248 The American Geologist. ,V|.rii, 1897 
excavations, tlie ineoherent portions are found to alternate, 
botli liorizontally and vertically, with other portions in which 
the original bedding planes have been but little disturbed. 
This is characteristic of this class of phenomena, and consti- 
tutes a link between the tilted but not transported rock and 
the perfectly commingled angular deposits. One of the for- 
mer varieties is well displayed in a road cutting in this region, 
where the upper twenty feet of the limestone in situ has been 
folded by the pressure of the ice applied from the northeast. 
This fold shows dips of 80°, and the strata near the surface 
are somewhat broken. Of the many deposits in which the 
material has unquestionably been transported from the parent 
ledges. I will describe a few of the most significant. 
6. In the center of a small valley two miles west of Dakota, 
there stands a single cone-shaped mound about 30 feet high. 
It is composed of Galena limestone, not much broken, but with 
the strata dipping steeply in every direction from the center 
and top of the mound. Burrowing animals bring out water- 
worn drift gravel and sand from under the limestone at the 
base of the mound. 
7. Three miles west of the village of Dakota, there is a short 
ridge of broken limestone, standing in and nearly obstructing 
a deep valley. This ridge trends east and west, and is per- 
haps 75 feet high. Angular pieces of Galena limestone are 
exposed all over the surface, except at the base, where bur- 
rowing animals, as in the former case, bring out waterworn 
gravel and sand, 
8. Three miles southwest of Dakota, the Chicago, Milwau- 
kee & St. Paul railway passes a high rock ridge, making a 
long deep cut into the Galena limestone. On the western side 
of this ridge, both north and south of the railwaj^ there are 
huge piles of broken limestone, which, at first sight, might be 
confounded with the similarly shaped masses which were tak- 
en out of the rock cutting and piled up. However, the amount 
of the material, the distance from the railroad, and the fact 
that a line of these knolls extends thence northwestward for 
a long distance, must soon convince the observer that these 
deposits of angular gravel are a natural formation. 
In discussing the significance of these accumulations of 
angular local limestone debris, I wish to call attention to cer- 
tain features which are common to all of them. 
