650 THE ILLINOIS GLACIAL LOBE. 



surface, and that wells to a distance of nearly one-half mile are perceptibly 

 lowered by heavy draughts on any one well. Many other artesian wells 

 are made within the limits of the city and the rock strata are drained to 

 about their fullest capacity. A well at the Joliet Steel Mill reaches a depth 

 of 2,076 feet, and one at the State Penitentiary a depth of 1,948 feet, both 

 terminating in Potsdam sandstone. Another well at the penitentiary is but 

 553 feet in depth and obtains its supply probably from the Galena limestone. 



Artesian wells are obtained at Lockport, but ho data have been collected. 

 There are also artesian wells at Wilmington and Braidwood, and an artesian 

 well has been sunk on the farm of Judge Caton, about 8 miles west of 

 Joliet. The Braidwood well was made with a diamond drill, and the care- 

 fully preserved core formed an interesting exhibit at the World's Fair in 

 Chicago, in 1893. The depth is 900 feet, but the main supply of water is 

 from a porous sandstone at 655 to 855 feet, the lower 45 feet being in a lime- 

 stone with green shale interbedded. The well formerly overflowed, but at 

 present stands near the level of the well mouth (588 feet above tide). The 

 water is slightly sulphurous, but not of unpleasant taste. 



At Wilmington the best supply of artesian water is obtained at a depth 

 of about 600 to 635 feet, though in some cases strong water veins are struck 

 at 100 feet and several wells obtain water at 250 to 450 feet, The head at 

 these wells is about the same as at Braidwood, slightly below 600 feet 

 above tide. 



The following table of wells on the Valparaiso morainic system includes 

 the deepest of which records were obtained. The sections begin near the 

 State line and proceed westward and northward across the county. 



Wells on the Valparaiso morainic system in- Will County. 



Owner or location. 



Feet. Feel. 



Between Goodnow anil State J 750 100 ! Several wellB 50 to 100 feet; mainly till; no rock 



line. encountered. 



Endor and vicinity 685 75 Drift, mainly till, 75 feet; rock near bottom. 



3 miles east of Crete 725 40 Eock entered at 40 feet, 



Crest of moraine south of 750 130 No rock struck. 



Crete. 

 Crete 720 80 Eock at 80 feet. Many wells from sand at 25 to 40 



feet. 



