162 GEOLOGY OF EASTERN WISCONSIN. 



These may be distributed as follows: 



The flow is derived from the St. Peters sandstone. It cannot have 

 its source in that formation directly to the west, since the outcrop is 

 lower than the surface of the well. The fountain head is probably 

 in the same region as that of the "Watertown wells of its class. I was 

 told that originally the stream was very large, and could be raised 30 

 feet above the surface, but at the time of my visit it was meager, and 

 would rise less than four feet. Whether this was due tcf defective 

 tubing, as was claimed, could not be ascertained. 



The flowing wells at Whitewater are confined to the drift, and owe 

 their origin to the fact that a bed of lacustrine clay rests upon the 

 flank of drift hills to the southeast, that are admirably adapted to 

 serve as collecting areas. The well of Mr. P. Dorr is 52 feet deep in 

 a stiff blue clay. Its flow is copious and is charged with iron and 

 sulphuretted hydrogen. 



The number of these wells may be somewhat increased in all prob 

 ability, but the limited extent of the clay deposit will confine then" 

 to the localities occupied by it. 



The surface of the Niagara limestone at Manitowoc is thickly 

 covered by impervious drift, and the strata beneath rise to the west- 

 ward, and are partially permeable to water, so that the requisite 

 conditions for a flowing well are found at no great distance within 

 the limestone, if the boring is fortunate in striking a suitable vein. 

 At the well of Mr. "William Rahn, the drift is sixty feet deep and the 

 rock was penetrated ninety feet. The wells at Washington Park and 

 at Woodman's Tannery are given as about the same. An analysis of 

 the water of Mr. Rahn's well is given in the report of Dr. Lapham, 

 in this volume, ante, p, 31. 



The following section of the well at Western Union Junction 

 is prepared from data furnished my predecessor by John C. Gault, 

 from the general manager's office of the Milwaukee & St. Paul Rail- 

 way Company, to whom the well belongs. This and the following 

 are of especial interest as giving, at a point so near the southeast cor- 

 ner of the state, the thickness of several of the formations, and as 

 furnishing data for the reliable estimate of dip, and for other cal- 

 culations: 



