Mental Floss

BIG QUESTIONS

Jason's Phone

Let’s picture a typical moment in my day: I’m minding my own business, with my iPhone in my back pocket. Suddenly, my left cheek is shaking as the phone vibrates and does the bzzt, bzzt, bzzt-ing dance of its people on my backside. I check the phone, and

Matt Soniak
istock.com/rzelich

The very first traffic light, installed outside the Houses of Parliament in London in December 1868, had red and green gas lamps for nighttime use. The device was pretty crude, and less than a month after it went operational, it exploded and killed the un

Matt Soniak

( )Parentheses (the single one is called a parenthesis), also known as curved brackets, have plenty of uses in everyday written language. Their most common use, as I’ve demonstrated already, is segregating subordinate material or asides. Usually, this is

Matt Soniak




Eric Huang, Flickr // CC BY-NC-ND 2.0

Some Dum Dums have wrappers with question marks where the flavor is normally printed. This was a marketing idea that made the production process run more smoothly and made eating Dum Dums more fun.

Sandy and Kara




Truman isn’t just gleeful in that famous photo because he won the election, but because it was egg on the face of a paper he hated, the Chicago Tribune. The paper had a conservative bent, disapproved of most of his policies, and had once even called him a

Kathy Benjamin
istock.com/LauriPatterson

The sugars in beans are far too big to slip though the intestinal wall on their own, and our guts’ enzymatic tool kit doesn’t have the right stuff to break the big things apart into more manageable pieces.

Matt Soniak
iStock/milla1974

Well, they're not dyed for St. Patrick’s Day. These are just from potatoes in which chlorophyll had started to form. This can happen when potatoes, which grow underground, are exposed to too much light in the field or factory, in storage, on the store she

Matt Soniak

LOUIS LANZANO/Landov The short answer: no.The long answer: Once upon a time, being presented with the key to the city served a real function. In ancient times, when it was common for European towns to be ringed by walls, visiting dignitaries were presente

Stacy Conradt


istock.com/SPmemory

While the lifespan of any individual atom is random and unpredictable, the probability of decay is constant. You can’t predict when an unstable atom will break down, but if you have a group of them, you can predict how long it will take.

Matt Soniak


Sledding image via Shutterstock“Put a jacket on if you’re going out there, or you’ll catch a cold.”It’s a common refrain of grandmothers all over the world. Are they right, though? Do low temperatures have anything to do with catching the common cold? Mos

Matt Soniak


The Duke of Windsor marries Wallis Simpson in 1937.

In the 1930s, how would a middle-class Baltimore divorcee become romantically involved with the man who would be King of England? It always comes down to who you know. And Wallis Simpson knew how to climb the social ladder very effectively.

Kathy Benjamin


vchal/iStock via Getty Images

I know I’m only about a decade late, but I recently, finally, watched the entire run of The Sopranos. Tony and his crew get their hands into plenty of different moneymaking schemes, but throughout the series one character or another (Tony, Richie Aprile,

Matt Soniak

Smelling image via ShutterstockI’m perfectly suited to answer the Big Question that reader Katie posed the other day, because I have anosmia, which means I can’t smell. At all. Every diaper my two-year-old has ever filled has been totally odorless to me.

Stacy Conradt

Image credit: NASALet's start with the bad news: Remember that hole in the ozone layer that scientists discovered over the Antarctic in 1985? The one we worried would give us all skin cancer and cataracts with its unshielded bursts of UV rays? It’s still

Ethan Trex
tuu Sitthikorn/iStock via Getty Images

The hose that attaches the nozzle to the gas pump is designed to break into two pieces when a certain amount of force is applied to it. Next time you’re at the gas station, check the hose for a metal coupling.

Matt Soniak


Quicksand is a staple hazard of adventure movies, TV shows and video games. Whenever a minor character needs to be killed off quickly, the hero needs someone to rescue, or danger needs to be introduced without calling the villain in, quicksand is there to

Matt Soniak


Vonschonertagen/iStock via Getty Images

Paper cut image via ShutterstockThere are a couple things at play here, some involving the paper, some involving your skin. For one thing, what part of your body comes in contact with paper the most?

Matt Soniak




istock.com/ByronOrtizA

Some animals have it made. Their whole day revolves around eating and having sex (and, to be fair, trying not to get eaten themselves). And when winter arrives, they get to curl up somewhere and wait things out until the weather is nice again. Can humans

Matt Soniak
inga/iStock via Getty Images

Trauma, that’s what. It’s the smell of chemical defenses and first aid. The fresh, “green” scent of a just-mowed lawn is the lawn trying to save itself from the injury you just inflicted.

Matt Soniak

Adam's apple photo via ShutterstockTouch your fingers to the front of your throat and start humming. Feel around until you can feel vibration directly under your fingers. That’s your larynx, or voice box. It houses your vocal cords and is involved in brea

Matt Soniak