1

The horse diaper

Image: Lucia Macedo

Designed to catch manure in crowded cities—a problem once so severe that it shaped public infrastructure as well as the entrances to houses—the horse diaper was an invention meant to be strapped beneath working horses pulling carts and carriages.

The idea was to reduce disease and street filth during the horse-powered urban era. While the device saw limited use before automobiles rapidly replaced horses, similar designs are still occasionally used in modern veterinary practice.

2

The baby cage

Image: Taylor Flowe

Built as wire cages attached to apartment windows, so-called "baby cages" allowed infants to get fresh air when outdoor space was unavailable. Some models were guaranteed to safely hold over 30 pounds.

While alarming today and ultimately abandoned due to obvious safety concerns, the designs likely inspired some of the baby-proofing nets used today.

3

The pneumatic subway

Image: Eddi Aguirre

In the late 1860s, American entrepreneur and inventor Alfred Ely Beach set out to prove the feasibility of a human-sized pneumatic subway system beneath New York City, capable of moving both people and cargo using nothing more than air pressure.

The prototype was set up as a public attraction and carried passengers along a tunnel just over 300 feet long, from a station to a dead end. Despite its initial success, bureaucratic obstacles and high costs halted expansion, leaving it as a functional but largely forgotten underground experiment.

4

The mechanical horse

Image: Gabriel Tovar

Created for exercise and riding practice, the mechanical horse used a system of gears, cranks, and pedals to simulate walking and trotting motions while the rider sat in a saddle-like seat. It was marketed to urban riders and cavalry trainees who lacked access to stables or live horses.

Though bulky and impractical for widespread use, the device anticipated modern fitness machines by replicating real-world movements for conditioning and skill retention, rather than simple repetitive exercise.

5

The first metal detector

Image: Fer Troulik

After a failed assassination attempt on President James Garfield, Alexander Graham Bell hastily built an early metal detector in an effort to locate the bullet lodged in his body. The device functioned as intended, but it was unable to find the bullet because metal bed springs interfered with the signal.

Despite this setback, Bell’s early design proved the concept and directly influenced the development of modern metal detectors.

6

The pet-powered butter churn

Image: Matt Bero

In an inventive twist on animal-powered machinery, some 19th-century American farmers rigged small treadwheels for dogs, cats, or even goats to generate kinetic energy for churning butter. The animal ran inside the wheel, turning a rope or pulley connected to the churn.

While technically functional, the system was limited by the animal's willingness to cooperate and the small amount of power it generated.

7

The umbrella hat

Image: Claudio Schwarz

Robert W. Patten, often called the "Umbrella Man," patented one of the first commercially successful hands-free umbrella hats. It strapped a small umbrella directly to the wearer’s head, providing both sun and rain protection while keeping the hands free for work or walking.

His original design even included a mosquito net attached to the canopy. Patten didn’t enjoy much commercial success but became somewhat of an eccentric and comical popular figure, partly due to a series of comics that were inspired by his unusual invention.

8

The one-wheel motorcycle

Image: CJ Toscano

In 1971, American inventor Kerry McLean built and refined a monowheel—a one‑wheeled motorized vehicle in which the rider and engine sit inside the wheel’s circumference.

Since then, various attempts have been made to build on his original design, but it remains a niche vehicle used primarily for entertainment rather than practicality, as riders must be highly skilled simply to turn or even stay upright.

9

The first talking doll

Image: Holly Ward

In 1890, Thomas Edison embedded miniature versions of one of his most popular inventions —the phonograph—inside dolls so they could recite nursery rhymes.

While the idea was innovative, the technology was not yet there. The recordings were fragile, distorted, and often failed to work properly. The dolls were pulled from the market within weeks due to customer complaints, making it one of Edison’s rare commercial failures.

10

The glass harmonica

Image: Francesco Bovolin

Faithful to his eccentricity and inventive spirit, Benjamin Franklin redesigned the existing glass harp into a rotating spindle of glass bowls, played by touching the spinning rims with wet fingers, which he called the "glass harmonica."

The instrument produced eerie, sustained tones unlike anything else of its era. However, its fragile nature made it somewhat impractical, and the rotating mechanism posed a potential danger to the player if anything went wrong.

1

The original plan included full-body figures

Image: Thomas Shockey

Mount Rushmore was supposed to be even more colossal than it already is. Sculptor Gutzon Borglum envisioned the four presidents carved from the waist up .

