ASHLAND COUNTY. 525 



The Olive Shales No. 3, of the section, are by no means homogeneous 

 in structure. At all levels they pass into rich, thick layers of quarry rock, 

 some of it quite coarse and approaching the character of a Conglomerate. 

 Occasionally, thin argillaceous strata are observed, and more rarely beds 

 of impure, Fossiliferous limestone. 



About one mile north of Loudonville, on the road to Hayesville, a 

 quarry of this rock is opened near the top of the hill, and one hundred 

 and forty-five feet above the valleys in the immediate neighborhood. 

 The hill forms part of a ridge extending nearly north and south with 

 the valleys on each side. The rock is all silicious, of a yellow, olive 

 color, some of the compact layers reaching a thichness of three and four 

 feet. All the strata were originally evenly bedded in horizontal layers. 

 They are now broken up to the center of the hill with lines of irregu- 

 lar fracture, the strata crushed and displaced, showing the result of a force 

 exerted upon each side of the hill, which has crushed the rocks as a ship is 

 sometimes crushed in the polar ice. A few characteristic Waverly shells 

 are to be seen in the upper layers of the quarry. The hiils here, and to the 

 north and north-east, have well rounded outlines, with graceful curves, 

 showing that the rock-cores are substantially homogeneous in structure. 



The following is a section of that part of these rocks exposed in T. S. 

 Sutherland's quarry, one and a half miles south of Ashland village : 



FT. 



Drift clay 10 to 12 



Sandy shale, with hard layers at bottom 6 



Limestone, with a profusion of shells Ito li^ 



Shaly sandstone .. 8 



Sandstone, in layers of 18 inches to 4 feet, to the bottom of the exposure. 



This quarry is capable of furnishing a large quantity of fine-grained, 

 hard stone, strong and durable, and blue in color, but, like nearly all the 

 rock from this formation, changing to a yellow on exposure to the air. 

 This change is primarily analogous to that observed in the oxydation of 

 the l^ue to the yellow clay of the drift, and the contrasts of color are 

 about the same in both cases. 



The third band of limestone, near the top of the section, is crowded 

 with the ordinary shells of the Sub-carboniferous rocks, and is of interest 

 as pointing to the source of the limestone bowlders frequently found on 

 the margins of the c;oal fields, and filled with similar shells. Several of 

 these were observed in Summit county, and were easily recognized as 

 difiiering from the bowlders of the Corniferous limestone, which are still 

 more abundant. No deposit of such rock is known in that county, or 

 directly to the north of it. But wherever denuding agencies have 

 broken up the strata containing such a layer as this, it is easy to see, 



