A vulcanologist off on a seismological holiday, Tazieff sped to Chili in 1960 as soon as the earth stopped quaking. A strip of coast 18 miles by 300 miles (about from Philadelphia to Boston) had sunk 6 feet in 10 seconds. ""...Behind this desolation lay some unknown and awful dimension -- awful in the primary meaning of the word, and intensely exciting."" Strangely enough, the main body of information came from eye witnesses who reported three tidal waves, one 26 feet high moving inland at 100 miles per hour. This indicated that the quake's epicenter was in the ocean. The author discusses the earth's quake belts and seismographic instruments and gives a general history of quakes. His manner is distinguished, not too technical and he is quite adept at conveying the relative terror and magnitude of each quake. Geology and geologists get very little attention in general trade books and this one is particularly good.