162 F. V. Hayden—Hot Springs and Geysers 
It might be called one vast crater made up of thousands of 
smaller rents and fissures, out of which the fluid interior of the — 
earth fragments of rocks and volcanic dust have been erupted — 
in unlimited quantities. Hundreds of the nuclei or conesof 
these voleanic vents are now remaining, some of them rising to — 
a height of ten thousand to eleven thousand feet above the sea — 
The lake itself is about twenty-two miles long and avers 
ten or fifteen miles in width. Our soundings show it t0 eee 
an unusual average depth, though the greatest depth wine? wt 
, after a careful series of amie bid: ee 
The clear green shading, with the deep ultramarine hue te 
waters, adds not a little to the effect of the scene. The es 
has, at all seasons, nearly the temperature of cold spring watel- 
S i 27 feet. 
e were 
