates, so look
carefully. Be sure to remove the X's that were used to break up
break up double letter combinations. And since I was having trouble
getting a good signal at ground zero, I have also provided an
encrypted hint about the hide location. The coordinates should get
you pretty close, though
I have replaced lower case letters for I and O to avoid
confusion with one and zero
A0 W6 XK TL iS i6 J5 XK K1 4A Z4 24 RF E9 S5 PL 3Q 6E J6 W6
6H W3 oP BM 9H LQ 2Z ZW LT N3 XL KE 7S C6 XK KM 0i 3C JC BR E8 SB
LW 7K Si 36 HN 46 U2 1C 6V KL 4P 76 iH Q4 1W H1 0A 6W KL TM TL 3S
US JN TK L6 03 R3 CP XY KF 06 E6 79 SQ LH TL 7X 6C N2 WY NP BL 76
QD MT TL 30 6P Q3 TM KL
Have Fun! Hopefully I have come up with an encrypted puzzle that
even the Geocoin Secret Agent will find challenging!