What Causes Sinkholes?

Mark Ralston/AFP/Getty Images
Mark Ralston/AFP/Getty Images

This week, a sinkhole opened up on the White House lawn—likely the result of excess rainfall on the "legitimate swamp" surrounding the storied building, a geologist told The New York Times. While the event had some suggesting we call for Buffy's help, sinkholes are pretty common. In the past few days alone, cavernous maws in the earth have appeared in Maryland, North Carolina, Tennessee, and of course Florida, home to more sinkholes than any other state.

Sinkholes have gulped down suburban homes, cars, and entire fields in the past. How does the ground just open up like that?

Sinkholes are a simple matter of cause and effect. Urban sinkholes may be directly traced to underground water main breaks or collapsed sewer pipelines, into which city sidewalks crumple in the absence of any structural support. In more rural areas, such catastrophes might be attributed to abandoned mine shafts or salt caverns that can't take the weight anymore. These types of sinkholes are heavily influenced by human action, but most sinkholes are unpredictable, inevitable natural occurrences.

Florida is so prone to sinkholes because it has the misfortune of being built upon a foundation of limestone—solid rock, but the kind that is easily dissolved by acidic rain or groundwater. The karst process, in which the mildly acidic water wears away at fractures in the limestone, leaves empty space where there used to be stone, and even the residue is washed away. Any loose soil, grass, or—for example—luxury condominiums perched atop the hole in the ground aren't left with much support. Just as a house built on a weak foundation is more likely to collapse, the same is true of the ground itself. Gravity eventually takes its toll, aided by natural erosion, and so the hole begins to sink.

About 10 percent of the world's landscape is composed of karst regions. Despite being common, sinkholes' unforeseeable nature serves as proof that the ground beneath our feet may not be as solid as we think.

A version of this story originally ran in 2014.

Why is Winnie the Pooh Called a Pooh?

iStock.com/CatLane
iStock.com/CatLane

Since A.A. Milne published the first official Winnie the Pooh story in 1926, the character has become beloved by children across many generations. Milne’s writing clearly struck a chord, and the character’s many subsequent TV and film adaptations have endeared him to an even wider audience.

But why is Winnie called a Pooh rather than a bear? Given that most children (and grown-ups, for that matter) have a different idea of what a Pooh is, how has the name stuck?

The answer lies back in the 1920s.

In fact, when first introduced by Milne, Winnie wasn’t even Winnie. Initially, he went by the name of Edward Bear, before changing to Winnie in time for that aforementioned official 1926 debut. The "Winnie" part of the name came from a visit to the London Zoo, where Milne saw a black bear who had been named after the city of Winnipeg, Canada.

As for Pooh? Well, originally Pooh was a swan, a different character entirely.

In the book When We Were Very Young (the same book that introduced Edward Bear), Milne wrote a poem, telling how Christopher Robin would feed the swan in the mornings.

He told how Christopher Robin had given the swan the name "Pooh," explaining that “this is a very fine name for a swan, because if you call him and he doesn’t come (which is a thing swans are good at), then you can pretend that you were just saying ‘Pooh!’ to show him how little you wanted him."

Milne indeed knew what he was doing by using such a word. The names "Winnie" and "Pooh" were soon brought together, and Winnie the Pooh was born. Milne still took a little time out to explain why Winnie was a Pooh, though.

As he would write in the first chapter of the first Winnie the Pooh book, “But his arms were so stiff ... they stayed up straight in the air for more than a week, and whenever a fly came and settled on his nose he had to blow it off. And I think—but I am not sure—that that is why he is always called Pooh."

It's not the most convincing explanation, but it's a formal explanation nonetheless.

Not that the reasoning ultimately mattered too much. The name stuck, having never seen a focus group in its life. A much loved childhood character, with a vaguely funny name, would go on to superstardom. And even be honored with his own holiday, Winnie the Pooh Day, which occurs annually on January 18th.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

Why is Winnie the Pooh Called a Pooh?

iStock.com/CatLane
iStock.com/CatLane

Since A.A. Milne published the first official Winnie the Pooh story in 1926, the character has become beloved by children across many generations. Milne’s writing clearly struck a chord, and the character’s many subsequent TV and film adaptations have endeared him to an even wider audience.

But why is Winnie called a Pooh rather than a bear? Given that most children (and grown-ups, for that matter) have a different idea of what a Pooh is, how has the name stuck?

The answer lies back in the 1920s.

In fact, when first introduced by Milne, Winnie wasn’t even Winnie. Initially, he went by the name of Edward Bear, before changing to Winnie in time for that aforementioned official 1926 debut. The "Winnie" part of the name came from a visit to the London Zoo, where Milne saw a black bear who had been named after the city of Winnipeg, Canada.

As for Pooh? Well, originally Pooh was a swan, a different character entirely.

In the book When We Were Very Young (the same book that introduced Edward Bear), Milne wrote a poem, telling how Christopher Robin would feed the swan in the mornings.

He told how Christopher Robin had given the swan the name "Pooh," explaining that “this is a very fine name for a swan, because if you call him and he doesn’t come (which is a thing swans are good at), then you can pretend that you were just saying ‘Pooh!’ to show him how little you wanted him."

Milne indeed knew what he was doing by using such a word. The names "Winnie" and "Pooh" were soon brought together, and Winnie the Pooh was born. Milne still took a little time out to explain why Winnie was a Pooh, though.

As he would write in the first chapter of the first Winnie the Pooh book, “But his arms were so stiff ... they stayed up straight in the air for more than a week, and whenever a fly came and settled on his nose he had to blow it off. And I think—but I am not sure—that that is why he is always called Pooh."

It's not the most convincing explanation, but it's a formal explanation nonetheless.

Not that the reasoning ultimately mattered too much. The name stuck, having never seen a focus group in its life. A much loved childhood character, with a vaguely funny name, would go on to superstardom. And even be honored with his own holiday, Winnie the Pooh Day, which occurs annually on January 18th.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

SECTIONS

arrow
LIVE SMARTER