Mott T. Greene traces the history of geology in nineteenth-century Europe and America in a clear and comprehensive introduction to the geological thought of the period. Greene asserts that the standard accounts of nineteenth-century geology, which dwell on the work of Anglo-American scientists, have obscured the important contributions of continental geologists; he balances this traditional emphasis with a close study of the innovations of the French, German, Austro-Hungarian, and Swiss geologists whose comprehensive theory of earth history actually dominated geological thought of the time. Based largely on original sources, Greene's account demonstrates that scientific interest in the late nineteenth century shifted from uniform and steady processes to periodic and cyclic events. He also puts continental drift theory in its context, showing that it was not a revolutionary idea but one that emerged naturally from the European geologists' study of the origin of mountains, oceans, and continents.