EARTH Q UAKES. 183 



CHILE. 



while the Pampas, covered by thistles, clover and grass, have 

 been formed by the ancient estuary mud of the Plata. 



EARTHQUAKES. 



THIS day (Febuary 20, 1835) has been memorable, in the 

 annals of Valdivia, for the most severe earthquake experi- 

 enced by the oldest inhabitant. I happened to be on shore, 

 and was lying down in the wood to rest myself. It came 

 on suddenly, and lasted two minutes, but the time appeared 

 much longer. The rocking of the ground was very sensible. 

 There was no difficulty in standing upright, but the motion 

 made me almost giddy; it was something like the move- 

 ment of a vessel in a cross-ripple, or still more like that felt 

 by a person skating over thin ice, which bends under the 

 weight of his body. 



A bad earthquake at once destroys our oldest associa- 

 tions : the earth, the very emblem of solidity, has moved be- 

 neath our feet like a thin crust over a fluid ; one second of 

 time has created in the mind a strange idea of insecurity 

 which hours of reflection would not have produced. In the 

 forest, as a breeze moved the trees, I felt only the earth trem- 

 ble, but saw no other effect. Captain Fitz Roy and some 

 officers were at the town during the shock, and there the 

 scene was more striking ; for although the houses, from being 

 built of wood, did not fall, they were violently shaken, and 

 the boards creaked and rattled together. The people rushed 

 out-of-doors in the greatest alarm. The tides were very cu- 

 riously affected. The great shock took place at the time of 



