364 THE GLACIAL LAKE AGASSIZ. 



1,400 feet. This ascent, forming the steep foce of tlie Pembina Mountain, 

 is made upon a widtli of about a quarter of a mile. 



Where tlie Pembina Mountain yjlatean is ascended by the Southwestern 

 Brancli of the Canadian Pacific Railway, and for a distance of about 4 

 miles south and 2 miles north of this railway, the principal line of escarp- 

 ment is replaced by a moderate slope which is chiefly prairie. Across this 

 tract the Herman beaches of Lake Agassiz are well developed. In order 

 proceeding northward, the iirst point of examination of the highest beach 

 was near William H Oakley's house, in the south edge of the southwest 

 quarter of section 2G, townsJiip 2, range 6. It is here a massive rounded 

 ridge of gravel and sand, with descent of 12 to 15 feet in a distance of as 

 many rods both to tlie east and west from its crest, which is 1,253 feet 

 above tlie sea. Northward this beach, with similar outline, extends to 

 Francis J. Parker's house, which is built on its crest, having there also a 

 height of 1,253 feet, in the north edge of the northwest quarter of this 

 section. Westward from this beach is an undulating surface of till with 

 few bowlders. Half a mile farther north the beach is intersected by the 

 deep and broad ravine of Dead Horse or Cheval Creek. Beyond this 

 ravine the beach begins near Samuel B. Bowen's house. Its elevation 1 to 

 1^ miles north-northwest of Mr. Bowen's is 1,255 to 1,259 feet, and it is 

 there spread more broadly than usual, having a nearly flat surface on a 

 width of 20 to 30 rods, bordered on the east by a descent of 10 or 15 feet 

 in 20 rods, and on the west by a descent of about 4 feet. The beach is 

 gravel and sand, with till on each side. It has nearly the same features 

 also a third of a mile farther north, near the ceilter of section 10, township 

 3, range 6, where it is crossed by the road from Morden to Thornhill, the 

 elevation of its crest l)eing 1,258 feet, but the depression on the west is 

 reduced to only 1 or 2 feet. In the same section this and lower beach 

 ridges are excavated beside the railway for ballast, and are found to consist 

 of sand and gravel, with pebbles seldom exceeding 2 or 3 inches in diame- 

 ter. Al)out half of the pebbles are light-gray magnesian limestone and 

 about half Cretaceous shale, such as forms the Pembina Mountain, with 

 only a small proportion derived from Archean rocks. Thence the highest 

 shore continues north through the east part of sections 16 and 21, township 



