The Last Voyage of Somebody the Sailor

by John Barth. Little, Brown,$21.95. One can imagine that Mr. Barth’s first notion here was a question: What would Sinbad and his contemporaries at the court of Haroun alRashid have made of the equipment and misadventures of a modern yachtsman? On that keel Mr. Barth has built a Walloping Windowblind of a novel that lurches from present to past, from New Jersey to Serendib, from ornate erotica to bloody piracy, seldom making much sense but never quite falling into the doldrums. The novel’s complicated construction and its elaborate prose imply serious purpose, but none emerges in all its 573 pages.