172 F. V. Hayden—Hoi Springs and Geysers 
These springs occur in small groups all over the basin, and 
are often in close proximity to geysers or to perfectly clear 
quiet springs. They are found in every stage, from simply tur- 
bid water, through all grades of consistency, to thick stiff mud, 
through which the gases force themselves with a suppressed — 
thud-like sound. Each of these mud springs probably com- — 
menced as a geyser or at least as a boiling spring. The water 
is at first clear, then becomes turbid, and grows gradually 
thicker until the heat dies out. 
face where the water flows. This coating in the old springs 
becomes broken up, so that it is suspended all over the sides of 
the springs like rotten mouldy fragments of leather. The ion 
is undoubtedly held together by vegetable matter. When these 
springs entirely dry up, these leathery fragments are blown 
about the surface in every direction by the winds ae 
In the vicinity of the active geysers, the surface over which — 
the surplus water from an eruption flows is sometimes covered, 
to the thickness of two to four inches, with a substance which 
appears to the touch like jelly or pulp. All over the surface 
there are irregular depressions with sharp raised edges, like the 
inner surface of a cow’s stomach. The colors are varied, bemg — 
usually a white base with every variety of scarlet, pink or Ts 
color, with brilliant shades of green. 
Another interesting feature was the quantity of inerusted 
and silicified wood found scattered about the springs. Very free 
quently the pine trees, which are abundant in the vicinity, have — 
G Up the Firehole river about ten miles, there is the Upper 
eyser Basin, where the great geysers are foun 
