After navigating the physical and political properties of the world's oceans, lakes, rivers and aquifers in his last book, Water, Canadian journalist de Villiers is back on (very) dry land in this new volume—but his writing is every bit as fertile. Co-written with Hirtle (with whom he also wrote Into Africa), the book is part travel memoir, part history lesson and part archeological dig, bringing to life the stark landscape of the earth's largest desert. The first half describes how sand dunes take shape so suddenly and travel, wavelike, so quickly; why stands of petrified forests developed; and how relatively mild shifts in the earth's ecosystem and weather patterns transformed the once-verdant grasslands of a mere 10 centuries ago into today's austere environment. The book's second half discusses the ebb and flow of great cities and civilizations along both the northern (Berber and Arab) and southern (black African) edges of the desert, as well as the Moor, Tuareg and Tubu nomads who roamed between them. It also details trade patterns and tribal groupings that have existed over many centuries and takes the reader on a contemporary camel-powered salt-trade caravan. Though this book doesn't have the political urgency or current-events hook of Water, the authors' evocative blend of reportage and concise historical overview makes it a fine read for both armchair travelers and those interested in natural history. (Sept.)
