Arnold (Fox, p. 894, etc.) visits the Mojave Desert's Coso Range for a look at some of the US's oldest, most durable--and most enigmatic--art. It's a good choice of location, with over 100,000 examples discovered: depictions of sheep, deer, coyotes, lizards, hunting tools and scenes, human figures both plain and adorned with feathers or other regalia, and more abstract images. Arnold describes the clever methods researchers use to date the petroglyphs and deduce who made them, and why; Hewitt's large, sharp full-color photographs capture the variety of the art and communicate a sense of their arid, remote setting. More cogent--and better illustrated--than Jennifer Owings Dewey's impressionistic Stories On Stone (p. 294), this offers an intriguing glimpse into an ancient mystery.