orces that produced so marvelous a change?

Snowflakes,--"flowers of the air",--as John Muir so poetically calls
them. They accomplished the work. Falling alone they could have done
nothing, but coming down in vast numbers, day after day, they piled
up and became a power. Snow forms glaciers, and glaciers are mighty
forces that create things.

[Illustration: Gilmore Lake, Pyramid Peak and the Crystal Range,
in winter, from summit of Mount Tallac]

[Illustration: Desolation Valley, Looking Toward Mosquito Pass]

[Illustration: Heather Lake, near Glen Alpine]

[Illustration: Susie Lake, near Glen Alpine Springs]

Let us, if possible, stand and watch the Master Workman
doing the work that is to make this region our source of present
day joy. We will make the ascent and stand on the summit
of Pyramid Peak. This is now 10,020 feet above sea level,
rising almost sheer above Desolation Valley immediately at our feet.

The first thing that arrests the visitor's attention is the peculiar
shape of the peak upon which he stands, and of the whole of the
Crystal Range. Both east and west it is a great precipice, with a
razor-like edge, which seems to have been especially designed for
the purpose of arresting the clouds and snow blown over the mountain,
ranges of the High Sierras, and preventing their contents falling upon
the waste and thirsty, almost desert-areas of western Nevada, which
lie a few miles further east.

Whence do the rains and snow-storms come?

One hundred and fifty miles, a trifle more or less, to the westward
is the vast bosom of the Pacific Ocean. Its warm current is constantly
kissed by the fervid sun and its water allured, in the shape of mist
and fog, to ascend into the heavens above. Here it is gently wafted by
the steady ocean breezes over the land to the east. In the summer the
wind currents now and again swing the clouds thus formed northward,
and Oregon and Washington receive rain from the operation of the sun
upon the Pacific Ocean of the south. In June and July, however, the
Tahoe region sees occasional rains which clear the atmosphere, freshen
the flowers and trees, and give an added charm to everything. But in
the fall and winter the winds send the clouds more directly eastward,
and in crossing the Sierran summits the mist and fog become colder and
colder, until, when the clouds are arrested by the stern barriers
of the Crystal Range, and necessity compels them to discharge their
burden, th