The Poison-Detecting Secret Weapon of the Middle Ages: Unicorn Horn

A woodcut of a unicorn from 1551
A woodcut of a unicorn from 1551

In the Middle Ages and into the Renaissance, Europeans knew that unicorns were real. After all, their horns were the treasured possessions of royalty, nobility, and even clergy. Charles VI of France had one, as did Lorenzo de Medici, and Danish rulers sat on a throne carved out of them. Queen Elizabeth I had a fully intact horn she used as a scepter; it was valued at 10,000 pounds—roughly the cost of a castle in her day. In fact, unicorn horns were considered so valuable the Elizabethan dramatist John Dekker wrote that one was "worth a city."

But unicorns horns weren't prized just for their beauty or rarity, or as tokens of extreme wealth. They were believed to be powerful defense against disease—and poison.

Fierce But Pure

Chastity, oil painting by a follower of Timoteo Viti
Wellcome Images // CC BY 4.0

For an animal that never existed, the unicorn got around. The ancient myths of India and China mention unicorn-like animals, as did the tales Greek travelers brought back from India and other far-flung lands. The earliest Greek description is from the historian Ctesias, who wrote around 400 BCE of a large, agile animal with a white body, dark red head, and a long horn on its forehead. About a hundred years later, scholars translating the Old Testament interpreted a horned animal known in Hebrew as re'em as a unicorn (though modern translators prefer the term auroch, an extinct species of cattle). Writing in the first century CE, Pliny the Elder described the unicorn is "the fiercest animal, and it is said that it is impossible to capture one alive. It has the body of a horse, the head of a stag, the feet of an elephant, the tail of a boar, and a single black horn three feet long in the middle of its forehead.”

From the beginning, accounts of the unicorn emphasized their healing and purifying properties. Ctesias wrote, "Those who drink out of these horns, made into drinking vessels, are not subject, they say, to convulsions or to the holy disease [epilepsy]. Indeed, they are immune even to poisons if, either before or after swallowing such, they drink wine, water, or anything else from these beakers." Similar accounts appeared for centuries: Around the 3rd century CE, the Greek intellectual Philostratus wrote that "the Indians make drinking-cups from this horn, which have such virtue that the man who drinks from one will for one whole day neither fall ill, nor feel pain if wounded, nor be burned by passing through fire, nor even be affected by poisons which he could not swallow at any other time without harm."

By the 12th century, a German nun known for her saintly visions, Hildegard of Bingen, recommended a paste of powdered unicorn liver and egg yolk as a cure for leprosy, although she conveniently noted that it could fail if the "leper in question happens to be one whom death is determined to have or else one whom God does not wish to be cured." Unicorn hide was also recommended in boots and belts, partly as prevention for that greatest scourge of the Middle Ages: plague.

Belief in the healing powers of the unicorn focused especially on its mysterious, twisting horn. The substance, often called alicorn, was associated with great purity as well as healing, sometimes with religious overtones (the purity of the white animal was thought to be connected to Jesus Christ, and the horn to his cross). Hunters in search of a unicorn were supposed to lure the animal with a female virgin, capturing the animal once it fell asleep in her lap.

A Common Deception

A narwhal tuskWellcome Images // CC BY 4.0

Of course, no such hunters were ever successful. Objects portrayed as being made from unicorn sometimes came from rhinoceroses or mammoth fossils but most often in Europe from narwhals, which were hunted by the Vikings in the North Atlantic. The Vikings harvested the narwhals’ spiraling tusks and sold them on to traders who either didn't know, or didn't care, about their true origins in the sea.

Once obtained, alicorn could be taken in many forms. Powdered, it was applied to dog bites and other wounds or consumed as treatment for plague, gout, and other diseases. The influential German physician Johann Schröder recommended it for childhood epilepsy. And although other physicians numbered among the earliest skeptics, apothecaries used unicorns widely in their potions. Eau de licorn—water purified by the introduction of unicorn’s horn or by being poured through a hollowed-out segment of horn—was also widely sold and reputed to have health benefits.

