from The New York Times
Sculptor Offers Another Clue in 24-Year-Old Mystery at C.I.A.
SECTION 4: UNSOLVED
Despite many attempts to decrypt it, the final section of the Kryptos sculpture remains unsolved.
The artist who created the enigmatic Kryptos, a puzzle-in-a-sculpture that has driven code breakers to distraction since it was installed 24 years ago in a courtyard at C.I.A. headquarters in Langley, Va., has decided that it is time for a new clue.
By 1999, nine years after it went up, Kryptos fans had deciphered three of the sculpture’s four messages — 865 letters punched through elegantly curved copper sheets that make up the most striking part of the work. (In fact, cryptographers at the National Security Agency cracked those messages in 1993, but kept the triumph to themselves.) The fourth and final passage, a mere 97 characters long, has thwarted thousands of followers ever since.
Jim Sanborn, the sculptor, having grown impatient with the progress of the fans and their incessant prodding for clues — and the misguided insistence by some that they had actually solved the puzzle — provided a six-letter clue to the puzzle in 2010. The 64th through 69th characters of the final panel, when deciphered, spelled out the word BERLIN.
Since then, the fans, many of whom keep up a lively online conversation, have come up empty-handed. And so Mr. Sanborn has decided to open the door a bit more with five additional letters, those in the 70th through 74th position.
They spell “clock.”
This means that the letters from positions 64 to 74 spell out two words: “Berlin clock.”
As it happens, there is a famous public timepiece known as the “Berlin clock,” a puzzle in itself that tells time through application of set theory. Its 24 lights count off the hours and minutes in rows and boxes, with hours in the top two rows and minutes in the two below.
When asked whether his new clue was a reference to this Berlin clock, Mr. Sanborn, sounding pleased, said, “There are several really interesting clocks in Berlin.”
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