Deep

by James Nestor

  The condition became known as caisson disease or, more commonly, the bends, named for the excruciating pain that the afflicted workers felt in their knees and elbows. Scientists later discovered that the shift from pressurized air in the caissons to normal air at the surface was causing nitrogen gas to bubble in the workers’ bodies and collect in their joints.

  It would take another forty years for engineers to understand that it wasn’t the deep water that was harming the ocean explorers—it was the deep-diving machines. Ironically, while Western divers in carefully constructed suits or caissons were drowning or getting their faces sucked off or suffering the bends at depths above sixty feet, two thousand miles to the south, Persian pearl divers were regularly plummeting to twice that depth and doing it with nothing more than a knife and a single breath of air. They suffered none of these maladies, and they had been diving to these depths for thousands of years.

  Eventually, Western engineers developed elaborate systems to protect the body from underwater forces. They figured out how pressures change at depth and how oxygen can become toxic. Lethbridge’s and Deane’s primitive inventions eventually led to armored suits with compressed air, submarines, and scuba-diving decompression tables.

  In 1960, Don Walsh, a U.S. Navy lieutenant, and Jacques Piccard, a Swiss engineer, took a steel chamber called Trieste down to 35,797 feet in the Pacific Ocean’s Marianas Trench—the bottom of the deepest sea. Two years later, humans were living underwater.

  The first underwater habitat, built by Jacques Cousteau, was set up thirty-three feet below the ocean’s surface in an area off the coast of Marseilles. Called Conshelf, it was about as big as the cabin of a Volkswagen bus, and just as cold and wet. “The hazards are great and exceed the challenges,” said Cousteau of Conshelf. In fact, the hazards were so great that Cousteau sent two underlings in his place. They lasted a week.

  A year later Cousteau planted a more deluxe five-room model—with living room, shower, and sleeping quarters—on the seafloor off the coast of Sudan. Footage from the expedition, later featured in Cousteau’s Oscar-winning documentary A World Without Sun, shows a kind of futuristic/French paradise where by day, aquanauts spent their time floating through Technicolor sea gardens, and by night, they smoked, drank wine, ate perfectly prepared French meals, and watched television. The aquanauts lasted a month. Their only complaint was the lack of women down there to “keep us company.”*

  By the late 1960s, more than fifty undersea habitats around the world were being built, and many more were planned. Australia, Japan, Germany, Canada, and Italy were all going deep. Cousteau predicted that future generations of humans would be born in underwater villages and “[adapt] to the environment so that no surgery will be necessary to permit them to live and breathe in water. It is then that we will have created the man-fish.” The race for inner space, it appeared, was on.

  And then it was off. After just a few years, all but a handful of the habitats were scrapped. Living underwater proved to be much more of a challenge, and far more expensive, than anyone had thought. Salt water ate away at metal structures; storms ripped foundations from the seafloor; aquanauts lived in constant fear of decompression sickness and infections.

  This was the space age, after all; men were landing on the moon and building houses in orbit, so spending weeks underwater in a cold, wet box—in an environment you couldn’t even see in, let alone be seen in—seemed pointless. And few land dwellers could relate to the research on microbiology and oxygen toxicity that was being conducted down there. Scientists had proved that humans could dive down to the deepest ocean floors and live underwater, but so what?

  TODAY, ALMOST ALL OCEAN research is done topside via robots dropped from the decks of boats. Humans know more about the ocean’s chemical composition, temperatures, and topography, but they have also grown more physically and spiritually distanced from it.

  Most marine researchers (at least, the ones I interviewed early on) never even get wet. Aquarius, one of the last oceanic institutions where researchers got wet and stayed wet for ten days at a time, was slated for closure.

  I wanted to see it, this last piece of the institutional legacy of ocean exploration, before it joined the trash heap of inventions rusting away on the ocean floor. I wanted to see how the sanctioned experts researched the ocean before I headed out to spend a year with the renegades.

