n July of 1852, a 32-year-old novelist named Herman Melville had high hopes for his new novel, Moby-Dick; or, The Whale, despite the book’s mixed reviews and tepid sales. That month he took a steamer to Nantucket for his first visit to the Massachusetts island, home port of his novel’s mythic protagonist, Captain Ahab, and his ship, the Pequod. Like a tourist, Melville met local dignitaries, dined out and took in the sights of the village he had previously only imagined. And on his last day on Nantucket he met the broken-down 60-year-old man who had captained the Essex, the...