XIV PERMANENT ELEVATION OF THE LAND 331 



been overwhelmed, though so often shaken by the severest 

 shocks. From the great wave not immediately following the 

 earthquake, but sometimes after the interval of even half an 

 hour, and from distant islands being affected similarly with the 

 coasts near the focus of the disturbance, it appears that the 

 wave first rises in the offing ; and as this is of general occur- 

 rence, the cause must be general : I suspect we must look to 

 the line where the less disturbed waters of the deep ocean join 

 the water nearer the coast, which has partaken of the move- 

 ments of the land, as the place where the great wave is first 

 generated ; it would also appear that the wave is larger or 

 smaller, according to the extent of shoal water which has been 

 agitated together with the bottom on which it rested. 



The most remarkable effect of this earthquake was the 

 permanent elevation of the land ; it would probably be far 

 more correct to speak of it as the cause. There can be no doubt 

 that the land round the Bay of Concepcion was upraised two 

 or three feet ; but it deserves notice, that owing to the wave 

 having obliterated the old lines of tidal action on the sloping 

 sandy shores, I could discover no evidence of this fact, except 

 in the united testimony of the inhabitants, that one little rocky 

 shoal, now exposed, was formerly covered with water. At the 

 island of S. Maria (about thirty miles distant) the elevation 

 was greater ; on one part, Captain Fitz Roy found beds of 

 putrid mussel-shells still adhering to the rocks, ten feet above 

 high-water mark : the inhabitants had formerly dived at low- 

 water spring-tides for these sjiells. The elevation of this 

 province is particularly interesting, from its having been the 

 theatre of several other violent earthquakes, and from the vast 

 numbers of sea-shells scattered over the land, up to a height 

 of certainly 600, and I believe, of looo feet. At Valparaiso, 

 as I have remarked, similar shells are found at the height of 

 1 300 feet : it is hardly possible to doubt that this great 

 elevation has been effected by successive small uprisings, such 

 as that which accompanied or caused the earthquake of this 

 year, and likewise by an insensibly slow rise, which is certainly 

 in progress on some parts of this coast. 



The island of Juan Fernandez, 360 miles to the N.E., was, 

 at the time of the great shock of the 20th, violently shaken, so 



