110 THE ALLEGHANY COAL FIELD. 



Feet. 



16. Shale, 50 



17. Sandstone and Shale, 75 



18. Coal, 1 



19. Shale, very thin, 



20. Argillaceous Sandstone, level of low water at Pitts- 

 burgh, one hundred and forty feet above Lake Erie, 30 



21. Shale, red and blue, 30 



22. Coal, to base of " lower Sandstone group," - - 1^ 



450 



No. V. 



SECTION OF COAL ROCKS FROM LAUREL HILL WEST TO THE 



MONONGAHELA RIVER. BY MR. C. BRIGGS, GEOL. REP. OF VA., 



1841. 



Feet. 



1. Conglomerate, 



2. Shale, 10 



3. Sandstone, 4 



4. Shale and Iron Ore, very thin, 



5. Sandstone, 30 



6. Shale, 18 



7. Coal, 2i 



8. Flaggy Sandstone and Shale, 30 



9. Coal, 1 



10. Flaggy Sandstone and Shale, 40 



11. Limestone, 4 



12. Shale, - - - - 10 



13. Sandstone, 5 



14. Shale, 6 



15. Coal, li 



16. Shale, 12 



17. Coal, - - - 3^ 



18. Shale, 35 



19. Coal, 5 



20. Sandstone, Morgantown, base of "lower Sandstone 



group," 60 



277 



