“This isn’t a book about China,” claims author Peter Hessler about the first of his three books set far from his American upbringing. “It’s about a certain small part of China at a certain brief period in time.” And Rivertown: Two Years on the Yangtze is certainly that, though his disclaimer is among the first evidences of the clear-minded humility that is one of the book’s greatest recommendations. It is a first-person account of a young man’s two-year immersion in the life of western China, and it is many things: a wide-open window into a place and a time, a travelogue, a coming-of-age tale, and a teacher’s diary.