Voynich Manuscript, Beinecke Rare Book and Manuscript Library, Yale University.
Voynich Manuscript, Beinecke Rare Book and Manuscript Library, Yale University.

5 Historic Codes Yet to Be Cracked

Voynich Manuscript, Beinecke Rare Book and Manuscript Library, Yale University.
Voynich Manuscript, Beinecke Rare Book and Manuscript Library, Yale University.

Edgar Allan Poe, in a July 1841 article for Graham's Magazine, wrote that while people tend to think it's a relatively simple thing to create an uncrackable secret code, in fact "it may be roundly asserted that human ingenuity cannot concoct a cipher which human ingenuity cannot resolve." That was easy for him to say. Shortly after his premature death, Poe's friend the Rev. Warren H. Cudworth recalled that the author's ability to "unravel the most dark and perplexing ciphers was really supernatural." The rest of us get stumped sometimes. Here are five codes and ciphers that have stymied human ingenuity for decades, centuries, even millennia.


Nude women dealing with pipes.Voynich Manuscript, Beinecke Rare Book and Manuscript Library, Yale University. (The History Blog)

The Voynich Manuscript has been puzzling emperors, antiquarians and cryptologists for at least 400 years. It's an illuminated manuscript of 240 vellum pages written by an unknown author in an unknown language. Vibrant illustrations of plants and astronomical and astrological charts suggest the volume may be an alchemical, magical, or scientific text. The calfskin pages were radiocarbon dated to between 1404 and 1438. While the iron gall ink has not been dated, since there is no erased earlier writing on the pages, it's likely the manuscript was written around the same time.

Researchers believe Holy Roman Emperor Rudolph II (1576-1612) acquired the manuscript in the late 16th century and gave it to his personal physician and pharmacologist Jacobus Sinapius to see if he could make heads or tails of it. He couldn't. Neither could Czech alchemist Georg Baresch, Bohemian physician Johannes Marcus Marci and Jesuit polymath Athanasius Kircher. After Kircher got the book from Marci in 1665, the manuscript disappears from the historical record until 1912 when antique book dealer Wilfrid Voynich found it in a chest of books the Jesuits were trying to sell at the Villa Mondragone in Frascati, Italy. Voynich would dedicate the rest of his life to deciphering the manuscript. Although he failed, at least his efforts secured him the naming rights.

They also garnered him posthumous accusations of fraud as some people believed the whole book was a hoax devised by Voynich himself. Radiocarbon dating put paid to that theory, as the odds of anyone finding that much fresh, unused 15th century vellum to cover with fantastical writing and drawing are slim to none. Professional codebreakers in both World Wars and one Cold one tried their hand at cracking the Voynich code without success. (You can read mental_floss's story about recent attempts to crack it here.)

It's not just the writing that has proven impossible to crack: some of the drawings are ciphers too. There are 113 unidentified plant species depicted in the manuscript, and nobody knows what the female nudes striking curious poses in bodies of water or with odd pipe systems are supposed to mean.

Do you think you're better than the imperial court of Rudolf II, the greatest cryptographers of the 20th century and pretty much everyone else? You can try your hand at cracking the Voynich Manuscript on the website of Yale University's Beinecke Rare Book and Manuscript Library.


PapyrusOxyrhynchus 90. "The Oxyrhynchus Papyri," Grenfell and Hunt, 1898.

In 1896, archaeologists Bernard Pyne Grenfell and Arthur Surridge Hunt discovered thousands of papyrus fragments in a garbage dump outside Oxyrhynchus, Egypt. Preserved by the dry desert heat, the papyri recorded details of daily life (receipts, insurance claims, loan notes, personal letters), fine literature (large sections of lost Euripides plays, summaries of seven lost books by Livy, a poem by Sappho), and scriptures—gospels both canonical and apocryphal—from the 1st to the 6th century CE.

Papyrus 90 is one of the mundane daily life records, a receipt for a deposit of wheat in the public granary dating to 179-80 CE. What makes it not mundane are the last two lines. They're written in Greek characters like the rest of the papyrus, but they're not Greek words. Grenfell and Hunt noted when they published the papyrus that it wasn't a Graecized version of Demotic script (the Egyptian "document writing" language) either. It appears to be a cryptogram, some wheat deposit intelligence that demanded secrecy.

