The Last Dive

by Bernie Chowdhury

  At sea level, the weight of air on the body, or pressure, is one atmosphere. Because water is heavier than air, the weight of the seawater pressing on a body at a depth of just 33 feet is equivalent to an atmosphere of pressure. In the water, the weight of the air needs to be added to the weight of water, so that a depth of 33 feet is two atmospheres absolute (“absolute” means combining the weights of the air and water), 66 feet is three atmospheres absolute, and so on. Haldane experimented by placing goats first at 33 feet of depth pressure, for various periods of time, then at 66 feet of depth pressure, and then at 99 feet of depth pressure. He noticed that he could bring the goats from 33 feet directly to sea-level pressure without any ill effect, but when he brought them straight up from 66 or 99 feet, they were clearly in pain. He then tried easing the pressure on the goats one atmosphere at a time, leaving them at the lesser pressure for various times before easing the pressure again. This method worked. It allowed more time for the body to eliminate nitrogen during exhalations, and prevented excess bubbles from developing. By various adjustments to the pressure-depth profile, the times exposed to those pressures, and the time taken to ease the pressure, he could bring the goats to sea-level atmosphere without their experiencing pain. Or dying.

  Before he could test humans, Haldane had to create standardized charts that could be used by those responsible for hauling the divers back up. The charts had to be easily read and interpreted, especially since they would be used on boats, in uncertain sea conditions. He came up with a set of three charts, known as diving tables, that correlated depth, time at depth, and time taken to surface. The charts also took into account excess nitrogen that remained in the body from a previous dive. In such cases, on a subsequent dive, the diver was allowed to spend less time at depth. If a diver exceeded time at depth, Haldane included depths and times for stops to be made so that his body could release excess nitrogen before he was brought to the surface. This process is known as stage decompression.

  Haldane presented his research and charts to the Admiralty, which conducted tests using human subjects. Divers achieved record depths of 210 feet without getting bent. It was miraculous. Deeper depths could not be attempted because the maximum limit of technology had been reached: Three compressors, each hand-powered by six men, were attached to the diver’s suit and supplied him with the required air. So strenuous was the effort required of the men cranking the pumps that they had to be relieved by another crew every five minutes, lest the diver suffocate. Haldane’s dive tables were published in 1907 and were soon adopted by all of the world’s navies and commercial diving companies.

  Divers learn and relearn the history of decompression theory at every level of diving instruction, and progressing to advanced open-water diving was no exception for the Rouses. All three Rouses had taken the “Advanced Open Water” diving course in Horsham, Pennsylvania, in the spring of 1989 with Bob Burns, who had been teaching for several years and was also a dive-boat captain certified by the Coast Guard. Burns was one of the owners of the diving charter boat Dina Dee, based in Brielle on the New Jersey shore and specializing in excursions to the many offshore shipwrecks. Although Chris and Chrissy were already fully cave-certified when they took the class with Burns, the instructor was impressed with their attitude of thorough engagement. The Rouses did not act like know-it-alls, even though they had a far greater degree of knowledge than most open-water divers, including most instructors. They absorbed Burns’s lessons and then went home to read at length about the subjects touched on in class. During the following lesson, they would add significantly to the class discussions, relating what they had found in their readings. Burns, delighted to have such enthusiastic students, would later ask Chris and Chrissy to come in and give lectures to his students about the techniques, challenges, and risks of cave diving, which they were happy to do.

  One of the things the Rouses learned in their readings was that decompression is more an art than a science, and is still one of diving’s great mysteries. Even if the diver does everything correctly and follows the tables, he can still get bent. Many factors influence the diver and his probability of getting bent, including fatigue, hydration, physical condition, and underwater exertion level. In the first class any diver takes, he learns the basics of decompression theory and how to use the dive tables. Many divers have difficulty grasping the concept of the dive tables, intimidated by the grid of letters and numbers. When the Rouses took Burns’s course, Sue was still confused about the proper use of the dive tables. Her one-weekend basic class had left her feeling lost when it came to using these critical tools, so Chris and Chrissy tutored her at home between sessions of Burns’s advanced class.

