DIVISIONS OF THE D I S T R 1 C T. 



215 



milion Rivers on the west, the United States boundary line on the east and north- 

 east, and Lake Superior — from the mouth of Pigeon River to Fond du Lac — on the 

 south and southeast. 



The first division is based on magnesian limestone, has a good soil, and is covered 

 with vegetation. Throughout its whole extent the surface is undulating, with few 

 high hills or deep valleys, and is about three-fourths prairie land. Within its 

 limits are included the mouths of the Wisconsin, Bad Axe, Prairie a la Crosse, 

 Black, Mountain Island, Chippewa, Rush, Buffalo, and St. Croix Rivers. It is well 

 watered by branches of those streams, and many smaller tributaries of the Missis- 

 sippi. It contains few lakes, or large ponds, until it crosses St. Croix River, when 

 they rapidly increase in number, and marshes and wet meadows are frequently met 

 with. In this section, also, springs occur. Some of them are, no doubt, the outlets 

 of lakes on the neighbouring highlands, and afford a large and constant supply of 

 water. At several points advantage has been taken of the elevation of their source 

 above the river-level, and the streams flowing from them have been applied to 

 manufacturing purposes. 



The second division embraces a section of country made up almost entirely of 

 barren sands, the debris of the lower sandstone of Wisconsin, with occasional patches 

 of drift from more northern regions. It is generally " rolling," or rises in steppes 

 from the margins of the rivers which pass through it, to the height of forty and one 

 hundred and fifty feet above the water-level. It supports, at intervals, thin clumps 

 of stunted trees, and a few short coarse grasses. Along the borders of some of the 

 streams, however, occasional patches of a better sort of vegetation occur. While 

 this division affords a passage for the rivers which rise in the highlands of the thin 1 

 division, few or no streams have their origin in it, the sands absorbing the rains as 

 they fall, and thus preventing their accumulation into streams. 



The loose sands, which are of great depth in many sections, are easily acted upon 

 by prevailing winds, and give rise, by their shifting, to constant local changes of 

 level. Along the banks of the rivers a great number of sections were observed, 

 showing a line of former vegetation, now covered by from ten to twenty-five feet of 

 sand. These circumstances must always render the sandy district barren. Whether 

 the sands are likely to encroach upon the present arable lands, to any serious extent, 

 is a question of great moment, and one which will require a long series of observa- 

 tions for its solution. 



The third division differs widely, in many respects, from the preceding ones. 

 Throughout a great portion of it, south of the water-shed, crystalline and metamor- 

 phic rocks either show themselves in the slopes of the hills or form the beds of the 

 streams, underlying the soil and drift ; while north of the ridge which divides the 

 waters of Lake Superior from those of the Mississippi, they either come to the sur- 

 face, or are met with under the marls and sandstones of that region. 



The water-shed is formed by a series of hilly ranges, which, on the south side, 

 commence at an average distance of forty to sixty miles from the Mississippi, and 

 form successively the falls and rapids of all the rivers above the northeast boundary 

 of the first division, as well as of the small streams tributary to them. The ascent 

 is, at every point where observations were made, very gradual, and, occasionally, 



