WITH ANTICLINAL AXES AND FAULTS. 331 



The details embraced in the preceding tables of our thermal 

 springs, will, I think, justify the assertion, that in no region hitherto 

 described is the connection of springs of this class with the struc- 

 tural features of the district in which they occur, so uniformly and 

 extensively displayed as in our Appalachian belt. The fifUj-six 

 springs here enumerated embrace twenty-five distinct lines and 

 individual localities, situated in various and remote parts of the 

 valley, and the mountainous belt adjoining it on the northwest, 

 making in all an area of about fifteen thousand square miles. 

 Forty-six of these springs are situated on or adjacent to anticlinal 

 axes, seven on or near lines of fault and inversion, and three, the 

 only group of this kind yet known in Virginia, close to the point 

 of junction of the Appalachian with the Hypogene rocks. 



It may therefore be announced as the prevailing laiv, as regards 

 the more decided thermals of Virginia, and I have reason to be- 

 lieve of other parts of the Appalachian belt, that they issue from 

 the lines of anticlinal axes, or from points very near such lines. 



A glance at the several short sections accompanying this paper, 

 aided by the following brief comments, will serve more particu- 

 larly to illustrate the conditions under which they thus generally 

 occur, and to impart just conceptions of the structure of the dis- 

 tricts in which they are situated.* (Plate XVI.) 



Section I. From the Warm Springs to the Little North 

 Mountain. 



Section II. Passing through the Hot Springs. 



Section III. Passing through the Gap Spring and Ebbing 

 Spring. 



Section IV. Through axis at Keyser^s Springs. 



In the first of these Sections are embraced three thermal local- 

 ities, presenting distinct geological conditions. In the most 

 western, that of the well-known Warm Springs, the water comes 

 to the surface in the line of an antichnal axis. In the next, that 

 at the Mill Mountain, it flows out on the southeastern side of the 



* The scale of the Sections is two and a half miles to the inch, or twice that of the large 

 State map. The eastern part of Section VIII is, by mistake, too much expanded. 



