270 PHYSICAL GEOGRAPHY. 



fresh water passed close to the basin, so that one hand might be put into a scalding spring, 

 and the other in water of the temperature of 75. That of the spring was from 200 to 

 210. The waters joined below, and the united streams stood at 145, diminishing in 

 temperature until they entered the sea. No gas appeared to be disengaged from the 

 springs, in which the natives customarily boil their food, which is well done in about a 

 quarter of an hour. Strange as it appears to find hot and cold streams pouring from the 

 bosom of the earth within a few paces of each other, their subterranean courses may be 

 far apart, and be prosecuted under widely different circumstances, the one percolating 

 through substances which occasion the evolution of heat, or rising up from an immense 

 depth where it has been heated by interior fires, and the other confined entirely to the 

 superficial strata. When the Romans came into Gaul, they found a warm spring in 

 Provence, which furnished an abundant supply of water, and which received the name of 

 Aquce Sextice, from Sextus Calvinus, who established baths, and laid the foundation of 

 the modern city of Aix upon the spot. Through digging in the neighbourhood, about 

 a thousand paces distant, some cold springs were laid open, and the spring of Sextus gra- 

 dually diminished, and became perfectly dry. In 1721, the plague then raging at Aix, 

 the physicians declared that the warm spring would be highly beneficial for bathing, and 

 the other springs were accordingly stopped, and in twenty-two days that of Sextus re- 

 appeared. It seems evident, therefore, that their waters are identical, cold and hot within 

 the superficial distance of a thousand paces, but their passage from the one point to the 

 other is no doubt that of a descent to a great depth, where the warm temperature is 

 acquired, from whence they remount to the surface. 



Thermal springs are common in the Alps and Pyrenees, and in the districts lying 

 around their roots, particularly in the Grand Duchy of Baden, where they have occa- 

 sionally a very high temperature. The town of Baden was the Civitas Aurelia Aquensis 

 of the Romans, and possesses thirteen warm springs, the principal of which, called the 

 Ursprung, produces 7,500,000 cubic inches of water in twenty-four hours, with a tem- 

 perature of 1531. The temperature of the thermal springs on the northern side of the 

 Alps is Leuk, twelve springs, varying from 117 to 126; Naters, 86 ; St. Gervaise, 

 94 to 98 ; Aix les Bains, 114 to 117 ; MoutierS, 101 ; and Brida, 97. These springs 

 rise near the bottom of the great calcareous formation that covers the northern side of 

 the Alps, and near its junction with the mica slate that covers the granite. Mr. Bake- 

 well refers the temperature of the thermal waters of the Alps and Pyrenees to interior 

 combustion, to the agency of which, the original elevation of the mountains may be due ; 

 and the conclusion is supported by the fact, that the districts where the hot springs are 

 situated, have been subject to great and frequent convulsions, particularly the Haut Vallais, 

 where the temperature of the water is the highest. In the year 1755, at Brieg, Naters, 

 and Leuk, the earth was agitated with earthquakes every day for four months, and some 

 of the shocks were so violent, that the steeples of churches were thrown down, the walls 

 were split, many houses became uninhabitable, and the waters of the Rhone were observed 

 to boil. It is probably true of most hot springs, that they owe their temperature to 

 subterranean fire, as much as those in the neighbourhood of Vesuvius, though occurring 

 in countries where no indications of igneous action are exhibited by the superficial crust 

 of the earth. It is corroborative of this statement, that during the great earthquake that 

 destroyed Lisbon in 1755, the hot springs at Moutiers, in Savoy, ceased to flow for forty- 

 eight hours, and increased in quantity when they flowed again, a similar effect being 

 produced at the same time at the hot springs of Toplitz, in Bohemia. 



There are several tepid springs which appear to alter considerably in their temperature, 

 being warmer in the winter than the summer, an apparent variation merely, caused by 

 the real variation in the temperature of the atmosphere. There are warm springs, how- 



