BEACHES WITH NORTHEASTWARD OUTFLOW. 445 



Kettle Hill, near tlie south side of Swan Lake, separated by a vertical 

 interval of 20 feet; and the Niverville beach is subdivided into three at the 

 Grand Rapids of the Saskatchewan. Instead of the eleven or twelve shore- 

 hues observed by me in the United States and in southern Manitoba, 

 belonging to the time of northeastward outflow, Mr. Tyrrell therefore has 

 at least fourteen upon the country 150 to 200 miles farther north. 



From the following detailed descriptions of the beach deposits of these 

 lower shores it will be seen that their magnitude and the distinctness of 

 their development are very similar to those of the earlier and higher shox-es 

 foimed during the stages of southern outflow. It should be noted, how- 

 ever, that on account of the favorable surface of the lake bed in North 

 Dakota, consisting in large part of gently sloping till, they are more gener- 

 ally traceable there than on the Minnesota side of the Red River Valley, 

 where some extensive tracts, having mostly a surface of silt with smaller 

 areas of till, were traversed and cursorily examined without detecting dis- 

 tinct shore-lines. If they should be more thoroughly searched for on these 

 tracts, with leveling along their known height, as shown by their nearest 

 beaches observed elsewhere, doubtless some evidences of shore erosion or 

 deposition would be found almost continuous, though their character and 

 significance might not be otherwise recognizable with certainty; but it has 

 been impracticable to give the time for field work that would be required to 

 survey and map in this manner the exact course of these shores through 

 their whole extent. It is believed that the portions which have been 

 mapped with leveling, shown mostly on Pis. XXIII to XXXIII, inserted 

 in Chapter VI, are sufficient to show reliably the successive stages in the 

 concurrent uplifting of the land and subsidence of the lake. 



BEACHES OF THE BLANCHARD STAGES. 



Three successive levels of Lake Agassiz, or pauses in the crustal uplift 

 while the lake shore passed near Blanchard, N. Dak., seem to be indicated 

 by sand and gravel deposits which are crossed by the Duluth and Manitoba 

 Railroad 5 to 7 miles southeast of Euclid, Minn., and by the Manitoba and 

 Northwestern Railway near Midway station, Manitoba. The lowest of 

 these, however, has most definitely the form of a beach ridge, and the 



