The Great Revolution in the Earth Sciences in the Mid-Twentieth Century Henry R. Frankel . The Continental Drift Controversy . 4 volumes. Volume 1: Wegener and the Early Debate . xxii + 604 pp., illus., bibl., index. Volume 2: Paleomagnetism and Confirmation of Drift . xviii + 525 pp., illus., bibl., index. Volume 3: Introduction of Seafloor Spreading . xvi + 476 pp., illus., bibl., index. Volume 4: Evolution into Plate Tectonics . xix + 675 pp., illus., bibl., index. Cambridge: Cambridge University Press, 2012. $400 (cloth).