WELLS OF CLAY COUNTY, ILLINOIS. 757 



through Fox River, a tributary to the Little Wabash. This county, like 

 those to the north and west, has a coating' of white clay which is very slowly 

 pervious to water. The excess of rainfall escapes largely through evapora- 

 tion. Along the streams and in lowlands there is usually a black mucky 

 soil, much richer than the white clay of the uplands and more readily per- 

 vious to water. 



On the uplands the drift is generally very thin, the rock often being 

 entered at only 10 or 15 feet. On the lowlands the thickness is much 

 greater, and wells are obtained at 20 feet or less without entering the rock. 



INDIVIDUAL WELLS. 



r 

 At the city of Olney private wells usually obtain water at a depth of 



10 or 12 feet from a gravelly bed resting on the rock. The waterworks 

 supply, which is chiefly for fire protection and lawns, is pumped from Fox 

 River. A boring 2,000 feet in depth was made at this city for the purpose 

 of obtaining- an artesian well. A salt water was struck which does not over- 

 flow, and no use is made of the well. South of Olney, near Parkersburg, 

 a well is reported to have struck wood in clay at 20 feet, 



In the north part of the county, near Dundas, rock is usually entered 

 at 12 to 18 feet, though wells are sometimes of less depth. 



CLAY COUNTY. 

 GENERAL STATEMENT. 



Clay County is situated west of Richland and south of Effingham 

 County. It has an area of 470 square miles, with Louisville as the county 

 seat. The county is traversed by the Little Wabash River nearly centrally 

 in a northwest to southeast course. The greater portion is directly tributary 

 to this stream, but a narrow strip on the western border is tributary to 

 Skillett Fork, a stream which enters the Little Wabash near its mouth. This 

 county, like the neighboring counties just discussed, has a coating of white 

 clay several feet in depth, which is very slowly pervious to water. The 

 streams, however, are bordered by broad bottoms with looser and more 

 fertile soil. 



The drift on the uplands is usually but 15 to 30 feet in depth. Wells 

 are in many cases obtained in the drift, but a large number penetrate the 

 underlving rock a few feet. The drift along the streams is probably of 



