vauqhan.] EOCENE COAL FIELDS. 63 
D. D. Davis at Pilot ranch, 25 miles wesi of north from Santo Tomas, 
and ;>A miles from Rio Grande, is given on pages 42 l<> II. There is 
another outcrop <A' coal 2i miles north of Palafox. 
At Santo Tomas there are two mines, that of the Rio Grande Coal 
and Irrigation Company, which is in the village, and that of the Can 
nel Coal Company, which is 3 miles southeast of it. The record of 
the prospect drill bored at the latter mine has been given <>n pages 
1 1 to \'2. In the ( annel ( \>al ( Jompany's mine there are two seams, the 
upper one being called the Santo Tomas seam (Rio Grande Coal and 
Irrigation Company), and the lower one, known as the San Pedl'O 
seam, being worked by the Canne] Coal Company. 
Section of the Santo Tomas seam. 
7. Carbonaceous shale roof, soft, requires considerable timbering. n in 
(>. Coal o M 
5. Bone o l 
4. Coal o II 
:>'. Bone - 6 
2. Fireclay 7 
1. Sandstone, 
Section of the San Pedro seam. 
Ft. in. 
8. Clay slate or sandstone II 
7. Carbonaceous shale... n .', 
(i. Coal, upper bench 2 () 
5. Bone L5 
4. (lay 2 
3. Lower bench : 
c. Good coal 1 1 
6. Bone 2 
a. Good coal <> 1 1 
2. ( Jarbonaceous shale <» 
1. Sandstone II <> 
The following is extracted from Dumble's Brown Coal and Lignite, 
page 189. 
The most northern exposure of this coal observed in Webb County was about 25 
miles northwest of Santo Tomas, where a seam of pitch coal was found which was 
black, massive, dense, and s<» firm that it does not give a greasy streak with finger 
nail. No trace of wood structure, subconchoidal fracture. 
About 8 miles west of Santo Tomas, at Espada Creek, we find three seams of brown 
coal. 
The upper seam is 12 inches thick, and is a massive pitch coal with conchoidal 
fracture, very similar to the body of the Santo Tomas coal. It is underlaid by I feel 
of shale, and this by the Santo Tomas seam of coal, which is here.';! inches thick with 
a 2-inch division of slate. This coal is underlaid by 30 feel of shale, helou which is 
a third seam of brown coal, varying in color from lighl to dark brown, with many 
traces of woody structure, impressions of leases, etc. 
