118 GEOLOGICAL SURVEY OF THE TERRITORIES. 



its like again in any other part of the West. Long's Peak, with its double 

 spires, rises above the limits of vegetation into the regions of perpetual 

 snow, more than fourteen thousand feet above the level of the sea. AH 

 around are less lofty cones, many of them so covered with pines that 

 they look black and somber in the distance. Far to the southwest are 

 the snowy ranges that surround the North Park, and in the interme- 

 diate space are groups of lower peaks or cones, rising like steps to the 

 higher ranges. There is an interesting thought just here as to the real 

 origin of these granitic, ruin-like piles that give the peculiar distinction 

 to the plateau surface of the Laramie Mountains. I believe it is entirely 

 due to erosive forces, which have operated here on a gigantic scale, and 

 these cones and natural temples are the monuments that are left to tell 

 the tale. I am convinced that the surface was at one time at least on 

 a level with the highest of them. How much more has been removed 

 it is now impossible to tell, but I am convinced that comparatively few 

 geologists have fairly estimated the immensity of the time required and 

 the vastness of the amount of material removed from the surface by 

 erosion. 



Three miles west of Sherman we cross the head of Dale Creek, a 

 small stream which flows through a wide, gorge-like valley in the gran- 

 itic rocks. Spanning the valley is a bridge six hundred and fifty feet in 

 length, and one hundred and twenty-six feet above the little stream. 

 This bridge, which is well worthy of examination, forms one of the most 

 beautiful structures of the kind along this road, and always attracts the 

 attention of the traveler, who looks down from it upon a beautiful 

 grassy valley, through which winds a small stream, the whole walled in 

 with massive granite, like that before described. After crossing the 

 Dale Creek bridge we descend rapidly to the plains. On the west side 

 of the mountains we pass across the inclined edges of formations which 

 appear to be counterparts of those already alluded to on the east side. 

 We find the sandstones resting upon the granite, and inclining at a 

 greater or less angle westward; we also find the whitish and yellowish- 

 white limestones of the carboniferous period ; also the red sandstones, 

 which have usually been regarded as Triassic, though I suspect that the 

 upper portion, at least, is Jurassic; then come loose red sands, extend- 

 ing a considerable distance into the plains. If we continue on toward 

 the Big and Little Laramie Rivers, we shall fiud the cretaceous beds, in 

 full development, in a nearly horizontal position, and about thirty miles 

 still farther west the coal beds of the tertiary period are seen. 



But before We commence onr general remarks in regard to this 

 mountain range let us linger for a time among the singular and gro- 

 tesque forms which nature has hewn out of the sandstones on this 

 western slope. Here we may study some excellent illustrations of the 

 wearing away of sandstones through atmospheric agencies. We wish 

 as far as possible to present to the reader type examples of the influence 

 which the atmosphere, in its varied phases, has in shaping the features 

 of the landscape. 



We have illustrated some of the granitoid rocks of the mountain's 

 nucleus which have been metamorphosed by heat. Figure 9 is 

 exceedingly instructive in many points of view. The rock itself is a 

 moderately fine-grained sandstone, and varies in color from a yellowish 

 white to a light brick-red, and is probably of Jurassic age. No organic 

 remains have ever been found in the sandstones, although I have traced 

 them along the mountain sides from our north line to Santa Fe. The 

 reason why I call them Jurassic is, that a bed of limestone, which 

 inclines from the flank of the mountain higher up. seems to hold a lower 