  KEY LARGO, SEVEN MILES OUT, in hissing and storming seas. I am about to attempt my first scuba dive down sixty feet to Aquarius. I flash the captain of the motorboat that shuttled me here a thumbs-up, adjust the mouthpiece, and head down. I descend twenty, thirty, forty feet and notice a stream of bubbles belching from the seafloor, like an upside-down waterfall. An Aquarius safety diver stands wreathed in the bubbles, beckoning me closer. I kick toward him, duck my head, and, a few seconds later, reemerge in the air of the wet deck at the back of Aquarius.

  “Please take off your wetsuit,” says a man at the top of the metal staircase. He hands me a towel to put around my waist. “And welcome to Aquarius.”

  His name is Brad Peadro and he’ll be leading my tour. Because even the tiniest puddle can take days or weeks to dry in Aquarius, all visitors are required to leave their scuba gear and wet clothes at the door. Clad in my towel, I follow Peadro through the deck and into a control room. The squawk of amplified voices from the PA and blasts of pressurized air echo against the steel walls. A few paces in, I see two men and two women sitting arm to arm around a kitchen table. They are marine biology graduate students from the University of North Carolina, Wilmington, and they’re just finishing up a ten-day mission researching sponges and coral. Between them lies a flattened, half-empty bag of Oreos. “The long days do wear on you,” says a pallid man named Stephen McMurray who is researching the population dynamics of sponges. He dips a spoon into a Styrofoam cup of instant noodles and looks through a window to the seafloor below.

  “Nothing is ever dry down here,” says John Hanmer, sitting across from him. “Ever.” Hanmer, who is studying parrotfish, laughs and looks at his hands. Another aquanaut, Inga Conti-Jerpe, sits beside him. Her matted, frizzy hair clings to her scalp like wet plaster. “The pressure does interesting things to your skin,” she says with a chuckle.

  The aquanauts all laugh, then fall silent. They laugh again, then go silent again. I can’t help but feel that everyone down here is a little off. Not in the cabin-fever kind of way that I expected; they are far too jolly for that. They seem, basically, drunk.

  I learn that having your body pressurized to 36 psi for extended lengths of time can produce mild delirium. At higher pressures, more nitrogen dissolves in the bloodstream, eventually producing the same effect as nitrous oxide, or laughing gas. The more nitrogen in the bloodstream, the more whacked out the aquanauts feel. By the end of a ten-day mission, the whole group is on the equivalent of a Whip-It bender.

  Lindsey Deignan, the aquanaut I watched apply ointment to her knee from Mission Control the night before, looks especially dazed. “The longer we’re down here, the larger the space seems,” she says, smiling broadly. “It’s now like triple the size. It’s as big as a school bus! But it seems bigger than that!”

  To me, the aquanauts’ euphoric haze feels like an essential coping strategy in this dank, cramped, dangerous place. Moldy towels, rusting metal, and suffocating humidity are the main facts of life here. And you can’t just get up and go home without having blood squirt out your eyes. To make matters worse, every thirty seconds or so, the crests and troughs of the waves at the surface shift the pressure inside Aquarius, requiring all of us to equalize our sinus cavities by popping our ears.

  The tour continues. Peadro leads me three paces east, into the sleeping quarters—two rows of bunk beds stacked three high—and then back into the kitchen. The tour is over, he says. There’s nothing else to see on Aquarius.

  I noticed that we haven’t seen a bathroom, and I ask Brad if we’ve passed it.

  “We usually just go out the back the
re,” he says, pointing to the wet deck entrance I just swam through. The front door of Aquarius doubles as its outhouse.

  Toilets are notoriously difficult to manage in underwater habitats, mostly due to the constant shifts in air pressure, which can create vacuums inside the plumbing lines. In early underwater habitats, toilets would explode and splatter waste throughout the compartment. Aquarius’s commode is an improvement, but it is so small and offers so little privacy that aquanauts prefer to do their business in the water out back. Even that has its problems. Sea life fights for the human “food.” On one occasion, a male aquanaut who was submerged in the wet deck from the waist down had his ass bloodied by a hungry fish.

