In the early 1950s, the Southern Pacific Railroad no longer controls the state of California, as Frank Norris described it in "The Octopus," but in the little town of Dunsmuir it still has the power to force an injured brakeman, Frank Hiller, to return to work before he is healed, and Hiller, an angry man to begin with, passes on the fear and pressure to his wife and children. "Canyon," the story of a single summer day when Hiller disappears, is through the eyes of each of them in turn, including 10-year-old John, who fears his father but is even more frightened to see his father humiliated by a world that, just a few years after World War II, is saturated with images and memories of violence. That all around them is some of the most beautiful scenery in the state is only partial comfort. In broiling, unlovely San Bernardino, an 11-year-old girl catches polio in one of the last pre-vaccine epidemics. In a hospital full of dying children and children in iron lungs, overworked doctors and nurses fight to save her. A sympathetic nurse intuits a fact the girl is too shy and downtrodden to tell -- that for her, the hospital isn't hellish at all; that compared with the dysfunctional family of Dust Bowl migrants she comes from, including a brother who is maturing into a full-blown psychopath, it's almost like Heaven. Jessamyn Colton -- dismissively called Flucy at home -- would just as soon stay in the hospital, but once she recovers -- and she is recovering -- that won't be an option.