Science: Deepest Diver

When Senior Commissioned Boatswain George Wookey of the British navy went over the side of the experimental diving ship H.M.S. Reclaim, he knew he was headed for a trying experience. The Reclaim was anchored in a cold Norwegian fiord, and on the bottom, at 600 ft. below the surface, was a steel table. Boatswain Wookey’s job was to descend to the table in an ordinary diving suit and stay there for a specified time. If he accomplished this and survived, he would break the diving record by a wide margin.

Men in the rigid, strong-walled cabin of a bathyscaphe (diving ship) have descended 13,300 ft. to the bottom of the ocean, and such diving is physically easy. The pressure they feel remains about the same throughout the dive. But when a man goes to the bottom in a flexible diving suit (as he must if he wants to do any work there), he is not sheltered from the pressure of the water, which increases about one pound per square inch for every two feet of descent. The air that he breathes, pumped into his helmet through a tube from the surface, must have pressure enough to keep the water out. Such pressure is not kind to frail human flesh.

Boatswain Wookey, a ruddy, biggish man, made his dive in standard diving equipment (a rubberized fabric suit with a round helmet), but behind him stood the calculations of many scientists who had scheduled every minute and foot of the dive. A crew of engineers and pathologists helped him into the water or watched instruments in the hold of the Reclaim.

Helium for Dizziness. The main trouble with deep diving is that when the diver breathes ordinary air under too much pressure, nitrogen dissolves in his blood and tissues, causing dizziness and other kinds of trouble. Below about 240 ft., the air pumped down to the diver is replaced by a mixture of oxygen and helium. The helium penetrates the tissues, but does not have the bad effects of nitrogen. When the diver comes to the surface, however, he must be decompressed slowly lest bubbles of helium give him painful, sometimes fatal “bends.”

When Boatswain Wookey was lowered into the water, he was breathing ordinary air, but when he reached 40 ft., the pump began supplying a mixture of oxygen (8.5 parts) and helium (91.5 parts). Going down was comparatively easy. In spite of the 273 Ibs. of pressure on every square inch of his body (39,312 Ibs. per sq. ft.), he felt fine. “I felt no more effect from the helium,” he says, “than I would from nitrogen at shallow depth. My mind was clear. I did the job I was sent down to do.” His token job, to prove that he could do useful work, was to unbolt a wire.

Narrow Margin. The scientists on board the Reclaim had figured on his staying at 600 ft. for exactly three minutes. Wookey stayed two minutes longer to untangle his air tube. This threw the dive off schedule and threatened Wookey’s narrow margin of safety. As his shipmates began to haul him up, a sudden chill struck through him. “It was the most intense cold,” he said, “that I ever felt. That cold gets into your guts, and you feel you can’t stand it.”

Slowly, with many stops, he rose toward a submerged decompression chamber that hung 220 ft. below the surface. It was open at the bottom, with compressed air keeping the water out. Inside waited Able Seaman George Clucas, an expert diver, to give Wookey aid and comfort while he finished the long decompression process.

When Wookey reached the chamber, he waited ten minutes while the pressure in his helmet was reduced to the pressure in the chamber (about 110 Ibs. per sq. in.). Then he climbed into the chamber itself, and Clucas took the front glass off his helmet. “He was so cold,” said Clucas. “So very cold. He could hardly stand up when he reached me.” The two men sat down for a long, dull, eight-hour wait, supplied with candy, hot coffee, reading matter and rum.

Foot by foot the decompression chamber was hoisted toward the surface. Pound by pound its air pressure fell. As it neared the surface, Clucas closed the bottom door to hold the remaining pressure, and the chamber with the two men inside was taken on board the Reclaim. For an hour they breathed pure oxygen to flush residual helium and nitrogen out of their systems. Then the door was opened, and they stepped out. At once they felt the dreaded pains of the bends, Wookey in his shoulders, Clucas in his legs and chest. They ran into a larger decompression chamber, where they were kept under oxygen for four more hours. When they came out, they felt fine, but tired and very hungry.

Wookey had beaten the diving record by 65 ft. and he had done potentially useful work at 600 ft. He could have attached a cable to a sunken submarine at that depth. Some day he expects to go deeper; the limit, he feels, is imposed by cold and the long time needed for proper decompression. Asked why a man will do such a thing, Wookey says, “I think diving is intensely interesting, especially in shallow water. I go deeper because it’s my job.”