  “Come on, Mom, Dad and I will show you how the tables work. They’re easy,” Chrissy urged her.

  Sue frowned. “Oh, I don’t know. It seems so complicated, with all these numbers everywhere.”

  Chris chimed in. “You gotta be kidding. You were such a whiz in school. Hey, if I can do it, you should be able to manage it in your sleep.”

  “Yeah, but I was good in languages and stuff like that. Math was never something I liked.”

  Sue appreciated the support from her two men, who pulled out various books and entertained her with the story of one of diving’s great mysteries and how it came to be at least partially solved. Sue got the hang of using the dive tables with the patient coaching of her husband and her son.

  As divers ventured deeper using the decompression tables worked out by Haldane, they noted a new problem: the debilitating narcotic effects of nitrogen in the air they breathed at depth. Some people experimented with different gas mixtures. Since nitrogen is a biologically inert gas—the body does nothing with it—it was reasoned that hydrogen, neon, or helium could be used in its place. These lighter-than-nitrogen gases would allow divers to descend far deeper before they encountered narcotic effects. However, different decompression schedules had to be used that would take into account the lighter weights of these other gases and their faster absorption and elimination from the body.

  In 1945, the Swedish engineer Arne Zetterstrom dived to 500 feet using hydrogen to replace nitrogen in his breathing mix. He died on the ascent, when inexperienced surface tenders misunderstood his instructions and raised him prematurely 130 feet above his planned decompression stop. Later, the British Royal Navy diver George Wookey successfully descended to 600 feet, a record that held until the Swiss mathematician Hannes Keller—after consulting his countryman, the renowned professor and medical doctor Albert Bühlmann—dove to 730 feet using helium gas mixtures, and then in 1962 to 1,000 feet. But the 1,000-foot dive was marred by tragedy: Owing to operational problems, a news reporter who went on the dive with Keller died, as did a support diver, although Keller himself was unscathed. These high-profile diving experiments served to fix in naysayers’ minds the fickle dangers of the deep. Surely, sport divers would not be able to succeed in these deep dives where professionals had failed?

  With all of the dangers associated with deep diving, and with economic incentive to overcome those dangers, some professionals sought another way to explore the deep. They reasoned that narcosis, toxicity, and the bends could all be avoided if a diver was encased in a protective suit that would maintain his body at surface pressure no matter what the surrounding pressure. Such a hard suit would also have the advantage of allowing the diver to ascend directly to the surface when his work was done. John Lethbridge’s 1715 diving device was a crude type of hard suit, though it exposed the diver’s arms to pressure. The first truly successful suit was made by the German firm Neufeldt & Kuhnke in 1917. It resembled a science-fiction robot. The German Navy tested the suit to a depth of 530 feet in 1924, and in 1930 the suit was used in 400 feet of water to recover over one million dollars in gold bullion from the British ocean liner Egypt. During the Second World War, the German Navy employed a number of N & K suits, which were appropriated by the Allies after the conflict ended.

  Nineteen twenty-two was a busy yea
r for armored-suit inventors in the United States. Victor Campos patented a suit reportedly tested to 600 feet, and Joseph Peress patented the first spherical-type joint, which utilized a fluid to transfer pressure and made it easier for the diver to move his arms and legs. Peress built his first suit three years later, but it was not successful. His second attempt, in 1930, resulted in a suit that could take divers as deep as 447 feet; it was later successfully tested by the British Royal Navy. Peress’s suit was modified in 1969 by a British company, whose several versions over the years culminated in the JIM suit, named after the diver who tested it, Jim Jarrett. In 1976 it was used in a dive to 905 feet under the ice in the Canadian High Arctic during an oil exploration expedition.

  Spectacular as these diving feats were, armored suits still had depth limitations, just as submarines do. Ventures too deep would result in the suit’s being crushed—along with the diver inside—like an eggshell caught in the teeth of a tightening vise. For most sport divers, the cost of an armored suit and its attendant topside support requirements put it financially out of reach. Even if a sport diver could afford an armored suit, the devices were too cumbersome, and their umbilical cables connected to the surface made them impractical for significant exploration into underwater caves. Shipwreck exploration could be done with hard suits, but excursions into an intact wreck’s interior could be accomplished only by cutting away exterior metal or using explosives to make a massive hole in the wreck’s hull.

