Read Everest - The First Ascent: How a Champion of Science Helped to Conquer the Mountain Online
Authors: Harriet Tuckey
Food supplies proved less of a problem than Pugh had feared. Their basic provisions included freeze-dried meat and vegetables, tinned foods, butter, chocolate, and cheese, which they kept cool in ice caves. In the autumn they had fresh mutton and yak meat, and fruit and vegetables brought up by local people. In the winter, fresh vegetables were occasionally flown in from Kathmandu after Hillary arranged for the winter party to build the Swiss Red Cross a makeshift airstrip at Mingbo. The Red Cross was in the area to help Tibetan refugees from Chinese Communist rule.
By December 28, Pugh, in full control and with his team settled in and working well together, had summed up progress in a letter to Josephine: “I am in full control here and am doing my best to keep everyone happy. So far everything is going smoothly and reasonably efficiently. Ed . . . has done everything possible to be helpful since we had that row in November, but I am afraid I shall never really trust him again. I don’t think he ever really understood what a scientific expedition involves.”
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Winter in the Silver Hut
One day toward the end of January, a strange man walked into base camp at Mingbo. A small, slight figure, he was wearing a red turban, a short black jacket, cotton trousers, and a shirt, and he was barefoot in spite of the cold and the snow. The man asked if he could stay for a month, promising he wouldn’t need much food—only a small amount of meat and a little milk. Pugh was not prepared to allow him to remain since he had no warm clothing, sleeping bag, or shoes, and the temperatures at night were often as low as 14° Fahrenheit. Giving him a bar of dried meat and offering him some money, he told the man to go down and spend the night at the expedition’s camp at Changmatang, where it would be warmer.
But the man refused to leave, instead turning his face westward and beginning to pray volubly. Surprisingly he was still at Mingbo the next morning, having spent the night in the Sherpas’ hut. They had tried to make him go away, but he refused, telling them that they could kill him if they chose. The Sherpas suspected him of being a Chinese spy, one pointing to a bullet scar on the man’s hand and some khaki clothing in his scant bundle. They were implacable that he could not remain at the camp, so in the end he left, but instead of going down he set off uphill toward the Mingbo Glacier. The next day he was seen by some of the Sherpas, wandering barefoot in the snow near the Green Hut. Still refusing to go down, he told them he had spent the night sheltering under a rock.
Three days later a violent snowstorm developed. The temperature inside the laboratory tent dipped below 14°F. That night, Pugh, lying in his warm sleeping bag listening to the harsh wind outside, felt so guilty that he couldn’t sleep. At first light, fearing the man was already dead, he took two Sherpas, rushed up onto the glacier, and began a frantic search. After a miserable and fruitless day they returned to Mingbo only to find the man sitting by the cookhouse, looking perfectly healthy, having survived for several days on the glacier without food and only such water as he could get from eating snow. At night he had slept in the lee of a rock covered by his meager overcoat, yet he had no trace of frostbite. This astonishing feat of endurance entirely changed everyone’s attitude toward him. The Sherpas recognized him as a holy pilgrim, and Pugh, seizing a research opportunity, agreed to let the man stay for two weeks on condition that he participate in some physiological tests.
Pugh was fascinated. His previous research had suggested that people were better able to survive exposure to cold if they were fat, yet this man was very thin. He turned out to be a Nepalese carpenter named Man Badhur, from a village a few valleys away. Blessed with a religious revelation the year before, he had been living ever since on a simple diet of fruit, raw meat, milk, and tea, until, only four weeks past, a second religious revelation had brought him to the Mingbo Valley on the present pilgrimage.
Pugh carried out a battery of experiments to find out how he survived the cold. He consumed only about 600 calories per day but had a curious habit of eating glass, showing a marked preference for microscope slides and pipettes, and eventually had to be restrained from devouring their precious supplies.
