of pieces by one of the West’s leading conservationists. It even has a soul-stirring title, An Unspoken Hunger (144 pages. Pantheon. $20), by Terry Tempest Williams, author of the best-selling “Refuge” and naturalist-in-residence at the Utah Museum of Natural History in Salt Lake City. Brace yourself to save the planet.

Actually, brace yourself for a surprise. This is not an exercise in didacticism: these are wide-ranging pieces as varied in tone as they are in subject matter. In the opener, Williams describes a visit to Africa’s Serengeti Plain. “The anticipation of seeing rhinoceros is like crossing the threshold of a dream. The haze lifts and there they are-two rhinos, male and female, placidly eating grass with prehensile lips.” Another essay describes a visit to New York, where she is moved by a fellow naturalist who can still find great beauty in the disintegrating wetlands of Pelham Bay Park in the Bronx.

Among the best pieces is a description of a walk with her husband to count bighorn sheep. The excursion then takes a sinister turn when air force Warthogs begin dropping “mock” bombs. “Flames explode on the desert,” Williams writes, “and then columns of smoke slowly rise like black demons.” When she confronts an air force officer, he boasts that these were the same weapons used in the Persian Gulf War. In one of her most amusing pieces, Williams recounts a story about Georgia O’Keeffe told to her by the photographer Eliot Porter. One day, walking in the desert with O’Keeffe, Porter found a beautiful smooth black stone. O’Keeffe immediately asked for it, she bad to have it but he refused. Sometime later O’Keeffe came to Porter’s house; the rock was on the coffee table. fie left her alone in the room, and when he came back, the rock was gone. “The next time I saw my stone, it was a photograph in Life magazine in the palm of O’Keeffe’s hand.” This is an eloquent book, full of humor and drama, and most important-Williams’s passion for saving the land she grew up in.