OBSERVATIONS ON TYPHLOMOLGE RATHBUNI. 



93 



down along the slanting stratum beneath the geologically higher 

 situated Edwards limestone and towards the fault. Along the 

 fault, however, the continuity of the water-bearing strata is 

 broken and they come to lie in one level with the Edwards lime- 

 stone of the plain ; thus, here the water is forced from the Glen 

 Rose formation into the Edwards limestone. 1 



fe l-~f 



H<H^t (blQ\ 



abo 



V'VVY\, - 



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FIG. 12. Ezell's Cave. Balcones scarp line and Artesian Well of U. S. 

 Fish Hatchery in San Marcos, Texas. Diagrammatic section showing the 

 position of northern and southern part of the various cretaceous formations 

 to each other after the dislocation of the Rio Grande Plain in Eocene time 

 accomplished by faulting. The figures on the left-hand side of the diagram 

 indicate altitude above sea level in feet. 



The water of Johnson's Well, Ezell's Cave and Beaver Cave, 

 however, is the river water of the subterranean Purgatory Creek. 

 The level of the Purgatory Creek in these localities at present is 

 at an altitude of about 580 feet, that of the Artesian Well 360 

 feet. 



Hill and Vaughan, page 315. 



