New York Times science editor Sullivan's latest work is an invitation to take to the roads or the skies to glean America the Beautiful--not for eyes only, but for the deeper meaning behind the palisades and calderas, the rift valleys and checkboard plains. Indeed, this may be the first book to include an index indicating air routes between major cities and what (on a clear day) you can see from above. As for the text, Sullivan conveys the latest theories and facts of geology with his usual earnest scholarship and pedantic style. Like John McPhee, he assumes some geological literacy on the part of the reader, though he goes to greater efforts to define certain ideas and terms. He begins with reviews of the shaping of North America's east and west coasts according to the latest findings of plate tectonics, sea floor subsidence, ocean formation, and continental bumps and grinds. For the rest, the chapters are short excursions across the American landscape describing the upheavals responsible for such present-day landmarks as the Grand Canyon, baja California, and the fuel-and fossil-rich areas around Wyoming; later chapters discuss how arbitrary land divisions, industry, and suburbia have contributed their changes in America's face and figure. As one reads, it is increasingly evident that this is a book to take along: a geological Baedeker to have on hand when the tourist is on the site and can appreciate the detailed descriptions and occasional eye-witness asides that Sullivan provides. Something for sophisticated travelers, then, or perhaps a goad to armchair geologists to take a look outside.