n several
inches, and the temperature slowly falls to 150 deg.. We called this the
"Grand Geyser," for its power seemed greater than any other of which we
obtained any knowledge in the valley.

[After describing more particularly the peculiarities of the
Grand Geyser and the smaller neighboring geysers, Dr. Hayden
gives us an enthusiastic pen-picture of a beautiful type of
springs.]

On the summit of the great mound is one of a class I have called central
springs; it is located on the highest point of the mound on which this
great group belongs; has a crater twenty feet in diameter, very nearly
quiescent, slightly bubbling, or boils near the centre, with a thin,
elegant rim projecting over the spring, with the water rising within a
few inches of the top. The continual but very moderate overflow of this
spring, uniformly on every side, builds up slowly a broad-based mound,
layer by layer, one-eighth to one-sixteenth of an inch thick. Looking
down into these springs, you seem to be gazing into fathomless depths,
while the bright blue of the water is unequalled even by the sea. There
are a number of these marvellous central springs, with projecting rims
carved with an intricate delicacy which of itself is a marvel; and as
one ascends the mound and looks down into the wonderfully clear depths,
the vision is unique. The great beauty of the prismatic colors depends
much on the sunlight, but about the middle of the day, when the bright
rays descend nearly vertically, and a slight breeze just makes a ripple
on the surface, the colors exceed comparison; when the surface is calm
there is one vast chaos of colors, dancing, as it were, like the colors
of a kaleidoscope.

As seen through this marvellous play of colors, the decorations on the
sides of the basin are lighted up with a wild, weird beauty which wafts
one at once into the land of enchantment; all the brilliant feats of
fairies and genii in the "Arabian Nights" entertainments are forgotten
in the actual presence of such marvellous beauty; life becomes a
privilege and a blessing after one has seen and thoroughly felt these
incomparable types of nature's cunning skill....

Our search for new wonders leading us across the Fire-Hole River, we
ascended a gently incrusted slope, and came suddenly upon a large oval
aperture with scalloped edges, the diameters of which were eighteen and
twenty-five feet, the sides corrugated and covered with a grayish-white