156 THE MOUNTAIN. 



In the geological theory of thermal springs, the observa- 

 tions of Professor Forbes and Dr. Daubeney find some con- 

 firmation in the position of the Yirginia springs, according 

 to Dr. W. B. Rogers, the geologist of that State, who points 

 out the association of thermal springs with anticlinal axes 

 and faults, showing that of " fifty-six springs mentioned in 

 twenty-five distinct localities within an area of 15,000 square 

 miles, forty-six springs are on or near axes, seven on faults 

 and inversions, and three the only group of this kind yet 

 known in Virginia near point of contact of hypogene, or 

 primitive with Appalachian rocks." 



The observations were made in the great limestone valley 

 of Yirginia, upon springs decidedly thermal, according to 

 ordinary acceptance, applying the term thermal, as Bischof 

 does, to " springs with temperature above the atmospheric 

 mean of the region in which they are situated." 



Professor W. B. Rogers considers that the "great propor- 

 tion of the copious and constant springs of the vast belt of 

 mountains occupied by the Appalachian range, especially 

 those of the great limestone valley of Yirginia, are truly 

 though slightly thermal, and that they owe to a deep sub- 

 terranean source the remarkable uniformity they exhibit." 



This excludes the formula of volcanism, as there are " no 

 volcanic or igneous rocks over the vast surface of the Ap- 

 palachian region ;" the source of heat being "hot strata in 

 the interior; the fractures and arches of the rocks being 

 the mere appliances mechanical, by which the water is ad- 

 mitted to the region of constant fires." 



Similar observations have been made by other geologists 

 in different parts of the world. 



The views of the New York geologists on this subject 

 have been already noticed, and Professor Mather's sugges- 

 tions on the range of continued northeast disturbances 

 alluded to. 



On the subject of the connection of mineral springs with 

 axes, we have also some interesting facts in the recent re- 

 port (for 1857) of Sterry Hunt to Sir William E. Logan, 