The tests did not reveal any magical ability to tolerate cold but rather what Pugh described as “an exceptionally fine adjustment of normal physiological processes” as compared with the “coarse” responses of most people. Exposed to intense cold, a person’s usual reaction is a fivefold rise in metabolism, with violent bouts of shivering as the body tries to warm itself. Blood retreats to the trunk to protect the vital organs, predisposing the bloodless hands and feet to frostbite. Man Badhur’s metabolism, however, increased only half as much as a normal person’s, albeit enough to keep his body at a sustainable temperature, and his blood did not retreat from his extremities. This much more apt response to cold allowed him to sleep comfortably without the temperatures of his hands and feet falling to dangerous levels.
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Pugh’s study of Man Badhur was an interesting diversion from the main research program, which had set out to establish the highest altitude to which people could become fully acclimatized, and to investigate how altitude affects the body over an extended period. The Silver Hut was only about 4,000 feet higher than the base camp at Mingbo, but the impact of this relatively small increase in altitude proved far greater than expected. Most of the young scientists adapted easily to the altitude at Mingbo, but all were “challenged” by living in the Silver Hut, where the pressure of oxygen in the air was about half what it is at sea level. They had to descend from time to time to recuperate. John West described what it felt like:
You are constantly aware of shortness of breath, and even a small effort such as sitting up in the bunk at night left you panting for breath for a couple of minutes. There was a marked loss of initiative so that it was always difficult to start new projects. Memory was poor and people made a lot of arithmetical and other errors. We found that we could carry out experiments if the protocol was clearly defined, especially if there was a checklist, but problem solving when there was an unexpected situation was slow and difficult.
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Everyone at the Silver Hut found their appetite was poor and they lost weight and muscle bulk relentlessly—at a rate of between 1 and 3 pounds a week. For that reason alone they probably could not have remained there indefinitely. Minor infections and injuries such as cuts were slow to heal. In the early days they suffered bouts of uneven breathing at night. West later wrote that it was like “having some sort of chronic, grumbling disease; nothing is really working as well as it should.”
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No one had spent such long periods at high altitude before, and Pugh was acutely aware of the risk of his men suffering permanent damage. He was particularly concerned that they should not stay high without breaks for longer than was good for them, simply out of bravado. “The object is to produce the best results,” he insisted, “not wear ourselves out by trying to exceed our tolerance.”
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An important safety measure was the “generous supply of oxygen” they took with them “for the treatment of sickness and for rescue operations in case of accident.”
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The young scientists were well aware that if they went down to Mingbo, their mood and their appetite would improve and their weight would increase, but they were always keen to remain up at the Silver Hut, which was very comfortable compared with Mingbo. Also, as West and Jim Milledge both admitted, there was an element of competitive pressure not to go down.
Some coped better than others. Mike Gill, the youngest team member, felt he achieved a “sort of equilibrium” after a while. But Pugh and Lahiri both had difficulty all through the expedition, frequently having to leave the Silver Hut and retire down to the Green Hut for a rest. Even the expedition puppy, Rakpa, became listless and stopped growing. Nevertheless, the Silver Hut was continuously occupied from December 17 until the end of April the following year. All the members of the winter party spent at least 70 days at 19,000 feet, and two, Milledge and Gill, were at that height for 110 days.
Much of the research was devoted to exploring the impact of altitude on the oxygen transport system—the mechanisms by which oxygen is absorbed from the atmosphere and carried to the tissues. Continuing the work Pugh had begun on Cho Oyu and Everest, an important part of the program was devoted to measuring the body’s responses to varying levels of exercise at high altitude.
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The old exercise tests, done by stepping on and off boxes and running up measured tracks, were replaced by two specially designed stationary bicycles—one at Mingbo and one at the Silver Hut—which Pugh had adapted from racing bicycles. To measure maximum exercise capability, the men took turns pedaling in time to the inexorable ticking of a metronome. While they pedaled, a brake was gradually applied to the wheel, making them feel as if they were cycling up an ever-steeper hill, until at the end they were totally exhausted and blue from lack of oxygen. Pugh was never happy unless they reached the point of virtual collapse and “practically fell off [the bicycle] semi-conscious.”
