The Mystery Behind Minnesota’s Devil’s Kettle Waterfall Has Been Solved

Minnesota’s Brule River is the source of a unique phenomenon that’s been puzzling locals, tourists, and scientists alike. Flowing not too far from the northern shore of Lake Superior, the Brule hits a divide as it travels through a cluster of volcanic rock that juts out in Judge C. R. Magney State Park. Split in two by the rocky fork, the river begins flowing both east and west. To the east, a waterfall is born, cascading half the river down into a pool, where it eventually meets up with the lake. But that western fork is a whole different story.

Unlike its eastern twin, the waterfall at the other end of this fork seemingly pours into nothingness. Called the “Devil’s Kettle,” this natural, rocky void has no obvious explanation on or below the surface. People have tried to solve the case of the bottomless waterfall by dropping ping pong balls into the pothole and casting dyes in an attempt to mark the water, but none of those plans have given anyone any clue as to where all this water is going. That is until Minnesota’s Department of Natural Resources got involved.

By measuring the water volume both above and below the Kettle, two hydrologists, Heather Emerson and Jon Libbey, found the numbers at each location were nearly identical. This finding suggests that the Devil’s Kettle waterfall likely rejoins the river underground shortly after the fork.

"What we think is happening is the water is going in the kettle, and coming up pretty close to immediately downstream of the falls," Jeff Green, a hydrologist for the Minnesota Department of Natural Resources, told Minnesota Public Radio.

The volume of water was flowing 123 cubic feet per second above the falls and 121 cubic feet per second several hundred feet downstream from the Kettle. In the fall of 2017, Green and retired University of Minnesota professor Calvin Alexander are planning to pour a biodegradable dye into the Kettle to get a more accurate reading on where and how the water meets back up with the river downstream.

So will the end of the mystery also mean the end of the Kettle’s allure? For some people, perhaps, but as Green points out, “it will still be a fascinating spot, and a beautiful spot."

7 Top-Rated Portable Air Conditioners You Can Buy Right Now

Black + Decker/Amazon
Black + Decker/Amazon

The warmest months of the year are just around the corner (in the Northern Hemisphere, anyway), and things are about to get hot. To make indoor life feel a little more bearable, we’ve rounded up a list of some of the top-rated portable air conditioners you can buy online right now.

1. SereneLife 3-in-1 Portable Air Conditioner; $290

SereneLife air conditioner on Amazon.
SereneLife/Amazon

This device—currently the best-selling portable air conditioner on Amazon—is multifunctional, cooling the air while also working as a dehumidifier. Reviewers on Amazon praised this model for how easy it is to set up, but cautioned that it's not meant for large spaces. According to the manufacturer, it's designed to cool down rooms up to 225 square feet, and the most positive reviews came from people using it in their bedroom.

Buy it: Amazon

2. Black + Decker 14,000 BTU Portable Air Conditioner and Heater; $417

Black + Decker portable air conditioner
Black+Decker/Amazon

Black + Decker estimates that this combination portable air conditioner and heater can accommodate rooms up to 350 square feet, and it even comes with a convenient timer so you never have to worry about forgetting to turn it off before you leave the house. The setup is easy—the attached exhaust hose fits into most standard windows, and everything you need for installation is included. This model sits around four stars on Amazon, and it was also picked by Wirecutter as one of the best values on the market.

Buy it: Amazon

3. Mikikin Portable Air Conditioner Fan; $45

Desk air conditioner on Amazon
Mikikin/Amazon

This miniature portable conditioner, which is Amazon's top-selling new portable air conditioner release, is perfect to put on a desk or end table as you work or watch TV during those sweltering dog days. It's currently at a four-star rating on Amazon, and reviewers recommend filling the water tank with a combination of cool water and ice cubes for the best experience.

Buy it: Amazon

4. Juscool Portable Air Conditioner Fan; $56

Juscool portable air conditioner.
Juscool/Amazon

This tiny air conditioner fan, which touts a 4.6-star rating, is unique because it plugs in with a USB cable, so you can hook it up to a laptop or a wall outlet converter to try out any of its three fan speeds. This won't chill a living room, but it does fit on a nightstand or desk to help cool you down in stuffy rooms or makeshift home offices that weren't designed with summer in mind.

