30 " Putnam Hill Strata. 



living species now found in our rivers. For a notice of No. 20, 21 

 and 22, (page 1 of the wood cuts,) see the appendix. 



Through nearly all the coal region we find many proofs of the 

 predominance both of freth and of salt water. West of the coal 

 deposits in Ohio, the fossil shells are altogether marine, at least so 

 far as I have seen them, and many of them belong to the supercre- 

 taceous or tertiary genera, and are similar to those found in the same 

 formations in the Southern States. 



A section of the rock strata near Zanesville, will give a satisfac- 

 tory view of the geological structure of this portion of the valley ; 

 and for this purpose, I have chosen a lofty hill on the west side of 

 the river, called " Putnam hill." The scite of the town of Put- 

 nam, lying along its southern base was selected in the early settle- 

 ment of the state, by General Rufus Putnam, and the town was na- 

 med after him. The Muskingum river coming down from the N. 

 E. here makes a bend, sweeping the base of the hill, and tumbling 

 and foaming over the hard ferruginous limestone that forms its bed. 

 This hill, at some remote period, was united in continuous strata 

 with its congener of nearly the same elevation on the east side of 

 the river. But the waters, which have made such changes on the 

 surface of the earth, accumulating from the regions higher up the 

 valley, here forced a passage, tearing away the sand rocks, slate 

 clay, coal and shale, down to its present bed, leaving the face of the 

 hill very abrupt ; and with the assistance of a road excavated out of 

 its side, affording a fine view of the thickness and order of stratifi- 

 cation. 



1. Argillaceous earth and clay, from the decomposed sandstone 

 forming the stratum beneath. — 10 feet. 



2. Argillaceous sandstone. Slaty structure, tinged yellowish by 

 the oxide of iron and containing imbedded nodules of argillaceous 

 iron ore. The lower part of the bed dark colored. — 10 feet. 



3. Carbonaceous, slaty clay, with bituminous shale, containing 

 thin seams of coal the thickness of paper, the coal still retaining the 

 outlines of the vegetable foliage impressed on the shale. It is a 

 thin bed of only one foot in thickness. Some of the impressions are 

 sirnilar to those found in Section No. 12. — 1 foot. 



4. Bituminous coal. Structure foliated, splitting into thin lay- 

 ers. Color inclined to dark brown. Specific gravity 1 .22, being 

 rather less than the average for common coal. In deflagrating with 

 the nitrate of potash, twenty grains of the coal consume one huri- 



