452 GEOLOGICAL SURVEY OF THE TERRITORIES. 



which is situated south of the Eio Grande, and is marked on the map as 

 Eio Grande Pyramid. A little farther to the right, and still more dis- 

 tant, was a double-topped peak, afterward occupied as station 23, and 

 named Mount Oso. Still farther around, another distant, high peak 

 appeared to be the cultniuation of a high mountain mass; this is Mount 

 .ZEolus on the map. Nearly in the same direction, but much nearer, 

 there appeared a high plateau, extending over many degrees of the 

 horizon. Being more than twenty miles distant from us, and lying 

 wholly above timber-line, it was a very interesting feature in the land- 

 scape. At our distance it seemed to be covered with grass ; but this we 

 afterward found was not the case. Our subsequent experience showed us 

 that in this part of the country these high super-timber-line plateaus are 

 very common. Immediately beyond this area was a high mass of red- 

 colored mountains, afterward the scene of some interesting electrical 

 experiences. A few miles northwest of this group Uncompahgre Mount- 

 ain appeared, presenting on its north side the peculiar precipice which 

 distinguishes it from all the surrounding peaks. North of this a series 

 of ridges and plateaus extends from the high mountains to the Gunnison 

 River. 



Having made profile sketches of the mountains and drainage sketches 

 of the water-courses in the vicinity, and having taken angles to every 

 prominent peak, bluff, and stream junction visible, we started for camp. 

 The next morning found us on our way to the great San Juan country, 

 of which we had heard so much and found out so little. Our course at 

 first lay to the southwest, along the tJte trail, which leads from Los 

 Pinos over to the Rio Grande. We ascended one of the peaks in the 

 small group containing station 33 of the previous season, and had a 

 good view of the deep and rugged canons leading outward from the 

 center of the mass. In the several succeeding days we made stations 

 3, 4, and 5 on the high plateau already mentioned. From this plateau 

 we got the grandest view of Uncompahgre obtained from any station 

 during the summer. The full height of the great precipice stood out in 

 clear profile. Its striking resemblance to the profile of the Matterhom 

 gave us a wholesome dread of it, for as yet it had never been ascended 

 by any one, and we felt that to reach the summit might be beyond the 

 range of the possible. The plateau upon which we stood ranges in ele- 

 vation from 12,400 to 12,700 feet above the sea, and covers an area of 

 about fifteen square miles. We rode over it on our mules, to make the 

 statiou, and found it covered with loose rock, which in some places was 

 so rough as to necessitate long detours in going from one point to 

 another. As in many other cases which occurred subsequently, we 

 found this plateau covered with puddles of water, and wherever there 

 was soil it was always boggy. On the west and north sides it was ter- 

 minated by bluff's, ranging in height from 1,000 to 2,500 feet, the last 

 200 to 500 feet being nearly vertical. On the west side of the plateau 

 the bluff terminates below in rolling, timbered land, which extends a 

 little over a mile to the bed of Lake Fork. The total fall from the top 

 of the bluff to the stream is 4,000 feet, in a horizontal distance of one 

 and a half miles. 



Having finished this part of the country, we traveled down the White 

 Earth to the point at which it emerges from the upper caiion. Here 

 the new road from Saguache crosses it at a small angle, and, swinging- 

 far up to the north to avoid the high bluffs, it finally turns up Lake 

 Foik at a point about twelve miles from the crossing of the White 

 Earth. Thence our course lay up stream, and we traveled along just 

 west of our plateau stations and nearly under the bluffs. From a camp 



