DENVER & RIO GRANDE WESTERN ROUTE. 45 



the uplift came. At that time, owing to the fact that the rocks of 

 Pikes Peak are more resistant than those of other parts of the region, 

 the mountain stood nearly 5,000 feet above the surface of the plain, 

 just as to-day it stands nearly 5,000 feet above the surface of the 

 plateau. 



From the plateau the slopes of the mountain above appear to be 

 unscalable by a road, and it is only by constant turning and looping 

 back upon itself that the road finally reaches what appears from 

 below to be the summit but what is really a long spur of the moun- 

 tain that branches off to the northwest. The northern slope of 

 this spur, up which the traveler came, is very steep, but the opposite 

 slope is so gentle that it scarcely can be considered mountainous. 

 The difference in the appearance of the two slopes is well shown at 

 a place called " the Bottomless Pit." Here the traveler may stand 

 in his automobile and gaze down on the north into a jagged pit about 

 1,700 feet deep, whereas on the other side the slope is very gentle. 

 As the rocks are the same on both sides of the ridge there must be 

 some cause other than rock texture for this great difference in ap- 

 pearance. Geologists recognize that the steep, jagged slopes on 

 the north side are the result of the action of moving ice, but the 

 traveler may inquire : Where is the ice ? The climate here is now so 

 mild that practically all the snow which falls in the winter is melted 

 away during the succeeding summer, but ages ago the climate of 

 all the United States was much more severe than it is to-day, and 

 large glaciers were formed on almost every mountain peak. The 

 most favorable place for the snow to accumulate was on the north 

 and east sides, for it was not blown away by gales coming from the 

 west, and it was protected from the heat of the sun more than it 

 would have been on the other sides. Thus the glaciers were re- 

 stricted to the north and east sides, or at least they were more nuraer- 

 ous and larger there than they were on the other sides. 



In that far-off time fairly large glaciers lay on the side of Pikes 

 Peak, and they gouged out great amphitheaters or cirques, as they 

 are generally called, in the mountain side. In this manner the 

 original more gentle slope was converted to nearly vertical walls. 

 The rocky material that was removed from these cirques was carried 

 down by the glacier and deposited at its extremity as a ridge or mo- 

 raine or was washed down Fountain Creek. If the traveler wishes to 

 see how steep are the cliffs produced by a glacier he has only to walk 

 to the end of the Cogwheel Road and look down a thousand feet or 

 so into the rocky basin that the ice has cut. 



