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What Are Those Picturesque Dutch Windmills Actually For?

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When most of us think of a windmill, we think of the quaint Dutch variety, which are so emblematic of Holland that the 19-windmill complex in the village of Kinderdijk has been named a UNESCO World Heritage Site. Those towering windmills with their lattice-shaped blades, widespread since before the days of Don Quixote (finished in 1615), weren’t keeping the lights on, like today’s wind farms. So what did they do?

In the windy Netherlands, those quaint structures were an important part of flood control beginning in the 15th century. A quarter of the country lies below sea level, which makes it incredibly prone to flooding. The Dutch have refined their flood control systems over hundreds of years, and their engineering is so effective that other countries, like the U.S., are now trying to adopt their techniques as climate change puts more cities at risk of flooding.

Windmills harnessed the power of wind to pump water out of what are called polders, swampy areas reclaimed from the water and turned into arable farmland. Windmills pumped the water out of the low-lying ground to prevent flooding and keep crops from drowning [PDF]. They could draw water up almost five feet, where it would be stored before being drained into rivers or back into the sea. If water needed to be raised more than five feet, mills were installed in a series, called a molengang, so that the first mill would lift the water five feet, then a second higher mill would lift another five feet, and so on until it could drain into a canal.

According to a translated 1962 history of Dutch windmills by windmill preservationist Frederick Stokhuyzen, there were about 9000 windmills in Holland in the 1800s, and the earliest mentions of Dutch windmills date back to the 13th century. Before polders were established, windmills—as the word itself might lead you to believe—were already places to grind grain and mustard seeds. Wind power was also used to cut timber, make paper, and press oil—essentially, anything that needed to be pounded, shredded, or mixed. Aesthetically, these windmills looked much the same from the outside, though their interior machinery and layout were different.

The interior of a tower mill. Image Credit: Frederick Stokhuyzen via University of Groningen

In larger windmills, including drainage mills, the miller tended to live on the lower floors of his workplace, much like a lighthouse keeper would.

Author Peter Moore discusses the life of a miller in his history of weather forecasting, The Weather Experiment: The Pioneers Who Sought to See the Future, noting that working at a wind-powered mill required serious skill.

“The art of windmilling is almost completely lost today but in [the 1800s] it was a common practice that required mental alertness,” Moore wrote. The miller “would have worked inside, operating the gearing system, rotating the sails and applying the brake when the wind blew too strongly. This was a real danger.”

He continued:

"If the sails were not furled in a storm its arms could spin around at an ever-quickening pace, propelled by its own force as well as by that of the wind. The friction of the movement had been known to set mills alight, as had attempts to belatedly jam the brake wheel. The miller, therefore, had to be attuned to coming weather, judging the subtle shifts in the cloud base, the dimming of the ambient light or the quickening of the breeze."

“Harbor with Windmill” by Jan van Vlaardingen Couver via Wikimedia Commons // Public Domain

Dutch windmills also served as messengers. Millers broadcast news—including whether the mill was open for business—by adjusting the position of the windmill’s sails. Tilting the sails to look like a lopsided “X” could indicate joy or mourning, depending on where the sails were located in relation to the vertical. If the top sail was a little before the vertical, that indicated joy (for births, weddings, etc.); if it was just past the vertical, that meant mourning (for funeral processions). During World War II, resistance forces used windmill blades to spread information about Nazi raids.

Windmills were so integral to life in the Netherlands that they are ubiquitous in Dutch landscape paintings. Certainly they’re more picturesque than the American mills that powered textile production and other industries in the 19th century, though they may not have had the same mass production abilities.

However, windmills no longer play the vital role in industrial production in the Netherlands, nor are they the most effective form of flood control anymore. There are only about 1200 left, many of them in the western region of Holland, though the whole country still celebrates them on the second Saturday and Sunday of May for National Mill Day.

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Big Questions
How Long Could a Person Survive With an Unlimited Supply of Water, But No Food at All?
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How long could a person survive if he had unlimited supply of water, but no food at all?

Richard Lee Fulgham:

I happen to know the answer because I have studied starvation, its course, and its utility in committing a painless suicide. (No, I’m not suicidal.)

A healthy human being can live approximately 45 to 65 days without food of any kind, so long as he or she keeps hydrated.

You could survive without any severe symptoms [for] about 30 to 35 days, but after that you would probably experience skin rashes, diarrhea, and of course substantial weight loss.

The body—as you must know—begins eating itself, beginning with adipose tissue (i.e. fat) and next the muscle tissue.