He even made plaster models showing Abraham Lincoln's coat folds and Teddy Roosevelt’s hand clutching his lapel. But as costs went up, Congress said: "heads only, please."

2

Charles Rushmore was just a curious New Yorker

Image: Maarten van den Heuvel

Back in 1925, when the mount was about to be carved into a monument, Charles Rushmore wrote a letter explaining why the peak bore his name. He recalled that in the 1880s he was a young New Yorker working in the area, and fell fond of that particular granite peak .

When he asked the locals about it, they informed him that it had no name, but that if he wished so, they would just start calling it Rushmore Peak, or Mount Rushmore, or the likes. Years later, that very name had been inscribed in the public domain to designate the peak.

3

Yes, there’s a hidden room behind Lincoln’s head

Image: Laura Nyhuis

Behind Abraham Lincoln’s hairline lies a hidden chamber, part of Borglum’s lofty idea for a "Hall of Records." This room was meant to house foundational American documents like the Constitution or the Declaration of Independence.

Instead of that, in 1998, a titanium box was placed inside, filled with copies of important documents and biographies, as a time capsule to preserve the treasure of knowledge for future generations.

4

Thomas Jefferson was moved

Image: Dave Baraloto

Jefferson was originally supposed to go to Washington’s right, but after 18 months of chiseling , the granite betrayed them. Cracks and flaws made the site unworkable.

Borglum made the painful decision to blast Jefferson’s half-formed face clean off and start anew on Washington’s left.

5

The mountain was almost a monument to western heroes

Image: Timberly Hawkins

Before presidents took over, the mountain was pitched as a giant tribute to the Wild West . South Dakota historian Doane Robinson wanted to see frontier legends like Lewis & Clark carved into the Black Hills.

But when Borglum came aboard, he had a grander (and more politically bankable) idea: four presidents to symbolize national unity and expansion.

6

A woman’s face was almost added

Image: Tom Fournier

In the 1930s, there was serious talk of honoring Susan B. Anthony alongside the Founding Fathers, as a nod to the women’s suffrage movement.

Borglum wasn’t opposed to the idea, but Congress quickly nixed it, stating that only U.S. presidents could be included.

7

The workers were mostly local miners and loggers

Image: Pixabay

They were neither sculptors nor artists. Most of the workforce came from nearby Keystone, South Dakota: miners, loggers, and hard-up laborers looking for work during the Great Depression.

Borglum trained them himself. There were no safety harnesses, and yet, remarkably, no one died on the job.

8

Dynamite did 90% of the work

Image: Alexander Paramonov

To carve the faces of Washington, Jefferson, Roosevelt, and Lincoln, workers used carefully timed dynamite blasts to remove over 450,000 tons of rock. They got so precise, they could blast within inches of where the final surface would be.

The last details, like wrinkles, pupils, or Roosevelt’s glasses, were done with jackhammers and chisels.

9

The noses are disproportionate

Image: Dudubangbang Travel

Standing in front of the mountain, the faces seem alright. But that’s a trick of perspective. Each presidential nose is a whopping 20 feet long .

If the sculptures had included full bodies as planned, each figure would have stood 465 feet tall. That’s taller than the Statue of Liberty and most downtown skyscrapers.

10

Teddy Roosevelt was the most controversial pick

Image: Dudubangbang Travel

Washington, of course. Jefferson, made sense. Lincoln, sure. And Teddy? Some critics raised their eyebrows at Borglum’s fourth choice. Roosevelt had only recently passed away in 1919, and many questioned whether he'd stood the test of time.

But Borglum defended the decision Roosevelt’s role in breaking up monopolies, conserving national parks, and engineering the Panama Canal. Plus, Borglum had met him personally and was a fan.

11

It was supposed to have inscriptions

Image: Dan Pick

Borglum had grander plans than just four giant heads. He wanted to carve a massive inscription next to them, a timeline of America’s most important milestones , chiseled straight into the mountain. In time, the idea was scrapped for practical and aesthetic reasons.

12

The visionary died before completion

Image: Lisa Reichenstein

Gutzon Borglum, the visionary behind it all, didn’t live to see his masterpiece finished. He died in March 1941, just as the construction was reaching its end. His son, Lincoln Borglum (yes, named after that Lincoln), took over the project.

Still, with WWII drawing resources elsewhere, funding was slashed, and Lincoln had to wrap things up quickly . Some features, like Lincoln’s ear, were never fully detailed.

