624 THE ILLINOIS GLACIAL LOBE. 



has an estimated capacity of 190 gallons per minute. The head is sufficient 

 to raise the water about 30 feet above the surface, or 675 feet above tide. 

 Several water veins were encountered, as follows : In the Devonian or 

 Upper Silurian limestone, at 140 to 160 feet; Galena, at 950 to 975 feet; 

 Lower Magnesian, at 1,350, 1,450, and 1,590 feet; Potsdam sandstone, at 

 2,040 to 2,160 feet. The determination of the geological horizons was 

 made by Prof. J. A. Udden, who also has furnished the other data given. 



The city of Kewanee, in the southeast part of the county, also obtains 

 its public water supply from artesian wells, two wells being 1,050 feet and 

 a third 1,480 feet in depth. The principal supply of water in all the wells 

 is probably from the St. Peter sandstone at a depth of about 1,000 feet, the 

 upper veins of water being cased out. The head is 150 feet below the 

 surface, or 700 feet above tide, this city being located on an elevated tract 

 about 850 feet above tide. The wells have a combined capacity of about 

 260 gallons per minute. The water is comparatively soft and of pleasant 

 taste. Its temperature in each well is 65° Fahr. The private wells in 

 Kewanee and vicinity are usually obtained at 40 or 50 feet from gravel 

 below till. The drift at the artesian wells is about 80 feet in depth and 

 mainly till, but at a coal shaft a half mile east of the city, at equally high 

 elevation, rock is entered at 35 feet. 



At Galva, in the southern part of the county, at about the same eleva- 

 tion as Kewanee, rock is entered at 30 to 60 feet, but many of the wells 

 obtain an abundance of water in the drift after penetrating a sheet of till. 

 The last edition (1897) of the Manual of American Waterworks reports the 

 public water supply to be from a well. At the brickyards a well has the 



following section: 



Section in brickyard at Galva,. 



Feet. 



Loess - - 15 



Black soil (Sangamon) 2 



Brown till 30 



Blue till 8 



Sandstone at bottom. 



The soil at the base of the loess is well exposed in the clay pit at the 

 brickyards. A large log was found embedded in this soil, but no speci- 

 mens were at hand at the time of the writer's visit to the locality. 



At Cambridge wells are usually obtained at about 40 feet, in gravel 

 beds below till. Occasionally a well reaches a depth of 75 feet. The drift 

 in that vicinity is about 60 feet in depth, including 15 or 20 feet of loess. 



