24 



THE GLACIAL LAKE AGASSIZ. 



300 feet in the next 19 miles to 1,162 feet above sea-level at the highest 

 beach of Lake Agassiz, 4J miles west of Larimore. The westward ascent 

 continues to 1,525 feet above the sea 12 miles west of this beach. 



At St. Vincent and Pembina, near the international boundary, which is 

 224 miles north of Lake Traverse, the surface of the plain is 785 to 790 

 feet above the sea (fig. 5). Eastward on the boundary it is nearly level, 

 rising only a few feet in the first 10 miles. Thence an ascent of about 50 

 feet is made in 2 miles to the crest of a slight ridge. Farther east the 

 countr}^ is wooded, and many extensive tracts are tamarack swamps. The 

 Lake of the Woods, about 85 miles east from the Red River, is 1,060 feet 

 above the sea; and the highest land near the international boundary west 

 of this lake is approximately 1,090 feet. Continuing eastward along the 



isoo 



Fig. 5.— Sectii 



( the Red River Valley on the international boundary, 

 an inch ; vertical scale, 1,000 feet to an inch. 



Horizontal scale, 20 miles to 



boundary, ^\'hich here is formed by the Rainy River and Rainy Lake, the 

 elevation of the highest beach of Lake Agassiz is reached a short distance 

 east from the east end of Rainy Lake, more than 200 miles from the Red 

 River. Westward the surface rises about 40 feet in 15 miles from Pembina 

 to Neche, and 187 feet in the next 21 miles along the international 

 boundary to the base of the great Cretaceous escai-pment called Pembina 

 Mountain, which, within 2 miles farther west, ascends nearly 400 feet to 

 an elevation approximately 1,400 feet above the sea. 



These sections give a good idea of the average width and elevation of 

 the flat plain to which the name Red River Valley seems to be properly 

 limited, both by topographic features and by the common usage of this 

 term. At a distance of 35 miles north of Lake Traverse its width is about 



