WELLS OF KNOX COUNTY, ILLINOIS. 677 



wells in the drift are located along a valley leading westward from the town, 

 and are sunk to depths of 70 or 80 feet without entering rock. They are 

 mainly through sand, and the water rises nearly to the surface. A well was 

 sunk in 1896 to a depth of 1,226 feet, entering St. Peter sandstone at 1,060 

 feet. The well is cased to the St. Peter and the entire depth penetrated in 

 this formation is thought to be a water-yielding rock. The water has a 

 temperature of 60° F. The head is 102 feet below the surface and 635 

 feet above tide, as determined by careful measurements conducted by the 

 city engineer. The capacity is estimated at 120 gallons per minute. As 

 this is but one-eighth the amount needed by the city, the drift wells furnish 

 the greater part of the supply. It is planned to sink other deep wells in 

 order to dispense with the water from the drift, since that is not entirely 

 above suspicion of surface contamination. Many private wells in this city 

 are obtained from sand below loess and till at depths of 25 to 45 feet. The 

 drift is said to be 80 or 90 feet in depth for a distance of 5 or 6 miles north- 

 east from Gralesburg, but within a short distance in other directions rock is 

 found at much shallower depths. 



At Knoxville the public water supply is obtained from a well 1,350 

 feet in depth, which was sunk in 1896. It enters St. Peter sandstone at 

 1,180 feet and continues in that formation to the bottom. The well is 

 cased to the top of the St. Peter sandstone in order to shut out sulphurous 

 water struck at higher levels. It has an estimated capacity of 80 gallons 

 per minute. The water has a temperature of 68° F. Private wells are 

 obtained in the vicinity of Knoxville at depths of 20 to 40 feet, either near 

 the base of the drift or in the underlying Coal Measures. 



At the villages of Wataga, Oneida, and Altona coal shafts usually 

 enter rock at about 30 feet, but wells are obtained near the base of the 

 drift or only occasionally from the rock. 



At Williamsfield, in the east part of the county, wells are usually 

 obtained at shallow depths in the glacial drift, seldom exceeding 40 feet. 

 The record of a well about 1£ miles west of this village is found to show 

 85 feet of drift without entering rock. The cutting-s along the Santa Fe 

 Railway between Williamsfield and Dahinda expose a complex series of 

 sand and till beds in the descent to Spoon River. Wells on the bordering 

 uplands appear to penetrate a similar complex series. 



At Yates, in the southern portion of the county, Coal Measures shale 



