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."