A transcription of the text is available for the intrepid Greek scholar/cryptographer here.


Charles I and Henrietta Maria Holding a Laurel Wreath, 1632, by Anthony vanDyck. Archbishop's Castle and Gardens, Kroměříž. (The History Blog

King Charles I of England had many secrets to keep and many enemies to keep out of his secrets. Much of his correspondence was peppered with ciphers to keep prying Parliamentarian eyes out of his business. Charles's ciphers kept some secrets so ably that historians didn't realize until a few years ago that a) he ever talked dirty, and b) he planned "a swiving" (an obscene word for sex) with the redheaded stepdaughter of one of his courtiers while imprisoned in Carisbrooke Castle in 1648.

During the First English Civil War (1642–1646), he and his beloved wife Henrietta-Maria were apart for long stretches. In the beginning she was in The Hague trying to drum up political support for the Royalist cause and to hock the Crown Jewels to fund her perpetually-broke husband's war. By March of 1645, with the tides of war having turned against them, Henrietta-Maria was back in her hometown of Paris.

Throughout their separation they wrote to each other assiduously, and they weren't whispering sweet nothings. Henrietta was deeply involved in her husband's governance and for all intents and purposes was a continental branch of Charles I's court. These letters were replete with political machinations, military plans, and perhaps most relevantly for a Protestant England that was deeply suspicious of the Catholic Henrietta-Maria, promises to liberalize England's anti-Catholic laws.

On March 5, 1645, Charles sent a new cipher to Henrietta-Maria via a trusted courier named Pooly. A month later in a letter to his wife dated April 8, he used the cipher:

In a word, when I know none better (I speak not now in relation to business), then 3 9 8 270 55 5 7 67 18 294 35 69 16 54 6 38 1 67 68 9 66: thou mayest easily judge how thy conversation pleased me.

[note] The little that is here in cipher is in that which I sent to thee by Pooly.

After the Battle of Naseby on June 14, 1645, Charles and Henrietta's correspondence was confiscated and published by the Parliamentarians. His letter of March 5 was revealed to be something of a bombshell: He authorized her to promise in his name to anyone useful that "I will take away all the penal laws against the Roman Catholicks in England as soon as God shall enable me to do it so al by their means I may have so powerful assistance as may deserve so great a favour and enable me to do it."

So that April cipher could be an expression of affection or intimacy (he probably wasn't talking about swiving her, though), or it could have been a whole other kind of conversation, like some payoff from that promise, that pleased King Charles. We won't know until someone cracks it.


The Dorabella Cipher in Elgar's own hand. (The History Blog)

Composer Edward Elgar may be best known today as the accompaniment to every graduation ceremony with Pomp and Circumstance, but he was also a fan of cryptographic arts. He expressed his ciphering talent in an addendum to a letter his wife wrote on July 14, 1897. The letter was a thank you note to the Penny family at whose home the Elgars had just spent a convivial few days. Elgar had struck up a friendship with the daughter of the family, Dora Penny, and he added a postscript to his wife's letter directed to Dora.

At first glance it looks like group of squiggles at different angles reminiscent of the universal comic book symbol for dizziness, but each character is actually composed of one, two, or three semicircles tilted in eight different directions. Dora couldn't crack it, so she put the letter in a drawer for the next 40 years until she published it in her memoirs in 1937. Since then, people have tried to solve the Dorabella Cipher with some pretty wacky results.

Tim S. Roberts thinks he's cracked it with a simple substitution cipher (you can find a PDF explaining his solution here):

"P.S. Now droop beige weeds set in it – pure idiocy – one entire bed! Luigi Ccibunud luv'ngly tuned liuto studio two."

The subject, Roberts believes, refers to an earlier letter or conversation in which Edward and Dora discussed his excessive pruning of his garden. Without this extremely obscure conversation, the solution makes no sense at all, and frankly, even with it only the first sentence makes sense. He also had to jiggle things to make them fit. Some parts are straight substitution, others require letters to be switched or added. He only glosses over what "Ccibunud" might mean, saying that Elgar loved the Italian composer Luigi Cherubini growing up, and Dora Penny was said to have had a stutter, so Elgar was teasing her over her pronunciation of an Italian composer that apparently she introduced a random d into. There's also no character for the i in studio. He just put that in to make it form a word.

