HISTORY OF A TSUNAMI — ROBERTS 331 



break had been — imder Mount La Perouse, 58.6° north of the Equa- 

 tor and 137.1° west of the Greenwich meridian. William Stauder, a 

 Jesuit scientist then workino; at Berkeley, plotted a position slightly 

 different — near the coast at Point Astrolabe. It cannot be said which 

 most nearly fits so deeply buried an event. The violence of the jig- 

 gles recorded on the photographic paper showed how great was the 

 energy of this quake. Standard instruments at Pasadena and Berke- 

 ley showed it to be a true giant with a magnitude of 8.0 on the energy 

 rating scale devised by Caltech scientists Beno Gutenberg and Charles 

 Richter. The highest magnitude ever observed was about 8.7 on the 

 same scale, a figure representing the greatest amount of energy, ac- 

 cording to the Japanese seismologist C. Tsuboi, that can be stored in 

 stressed rocks and released in a single quake. Tliis release of energy 

 is estimated to equal some 100,000 Hiroshima-type atomic explosions, 

 though it is of course far less concentrated in its effects. One earth- 

 quake of such top-level magnitude was that of August 15, 1950, which 

 triggered tremendous landslides in the high Himalaya of the China- 

 Burma-India border area, and ultimately produced widespread floods 

 in the Assam tea gardens. Another occurred in January 1906, in a 

 remote part of Colombia, in South America. Neither killed many 

 people, but had either area been populated, the death toll would have 

 been enormous. 



The public importance attached to an earthquake is underetandably 

 keyed to the damage and casualty rolls, rather than to its scientific 

 evaluation ; hence the great earthquakes of history are not always the 

 strongest. For instance, the Santa Barbara and Long Beach trage- 

 dies of 1925 and 1933, both scientifically minor California shocks, will 

 be remembered in company with their stronger fellows, such as the 

 1908 devastation of Messina, Italy, in which 100,000 died, and the 

 Tokyo disaster of 1923, Avhich destroyed an unbelievable 576,000 build- 

 ings in an earthquake and fire which claimed almost as many lives. 

 Such a scientific front-rank event as the 1906 Colombian shock 

 escaped public notice, and it is safe to say that the great Fairweather 

 shock, which killed five people (and would have been forever infamous 

 had it struck a large city) has passed long since from public notice. 



It will not soon be forgotten by seismologists, however, who now 

 Imow it to be am.ong the four strongest shocks in the history of North 

 America. In 1811 tlie river-bottom country about New Madrid, IMo., 

 shook and shivered, and visible waves in the gromid, like those of the 

 sea surface, startled unbelieving witnesses. Reelfoot Lake was created 

 when 30,000 square miles of the land sank, some of it as much as 15 

 feet. The motions were felt by people throughout more than 2 million 

 square miles, as far away as Boston. Seismologists say it was one of 

 the greatest in all histoiy. In 1886 the famous Charleston, S.C, quake 



