STUDIES IN THE DRIFTLESS REGION OF WISCON- 

 SIN II. 1 



Since my article which appeared in the November-December 

 number of the Journal of Geology was written, much additional 

 evidence has accumulated, largely along new and supplementary 

 lines. There have, however, been some additions along the 

 lines there developed, which I beg to notice in an extended 

 footnote. 2 



1 On page 834 of my last article a change in the paragraphing somewhat obscured 

 the course of the reasoning. The objections to torrential action were grouped under 

 three heads : a, transverse ridges, beginning at the tenth line from the top ; b, the 

 lateral ridges ; c, the size of the material. 



The first head was improperly made to begin at the twenty-third line from the top, 

 where there is only a reference to the ridge, b, Fig. 1. I think that I was myself partly 

 the occasion of the mistake, since the b stood alone, Fig. 1 having been omitted. The 

 third head should have been worded more in harmony with the others and more 

 indicative of its own character. 



2 Regarding the ridge d (Fig. 1 of last article) I stated that it seems to belong 

 structurally to both valleys. But the heavy masses of ferruginous sandstone which 

 form so conspicuous a component of the ridge appear to be peculiar to the east valley. 

 The knob d (Fig. 1) is composed of it. It also occurs on the north rim at c (Fig. 7). 

 Although much harder than the sandstone in the same horizon on either side, it is 

 not as prominent in the topography as we should have expected, owing probably to 

 the fact that it has pronounced joint structure and the separate masses are rather 

 easily dislodged. The supposed bowlder bed on the west side of the west valley 

 (shown in gully) is of small material, undoubtedly a water deposit, leaving the ridge 

 b (Fig. 1) as the terminal deposit for that valley. 



An interesting feature has developed in connection with the ridge shown in Sec. 

 4, Fig. 2 of last article, occurring in the third valley described (position shown at c, 

 Fig. 4). A well dug just in front of the line of the section struck at once into a clay 

 resembling the loess and entirely free from stones. It continued in this for its entire 

 depth, about twenty feet. 



The terminal arrangements of the material in the last valley described (partly 

 shown in Sec. 6, Fig. 2) displays a certain feature which claims further notice ; an 

 independence of the minor features of the topography, shown in the direction of 

 movement and the disposition of the beds. In the accompanying figure I have 

 represented by contour lines the original rock surface and by dots the contour of the 

 lower end of the beds. The axis of the old valley runs very close under the eastern 

 hill, while on the west a broad shelf rises gradually toward the nearest bluff. 



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