102 GUIDEBOOK OF THE WESTERN UNITED STATES. 
rounds the lakes that fill the depression once occupied by the ice. 
The gravel brought down by this glacier contains considerable gold, 
and it has been washed extensively along the river by hydraulic 
methods and by dredges. The washed gravel now lies in great heaps 
and ridges that greatly disfigure the landscape. 
The railroad emerges from the canyon a short distance beyond 
milepost 262, and the traveler finds that the valley above this point 
consists of flat, marshy ground which extends nearly to the head of 
the stream below Tennessee Pass. This upper part of the valley is 
probably in the same condition as the lower valley was ages ago, 
before the stream had cut its present canyon, and at a time when 
it was flowing at the top of the uppermost terrace that the traveler 
has seen. At that time the lower part of the valley was filled to a 
great depth with sand and gravel, and all the former inequalities in 
the surface were obliterated. The upper valley appears to be in that 
stage to-day. It has doubtless been filled with sand and gravel 
brought down from the ranges on either side until almost all the 
inequalities of the bedrock have been concealed, and on this level! 
floor the stream meanders, not exactly sluggishly, for there is con- 
siderable slope to the surface, but the quantity of loose material 
furnished to the stream is much more than it can carry away, so 
that it is being continually dropped and thus obstructs the channel of 
the stream and forces it to shift its course to one less direct. If 
conditions were changed so that Arkansas River had a sharper 
descent or a greater volume of water, it would have more cutting 
power, and it would then soon trench this flat bottom, and the cut 
edges of the valley filling would stand up as terraces just as the 
terraces stand above the stream lower down. 
On emerging from the canyon the traveler again has an unob- 
structed view of the mountain range on the west, and its aspect is 
very different from the view which he had below Riverside. The two 
’ most prominent peaks visible from the upper end of the canyon are 
Mount Elbert, which stands just above the moraines of Lake Creek, 
and Mount Massive, which stands farther up the range. 
The altitude of the valley is so great that few plants except grass 
can be grown to advantage, but the hay crop is luxuriant, and stock 
raising is the principal business. As the train departs more and more 
from ‘the great moraines that bound Lake Creek on both sides the 
mountain peaks back near the head of the creek come into view. 
These peaks are more rugged than most of those that have been in 
sight from the railroad. The accompanying sketch (fig. 24) shows 
the most prominent peaks that can be seen from milepost 265 by one 
looking to the southwest. These peaks all appear to the left of Mount 
Elbert, some of them showing from behind the projecting spurs of 
that mountain. La Plata Peak (14,332 feet) appears in the center, 
