96 



XXVIII 



and now 11^ feet above 



the ocean. Mr. Freyer also, wlio resided some years in 

 South America, has confirmed these statements ; ^ and Mr. 

 Darwin obtained evidence that the remains of an ancient 

 wall, formerly washed by the sea, 



high-water mark, acquired several feet of this elevation 

 during the earthquake of 1822. f 



The shocks continued up to the end of September 1823 • 

 even then, 48 hours seldom passed without one, and some- 

 times two or three were felt during 24 hours. Mrs. Graham 

 observed, after the earthquake of 1822, that besides a beach 

 newly raised above high-water mark, there were several older 

 elevated lines of beach, one above the other, consisting of 

 shingle mixed with shells extending in a parallel direction to 

 the shore, to the height of 50 feet above the sea. J 



Extent of country elevated. — By some observers it has been 

 supposed that the whole country from the foot of the Andes 

 to a great distance under the sea was upraised in 1822, the 

 greatest rise being at the distance of about 2 miles from the 

 shore. ' The rise upon the coast was from 2 to 4 feet: — at 

 the distance of a mile inland it must have been from 5 to 6 

 or 7 feet.' § It has also been conjectured by the same eye- 

 witnesses to the convulsion, that the area over which this 

 permanent alteration of level extended may have been equal 

 to 100,000 square miles. Although the increased fall of 

 certain watercourses may have afforded some ground for 

 this conjecture, it must be considered as very hypothetical, 

 and the estimate may have exceeded or greatly fallen short 

 of the truth. It may nevertheless be useful to reflect on the 

 enormous amount of change which this single convulsion 

 occasioned, if the extent of country moved upward really 

 amounted to 100,000 square miles, — an extent just equal to 

 half the area of France, or about five-sixths of the area of 

 Great Britain and Ireland. If we suppose the elevation to 

 have been only 3 feet on an average, it will be seen that the 

 mass of rock added to the continent of America by the move- 

 ment, or, in other words, the mass previously below the leve 



^ GeoT. Soc. Proceedings, No. xl; 

 p. 179, Feb. 1835. 



-f Proceed. Geol. Soc. vol. ii. p. 447. 40, 45. 



I Geol. Trans, vol. i. 2nd ser. p. 415. 

 Journal of Science, vol. xvii. pp- 



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