Masterpieces of Science 



It is not difficult, however, tc detect in the 

 operations of nature counterbalancing forces 

 which are capable of upheaving the deposits that 

 have been formed on the sea- bottom, and of 

 piling up fresh stores of solid matter upon the 

 surface of the earth. Among these elevatory 

 and therefore reparative agents, the most impor- 

 tant place must be assigned to those which give 

 rise to earthquakes and volcanoes. After the 

 occurrence of an earthquake it is by no means 

 uncommon to find that the level of the land has 

 been shifted. Sometimes, it is true, the surface 

 is depressed, but more commonly the movement 

 is in the direction of elevation. 



Perhaps the best recorded example of such 

 upheaval is that which was observed by Admiral 

 Fitzroy and Mr. Darwin when examining the 

 western coast of South America. This region 

 is peculiarly subject to subterranean disturb- 

 ances, and in 1835 a violent earthquake, which 

 destroyed several towns, was felt along the coast 

 of Chile, extending from Copiapo to Chiloe. It 

 was found, after the shock, that the land in the 

 Bay of Concepcion had been elevated to the 

 extent of four or five feet. At an island called 

 Santa Maria, about twenty-five miles south-west 

 of Concepcion, the upheaval was easily meas- 

 ured, vertically, on the steep cliffs; and the 

 measurements showed that the south-western 

 part of the island was raised eight feet, while 

 the northern end was lifted more than ten feet 

 high. Beds of dead mussels were, in fact, hoisted 

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