Google Mahatma Gandhi, who starved himself almost to death during 14 voluntary hunger strikes to bring attention to India’s independence movement.

Strangely, there is much evidence that starvation is a painless way to die. In fact, you experience a wonderful euphoria when the body realizes it is about to die. Whether this is a divine gift or merely secretions of the brain is not known.

Of course, the picture is not so pretty for all reports. Some victims of starvation have experienced extreme irritability, unbearably itchy skin rashes, unceasing diarrhea, painful swallowing, and edema.

In most cases, death comes when the organs begin to shut down after six to nine weeks. Usually the heart simply stops.

(Here is a detailed medical report of the longest known fast: 382 days.)

This post originally appeared on Quora. Click here to view.

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Big Questions
Why is Friday the 13th Considered Unlucky?
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Today, people around the globe will feel uneasy about getting out of bed, leaving their homes, or going about their normal daily routines, all because of a superstition. These unfortunate folks suffer from “paraskavedekatriaphobia,” a common neurosis familiar to us all: the fear of Friday the 13th. But just where did this superstitious association come from, and how did it catch on?

The truth is that no one is absolutely sure where the idea that Friday the 13th is unlucky originated. Donald Dossey, the founder of the Stress Management Center and Phobia Institute in Asheville, North Carolina, suspects the fear can be traced back to a Norse myth about 12 gods who had a dinner at Valhalla—the fabled hall where legendary Norse heroes feasted for eternity after they died—that was interrupted by a 13th guest, the evil and mischievous god Loki. According to legend, Loki tricked Höðr (the blind god of winter and son of Odin, the supreme god in Norse mythology) into shooting his brother Baldr (the benevolent god of summer who was also a son of Odin) with a magical spear tipped with mistletoe—the only substance that could defeat him. Thus the number 13 was branded as unlucky because of the ominous period of mourning following the loss of such powerful gods by this unwanted 13th guest.

For whatever reason, among many cultures, the number 12 emerged throughout history as a "complete" number: There are 12 months in a year, 12 signs of the zodiac, 12 Gods of Olympus, 12 sons of Odin, 12 labors of Hercules, 12 Jyotirlingas or Hindu shrines where Shiva is worshipped, 12 successors of Muhammad in Shia Islam, and 12 tribes of Israel. In Christianity, Jesus was betrayed by one of his 12 Apostles—Judas—who was the 13th guest to arrive for the Last Supper. Surpassing the number 12 ostensibly unbalances the ideal nature of things; because it is seen as irregular and disrespectful of a sense of perfection, the number 13 bears the stigma of misfortune and bad luck we know today.


Friday joins in the mix mostly because all of the early accounts of Jesus’s crucifixion agree that it took place on Friday—the standard day for crucifixions in Rome. As Chaucer noted in The Canterbury Tales, "And on a Friday fell all this mischance." Yet perpetuating Friday as an unlucky day in America came from the late 19th-century American tradition of holding all executions on Fridays; Friday the 13th became the unluckiest of days simply because it combined two distinct superstitions into one. According to the Oxford University Press Dictionary of Superstitions, the first reference to Friday the 13th itself wasn’t until 1913. (So despite actually occurring on Friday, October 13, 1307, the popular notion that the Friday the 13th stigma comes from the date on which the famed order of the Knights Templar were wiped out by King Philip of France is just a coincidence.)

The repercussions of these phobias reverberated through American culture, particularly in the 20th century. Most skyscrapers and hotels lack a 13th floor, which specifically comes from the tendency in the early 1900s for buildings in New York City to omit the unlucky number (though the Empire State Building has a 13th floor). Street addresses sometimes skip from 12 to 14, while airports may skip the 13th gate. Allegedly, the popular Friday the 13th films were so-named just to cash in on this menacing date recognition, not because the filmmakers actually believed the date to be unlucky.

So, is Friday the 13th actually unlucky? Despite centuries of superstitious behavior, it largely seems like psychological mumbo jumbo. (One 1993 study seemed to reveal that, statistically speaking, Friday the 13th is unlucky, but the study's authors told LiveScience that though the data was accurate, "the paper was just a bit of fun and not to be taken seriously." Other studies have shown no correlation between things like increased accidents or injuries and Friday the 13th.)

And Friday the 13th isn't a big deal in other cultures, which have their own unlucky days: Greeks and Spanish-speaking countries consider Tuesday the 13th to be the unluckiest day, while Italians steer clear of Friday the 17th. So today, try to rest a little easy—Friday the 13th may not be so unlucky after all.

Additional Source: 13: The Story of the World’s Most Popular Superstition.

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