While the extraordinary cost of the intact horns made them showpieces for the rich, powdered unicorn horn was an affordable remedy for the average citizen. This was largely because other substances could be easily substituted: horse hoofs, fossils, and other types of horn. In fact, the widespread problem of fraud led to frequent tests of the authenticity of the horn itself, including presenting it to spiders and scorpions and observing to see if they avoided it or died. If they did, the item was thought to be genuine horn.

Poison-Proof

A page from a 17th-century French medical text discussing unicornsWellcome Images // CC BY 4.0

Poisoning was particularly feared during the Middle Ages and into the Renaissance by the back-stabbing royalty and nobility keen to maintain their positions, not to mention their lives. Such an insidious crime required extraordinary measures: While European royalty kept other poison-detectors, including rubies, bezoar stones, and griffin claws, unicorn horn was a favored material for protection as well.

Whole unicorn horns were deployed on dining tables as poison detectors, while fragments of horn, called touches by the French, could be touched or dipped to plates of food to detect the presence of toxins. They could also be hung on chains or mounts of precious metal (actually less valuable materials, pound for pound, than the horn itself). French royalty had utensils made with alicorn, while other members of the European nobility had the horn inset into jewelry. The horn was expected to provide an alert to the presence of poison by changing color, sweating beads of moisture, or actually steaming. Alicorn might also be dipped into water or run over the actual linens and wall hangings in a banquet hall. Goblets fashioned from unicorn horn were also made across the continent; some believed these would shatter upon contact with a contaminated beverage.

While some medical writers, such as the famed French surgeon Ambroise Paré, were skeptical of the powers of the unicorn horn, many others believed in its merits. The Italian scholar and naturalist Andrea Bacci wrote a defense of the horn's use in 1573, telling the story of a man who consumed a poisoned cherry but was saved thanks to unicorn horn dissolved in wine. He also described an experiment in which two pigeons were fed arsenic, but the one who was given some scrapings of unicorn horn recovered and lived. The other died two hours after being fed the toxin [PDF].

But by the 17th century, the myth of the unicorn had begun to tarnish. European travelers to the Arctic brought back tales of the living narwhal, and further missions to other continents disproved the existence of unicorns by process of elimination, since no such animal was ever sighted. In July 1661, the men of the newly formed Royal Society put unicorn horn to the test: They placed a spider in a circle of powdered unicorn’s horn to see what would happen. From from being repelled by the horn, as writers had long claimed, the spider immediately scurried across the powder to escape. The men repeated the experiment several times, each with the same results. Their trial helped sound the death knell for credulous belief in the magical properties of unicorn horn.

The loss of value resulted in the disappearance or destruction of many precious specimens. Items once said to be made from unicorn horn are still in some museum collections, and very occasionally turn up for sale—still bearing their historical value, though no longer imbued with the mysterious properties that once made them worth a city or a castle.

10 Rad Gifts for Hikers

Greg Rosenke/Unsplash
Greg Rosenke/Unsplash

The popularity of bird-watching, camping, and hiking has skyrocketed this year. Whether your gift recipients are weekend warriors or seasoned dirtbags, they'll appreciate these tools and gear for getting most out of their hiking experience.

1. Stanley Nesting Two-Cup Cookset; $14

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Stanley’s compact and lightweight cookset includes a 20-ounce stainless steel pot with a locking handle, a vented lid, and two insulated 10-ounce tumblers. It’s the perfect size for brewing hot coffee, rehydrating soup, or boiling water while out on the trail with a buddy. And as some hardcore backpackers note in their Amazon reviews, your favorite hiker can take the tumblers out and stuff the pot with a camp stove, matches, and other necessities to make good use of space in their pack.

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2. Osprey Sirrus and Stratos 24-Liter Hiking Packs; $140

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Osprey’s packs are designed with trail-tested details to maximize comfort and ease of use. The Sirrus pack (pictured) is sized for women, while the Stratos fits men’s proportions. Both include an internal sleeve for a hydration reservoir, exterior mesh and hipbelt pockets, an attachment for carrying trekking poles, and a built-in rain cover.

