SOME PERSONAL EXPERIENCES WITH 

 EARTHQUAKES 



By Rear Admiral L. G. Billings, U. S. Navy, Retired 



THERE is no natural phenomenon 

 more deeply interesting and yet so 

 little understood as the seismic 

 disturbances which have from earliest 

 history devasted the earth and carried 

 terror and dismay into the hearts of all 

 survivors. 



Up to 1903, it is computed by an em- 

 inent scientist, Compte de Ballore, there 

 had been 159,782 recorded earthquakes. 

 Of later years, when more accurate rec- 

 ords have been kept, they have averaged 

 about 60 per annum. There is comfort 

 to the dwellers in most of the world to 

 know that 94 per cent of recorded shocks 

 have occurred in two narrow, well-de- 

 fined belts — one called the Mediterranean, 

 with 53 per cent to its credit, and, the 

 other, the Circum-Pacific, with 41 per 

 cent — while the remainder of the world 

 has only 6 per cent, widely distributed. 



The United States has been singularly 

 free from recorded seismic disturbance, 

 perhaps the most disastrous being in 

 181 1, when a very severe shock occurred 

 in the Mississippi Valley south of the 

 Ohio, which was felt in New York in 

 one direction and in the West Indies in 

 another. This earthquake changed the 

 face of the earth. A vast extent of land 

 was sunk, lakes were formed, and even 

 the course of the Mississippi River was 

 obstructed for a time (see page 67). 



Most of the earthquakes occurring of 

 late years can hardly be classed with the 

 great ones of history, nearly all of the 

 destruction being caused by uncontrol- 

 lable fires. In the more stable zones long 

 periods may elapse between shocks, as, 

 for instance, in Kingston, Jamaica, 215 

 years intervened. 



While the Panama Canal is not situ- 

 ated in the earthquake zone proper, it has 

 experienced numerous shocks, though 

 none in historic times have been fatal. 



the; CAusis Q-p e;arthquake;s 



The cause of earthquakes and vol- 

 canoes is an elusive problem, not yet set- 



tled to the satisfaction of the scientist. 

 Tremors of the earth may be caused by 

 many things. The explosion of mines, 

 falling in of caves, slipping of rock strata, 

 and many other movements of the earth 

 may cause them ; but for the great shocks 

 which have recurred almost since the his- 

 tory of the world began we must look 

 further. 



For ages theories have been evolved, 

 and, though most of them have received 

 the earnest consideration of our modern 

 scientists, they seem to be advanced only 

 to be combated and denied ; so that, after 

 all, we must confess to the humiliating 

 fact that we know very little about the 

 cause of earthquakes. 



Though many times there seem to be 

 an intimate connection between earth- 

 quakes and volcanoes, the law regarding 

 them has not been established. Some re- 

 markable coincidences have been observed 

 in late years. The terrible cataclysm of 

 Mount Pelee, which, on May 8, 1902, al- 

 most instantly killed 30,000 inhabitants, 

 was preceded by the earthquake which 

 in January and April of the same year 

 wrecked a number of cities, in Mexico and 

 Guatemala. The distance between these 

 points is at least 2,000 miles, showing 

 how deep-seated must have been the dis- 

 turbance, if, as has been suggested, there 

 was communication between them. The 

 great San Francisco earthquake was pre- 

 ceded only two days by one of the most 

 violent eruptions of Vesuvius recorded 

 in many years. 



THK BEHAVIOR OF BOGOSLOF 



It is also a significant fact that the 

 fuming island off the coast of Alaska, 

 called Bogoslof No. 3, appeared at almost 

 the same time. A revenue cutter, visit- 

 ing this island, was astonished to see that 

 the mountain, or hill, some 400 feet high, 

 on the island, had disappeared, and in its 

 place a bay had been formed. Soundings 

 showed a depth of from 8 to 25 fathoms 

 of water. 



57 