  Peadro tells me to head back to the wet deck. At 36 psi, nitrogen usually takes ninety minutes to reach dangerous levels, but it can sometimes happen sooner; to be safe, Aquarius allows visitors a maximum of a half hour onboard. My time here is up.

  I put on my wetsuit, splash through the door, and kick into the smoky blue water. The constant gurgle from my scuba regulator scares off everything around me; it’s like I’ve gone bird watching with a leaf blower strapped to my back. And the wetsuit, tank, and knot of tubes around my body prevent me from even feeling the seawater.

  Being inside Aquarius was the same way. Even though the habitat allows the aquanauts to do invaluable long-term research, sitting in that steel tube and looking at the ocean through windows and video screens was, to me, hopelessly isolating. I’ve felt far more connected to the ocean and its inhabitants surfing on its surface than sitting in a rubber-and-steel tube six stories beneath it.

  BACK ON THE MOTORBOAT, I strip off my scuba gear and sit in the captain’s cabin. Before I can leave, members of the Aquarius support crew need to dive down some canisters of food and supplies for the aquanauts.

  The captain, an intense, sunburned man named Otto Rutten who has been working at Aquarius for more than twenty years, hands me a bottle of water. He tells me about some close calls he’s had in this job—rescues in the high seas, explosions, emergency ascents.

  “It was really the Wild West out here,” he says. “I mean, we weren’t even using scuba for a lot of the deliveries.” He explains that scuba took too long and enabled him to make only a few dives at a time before the nitrogen gas in his bloodstream built up to dangerous levels. So instead, Rutten and the other crew members would just jump into bathing suits, put on fins and masks, and freedive the supplies down.

  Swimming down there while carrying a bulky, airtight container and then coming back would take well over a minute. I mention to Rutten that he and the other divers must have stopped down at Aquarius to take a breath before returning to the surface. Rutten laughs and says that if he had, the high-pressure air would have probably killed him.

  It was by stripping off all the gear—the tanks, weights, regulators, and buoyancy-control devices—that Rutten and his coworkers could dive deeper, more often, and four times as fast as someone wrapped in the most technologically advanced equipment.

  I ask Rutten if he had any kind of special training to freedive to such depths.

  “No, not really,” he says. “It’s easy. You just take a breath and go.”

  −300

  IN 1949, A STOCKY ITALIAN air force lieutenant named Raimondo Bucher decided to try a potentially deadly stunt in a lake on the island of Capri. Bucher would sail out to the center of the lake, take a breath, and go down one hundred feet to the bottom. Waiting there would be a man in a diving suit. Bucher would hand the diver a package, then kick back up to the surface. If he completed the dive, he’d win a fifty-thousand-lira bet; if he didn’t, he would drown.

  Scientists warned Bucher that, according to Boyle’s law, the dive would kill him. Formulated in the 1660s by the Anglo-Irish physicist Robert Boyle, this equation predicted the behavior of gases at various pressures, and it indicated that the pressure at a hundred feet would shrink Bucher’s lungs to the point of collapse. He dove anyway, delivered the package, and returned to the surface smiling, with his lungs perfectly intact. He won the bet, but more important, he proved all the experts wrong. Boyle’s law, which science had taken as gospel for three centuries, appeared to fall apart underwater.

  Bucher’s dive resonated with a long line of experiments—most of them very cruel and even monstrous by modern standards—that seemed to indicate that water might have life-lengthening effects on humans and other animals.

  This line of inquiry arguably began in 1894, when Charles Richet rounded up several ducks and tied strings around their necks. He took half the group, tightened the strings until the birds couldn’t breathe, then timed how long it took them to die. He then repeated the process with the other half, but these he strangled underwater. The ducks left in the open air lived only seven minutes, while the ducks kept underwater survived up to twenty-three. This was very odd. Both groups were deprived of oxygen in the same way, but the ducks put underwater lived three times longer.