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3. Yeti Rambler 18-Ounce Bottle; $48

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Nothing beats ice-cold water after a summer hike or a sip of hot tea during a winter walk. The Yeti Rambler can serve up both: Beverages can stay hot or cold for hours thanks to its insulated construction, and its steel body (in a variety of colors) is basically indestructible. It will add weight to your hiker's pack, though—for a lighter-weight, non-insulated option, the tried-and-true Camelbak Chute water bottle is incredibly sturdy and leakproof.

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4. Mappinners Greatest 100 Hikes of the National Parks Scratch-Off Poster; $30

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The perfect gift for park baggers in your life (or yourself), this 16-inch-by-20-inch poster features epic hikes like Angel’s Landing in Zion National Park and Half Dome in Yosemite National Park. Once the hike is complete, you can scratch off the gold foil to reveal an illustration of the park.

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5. National Geographic Adventure Edition Road Atlas; $19

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Hikers can use this brand-new, updated road atlas to plan their next adventure. In addition to comprehensive maps of all 50 states, Puerto Rico, Canada, and Mexico, they'll get National Geographic’s top 100 outdoor destinations, useful details about the most popular national parks, and points on the maps noting off-the-beaten-path places to explore.  

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6. Adventure Medical Kits Hiker First-Aid Kit; $25

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This handy 67-piece kit is stuffed with all the things you hope your hiker will never need in the wilderness. Not only does it contain supplies for pain, cuts and scrapes, burns, and blisters (every hiker’s nemesis!), the items are organized clearly in the bag to make it easy to find tweezers or an alcohol wipe in an emergency.

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7. Hiker Hunger Ultralight Trekking Poles; $70

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Trekking poles will help increase your hiker's balance and stability and reduce strain on their lower body by distributing it to their arms and shoulders. This pair is made of carbon fiber, a super-strong and lightweight material. From the sweat-absorbing cork handles to the selection of pole tips for different terrain, these poles answer every need on the trail. 

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8. Leatherman Signal Camping Multitool; $120

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What can’t this multitool do? This gadget contains 19 hiking-friendly tools in a 4.5-inch package, including pliers, screwdrivers, bottle opener, saw, knife, hammer, wire cutter, and even an emergency whistle.

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9. RAVPower Power Bank; $24

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Don’t let your hiker get caught off the grid with a dead phone. They can charge RAVPower’s compact power bank before they head out on the trail, and then use it to quickly juice up a phone or tablet when the batteries get low. Its 3-inch-by-5-inch profile won’t take up much room in a pack or purse.

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10. Pack of Four Indestructible Field Books; $14

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Neither rain, nor snow, nor hail will be a match for these waterproof, tearproof 3.5-inch-by-5.5-inch notebooks. Your hiker can stick one in their pocket along with a regular pen or pencil to record details of their hike or brainstorm their next viral Tweet.

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10 Facts About Famed Paranormal Investigators Ed and Lorraine Warren  

Ed Warren and Lorraine Warren in Amityville II: The Possession (1982).
Ed Warren and Lorraine Warren in Amityville II: The Possession (1982).
Warner Bros. Home Entertainment

When it comes to investigations of the paranormal kind, no two ghost hunters loom larger than Ed and Lorraine Warren. Over the course of 50 years, Ed, a demonologist, and Lorraine, a trance medium, looked into thousands of cases around the globe, and claimed to have encountered phenomena so scary that their exploits were often turned into films, including The Amityville Horror, The Conjuring movies, and The Haunting In Connecticut. But even if you're familiar with their most famous cases, there's probably still a lot you don't know about the Warrens.

1. Ed Warren grew up in a haunted house.

Ed Warren826 Paranormal via Flickr // CC BY 2.0

When Ed was 5, he claimed he saw an apparition: a dot of light that grew until it became his family's landlady, who had died the year before. In The Demonologist: The Extraordinary Career of Ed and Lorraine Warren, Ed recalled that she was "semi-transparent, wearing what looked like some sort of shroud ... then she vanished." Soon after, Ed was having dreams of dead relatives he’d never met, including an aunt who would send him messages about his future, telling him that he would help many priests but never become a priest himself. "I'm not a priest today, but I do work closely with them," he said in The Demonologist.