  In spite of significant advances in hard-suit design, most divers-commercial, military, and sport—had to content themselves with using traditional diving suits that left them relatively naked against the mental and physical challenges of the deep.

  One of those divers was Glenn Butler, an American who started his commercial diving career in 1968, at the age of seventeen. He made a somewhat untraditional entrance into the world of professional diving. His father had been a diver when in the U.S. Army and worked to clear shallow waters of submerged mines in the immediate aftermath of the Second World War. When he returned to civilian life, the elder Butler started a marine salvage company. His fascination with the sea was passed on to his son, who first scuba-dived when he was seven. When he was fifteen, Glenn Butler became a certified diver, and he went on to teach classes and lead dive trips for the next three years. He loved the water and knew that his life’s work would somehow involve the sea. Butler’s father tried to help his son get commercial dive training and took him to the navy yard in Washington, D.C. Glenn took one look at the equipment the navy divers were using, turned to his father, and said, “Dad, these guys are ten years behind. I want to be on the cutting edge of diving. There’s got to be a better place for me.”

  There was. In the late sixties, the place young Glenn Butler knew was at the cutting edge of diving was a commercial diving and research company called Ocean Systems, which was owned by Union Carbide. Only seventeen years old, the six-foot-three-inch Butler used his personal contacts in the New York City diving community to wangle himself an interview at the Tarrytown, New York, research facility. When Butler arrived for his interview, down the steps of the concrete building bounded Dr. Bill Hamilton, a man with long brown hair that flowed well past his shoulders, wearing overalls and an emblem of a large, bright pink pig on his chest. Hamilton did not look at all like the fighter pilot and astronaut candidate he had once been.

  Hamilton and his boss, Dr. Heinz Schreiner, headed the diving equivalent of the Edison Laboratories and Bell Labs combined. Glenn Butler was happy to get his foot in the door; he labored as an intern, without pay, for six months before he was asked, “Would you like to work as an experimental diver?”

  Being a diver in the research facility was unlike being a diver anywhere else. For one thing, divers at the research facility went into deep-water pressure, but did not get wet. Butler’s official title was “inside investigator,” which meant that he worked inside a recompression chamber as a human guinea pig. While Hamilton and others manipulated the controls from the safety of the outside, they sent Butler to various simulated depth pressures to test new breathing gases, decompression tables, decompression theories, and the limits of human physiology. Butler and other “inside investigators” would frequently get bent when they were brought back to surface pressure. Without leaving the chamber, they would immediately be repressurized and then brought back to lower surface pressure more slowly, while Hamilton and the other researchers noted the results and modified their theories and decompression tables. During one chamber dive, Butler was sent down to 1,000 feet in eleven minutes. He wasn’t on the edge of diving—he had been plunged into its abyss. Somehow, he survived intact.

  One of the offshoots of Ocean Systems’ research was the implementation of a standard for fire safety in hyperbaric (increased pressure) chambers. Improper materials used in conjunction with pure oxygen under high pressure would result in explosions and fire. These lessons were applicable outside of the diving world, though it took the launch pad fire of Apollo 1 in 1967 and the fiery deaths of the astronauts Roger Chaffee, Gus Grissom, and Edward White to stun the world and bring the connection between diving research and space exploration into focus. Though Butler, Hamilton, Schreiner, and the others at Ocean Systems would not go into space anytime soon, they did help make space exploration safer in the aftermath of the Apollo 1 tragedy, by helping NASA to develop materials safety selection criteria for use in the space program.

