40 GEOLOGICAL SURVEY OF THE TERRITORIES. 



miles, aud arrive at tlie base of oue of the spurs extending from Mount 

 Lincoln, known in the country as Mount Bross. The entire mountain 

 is so thickly covered with surface-deposits that the angularities are 

 smoothed off, and the grass and flowers are quite abundant almost to 

 the summit. We find, however, on the summit, and around the sides of 

 the upper portion, remnants of the sedimentary beds, quartzites and 

 limestones, but the nucleus is a schistose granite. Silver-mines are 

 opened everywhere on the sides both of Mounts Bross and Lincoln. 

 On the latter peak there are mines of considerable value, which are 

 wrought by a company, full 14,000 feet above the sea and within a few 

 feet of the summit. The Montezuma mine is located within 100 feet of 

 the top. The silver-ores are confined mostly to the limestones and 

 quartzites, and are segregated, as it were, in the fissures in the most 

 irregular manner. There seem to be no regular lodes, but they are like 

 the silver-mines in the limestones and quartzites of Utah. Indeed, the 

 formations are so similar that a description of one locality would apply 

 substantially to the other. The mountain is composed mostly of schist- 

 ose gneiss, with the lines of bedding very distinct, and unconformably 

 upon it rest the secondary beds. The quartzites, mostly crystalline, 

 partially changed by heat, rest on the edges of the schists, then comes a 

 blue impure limestone full of pockets a.nd seams of quartz. Above 

 comes a thick bed of quartzites again, the whole mass a thousand to 

 fifteen hundred feet in thickness. The summit of the mountain is a 

 dike of porphyritic granite, which seems to have burst up in the form of 

 a wedge through all the sedimentary beds. The sides and summits of 

 the mountain are so covered with the broken masses of rock, mingled 

 with igneous, granitoid quartzites and limestones, that it is very diffi- 

 cult to obtain a clear section. On the east side of the mountain a sort 

 of gorge has been worn deep down between Bross and Lincoln, expos- 

 ing in the vertical sides the order of superposition quite clearly. 



The view from the summit of Mount Lincoln is wonderful in its ex- 

 tent. To the east, far distant, is distinctly seen Pike's Peak, with the 

 contiguous ranges which border the east side of the x)ark and extend 

 northward toward Long's Peak, all of which are granitoid. On the 

 west and northwest side of the i)ark is a vast group of high mountains, 

 gashed down on every side with deep gorges with vertical sides, reveal- 

 ing the strata of quartzites and limestones resting on the schists with 

 dikes of the trachyte. To the southward can also be seen the granite 

 nucleus, a remarkable range of mountains, the Sawatch, vvhich, with its 

 lofty peaks — among them Mounts Yale and Harvard — looms up like a 

 massive wall, with a wilderness of conical peaks along its summit. To the 

 east and southeast the park lies spread out to the view with its variety 

 of low ridges and meadow. These ridges are composed of all the sedi- 

 mentary beds uplifted known in this region. Some of them, covered 

 with basalts, with a trend nearly north and south, extend in regular 

 order far across the park, eastward. From the top of Mount Lincoln 

 more than fifty peaks rising to an elevation of 13,000 feet and upward, 

 and above two hundred over 12,000 feet, can be seen. Probably there 

 is no portion of the world, accessible to the traveling i^ublic, where 

 such a wilderness of lofty peaks can be seen within a single scope of 

 the vision. 



The liniestones and quartzites incline down the north slope of Mount 

 Lincoln to Hoosier Pass, which separates the waters of the Platte from 

 those of the Blue Eiver. The trend of the curious dike that caps Mount 

 Lincoln is about southwest and northeast. Silver-ore occurs to a great 



