CHAPTER XIX. 



THE GEOLOGY OF BROWN AND REDWOOD COUNTIES. 



BY WARREN UPHAM. 



Situation and area. Brown and Redwood counties (plate-pages 25 and 

 26) are situated in the central part of southern Minnesota, within the basin 

 of the Minnesota river, which is their boundary on the north. New Ulm, 

 the largest town and county seat of Brown county, is 36 miles east-south- 

 east from Redwood Falls, which is the largest town and county seat of 

 Redwood county. From New Ulm northeast to Minneapolis and Saint Paul 

 is a distance, in straight course, of about 75 miles. Two tiers of counties 

 intervene between these and the south line of the state; and two counties 

 on the west divide Redwood county from Dakota. 



The area of Brown county is 616.75 square miles, or 394,720.82 acres, 

 of which 6,937.52 acres are covered by water; and the area of Redwood 

 county is 893.83 square miles, or 572.052.87 acres, of which 14,930.13 acres 

 are covered by water. 



SURFACE FEATURES. 



Natural drainage. The Minnesota river, at the north side of these coun- 

 ties, receives from them two large tributaries: the Redwood river, which 

 flows east across the north part of Redwood county and enters the Minne- 

 sota about two miles northeast of Redwood Falls; and the Cottonwood 

 (called by the Sioux the Waraju) river, which also runs easterly, crossing 

 southern Redwood county, and dividing Brown county into nearly equal 

 parts on its north and south sides, uniting with the Minnesota about one 

 and a half miles southeast of New Ulm. 



