January 20, 2021

Poe's Secrets

Writer Edgar Allan Poe (1809-1849) is famous for his short stories of the mysterious and the macabre. Poe's tale "The Gold-Bug," published in 1843, is sometimes cited as one of the best works of fiction that turn upon a secret message.

"The Gold-Bug" is about a secret message written in invisible ink on a scrap of parchment. The deciphered message leads to a buried chest filled with fabulous treasure. Here's the coded message that Poe included in his story:


The clever treasure seeker in story, William Legrand, assumed that symbols stood for letters of the alphabet, with no spaces left between the words of the message. He noticed that the character "8" appears 33 times, far more often than any other character. In the English language, the letter that occurs most often is "e."

Starting with that clue, he went on to look for combinations of three characters that might represent "the"—a very common word in English. Legrand could then guess that the semicolon represents "t" and 4 represents "h."


Following such hints, Legrand deciphered the secret message. Clues contained in the mysterious message eventually led him to a fortune in gold and jewels.

Poe had a longstanding interest in cryptology. When he for a short time became editor of Graham's Lady's and Gentleman's Magazine in Philadelphia, he offered to solve cryptograms sent to him by readers and, while waiting for responses, wrote an essay about secret writing for the July 1841 issue of the magazine.

When Poe ended the contest 6 months later, he claimed to have solved the 100 or so legitimate ciphers that readers had submitted. In his final "addendum" on the topic, published in the December issue, Poe included two ciphers from "a gentleman whose abilities we very highly respect." He attributed the ciphers and accompanying notes to W.B. Tyler and challenged readers to solve the puzzles. Poe never published the solutions.

No one seemed to have paid much attention to the ciphers until 1985. That's when Poe scholar Louis A. Renza suggested in an essay, titled "Poe's Secret Autobiography," that Tyler and Poe were the same person.

English professor Shawn Rosenheim took up Renza's theory and, in his 1996 book The Cryptographic Imagination: Secret Writing from Edgar Poe to the Internet, furnished additional circumstantial evidence pointing to Poe as the author of the two ciphers.

Meanwhile, in 1992, intrigued by Rosenheim's ongoing research on the topic, Terence Whalen took a break from working on his dissertation to tackle the puzzle. He solved the first of Tyler's cryptograms, which consisted of a long string of various typographic symbols.


The key to the solution was Whalen's recognition that the three-symbol pattern ", † § "—repeated seven times in eight lines—represents the word "the."

The deciphered passage proved to be lines from the 1713 play Cato, a Tragedy by English essayist Joseph Addison (1672-1719). Whalen's solution, however, did not settle the question of who created the cipher.

The second cipher, which used several different symbols for each English letter in the text, was much more difficult.


Determined to obtain a solution, Rosenheim offered a prize of $2,500 for deciphering the cryptogram. The contest received a substantial boost in 1998 when Jim Moore of Bokler Software, which builds cryptographic components for software developers, created a website devoted to the puzzle.


Rosenheim and Moore fielded hundreds of inquiries from around the world. The puzzle was finally solved in July 2000 by Gil Broza, a software engineer in Toronto.

It turned out that the number of different symbols for a given letter depended on the relative frequency with which that letter appears in English text. So, there were two symbols standing for "z" and 14 symbols for "e." Given the brevity of the cipher, would-be sleuths couldn't count on applying information about letter frequencies to crack the code.

Broza assumed that the symbols in the cryptogram were properly broken up into English words and proceeded from there, eventually using a computer to check for patterns and sort through various possibilities.

Broza's solution revealed that the original cipher contained more than two dozen mistakes, which had been introduced by the typesetter or the puzzle's originator. The deciphered text begins, "It was early spring, warm and sultry glowed the afternoon. The very breezes seemed to share the delicious languour of universal nature,…"

That certainly doesn't sound like Poe, but the text echoes themes that he favored. The passage is probably taken from some unknown novel or story of the period, Rosenheim said. It's still possible, though not certain, that Poe himself composed both ciphers.

There is something mysterious even in the decrypted cipher, Rosenheim added, not only because we do not know who enciphered it but also because it reminds us of the uncanny and limited immortality writing sometimes affords.

Originally posted November 13, 2000

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