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11 Lesser-Known Inventions by Famous Inventors

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Getty / iStock

With their visionary thinking and innovative approach to solving problems, inventors have the power to save lives, increase productivity, and change the course of history. But most inventors don't achieve success with every creation they devise. For every telephone, Miracle Mop, or automobile, there’s an induction balance device or a car made out of soybeans. Take a look at these 11 lesser-known inventions by famous inventors.


Sometime around 1500, Leonardo da Vinci invented an unusual solution to a military problem. The Ottoman Empire’s naval attacks of Venice were decimating the republic, so Leonardo designed a special scuba suit that would allow members of the Venetian navy to swim underwater and sneak attack the Ottoman Empire’s ships. Made of leather, the "scuba" suit (although technically more like a diving suit) had a mask, goggles, and even a pouch to pee in. Two tubes connected to the suit allowed the diver to breathe air from above the water’s surface or from a small container of air. The Venetian navy opted against adopting the suit (seen here in all its scary-looking glory), and modern scuba diving didn’t become possible until the mid-20th century.


French musician and glass armonica expert Thomas Bloch shows his instrument to journalists prior to a rehearsal at the Los Angeles Music Center in 2014. JOE KLAMAR/AFP/Getty Images

Benjamin Franklin most famously invented bifocals, but he also dreamed up an unusual musical instrument. In 1761, while in London, Franklin heard strange sounds created as a member of the Royal Society rubbed his wet fingers around the rims of wine glasses. Inspired to make his own instrument, Franklin arranged 37 glass bowls horizontally on a rod and connected the rod to a wheel and foot pedal. Pressing the foot pedal made the bowls spin, and touching the bowls with wet fingers produced vibrations of sound. In 1762, a musician named Marianne Davies learned to play the glass armonica and went on tour, exposing audiences across Europe to its ethereal sounds. The glass armonica became so popular that Beethoven and Mozart wrote compositions for the instrument, and over 5000 glass armonicas were built. But because Franklin’s instrument was relatively quiet, it lost popularity in the 1800s as louder, amplified instruments became the norm (and the instrument itself developed a still-debated reputation for causing insanity).


Beloved by TSA agents and treasure hunters alike, metal detectors play a vital role in keeping people safe and locating hidden items. While most people remember him for inventing the telephone, Alexander Graham Bell also created the first practical metal detector (probably inspired by the earlier work of Gustave Trouvé). In early July 1881, President James Garfield was slowly dying after being shot twice by Charles Guiteau. Doctors couldn’t find the bullet in Garfield’s body, so Bell got to work on a device that could find the bullet and save the president’s life. Bell called his machine—which consisted of a battery, condenser, handle, and telephone receiver to listen for clicking—an induction balance device. As Garfield became sicker, his doctor agreed to let Bell try the device on the president in late July and again in early August. Unfortunately, Bell couldn’t find the bullet—perhaps he didn’t assemble the machine properly, the bullet was buried too deep to be detected, or the president's metal mattress coils interfered with the device—and Garfield died on September 19, 1881.


Most people remember actress Hedy Lamarr for her beauty and brains. She co-invented a device that manipulated radio frequencies, making it harder for wartime enemies to jam radio-controlled torpedoes. Although she patented the device in August of 1942, hoping that the U.S. would use it to fight the Nazis, it was never used. Decades later, people realized that modern wireless technology relied on the ideas in her patent. But besides inventing an antecedent to Wi-Fi, GPS, and Bluetooth, Lamarr also invented an effervescent tablet that transformed flat water into a carbonated drink. Although the tablet worked—dissolving the tablet in the water did create fizz—the product didn’t taste good and was too similar to Alka-Seltzer. Not every invention can pave the way for Wi-Fi.


