416 THE GEOLOGY OF MINNESOTA. 



[Top.gr.phy. 



nearly level, slightly undulating expanse, with mostly imperceptible slopes, 

 which give direction to its streams. These at first flowed upon the general 

 surface, 50 to 200 feet above the valleys, now enclosed by steep bluffs, which 

 these streams by their long-continued wearing have excavated. 



About three miles above its mouth the Blue Earth river receives from the east a tributary 

 of nearly equal size with itself, namely, the Le Sueur river. This also has two large tributaries, 

 the Maple and Big Cobb rivers, which unite with the Le Sueur from the south, respectively four 

 and five miles above its junction with the Blue Earth. On its west side the only important trib- 

 utary that the Blue Earth receives in this county, is the Watonwan river, which has its mouth 

 about two miles above Rapidan Rapids, and includes within its basin of drainage all of Waton- 

 wan county and parts of the adjoining counties. Perch creek in Ceresco township, is a consider- 

 able tributary to the Watonwan from the south. 



Above the mouth of Blue Earth river, the Minnesota in this county receives three other 

 tributaries worthy of mention: Lyons or Minneopa creek, which forms the picturesque Minneopa 

 falls; and Morgan creek and the Little Cottonwood river, which have their mouths about a half 

 mile apart in section 16, Cambria, the most northwestern township of the county. 



Lakes, Many lakes occur in this county, of which the largest are as follows: lake Wita, in 

 the east part of Lime, having a length of one and a half miles and an area of about one square 

 mile; lake Ballantyne, and Duck and Gilfillan lakes, in Jamestown, each about a mile long; lake 

 Madison and Eagle lake, at the north side of Le Ray, each about three miles long and covering 

 two square miles; lake Alice and Indian lake, each about a half mile long, in the southeast part 

 of Le Ray; Rice lake, one and a half miles long, in southwestern McPhersou; Perch lake at the 

 west side of Medo, and Cottonwood lake in the southwest part of this township, each about two- 

 thirds of a mile long; Rogers lake, of similar size, at the west side of Danville; Lura lake and lake 

 Jackson, in Sterling, the former three and a half miles long, reaching south into the edge of 

 Faribault county, and the latter about two miles long and from a half to one mile wide; a 

 series of four lakes in the north part of Garden City township and the south edge of Judson, 

 namely, in their order from southeast to northwest, Mills lake, Loon lake, Crystal lake, and lake 

 Lily, of which the third is the largest, being one and a half miles long and from two-thirds to one 

 mile wide; and Dackins, Stram, and Solberg lakes, the last, which is the largest, having an area 

 of about a square mile, in Butternut Valley. 



Nicollet named the area drained by the Blue Earth river (which he called the Mankato 

 river) and its tributaries the Undine region, because of its great number of streams, " spreading 

 themselves out in the shape of a fan," its numerous lakes surrounded by woods, and its wide, 

 fertile prairies. The name was "derived from that of an interesting and romantic German tale, 

 the heroine of which belonged to the extensive race of water-spirits living in the brooks and rivers 

 and lakes, whose father was a mighty prince. She was, moreover, the niece of a great brook (the 

 Mankato) who lived in the midst of forests, and was beloved by all the many great streams of the 

 surrounding country."* 



Topography. Nearly all of Blue Earth county has a smooth and flat or 

 only slightly undulating surface; but this is deeply channeled along the 

 river-courses. The south half of the county contains two small tracts of 

 rolling land, in the northwest part of Sterling, and in the southeast of 

 Pleasant Mound. In general, the northeast and northwest parts of the 

 county are the most undulating. The Minnesota river at the north occu- 

 pies a valley 200 to 225 feet below the general surface; and the Blue Earth 



For Nicollct'i dworlptien of thiit region, see page 71. 



