EARTHQUAKES. 



301 



which have been felt at frequent intervals up 

 to the time of the writing of this article. 

 The city of Charleston seems to have been 

 near the center of disturbance, although the 



It is only of recent years that any pretense 

 has beeu made of keeping a correct record of 

 every shock, and it is, therefore, almost im- 

 possible to say whether earthquakes are in- 



greater portion of South Carolina was severely creasing in frequency. The table is believed 

 shaken. The accompanying illustrations will to be the most complete yet published. 



serve as specimens of the damage done. 



Causes. Seismology, the science of earth- 



HOUSE IN LINCOLNVILLE, 8. C. CHIMNEY-BASE CRUSHED BY UPWARD MOVEMENT OF THE EARTH. 



On Aug. 10, 1884, a strong earthquake oc- quakes, is still in its infancy. Mr. Mitchill 

 curred in New England and the Middle States, says: "When engaged in the task of collecting 

 The center of intensity seems to have been at these curious and interesting phenomena, I 



Jamaica and Amity ville, on Long Island. At 

 Jamaica the walls of the Presbyterian Sunday- 

 school were cracked in two places, the open- 

 ings being from one to two inches in width 

 and extending from roof to foundation. In 

 a house at Amityville a large mirror, reaching 

 from the ceiling to the floor, was cracked from 

 top to bottom, and the walls of the room were 

 cracked in two places; a broom-handle could 

 be laid in the cracks in the wall. 



The following table has been compiled from 

 the records of Prof. Rockwell, as reported in 

 the " American Journal of Science and Arts " : 



was in expectation that physical occurrences, 

 so immediately before our eyes and under our 

 feet, would have qualified me to form some- 

 thing like a tolerable theory of earthquakes. I 

 must own, however, that, after all the infor- 

 mation I have collected, 1 have not been en- 

 abled to offer a solution by any means satis- 

 factory to myself/' Several hypotheses have 

 been invented to explain the phenomena of 

 earthquakes, and the advocates of each find 

 arguments to support those they favor, in the 

 various conditions of earth, air, water, and the 

 celestial bodies at the time of the seismic dis- 

 turbance. It has been attempted by some 

 scientists to draw distinctions between earth- 

 quakes, earth-oscillations, earth-tremors, and 

 earth-pulsations. Briefly stated, the theories 

 may be said to be six : 



1. The theological theory, held by an im- 

 mense number of people, who believe that the 

 earthquake is due to the direct intervention of 

 God, as a punishment for sin or a warning to 

 righteousness. This theory is of the greatest 

 antiquity. 



2. The mechanical theory, which imputes 

 the earthquake to the slipping of rock strata, 

 and lays especial stress upon the earth's falling 



