Two Centuries On, a Cryptologist Cracks a Presidential Code

For more than 200 years, buried deep within Thomas Jefferson's correspondence and papers, there lay a mysterious cipher -- a coded message that appears to have remained unsolved. Until now.

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.

In this message, Mr. Patterson set out to show the president and primary author of the Declaration of Independence what he deemed to be a nearly flawless cipher. "The art of secret writing," or writing in cipher, has "engaged the attention both of the states-man & philosopher for many ages," Mr. Patterson wrote. But, he added, most ciphers fall "far short of perfection."

There is no evidence that Jefferson, or anyone else for that matter, ever solved the code. But Jefferson did believe the cipher was so inscrutable that he considered having the State Department use it, and passed it on to the ambassador to France, Robert Livingston.

The cipher finally met its match in Lawren Smithline, a 36-year-old mathematician. Dr. Smithline has a Ph.D. in mathematics and now works professionally with cryptology, or code-breaking, at the Center for Communications Research in Princeton, N.J., a division of the Institute for Defense Analyses.

After about a week of working on the puzzle, the numerical key to Mr. Patterson's cipher emerged -- 13, 34, 57, 65, 22, 78, 49. Using that digital key, he was able to unfurl the cipher's text:

"In Congress, July Fourth, one thousand seven hundred and seventy six. A declaration by the Representatives of the United States of America in Congress assembled. When in the course of human events..."

That, of course, is the beginning -- with a few liberties taken -- to the Declaration of Independence, written at least in part by Jefferson himself. "Patterson played this little joke on Thomas Jefferson," says Dr. Smithline. "And nobody knew until now."