  With the influx of big money for oil exploration research in the 1980s, Butler moved on to become one of commercial diving’s elite, a saturation diving supervisor and diver. He directed operations and also worked under constant depth pressure, sometimes for weeks at a time, at great depths to ensure longer working times than could be achieved by having the diver decompress after each work shift. Pressure surrounding such divers is maintained at all times, which means that they have to decompress only once, at the end of the entire job. Their bodies become saturated with inert gas because they do not decompress after each shift. Butler worked anywhere in the world he was needed: Africa, Europe’s North Sea, both sides of the North Atlantic, and the Pacific. When Butler wasn’t actually in the water, working at depths sometimes exceeding 700 feet, he was confined to a cylindrical diving bell, a pressurized habitat whose floor contained a hatch that allowed him to enter and exit. Each day, the habitat was lowered from the dive platform and Butler would exit when the habitat landed on the ocean floor. After eight hours of installing or inspecting pipelines or wellheads, Butler would wearily walk along the ocean floor, kicking up clouds of sand and mud as he went—resembling Pigpen, the cartoon character in Peanuts perennially surrounded by dust—and crawl back into the refuge of his stark, constantly moist, prisonlike home. It would then be hauled back to the surface while the pressure he had been working at was maintained. No prison on earth has ever been more remote: Butler could not leave his pressurized world for the freedom beyond the habitat’s tiny viewing port, for to do so would have meant excruciating death from the bends. His body was not the only thing saturated: His bank account swelled with bonus money. In exchange for risking his life around the clock, a saturation diver receives extra compensation, just as a soldier gets combat pay.

  Unlike a soldier, a diver in saturation is slowly being killed by pressure, the unseen enemy. The pressure gnaws away at his body, and after several years of regular work a saturation diver’s X rays may show evidence of bone necrosis: blank spaces within the normally solid hip and knee bone structure. Modern medicine has made replacement of these worn bones possible, and sometimes a saturation diver requires a hip or a knee replacement.

  Though the job was hazardous, Butler enjoyed it, in spite of the pain brought about by the occasional bout of the bends, which he estimates he suffered at least seventeen times. Butler was like a prizefighter determined to battle his foe to the end. Yet much remained unknown about the physiological risks of repeated decompression sickness.

  When I saw Butler at a dive club meeting in
1992, I mistakenly thought he was drunk when I heard his slurred speech and the difficulty he had putting sentences together. I was reminded of my childhood hero Muhammad Ali, whom I met when he was already punch-drunk. During this period, in the early nineties, Butler’s memory problems and punch-drunk syndrome of slurred speech were pronounced, and medical doctors were powerless to control them. I wondered whether there was any positive correlation between Butler’s numerous bouts with the bends and his slurred speech. Butler told me that a CT scan of his brain had revealed four dormant lesions from diving that his doctors were unable to control. “My speech is all messed up because of an aneurysm—you know, a bleed in the brain,” Butler informed me. “It might have been caused by one of my diving lesions, but doctors think it was caused by hypertension.”

  Butler made steady progress and recovered normal speech and memory by 1995, as his doctors said he would. Incredibly, by the year 2000 all but one of the lesions had healed themselves, and his aneurysm-or pressure-induced slurred speech syndrome had subsided. According to Butler, his doctors’ evaluation is that he is “as good as new and not especially prone to bleeds, as long as I keep normal blood pressure.” He is still in the diving industry as a consultant, specialty equipment manufacturer, and operator of a major hyperbaric medical facility. At forty-nine, Butler still maintains an intense, almost childlike fascination with diving.

  In 1990, the use of anything other than air for sport dives was considered radical and dangerous. There were no official classes offered for the sport diver interested in using helium breathing mixtures. The public thinks of diving into caves and shipwrecks as dangerous for good reason. Only recently, since the 1950s, has diving even become a sport. Although the invention of scuba (an acronym for self-contained underwater breathing apparatus) is credited to the Frenchmen Jacques Cousteau and Émile Gagnan, in 1942, others before them had come up with similar devices. The difference was that Cousteau and Gagnan took two pieces of equipment that had existed for quite some time—the compressed gas cylinder and the demand valve, which opens when the diver inhales, allowing him to breathe on demand—and put them together in a system that would provide air to a diver whenever he breathed in. It was a novel approach. The beauty of the Cousteau-Gagnan apparatus lay in its simplicity. After the Second World War, Cousteau continued with his diving research, raised funds, and eventually produced his famous undersea television show, The Undersea World of Jacques Cousteau, and wrote many books. One of the ways Cousteau made money was by selling his scuba apparatus, the Aqualung, to sportsmen.