Buy it: Amazon

5. SHINCO 8000 BTU Portable Air Conditioner; $320

Shinco portable air conditioner
SHINCO/Amazon

This four-star-rated portable air conditioner is meant for rooms of up to 200 square feet, so think of it for a home office or bedroom. It has two fan speeds, and the included air filter can be rinsed out quickly underneath a faucet. There's also a remote control that lets you adjust the temperature from across the room. This is another one where you'll need a window nearby, but the installation kit and instructions are all included so you won't have to sweat too much over setting it up.

Buy it: Amazon

6. Honeywell MN Series Portable Air Conditioner and Dehumidifier; $400

Honeywell air conditioner on Walmart.
Honeywell/Walmart

Like the other units on this list, Honeywell's portable air conditioner also acts as a dehumidifier or a standard fan when you just want some air to circulate. You can cool a 350-square-foot room with this four-star model, and there are four wheels at the bottom that make moving it from place to place even easier. This one is available on Amazon, too, but Walmart has the lowest price right now.

Buy it: Walmart

7. LG 14,000 BTU Portable Air Conditioner; $699

LG Portable Air Conditioner.
LG/Home Depot

This one won't come cheap, but it packs the acclaim to back it up. It topped Wirecutter's list of best portable air conditioners and currently has a 4.5-star rating on Home Depot's website, with many of the reviews praising how quiet it is while it's running. It's one of the only models you'll find compatible with Alexa and Google Assistant, and it can cool rooms up to 500 square feet. There's also the built-in timer, so you can program it to go on and off whenever you want.

Buy it: Home Depot

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13 Facts About Robert E. Peary, North Pole Explorer

Christie's, Wikimedia Commons // Public Domain
Christie's, Wikimedia Commons // Public Domain

Robert Edwin Peary, called "one of the greatest of all explorers," claimed to have been the first person to reach the North Pole on April 6, 1909. But from the moment his achievement was announced to the world, Peary was mired in a controversy that overshadowed his other accomplishments as a skilled civil engineer, natural historian, and expedition leader. Here are a few things you should know about this daring Arctic adventurer.

1. Robert Peary was extremely close to his mother.

Robert Edwin Peary was born May 6, 1856, in Cresson, Pennsylvania, an industrial town in the Allegheny Mountains. His father died when he was 3, and his mother, Mary Wiley Peary, returned with her son to her home state of Maine. As an only child, Peary formed a close bond with his mother, and when he attended Bowdoin College in Brunswick, Maine, they lived together in rooms off campus. When Peary married Josephine Diebitsch, Mary accompanied the couple on their honeymoon on the Jersey Shore and then moved in with the newlyweds, to Josephine's utter surprise. The explorer confided all of his aspirations to his mother throughout his life. In one prophetic letter to her following his first expedition to Greenland in 1886, he wrote:

"I will next winter be one of the foremost in the highest circles in the capital, and make powerful friends with whom I can shape my future instead of letting it come as it will ... remember, mother, I must have fame, and I cannot reconcile myself to years of commonplace drudgery and a name late in life when I see an opportunity to gain it now."

2. Robert Peary had a side hustle as a taxidermist.

Peary enjoyed a childhood spent outdoors playing sports and studying natural history. After graduating from college with a degree in civil engineering, Peary moved to his mother's hometown of Fryeburg, Maine, to work as a county surveyor. But the county had little need for a surveyor, and to supplement his income, he taxidermied birds. He charged $1.50 for a robin and $1.75 to $2.25 for ducks and hawks.

3. Before he went to the North Pole, Robert Peary went to Nicaragua.

Portrait of Robert Peary
Robert Peary in his naval uniform
The American Museum Journal, Wikimedia Commons // No Known Copyright Restrictions

In 1881, Peary was commissioned by the Navy Civil Engineer Corps, which made him a naval officer with a rank equivalent to lieutenant. Three years later, renowned civil engineer Aniceto Menocal picked Peary to lead a field party to survey an area in Nicaragua for a canal linking the Pacific and Atlantic oceans. Peary's ability to hack through thick jungle and scale mountains impressed Menocal enough that he hired Peary for a second survey of Nicaragua in 1887, this time with a well-funded, 200-person operation.

4. Robert Peary met Matthew Henson in a Washington, D.C. hat shop.

Though some details of the encounter differ, Peary met his eventual polar partner Matthew Henson at B.H. Stinemetz & Son, a hatter and furrier at 1237 Pennsylvania Avenue. Peary needed a sun helmet for his second trip to Nicaragua. He also needed to hire a valet. The shop's owner recommended his clerk, Henson, who surely impressed Peary with his years of experience on ships. Henson accompanied Peary to Nicaragua and on every Arctic expedition thereafter, including the successful North Pole excursion in 1908-1909.

