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Show RECONNAISSANCE IN THE UTE COUNTRY. 77 ing up the valley of Ohio Creek and approaching Mount Umbraculum, in one mile I passed from arid sterility to fertility and exuberance in vegetation that equaled the far- famed prairies of Illinois. This close relation between timber and the rains is a rule without an exception so far as my observations have extended. Soon after leaving Camp 14, at an elevation of 9,280 feet, observed a thick formation of a sandstone conglomerate. This, with extensive beds of sandstone like that of yesterday, occurs during the march. At the head of Anthracite Creek, at an elevation of 9,100 feet, I observed the following section in descending order: No. 1, 75 feet hard, compact, light- brown sandstone, in thick, irregular beds. No. 2, 4£ feet anthracite coal; in luster and fracture resembles the Lehigh coal. No. 3, 90 feet black slate and black shale, interstratified with sandy shale. No. 4, creek bottom. This section dips down the stream, and soons disappears beneath the valley. The want of time precluded me from making an estimate of the extent of this formation, as this depends on contingencies somewhat intricate. The base of the mountain is composed of syenite, the higher portion of feldstone, trachyte, and volcanic tufa. * * On going down Nigger Creek, we found the mountains the same as on Anthracite Creek. I Ledges of brown sandstone were observed at several localities, and fragments of black slate in the creeks. Washington Gulch is an old place, situated on a small stream of the same name 300 feet below upper timber- line. A large amount of work was done here in washing for gold, but for the want of remunerative returns the mines have been abandoned. The bed- rock is of a hard blue slate, that disintegrates into small cu-boidal fragments. I traced this slate, alternating with dark- brown indurated clay, for six miles down the gulch to its mouth, at the foot of Lone Mountain, opposite Nigger Gulch, where I found two casts of fos- . sils, resembling Inoceramus, but too imperfect for identification. These formations are in horizontal strata, and their aggregate thickness amounts to several thousand feet. Lone Mountain is composed of gray granite; but the high peaks at the head of Washington Gulch are of volcanic origin. At several points on the march down Slate Eiver, a tributary of Taylor Eiver, I observed the blue slate formation of the preceding march, especially opposite East Eiver. The lower slopes of the mountains are mostly covered with surface-deposits. * In the mouth of the valley of East Eiver is a ledge of calcareous tufa. Higher up on the slope, the formations are of a quartzose character. One mile above the mouth of the valley and sixty feet above the base, is a high ledge of irregular stratified limestone, seventy- five feet in height, somewhat changed by heat. Found no organic remains except a small incurved shell not identified. This ledge is but a fragment, and lies over red feldspathic granite, which has incorporated with it irregular masses of gneiss. A short distance above this, granite forms the side walls of a deep and narrow canon above five furlongs in length. Above the canon, limestone and |