GEOLOGICAL SURVEY OF THE TERRITORIES. 233 



a favorite grazing- ground of deer and e\k, whose tracks abounded, even 

 on the steepest slopes. I was here the victim of a curious delusion. 

 Looking up toward the fall, I saw what appeared to be patches of small 

 flowers, of a rich, blue color, closely resembling the patches of brilliant 

 blue " forget-me-nots," which ornament the higher crests above us. In 

 pursuit of them, [ pressed on until the spray became a drenching rain, 

 when suddenly I saw at my feet patches of the same blue ; but they 

 were only sky reflections from the wet rocks ! The walls of the cafion are 

 largely composed of soft volcanic ashes, hardly cemented, which disinte- 

 grate rapidly ; and the slopes are largely covered with sliding masses of 

 the sand thiis formed. Where this is reached by the spray of the fall, it is 

 partly further disintegrated into a bluish-gray mud, and subsequently 

 partially cemented into a fine-grained argillaceous sandstone, stratified 

 parallel to the slopes. These slopes descend directly into the river, so 

 that, even at the bottom, the utmost care must be used in walking. 

 Along the edge of the river, several small hot springs occur, which steam 

 moderately, but rarely to such an extent as to be visible from the top of 

 the canon. I was able to reach but one of these, which had a tempera- 

 ture of 150°. On the opposite bank, a miniature geyser was in opera- 

 tion ; from the top of a steep cone, about a foot high, a half-inch stream 

 was constantly spirting about a foot from the orifice. In ascending, I 

 followed the track of an elk, part of the way, and found much less diffi- 

 culty than in the descent. On the east slope, regular game-trails are 

 numerous ; and I think that most of the animals which graze on the 

 western spray-slope approach and leave it by fording or swimming the 

 river. 



Tbe upper faW, though less than one-third the height of the lower, 

 appears far grander, by reason of the momentum of the mass of water, 

 gained while rushing down the rapids which extend about a half mile 

 up stream. 



About 11 a. m. on the 23d, we started southward, passing the Crater 

 Hills and the Mud Geysers, and camped on the shore of the lake, near 

 its outlet, about 5 ]}. m., tbe distance being eighteen miles. The trails were 

 distinct and tolerably level. The soil here is very loose and washes 

 easily; so that, in many places, the trails made in 1870 and 1871 are 

 already badly gullied. This should be considered, in laying out roads 

 and trails through the x)ark. 



On most of the early maps of this region, a large lake is represented 

 at the head of the Yellowstone, under the name of Eustis's Lake, a name 

 supposed to have been given in honor of General Eustis, of the Engineer 

 Bureau. Later, it appears as Sublette's Lake; and now, for several 

 years, it has been called by the general name of Yellowstone Lake. If 

 any law of " priority" is to hold in geography, it would appear that the 

 name of Eustis should be again and permanently applied to it, unless 

 the original Indian name be ascertained and substituted for all later ones. 

 Aside from this general principle of priority, there is no doubt that the 

 present name is the best; and it has become so generally known that it 

 is likely to hold. The first map which, so far as known, re])resents the 

 lake with anything like its true form is a manuscript one by Jedediah 

 S. Smith, who hunted through the mountains from California to the 

 British Possessions, during the years from 1821 to 1830. Tbe original 

 was purchased in Oregon for the War Department, but is sui)posed to 

 have never reached Washington. A copy, taken in 1853, exists in the 

 hands of Mr. George Gibbs, of 'New Haven, Connecticut. 



When we arrived at the lake, in the afternoon, the usual daily wind 

 was blowing, and considerable waves were dashing upon the beach; but 



