By 1775, 48-year-old Captain James Cook had completed two highly successful voyages of discovery and had earned a comfortable retirement. The Admiralty gave him a plum position: an honorary post at Greenwich Hospital near London, where his only responsibility was to "keep a paternal eye on the thousand or so Navy pensioners" who lived there. He quickly became bored, however, and longed to be back on the open ocean. His restlessness was exacerbated when he learned that the Admiralty was planning an expedition to look for the fabled Northwest Passage from the Pacific side—something that had never been attempted—and had assigned his former ship, the HMS Resolution, to the task. The powers that be, too, felt that Cook was the only man who could pull off such a journey, and so manipulated him into asking for the commission (which doesn't appear to have been much of a...