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imagine that a subterraneous undulation might pass under 

 an enormous mass of mountains such as the Chilian Andes 

 (from 1 1,000 to 23,000 feet high), which would ride unshaken, 

 while lower ground on both sides suffered; just as we see 

 a ship of the line floating apparently motionless amidst the 

 waves which agitate the little boats at its side. 



To the superficial vibration may be attributed the fall of 

 the mountain peaks in Asia and in Peru, the shivered rocks 

 at Quintero and Quinquina, and those strange rotary motions 

 referred to by Mrs. Graham, by Capt. Fitzroy, and by Mr. 

 Darwin, and of which I have seen remarkable instances at 

 Tacna in Peru, and at Lima. In the latter case, the upper 

 stone of a lofty obelisk was turned half round in 1828, in 

 a manner precisely similar to that in Calabria, of which Mr. 

 Lyell has given a drawing in his Principles of Geology. 



The great extent of land and ocean throughout which 

 volcanic and subterraneous agencies have been simultaneously 

 manifested, has compelled all philosophers who have witnessed 

 them to admit the existence at least of vast lakes of melted 

 rock and lava under ground, extending to some hundred 

 thousand of square miles. Baron Humboldt is of this opinion, 

 from the observations he made in North and South America; 

 and Mr. Darwin, who experienced the great Concepcion 

 Earthquake of 1835, makes the following remarks in his 

 journal, — " From several considerations which I have not 

 space here to enter on, and especially from the number 

 of intermediate points whence liquified matter was ejected, 

 we can scarcely avoid the conclusion, however fearful it may 

 be, that a vast lake of melted matter, of an area nearly 

 doubling in extent that of the Black Sea, is spread out 

 beneath a mere crust of solid land." 



The astonishing distances at which earthquakes have been 

 felt from the focus of greatest intensity are difficult of ex- 

 planation on any other supposition than that of internal 

 fluidity; but this is a question which involves so great a 



