One looks at the preface to see if this is one of those books geared for television enlightenment: a combination of worthy sayings and wise precepts of the Greats accompanied by showy art and science. To say this is not to demean the contents, for Schneider--a scientist at the National Center for Atmospheric Research in Boulder, Colo.--and Morton, a freelance writer, make points about ecology that are worth making, even if we have heard them before. And, in the latter part of the book, there are some novel chapters to illustrate their theme. Essentially their primordial bond is between man and nature, and their moral is the duty of human beings to be stewards on the planet. We must act not out of fear and a spirit of conquest, but out of respect and sympathy: the conservation theme writ large. Their approach is through a consideration of cycles: the large repetitive patterns perceived by thinkers and built into religion, art, and philosophy East and West. They discuss, too, the development of science: the discovery of patterns and the quest for truth and order in nature (with frequent quotes from C. P. Snow, Bronowski, and other social commentators). The fresh material at the end has to do with the cycles of growth, change, decay, and renewal that underlie life on earth: the cycles of wind and water that account for weather and climate, the cycles of nitrogen, carbon, sulfur, and phosphorus necessary for plant and animal life. Here Schneider's expertise comes to the fore in deft arguments demonstrating both the beauty of the cycles that galvanize life processes and the dangers inherent in human interventions. A twice-told tale, but Schneider and Morton tell it well--especially for an upcoming generation.