The famous geological research ship Glomar Challenger was a radically new instrument that revolutionized earth science in the same sense that the cyclotron revolutionized nuclear physics, and its deep-sea drilling voyages, conducted from 1968 through 1983, were some of the great scientific adventures of our time. Beginning with the vessel's first cruises, which lent support to the idea of continental drift, the Challenger played a key part in the widely publicized plate-tectonics revolution and its challenge to more conventional theories. Here the leading oceanographer and earth scientist Kenneth Hsu offers an intensely personal account of the experiences of the ship's diverse crews - the sailors, drillers, marine technicians, and scientists who braved not only the ocean's resistance to surrendering its secrets but also the difficulties of balky machinery, physical illness, close quarters, and all-too-human temperaments. But the intellectual rewards of the journeys also abounded, and Hsu is the ideal writer to convey the excitement with which he and other crew scientists pursued them. The quintessential insider, he offers biographical sketches, humorous anecdotes, background information from the history of geology, and excerpts from the ship's daily operational report - all skillfully combined with a narrative history of the ship's explorations in the Pacific, Atlantic, and Indian Oceans and the polar seas. From a description of the much-debated drilling of a \"Mohole\" that would reach a mysterious realm ten kilometers below the ocean to a summary of the seafloor evidence for a meteor's having \"murdered\" the dinosaurs, the work provides an overview of the current state of marine geologyand a source book for the history of that science.