An (Almost) Comprehensive History of Rat Kings

Musées of Strasbourg, M. Bertola
Musées of Strasbourg, M. Bertola

Behold the rat king!

A ball of furry fury, a rat king occurs when the tails of rodents become twisted, wrapped, and warped into a knot so impossible that not even the world's most loyal Boy Scout could untangle it. Rat kings have been reported since the mid-16th century (almost entirely within Germany), and everything about them—from their name, to their cause, to their very existence—remains suspended in mystery.

To start, the origin of the term rat king is hazy. It may be a mistaken translation of the French rouet de rats, a "wheel of rats" (rat king in French is roi-de-rats). But this is an unlikely etymology. More likely, rat king harkens to the German Rattenkönig—an insult for the pope, but also a term used to describe elderly rats. (It was believed that senior rats would sit on the tails of younger rats to make their nests, and that, if the tails tangled, the elder rat would survive by having its meals delivered by the rodent world's proletariat. As the New York Tribune described in 1857, a rat king, “like so many kings, princes, and democratic officer holders, [depended] upon the labouring classes for support.”)

The rat king's existence is debatable; while there are several preserved specimens, they might be fakes perpetrated by hoaxers who wanted to make a quick buck. (Don't put it past our ancestors: “In medieval times, some sleazy European merchants glued bat wings to lizards and sold them as ‘dragons,’” notes Quail Bell magazine.) Owing to a lack of solid contemporary evidence, zoologists remain skeptical of rat kings—but open to the possibility that they are freak accidents.

Other rodents, after all, do get tied up in each other’s business. In 1951, a "squirrel king" appeared in a South Carolina zoo. In 2013, six more tangled squirrels were saved by veterinarians in Canada. And just this year in Maine, four baby squirrels were recorded on video with their tails linked like "a giant dreadlock," according to the man who discovered them.

If real, how do rat kings occur? Some theories are more crackpot than others: In the 17th and 18th centuries, naturalists suggested the tails had been woven during birth, glued by the afterbirth. Others suggested that healthy rats deliberately tangled the tails of weaker rodents to make a nest. Both theories are unlikely.

The most plausible explanation is that black rats—which have long, supple tails and reside in close quarters during winter—may come in contact with a sticky or frozen substance such as sebum (secreted from the critters’ skin), sap, food, feces, frozen urine, or frozen blood. The bonding agent may solidify as the animals slumber. Once the rodents realize their tails are glued, they might create a tighter knot as they attempt to wriggle free.

This explanation has a ring of truth: Most rat kings were discovered during the winter or a frosty shoulder season, and they’re usually found in a tight shelter.

Over the past five centuries, there have been 30 to 60 recorded rat king sightings. In 1973, the biologist and writer Maarten ‘t Hart tracked down all of them. Using Hart’s delightful book Rats as our primary guide, we now present a timeline of nearly every recorded rat king sighting since the 16th century.

(Note: We excluded approximately a dozen sightings that Hart argued were dubious, and we're certain that more instances exist. But, to be frank, after seeing the photographs below, you might understand why this timeline is the sort we’d prefer to never have to update.)

Rat King from Sabucus's EmblemataWellcome Images, Wikimedia Commons // CC BY 4.0

1576: Johannes Sambucus, a Hungarian historian, releases the fourth edition of his popular Emblemata—essentially a 16th century picture book—called Emblemata cum aliquot nummis antiqui operis. In it, Sambucus describes how servants in Antwerp, Belgium discovered seven rats with knotted tails. (The same volume contains stories involving unicorns, so take that for what it’s worth.)

July 1683: In Strasbourg, France, a man named Würtzen discovers in his cellar six “strikingly large rats with their tails so intertwined and fused that they could not be separated without injury,” a contemporary report states. The varmints are exhibited at the town hall, and an illustrated print of the braided bunch is published in the Mercure Galant.

1690: After hearing his floorboards squeak for all the wrong reasons, a bigwig in Kiel, Germany, orders boiling water poured down a rathole. Four rodents scamper out, but when the squealing continues, the homeowner decides to remove the floor tiles. He discovers 14 tangled rats, which are promptly dumped in a privy.

