Geology of the Muskingum Valley. 27 



wells. Four miles above McConnelsville, a deposit of grey or 

 liorncolored flint rock, comes to the surface and rises upon the 

 adjacent hills a short distance above ; at this town in boring for salt 

 water the flint stratum is reached at about one hundred feet, and 

 it continues to dip at. nearly the same rate for ten or fifteen miles 

 below. This rock is a certain guide for the well diggers, as the main 

 salt rock is very uniformly found at six hundred and fifty feet below 

 it. At the lower wells on the Muskingum, twenty five miles from 

 the mouth, the salt rock is reached at nine hundred feet from the 

 surface. Some wells at these salines, are sunk more than three 

 hundred feet below the present surface of the ocean, and the salt 

 rocks, generally through the valley of the Ohio, lie below tide wa- 

 ter. The rock strata below the surface, are similar to those passed 

 at the other salines in the west, being a series of yellow and grey 

 sandstones, slate clay, red argillaceous marls, bituminous coal, shells, 

 flint, red or brown sandstone, calcareous rocks, and finally pure 

 white saccharine sand rock, containing a small portion of silvery 

 mica, in which the excavations terminate, and in which the only 

 strong and lasting supply of brine is found, throughout the salt region. 

 It is porous, and full of cavities, affording a free circulation to the 

 water ; the augur sometimes dropping several inches, at once into 

 one of these cavities. At the Muskingum salines there are two stra- 

 ta of this rock which afford salt water — one at about two hundred 

 feet below the siliceous rock, twenty four feet in thickness, affording 

 good water but not in sufficient quantity. It is more compact than 

 the lower rock but it is not of so pure a white. The second lies at 

 about four hundred and fifty feet below this, and is from forty to 

 fifty feet in thickness. The upper part of this rock is sometimes 

 tinged with red. In all the salt wells on the Muskingum a stratum 

 of rock is passed, known to the workmen by the name of the lower 

 hard rock. At McConnelsville it is struck at six hundred and twen- 

 ty feet below the surface, or about one hundred and eighty above 

 the lower salt rock, lying between these two rocks. It is about 

 forty feet in thickness and possesses some singular properties. From 

 Mr. Stone, a very intelhgent man who was for many years engaged 

 in the salt business, I received the following description. Where he 

 pierced this rock it is forty two feet thick and the boring occupied 

 forty five days of labor. Through its whole depth, it is very dense 

 and compact, and in particular veins, or beds, possesses great tena- 



