GPDD JPLG EEHF BCAN HECD UECD EBAL HFBC AJAR HLEE AGBB SAFB ODFA JAPI AAEG FJBC HIBA AFMH FQBA EFDI BCAG EBGF JNOF DIBC MGHF NIGF TCEA RAFB CLHM NAGE BEHJ AECD DBKI DMBC ALAK BAOA DKBC AJAG BCEC AGJG NAAL HFAK IDMB CABI AABC IDQP CBCA ECDB KHKB OKAA BDQB
First I deleted all the spaces in the cryptotext and counted the occurences of each letter.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 34 27 19 15 16 14 12 11 9 8 7 6 5 5 4 4 3 2 1 1 1 0 0 0 0 0
Then I made a first guess what the substitution could be:
Code Letter ABCDEFGHIJKLMNOPQRSTUVWXYZ Real Letter ETAONRISHDLFCMUGPYWBVKXJQZThis led to the following decoded text:
IGOODGFINNSRTAEMSNAOVNAONTEFSRTAEDEYSFNNEITTWERTUORE
DEGHEENIRDTASHTEERCSRPTENROHTAEINTIRDMUROHTACISRMHIR
BANEYERTAFSCMEINTNSDENAOOTLHOCTAEFELTEUEOLTAEDEITANA
EIDIMEEFSRELHOCTAETHEETAHOPGATAENAOTLSLTULEETOPT
Next I looked for patterns that could be words. For example "TAE" occured seven times. Probably this was the word "THE" which meant that I should swap A and H. Or "TWERTU": Could it be "TWENTY"? I guessed so and swapped R with N and U with Y. Now I had
IGOODGFIRRSNTHEMSRHOVRHORTEFSNTHEDEUSFRREITTWENTYONE
DEGAEERINDTHSATEENCSNPTERNOATHEIRTINDMYNOATHCISNMAIN
BHREUENTHFSCMEIRTRSDERHOOTLAOCTHEFELTEYEOLTHEDEITHRH
EIDIMEEFSNELAOCTHETAEETHAOPGHTHERHOTLSLTYLEETOPT
Continuing in this way the correct substitution turned out to be
Code Letter ABCDEFGHIJKLMNOPQRSTUVWXYZ Real Letter ETHOSNAIRDFLMBYGUVWCPKXJQZwhich decoded the cryptotext to
AGOODGLASSINTHEBISHOPSHOSTELINTHEDEVILSSEATTWENTYONE
DEGREESANDTHIRTEENMINUTESNORTHEASTANDBYNORTHMAINBRAN
CHSEVENTHLIMBEASTSIDESHOOTFROMTHELEFTEYEOFTHEDEATHSH
EADABEELINEFROMTHETREETHROUGHTHESHOTFIFTYFEETOUT
Inserting spaces the result was
A GOOD GLASS IN THE BISHOP'S HOSTEL IN THE DEVIL'S SEAT TWENTY-ONE DEGREES AND THIRTEEN MINUTES NORTH-EAST AND BY NORTH MAIN BRANCH SEVENTH LIMB EAST SIDE SHOOT FROM THE LEFT EYE OF THE DEATH'S HEAD A BEE-LINE FROM THE TREE THROUGH THE SHOT FIFTY FEET OUT
Later I was told that this was a (slightly modified) text from Edgar Allan Poe's book "The Gold-Bug".
November 7, 1995
Mark Dettinger