When the Elgar Society held a Dorabella Cipher Competition in 2007 to celebrate Elgar's 150th birthday (and again the next year), none of the solutions were accepted because although several seemed to be very well reasoned, in the end, "the results read as a disconnected chain of bizarre utterances, such as an imaginative mind could conjure up from any group of random letters." So far all the proposed solutions seem to fall into this category. And there's one final twist: A key created by Elgar in the 1920s—which, according to New Scientist, appeared in an exercise book and "listed the symbols used in the Dorabella cipher matched against the letters of the alphabet"—doesn't yield anything that makes sense.


Carrier Pigeon NURP 40 TW 194's final message // The History Blog

In 1982, David and Anne Martin found the remains of a bird during renovation of the fireplace of their home in Bletchingley, Surrey. One of its skeletonized legs had a red plastic capsule attached to it, marking it as a World War II military carrier pigeon that picked the wrong roost on its way to deliver a message and died in the chimney. Inside the capsule was the original coded message—27 groups of five letters with some numerals at the end—written on a scroll the size of a rolling paper.

It took years before anyone in government could be persuaded to take a look at the cipher. In 2010, experts at Bletchley Park, a museum that was the headquarters of British Intelligence's codebreakers during World War II, finally checked it out. They were not able to crack it, but they did discover that it must have been an important missive. None of Bletchley Park's classified MI6 pigeons carried coded messages during the war. Given Bletchingley's location half way between Normandy and Bletchley Park and just five miles from Field Marshal Montgomery's headquarters at Reigate where the D-Day landings were planned, it's possible that Pigeon NURP 40 TW 194 was carrying very sensitive information indeed.

A few weeks after the story broke, the media reported that Ontario history buff Gord Young claimed to have cracked the code thanks to his great-uncle's World War I Royal Flying Corp aerial observers book. His solution was rough around the edges, however. He wasn't able to decipher some of it, and several of the 27 groups he interpreted as improvised acronyms with no antecedents in the military record. He may have misinterpreted some of the letters—mistaken a U for a W, for instance—and there are some painfully awkward, redundant phrases like "Determined where Jerry's headquarters front posts. Right battery headquarters right here. Found headquarters infantry right here. Final note, confirming, found Jerry's whereabouts." That's a lot of repetitive verbiage to take up space on a cigarette paper.

Bletchley Park didn't think the solution was the right one. Then, the cryptological world discovered that Young had never intended to present an actual answer—he was just trying to help move the process along. So until a World War II code book is found with a proper key, Bletchley Park doesn't think anyone is going to be able to crack the pigeon's code.

Sergeant Marshall/Department of Defense, NARA // Public Domain
Would You Be Able to Pass a World War I Military Literacy Test?
Sergeant Marshall/Department of Defense, NARA // Public Domain
Sergeant Marshall/Department of Defense, NARA // Public Domain

Though reading and writing might not come to mind as the first requirement for trench warfare, during the early 20th century, the U.S. Army became increasingly concerned with whether or not its soldiers were literate. Thousands of World War I soldiers couldn't read printed directions on basic military tasks. The Army didn't implement its first major literacy program until the 1940s, but literacy tests were included in a battery of psychological evaluations World War I recruits went through to determine their mental fitness and intelligence, as the blog Futility Closet recently highlighted.

These unconventional literacy tests largely took the form of a yes or no questions with obvious answers, according to the 1921 report from the U.S. Surgeon General, Psychological Examining in the United States Army. Edited by pioneering intelligence-testing psychologist Robert Yerkes, who developed the military's first psychology exams for new recruits (and was also famous for his support for eugenics), the volume is a lengthy compilation of all of the methods the U.S. Army used to test the intelligence of its future soldiers. Many of these tests are now considered racist and culturally biased—some of the "intelligence" testing questions required recruits to know things like what products Velvet Joe (a figure used in tobacco campaigns) advertised—but some of the literacy questions, in particular, simply come off as weird in the modern era. Some are downright existential, in fact, while others—"Is a guitar a disease?"—come off as almost poetic.

