212 COAL FIELDS OF THE COLORADO RIYER. 



beds near the base, contain great quantities of argillaceous matter, and if coal 

 were present it would very likely share the same fate and contain so much 

 ash that it would be more a carbonaceous shale than a coal. This is what 

 is noticed in some of the many thin coal seams of the Coleman beds. 



ECONOMICS. 



Coal. — In considering the question of the amount and value of the coal in 

 the Central Texas area, as based upon the foregoing geological facts, the best 

 that can be done is to make a statement of the probabilities. To test the 

 truth of my inferences and the value of my judgment the drill or the spade 

 must be used. The amount of prospecting that has been done in the Car- 

 boniferous area is far too scant to admit of final and accurate statements con- 

 cerning the economics of the coal; yet I have no doubt that further explora- 

 tion will prove the truth of my general statements, and it is with confidence 

 that I make them. 



The lowest coal seams that have been noticed are those in the Sub-Carbon- 

 iferous at San Saba and Brady. They are only a few inches in thickness, 

 and are the best that can be expected from this region. In the Carbonifer- 

 ous proper the amount of barren territory is astonishingly large. The total 

 thickness of the true Carboniferous along my cross-section, calculated on a 

 basis of a regular dip of 100 feet per mile, is nearly 8000 feet, and in all this 

 area there are but two series of beds which promise coal, and only one that 

 has so far been proved to contain workable coal. The total thickness of 

 these two coal bearing series is but 450 feet, or only one-eighteenth of the en- 

 tire thickness of the Carboniferous. 



In the entire cross-section there are not more than five feet of coal, or one- 

 sixteen-hundredths of the entire formation. Two-thirds of the beds are ab- 

 solutely barren. The Richland Sandstone beds are barren; the Brownwood 

 Beds contain no coal; and the Coleman Beds, although having numerous 

 thin seams of carbonaceous shale and laminae of coal, probably contain no 

 beds of workable coal. Traced to the north beyond the area which I have 

 described, these beds may change in character in such a manner as to become 

 coal bearing. Certain indications seem to point to this conclusion. 



Of the Milburn series little that is definite can be said. No regular pros- 

 pecting has been done. In many wells coal has been found, but nowhere in 

 workable quantities. The beds in this series are certainly suggestive of coal, 

 but south of the Colorado, in the vicinity of Milburn, there is probably no 

 workable coal. It is reported to be two feet thick in a well just west of Mil- 

 burn, and to have a vertical dip; but if such is the case the coal is locally out 

 of place. If any workable coal exists in the Milburn series southwest of 



