The catalogue for an unprecedented exhibition opening in June 1996 at the Whitney Museum of American Art, Perpetual Mirage is the first fully illustrated history of the desert West and the first full-scale study of one of the most distinctive American publishing traditions - the photographic book. Since the mid-19th century, photographs of the American Southwest - its towering mountains, majestic canyons, and unusual wildlife - have been presented to the public primarily in books.

These photographic books enabled the images to speak directly to the viewer.

In the hands of the early photographic pioneers, the photograph functioned as a tool of scientific exploration, promoted commercial (and political) development of the West, and educated and thrilled people who would never visit the exotic and remote sites captured by the camera. In later years, the masterful photographs of artists such as Ansel Adams contributed to the definition of photography as an independent artistic medium.

Even more important, these landscape photographers helped raise public consciousness about the region's fragility and its essential role in a vital, interlocking ecosystem.

The photographic legacy of the American Southwest includes the magnificent survey albums of the mid-19th century, through which most Americans first saw the region's exotic plants, ancient cliff dwellings, and natural wonders; turn-of-the-century ethnographic reports, most notably, The North American Indian project of Edward S.

Curtis; illustrated travel guides such as those by Edward Weston; books by Ansel Adams and Eliot Porter, which marshaled the environmental movement; and the photo-text documents of Dorothea Lange.