136 
TOPOGRAPHY AND FLORAL DISTRICTS. 
As can be seen from the map, the route of our travel closely resem- 
bles a figure 8, the side of the figure following the Middle Loup River 
and its tributary, the Dismal, the ends and the cross at the middle 
traversing the sand hills. We also crossed the eastern half some- 
what diagonally between Plummer Ford and Thedford. The region is 
divisible into five districts, each of which was traversed by our route: 
1. Middle Loup Valley. 
2. Dismal River Valley. 
3. Sand hills of Thomas County, a barren sand-hill region. 
4, Sand hills of Hooker County, a dry valley sand-hill region. 
5. Sand hills of Grant County, a wet valley sand-hill region. 
MIDDLE LOUP VALLEY. 
The Middle Loup River is here a very swift stream, but without any 
true waterfalls. The slope of the valley, deduced from the altitude of 
the railroad at the stations, is, in Thomas County, between Seneca 
and Halsey, on an average, over 1.5 meters per kilometer, or 84 feet to the 
mile. In Hooker County it is still greater, perhaps a little less than 
2.5 meters per kilometer, or 13 feet to the mile. The fall of the river is 
perhaps only one-third or one-half as much, as the stream winds from 
one side of the valley to the other. Im Thomas County the valley is 
from 1.3 to 4 kilometers, or from one-half to 14 miles, wide and consists 
of rich meadow land. The soil in the whole region is, as a rule, sandy. 
The sand hills rise about 60 to 100 meters (200 to 300 feet), or sometimes 
higher, over the valley. North of Mullen, in Hooker County, the 
valley is much narrower, the river still more winding, and the bottom 
filled with lagoons and swamps—remains of old river beds. The val- 
ley here makes good pasture land, but is usually too rough for meadow. 
Still higher, especially above the forks, the valley is narrower yet, and 
the bottom land has almost disappeared. 
DISMAL RIVER VALLEY. 
Dismal River closely resembles the Middle Loup, but is a smaller 
stream. About 400 or 500 meters above the junction of the two forks 
of Dismal River each has a fall 3.5 or 4 meters in height. The ledge 
over which the water falls is not of a rocky, but rather of a clayey, 
formation. It is easily eut by a knife and crumbles when dried. The 
valley of Dismal River is much narrower than that of the Middle Loup, 
while the river is more winding, and here and there makes deep cuts 
(sometimes 100 meters deep) into the surrounding sand hills. The trail. 
we followed left the valley at several places on account of these cuts 
and ran over ridges 100 meters high or followed dry valleys running 
parallel with the river. We were compelled to ford the river three 
times within a space of 10 miles. The valley of the lower Dismal 
River—for instance, south of Thedford—is swampy and resembles that 
of the Middle Loup at Mullen. Farther up the stream, especially on 
