This book traces the developments of the applications of the geophysical sciences to a variety of societal needs from misty beginnings to now, with emphasis on the “golden age,” the early 1920s through the 1960s. The phrase “applied geophysics” is so often taken as synonymous with “geophysical exploration” that the broader viewpoint of this work is especially welcome. The authors certainly devoted much of their treatment to exploration geophysics, as is appropriate in view of the large commitment of human and financial resources to this endeavor and the practical importance of the results. However, they have also included interesting sketches of military applications of geophysical techniques and the important technological advances that have come from these, as well as much material on ocean science. Atmospheric and space science receives less detailed coverage.