YELLOW MEDICINE, LYON AND LINCOLN COUNTIES. 591 



Lakcs.J 



Nearly a hundred square miles in southwestern Lincoln county, lying southwest of the high- 

 est ridge of the Coteau des Prairies, are drained into the Big Sioux rirer, by Medary and Flan- 

 dreau creeks. This area includes Verdi, and parts of Shaokatan, Drammen and Lake Benton 

 townships. Its surface is a smooth expanse of till, sloping gently to the southwest, character- 

 ized by the absence of lakes, like Pipestone and Rock counties on the south, which, with this 

 tract, lie west and outside of the western and outer terminal moraine. 



Lakes. East of this outer moraine, lakes and sloughs are frequent in this district, excepting 

 the central and north parts of Yellow Medicine county. They are most abundant upon the Co- 

 teau des Prairies between its two morainic belts. The largest are lakes Benton, Shaokatan and 

 Hendricks, respectively six, three, and three and a half miles long, trending from northeast to 

 southwest, lying in Lincoln county close to the western moraine, with the description of which 

 these lakes will be noticed more fully. More than thirty other lakes, varying from a half mile 

 to one and a half miles in length, most frequently having the longer axis from north to south, 

 occur in central and southeastern Lincoln county. Among these are Eagle lake, more than a 

 mile long from northwest to southeast, crossed by the line between Royal and Limestone town- 

 ships; lake Stay, one mile long from north to south, which gives name to its township; lake 

 Nova, formerly called Dead Coon lake, one and a half miles long from north to south and half as 

 wide, in the northeast part of Marshfield; and Cottonwood lake, about a mile long from north- 

 west to southeast and a half mile wide, in the south edge of Marshfield and close north of Tyler 

 station. The basin of the last named lake was dry some fifteen years ago; in 1875 it held a lake 

 of the area mentioned and five to ten feet deep; in 1880 it it was again wholly dry, and had been 

 so for two or three years, being all hard mowing-land, yielding coarse marsh-grass and sedges, 

 with cattle pasturing there, and having a dwelling-house on the lake-bottom. These changes are 

 a register of variations in the average annual rain-fall. 



In southwestern Lyon county the continuation of this region of lakes includes Goose lake 

 and Island lake, each about three-quarters of a mile long from north to soulh, in the south part of 

 Island Lake township; lake Marguerite, more than a mile long from north to south, in the north 

 part of T. 1 1O, R. 43 ; Black Rush lake, about a mile in extent, filled with rushes, near the 

 center of Lyons; two lakes, each about a mile long, in southwestern Shelburne, near the corner 

 of the county; Rock lake and lake Yankton, each more than a mile long from north to south, in 

 Rock Lake township; Long lake, a mile long from northwest to southeast, in the south part of 

 Custer; and lake Sigel, about a half mile in diameter, in southwestern Monroe, two miles south 

 of Tracy. 



The only other lakes to be mentioned in Lyon county, are lake Marshall, one and a half 

 miles long from northwest to southeast but narrow, in the southeast part of Lake Marshall town- 

 ship; Swan and Goose lakes, crossed by the east line of the county at the east side of sections 12 

 and 1, Stanley; and Lady's Shoe, Lady's Slipper and Coltonwood lakes, each about a mile long, 

 and Sham lake, of smaller size, a mile east from the last, all situated in Lucas, the most north- 

 east township of the county. 



The greater part of Yellow Medicine county has no considerable lakes. This area probably 

 was covered by a broad and shallow expanse of water during the recession of the ice-sheet, by 

 which the surface, consisting of till, in some* parts slightly modified, was smoothed, and its hol- 

 lows that would have held lakes were filled; as the nearly flat sheet of till that forms the south- 

 ern part and the sides of the great plain of the Red river valley was smoothed by lake Agassiz at 

 this epoch. Upon the Coteau at the west end of this county occasional lakelets are found nes- 

 tled among its knolls and irregular short ridges of morainic drift; and on the moderately undu- 

 lating or rolling tract of till in the southeast part of the county are numerous lakes from a half 

 mile to one and a half miles long. These include a group of three in the central part of Nor- 

 mania; Wood and Sand lakes, each more than a mile long, and trending respectively from north- 

 east to southwest and from east to west, in Wood Lake township; Tyson's lake, a mile long from 

 east to west, in the north part of Posen; and two lakes, of irregular form, each a mile or more in 

 extent, in Echo, the eastmost, situated near the center of the township, being called the lake of 

 the Woods. 



Topography. The Minnesota valley along the northeast side of Yellow 

 Medicine county is from one to one and a half miles wide, and consists of 



