(YA) A ulcanologist off on a seismological holiday, Tazieff sped to Chili in 1960 as soon as the earth stopped quaking. The great quake had --two days after its major shock--set Chili's volcanoes bubbing. ""... (B)ehind this desolation lay some unknown and awful dimension-- awful in the primary meaning of the word, and intensely kciting."" He and his companions traveled over 50,000 square miles of ""primary meaning""; for instance, a strip of coast 18 miles by 300 miles (about from Philadelphia to Boston) had sunk six feet in ten seconds. ""It was beyond my imagination; and a geologist's imagination, God knows, is pretty strong."" Strangely enough, the scientists' main body of information came from eye witnesses who, under the circumstances, might seem the most unreliable source of all. They reported three tidal aves, one 26 feet high moving inland at over 100 mph. This indicated that the quake's picenter was in the ocean. The author discusses the earth's quake belts, seismographic instruments and 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 earthshake.