2 Introductory Views. 



I 



a thousand feet, without reaching the pnnaitive rocks. That the 

 primitive rocks lie at a great depth may be inferred also from the 

 color of the sandstone rocks, none of them being red, except where, 



4 



in the mountain ranges, they are bordered by, or resting on the transi- 

 tion series ; the color being probably produced by the heat im- 

 parted to the derivative rocks, by the primitive strata when in a state 

 of fusion, which, as we have the best ground to believe, was once 

 the condition of all crystalline rocks. Fragments of the sandstone 

 rocks, through all parts of the valley are easily changed to red, by 

 subjecting them to the heat of a strong fire,' showing that they do 

 not lack the chemical constituents of the old red sandstone, and 

 that they have not been exposed to any great heat. 



In the vicinity of '^ Flint ridge," which is evidently a deposit from 

 hot water, I have seen sandstones highly colored with veins of red, 

 but in every other place near the center of the valley, which I have 

 visited, they are universally grey, ash colored, or brown, according 

 to the tint of the silex, mica, lime, or clay, which entered into their 

 composition. 



That the change was gradual from the condition of an ocean to 

 that of dry land, is also inferred from the slight inclination, or slope 

 of the northern side of the valley, taking the present bed of the 

 Ohio river for the center, or most depending part. Tlie elevation 

 of the surface at the heads of the Muskingum and other streams, 

 which take their rise in the table lands between Lake Erie and the 

 Oliio, being only about four hundred feet above the mouth of the 

 former river, having a descent of a little over two feet to the mile. 

 On the south side, the slope is equally gradual, until the ranges of 

 ♦ hills connected with the mountains make their appearance at a dis- 

 tance of from fifty to seventy rniles frcm the Ohio ; the rise then be- 

 comes much more rapid, averaging, in some places, especially on , 

 the New river, above the mouth of Gauly, fifteen or twenty feet to 

 the mile, for the distance of forty or fifty miles. Those portions of 

 the ancient ocean's bed, lying near and on each side of the region 

 now occupied by the Ohio river, were, doubtless, for many ages, cov- 

 ered by lakes of fresh water, after the more elevated parts, had be- 

 come dry land, and were clothed with vegetatipn. We are led to 

 this conclusion from the numerous deposits of lacustrine and fresh 

 water shells found in the sandstones and marls in the hilly portions 

 of the valley near the Ohio river ; and after the waters had been so 

 far dramed off as to lay bare the bottoms of these lakes, it must have 



