SURFACE FEATURES. 67 



base of its valley-sides, the Lower Magnesian limestone 

 forming the remainder of them. The greater part of the 

 portion which traverses Winneshiek county, has its sides 

 composed almost entirely of strata of the age of the Trenton 

 limestone, which has a thickness in this part of the State 

 of not less than two hundred feet. In the lower part of the 

 valley the flood-plain sometimes reaches a width sufficient for 

 the location of small farms; but usually the valley is too 

 narrow for such purposes, and is often without any flood- 

 plain at all. The valley sides are almost everywhere high 

 and steep, and cliffs of Lower Magnesian and Trenton lime- 

 stones often give them a wild and rugged aspect. 



The farming lands of the higher surface, however, extend 

 almost to the very verge of the valley, so that in most cases 

 as soon as one leaves the valley in any direction, he comes 

 immediately upon a cultivated country. This stream has the 

 greatest slope per mile of any in the State; consequently 

 it furnishes immense water-power. This is particularly the 

 case with that portion of it which traverses Winneshiek 

 county. In this county especially, the valley is very beauti- 

 ful and picturesque. In some places, as for example where 

 creeks come into it, the valley widens and affords good 

 locations for farms and villages. The town of Decorah is 

 located in one of these widened parts of the valley which 

 makes it a lovely location and the almost unlimited water- 

 power of the river and smaller spring- streams around it, 

 offer fine facilities for manufacturing and for fish-culture. 

 This river and its tributaries are the only trout streams in 

 the State. 



The Mississippi river. It seems almost like mockery to 

 pass over this grand old river with so few remarks as are 

 here devoted to it, but the object of this chapter is only to 

 describe the general surface features of the State. Therefore, 

 only a very brief outline of the character of that portion of 

 its valley which borders upon Iowa can be given here. This 

 may be described in general terms as a broad canal cut 

 out of the general level of the country through which the 