1694: In Krossen, Germany, 15 fused rats are found at a mill. They are killed with boiling water and strung from an oak tree, giving passersby a chance to gawk.

1705: A lump of snarled rats is discovered in Keula, Germany. It’s pickled in alcohol and later disappears.

The 1683 rat king, as illustrated by Wilhelm Schmuck Wikimedia Commons // Public Domain

July 1719: A rodent tumbleweed—population nine—appears in Roßla, Germany. (The naturalist Johann Heinrich Linck supposedly makes engravings of the monster.)

1722: Residents in the village of Dieskau, Germany, find another reason to avoid eating their vegetables when 12 tangled critters are found rooting through a barrel of peas. Euthanized by a cascade of boiling water, the rats are taken to Dresden’s Royal Natural History Collection. In 1849, this ratty rosette is presumed lost in a fire.

1722: A writhing cluster of rats (number unknown) grips Leipzig, Germany. The gnarled specimen is killed, pickled in a jar of alcohol, and paraded through the city. It’s later mummified in a private museum. Like any good mummy, it mysteriously goes missing.

1725: Eleven rats of various sizes—said to be a momma-rat and its young—are found entangled in Dorndorf, Germany.

1727: In a banner year for rat kings, naturalist Johann Linck reports that a whopping four rat kings are sighted in Germany. Hart, however, claims that only one of these is mildly credible: the rat king of the quaint mountainside town of Wernigerode, which is said to be preserved by a local count.

1748: German zoologist Johann Goeze reports that a gross ball of 18 rats has turned up in the town of Gross-Baullhausen, Germany.

An illustration from Henri Coupin's 1903 book Les Animaux ExcentriquesPublic Domain

1748: A lump of 10 plump male rats appears at a monastery in the spa town of Bad Langensalza, Germany. The sanctity of life apparently does not extend to rat kings: It’s killed, dunked in alcohol, and, like the other specimens, later goes M.I.A.

1759: A tinsmith in Arnstadt, Germany, is startled to find a buffet of six snagged vermin near the town market. The discovery becomes the subject of five oil paintings, four of which were lost during World War II. (According to Hart, the only surviving artwork is hung in Arnstadt’s Castle Museum.)

1772: Twelve twist-tied rats are discovered in Erfurt, Germany; the specimen is later illustrated by J. J. Bellerman in his 1820 book Ueber das Bisher Bezweifelte Dasein des Rattenkönigs, or On the Hitherto Doubted Existence of Rat Kings. (For those curious, the book does not sell very well.)

December 1774: Christian Kaiser, a miller’s assistant, finds 16 snarled rats in Lindenau, Germany, and drags them to an artist named Johan Adam Fassauer, requesting a painting. Instead, Fassauer begins exhibiting the rats to the public for a fee. When Kaiser realizes that the painter is profiting off his discovery, he demands for the specimen’s return. (According to Hart, “the end of the story is unknown,” but other reports suggest the dispute led to one of the strangest custody battles a courtroom has ever witnessed.)

1793: A Gordian knot of 10 rats appears in a stable in Wundersleben, Germany.

1793: In Brunswick, Germany, seven entangled rodents make a surprise visit to a local privy.

1810: Brunswick celebrates back-to-back rats! After days of interminable squeaking, a well-to-do citizen tears up his floorboards only to find a tangled jumble of seven rodents. “All of their tails had been joined together so firmly and so inextricably that they could not be pulled apart,” writes Hart.

December 1822: A thresher in Döllstädt finds two gobs of rats—one consisting of 28 rodents, the other 14—inside the main beam of a barn. “All 42 seemed to be very hungry, and squeaked continuously but looked perfectly healthy,” reported zoologist Alfred Brehm. “All were of equal and moreover of such considerable size that they must have been born during the last spring.” The rats are paraded through town before being thrown unceremoniously onto a dungheap.

The 1828 rat king from Thuringia, which contains 32 rodents, is the largest specimen in the world.Naturkundliches Museum Mauritianum Altenburg, Wikimedia Commons // CC BY-SA 3.0

May 1828: Doing spring cleaning, Miller Steinbruck of Thuringia, Germany, finds a scorched clump of 32 rodents in his chimney. The terrifying rat king is today held at the Mauritianum Museum in Altenburg, Germany.

