After over 200 years, cryptographs have finally cracked a cyper Thomas
Jefferson used in correspondance with a friend.

"The cryptic message was sent to President Jefferson in December 1801 by
his friend and frequent correspondent, Robert Patterson, a mathematics
professor at the University of Pennsylvania. President Jefferson and Mr.
Patterson were both officials at the American Philosophical Society -- a
group that promoted scholarly research in the sciences and humanities --
and were enthusiasts of ciphers and other codes, regularly exchanging
letters about them."

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