76 GEOLOGICAL SURREY OF THE TEERITOEIES. 



The effects of erosion, as shown in the Blue Eiver range, are on 

 equally as grand a scale as in other localities previously described. 

 Even the imagination fails to grasp the tremendous influence this agency 

 has exerted in past times, judging from the scenery both of mountain, 

 and plain. 



From the summit of Mount Powell one can follow with the eye the 

 sharp, zigzag crest of the Blue River range, with the numerous huge 

 amphitheaters on each side, which have been worn a long distance 

 from the base of the mountain. Very frequently the partition-wall is 

 broken through, forming a low bend or sag in the crest-line, and here 

 and there a huge shaft of granite rises up 1,000 feet or more above the 

 crest. 



The Blue range, as seen from the summit, is one of the ruggedest in 

 Colorado, composed of a mass of sharp-pointed peaks, crests, and obelisks. 

 Great masses of snow, like glaciers, lie on the almost vertical sides per- 

 petually, though they abruptly descend 45° or 50°. 



Huge fissures may be seen in these great masses of snow and ice, that 

 may indicate slow movements downward. At any rate, we may call 

 them remnants of the old glaciers that once existed here in abundance 

 and have left their traces on the surface everywhere. Numbers of little 

 gem-like lakes are seen high up in the amphitheaters, sometimes even 

 above timber-line, reservoirs for the water that melts from these old gla- 

 cier-remnants. 



A fact worthy of note here is the vast quantities of dead grasshoppers 

 that are found on these masses of snow. The quantity may be estimated 

 by bushels, and the bears frequent these high places in search of them 

 for food. At certain seasons of the year the air is filled with grasshop- 

 pers, apparently flying in every direction, to a height far beyond our . 

 vision. It is probable that they become chilled in flying over these 

 high mountain-peaks, and, dropping down on the snow, perish. 



The Blue River range juts up against the south rim of the Middle 

 Park, extending southward along the west side of the upper portion of 

 Blue River. On the east side of Blue River, there is a long, rather high 

 ridge, extending into the park, composed largely of Cretaceous shales 

 with dikes of basalt in great numbers. The basalt occurs on the sum- 

 mit and crops out of the sides in many places. 



Far in the distance to the northeast is the Front or Colorado range, 

 with Long's Peak, and the intermediate group of high peaks. To the 

 east, Torrey's and Gray's peaks are well shown, and to the southeast 

 are the peaks around the Middle Park. To the south is the Sawatch 

 range with the Holy Cross in the foreground, and west of south, Snow 

 Mass, Sopris, and other hig«h peaks can be distinctly seen. 



The intermediate space is filled up with the sedimentary beds, of which 

 the red beds cover by far the largest area. The Blue River range trends 

 about north and south, extending up so as to form the northern portion 

 of the Park range. Looking to the west we can seethe great mass of sedi- 

 mentary beds inclining from the west side of the Blue River range and 

 from the east side of the Holy Cross, and its associated peaks forming 

 about midway a curious synclinal. 



The two forces have crushed the beds together. The sedimentary 

 grouj) here forms a belt from fifteen to twenty miles in width, expanding 

 to a greater breadth to the west and northwest. To the northwest from 

 Mount Powell we can look into Egeria Park, a sort of elevated plateau 

 or meadow, a beautiful park, though small, about five miles in diameter 

 and nearly circular in shape. North of the middle park but not very 

 distinctly visible from Mount Powell, is the North Park. To the west, 



