68 



SUBTERRANEAN FIRE BENEATH GRANITE. 



elevation to subterranean fire : for, we have a recent instance of the 

 mighty power of this agent to upheave the crust of the globe. Du- 

 ring the earthquake in Chili, in November 1 822, the whole line of 

 coast, running north and south from Valparaiso, to the distance of one 

 hundred miles, was raised above its former level, the bottom of the 

 sea was laid dry, and shells were discovered sticking to the rocks, 

 some of which were not before known in those seas. It is stated by 

 an observer, that the whole country, from the coast to the feet of the 

 Andes, and even far out to sea, was permanently raised by the earth- 

 quake : the greatest rise was about two miles from the shore. The 

 granite which forms the foundation rock was rent in parallel fissures. 

 The earthquake is estimated to have extended over an area of one 

 hundred thousand miles. The average rise of the land upon the 

 coast was from two to five feet ; at the distance of a mile from the 

 shore inland the elevation was seven feet. 



During my residence in Savoy and Switzerland in the years 1820, 

 1821, and 1822, I was desirous to ascertain whether there were any 

 vestiges of the action of the subterranean fires in the Alps. In the 

 part of the great southern chain, extending from near the source of 

 the Rhone to the Litde St. Bernard, there do not occur, in the nu- 

 merous situations which I examined, or, from which I have seen spe- 

 cimens, any minerals of a volcanic character, with the doubtful ex- 

 ception of some rocks in the valley of Saass and in the Valorsine. 



Though I could observe no indications of volcanic fire in the rocks 

 themselves, I was greatly surprised with a circumstance that, as far 

 as I know, had escaped the attention of geologists. Along the whole 

 line of Alps before mentioned, which extends for one hundred and 

 twenty miles, numerous hot springs are gushing out at the feet of the 

 primary mountains, near the junction of the lowest secondary lime- 

 stone with schistose rocks passing into mica and talcous slate. It 

 was known, that a few thermal waters existed in the Valois and in 

 Savoy, but they were regarded as isolated phaenomena, and their 

 geological position had not been attended to. Since Saussure visit- 

 ed the Alps, thermal waters have been discovered in various situa- 

 tions ; and since 1 left Savoy, another considerable warm spring has 

 been opened in the vicinity of the village of Chamouni, near the 

 foot of a glacier. 



There is, also, further reason to believe, that thermal waters would 

 be found in all the deep valleys of the Alps, near the junction of the 

 primary and secondary rocks, were they not covered by eboulements 

 under heaps of loose stones (as was the case with the warm baths in 

 the valley of Bagnes in the Bas Valois ;) or were not the tempera- 

 ture of the warm springs reduced, by admixture with torrents from 

 the glaciers. 



In vol. i. ch. 8. of my " Travels in Savoy," I have described the 

 geological position of nine of the principal known thermal waters of 

 the Alps ; their temperature varies from 94° to 126*^ Fahrenheit. 



