43k GEOLOGY OF OHIO. 
in the western part of Clinton county where Todd’s Fork leaves the 
county, we shall find that the strata of stone seen under those we meet, 
proceed to the east, and if a well were dug deep enough at Washington 
or Wilmington, it would cut through all the strata found to the west as 
far as Cincinnati. A well sunk at Washington would first penetrate the 
strata overlying those exposed at Rock Mills, and passing through these 
would penetrate the strata represented on Paint Creek below Rock Mills, 
as at Rozers’s, and at James’s, and then would reach the stone so abund- 
ant on Rattlesnake from the line of the Washington and Leesburgh road 
to the south, and passing this would penetrate the water-lime building- 
stone of Greenfield and Lexington, and going deeper would penetrate 
the great Niagara system one hundred and fifty to one hundred and 
eighty feet thick, which is found immediately under the city of Wil- 
mington; cutting through this if would next reach the Clinton iron ore 
and then the stratified stone of this formation, about thirty feet in thick- 
ness, and then after cutting through three or four feet of a ferruginous 
clay would reach the Cincinnati group or Blue limestone, and in about 
one hundred and twenty-five feet would reach the strata which are seen 
in Todd’s Fork where it flows out of Clinton county. 
It has been stated that the average level of Fayette county is some | 
two hundred feet lower than that of Clinton county, while numerous 
formations overlie in Fayette county those found exposed in Clinton © 
county. The explanation is easy. It is observed that all the strata 
which have been named dip to the east. They do, indeed, dip more, 
rather than less, than sufficient to make up the difference in the level of 
the counties, and it is likely I have understated rather than overstated 
the difference in level, as it was impossible to get the levels of the Cin- 
- cinnati and Muskingum Valley Railroad, which would have enabled me 
to be more exact. I have calculated that the water-lime building-stone, 
asseen at Lexington and Greenfield, dips from thirty-five to forty feet 
per mile to the east (it dips also to the north). In fifteen miles the dip 
would be between five hundred and fifty and six hundred feet ; subtract- 
ing two hundred feet, the difference in level, there would be left three 
hundred and fifty to four hundred feet to be made up in Fayette county 
by additional strata. 
DENUDING AGENCIES. 
After the deposition of the rocks now found in Clinton and Fayette 
counties, the surface was not long, at any early geological period, beneath 
the surface of the sea. While the deposit of sandstone which extends 
almost fiom the very border of Fayette county to the south indefinitely, 
and to the east, underlying the coal, was being made, the land to the 