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In the final minutes of the test the cyclist breathed through a mouthpiece which delivered his exhaled breath into a Douglas bag. This enabled breathing rates to be measured and samples of breath to be analyzed with the precious Haldane gas analyzers. The tests confirmed what Pugh had found on Everest: that even when they were fully acclimatized, the men’s maximum work output at 19,000 feet was only about half what it was at sea level.
The scientists wanted to find out whether the same applied to Sherpas, but the Sherpas had never seen a bicycle before, and only Da Tenzing had the coordination to ride one (or was the only Sherpa foolish enough to admit he could handle it). The tests revealed that Da Tenzing’s maximum capacity for exercise had declined far less than that of the sea-level scientists, suggesting that Sherpas, as might be expected, were better adapted to altitude. This was confirmed in many practical ways: The Sherpas regularly carried 60-pound loads up to the Silver Hut at the same speed as the acclimatized lowlanders could climb without loads. The comparisons broke new ground. It had not yet been recognized, for example, that athletes brought up at high altitude have superior oxygen-transport systems, which give them a built-in advantage over lowlanders in long-distance running.
On top of the tubes, mouthpieces, and Douglas bags, the stationary cyclist had a great many other devices and probes to put up with. He would have an oximeter attached to his ear, measuring the concentration of oxygen in his arterial blood. An electrocardiogram recorded the behavior of his heart. Blood samples were taken from a vein in the hand so the carbon dioxide and oxygen levels could be analyzed and the chemical changes in the blood charted. His blood pressure was taken, electrodes attached to his head measured brain activity, thermometers measured temperature, pulses were taken, and so on.
Benchmark data gathered at sea level was used for comparison. Data like this had never been obtained from men who were exceptionally well acclimatized, and Pugh hoped to go further, taking a stationary bicycle up onto Makalu to make the highest-ever observations.
The bicycle tests revealed that levels of oxygen in the subjects’ arterial blood fell sharply with exercise. At sea level the arterial blood is usually around 95 percent saturated with oxygen, but even at rest in the Silver Hut, it averaged only about 67 percent. On the bicycle, however, as the cyclists neared exhaustion, the level occasionally dropped as low as 50 percent—below the level at which an unacclimatized person might lose consciousness. By comparison the cyclists only felt extremely breathless.
One of the factors that determines the level of oxygen in the arterial blood is how easily oxygen transfers from the lungs into the blood. John West studied the process to find whether, with acclimatization, changes occur in the lungs to allow oxygen to transfer more efficiently through the lung walls into the blood. He used a method which entailed giving his subjects small quantities of carbon monoxide to inhale to see how much they absorbed.
When he began analyzing their exhaled breath, however, he found to his horror that they were breathing out more carbon monoxide than he was giving them. This led to the discovery that they were all suffering from carbon monoxide poisoning from the fumes of the Primus stoves used for cooking in the hut. After that, all the cooking was done outside and everyone in the hut felt noticeably better.
The problem sorted out, West was able to establish that the lungs did not become more efficient with acclimatization. Under “conditions of extreme oxygen deprivation,” he later wrote, “the lungs just do not have time to properly oxygenate the blood as it flows through them.”
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This was a groundbreaking discovery.
The shortage of oxygen at high altitude causes people to breathe faster than they do at sea level. Many also suffer bouts of uneven breathing at night. Breathing is regulated with the help of sensors in the body which respond to the levels of carbon dioxide and oxygen in the blood. Jim Milledge studied how this system is affected by altitude and acclimatization. Sukhamay Lahiri studied the gases in the blood. Pugh focused on the increases in red blood cells, and the impact of oxygen deprivation on the function of the heart. Mike Ward explored the effects of altitude on the kidneys and the endocrine glands. Mike Gill investigated the impact of oxygen deprivation on the senses, such as hearing and sight, and the mental functions of the brain, such as concentration and memory.
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His psychometric tests, which included tasks like card sorting, were specially designed to avoid “invidious” comparisons between the highly competitive scientists in the hut who minded a great deal about their intellectual prowess.