THE ROCKY MOUNTAINS OF COLORADO. 

 By S. P. Emmons. 



Upon leaving Grand Junction the route passes from the basin of 

 the Colorado river into the Rocky mountain region, or, according to 

 Powell's and Gilbert's nomenclature, from the Plateau region into the 

 Park province. The name u Rocky Mountains" has been retained for 

 this most eastern and most elevated group of mountain ranges of the 

 Cordilleran system, because it was the one which was first seen by early 

 explorers after their weary journeys across the Great Plains, and is 

 therefore the one to which the name was first applied. It was called 

 the Park province from its great interior valleys, entirely closed in by 

 mountain ridges, which constituted the natural game preserves of the 

 various Indian tribes that formerly inhabited the surrounding lowlands. 



The route chosen for the party does not traverse any of the greater 

 of these parks or valleys, but follows the deeper and narrower drain- 

 age channels of more modern date, from whose fresher excavations and 

 cuts the geologists may more readily obtain by a passing glance an 

 insight into the internal structure of the region than he could from 

 the older, gentler, and more covered slopes of the parks. A description 

 of the region proceeds naturally from the east westward, rather than 

 in the direction by which it will be approached by the present party, 

 since on the eastern side its characteristic features are more strongly 

 and distinctly marked. While the general physiographical features 

 of the group as a whole arrange themselves along north and south 

 lines, the prevailing northwest and southeast trend of the Cordilleran 

 system is manifested in many details of the topography, as it is in 

 the internal geological structure. 



The eastern front of the group, facing the Great Plains, is formed 

 by the Colorado or Front range from the northern boundary of Colo- 

 rado south to Pueblo, a distance of about 200 miles. Further south it 

 is formed by the Wet Mountain and the Sangre de Cristo ranges, set 

 off successively a little to the west of each other en echelon, and sepa- 

 rated by northwest-trending indentations or bays. 



Pack or to the west of these come the Parks — the Xorth, Middle, and 

 South Parks, lying opposite the Colorado range; Wet Mountain valley, 

 on the thinks of the mountains of the same name, and San Luis park, 

 stretching along the western foot of the Sangre de Cristo range, whose 

 culminating point, Blanca Peak, is the highest mountain in Colorado. 



The western wall of the Xorth and Middle parks is formed by a siu- 



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