2. Lorraine Warren discovered her abilities when she was a child.

Like Ed, Lorraine began having unusual experiences when she was young, too—but she just assumed everyone had those same abilities. That all changed when she was 12. As she recalled in The Demonologist, it was Arbor Day at her all-girls' private school, and her classmates had just planted a sapling. "Just as soon as they put the sapling in the ground, I saw it as a fully grown tree ... filled with leaves blowing in the wind," she said. When a nun asked her why she was staring at the sky, Lorraine responded, "I told her I was just looking up into the tree ... 'Are you seeing the future?' she asked me, just as sternly. 'Yes,' I admitted, 'I guess I am.'"

3. Ed and Lorraine Warren began dating as teenagers.

Ed and Lorraine both lived in Connecticut and met in 1944, when they were both just 16 years old—Ed worked as an usher at a movie theater that Lorraine and her mother frequented. They began dating, and soon after, Ed went off to fight World War II.

4. Ed and Lorraine Warren got married in 1945, thanks to a sunken ship.

In 1945, when Ed was 17 years old, he enlisted in the Navy. He had only been deployed for a total of four months when he was sent back home on a 30-day "Survivor's Leave" after his ship went down in the North Atlantic Sea. It was during that short break that Ed and Lorraine got married, then he returned to war. The couple later had a daughter named Judy.

5. The Warrens thought they'd make their livings as artists.

The Conjuring (2013).Warner Bros.

After the war, the Warrens had to figure out how to make a living. "Each of us had skills as landscape artists, and we each harbored a desire to paint," Lorraine said. Ed had taken art classes, so, she said, "we began our marriage under the assumption that we were going to be artists."

Rather than painting landscapes, the Warrens decided on a more unusual subject on which to focus: haunted houses, which Ed found in the newspaper. They'd go to the houses, sketch them, then knock on the door and "offer [the sketch] for information about the haunting," Lorraine said. If the story was compelling enough, they'd actually paint the house and sell that artwork later. They spent about five years going around the United States, painting and investigating haunted houses.

6. Lorraine Warren was initially a skeptic.

Despite her early experiences with clairvoyance, Lorraine didn’t believe in ghosts until later in life, after she and Ed began visiting and painting haunted houses. "In the beginning, I was more than a bit wary of the people with whom we spoke," she said in The Demonologist. "I thought they were kind of suffering from overactive imaginations or were just making things up to get attention." But when she noticed the similarities between the experiences—including from people who had never met, and who were from opposite sides of the country—she became a believer.

7. Ed and Lorraine Warren founded the New England Society for Psychic Research in 1952.

The Warrens founded the New England Society for Psychic Research to document their cases, and they also created The Occult Museum—a space in their Monroe, Connecticut, home, which adjoined Ed's office—to house haunted objects and the files and tapes from their investigations. Today, the NESPR is run by the Warrens's daughter Judy and son-in-law, Tony Spera, and its website keeps a log of some of the cases the Warrens investigated, including that of an alleged werewolf and the infamous possessed doll, Annabelle.

8. Lorraine Warren had her abilities tested.

Lorraine WarrenJason Kempin, Getty Images

As the Warrens began taking on bigger and bigger cases, skepticism about the couple grew. To quiet critics, Lorraine agreed to be tested by Dr. Thelma Moss, an actress-turned-psychologist and parapsychologist (a researcher with an interest in the occult) working in a UCLA lab studying things like Kirlian photography. She found that Lorraine's clairvoyance was “far above average,” according to The Demonologist.

9. Ed and Lorraine Warren never charged money for their investigations.

Instead, they made a living from giving lectures at colleges, and by licensing the rights to their stories for film, TV, and book projects.

10. Ed and Lorraine Warren saw their main roles as educators.

The Warrens began giving lectures because, according to The Demonologist, there was a growing interest in the occult in the late 1960s, and many of the people they saw affected by dark phenomena were college students. They hoped that, through their lectures, they might discourage people from exploring the occult in the first place.