5. Robert Peary made seven trips to the Arctic.

Peary's first trip to Greenland occurred in 1886 between his two trips to Central America. With a Danish companion, he trekked 100 miles across the Greenland ice cap but had to turn back when food ran low.

During his second and third expeditions (1891-1892 and 1893-1895), Peary, Henson, and company traversed the northern end of the ice cap and established that Greenland's land did not extend to the North Pole. On his fourth trip (1896-1897) [PDF], he brought back meteorites for the American Museum of Natural History. Peary's fifth and sixth expeditions (1898-1902 and 1905-1906) tested a feasible route to the North Pole and established relationships with Inughuit communities on which Peary would rely for assistance and supplies. Peary and Henson finally reached the North Pole on the seventh expedition in 1908-1909.

6. Robert Peary's successes in Greenland contrasted with two previous polar disasters.

Robert Peary in furs
Robert Peary, in fur clothing, stands on the deck of the Roosevelt.
Library of Congress // No Known Restrictions on Publication

In 1879, newspaper mogul James Gordon Bennett and Navy commander George Washington DeLong organized an expedition to reach the North Pole via the Bering Strait in a reinforced ship, the Jeannette. After months of besetment, ice crushed the ship and the crew made a desperate escape to Siberia, where all but two members died. Then, Army lieutenant Adolphus Greely led a 25-member magnetic survey expedition to the Canadian high Arctic in 1881. Relief ships failed to reach them for three years. By the time rescue arrived and they returned home, only Greely and five other men had survived starvation. The public's appetite for polar adventure waned until, a few years later, Peary's triumphs in Greenland earned him a heroic reputation and revived interest the quest for the North Pole. 

7. Robert Peary lost eight toes to frostbite.

On the grueling march to establish his camp at Greely's abandoned Fort Conger on the 1898-1902 expedition, Peary suffered a severe case of frostbitten feet. When they reached the hut, Henson took off Peary's footwear and revealed marble-like flesh up to his knees. As Henson removed the commander's socks, eight of Peary's toes popped off with them. As Bradley Robinson writes in the Henson biography Dark Companion, Peary reportedly said, "a few toes aren't much to give to achieve the Pole."

8. Robert Peary's wife Josephine accompanied him to the Arctic when she was eight months pregnant.

Josephine Diebitsch Peary was a formidable adventurer as well [PDF]. Her father Hermann Diebitsch, a Prussian military leader who had immigrated to Washington, D.C., directed the Smithsonian Institution's exchange system. Josephine worked at the Smithsonian as a clerk before marrying Peary in 1888. Bucking social convention, she insisted on accompanying his second expedition in 1891-1892, and in Greenland she managed the day-to-day operation of the base camp, including rationing provisions, bartering goods, hunting, and sewing furs. She even helped defend the men from a walrus attack by reloading their rifles as fast as they shot them.

She also went on Peary's third Greenland trip when she was eight months pregnant, and gave birth to their daughter Marie Anighito—dubbed the Snow Baby by newspapers—at their camp. In total, Josephine went to Greenland multiple times, wrote three bestselling books, gave lecture tours, was an honorary member of the American Alpine Club and other organizations, and decorated the family's apartment with narwhal tusks, polar bear skins, fur rugs, and other polar trophies.

9. Matthew Henson saved Robert Peary from a charging musk ox.

Cigarette card featuring explorer Matthew A. Henson
A cigarette card for the American Tobacco Company's Hassan Cork Tip cigarettes shows a portrait of Matthew Henson in a fur parka. The card belongs to the "World's Greatest Explorers" series.
American Tobacco Company, Library of Congress // No Known Restrictions on Publication

In 1895, Peary and Henson scouted a route toward the Pole over the northern edge of Greenland’s ice cap, just as they had done on their previous trip in 1891-1892. They reached a promontory called Navy Cliff, in extreme northeastern Greenland, but could go no farther. On the way back to their camp on the northwestern coast, they suffered from exhaustion, exposure, and hunger. Their only chance to make it back to camp was to find game.

