362 REPORT UNITED STATES GEOLOGICAL SURVEY. 



Cottonwood groves. We found along tbis stream settlements of appar- 

 ently well located and successful farmers. 



Southeast from our point of crossing the Snake Eiver, rise the Elk- 

 head Mountains, a formidable range with numerous sharp peaks and a 

 deeply eroded drainage system. We followed an Indian trail for 10 miles 

 through a desolate rolling country, and then reached the government 

 wagon-road leading to the White Eiver agency. This road meanders 

 around the western flank of the Elkhead Mountains. While the forest- 

 clad mountains to our left rose witb majestic grandeur, affording a highly 

 pleasing aspect, the country to our rigbt, on the contrary, consisted of 

 a high-rol!ing, monotonous sage-prairie, with no distinct characteristics 

 as to orographic features. The road keeps close to Fortification Creek 

 after crossing a low divide which connects the undulating sage-plateau 

 with the Elkbead Mountains. This creek rises in the mountains to the 

 eastward, and contains for many miles tolerably good water, but in 

 approaching the terraced country bordering the Yampa Eiver on the* 

 north, the water assumes a very brackish character owing to its coming 

 in contact with many alkaline deposits. 



For many miles north of the Yam pa Eiver, the country slopes very grad- 

 ually towards the river ; its features are those of a monotonous wave- 

 like plateau country, with a covering of sage as its chief vegetation. The 

 only prominent topographical object in this region is an elevated and fl.at- 

 topped butte, named Fortification Butte, which stands like a rocky island 

 in the sage covered waving prairie. It stands some 12 miles north- 

 west of the point where the government road crosses the Yampa Eiver. 

 The Yampa Eiver is a fine clear stream of perhaps 100 feet in width, and 

 from 18 to 20 inches of depth in the centre of its bed. At the point of 

 our crossing it did not possess the charming features that characterized 

 the Snake Eiver Valley, although there are some good patches of bot- 

 tom in the numerous bends which the river makes in its meanderings 

 through the valley. 



Leaving the Yampa Eiver, the road follows through a somewhat more 

 mountainous region toward the White Eiver Ute agency. As this coun- 

 try belongs to the district allotted to us for observation, and in fact forms 

 the eastern portion of it, the notes in describing the area will have to 

 be somewhat fuller. While the air-line distance from the Yampa to 

 the valley of the White Eiver is but 38 miles, the road with its fre- 

 quent deviations from a straight course makes the distance 52 miles. 

 Within that distance the country exhibits different characters in its phy- 

 siognomy. The area is diversified or broken, first by three transverse 

 ridges, having an east and west trend, and running parallel to the Yampa 

 Eiver, and secondly by the caiion-valley of Williams Fork, as well as by a 

 basin-like depression between them. The first two of these ridges are 

 close together and separated only by the Williams Fork of the Yampa 

 which at the point where the road crosses it, as well as for many miles on 

 either side is in a deep caiion-like valley. The axis of the northern ridge, 

 or the one lying between the Yampa and Williams Fork, terminates near 

 the junction of the latter streams. The second ridge, the one lying 

 between Williams Fork and Axial Basin, extends its axis 12 miles 

 further to the west than does the former one. This latter portion of the 

 ridge, which is from 12 to 13 miles long, is penetrated by two streams 

 breaking rectangularly through the ridge, on their way to join Williams 

 Fork and Yampa Eiver. The eastern one of these streams is called 

 Waddel Creek, and joins Williams Fork 5 miles to the southeast of 

 the junction of the latter with the Yampa Eiver. The second creek 

 breaking through the ridge 7 miles below, or west of Waddel Creek, 



