128 Notice of Geological Surveys. 



The economical results of the present geological report are so 

 similar to those recited from the former, one, and so full an account 

 of eastern and central Ohio was given by Dr. Hildreth in Vol- 

 ume XXXIX, of this Journal, that a few extracts descriptive of the 

 geology of Butler and some adjacent counties, which is below 

 the carboniferous series, will suffice. The rocks in the south- 

 western portion of the state are thus described by Dr. Locke : 

 " The rocks in the western states below the coal formation have 

 evidently been deposited in the bed of a deep primitive ocean, 

 and consist of alternations and mixtures of crystalline and sedi- 

 mentary matters, mostly in thin layers, varying from one inch to 

 twe7ity four inches. The crystalline strata are mostly carbonate 

 of lime. The sedim^entary strata are, in the lower portions, clay 

 marl, and in the upper portions clay and sandstone. The mix- 

 tures are in the lower portions, lime and clay, forming either a 

 durable slate limestone, or an indurated marl which falls to pieces 

 on exposure to the air ; in the superior portions, of lime, clay, 

 and sand, forming an arenaceous limestone. All of these forma- 

 tions abound with the fossilized remains of marine animals." 



The arrangement of the rocks is shown in the following table, 

 beginning at the bottom. 



" 1. Blue limestone, (coming to the surface at Cincinnati and 

 all places within fifty miles of it,) in thickness at least 1000 ft. 



2. Clay marl, at West Union, Adams co. E. of Cincin., 25 



3. Flinty limestone, " " " 51 



4. Clay marl, " " " 106 



5. Cliff hmestone, " " " 89 



6. Slate, (black bituminous,) at Rockville, 251 



7. Waverley sandstone, east line of Adams county, 343 



1865 ft. 



" The country from Cincinnati to West Union, which stands 

 on an escarpment of the cliff limestone one hundred feet above 

 the surrounding region, is of a nearly uniform level, the various 

 elevated points, as ascertained by actual barometrical measure- 

 ment, differing not more than thirty six feet from each other, and 

 being usually five hundred feet above low water at Cincinnati." 



Dip. — " The strata are nearly horizontal, and having a slight 

 and irregular undulation, the dip is with difficulty ascertained," 

 causing it to appear " uniform and consistent for half a mile" in 



