ere sufficiently silicified to be packed
away among the collections.

[Illustration: THE UPPER YELLOWSTONE FALLS
FROM A PAINTING BY THOMAS MORAN]

In order that we might get a complete view of the Lower Geyser Basin
from some high point, we made a trip to the summit of Twin Buttes, on
the west side of the basin. From the top of one of these buttes, which
is six hundred and thirty feet above the Fire-Hole River, we obtained a
bird's-eye view of the entire lower portion of the valley, which was
estimated to be about twenty miles long and five miles wide. To the
westward, among the mountains, were a number of little lakes, which were
covered with a huge species of water-lily, _Nuphar advena_. The little
streams precipitated their waters in the most picturesque cascades or
falls. One of them was named by Colonel Barlow the "Fairy Fall," from
the graceful beauty with which the little stream dropped down a clear
descent of two hundred and fifty feet. It is only from a high point
that it can be seen, for the water falls gently down from the lofty
overhanging cliff into a basin at the foot, which is surrounded by a
line of tall pines one hundred to one hundred and fifty feet in height.
The continual flow of the waters of this little fountain has worn a deep
channel or furrow into the vertical sides of the mountain. As far as the
eye can reach can be seen the peculiar plateau mountain ranges, black
with the dense forests of pine, averaging from nine thousand to ten
thousand feet above sea-level....

A spring on a level with the river has an enormous square basin thirty
feet across, of unknown depth. We called this the "Bath Spring." A
little below is another singular form of wonderful beauty. The water
issues from beneath the crust near the margin of the river from several
apertures. The basin itself is fifteen by twenty feet and twenty feet
deep. It seemed to me that nothing could exceed the transparent
clearness of the water. The slightest object was reflected in its clear
depths, and the bright blue tints were indescribable. We called this the
"Cavern." The mud springs are also numerous and important in this group.
As usual, they are of all sizes, from an inch or two to twenty or thirty
feet in diameter, with contents varying from mere turbid water to stiff
mud. They seldom have any visible outlet, but are in a constant state of
agitation, with a sound that varies with the consistency of the
contents. There are severa