Robert Cianflone/Getty Images
Robert Cianflone/Getty Images

What Exactly Is Curling?

Robert Cianflone/Getty Images
Robert Cianflone/Getty Images

Olympic curling has taken to the ice, but if you're like most Americans, this writer included, the game is a bit baffling. Here's a quick, stripped-down primer on everyone's favorite icy alternative to shuffleboard. It doesn't cover anywhere near all of the game's nuances, but it should give you enough info that you can enjoy watching an end or two. (And yes, you'll learn what an "end" is.)


Good question. First, let's get a bit of the jargon down. The playing surface in curling is called "the sheet." Sheet dimensions can vary, but they're usually around 150 feet long by about 15 feet wide. The sheet is covered with tiny droplets of water that become ice and cause the stones to "curl," or deviate from a straight path. These water droplets are known as "pebble."

At each end there's a target that looks like a big bullseye. These targets are known as "the houses." The center of the house is known as the "button." Basically, the object of the game is to get your stones closer to the button than the other team gets theirs.


How Curling Works
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Remember how we talked about the pebble of ice droplets that the rock has to travel across? When the stone touches the pebble, there's friction, which can slow down the stone and makes it curl away from its straight path to the house.

Obviously, that friction is not always a good thing, but sweeping helps combat the problem. The sweeping motion raises the temperature of the ice by a degree or two, which diminishes the friction between the pebble and the stone and keeps the stone moving in a straight line.


Each curling team has four members: a lead, a second, a vice-skip (or third), and a skip. Each "end" (curling's equivalent of a baseball inning) involves both teams shooting (or "delivering") eight stones at the house, with players delivering two stones apiece.

When the lead, second, and vice are delivering their stones, the skip stands at the opposite end of the sheet (near the house) and uses his broom to give his teammates a target for their deliveries. Once the stone has been delivered and is a "running stone" (that is, one that's still sliding), the skip then yells to the sweepers to let them know when to sweep and how hard. When the skip shoots the last two stones of a team's end, the vice takes over calling the shots.


In each end, both teams send eight stones down the sheet. Once all 16 stones have been delivered, the team with the stone that's closest to the button (center of the house) effectively "wins" the end. Only this team will earn any points for the end. It gets a point for each of its stones that are in the house and closer to the button than the other team's closest stone. Since the team that won the end always has at least one stone that's closer to the button than their opponent, the team always scores at least one point, and could score up to eight points.

If neither team manages to keep a stone in the house during an end, it's known as a "blank end," and no points are scored. Olympic curling matches last for 10 ends unless there is a tie, in which case it goes to extra-ends, curling's equivalent of overtime.


As you might have guessed from reading about the scoring system, throwing the last stone of an end is a huge advantage. If you've got the last stone, you can always try to knock the other team's best stone away from the button. If a team holds the last stone for an end, it "has the hammer," and should probably be able to score some points. If the team without the hammer manages to somehow stymie their opponent and score points, it's called a "stolen end." Whichever team fails to score points in an end gets the hammer for the next end.


Yes, there's all sorts of strategy in curling. Let's say your team doesn't have the hammer. You're at a huge disadvantage when it comes to scoring points, so you might opt to play defensively. To do that, you might just deliver a number of "guards," or rocks that will sit in front of the house and provide an obstacle for the other team's stones. Alternatively, guards can be used to defend your stones that are already in the house from being knocked out by the other team's "takeout" shots.

The third major type of curling shot is the "draw," a shot that's meant to avoid other stones and come to rest in the house. Generally, a draw is used with the hope of scoring points, a guard is thrown to protect the house or a stone that's already been thrown, and a takeout is used defensively.


Yes you may.

This post was originally published in 2010.

Big Questions
Why Are There No Snakes in Ireland?

Legend tells of St. Patrick using the power of his faith to drive all of Ireland’s snakes into the sea. It’s an impressive image, but there’s no way it could have happened.

There never were any snakes in Ireland, partly for the same reason that there are no snakes in Hawaii, Iceland, New Zealand, Greenland, or Antarctica: the Emerald Isle is, well, an island.

Eightofnine via Wikimedia Commons // Public Domain

Once upon a time, Ireland was connected to a larger landmass. But that time was an ice age that kept the land far too chilly for cold-blooded reptiles. As the ice age ended around 10,000 years ago, glaciers melted, pouring even more cold water into the now-impassable expanse between Ireland and its neighbors.

Other animals, like wild boars, lynx, and brown bears, managed to make it across—as did a single reptile: the common lizard. Snakes, however, missed their chance.

The country’s serpent-free reputation has, somewhat perversely, turned snake ownership into a status symbol. There have been numerous reports of large pet snakes escaping or being released. As of yet, no species has managed to take hold in the wild—a small miracle in itself.

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Big Questions
How Do They Dye the Chicago River Green for St. Patrick's Day?

It wouldn’t be a St. Patrick’s Day celebration in the Windy City without 400,000 spectators crowding the banks of the Chicago River to “ooh” and “aah” at its (temporarily) emerald green tinge. But how do officials turn the water green?

First, a bit of history: The dyeing tradition became an annual thing nearly 60 years ago, in 1962, but its real origins go back even further. In the early days of his administration as Mayor of Chicago, Richard J. Daley was a man on a mission to develop the city’s riverfront area. There was just one problem: The river itself was a sewage-filled eyesore. In order to get to the bottom of the city’s pollution problem and pinpoint the exact places where waste was being discarded into the waterway (and by whom), Daley authorized the pouring of a special green dye into the river that would allow them to see exactly where dumping was occurring.

Fast-forward to late 1961 when Stephen Bailey—part of the Chicago Journeymen Plumbers Local, the city’s St. Patrick’s Day Parade chairman, and a childhood friend of Daley’s—witnessed a colleague’s green-soaked coveralls following a day of pouring Daley’s dye into the Chicago River. That gave Bailey an idea: If they could streak the Chicago River green, why not turn it all green?

Three months later, revelers got their first look at an Ecto Cooler-colored river when the city poured 100 pounds of the chemical into the water. They got a really good look, too, as the river remained green for an entire week.

Over the next several years, the same practice was repeated, and again it was carried out by the Plumbers Local. The only difference was that the amount of dye used was cut in half over the next two years until they finally arrived at the magic number: 25 pounds of dye = one day of green water.

Unfortunately, the dye that was intended to help spot pollution was an oil-based fluorescein that many environmentalists warned was actually damaging the river even more. After fierce lobbying, eco-minded heads prevailed, and in 1966 the parade organizers began using a powdered, vegetable-based dye.

While the exact formula for the orange powder (yes, it's orange until it's mixed with water) is kept top-secret—in 2003 one of the parade organizers told a reporter that revealing the formula would be akin to “telling where the leprechaun hides its gold”—there are plenty of details that the committee lets even non-leprechauns in on.

The dyeing process will begin at 9 a.m. on the morning of the parade, Saturday, March 17 (it's always held on a Saturday) when six members of the local Plumbers Union hop aboard two boats, four of them on the larger vessel, the remaining two on a smaller boat.

The larger boat heads out onto the water first, with three members of the crew using flour sifters to spread the dye into the river. The smaller boat follows closely behind in order to help disperse the substance. (The best place to catch a glimpse is from the east side of the bridge at Michigan Avenue, or on Upper and Lower Wacker Drive between Columbus and Lake Shore Drives.)

Approximately 45 minutes later, voila, the Chicago River is green—but don’t expect it to stay that way. These days, the color only sticks around for about five hours. Which is roughly the same amount of time it takes to get a perfectly poured pint of Guinness if you venture out to an Irish pub on St. Patrick’s Day.

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