157 



t Lesley. 



A geological cross-section of this valley, taken almost anywhere, is 

 something- like this : — Fit;. 1. 





&& 





< s 



it*- 





Alltfkany <Mtn . 



The only notable variations from the above cross-section occur at three 

 far distant points : 1. At Muncy, where the fossil ore flattens and sweeps 

 round the northeast anticlinal end of the Bald Eagle Mountain ; 2. at 

 Frankstown and Holidaysburg, where the fossil ore flattens and sweeps 

 round the southwest end of Bald Eagle Mountain and the northeast end 

 of Dunning's Mountain ; 3. North of Bedford ; where in a precisely 

 similar style, the fossil ore beds, the red shales in which they lie embeded, 

 the limestone formation (VI) over the red shale (V), and the Oriskany 

 sandstone (VII) all flatten and sweep in concentric semi-circles round the 

 southwest end of Dunning's Mountain, a ridge of rock extending from 

 Holidaysburg to St. Clairsville, about 20 miles. This mountain opposite 

 St. Clairsville makes a right angle and runs east several miles, and then 

 makes another right angle, and resumes its south-southwest course, past 

 Bedford, into Maryland. 



The fossil ore beds follow its flank. 



Where the mountain runs its regular course the fossil ore beds are 

 steep (nearly vertical) and their outcrops lie high up on the mountain 

 side. 



But where the mountain makes its offset to the eastward the fossil ore 

 beds (and other formations) lie flat, dip south at gentle angles, and their 

 outcrops are far removed from the base of the mountain. 



The region specially examined in this case sweeps round with the ore 

 beds ; having them steep on the mountain side at its north and north- 

 west end — having them flat and away from the mountain (on Black Oak 

 Ridge) in its middle portion — and having them again steep and up the 

 mountain side, at its eastern and southern end. Geographically, it begins 

 at St. Clairsville (its northwest end) ; extends three miles southward 

 along the east slope of Black Oak Ridge ; then half a mile eastward; and 

 then three miles northeastward into Dutch corner. Its St. Clairsville 

 end is ten miles from Bedford; its Dutch Corner or southeast end seven 

 miles. 



The surveyed line of the Bedford and Dunning's Creek Railroad passes 



