DENVER & RIO GRANDE WESTERN ROUTE. 119 



result is that the quartzite steadily approaches railroad level do^vn- 

 stream. About half a mile below milepost 297 the quartzite reaches 

 railroad grade, and a short distance below it passes beneath the 

 stream and is lost to view. 



Just before reaching Kex siding the traveler may see on the west 

 (left) a ridge of loose boulders, which seems almost like a dam 

 thrown across the valley of Eagle River. Doubtless he has already 

 learned to recognize such an accumulation of boulders as a moraine 

 that was pushed out by a glacier from some side valley. This moraine 

 was built by a large body of ice which descended Cross Creek from 

 the high peaks of the Holy Cross group of mountains. The boulders 

 were carried entirely across the valley of Eagle River, showing that 

 the ice filled the valley to the foot of the slope on the east side. The 

 glacier exparrded when it reached Eagle River, so that its extremity 

 must have resembled a fan, and it coA^ered the area on which the rail- 

 road has been built for a distance of 2^ miles. One of the great blocks 

 of gneiss which it carried to the foot of the slope on the farther side 

 may be seen on the east (right) of the track near Elk Creek. It 

 is 40 feet long and 25 or 30 feet wide, and its top stands 12 feet aboA'e 

 the ground. 



Cross Creek is noted for the peculiar forms that were produced 

 along it by the passage of the glacier over its granite bed. As the 

 glacier found the floor of the granite canyon somewhat irregular its 

 principal work was to round off and polish the projecting loiobs. 

 The rounded masses of granite in this canyon, called " roches mouton- 

 nees*' (rosh moo-ton-nay'), are shown in Plate LV, ^1. This name 

 has been applied by French geologists to such rounded rocks on 

 account of their fancied resemblance, when seen at a distance, to the 

 backs of sheep. 



At Rex siding the top of the quartzite is at railroad level, and the 

 Leadville limestone may be seen on the left, where it forms several 

 knobs. Its color is light blue, and it is easily distinguishable from 

 the quartzite, which has a yellowish tone. As the railroad swings 

 to the east and the rocks dip in the same direction the Leadville 

 limestone soon disappears below the bottom of the valle^'^, and the 

 only hard rocks in sight are the Carboniferous sandstones and shales, 

 which give to the slopes on the east (right) their banded appearance. 



One of the most noteworthy features of this part of the Denver & 

 Rio Grande Western Railroad is the Mount of the Holy Cross 

 (PI. LIII). This peak stands near the head of Cross Creek, but 

 unfortunately no good view of it can be obtained from the train. 

 Near the mouth of Elk Creek, however, a fleeting glimpse of 

 the mountain may be had, if the traveler is on the alert and looks in 

 the right direction. As the train swings eastward and approaches 



