58 BIO GRANDE COAL FIELDS OF TEXAS. [bull. 164. 
Prospect shaft No. 3 {worked seam) . 
Inches. 
Coal 28 
Bone 6 
Coal 16 
Reddish clay 3 
Coal 10 
White clay 2 
Coal 18 
Total 83 
This gives a total thickness of 72 inches of coal, with three divisions 
of slate. Whether all of this coal is marketable is not known. 
Mr. Peter W. Thomson furnishes the following information: 
Prospect shaft sunk 6 1-2 miles north of Eagle Pass. 
Ft. in. 
Gravel, sandstone, etc 45 
Coal 7 
Slate _..-. 2 
Coal 32 
Slate 2 
Coal 7 
Slate 2 
Coal 7 
Slate 3 
Coal 4 
Fireclay 10 
Coal 17 
Slate 4 
Coal 7 
Total coal, slate, and clay 104 
There are 81 inches of coal, with six divisions of slate or clay. 
Prospect shaft sunk in Olmos Creek bottom, 7 miles north of Eagle Pass. 
Ft. in. 
Gravel, sandstone, etc 39 
Coal 26 
Slate 6 
Coal 11 
Fireclay 6 
Coal 6 
Fireclay 16 
Coal 20 
Total coal, slate, and clay 91 
Giving a total of 63 inches of coal, with three divisions of slate and 
clay. 
