THE NORTHERN PACIFIC ROUTE. 
33 
the Herman beach. It was formed when the water of Lake Agassiz 
stood at its highest level and consequently marks the line between 
the unmodified glacial topography above and the smooth surface of 
the old lake basin below. The difference in the topography may not 
be noticeable on the east side of the valley because of the unfavor- 
able outlook, but on the opposite side of the valley west of Fargo 
the difference is very striking and can readily be seen from the train. 
Between mileposts 242 and 243 the railway emerges from the now 
shallow valley of Buffalo Creek, and the traveler may obtain his 
first view of the famous Red River valley, which has been referred 
to frequently as the ‘‘granary of the world,” but which was once a 
lake about 50 miles wide at this 
gravel prevailing, including pebbles 2 to. 
4 inches in diameter. 
The development of the beaches varies 
greatly from place to place, depending 
apparently upon the abundance and 
the valley is crossed by the main line of 
the Northern Pacific Railway three beach 
ridges are clearly visible on the east side 
of the valley and two on the west. At 
Wahpeton (waw’pe-ton), on the Fergus 
Falls branch of the same road, there are 
four well-developed ridges on each side 
of the valley. At Grand Forks there are 
four ridges on the east, where they are 
crossed by the Great Northern Railway, 
and twelve on the west. Not only does 
the number of ridges vary from place 
to place, but ridges disappear and other 
ridges, either higher or lower, a i 
their places, so that the identification of 
the various ridges is a matter of consider- 
able difficulty. 
The Herman beach, which marks the 
highest stage of the lake and which is the 
one most easily recognized, has been 
traced for a long dist 1 the south 
and west sides of the lake, but the lower 
beaches are not so well marked and can 
not be traced continuously. 
Sand vel deltas, so extensive 
_as to be notable features of the topography, 
ormed by several streams tha 
flowed into the lake while it stood at its 
highest stages. The Buffalo River delta, 
down which the Northern Pacific Rail- 
95558 °—Bull. 611—15——_3. 
point and nearly 700 miles long. 
way runs immediately west of Muskoda, 
covers an area about 7 miles long from 
north to south and 2 to 33 miles wide from 
east to west. As the average thickness 
of the material laid down in this delta is 
about 50 feet, its volume is probably one- 
sixth of a cubic mile. The delta plain, 
as shown in figure 4 (p. 34), is terminated 
about 3 miles west of Muskoda by a steep 
slope, like the face of a terrace, 25 to 40 
feet high. 
The floor of this ancient lake is appar- 
ently a level plain, although it really 
has a slight slope toward the middle and 
a gentle northward inclination of about 
a foot to the mile. 
The several shore lines are not el 
with one another or with sea level, but 
all show an ascent toward the north or 
northeast. 
beach rises 17 
Traverse, the lower end of Lake Agassiz, 
and the international boundary, but the 
grade is not regular, being 35 feet in the 
first 75 miles, 60 feet in the second, and 
80 feet in the third. The lower beaches 
show a similar though less pronounced 
tise. As these beaches must have been 
horizontal when they were formed, it is 
evident that the crust of the earth has 
ence and continued for some time after it 
