ejdiich.] SWEETWATER DISTRICT TOPOGRAPHY. 45 



GRANITE HILLS. 



• 



A decided break occurs in the even slope of the plateau by the unex- 

 pected protrusion of a series of more or less isolated granitic ridges or 

 hills. About 18 miles above the Three Crossings, on the Sweetwater, the 

 first of these hills are noticed. Heavy masses of isolated red granite rise 

 considerably above the surrounding tertiary deposits. As we travel from 

 that point eastward, the hills make their appearance at shorter intervals, 

 and are eventually counected so as to form more or less extensive ridges. 

 A short distance below the Three Crossings they assume the type of a 

 compact groupe. Connected with each other, to the exclusion of the 

 tertiary sediment, the hills here present a very striking appearance. 

 They are almost entirely destitute of vegetation, and show peculiarly 

 rounded, smooth surfaces. Nearly the whole mass of these hills remains 

 north of the Sweetwater, and only small, isolated fragments of the granite 

 make their appearance south of the river until we reach the Devil's Gate. 

 Hayden's Peak is the most prominent one of the group. Cloven Peak is 

 another sharply-defined hill in the group. On several maps the inscription 

 '" Granite Hills " or ' i Granite Eidges " may be found. It is to be presum ed 

 that these names were put on rather to convey some definite information 

 than to represent the appellation given to the group. The first name, 

 however, is a descriptive one, and I have adopted it for these granitic 

 exposures. As we proceed still farther to the east, we find the " Devil's 

 Gate " within the area occupied by the hills. Near the one hundred and 

 seventh meridian, Eock Independence,; a most famous landmark, is 

 located. This is merely a huge block of granite, isolated from the main 

 portion of the hills by intervening area's of sand. Northward of the 

 Granite Hills the edge of the Sweetwater Plateau continues eastward, 

 and this, as well as the hills, extends beyond the limits of our district. 



At the point where granitic buttes first make their appearance they 

 are about 8 miles north of the river. Trending in a southeasterly direc- 

 tion, they reach it about 12 miles above the Three Crossings. Although 

 the Sweetwater usually winds its way around them, it cuts through nar- 

 row ridges at a number of places. Most prominent among these is its 

 passage through the Devil's Gate. While the group of hills has, up to 

 that point, maintained a course nearly due east and west, it here takes a 

 sudden bend to the southeastward, the river cuts through it, and flows 

 onward north of the hills. So far as we could determine from a distance, 

 the Granite Hills eventually connect with the eastern extension of the 

 Seminole Mountains. Seen from long distances, this group presents a 

 very rugged appearance. No timber exists on the hills to modify their 

 outlines, and the impression obtained is that of a high range. Eising 

 abruptly from a very gentle, regular slope, they closely resemble rocky 

 islands projecting above the level of the sea. Even in their present form 

 do they thus afford a reminiscence of the conditions existing at that 

 locality ages ago. 



WIND RIVER RANGE. 



Within our district is included a portion of the Wind Eiver Eange. 

 All that part lying south of north latitude 43° fell to our share. That 

 section of the Eocky Mountain system which has received the name of 

 the Wind Eivers forms the continental divide for a considerable distance 

 within our district. So far as explored by us, the range is a very typical 

 one, regular in its structure and in the distribution of its several mem- 

 bers. It may appropriately be divided into three chains — the main or 

 western, the chain of foot-hills, and the chain of outlying hills. Of these 



