WELLS OF MONTGOMERY COUNTY, ILLINOIS. 741 



Rock is often entered at 50 to 75 feet, and is exposed along- the streams at 

 a similar level below the upland plain. Occasionally the thickness of the 

 drift is but 10 or 20 feet, as at Harvel and Witt, noted below. 



INDIVIDUAL WELLS. 



At Thomasville, in the extreme north part of the county, the wells 

 enter rock at a depth of about 30 feet, but are usually obtained near the 

 base of the drift. At Harvel rock is entered at 14 to 20 feet. 



At Nokomis, in the eastern part of the county, the drift is about 100 

 feet in depth. The Manual of American Waterworks reports that the public 

 water supply is obtained from driven wells, but the depth is not given. In 

 the vicinity of Witt, a few miles south of Nokomis, rock is entered at about 

 10 feet, but wells are obtained without difficulty near the top of the rock. 



At Hillsboro the public water supply is obtained from springs. Wells 

 are usually obtained at depths of 18 to 25 feet just above the blue till. 

 They occasionally reach a depth of 60 feet. A coal boring made near this 

 city shows a complex series of drift beds, as follows: 



Section of coal boring near Hillsboro, Illinois, 



Feet. 



Pale silt and pebbly brown clay 14 



Bluish-gray till - 23 



Sand 1 



Blue-gray till 16 



Yellow clay - 7 



Sand and gravel 20 



Blue till 26 



Sand and gravel - - - - - - 16 



Total drift 123 



Iii the vicinit}^ of Butler rock is struck at about 50 feet and the drift 

 is mainly till. Wells are usually obtained at 20 feet or less. 



The city of Litchfield obtains its public water supply from Shoal 

 Creek. A coal boring at this city penetrated 75 feet of drift. Wells are 

 usually obtained at 25 to 40 feet. About 14 miles southeast of Litchfield 

 several deep wells have been drilled for oil, a small quantity of oil being- 

 obtained at about 675 feet. The drift at these wells is 52 to 60 feet, and 

 mainly a hard blue till. 



On the plane tracts in the southeastern • part of the county wells are 

 usually obtained at about 15 feet just above the blue till. On neighboring 



