This is another of Chicago's entertaining and intelligent cultural travel titles. In this one, Erin Hogan, director of public affairs at the Art Institute of Chicago, hits the road, alone, in her Volkswagon Jetta, to discover the great works of American land art in the deserts of Utah, Arizona, New Mexico and Texas. She takes in Robert Smithson's Spiral Jetty on the Great Salt Lake, Walter de Maria's Lightning Field in New Mexico, and half a dozen other landmark works.