PHYSICAL FEATURES OF COLORADO VALLEY. 387 



The agencies and conditions undei- which all of these features have 

 been formed deserve mention, and in this and following chapters I 

 shall briefly discuss this subject, in a manner as free from technical 

 terms as will be consistent with accurate description. 



The discussion will by no means be exhaustive, and I hope here- 

 after to treat this subject in a more thorough manner. In view of 

 these facts, I shall not attempt any logical classification of the ele- 

 ments of the topography, nor of the agencies and conditions under 

 which they were produced ; but, commencing at the north, at the ini- 

 tial point of the exploration, I shall take them up in geographic order, 

 as we proceed down the river. 



Bad Lands and Alcove Lands north of the Uinta Moun- 

 tains. The area north of the Uinta Mountains embraced in the sur- 

 vey is but small Through the middle of it runs Green River, in a 

 deep, narrow valley, the sides or walls of which sometimes approach 

 so near to each other, and are so precipitous, as to form a canon. 



The general surface of the country, on the north of this district, is 

 about 1,000 feet above the river, with peaks, here and there, rising a 

 few hundred feet higher ; but soutli, toward the Uinta Mountains, this 

 general surface, within a few miles of the river, gradually descends, 

 and at the foot of the mountains we find a valley on either side, with 

 a direction transverse to that of the course of Green River, and par- 

 allel to the mountain-range. 



To the north, the water-ways are all deeply eroded ; the perma- 

 nent streams have flood-plains of greater or lesser extent, but the 

 channels of the wet-weather streams, i. e., those which are dry during 

 the greater part of the year, are narrow, and much broken by abrupt 

 falls. 



The rocks arc the sediments of a dead lake, and are quite variable 

 in lithologic characteristics. We find thinly-laminated shales, hard 

 limestones, breaking with an angular fracture, crumbling Bad-Land 

 rocks, and homogeneous, heavily-bedded sandstones. 



The scenic features of the country are alike variable. On the clifts 

 about Green River City, towers and buttes are seen as you look from 

 below, always regarded by the passing traveler as strange freaks of 

 Nature. The limestones, interstratified with shales, give terraced and 

 buttressed characteristics to the escarpments of the canons and narrow 

 valleys. 



Immediately south of Bitter Creek, on the east side of Green River, 

 there is a small district of country which we have called the Alcove 

 Land. On the east it is drained by Little Bitter Creek, a dry gulch 

 much of the year. This runs north into Bitter Creek, a permanent 

 stream, which empties into the Green. The crest of this water-shed 

 is an irregular line, only two to four miles back from the river, but 

 usually more than 1,000 feet above it, so that the waters have a rapid 

 descent, and every shower-born rill has excavated a deep, narrow 



