REPORT OF THE STATE GEOLOGIST. xliii 



ager of the Johnson, or Texas and Pacific, Mine. The quality of coke 

 produced gives every promise that, with proper care in selecting mate- 

 rial and attention to burning, it will produce a coke fully adapted for 

 the best metallurgical uses. 



In addition to this Central Coal Field there are others on the western 

 borders of the State. One of these, the Nueces Coal Field, was de- 

 scribed in the First Eeport of Progress of this Survey, and again in the 

 First Annual Report. Since that time a boring made at Eagle Pass, 

 four miles from the outcrop on which the Hartz Mine is situated, reached 

 the same coal at five hundred and thirty-one feet. This coal cokes in 

 the crucible, and there is no doubt but that an excellent coke can be 

 made from it, if ovens of suitable construction are used. 



This seam is the thickest in the State, averaging nearly five feet, and 

 must prove of very great economic value. 



A second coal field is that containing the deposits in Presidio County 

 between the Capote Mountain and the Rio Grande. The specimens of 

 this coal which have been furnished for analysis show it to be very 

 high in sulphur, but no detailed examination of it has yet been made. 



BITUMEN OR ASPHALTUM. 



This valuable material exists in Texas under several conditions. Its 

 most frequent occurrence is probably in tar springs. These are found 

 in many places in the Tertiary and Cretaceous formations, and occa- 

 sionally among those that are older. It is in these cases the seepage 

 from the beds which contain it. So far few, if any, of these beds have 

 been examined to ascertain their extent or quality, for there has been 

 little or no demand for the material. Among these may also be in- 

 cluded the Sour Lakes of Hardin and Liberty counties, at which both 

 bitumen and gas occur in large quantities. 



In other places it is found as deposits of greater or less extent, im- 

 pregnating the accompanying sands, sandstone, and limestone. These 

 have not been given much more attention than the springs, but some 

 of the localities have been examined and specimens of the material 

 analyzed. 



The tar springs are of frequent occurrence in certain beds of the 

 Timber Belt Series, which stretch across the State in a belt approxi- 

 mately parallel to the Gulf coast and from 100 to 150 miles inland, 

 and are at places connected more or less with deposits of oil. 



They are also found along the belt of country underlaid by the Fish 



