Cryptanalysis 3: Lord Bacon's Cipher Mystery Cache
Cryptanalysis 3: Lord Bacon's Cipher
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Difficulty:
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A continuation of the Cryptanalysis series, the solution and
reading of cryptic messages. Finders during the first week will get
special recognition among the “one week wonders.” After one week,
the method for solution will be posted along with an example.
As I study cryptanalysis and learn more about ciphers, I’m
sometimes amazed at how craftily messages can be concealed in what
looks like plain old text. Cryptanalysis 1 was one example. This
next cipher is another. The cache is not at
the posted coordinates, but within 1 mile.
9/3/05: End of week one. One team found the cache in the
first week. Congratulations to the "one week wonders:"
mtmitchellbound; fishnfla solved the puzzle as well. These guys did
some impressive Internet research & detective work to solve it
before the method was revealed. Now it's time to post the method
for solution....
Cryptanalysis 3: Lord Bacon's Cipher
Sir Francis Bacon (1561-1626) was Lord Chancellor of England under
Queen Elizabeth I. Some people believe he was also the true author
of some works traditionally attributed to William Shakespeare. Lord
Bacon devised a cipher for the preservation of historical secrets.
It's technically a form of steganography, with which even the
physical presence of a secret message is concealed. It would be
considered a combination of concealment cipher (like the Null
Cipher) and substitution cipher (like the Caesar Cipher).
Two fonts of type are required, the letters of one font differing
very slightly from those of the other font. Bacon called them
A-font and B-font, using the first two letters of his name. In
creating his cipher alphabet, he substituted combinations of A and
B in groups of five for each letter:
Lord
Bacon's Alphabet
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This was a pretext for binary code. Note that "I" & "J" as well
as "U" & "V" are combined, making a 24 letter alphabet.
In practice, the encipherer must be able to control the subtleties
in printing each letter of text with slight variations using the
pattern set forth in the above alphabet. This can be done, for
example, by interchanging regular type (the A-font) and italic type
(the B-font). Or, for a more discernible example, the following
uses lowercase letters for the A-font and capitals for the
B-font:
Cipher
Example
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Rearranging the letters into groups of five, and substituting 'a'
for lowercase letters and 'b' for capitals yields:
As one may see, the text which conceals the hidden message is
irrelevant and may say anything, including information contrary to
the true secret message.
While the best concealment ciphers should go undetected by everyone
but the intended recipient by blending with normal text, the text
in the above example as well as in the puzzle below was
intentionally made to stand out a bit. We're limited by the clarity
of our computer screens in examining these puzzles, and I didn't
want the important details to be missed because of this
limitation.
For the story so far, see
Cryptanalysis 1 and
Cryptanalysis 2.
With your help in deciphering 1GeoWulf’s secret messages, your
anonymous partner in Colorado is staying one step ahead of the
geocacher Numismatist. He (or she, you still don’t know which) has
beaten Numismatist to two of 1GeoWulf’s caches and retrieved an
ancient Roman coin from each. We now know that 1GeoWulf (AKA Jacob
Rabon), before his geocaching days, was a coin dealer and owner of
“12 Caesars Coins.” His business, however, seems to be closed and
the office at the address shown on his business card is vacant.
Your partner’s detective work within the Leadville coin-collecting
community has revealed that Jacob Rabon was the major supplier to
collectors of the Twelve Caesars coins, the ancient Roman coins
issued by Julius Caesar and the first eleven rulers of the Roman
Empire through 96 A.D.
For collectors of ancient coins, obtaining one coin in very good
condition issued by each of the twelve Caesars can be a long-term
and often expensive goal. Locally, Jacob Rabon was the authority on
building a collection of the Twelve Caesars. He organized a club of
coin collectors, to whom he supplied most of the coins. While the
club continues to meet monthly, he is no longer active with them.
Your partner attended a meeting of the club and confirmed that the
coins pulled from the two geocaches were issued by two of the
Twelve Caesars, Julius Caesar and Vitellius. In fact, they were two
of the rarer issues among the Twelve Caesars and quite
valuable.
It was after the meeting that your partner noticed one of the club
members getting into a car with a geocaching sticker on the back.
Could this be Numismatist?
After following the guy for a few days, your partner was able to
establish where he dines frequently (always alone), and recover a
letter from his garbage written by Jacob Rabon. It would appear
that Numismatist may be a Mr. Hillshire and is a coin dealer
himself.
Additional Hints
(Decrypt)
[For locating the cache:] Pbhag sebz gur fbhgu. Bire abg haqre.
Treasures
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