July 2, 2009 — A couple of days ahead of the 233rd birthday of the United States of America, here's an interesting item from today's Wall Street Journal.
As far as scholars can tell, an enciphered letter received by President Thomas Jefferson in 1801 from his friend, Robert Patterson, had gone unsolved for over two centuries — until code-breaker Lawren Smithline took a shot at it in 2007.
Smithline, 36, a mathematician and now a professional cryptanalyst, recently published his solution. It's not quite the "perfect cipher" that the nineteenth-century puzzle's author thought it was: although quite possibly unbreakable in its time, it would have been impractical for everyday use as a quill-and-parchment system. Even though Patterson had a systematic method for sprinkling the ciphertext with numerous nulls, his cryptogram is readily identifiable as a transposition cipher.
Readers will find the content of the letter to be a paraphrased excerpt from a well-known document — one that was written largely by Jefferson himself.