52 J. J. STEVENSON — CARBONIFEROUS OF APPALACHIAN BASIN 



a mine only a mile and a half farther east have a fuel ratio of 4.4 and 

 4.6, so that in the interval the coal has changed from anthracite to semi- 

 bituminous, while it shows additional features which will be discussed 

 in another connection. It is worthy of note that at the latter locality 

 coal bed B is mined at 60 feet above bed A. Though the coal from the 

 lower bed has a ratio of about 4.5, that from the upper bed is anthracite 

 with the ratio of 10.3 * 



No notes are available respecting the petty area in Lycoming county, 

 but on the Allegheny crest in Clinton county Doctor Chance found 129 

 feet of Pottsville, with a coal bed 2 to 3 feet thick near the bottom of the 

 upper third, showing that the Bernice conditions extend thus far. In 

 Centre county, south of Clinton, Mr d'Invilliers finds about 255 feet of 

 Pottsville on the Allegheny front south from Snowshoe and describes it 

 as a massive sandstone with some layers of rounded white quartz peb- 

 bles, some as large as an egg. He makes no reference to coal.f The 

 general section of Blair county on the face of the Alleghenies as made 

 by Mr Sanders is 



Feet. Inches 



Sandstone 14 



Coal bed 1 



Fireclay 9 



Sandstone 100 



Concealed 100 



to the first exposure of red shale. The bottom sandstone becomes 

 coarser in the lower part.J Here one is perhaps 25 miles west from the 

 Broad Top field. 



Farther south in Bedford county one reaches the northern termina- 

 tion of the great syncline which deepens southwardly, so as to hold in 

 Maryland and West Virginia the important coal field known as Mount 

 Savage, Georges creek, as well as by other names in its more southern 

 portions. On its easterly side, within Bedford county, Stevenson found 



Feet. Inches 



Conglomerate 75 



Coal bed 4 



Shale and fireclay 20 



Coal bed 4 



Shale 5 



Sandstone with conglomerate 80 



in all, 184 feet. The upper plate is coarse, with pebbles as large as peas ; 



* A. S. McCreath, quoted by F. Piatt (G 2), p. 226. 



t E. V. d'Invilliers : Geology of Centre County (T 4), 1884, p. 52. 



% R. H. Sanders : Geology of Blair County (T) 1881, p. 12. 