A long questionnaire to test literacy, including questions like 'Is coal white?'
Psychological Examining in the United States Army, Google Books // Public Domain

One test, the Devens Literarcy Test, asked recruits questions like "Is genuine happiness a priceless treasure?" and "Does success tend to bring pleasure?" Another section of the test asked "Do boys like to play?" and "Do clerks enjoy a vacation?"

Other questions seem like they're up for debate, like "Are painters ever artless individuals?" and "Is extremely athletic exercise surely necessary?" Surely the answers to questions like "Should criminals forfeit liberty?" and "Is misuse of money an evil?" depend on the opinions of the reader. The answer to "Do imbeciles usually hold responsible offices?" might be different depending on how the person feels about their Congressional representative, and could surely be the spark for an hour-long argument at most dinner parties.

Still others are tests of cultural knowledge, not reading skill—a major modern criticism of Yerkes's work. Despite being arguably a pretty literate person, I certainly don't know the answer to the question "Do voluntary enlistments increase the army?" A question like "Are 'diminutive' and 'Lilliputian' nearly identical?" isn't exactly a test of literacy, but a test of whether or not you've read Gulliver's Travels, which doesn't exactly seem like a necessity for military success.

Luckily, some of the questions are pretty obvious, like "Is coal white?" That one I can answer. The full list of questions used in the various versions of the Devens test is below for you to test your own Army-level literacy.

