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I'm studying the Kryptos sculpture with its cryptographic puzzles K1 to K4.

Similar to the "palimsest" keyword for K1, the keyword "abscissa" for K2 was determined by brute-force.

To better understand the puzzle as a whole and ultimately solve K4, it's important to understand how the "agent in the field" might have discovered these keywords.

One suggestion is that the keyword "abscissa" is derived from the plaintext of K1 which reads:


Which, given a sort of "cryptic crossword" reading can give you:

  1. Between "Subtle Shading And" -> "SSA"
  2. ... the ABSence -> "ABS"
  3. ... of Light (speed of light == "C" in physics) -> "C"
  4. ... lies the nuance of Iqlusion -> "I"

And with standard sort of anagram "fun", one comes up with "ABSCISSA."

Not very strong, but maybe believable.

Is there a better theory out there?

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I think the best theory is crib-dragging the phrase "virtuALLYINVISIBLE" from the morse code sections. This will line up with "itwastotALLYINVISIBLE" from K2 and reveal the entire keyword, repeating and removing any doubts.

Come to think of it, it may very well have been the intension of Sanborn to have us decode K2 first by this method, and then from K2's ending (IDBYROWS/XLAYERTWO) derive the word palimpsest, because that´s basically what it is. One text scraped away to make room for another text and hinted at by the use of "LAYER TWO".

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Dave, The kryptos yahoo list is nothing more than a longstanding crowd sourcing endeavour, and little to no thought is given to practical data mining needs.

I agree with your approach - making the info more accessible means useful results are more likely.

ABSCISSA This was derived using viginere, with the keyword virtuallyinvisible offset by three additional chars. In the case of the morse containing the keyword, 'e's are used (ie eeevirtuallyinvisible)

You will find ABSCISSA on the third line (ie line 1 of 'K2'.

PALIMPSEST A THEORY was put forward using palindromes to derive PALIMPSEST. The theory is incorrect however there are presently no other meaningful propositions for same in the public domain.

Good luck :)

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The Morse code letters that are palindromes are E,H,I,K,M,O,P,R,S,T,X. This may be the reason Kryptos is spelled with a K. I believe the list suggested the word. The palindromes in K4 are important to the solution.

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