APPENDIX. 



381 



again- The rock from which the spring rises, is a greenish talcose 

 slate, passing into mica-slate : it is in conjunction with limestone. 

 The temperature of the water is from 93° to 97° Fahrenheit. The 

 geological position of this spring, is more obvious than that of any 

 of the other thermal waters which I visited, being situated close to the 

 steep bank of the river Doron, where both the rocks are laid bare. 

 There are some warm springs on the opposite bank of the river, 

 which rise in limestone ; but the temperature is lower, owing to an in- 

 termixture with common water. 



Saute de Pucelle, or Virgi7i's Leap. — There is a very copious 

 thermal spring rising from the bottom of a perpendicular rock near 

 the Isere, between the town of Moutiers and St. Maurice, at the foot 

 of the Little St. Bernard ; but, owing to the difficulty of access to it, I 

 did not visit it, to ascertain its temperature. 



Beside the above thermal waters in the Pennine Alps, various ther- 

 mal springs were discovered in the adjacent Alps, near Grenoble, in 

 the year 1820 ; and it seems probable, that a series of these springs 

 might be found, were proper search made, extending westward to the 

 thermal waters of the Pyrenees ; for in this line we should approach 

 the southern border of the volcanic district of France. On the Ital- 

 ian side of the Pennine Alps there are also thermal waters : the warm 

 baths of Cormayeur and of St. Didier are situated almost immediately 

 under the southern escarpment of Mont Blanc. I was prevented by 

 the weather, from examining the geological position of these springs : 

 their temperature is stated to be 94° of Fahrenheit.* 



The inference that may be drawn from the geological position of 

 these thermal waters near the junction of the calcareous beds with 

 mica-slate, or the dark schist which passes into mica-slate, is, that the 

 waters do not rise from the upper strata, but spring out of the lower or 

 primary rocks ; and as they break out near the feet of the highest 

 range of the Alps, that extend from the northern side of the Simplon 

 through the Valais and Savoy into France, we may with much proba- 

 bility infer, that these mountains are situated over or near to one com- 

 mon source of heat, by the agency of which they were originally ele- 

 vated, and their beds placed in a position nearly vertical. This infer- 

 ence is in some degree supported by the well-attested fact, that the 

 districts where the hot springs are situated, are subject to great and 

 frequent convulsions, particularly in the upper valley of the Rhone. 

 In the year 1755, at Brieg, Naters, and Leuk, the ground was agitated 

 by earthquakes every day from the 1st of November to the 27th of 

 February ; some of the shocks were so violent, that the steeples of 

 the churches were thrown down, the walls split, and many houses ren- 

 dered uninhabitable : many of the springs were dried up, and the wa- 

 ters of the Rhone were observed to boil. At three different times the 

 inhabitants abandoned their houses, and fled for safety into the fields. 

 It has been before mentioned, that the mountain above the warm 

 spring at Naters, opened during the time of the great earthquake at 



♦ Nearly all the thermal waters in the Alps, emit sulphureous vapours, and are 

 slightly saline, except the waters of Leuk, which have the highest temperature, 

 and are inodorous, and free from saline impregnation. 



