10 THE LIFE OF DEVILS LAKE 



two of which have been described by Simpson, one from what is 

 now Ft. Totten Bay and the other from Minnewaukan Bay. Indi- 

 cations of such a barrier are a small moraine extending north and 

 south across the divide between Devils and Stump Lakes and the 

 existence of "small cliffs and wave-cut terraces at elevations of 7 

 to 20 feet above the level of the A beach . . . The evidence of 

 earlier stages . . . are, however, fragmentary and inconclusive 

 . . . The life history of such must necessarily have been brief 

 and unimportant. ' ' 



The first definite shore line, or A beach, marks the lake level 

 when the outlet from what is now Stump Lake to the Sheyenne 

 River existed, and marks a level of 445 m. above the sea, and 12 m. 

 above the present surface. During the existence of this outlet the 

 water surface was evidently held approximately level for many 

 3-ears, as is attested by the distinct bluff which was formed by 

 wave action at various points, (plates 3 and 4). At other points 

 well marked beaches were formetl by the deposition of sand and 

 gravel by waves, with the occasional addition of boulders, due un- 

 doubtedly to ice shove. That this latter has played an important 

 part in developing the shores of the lake is evidenced further by the 

 boulder piles in the main section of Devils Lake known as Bird 

 Island and the Rock Pile, (plate 5) and similar islands in Stump 

 Lake, which show evidence of ice work, and by the frequent de- 

 struction or displacement of piers and boat houses in spring. At 

 this time the melting ice, driven before the fierce winds which 

 characteristically sweep these prairies, is frequently piled to heights 

 of 2 to 3 m., and must exert a tremendous pressure against the 

 shores (plate 4). 



With the loss of the supply from Lakes Saskatchewan and 

 Souris, the outlet of Lake Minnewaukan into the Sheyenne River 

 was cut off and the lake dropped from the level of the A beach 

 to that of the B, 2 m. lower, marking the period previous to its 

 separation into Stump and Devils Lakes. That the level of the 

 lake remained approximately constant for many j^ears at this period 

 is shown by the well marked cliffs and beaches developed at this 

 time. In some places indeed the B cliff was so far developed as 

 to undermine and destroy the preceding A cliff (plate 4). Tem- 

 porary periods of rise and fall between the A and B stages are in- 

 dicated by minor bluffs and beaches between these. 



According to Upham (1895) the elevation of Devils Lake was 

 441 m. about 1830, while traditions telling of the existence of certain 

 islands as late as 1867 indicate that this level was maintained up to 

 about the latter date. The later levels (C, D, & E) are poorly 

 marked, only rarely developing small bluffs, the most recent tem- 

 porary levels being indicated chiefly by zones of plants along the 



