The
snow is first built out from the banks in bossy, over-curling drifts,
compacting and cementing until the streams are spanned. They then flow
in the dark beneath a continuous covering across the snowy zone, which
is about thirty miles wide. All the Sierra rivers and their tributaries
in these high regions are thus lost every winter, as if another glacial
period had come on. Not a drop of running water is to be seen excepting
at a few points where large falls occur, though the rush and rumble of
the heavier currents may still be heard. Toward spring, when the weather
is warm during the day and frosty at night, repeated thawing and
freezing and new layers of snow render the bridging-masses dense and
firm, so that one may safely walk across the streams, or even lead a
horse across them without danger of falling through. In June the
thinnest parts of the winter ceiling, and those most exposed to
sunshine, begin to give way, forming dark, rugged-edged, pit-like sinks,
at the bottom of which the rushing water may be seen. At the end of June
only here and there may the mountaineer find a secure snow-bridge. The
most lasting of the winter bridges, thawing from below as well as from
above, because of warm currents of air passing through the tunnels, are
strikingly arched and sculptured; and by the occasional freezing of the
oozing, dripping water of the ceiling they become brightly and
picturesquely icy.
Pages:
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56