May 1829: An artist gets creative with a coil of eight rats discovered in Flein, Germany. “The individuals constituting this king were not arranged in the usual circle but looked like a bunch of flowers with the tails representing the knotted stems,” Hart writes. Today it’s preserved at the Stuttgart Natural History Museum.

1837: A dirty dozen appears in Zaisenhausen, Germany, prompting the discoverer to call upon a pastor. The holy man gives the sample to a local museum director, but when the director dies, he brings any knowledge of the rat king's whereabouts to his grave.

1841: Half a dozen knotted rats appear in Bonn, Germany. They are preserved for more than a century at the University Zoological Institute, but it becomes one of many museum casualties during World War II.

March 1844: A smorgasbord of seven rats surfaces in the small Bavarian town of Leutershuasen, Germany.

1870: In Keula, Germany, a rat king of unknown number is discovered and preserved, but it, too, disappears during World War II.

February 1880: After hearing unusual squeaks from high up a wall, a postman in Düsseldorf, Germany uncovers a skein of eight rats, which is photographed and preserved, but (you guessed it!) is lost during World War II.

Illustration of a rat king from volume 6 of The Picture Magazine, 1895.Public Domain

1883: In an attempt to determine if rat kings are a hoax, German zoologist Hermann Landois ties the tails of 10 dead brown rats together. According to Hart, the results must have been disappointing. “Anyone who ties up the tails of dead rats (I have tried it several times) will obtain something that in no way resembles the kings found in nature: the knots are too neat.” But Hart does not discount that there may be frauds out there: “[It was] lucrative to own a king, and so people began tying tails together. Kusthardt (1915) reports that many such sham kings were exhibited at fairs and similar gatherings.”

April 1883: After loud squeals emerge from underneath a merchant’s toilet in Lüneburg, Germany, a motley knot of eight rats is discovered. Like many others, it is purportedly preserved but lost during the Second World War.

1889: A young rat king numbering five or six turns up in Obermodern-Zutzendorf, Germany. Reports of the discovery make it to England, where the The Newcastle Weekly Courant spreads the myth that, like royalty, the rats were sustained by the charitable contributions of lowlier rodents: “The rats were in the very best conditions—conclusive that astonishingly good care had been bestowed upon them by their more fortunate rat brethren.”

The 1894 Strasbourg rat kingMusées of Strasbourg, M. Bertola

April 1894: A frozen ratcicle containing 10 rodents—many of which are pocked with teeth marks and gnawed legs—is found under a hay-bale in Dellfeld, Germany. You can visit the specimen at the Strasbourg Zoological Museum.

November 1899: A ratpack of seven crosses the border and visits Courtalain, France. It’s currently kept at the Musee de Chateaudun, a two-hour train ride from Paris.

May 1905: Seven young rodents are reported in Hamburg, Germany, now preserved in the city’s Natural History Museum. (The next year, a lucky seven strikes again in le Vernet, France.)

January 1907: A potpourri of 10 black rats appears in Rudersdorf. It is preserved.

October 1914: An adolescent rat king is discovered (alive) in Moers, Germany. It is preserved (not so alive) and later disappears.

The 1899 Courtalain rat king, now preserved in the Musee de Chateaudun.Selbymay, Wikimedia Commons // CC BY-SA 3.0

March 1918: The rat king takes a vacation to Bogor, Java! Not only is this weave of 10 rats one of the few reported outside of Central Europe, it’s the only report not to involve black rats.

1930s: In New Zealand, a cluster of eight contorted rats drops from the rafters of a shipping office. Clerks beat it generously with a pitchfork and then, also generously, donate it to the Otago Museum, where it now resides. (The tails, the museum discovered, were tangled with horsehair.)

October 1937: Hark! A farmer’s servant discovers nine gnarled rats in a starling’s nest in Büngern, Germany.

1940: In what’s believed to be the Lictenplatte district of Offenbach, Germany, a king of five young rats is found squirming in a pigsty.

June 1949: In Berlin, Germany, three separate rats are tossed into a bucket on the evening of June 2. The next morning, the three rats have mysteriously tangled into a knot. Herr Otto Janack, an official with the local rodent extermination department, disentangles the rodents and comes away thinking that it’s all a bad joke—or one of nature’s weird, twisted miracles.

