THE HISTORY OF DEVILS LAKE, WISCONSIN 345 



ridges or " ranges," known respectively as the North Range and 

 the South Range. These are the outcropping edges of the hard 

 Baraboo quartzite formation which forms here an asymmetric 

 syncline, the north limb of which is nearly vertical and forms the 

 North Range and the south limb of which has an average dip of 

 18 and forms the broader and higher South Range. The ranges 

 are 24 miles long in a general east-west direction, and they converge 

 at either end. The South Range is distinctly flat at and near 

 the top, the plain summit areas lying between 1,400 and 1,480 feet 

 A.T. There are also smaller areas of flattish land at 1,200 feet, 

 400 feet below Sauk Point, which is the highest point in the district, 

 and 400 feet above main drainage lines. The summit of the 

 North Range is also flattish, its evelation being about 1,200 feet. 



The district is drained by the Wisconsin and Baraboo rivers and 

 their tributaries. The Wisconsin River flows from the Dells, 17 

 miles north of Baraboo, in a broad curve past the east end of the 

 ranges at Portage to Prairie du Sac, where it may be said to leave 

 the district. Baraboo River enters the district at Ableman through 

 the North Range, in a gap known as the Upper Narrows, flows in a 

 general easterly direction between the ranges past Baraboo, cuts 

 back through the North Range at the Lower or Baraboo Narrows, 

 and joins the Wisconsin River near Portage. 



Devils Lake occupies the northern portion of the only gap there 

 is through the South Range. This gap has the form of a broad 

 open curve with a north-south course in its northern portion, an 

 east-west course in the middle of the range, and a northwest- 

 southeast course at the south edge of the range. About one-fourth 

 of the length of the gap is occupied by the lake. The surface of the 

 lake is at 960 feet A.T. which is 160 feet above the Baraboo River 

 to the north, 200 feet above the Wisconsin River to the south, and 

 about 500 feet lower than the flat top of the range east, west, and 

 southeast of it (Plate I). 



STRATIGRAPHY 



The rocks of the district about Devils Lake include the Huro- 

 nian, Cambrian, and Ordovician, each system being represented by 

 more than one formation. 