  • Do dogs bark?
  • Is coal white?
  • Can you see?
  • Do men eat stones?
  • Do boys like to play?
  • Can a bed run?
  • Do books have hands?
  • Is ice hot?
  • Do winds blow?
  • Have all girls the same name?
  • Is warm clothing good for winter?
  • Is this page of paper white?
  • Are railroad tickets free?
  • Is every young woman a teacher?
  • Is it always perfect weather?
  • Is the heart within the body?
  • Do clerks enjoy a vacation?
  • Is the President a public official?
  • Would you enjoy losing a fortune?
  • Does an auto sometimes need repair?
  • Is it important to remember commands?
  • Are avenues usually paved with oxygen?
  • Do we desire serious trouble?
  • Is practical judgment valuable?
  • Ought a man's career to be ruined by accidents?
  • Do you cordially recommend forgery?
  • Does an emergency require immediate decision?
  • Should honesty bring misfortune to its possessor?
  • Are gradual improvements worth while?
  • Is a punctual person continually tardy?
  • Are instantaneous effects invariably rapid?
  • Should preliminary disappointment discourage you?
  • Is hearsay testimony trustworthy evidence?
  • Is wisdom characteristic of the best authorities?
  • Is extremely athletic exercise surely necessary?
  • Is incessant discussion usually boresome?
  • Are algebraic symbols ever found in manuals?
  • Are tentative regulations ever advantageous?
  • Are "diminutive" and "Lilliputian" nearly identical?
  • Is an infinitesimal titanic bulk possible?
  • Do all connubial unions eventuate felicitously?
  • Is a "gelatinous exaltation" ridiculous?
  • Are "sedate" and "hilarious" similar in meaning?
  • Is avarice sometimes exhibited by cameos?
  • Can a dog run?
  • Is water dry?
  • Can you read?
  • Do stones talk?
  • Do books eat?
  • Do cats go to school?
  • Are six more than two?
  • Is John a girl's name?
  • Are there letters in a word?
  • Is your nose on your face?
  • Can you carry water in a sieve?
  • Do soldiers wear uniforms?
  • Does it rain every morning?
  • Are newspapers made of iron?
  • Are "forward" and "backward" directions?
  • Do many people attend motion-picture theatres?
  • Do handkerchiefs frequently injure human beings?
  • Do magazines contain advertisements?
  • Are political questions often the subject of debates?
  • Are empires inclosed in envelopes?
  • Are members of the family usually regarded as guests?
  • Is genuine happiness a priceless treasure?
  • Do imbeciles usually hold responsible offices?
  • May chimneys be snipped off with scissors?
  • Is moderation a desirable virtue?
  • Are apish manners desired by a hostess?
  • Do conscientious brunettes exist?
  • Do serpents make oblong echoes?
  • Do voluntary enlistments increase the army?
  • Is hypocrisy approved by honest men?
  • Is virile behavior effeminate?
  • Do alleged facts often require verification?
  • Do pestilences ordinarily bestow great benefit?
  • Are painters ever artless individuals?
  • Do the defenders of citadels sometimes capitulate?
  • Do physicians ameliorate pathological conditions?
  • Is embezzlement a serious misdemeanor?
  • Do vagrants commonly possess immaculate cravats?
  • Are "loquacious" and "voluble" opposite in meaning?
  • May heresies arise among the laity?
  • Are piscatorial activities necessarily lucrative?
  • Do tendrils terminate in cerebral hemorrhages?
  • Does a baby cry?
  • Can a hat speak?
  • Do hens lay eggs?
  • Is a stone soft?
  • Is one more than seven?
  • Do the land and sea look just alike?
  • Are some books black?
  • Does water run up hill?
  • Are stamps used on letters?
  • Do 100 cents make a dollar?
  • Are we sure what events will happen next year?
  • Do ships sail on railroads?
  • Do stones float in the air?
  • May meat be cut with a knife?
  • Are ledges common in mountain districts?
  • Does success tend to bring pleasure?
  • Are diamonds mined in mid-ocean?
  • Is misuse of money an evil?
  • Should criminals forfeit liberty?
  • Is special information usually a disadvantage?
  • Are attempted suicides always fatal?
  • Are exalted positions held by distinguished men?
  • Does confusion favor the establishment of order?
  • Is a civil answer contrary to law?
  • Is a dilapidated garment nevertheless clothing?
  • Are textile manufacturers valueless?
  • Do thieves commit depredations?
  • Does close inspection handicap accurate report?
  • Do transparent goggles transmit light?
  • Do illiterate men read romances?
  • Is irony connected with blast furnaces?
  • Do avalanches ever descend mountains?
  • Are scythes always swung by swarthy men?
  • Do pirates accumulate booty?
  • Are intervals of repose appreciated?
  • Are intermittent sounds discontinuous?
  • Is an avocational activity ordinarily pleasurable?
  • Are pernicious pedestrians translucent?
  • Are amicable relationships disrupted by increased congeniality?
  • Are many nocturnal raids surreptitiously planned
  • Are milksops likely to perpetrate violent offenses?
  • Are "precipitancy" and "procrastination" synonymous?
  • Is snow cold?
  • Can a dog read?
  • Do houses have doors?
  • Has a horse five legs?
  • Are three more than ten?
  • Do mice love cats?
  • Does a hat belong to you?
  • Do animals have glass eyes?
  • Should fathers provide clothing for children?
  • Is it true that lead is heavy
  • Do poor men have much money?
  • Is summer colder than winter?
  • Can a horse tell time by a watch?
  • Is a city larger than a country town?
  • Does Christmas ever fall on Tuesday?
  • Do Christians often overlook faults?
  • Are difficult problems easily solved?
  • Do convicts sometimes escape from prison?
  • Should the courts secure justice for everybody?
  • Are scoundrels always intoxicated?
  • Is a guitar a kind of disease?
  • Do jugglers furnish entertainment?
  • Should we build on insecure foundations?
  • Do annual conventions take place biweekly?
  • Does persistent effort favor ultimate success?
  • Is a shrewd man necessarily admired?
  • Is manual skill advantageous?
  • Are elaborate bonnets inexpensive?
  • Are petty annoyances irritating?
  • Are false arguments valid?
  • Do you approve of ruthless massacres?
  • Do blemishes occur in complexions?
  • Is air found in a complete vacuum?
  • Do robins migrate periodically?
  • Are weird tales sometimes gruesome?
  • Do felines possess locomotor appendages?
  • Do demented individuals frequently have hallucinations?
  • Are laconic messages sometimes verbose?
  • Are perfunctory endeavors usually efficacious?
  • Would a deluge extinguish a smouldering trellis?
  • Are devastated suburbs exhilarating vistas?
  • Are "contingent" and "independent" alike in meaning?

[h/t Futility Closet]

10 Not-So-Small Facts About the Volkswagen Beetle

While Volkswagen has announced—for a second time—that it's going to cease production on the Beetle, people are still singing the praises of the quirky little car. Here are 10 not-so-small things you need to know about the German car that was once named one of the top four cars of the century.