1951: A rat king of four adults is discovered in Châlons-sur-Marne, France (now renamed Châlons-en-Champagne).

The Limburg rat king of 1955, now displayed at the Museum of Maastricht.Vassil, Wikimedia Commons // CC0 1.0

1955: The Natural History Museum of Maastricht picks up a crowd-pleasing specimen: a seven-strong rat king found in Limburg, Netherlands.

1961: According to a Russian-language journal article about hollow-dwelling birds, a rat king of unknown size appears in Lithuania.

February 1963: A Dutch farmer in Rucphen, Netherlands, hears a loud squeal and follows the noise to a pile of bean sticks in his barn. When he notices a rat, he kills it and attempts to pull it from the pile. It refuses to budge—until the farmer realizes that six more rodents are connected to the original rat. These, too, are exterminated and the specimen is later X-rayed.

1966: A man by the name of Wierts attempts to make his own rat king by gluing the tails of six live albino lab rats. When the animals attempted to wriggle free, their tails became entangled in a knot. Wierts then anesthetized the rats and removed the glue to see if they remained knotted like a pretzel ... and they did.

The Vendée rat king of 1986, now held at the Natural History of Museum in Nantes, France.© Patrick JEAN / Muséum de Nantes, France

1986: A roi-de-rats of nine turns up in Vendée, France. Today you can see it in the Natural History Museum in Nantes.

2005: In Saru, Estonia, a farmer discovers a cluster of 16 rats—nine of which are alive—in a shed, their tails tangled by frozen sand. It is taken to the Natural History Museum at the University of Tartu, where it is preserved in alcohol. (It’s reported that two other rat kings were discovered in Estonia in the 20th century, one of which contained 18 live rats [PDF]!)

The Saru, Estonia rat king of 2005 at the Natural History Museum at the University of Tartu.Permission of Andrei Miljutin

Amazon's Best Black Friday Deals: Tech, Video Games, Kitchen Appliances, Clothing, and More

Amazon
Amazon

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Black Friday is finally here, and Amazon is offering great deals on kitchen appliances, tech, video games, and plenty more. We will keep updating this page as sales come in, but for now, here are the best Amazon Black Friday sales to check out.

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Instant Pot/Amazon

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Sony

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Apple/Amazon

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9 Things Invented By Accident

These sugary summer treats were an accidental invention.
These sugary summer treats were an accidental invention.
Daniel Öberg, Unsplash

Not every great invention was created according to plan. Some, in fact, were the result of a happy accident. In November 2020, the pharmaceutical company AstraZeneca announced that the COVID-19 vaccine it had developed in partnership with Oxford University was 90 percent effective when administered in a dosing regimen they had discovered thanks to some “serendipity.” This wasn't the only unintentional discovery in history, of course. From penicillin to artificial sweeteners, all nine of the everyday items below were invented entirely by accident.

1. Penicillin

On September 28, 1928, Scottish scientist Alexander Fleming discovered that a petri dish of staphylococcus bacteria that had been inadvertently left out on the windowsill of his London laboratory had become contaminated by a greenish-colored mold—and encircling the mold was a halo of inhibited bacterial growth. After taking a sample and developing a culture, Fleming discovered that the mold was a member of the Penicillium genus, and the rest, as they say, is history.

2. Corn Flakes

The two Kellogg brothers—Dr. John Harvey Kellogg and his younger brother (and former broom salesman) Will Keith Kellogg—worked at Battle Creek Sanitarium in Michigan, where John was physician-in-chief. Both were strict Seventh-day Adventists, who used their work at the sanitarium to promote the austere dietary and moralist principles of their religion (including strict vegetarianism and a lifelong restraint from excessive sex and alcohol) and to carry out research into nutrition, and the impact of diet on their patients. It was during one of these experiments in 1894 that, while in the process of making dough from boiled wheat, one of the Kelloggs left the mash to dry for too long and when it came time to be rolled out, it splintered into dozens of individual flakes. Curious as to what these flakes tasted like, he baked them in the oven—and in the process, produced a cereal called Granose. Some later tinkering switched out the wheat for corn, and gave us corn flakes.

