Captain Cousteau turns his attention to marine archaeology in the Caribbean area, specifically that ""field of murderous reefs,"" the Silver Bank coral formation, which wrecked so many ships and galleons and may or may not conceal the sunken remains of the 17th century Spanish treasure-ship, Nuestra Senora de la Concepcion. Cousteau reports here on the day-to-day activities of the crew and scientists of his Calypso as they enter and probe the reef for the lost galleon. So far as is known only the 17th century American adventurer and skilled excavator, William Phips, managed to locate and plunder the wreck. But others continue to dive and delve: among the chipped pots and cannon, Cousteau discovered a very contemporary American sledgehammer and two sandal soles. Surrounded by historical round-ups of Spain's colonial shipping in the 16th and 17th centuries, and the acceleration of English, French, and Dutch activity, Cousteau's diary follows procedures, plotting, navigation and most of all the growing excitement at the prospect of uncovering the Concepcion. That the chimeric wreck was quickly renamed Decepcion is ultimately of little concern. For in spite of the extraordinary toil and bubbling frustration -- hours of boring, blasting, chipping -- ""their reward is the adventure that they lived.