After Thomas Edison invented the phonograph, he tackled his next big project: the talking doll. Patented in 1890, Edison’s talking dolls were almost 2 feet tall, had wooden limbs, and contained mini phonographs stuffed inside the children’s toys. Although not the first talking doll, Edison realized that by using the phonograph he could produce far more complicated words and phrases than the competition. Because of the technological limitations of the time, each sound recording was one-of-a-kind and featured women speaking the words to lullabies and nursery rhymes such as "Twinkle, Twinkle, Little Star" and "Jack and Jill." To Edison’s disappointment, kids and their parents didn’t like the dolls because they were expensive, fragile, creepy, and had poor sound quality. The talking doll turned out to be one of Edison’s many failures—or, as he would phrase it, just another one of his 10,000 things that didn’t work.



In the 1920s, entrepreneur Clarence Birdseye invented a method of flash freezing, packaging, and distributing seafood and other products. Although he’s known as the father of the frozen foods industry (his company Birds Eye still sells frozen veggies today), Birdseye also invented a mechanical harpoon gun to tag whales. Interested in learning more about fish and marine mammals, he built and patented a contraption to mark whales. Made of aluminum and rubber, the handheld harpoon didn’t recoil after shooting, providing a more pleasant tagging experience. Although Birdseye used his harpoon to tag dozens of finback whales, his invention was more for personal enjoyment than commercial use—or at least that's the official story. Some have accused Birdseye of using his device for whaling.


As an 11-year-old, Franklin loved swimming and wanted to swim faster. To increase his aquatic speed, he decided to wear a pair of wooden paddles around his wrists. Using round planks of wood, Franklin drilled holes to fit his thumbs through and grip the planks. Although the paddles helped him swim faster, the extra weight made his wrists tired. Franklin obviously moved on to bigger and better things, but his lifelong support of swimming as a healthy activity earned him an honorary spot in the International Swimming Hall of Fame.



Best known for inventing the Miracle Mop (Jennifer Lawrence portrayed her in the 2015 movie Joy), Joy Mangano also invented a type of elevated shoe. Called Performance Platforms, the sneakers have a rubber platform heel with Get Fit (TM) technology that can tone a wearer's hamstrings, quadriceps, and calves. Launched in 2010, the platform shoes claim to help users multitask by firming their muscles while they go about their daily business. Not bad for a sneaker.


Although most famous for producing a better light bulb, Edison also invented an early form of vacuum-sealed packaging. But rather than focus on preserving meat, Edison and the inventors he worked with concentrated on fruit. In October 1881, he patented his method to preserve fruit, which involved putting a fruit or vegetable into a glass vessel, pumping the air out, and sealing the vessel with heat. To read Edison’s own words about the science behind the process (and check out his elaborate diagram of the contraption), take a look at his patent [PDF].


George Washington Carver and Henry Ford. via Flickr // CC BY-NC-ND 2.0

In 1934, the inventors George Washington Carver and Henry Ford became pen pals, exchanging information and sharing their knowledge about agriculture and automobiles, respectively. Hoping to discover an alternative source of fuel to replace gasoline, Ford investigated the properties of peanuts and other crops with which Carver worked. In 1937, Carver visited Ford in Michigan so the two inventors could experiment with crops together. Ford's interest in chemurgy (making industrial products from agricultural products) culminated in a soybean car, a lightweight automobile made with plastic derived from a soybean mixture (and possibly other plants like hemp, flax and wheat—the formula was lost). In 1941, Ford debuted the soybean car at a summer festival in Michigan, but the vehicle never caught on.


Leonardo’s artistic skills came in handy when he sketched intricate diagrams of his ideas for inventions, which ranged from a more accurate clock to a flying machine. But he also sketched an invention for a self-propelled cart and a suit of armor that could sit down and wave its arms. Although Leonardo may have never built his robotic knight suit, his drawings of it indicate that a system of gears, wheels, and cables would allow the coat of arms to open its mouth, wave its arms, sit down, and stand up on its own. Scholars speculate that he devised the robotic knight as a way for monarchs to entertain and impress guests in their royal courts.