As described in Dark Companion, Peary and Henson stumbled upon a herd of musk oxen. Henson and Peary killed several, but in his weakened state, Peary shot and missed one. The animal turned around and charged Peary. Henson picked up his gun and pulled the trigger. "Behind [Peary] came the muffled thud of a heavy, fallen thing, like a speeding rock landing in a thick cushion of snow," Bradley Robinson writes in Dark Companion. "Ten feet away lay a heap of brown, shaggy hair half sunken in a snowdrift."

10. Robert Peary absconded with a 30-ton meteorite.

In 1818, explorer John Ross wrote about several meteorites near Greenland's Cape York that served as the Inughuit's only source of metal for tools. In 1896, Peary appropriated the three huge meteorites from their territory. (By the late 19th century, Inughuit had obtained tools via trade and no longer needed the stones for that purpose.) The largest of the three weighed 30 tons and required heavy-duty equipment to load it onto Peary's ship without capsizing the vessel. 

Josephine Peary sold the meteorites to the American Museum of Natural History for $40,000 (nearly $1.2 million in today's money). They remain on display in the museum's Hall of Meteorites, where custom-built supports for the heaviest one extend into the bedrock of Manhattan island.

11. Theodore Roosevelt was one of Robert Peary's biggest supporters.

Robert Peary and Theodore Roosevelt
President Theodore Roosevelt (left) greets Robert Peary on the deck of the S.S. Roosevelt on July 7, 1908. Peary stopped at TR's home in Oyster Bay, New York, before departing on his North Pole quest.
George Borup, American Geographical Society Library, University of Wisconsin-Milwaukee Libraries // Public Domain

Peary and President Theodore Roosevelt shared a dedication to the strenuous life, and TR—who had served as the assistant secretary of the Navy—helped Peary obtain his multi-year leaves of absence from civil engineering work. "It seems to me that Peary has done valuable work as an Arctic explorer and can do additional work which entitles him to be given every chance by this Government to do such work," Roosevelt wrote to Secretary of the Navy William H. Moody in 1903. Peary repaid the favors by naming his custom-built steamship the S.S. Roosevelt.

In 1906, TR presented the explorer with the National Geographic Society's highest honor, the Hubbard Medal, for Peary's attainment of farthest north. Roosevelt also contributed the introduction to Peary's book about his successful quest for the North Pole.

12. Robert Peary met his nemesis, Frederick Cook, more than a decade before their feud.

Frederick Cook, a New York City physician, signed up as the surgeon for Peary's second trip to Greenland in 1891-1892. Neither Peary nor Matthew Henson was very impressed with his wilderness skills. Afterwards, Cook joined an expedition to Antarctica and claimed he summited Denali in Alaska, though his climbing partners disputed that feat.

So when Peary and Henson arrived back in Greenland in September 1909 after attaining the North Pole on April 6, they were shocked to hear that Cook had supposedly reached the Pole in spring 1908 and had announced it to the world just five days before Peary had returned to civilization. "[Cook] has not been at the Pole on April 21st, 1908, or at any other time," Peary told newspapers. "He has simply handed the public a gold brick."

From then on, Peary and his family strenuously defended his claim to the Pole. Cook had left his journals and instruments in Greenland in his dash to announce his discovery to the world, and Peary refused to transport them aboard his ship to New York, so it became Cook's word against Peary's. Peary also had the backing of wealthy funders, The New York Times, and the National Geographic Society, who eventually decided the matter in Peary's favor. But the controversy never went away; as late as 2009, the centennial of Peary's claim, historians and explorers were reexamining Peary's records and finding discrepancies in the distances he traveled each day on his way to the Pole. Cook's journals were lost in Greenland, and he spent time in jail for mail fraud. The jury is still out.

13. Robert Peary advocated for a Department of Aeronautics.

Peary was an early proponent of aviation for exploration as well as military defense. As World War I engulfed Europe, he argued for the creation of an air service, the Department of Aeronautics, that would operate alongside the Army and Navy and could then be used for lifesaving coastal patrol. Peary embarked on a 20-city tour to drum up public support for the Aerial Coastal Patrol Fund and raised $250,000 to build stations along the U.S. coast.

The Navy later implemented many of Peary's suggestions, but the tour left the explorer in frail health. He was diagnosed with incurable pernicious anemia and died on February 20, 1920. He was buried in Arlington National Cemetery, and his gravesite is adorned with a large granite globe inscribed with a motto in Latin, Inveniam viam aut faciam—"I shall find a way or make one."

Additional sources: Dark Companion, The Arctic Grail: The Quest for the Northwest Passage and the North Pole