292 



and its spring habit of russet, soft grays, and emerald, together with a 

 sky inimitable and as varied as the seasons, are as fertile in promise as 

 suffifient in contrasts. 



The canon has a general westerly direction, and is some eight miles 

 in length. About midway, a chain of lofty granitic escarpments borders 

 the north side of the stream, along which they extend nearly a mile in 

 truly Gothic grandeur. The lower mass occupies an angle in the caiion, 

 and viewed from below it may be imagined to bear striking resemblance 

 to a cathedral-pile. The upper cliffs form a sort of amphitheater extend- 

 ing several hundred yards along the stream, and whose pierced and 

 pinnacled heights rise 500 or 600 feet above the water in a sheer preci- 

 IDice, the face of which is vertically ribbed by the tendency of the rock 

 to assume a columnar structure ; however, in places it is solid, clustering 

 in monumental groups in the steep declivities, or towering like^ castellated 

 ruins in some promontory overlooking the gorge. 



Toward the upper end of the cliffs, a huge bowlder-like mass of dark- 

 green stone protrudes like an enormous excrescence from their base, and 

 which continues along the north side of the stream about one-fourth of 

 a mile. It then loses its distinctive character, and thence appears like 

 trap of various shades of dark brown and green, which may be traced 

 two or three miles up the caiion. This gigantic dike is traversed at 

 various angles by fractures, which have been filled with various mineral 

 substances, as black trap, quartz, &c. 



This portion of the caiion is frequently bordered by immense inclines, 

 descending from heights of a thousand feet or more, and composed of 

 the angular debris resultiog from the atmosiDheric degradation of igneous 

 ledges seated high up in the mountain-sides. These talus-slopes are 

 sometimes quite destitute of vegetation, though generally sparsely 

 grassed over and covered with pines, spruce, and cedar. The latter, 

 with a sparser representation of the piuon at this elevation (8,000 feet), 

 generally prevails in northern declivities, the pine and spruce occupying 

 the opposite and more exposed slopes. Even here the dwarf-oak is met 

 "with ; but the prevalence of the quaking-asp, which forms thickets be- 

 side the stream and high up in the adjacent mountains, plainly indicates 

 the altitude, as also does the occurrence of dense tracts of spruce. 



Just before reaching Macelroy Creek, by which an old trail gains the 

 Moreno Valley, a ledge of red feldspathic granite outcrops in the north 

 side of the canon, and a short distance above detached masses of gray 

 syenitic rock were observed. A few hundred yards above Macelroy 

 Creek, and perhaps a mile and a quarter from the upper entrance of the 

 cai5on, in a high ridge, round which the stream makes a sharp curve, a 

 reddish contorto-laminated gneiss occurs, and which also appears in the 

 little valley of Macelroy Creek. This rock continues thence nearly to 

 the Moreno Valley, apparently constituting an immense thickness, per- 

 haps interbedded with micaceous schists, and succeeded on the west by 

 a very h&rd red quartzose rock. These deposits appear to constitute the 

 high hills along the east border of the Moreno Valley (at least in the 

 neighborhood of the entrance of the Cimarron Caiion), and may possi- 

 bly also be found in Little Baldy. Similar rocks are said to occur in the 

 summit of Great Baldy, although none such were observed in the saddle 

 over which the Blackhorse trail passes. 



The Moreno Valley extends in a north-south direction nearly eighteen 

 miles, with an average width of two miles. It properly does not belong 

 to the system of shallow park-basins which were excavated out of the 

 Cretaceous and Tertiary formations, and to which Ute Valley belongs ; 

 but it rather pertains to the possibly older lake-basins, environed by the 



