GEOLOGICAL SUEVEY OF THE TERRITOEIES. 



125 



the geysers of this basin. I have therefore left undescribecl many as 

 interesting as those noticed in the preceding pages. 



On our return to the lake from this basin, we passed up the Fire-Hole 

 Eiver to its source in the divide. Early in the morning, as we were 

 leaving the valley, the grand old geyser which stands sentinel at the 

 head of the valley gave us a magnificent parting display, and with little 

 or no preliminary warning it shot up a column of water about 6 feet in 



Fig. 



THE B EE-HIV E. 



diameter to the height of 100 

 to 150 feet, and by a succes- 

 sion of imi3ulses seemed to 

 hold it up steadily for the 

 space of fifteen minutes, the 

 great mass of water falling 

 directly back into the basin, 

 and flowing over the edges 

 and down the sides in large 

 streams. When the action 

 ceases, the water recedes be- 

 yond sight, and nothing is 

 heard but the occasional es- 

 cape of steam until another 

 exhibition occurs. This is one 

 of the most accommodating 

 geysers in the basin, and during our stay played once an hour quite 

 regularly. On account of its apparent regularity, and its position 

 overlooking the valley, it was called by Messrs. Langford and Doane 

 "Old Faithful." It has built up a crater about 20 feet high around its 

 base, and all about it are decorations similar to those previously de- 

 scribed. 



On the morning of August 6, we 

 ascended the mountains at the head 

 of Fire-Hole Eiver, on our return to 

 the hot-spring camp on the Yellow- 

 stone Lake. We had merely caught 

 a glimpse of the wonderful physical 

 phenomena of this remarkable val- 

 ley. We had jnst barely gleaned a 

 few of the surface observations, 

 which only sharpened our desire for 

 a larger knowledge. There is no 

 doubt in my mind that these geysers 

 are more i>owerful at certain seasons 

 of the year than at others. We saw 

 them in midsummer, when the sur- 

 face waters are greatly diminished. 

 In the spring, at the time of the melt- 

 ing of the snows, the display of the 

 first-class geysers must be more fre- 

 powerful. Temperatures may vary somewhat, though those 



Fig. 6i 



STILL HOT SPRING AND PYRAMID 

 GEYSER BASIN. 



and 



the chart may be relied on as correct. 



beautiful scenery, its hot springs and geysers, with 



We left this valley, 



great 



quent 

 given on 

 with its 

 regret. 



Mr. Elliott has sketched an ideal section of a portion of the Upper 

 Geyser Valley, (Fig. C3,) which may convey a clearer conception of 

 the way in which we may suppose the waters of many of the springs 

 reach the surface. The lower portion of the section is basalt, then lake 