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When Lexicographer Samuel Johnson Became a Ghostbuster
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Dr. Samuel Johnson is today best known for his Dictionary of the English Language (1755), which remained the foremost authority on the English language until the Oxford English Dictionary appeared more than a century later. The dictionary took Johnson nine years to complete, for which he was paid the princely sum of 1500 guineas—equivalent to $300,000 (or £210,000) today. Although it wasn’t quite the commercial success its publishers hoped it would be, it allowed Johnson the freedom to explore his own interests and endeavors: He spent several years editing and annotating his own editions of all of Shakespeare’s plays, and traveled extensively around Britain with his friend (and eventual biographer) James Boswell—and, in 1762, helped to investigate a haunted house.

Johnson—who was born on this day in 1709 and is the subject of today's Google Doodle—had a lifelong interest in the paranormal, once commenting that he thought it was “wonderful” that it was still “undecided whether or not there has ever been an instance of the spirit of any person appearing after death. All argument is against it, but all belief is for it.” According to Boswell, however, he was more of a skeptic than an out-and-out believer, and refused to accept anything without seeing the evidence for himself. So when the news broke of an apparently haunted house just a few streets away from his own home in central London, Johnson jumped at the chance to perhaps see a ghost with his own eyes.

The haunting began in the early 1760s, when a young couple, William and Fanny Kent, began renting a room from a local landlord, Richard (or William—sources disagree, but for clarity, we'll use Richard) Parsons, at 25 Cock Lane in Smithfield, London. Soon after the Kents moved in, Richard’s daughter, Betty, began to hear strange knocking and scratching sounds all around the house, and eventually claimed to have seen a ghost in her bedroom.

Richard soon discovered that William was a widower and that Fanny was in fact his deceased wife's sister; under canon law, the pair couldn't be married, and Richard became convinced that the ghost must be that of William's deceased first wife, Elizabeth, blaming William’s presence in the house for all of the strange occurrences. He promptly evicted the Kents and the noises soon subsided—but when Fanny also died just a few weeks later, they immediately resumed and again seemed to center around Betty. In desperation, a series of séances were held at the Cock Lane house, and finally Fanny’s ghost supposedly confirmed her presence by knocking on the table. When questioned, Fanny claimed that William had killed her by poisoning her food with arsenic—an accusation William understandably denied.

By now, news of the Cock Lane Ghost had spread all across the city, and when the story broke in the press, dozens of curious Londoners began turning up at the house, queuing for hours outside in the street hoping to see any sign of supernatural activity. According to some accounts, Parsons even charged visitors to come in and “talk” to the ghost, who would communicate with knocks and other disembodied noises.

But with the suspicion of murder now in the air, the Cock Lane haunting changed from a local curiosity into a full-blown criminal investigation. A committee was formed to examine the case, and Johnson was brought in to record their findings and investigate the case for himself.

On February 1, 1762, one final séance was held with all members of the committee—Johnson included—in attendance. He recorded that:

About 10 at night the gentlemen met in the chamber in which the girl [Betty] supposed to be disturbed by a spirit had, with proper caution, been put to bed by several ladies. They sat rather more than an hour, and hearing nothing, went down stairs, when they interrogated the father of the girl, who denied, in the strongest terms, any knowledge or belief of fraud … While they were enquiring and deliberating, they were summoned into the girl’s chamber by some ladies who were near her bed, and who had heard knocks and scratches. When the gentlemen entered, the girl declared that she felt the spirit like a mouse upon her back.

But the committee were suspicious. Betty was asked to hold out her hands in front of her, in sight of everyone in the room:

From that time—though the spirit was very solemnly required to manifest its existence by appearance, by impression on the hand or body of any present, by scratches, knocks, or any other agency—no evidence of any preternatural power was exhibited.

Johnson ultimately concluded that it was “the opinion of the whole assembly that the child has some art of making or counterfeiting a particular noise, and that there is no agency of any higher cause.” And he was right.

As the investigation continued, it was eventually discovered that Richard Parsons had earlier borrowed a considerable amount of money from William Kent that he had no means (nor apparently any intention) of repaying. The two men had a falling out, and Parsons set about elaborately framing Kent for both Fanny and Elizabeth's deaths. The ghostly scratching and knocking noises had all been Betty’s work; she hidden a small wooden board into the hem of her clothing with which to tap or scratch on the walls or furniture when prompted.

