478 THE GLACIAL LAKE AGASSIZ. 



uortliem quarter. These rates of ascent are slightly reduced in the second 

 Norcross stage, where the total ascent is 160 feet. While the outlet was 

 being eroded probabl)' 5 feet between the Norcross stages, the combined 

 rise of the land and decline of the lake level were about 10 feet on the 

 international boundary and 25 feet on tlie latitude of Gladstone. The lake 

 shore belonging to the Tintah stage « ascends about 20, 30, 40, and 45 feet 

 in the successive distances from south to north, amounting in total to 135 

 feet; in the same distances the Campbell a shore ascends about 10, 15, 30, 

 and 35 feet, in total 90 feet; the McCauleyville a shore ascends about 7, 10, 

 20, and 28 feet, in total 65 feet; and the McCauleyville h shore ascends about 

 5, 10, 15, and 22 feet, in total 52 feet. The erosion of the River Warren 

 from the Norcross a stage to the McCauleyville h stage, at the end of which 

 the southward outflow ceased, was about 70 feet; but the vertical distance 

 between the shore-lines of these stages on the latitude of Gladstone is 

 about 200 feet, the difterence of 130 feet heing attributable to the north- 

 ward rise of the land and the fall of the lake level on account of the 

 diminished attraction of the ice-sheet. The rate of northward ascent is 

 reduced to less than an inch per mile along the southern part of the lowest 

 McCauleyville shore, and to 3 or 4 inches per mile along its northern part, 

 the average being 2 inches. 



From the time of this lowest beach, formed during the southward 

 outflow of Lake Agassiz, to the time of the first beach, formed dming its 

 northeastward outflow, the lake fell only about 15 feet. Thence there is 

 now a descent, on the latitude of Gladstone, of aboiit 220 feet to the 

 Niverville beach, below which Lake Agassiz, while its northern banier of 

 ice remained, fell about 45 feet more before it was reduced to Lake Winni- 

 peg. The northward ascent of these shore-lines of northeastward outlet 

 decreases only slightly in the distance of 75 or 80 miles examined north of 

 the international boundary, the change being approximately from 20 feet 

 to 15 feet or less — that is, to the rate of about 2 inches per mile. If these 

 stages of the lake had reached south to Lake Traverse, they would proba- 

 bly show a decrease from about 50 to 25 feet, or to 20 feet, in their total 

 northward ascent above the level of the present time along the distance of 



