50 GEOLOGICAL SURVEY OP WISCONSIN. 



REGISTER OF THE ARTESIAN WELL IN THE CAPITOL PARK, MADISON. 



926 

 918 



858 

 846 

 829 

 824 

 804 

 800 



745 



671 



661 

 166 



131 

 122 

 1201 



98 



Top of well . . 

 Sou and clay. 



DBIFT. 



Sand and boulders 



Gravel 



Clay and laminated rock 



Grayish-brown rock (boulder?). 

 Indurated clay (quite compact) . 

 Rock (boulder?) 



POTSDAM SANDSTONE.* 



Sandstone gravel, quite loose, white and yellow, no ce- 

 ment or coherence 



Loose, white, uncemented sand, with layers of yellow 

 sand 



Bottom of tubing 



White sandrock, grains sharp, but always somewhat 

 rounded, with occasional layers of grayish color, the 

 whole cemented sufficiently to preserve the sides of 

 the well. Sample from 700 feet below surface showed 

 under microscope very much rounded grains of Hmp- 

 id quartz, some perfectly pure, some stained in spots 

 with oxide of iron _ 



White quartz sandrock of finer grain, mixed with a sub- 

 stance resembling porcelain 



Red clay-like powder, very slightly gritty, under high- 

 est X)Ower appears to be mostly very fine quartz sand. 



Coarse, dark, reddish-brown powder, mostly very much 

 rounded quartz grains, but mingled with some dark, 

 opaque grains also rounded, belonging therefore with 

 the mechanical rocks 



I 



AEOHiEAN. 



Dark grayish mixed rock, very hard to drill, coming up 

 in quite large fragments all angular; carries patches 

 of a greenish cleavable mineral; sp. gr. of rock, 2.76; 

 hardness, 5 ; fuses at about 8 to a black bead. Tlie 

 included mineral (prehnite) is cleavable and semi- 

 tran.slucent, and fusible at 3.5 to 4 to a white enamel. 



Crystalline rocks (work suspended) 



60 

 12 

 17 



5 

 20 



4 



55 



74 

 10 



495 



35 



9 



i'A 



2'-'i.^ 



187 



Co 



P 



III 



80 



97 



102 



122 



126 



181 



255 

 205 



760 

 795 

 804 



805M 



828 

 1015 



348 

 340 



280 

 268 

 251 

 246 

 226 

 222 



167 



93 



83 



—412 

 —447 

 -456 



—480 

 —667 



The numerous artesian, wells, though not always successful in 

 affording water, show very important results in regard to the rock 

 strata far beneath the surface. The recent discovery of native copper 

 and silver in the well at Kilbourn City, at the depth of 516 feet, 



* Possibly this should stand next before the gravel, depth 80 teet. 



