15. SPRING TOWNSHIP. F 2 . 335 



The Clinton Lower green shale, ( V. ) 



These beds form the crest of the Blue mountains, but- 

 tressed on the south by the Medina and on the north by 

 the Iron sandstone next to be mentioned. 



The Clinton iron sandstone, &c, ( V.) 



These hard, dark-purple, resisting beds form the northern 

 edge of the crest of the Blue mountain in the township. 

 In this part of the county the iron sandstone attains a much 

 greater thickness than in the northeast and rivals the Me- 

 dina in mountain-making power. Its thin, flat, but almost 

 indestructible, plates strew much of the red shale land 

 spoiling what would otherwise be well adapted for cultiva- 

 tion. They are carried along by the streams and lie along 

 the banks of every water course which passes near or over 

 the outcrop, often exciting curiosity regarding their mineral 

 value in places where they are not. otherwise familiar. It 

 need not be said that their mineral value is "nil." 



The higher beds of the Clinton occur only on the slope 

 of the Blue mountain, and need little mention. The ore 

 sandrock and upper green shale are both concealed for the 

 most part, and I have seen no exposure of the Sand-vein 

 ore bed in the township. 



The Onondaga shale, (V.) 



The northern outcrop of this shale in Spring township is 

 the summit of the eroded Bloomfield anticline, which is 

 here cut down so far that the variegated shale is exposed 

 over a space about a mile in width between Limestone and 

 Mahanoy ridges. Over this tract runs the main road up the 

 valley through Elliotsburg. The higher beds of the Onon- 

 daga should be exposed on both north and south sides of 

 the valley, but much of their surface crop is deeply covered 

 with the wreckage from the limestone and Oriskany sand- 

 stone. 



A small tongue of the same red shale also runs up south 

 of Bell's hill or BelV s Cop, but it requires no special notice. 



The great tract of shale in this township is that around 



