Jacques-Yves Cousteau: O CAPTAIN, MY CAPTAIN

"The best way to observe fish is to become a fish," wrote Jacques-Yves Cousteau in 1952. "And the best way to become a fish...is to don an underwater breathing device called the Aqua-Lung." Like many thousands of other humans-who-would-be-fish, I took his advice.

Captain Cousteau's legacy is renewed as each new diver slips below the surface and perpetuates the motto of his beloved ship, Calypso: "We must go and see for ourselves." Over dinner in Orlando, Fla., last January, he urged, "We must explore! The greatest threat to the oceans is ignorance. Permanent mistakes are being made by good people who do not know what they do not know about the sea."

History will recognize him as a statesman of the sea, a heroic explorer, a voice for the ocean. Some will smile, recalling his great charm, lilting French accent, red cap, irrepressible sense of wonder, passion for discovery and talent as a consummate communicator. He touched our minds and hearts, luring us onward--and downward. While celebrating a life well lived, I personally mourn the loss of a trusted friend. Surely the sea does too.

--By Sylvia A. Earle

Earle, a noted oceanographer, holds a world record for the greatest depth--3,280 ft.--ever reached by a solo untethered diver.