  Richet, who would eventually win a Nobel Prize for his work on the causes of allergic reactions, thought water might be affecting the ducks’ vagus nerve. In both humans and ducks, this nerve extends from the brain stem to the chest and can slow the heart rate. Richet theorized that a slower heart rate would result in decreased use of oxygen and thus longer survival times.

  He tested this theory by injecting one group of ducks with the drug atropine, which keeps the vagus nerve from slowing the heart rate. He left the second group untouched and atropine-free. He strangled both groups and timed how long it took them to die. They all died in about six minutes.

  Then, with another group of ducks, he injected atropine and repeated his experiment, this time with the ducks underwater. The atropine-dosed ducks took more than twelve minutes to die underwater—twice as long as the ducks in open air. Even though the vagus nerve had been blocked with atropine and could not slow the heart rate, the water still had some inexplicable life-lengthening effect on the ducks. Richet took one atropine-drugged duck out of the water after twelve minutes, untied its neck, and resuscitated it. It lived.

  Lung size, blood volume, and even the vagus nerve couldn’t explain Richet’s results. Water alone was extending their lives. He wondered if it had the same effect on humans.

  In 1962, Per Scholander, a Swedish-born researcher working in the United States, confirmed that it did. He gathered a team of volunteers, covered them with electrodes to measure their heart rates, and poked them with needles to draw blood. Scholander had seen the biological functions of Weddell seals reverse in deep water; the seals, he wrote, actually seemed to gain oxygen the longer and deeper they dove. Scholander wondered if water could trigger this effect in humans.

  He started the experiment by leading volunteers into an enormous water tank and monitoring their heart rates as they dove down to the bottom of the tank. Just as it had done with ducks, water triggered an immediate decrease in heart rate.

  Next, Scholander told the volunteers to hold their breath, dive down, strap themselves into an array of fitness equipment submerged at the bottom of the tank, and do a short, vigorous workout. In all cases, no matter how hard the volunteers exercised, their heart rates still plummeted.

  This discovery was as important as it was surprising. On land, exercise greatly increases heart rate. The volunteers’ slower heart rates meant that they used less oxygen and therefore could stay underwater longer. This also explained, to some degree, why Bucher and those ill-fated ducks could survive up to three times longer in water than they could in open air: water had some powerful capacity to slow animals’ hearts.

  Scholander noticed something else: Once his volunteers were underwater, the blood in their bodies began flooding away from their limbs and toward their vital organs. He’d seen the same thing happen in deep-diving seals decades earlier; by shunting blood away from less important areas of the body, the seals were able to keep organs like the brain and heart oxygenated longer, extending the amount of time they could stay submerged. Immersion in wat
er triggered the same mechanism in humans.

  This shunting is called peripheral vasoconstriction, and it explains how Bucher could dive to below one hundred feet without suffering the lung-crushing effects that Boyle’s law had predicted. At such depths, blood actually penetrated the cell walls of the organs to counteract the external pressure. When a diver descends to three hundred feet—a depth frequently reached by modern freedivers—vessels in the lungs engorge with blood, preventing them from collapse. And the deeper we dive, the stronger the peripheral vasoconstriction becomes.

  Boyle’s law seemed not merely bent in the face of this physiological conversion; it was nullified.

  Scholander found that a person need submerge only his face in water to activate these life-lengthening (and lifesaving) reflexes. Other researchers tried sticking a hand or a leg in the water in an attempt to trigger the reflex, but to no avail. One researcher even put volunteers into a compression chamber to see if pressure alone would trigger a similar diving reflex. No dice. Only water could trigger these reflexes, and the water had to be cooler than the surrounding air.

  As it turns out, the tradition of splashing cold water on your face to refresh yourself isn’t just an empty ritual; it provokes a physical change within us.

  Scholander had documented one of the most extreme transformations ever discovered in the human body, a change that occurred only in water. He called it the Master Switch of Life.

  Today, competitive freedivers are using the Master Switch to dive deeper and stay underwater longer than even modern scientists believe is possible.