248 STRUCTURE AND ACTION OP "VOLCANOS. 



( 3 ) p. 239. " Waters of springs rising from different 

 depths?' 



Compare Arago in the Annuaire du Bureau des Longitudes 

 pour 1835, p. 234. The increase of temperature is in our 

 latitudes 1 of Eeaumur (2.25 of a degree of Fahrenheit) 

 for every 113 Parisian feet (120.5 English feet), or 1 Fah. 

 to 53.5 English feet nearly. In the Artesian boring at 

 New Salzwerk (Oeynhausen's Bad), not /ar from Minden, 

 which is the greatest known depth below the level of the 

 sea, the temperature of the water at 2094J Parisian feet 

 (2232J Eng.) is fully 26.2 Eeaumur, or 91 Fahr.; while 

 the mean temperature of the air above may be taken at 7. 7 

 Eeaumur, or 4 9. 2 Fahr. It is very remarkable that in the 

 third century Saint Patricius, Bishop of Pertusa, was led 

 by seeing the hot springs near Carthage to a very just 

 view respecting the cause of such an increase of heat. 

 (Acta S. Patricii, p. 555, ed. Euinart; Kosmos, Bd. i. S. 

 231, English Edition, Vol. i. p. 211.) 



