GEOLOGICAL SURVEY OF THE TERRITORIES. 



117 



the large orifice. The bottom of this great reservoir is covered with 

 thick spongiform masses, and in addition the rim is most elegantly 

 adorned with countless pearl-like beads, of all sizes. There are sev- 

 eral beautiful triangular reservoirs, IJ by 3 feet, set around the outer 

 sides of the rim, with numerous smaller ones, full of clear water, with 



Fig. 48. 









-' — -1: 



/ / 











^^^^^»^^tmf^^.^^,^^..^J^ 



GRAND GEYSER, UPPER BASIN G E Y S E R, F I R E-H O LE RIVER. 



hundreds of small depressions most beautifully scalloped. As vre 

 recede from the rim, the waters as they pass slowly away produce, by 

 evaporation, broad shallow basins, with thin, elegantly colored partitions, 

 portions of which have the form of toad-stools. When the water set- 

 tles into these depressions, or flows away toward the river in nume- 

 rous small channels, the wonderful variety of coloring which is so 

 attractive to the eye is produced. The large orifice seems to be in a 

 state of violent agitation as often as once in twenty minutes, raising up 

 the entire mass of water 10 or 15 feet. It is never altogether quiet. 

 Although these two orifices are within tlie same riiiif, I could not ascertain 

 that there is the slightest connection with each other. .When the hirge 

 orifice is much agitated it does not disturb the equanimity of the Grand 

 Geyser. They both operate perfectly independent of each other. Indeed, 

 I do not know that there is a connection between any of the springs in 

 the whole basin, though there may be in some rare cases. The Grand 

 Geyser operated twice while we were in the basin, with an interval of 