1

$125 million for a Grade-school math error

Image: Aaron Lefler

Imagine losing a hugely expensive spacecraft due to a simple mix-up between English and metric measurements . That is exactly what happened to NASA in 1999 when a Mars orbiter designed by Lockheed Martin was lost in space.

The confusion caused a malfunction on the $125 million craft, resulting in the probe’s loss. Although it was unusual for Lockheed to use English measurements for a NASA design (since NASA had stipulated using metric measurements for many years), there were still several instances where the error should have been caught but wasn’t.

2

Toys ‘R’ Us blunder

Image: Taylor Heery

If you think an action figure of a drug dealer isn’t the best idea for a toy store , you’re not alone. Yet, for some reason, Toys "R" Us decided otherwise in October 2014, possibly hoping to cash in on the massive success of the Breaking Bad TV series.

Unsurprisingly, the giant toy retailer was forced to pull from its shelves four collectible dolls based on characters from the AMC hit show, each doll featuring a detachable sack of cash and a bag of meth.

3

Apple Maps' rocky beginnings

Image: CardMapr.nl

When Apple decided to launch its own map application on iOS devices after a conflict with Google in 2012, users quickly realized that the Apple app was not nearly as launch-ready as it should have been .

Locations were mislabeled, roads were missing, and it occasionally steered people in entirely the wrong direction. The problem was eventually, though largely, resolved, but it was an embarrassing misstep for a company known for never launching a product before it was as near-perfect as possible.

4

Bank of America debit card fee

Image: Ali Mkumbwa

Back in 2011, when the backlash against the banking industry had not yet reached its boiling point, Bank of America announced it would charge customers $5 per month to use their debit cards .

It was a bad business decision. More than 300,000 people signed an online petition, and Fox Business Network’s Gerri Willis cut up her debit card on air. The bank pointed to federal regulations as the reason for the charge but ultimately capitulated to consumer demand after a month before the fees went into effect.

5

$33 airline tickets from Toronto to Cyprus

Image: Miguel Ángel Sanz

If buying a business class ticket regularly priced at $2,558 for just $33 sounds too good to be true, it probably is. Except in 2006, when an Alitalia employee accidentally forgot to input two extra zeros when pricing business-class tickets from Toronto to Cyprus.

Due to the exchange rate on that day and the blunder, hundreds of buyers managed to snag fares for just $33. The airline honored those deals, accepting the heavily discounted price for the 509 people who purchased tickets before the error was detected.

6

A $70 million comma

Image: Nattipat Vesvarute

As the folks at NASA and Alitalia have shown us, small errors can lead to costly mistakes. The following blunder comes courtesy of Lockheed Martin , which issued a contract to a customer with a missing comma in the sale price .

The astute customer held the aerospace company to the contract, costing Lockheed Martin $70 million for a C-130J Hercules aircraft in June 1999.

7

Sears misses the ship

Image: Estefania Cortes

A retail giant that faced a situation similar to the one Kodak faced—embrace the new and unknown or cling to the old, successful recipe—Sears sold everything from socks to tires via mail order, shipping across the U.S.

Choosing to stick with the old method, the company ended its catalog and delivery business in 1993 . In 1994, Amazon was founded , filling the business void that Sears had just created. The rest is history.

8

Passing on Microsoft

Image: Jaime Marrero

$60 million might seem like a lot of money to us regular folks, but for someone with very deep pockets like Texas businessman and two-time U.S. presidential candidate Ross Perot, it wasn’t all that much.

In 1979, he was offered the chance to buy Microsoft for that sum. However, his final offer to the tech company was just $15 million, and as a result, the Texan missed out on the opportunity to own what would become one of the biggest companies in the world .

9

Blackberry sticks with the old

Image: Thai Nguyen

Another case of a brand sticking with the old instead of embracing the new, BlackBerry was all the rage at the start of the 21st century— until Steve Jobs came along with the Apple iPhone .

While BlackBerry Messenger was extremely popular, with over 80 million users worldwide, the device lacked the new touchscreen functionality and sleek design of the Apple product. From being a market leader, BlackBerry’s market share plummeted to 0.2% by 2016.

10

RadioShack’s downfall

Image: Jelleke Vanooteghem

Not so long ago, RadioShack was a familiar presence on the streets and the go-to place for buying batteries and electronics. But it was that same brick-and-mortar presence, coupled with a reluctance to embrace e-commerce , that ultimately led to its demise .

Eventually, poor profit margins on what they could sell, combined with a loan they couldn’t repay, brought down what was once the go-to place for electronics.