3. Teflon

Polytetrafluoroethylene—better known as PTFE, or Teflon—was invented by accident at a DuPont laboratory in New Jersey in 1938. Roy Plunkett, an Ohio-born chemist, was attempting to make a new CFC refrigerant when he noticed that a canister of tetrafluoroethylene, despite appearing to be empty, weighed as much as if it were full. Cutting the canister open with a saw, Plunkett found that the gas had reacted with the iron in the canister’s shell and had coated its insides with polymerized polytetrafluoroethylene—a waxy, water-repellent, non-stick substance. Du Pont soon saw the potential of Plunkett’s discovery and began mass producing PTFE, but it wasn’t until 1954, when the wife of French engineer Marc Grégoire asked her husband to use the same substance to coat her cookware to stop food sticking to her pans, that the true usefulness of Plunkett’s discovery was finally realized.

4. Slinky

In 1943, naval engineer Richard T. James was working at a shipyard in Philadelphia when he accidentally knocked a spring (that he had been trying to modify into a stabilizer for sensitive maritime equipment) from a high shelf. To his surprise, the spring neatly uncoiled itself and stepped its way down from the shelf and onto a pile of books, and from there onto a tabletop, and then onto the floor. After two years of development, the first batch of 400 “Slinky” toys sold out in just 90 minutes when they were demonstrated in the toy department of a local Gimbels store in 1945.

5. Silly Putty

At the height of World War II, rubber was rationed across the United States after Japan invaded a number of rubber-producing countries across southeast Asia and hampered production. The race was on to find a suitable replacement—a synthetic rubber that could be produced inside the U.S. without the need of overseas imports, which eventually led to the entirely unexpected invention of Silly Putty. There are at least two rival claims to the invention of Silly Putty (chiefly from chemist Earl L. Warrick and Scottish-born engineer James Wright), both of whom found that mixing boric acid with silicone oil produced a stretchy, bouncy rubber-like substance that also had the unusual ability of leaching newspaper print from a page (an ability that changing technology has now eliminated).

6. Post-It Notes

Pexels, Pixabay

In 1968, a 3M chemist named Dr. Spencer Silver was attempting to create a super-strong adhesive when instead he accidentally invented a super-weak adhesive, which could be used to only temporarily stick things together. The seemingly limited application of Silver’s product meant that it sat unused at 3M (then technically known as Minnesota Mining & Manufacturing) for another five years, until, in 1973, a colleague named Art Fry attended one of Silver’s seminars and struck upon the idea that his impermanent glue could be used to stick bookmarks into the pages of his hymnbook. It took another few years for 3M to be convinced both of Fry and Silver’s idea and of the salability of their product, but eventually they came up with a unique design that worked perfectly: a thin film of Spencer’s adhesive was applied along just one edge of a piece of paper. After a failed test-market push in 1977 as Press ’N Peel, the product went national as the Post-It note in 1980.

7. Saccharin

In 1878 or '79 (sources differ), Constantin Fahlberg, a chemist studying the properties of oxidized coal tar at Johns Hopkins University in Baltimore, Maryland, discoveredwhile eating his meal one evening that food he picked up with this fingers tasted sweeter than normal. He traced the sweetening effect back to the chemical he had been working with that day (Ortho-sulfobenzoic Acid Imide, no less) and, noting its potential salability, quickly set up a business mass producing his sweetener under the name Saccharin. Although quickly popular (and equally quickly controversial), it would take the sugar shortages of two World Wars to make the discovery truly universal.

8. Popsicles

The first popsicle was reportedly invented by 11-year-old Frank Epperson in 1905, when he accidentally left a container of powdered soda and water, with its mixing stick still inside, on his porch overnight. One unexpectedly cold night later, and the popsicle—which Epperson originally marketed 20 years later as an Epsicle—was born.

9. Safety glass

Safety glass—or rather, laminated glass—was accidentally discovered by the French chemist Édouard Bénédictus when he knocked a glass beaker from a high shelf in his laboratory and found, to his surprise, that it shattered but did not break. His assistant informed him that the beaker had contained cellulose nitrate, a type of clear natural plastic, that had left a film on the inside of the glass. He filed a patent for his discovery in 1909, and it has been in production (albeit in various different forms) ever since.