178 



feet thick, is hard and black and full of prints of ferns ; the 

 bottom slate is gray and softer, and without traces of fossils. As 

 the mines in this Coal-bed contain but little timbering, and the 

 roof-slate is left in its place exposed to view, this presents to the 

 observer a fine opportunity for studying the fossil plants on its 

 naked surface. These are remarkably numerous and distinct, 

 looking like a painting of the surface of some luxuriant meadow, 

 pressed down. Those who doubt that the long and slow ac- 

 cumulation of vegetables growing on the spot has formed these 

 beds of combustible matter, should come and witness this mani- 

 fest proof written on the rocks in indestructible language. Not 

 only the trunks and leaves are preserved entire, but in many 

 places you may follow a stem in its branchings to its smallest 

 subdivisions, and most delicate thread-like processes. That the 

 vegetation of the coal was sometimes very uniform over a large 

 surface, perhaps the whole extent of a coal-bed, as affirmed by 

 Humboldt, Brongniart, Lindley, and other good authorities, is 

 here demonstrated ; for though the mines are worked extensively 

 around Pomeroy, I nowhere met with any but the three species 

 which characterize the Tunnel Vein of Pottsville ; namely, 

 Neuropteris cordifoUa, and its stems, N. heterophylla, finely- 

 striated Calamites ; the chief portion of which latter are but parts 

 of the stems of ferns, though of the form described by many 

 authors as Calamites, 



Wheeling. The following is a section of the strata at Wheel- 

 ing, above the Coal-bed there wrought. The thicknesses are 

 only approximately correct. 



1. A Sandstone forms the Capping-rock. 



2. Cannel coal and Soft coal, 1 foot. 



3. Sandstone, 10 to 15 feet, (not exact.) 



g* j Limestone, 85 to 45 feet, hard above, shaly below. 



6. Shales, 15 feet. 



7. Hard Sandstone, 2 feet. 



8. Limestone, 20 feet. 



9. Shales, 2 feet. 



10. Brittle coal, 1 foot. 



11. Ferruginous Shales, 2 feet. 



12. Limestone, 20 feet. 



13. Shales, 2 to 3 feet. 



14. Coal bed, wrought. 



The bed, No. 2, is a thin seam of coal, which, in its superior 



