lxXXvi REPORT OF THE STATE GEOLOGIST. 



in the vicinity of Yan Horn and further north in the Guadaloupe Moun- 

 tains. They are reached by a well eight hundred and thirty-two feet 

 deep at Toyah, some seventy miles east of Van Horn. This well has 

 an abundant flow. We have, therefore, in the lower members of the 

 Carboniferous rocks of this basin water-bearing strata, the exposed 

 edges of which on the southeast and west are sufficiently elevated to 

 furnish artesian water to portions of the basins in their immediate vi- 

 cinity. 



We do not know what interruptions to the subterranean flow may 

 exist in the way of dikes or fissures, and therefore the areal extent of 

 this portion favorably situated can not be given until the topography 

 and geology are better known. The quality of the water from every 

 well thus far secured in this basin, which has its origin in this series of 

 rocks, is highly saline, and it is safe to assume from this and from the 

 character of the deposits that no fresh water can be obtained from this 

 source. Therefore, if the supply be general over the entire region, it 

 will only be adapted for limited uses. In addition to this, this water- 

 bearing bed can be reached in the greater portion of the region only 

 after passing through the entire series of Permian strata and those of 

 the uppermost Carboniferous, amounting in all to two thousand or three 

 thousand feet, or even more in places. 



If there be any other hope for an artesian water supply in this region 

 the catchment area must be either in the pre-Carboniferous rocks of the 

 Central Mineral Region and the Wichita Mountains or in the Guadaloupe 

 and connected ranges. That such a catchment area exists on the south 

 is fully proved by the powerful springs at Lampasas and in San Saba 

 County, all of which have their origin below the rocks of Carbonifer- 

 ous age. Some of these springs, such as the Lampasas, have their vent 

 through rocks of this period, but they belong to the very lowest strata, 

 and the temperature of the water proves that it comes from still greater 

 depths. All such water is highly mineralized, but much of it seems 

 suitable for general uses after exposure to the air has dispelled the sul- 

 phuretted hydrogen. Others of these springs, like that at Cherokee, 

 San Saba County, spring through rocks below the Carboniferous, and 

 these furnish water of an excellent quality. The dip of these rocks is 

 much greater than the overlying Carboniferous, and the water supply 

 would therefore be rapidly carried beyond the depths of ordinary arte- 

 sian borings. The conditions of outcropping strata are similar in the 

 Wichita Mountains to those of Llano and San Saba counties, but we 