Adolf Hitler checks out a VW Beetle
Getty Images

It’s long been said that Adolf Hitler was the man behind the Beetle, and that’s sort of true. The dictator wanted German families to be able to afford a car, so he enlisted automaker Ferdinand Porsche (yes, that Porsche) to make “the people’s car.” But the basis for the Beetle had been around since long before Hitler’s demand; the Bug was heavily influenced by Porsche's V series. Rumors that Hitler directly designed the car are probably false; though he was the one who reportedly said that the car should look like a beetle, because “You only have to observe nature to learn how best to achieve streamlining,” it’s likely that he was regurgitating something he had read in an automotive magazine. Still, one thing is for certain: Hitler himself placed the cornerstone for the Porsche factory in Wolfsburg, Germany.


Perhaps still wary of anything imported from Germany, Americans shunned the Beetle when it was introduced in the States in 1949: Only two were sold in the first year. But after that, sales grew quickly. By the 1960s, hundreds of thousands of Bugs were sold every year, topping out at 570,000 in 1970.


A pink VW Beetle

We have the public to thank for the car’s distinctive nickname. Originally known as the Volkswagen Type 1, the car’s curves and rounded top led to its later, insect-like moniker. Volkswagen must have realized they had a good thing on their hands, because they started referring to the car as the VW Beetle in the late 1960s.


The UK and the U.S. aren’t the only countries that bestowed a new name on the Volkswagen Type 1. In France, it's called Coccinellewhich means ladybug. It's Maggiolino and Fusca in Italy and Brazil, respectively, both of which mean "beetle." Mexico calls it Vocho; it's Peta (turtle) in Bolivia; and Kodok (frog) in Indonesia. 


In 1999, Advertising Age declared the car's not-so-small ad campaign to be the best campaign of the last 100 years, besting Coca-Cola, Marlboro, Nike, and McDonald’s. The quirky concept and copy—which, according to Advertising Age, “Gave advertising permission to surprise, to defy and to engage the consumer without bludgeoning him about the face and body”—was a game-changer for the entire industry.

The "Think Small" line and accompanying self-deprecating copy was written by Julian Koenig, who was also responsible for naming Earth Day and coming up with Timex’s “It takes a licking and keeps on ticking” tagline. He’s also half-responsible for daughter Sarah Koenig, whom you may know from NPR’s This American Life and Serial.


Herbie the Love Bug

Because of their distinctive aesthetic, VW Bugs have been associated with everything from the Beatles to Transformers. A few highlights:

  • The Beetle with the license plate “LMW 28IF” on the cover of The Beatles' Abbey Road album was sold at an auction for $23,000 in 1986. It is now on display at Volkswagen's AutoMuseum at the company’s headquarters in Wolfsburg, Germany.
  • The Fremont Troll sculpture in Seattle, a huge statue lurking under the Aurora Bridge, clutches an actual VW Beetle. An in-progress picture shows that the car was once red. It also once contained a time capsule of Elvis memorabilia, which was stolen.
  • The Herbie the Love Bug series was a big hit for Disney in the late 1960s and early 1970s. One of the original Herbies sold for $126,500 at an auction in 2015.
  • In the original Transformers cartoon, Bumblebee transformed from a VW Bug. The car was changed to a Camaro for the live-action movies.


The so-called “blumenvasen,” a small vase that could be clipped to the dashboard, speaker grille, or windshield, was porcelain when it was originally offered. The nod to flower power became such a symbol of the car that it was incorporated into the 1998 redesign. Sadly, it didn’t make the cut for the most recent overhaul: The vase was eliminated in 2011 by marketing execs apparently seeking to make the car more male-friendly.


When the millionth VW Beetle rolled off the line in 1955, the company capped the achievement by plating the car in gold and giving it diamante accents. They also created a Bug with a wicker body in collaboration with master basket-maker Thomas Heinrich.


After WWII, the VW factory in Wolfsburg, Germany, was supposed to be handed over to the British. No British car manufacturer wanted to take responsibility for the company, though, saying that "the vehicle does not meet the fundamental technical requirement of a motor-car," "it is quite unattractive to the average buyer," and that "To build the car commercially would be a completely uneconomic enterprise." Whoops.


The last VW Bug
Getty Images

Beetle #21,529,464—the one celebrated by the mariachi band—is now at Volkswagen's AutoMuseum.


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