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Why roller coasters need three kinds of wheels
Culture & entertainment

Why roller coasters need three kinds of wheels

Defying gravity requires an aggressively paranoid wheel assembly. Every single cart utilizes a main wheel to roll, a side wheel to stop lateral shaking, and…

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Why using a public restroom may require a purchase
Economy

Why using a public restroom may require a purchase

Cities stopped building public facilities, effectively outsourcing basic human biological needs to coffee shops and fast food chains. If you want to use a…

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Mirrors were covered during storms to deflect lightning
Myths & mysteries

Mirrors were covered during storms to deflect lightning

Ah yes, throwing a thin sheet over reflective glass is the ultimate defense against millions of volts of electricity. Historically, households panicked that…

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Gideons International distributes most hotel room Bibles
Travel

Gideons International distributes most hotel room Bibles

Hotels aren't inherently religious establishments pushing scripture. An aggressively organized external association operates a massive free distribution…

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A wrong resistor helped invent the pacemaker
Technology

A wrong resistor helped invent the pacemaker

A tiny mistake revolutionized cardiology forever. A researcher reached for a resistor to complete a circuit for recording heartbeats, grabbed the wrong size,…

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Norovirus may take only 10 particles
Health

Norovirus may take only 10 particles

Most diseases require a massive microscopic army to successfully breach human defenses and establish a miserable foothold. This wildly contagious…

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The blank space where comics make you imagine the violence
Culture & entertainment

The blank space where comics make you imagine the violence

The blank white space between comic panels is officially called the gutter, and it's where the actual violence happens. Because the artist only draws the…

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Waterfalls flowing backwards happen due to extreme winds
Myths & mysteries

Waterfalls flowing backwards happen due to extreme winds

When atmospheric gales hit massive coastal cliffs perfectly, the descending water gets violently shoved straight back up into the sky. It is a stunning visual…

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Roman soldiers trained with a giant game of hopscotch
Games

Roman soldiers trained with a giant game of hopscotch

Instead of drawing with chalk, Roman soldiers jumped through massive courts wearing full armor to build leg strength. Because nothing prepares you for…

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Labyrinths on cathedral floors trapped wandering forces
Myths & mysteries

Labyrinths on cathedral floors trapped wandering forces

Massive tile mazes weren't just for exhausting the local congregants. They supposedly forced any unseen negative vibes into a confusing geometric puzzle,…

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Why old books have gold-edged pages
Culture & entertainment

Why old books have gold-edged pages

That stunning, shiny gold leaf slathered on the edges of a fancy hardcover isn't just a desperate cry for aesthetic attention. It originally served a deeply…

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Superhero continuities are constantly rebooted out of panic
Culture & entertainment

Superhero continuities are constantly rebooted out of panic

After decades of overlapping storylines, alternate dimensions, and resurrected characters, maintaining a coherent timeline becomes mathematically impossible.…

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How iodized salt stopped goiters
Health

How iodized salt stopped goiters

One of the most successful public health initiatives in modern history simply involved sprinkling a microscopic amount of a trace element into a universal…

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Sailors wore gold earrings to pay for unexpected fees
Myths & mysteries

Sailors wore gold earrings to pay for unexpected fees

Instead of carrying a wallet, seafarers just bolted their savings directly to their heads. If they washed up somewhere unfamiliar, that precious metal hoop…

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Three-dimensional books rely on complex tab-and-slot physics
Culture & entertainment

Three-dimensional books rely on complex tab-and-slot physics

Opening a children's pop-up book triggers a highly sophisticated feat of mechanical engineering. The aggressive unfolding of a cardboard dragon relies…

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Zika virus was identified in the nineteen forties
Health

Zika virus was identified in the nineteen forties

When this terrifying mosquito-borne illness sparked a massive global panic a few years ago, the media treated it like a brand new apocalyptic menace. In…

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Wax figures use real human hair
Travel

Wax figures use real human hair

Achieving lifelike realism requires crossing a seriously unsettling line. Artisans individually insert strands of actual, ethically sourced human hair into…

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Invading personal space bubbles causes intense tension
Psychology

Invading personal space bubbles causes intense tension

Standing slightly too close in an elevator is an act of psychological warfare. Proxemics studies our invisible, fiercely defended territorial bubbles. When a…

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