OVEKL 



COUITCIL BLUFFS TO OGDEN. 



48 



This easy approach to the mountmns was discovered in a pecuhar 

 manner. For more than two yeare engineers had searched in vain 

 for a practicable grade by which the raihoad might reach the summit 

 of the range. On one of their excursions in the valley of Crow Creek 



r 



they discovered Indians between them and their escort of mounted 

 soldiers. In their attempt to find a point where the cavalry could 

 see their signals for help the engineers reached the ridge, and in order 

 to get to a place of safety they traveled down the ridge and found that 

 it joined the plain east of the mountains without a break. This was 

 just such a grade as they had been looking for, and further exploration 

 showed that it was suitable for the road. 



The station at Granite Canyon is built on granite porphyry, a 



This particular granite porphyry 



cr> 



stallnie rocK oi ig 



Granite Canyon. 



Elevation 7,312 feet. 

 Omaha 5;i5 miles. 



is the oldest rock yet encountered on this route, being 



West of the station is a steep 



Cambri 



gramte 



formation alonor 



O 



slope cut in the Brule clay, which lies directly on the 



porplu'ry. This is the westernmost exposure 



the Union Pacific line. • About 4 miles west of 

 the Granite Canyon station, near Ozone, the road crosses a narrow 

 strip of dark-colored granite gneiss, intruded ages ago into the older 

 crystalline rock which constitutes the core of the Laramie Rano-e, 



Yicin 



• — — ^ *^^ ^ -- - 



obtained of the high peaks of the Rocky Mountains far awa}^ to 



the left (south) and of the relatively low but rugged 

 Shennan Mountains, a part of the Laramie Range, to 



Two prominent points seen to the north 

 are called Twin Mountains and are celebrated as one 



Buford. 



Elevation 7,858 fe 

 Omaha 543 miles. 



the right. 



of the strongholds of the notorious desperado Slade. 



all 



more 



800 miles. The quarry is in the crystalline rock of the Laramie 

 Range, known as the Shennan granite.^ At Buford tliis granite has 



forms 



mass 



Cambrian time. It is normally a coarse- 



grained rock cc 

 feldspar, glassy 



hiefly of pink 

 quartz, black 

 ch in mass trive 



it a spotted appearance. According to 

 report it contains some gold at Buford but 

 not enough for profitable extraction. It 

 shows considerable variation in texture, 

 color, and compo^sition. One of the com- 

 monest varieties is coarsely porphyritic, 

 the feldspar standing out in crystals 1 to 

 2 inches in length. Where the Union 



i 



Pacific! Railroad crosses Dale Creek, west 

 of Sherman, the granite is rich in epidote, 

 a green mineral, which together with the 

 red feldspar imparts to it a mottled red 

 and green color. Although hard when 

 unaltered the Sherman gramte breaks up 

 readily into a coarse gravelly soil under 

 the influence of heat, cold, and the action 

 of water, so that it forms smooth, round 

 hills. Where the rock is firm it weathers 

 along widely spaced joints and forms heaps 

 of rounded bowlders, many of which may 

 be seen from the tram (Pi. VIII, ,1}, par- 

 ticularly west of Euford. 



