National Geographic : 1952 Oct
( National Geogralhic Society 439 Ektachrome by Jacques-Yves Cousteau A Man-made Lung Gives This Diver an Hour's Permit to Explore the Twilight Sea At 132 feet below the surface, atmospheric pressure on the body is 73.5 pounds to a square inch-five times as much as at sea level. But to diver Frederic Dumas, skimming past coral branches in his Aqualung, pressure is no problem. From the tanks strapped to his back, compressed air flows by tube to his rubber mouthpiece. Inhaled, it raises pressure within his body to that of the surrounding sea. Result: he feels no more discomfort than a fish in water or a man on the beach. Dumas served as chief diver and deputy commander of a 1952 oceanographic expedition through the Mediter ranean and Red Seas. Capt. Jacques-Yves Cousteau, French naval officer and co-inventor with Emile Gagnan of the Aqualung, headed the project. Use of the Aqualung permitted Cousteau and his men to study at leisure the life of reef and grotto down to some 200 feet. It also made possible for the first time the photographing of that life in the true colors of the deep. Flashlights of intense brilliancy illuminated the twilight zone, and specially housed cameras recorded a vivid pigmen tation never seen before even by the resident fish. Dumas, here exploring a reef half a mile off France's La Ciotat, gathers an armload of giant gorgonians (corals) for examination. Their strong pigmentation, dimmed at this depth, will stain his hands bright red. Foam-rubber diving dress insulates him from cold water.