Geology of the Region About DeviV s Lake. 127 



turrets and towers, making one of tlie most cliarming bits of 

 landscape in our state. 



Change in Course and Bed of Baraboo Eiver. — A 

 word in evidence that tlie Baraboo river formerly ran through 

 the valley and was turned aside by the glacier drift. The 

 surface of the lake is thirty feet above the court house at Bar- 

 aboo, and one hundred and sixty feet above the Wisconsin 

 river to the south. (These figures are Mr. Canfield's.) The 

 lake is more than thirty feet deep and has a bottom of sand- 

 There is therefore a sufficient descent. The valley is a natu- 

 ral course for the river, and running water would have given 

 it some of the features of its present form. In the valley, both 

 north and south of the lake, there is an abundance of drift. 

 In a few hours a large variety of northern rocks was collected, 

 granite, syenite and Lake Superior rocks. They, with sand, 

 have filled up a deeper valley to such a height that the river 

 finds a new course to the Wisconsin. 



There is another point of great interest in this region, which 

 does not appear to be easy of solution. On the top of the 

 ridge and in lines running north and south are conglomerated 

 boulders. These are local and do not extend far to the south 

 of the southern ridge. They consist of rounded, water- worn 

 pebbles, and large boulders of quartzite imbedded in a friable 

 sandstone. Some of these conglomerated boulders weigh many 

 tons. They are evidently deposited at a very little distance 

 from the place of their origin. Evidently, in this immediate 

 neighborhood, pieces of quartzite have been for a long time 

 subjected to running water, and have found themselves in a 

 bed of sand, which has been hardened, and some moving 

 cause has carried them into their present positions. The place 

 and time and agencies which have produced these effects, 

 demand a more careful and close study, such as it is the object 

 of the Academy to encourage. There are also signs of a sec- 



