50 



GEOLOGICAL SURVEY OF THE TERRITORIES. 



observations were made by different members of the party, and some 

 additional facts were obtained l)y Dr. Peale. These will all appear in 

 subsequent portions of this report. We will, therefore, pass by the won- 

 derful basaltic columns, which are so finely shown in Fig. i). Tower Falls, 



Grand Canon, Upper 

 and Lower Falls of the 

 Yellowstone, as well as 

 the numerous groups 

 ')f hot springs, which 

 are abundant, can only 

 )e alluded to in gen- 

 ; ral terms. Some new 

 grou[)S of springs were 

 added to the list, but 

 lone that threw any 

 idditional light on 

 I heir history. There 

 are, no doubt, many 

 unall groups of springs 

 \et undiscovered. 



(irlowiug accounts 



were given to us 



of a 

 very interesting group 

 at the very source of 

 the West Branch of 

 Gardiner's River. 

 AVheu the National 

 Tark has been ren- 

 dered more easily ac- 

 cessible for travelers, 

 many curious discov- 

 eries will, no doubt, 

 be made which will in- 

 crease the public in- 

 terest in this wonder- 

 ful region. The origin 

 'of the r e m a rk able 

 lake-basin, in which 

 the greater part of the 

 wonders is located, is 

 most interesting in a 

 geological point of 

 view. I am convinced 



BASALTIC COLUMNS, YELLOWSTONE, NEAR MOUTH TOWER CKEEK.. that It IS UOt altOgCthCr 



one of eroston, but in part of elevation. It seems probable, however, that 

 the intense vohumic action, of which we see everywhere such unmistak- 

 able indications, occurred at a very modern geological period, not further 

 back than the Pliocene period, and perhaps even not later than what 

 we usually denominate the Quaternary or Drift. At any rate, it is 

 probable that the waters surrounded and perhaps covered the highest 

 mountain-peaks, inasmucli as we not only find drift-bowlders upon 

 most of the loftiest ranges, but the volcanic conglomerates, tuffs, &c., 

 are arranged in a stratitied and, for the most part, horizontal position 

 as high as the most elevated peaks in the Yellowstone Basin. On the 

 west side of the lake some of the highest peaks, as Pomeroy, Langford', 

 Stevenson, Doane, and others, are seemingly- huge-volcanic cones, com- 



