Page:Report on the geology of the four counties, Union, Snyder, Mifflin and Juniata (IA reportongeologyo00dinv).pdf/274

246 F³. miles east from Logan gap; and as they have always supplied their wants from other localities, there has been no occasion to institute developments in this portion of their territory. The Clinton rocks rise well up the flank of the mountain, so that the dip will be quite steep, and whereever the ore ridge has been cut down by small mountain streams a considerable quantity of favorably located soft fossil ore should exist. Owing to the high dip of the rocks (50°–60°) the space between the mountain and the Limestone ridge is greatly contracted towards the Union county line, and as there are but few water gaps in this ridge, the ore in the mountain is not very accessible.

The Devonian rocks No. VIII occupy nearly half the area of the township and have a total thickness approaching 2500′ on the eastern end. Westward from this point the synclinal valley shoals up, so that west of Lillyville only the Marcellus and Genessee slates are contained in the trough between the railroad and the Flagstone anticlinal ridge to the north; while the narrow vale between this ridge and the second anticlinal before mentioned contains only the Marcellus black slates, here largely concealed by sand drift from the two Oriskany ridges.

At A. Bishop’s place in this vale some carbonate iron ore, decomposed at its outcrop to hematite, has been found; but no openings have been made. It is probably an eastern extension of the valuable bed so successfully mined at the Townsend mine of the Logan Iron and Steel Company in Derry township.

The crest of the ridge north of this narrow vale is composed of the Oriskany sandstone measures, here very largely decomposed and making a flat or plateau of white and yellow sand.

Bishop’s limestone quarry, a little east of the road crossing, had developed some fairly good beds of a blue and grey, rather crystalline limestone, dipping S. 30° E. 50°. The quarry is small and is possibly located in Derry township. The limestone in the north leg of the anticlinal is