MURPHREE'S VALLEY; ECONOMIC GEOLOGY. 83 



Just below the body of iron ores last described, the Clin- 

 ton sinks again beneath the surface. For a mile it is en- 

 tirely engulfed, and the greater part, sometimes all, of the 

 Lower Siliceous also. The LaGrange and the lower mem- 

 bers of the Silurian (Knox) Chert join together at the fault. 



Opposite this sunken portion of the Clinton, in S. 26, the 

 LaGrange or Oxmoor Sandstone is a very massive, vertical 

 ledge, through which flows that branch of Village Creek 

 which rises in Spradling's Cove, or "Wild Cat Cove" as it is 

 often called. The region up this branch presents some very 

 notable features. On the left or eastern side is a large ex- 

 posure of Carboniferous or Mountain Limestone, flanking 

 the south western end of Raccoon Mountain Coal Field. A 

 vertical thickness of about 200 feet of the limestone is showr* 

 here, and much of it of very good quality. Its base covered 

 by talus is nowhere seen from the edge of Murphree's 

 Valley to Wild Cat Cove. While on the opposite or western 

 side of the branch at the same level is found only Lower 

 Siliceous rocks and LaGrange Sandstones. And a half mile 

 farther west the LaGrange is at a higher level than the 

 opposite limestone. A very considerable difference of level 

 produced either by fault or flexure exists here. On entering 

 the Cove still greater complications of strata are seen. The 

 floor of the Cove is of Carboniferous Limestone, and Lower 

 Siliceous Chert ; its western margin of LaGrange Sandstone, 

 its eastern and southeastern side is Trenton Lfmestone and 

 Clinton Strata, both vertical at the edge of the Cove and 

 also showing much difference in level at different points. 

 On the lands of George Chamblee in S. 11, T. 15, R. 1 W., 

 on a seam of iron ore, the difference of level is over 100 feet 

 in a space of 125 yards. The identity of the seam as seen 

 at both places could not be mistaken. Both places showed 

 about the same thickness, the same ore, the same underly- 

 ing rocks. On the east side, where it was dipping very 

 gently to the northwest, the bed was well exposed, showing 

 upwards of four feet of soft, fine-grained, dar colored ore, a 

 little better in quality than the general average of this bed. 

 There is no question of its identity. This is the 5th bed, and 