The Parsons—along with a servant and a preacher, who were also in on the scam—were all prosecuted, and Richard was sentenced to two years in prison.

Although the Cock Lane haunting turned out to be a hoax, Johnson remained open minded about the supernatural. “If a form should appear,” he later told Boswell, “and a voice tell me that a particular man had died at a particular place, and a particular hour, a fact which I had no apprehension of, nor any means of knowing, and this fact, with all its circumstances, should afterwards be unquestionably proved, I should, in that case, be persuaded that I had supernatural intelligence imparted to me.”

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The King of Kong © Jim Naughten. Courtesy of Michael Hoppen Gallery
The Mountains of Kong: The Majestic West African Range That Never Existed
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The King of Kong © Jim Naughten. Courtesy of Michael Hoppen Gallery

If you look closely at a 19th century map of Africa, you’ll notice one major way that it differs from contemporary maps, one that has nothing to do with changing political or cartographical styles. More likely than not, it features a mountain range that no longer appears on modern maps, as WIRED explains. Because it never existed in the first place.

A 19th century map of West Africa
From Milner's Descriptive Atlas, 1850

The “Mountains of Kong” appeared on almost every major commercial map of Africa in the 1800s, stretching across the western part of the continent between the Gulf of Guinea and the Niger River. This mythical east-west mountain range is now the subject of an art exhibition at London’s Michael Hoppen Gallery.

In "Mountains of Kong," stereoscopic images by artist Jim Naughten—the same format that allowed Victorians with wanderlust to feel like they’d seen the world—reveal his view of the world of wildlife that might have existed inside the imagined mountains. As the gallery describes it, “he imagines a fictitious record made for posterity and scientific purposes during an expedition of the mountain range.” We’ve reproduced the images here, but to get the full effect, you’ll have to go to the gallery in person, where you can view them in 3D with a stereoscope (like the ones you no doubt played with as a kid).

Toucans fight a snake in two almost-identical side-by-side images.
The Toucans © Jim Naughten. Courtesy of Michael Hoppen Gallery

Naughten created the images by taking two photographs for each, and moving the camera over some 3 inches for the second photo to make a stereoscopic scene. The landscapes were created by shooting images of Scottish and Welsh mountains and dioramas in natural history museums, using Photoshop to change the hues of the images to make them seem more otherworldly. His blue-and-pink-hued images depict fearsome apes, toucans sparring with snakes, jagged peaks, and other scenes that seem both plausible and fantastical at the same time.

The Mountains of Kong appeared in several hundred maps up until the 20th century. The first, in 1798, was created by the prominent geographer James Rennell to accompany a book by Scottish explorer Mungo Park about his first journey to West Africa. In it, Park recounts gazing on a distant range, and “people informed me, that these mountains were situated in a large and powerful kingdom called Kong.” Rennell, in turn, took this brief observation and, based on his own theories about the course of the Niger River, drew a map showing the mountain range that he thought was the source of the river. Even explorers who later spent time in the area believed the mountains existed—with some even claiming that they crossed them.

Two colobuses stand in a tree on a mountaintop.
The Colobus © Jim Naughten. Courtesy of Michael Hoppen Gallery

The authority of the maps wasn’t questioned, even by those who had been to the actual territory where they were depicted as standing. Writers began to describe them as “lofty,” “barren,” and “snow-covered.” Some said they were rugged granite peaks; others described them as limestone terraces. In almost all cases, they were described as “blue.” Their elevation ranged from 2500 feet to 14,000 feet, depending on the source. Over the course of the 19th century, “there was a general southward ‘drift’ in the location,” as one pair of scholars put it.

Though geographers cast some doubt on the range’s existence as time went on, the Mountains of Kong continued to appear on maps until French explorer Louis-Gustave Binger’s Niger River expedition between 1887 and 1889, after which Binger definitively declared their nonexistence.

By 1891, the Mountains of Kong began dropping off of maps, though the name Kong still appeared as the name of the region. By the early 20th century, the mountains were gone for good, fading into the forgotten annals of cartographic history.

[h/t WIRED]

All images courtesy Michael Hoppen Gallery.


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