MINNESOTA owes much to the many lakes which dot 

 the landscape within her boundaries in playgrounds 

 for the vacationist, the hunter and the fisherman. 

 Their attractive shores, timbered and rock-bound, fill the 

 traveler with joy at every hand. One lake in particular, long 

 since vanished, played an important part in furthering the 

 destiny of the commonwealth in leaving behind a rich legacy 

 to man in the productive valleys, hills and prairies of Min- 

 nesota and Dakota. This was the great lake called by scien- 

 tists, Agassiz. 



When the great ice sheet which covered Minnesota, parts 

 of Dakota and Ontario, began to melt, the water from the 

 eastern and southern extremities drained off rapidly through 

 the Minnesota valley, leaving the melting ice to the westward 

 below the level of Lake Traverse, to be held back at Browns 

 Valley. As the seasons warmed and the ice wall retreated 

 northward, a lake was formed, held in by the high ground on 

 the east and west and the ice barrier. The water rising rap- 

 idly found a spillway into Big Stone lake, following the val- 

 ley of the present Minnesota river into the prehistoric Rivet 

 Warren (the name given to the valley now occupied by the 

 Minnesota) and on down the Mississippi. 



The northern shore of Lake Agassiz was the ice wall and 

 was thus continually changing its position, while the western 

 shore followed the valley line of the Red river on the west- 

 ward to swing still further west into Southern Manitoba. The 

 eastern shore lay in Traverse county and ran nearly north to 

 Maple lake, turning further east here to pass south of Red 

 lake, entirely across Itasca county in an irregular course, 

 then running northwest into Ontario, taking Rainy lake and 

 several existing lakes to the east within its boundaries. This 

 great body of water at its greatest development covered about 

 one hundred and ten thousand square miles, an area larger 

 than all the Great Lakes, but in spite of its great expanse, the 



