On the floor of the Red Sea, 45 feet below the surface near Port Sudan, the seven inhabitants of an underwater village celebrated last week the end of a full month beneath the waves. For the village's mayor, Jacques-Yves Cousteau, 53, co-inventor of the Aqua-Lung that made modern skindiving possible, it was a double-barreled occasion. Down on the bottom, he celebrated his 26th wedding anniversary, and his wife Simone dropped in with a cake in a waterproof container.
The houses of Cousteau's underwater village are strong-walled steel chambers, roughly cylindrical. One of...