I've always been one for solving puzzles and cracking codes, so recently I pulled the two together to invent what I naively thought would be a brand new kind of puzzle. I called it Quipher. But it turns out this puzzle has existed for centuries, and it's normally called a cryptogram or a cryptoquote. So, having reinvented the cryptogram, I got curious about the history of cryptograms (and how I'd missed it), and now I run a daily cryptogram puzzle with a bit more context. The story involves Edgar Allan Poe, a newspaper challenge and a club of enthusiasts who gave their favourite puzzle a rather grand nickname.
The premise is simple. A message has been disguised by swapping its letters for something else, and your job is to work out what it says. Today the cryptogram (sometimes called a cryptoquote) is a newspaper and puzzle-book staple. But people have been setting ciphers for each other to crack for nearly two centuries, and some of the earliest examples look a lot like the puzzles we solve now.
Edgar Allan Poe's cryptogram challenge
One of the first documented cryptogram crazes started in December 1839, when Poe was writing for the Philadelphia paper Alexander's Weekly Messenger. He invited readers to write something in English, swap the letters for arbitrary symbols, and send it in. He'd solve it.
They did. Between December 1839 and May 1840 the paper recorded 36 ciphers as received, and Poe printed a number of them with their solutions. He later claimed it was closer to 100, with only one he couldn't crack, so I'd take the bigger figure with a pinch of salt. Most of the ciphers were simple substitutions, which is the same basic puzzle as a modern cryptogram.
One reader sent this in March 1840:
D67ε;002)7.U )177¿3;007☞*D071☜.*¿0k2] 2☞242, ,8 2☞.*D-¿7 6*¿wl7 w2¿wU. lDk4;078 Ul.4 D67 ☜Dk .U4.☞;07·
Poe's solution was:
"The village of Greenville, Butler county, Alabama, is about one hundred and forty miles from the city of Mobile."
I love that it's just a slightly random sentence, disguised and posted off to see if Poe could crack it. And the readers were clearly enjoying the contest. One wrote in with another puzzle and said that if Poe solved it in the next issue, he'd have to call him invincible. So the rivalry between setter and solver was there from the start.
The Gold-Bug cipher and Sherlock Holmes: solving as a story
In 1843 Poe took the idea further with The Gold-Bug, which has an encrypted message at its centre:
53‡‡†305))6*;4826)4‡.)4‡);806*;48†8¶60))85;1‡(;:‡*8†83(88)5*†;46(;88*96*?;8)*‡(;485);5*†2:*‡(;4956*2(5*-4)8¶8*;4069285);)6†8)4‡‡;1(‡9;48081;8:8‡1;48†85;4)485†528806*81(‡9;48;(88;4(‡?34;48)4‡;161;:188;‡?;
There was no real secret being protected here. Poe built the cipher for his readers, and solving it was the entertainment. The character in the story counts how often each symbol appears, looks for repeated combinations and slowly assigns letters. The opening resolves to "A good glass in the bishop's hostel...", and the full message points towards buried treasure.
What matters for puzzle history is that Poe walks you through the reasoning as well as the answer. You're invited to follow along and have a go yourself.
Conan Doyle picked up the idea in 1903 with "The Adventure of the Dancing Men", published in The Strand Magazine. Instead of symbols, the cipher is a row of little stick figures chalked around a Norfolk manor house, and Sherlock Holmes cracks it by working out which figure turns up most often. It's the same route Poe's solver took, and the story is a great excuse to look at a cryptogram that doesn't look like letters at all.
The American Cryptogram Association and the Aristocrat of Puzzles
By the early twentieth century, recreational cryptography had a proper following. In the 1920s the magazine Detective Fiction Weekly ran cryptography articles by M. E. Ohaver, and in 1930 a group of enthusiasts formed the American Cryptogram Association (ACA).
Their main event was the simple substitution cryptogram, which they named the Aristocrat of Puzzles. That's where the term "Aristocrat cipher" comes from, and the name still survives in the organisation today. In February 1932 they published the first issue of their magazine, The Cryptogram, and it grew into a whole ecosystem of setters and solvers swapping puzzles. Modern ACA publications cover dozens of cipher types, including Patristocrats, transposition ciphers, null ciphers and Xenocrypts (cryptograms in languages other than English).
How to solve a cryptogram: why the simple version survived
With all those variations on offer, the basic substitution cipher puzzle has lasted remarkably well, and I think I know why. Say you're given this:
GSRH RH Z HVXIVG
At first you have almost nothing. But the repeated RH tells you the same two-letter word appears twice, short words narrow the options, and common letters hint at likely substitutions. One correct guess gives you letters elsewhere, those letters expose fragments of other words, and those words give you more letters. Then the puzzle hits a tipping point, and what looked unreadable a few minutes ago becomes:
THIS IS A SECRET
That gradual shift is the whole appeal. You don't need to know an obscure fact to solve it, because everything you need is already on the page. You just have to spot the pattern.
Codewords: the crossword-shaped cousin
If you grew up in the UK, you may know this idea better as a codeword puzzle, or a code cracker. It's a crossword-style grid with no clues, where every square holds a number from 1 to 26 and each number stands for one letter of the alphabet. You're usually given a few letters to start you off, and you work out the rest from the shapes of the words.
The difference from a cryptogram is the grid. In a codeword the words cross each other, so every letter you find has to make sense across and down at once, which gives you extra clues for free. By most accounts, codewords have been a fixture of British newspapers since around the 1980s.
It's the same core skill as a cryptogram, though: spotting patterns and using what you know to unlock what you don't.
Quipher: a daily cryptogram and quote puzzle
This is what I had in mind when I built Quipher, the daily cryptogram on Noodler. It borrows the numbers from codewords and the disguised sentence from the cryptogram. Each day there's a famous quote with the letters swapped for numbers, and your job is to decode the quote. I'm sure Poe would have found mine fairly gentle, but there's no punctuation and no hint about the category, so you're back to the same tools as the 1840 readers. A few cryptogram tips to get you started:
Short words first: a single letter is almost always "A" or "I", and two-letter words are a small set you'll soon know by heart.
Repeated patterns: a number that keeps turning up is a good candidate for a common letter like E or T.
Word shapes: a double letter or a familiar ending can unlock a whole chunk at once.
If you miss a day, the Past Quiphers archive lets you replay old puzzles, and they're still fully scrambled when you open them. Quipher is still in progress, and I'll be tweaking it and adding to Noodler as I go. (Yes, the name is a bit of a mouthful, and I'm sticking with it anyway.)
Nearly two centuries of puzzling
The technology has changed a lot since Poe waited for readers to post their handwritten ciphers to Philadelphia. The game hasn't. A setter takes some ordinary language and disguises it, and a solver hunts for repetitions, frequencies and patterns until the words start to reappear. In 1840 people posted ciphers to Poe to see if they could stump him, and in 1930 people formed a club to do much the same thing.
The secret was never really the point. The fun is in finding it.
Sources
Puzzles Again (Edgar Allan Poe Society of Baltimore)
Edgar Allen Poe and Cryptography (Trinity College Computer Science)
The Adventure of the Dancing Men (The Arthur Conan Doyle Encyclopedia)