Given the constraints that the author has chosen to impose on the subject matter, Inside the Earth: Evidence From Earthquakes is an admirable achievement. Bruce Bolt is a seismologist of international reputation and an experienced and accomplished writer. In this volume, he has produced a book that goes a long way toward achieving his principal goal, that is, to provide a book for students and nonspecialists who are curious about the physical properties of planet earth. Bolt writes in a clear and concise style and in a vein that is sufficiently relaxed so that the going is fairly easy. Yet the book is crammed with authoritative information on the earth's interior, and the material is presented in a well-organized fashion that should permit even the inexperienced reader to progress through it without great impediment or backtracking.