d
as November mists; then sending it forth again to breathe lightly
across the slopes of velvet fields, or to be scorched among sunburnt
shales and grassless crags; then drawing it back in moaning swirls
through clefts of ice, and up into dewy wreaths above the snow-fields;
then piercing it with strange electric darts and flashes of mountain
fire, and tossing it high in fantastic storm-cloud, as the dried grass
is tossed by the mower, only suffering it to depart at last, when
chastened and pure, to refresh the faded air of the far-off plains.

The third great use of mountains is to cause perpetual change in the
_soils_ of the earth. Without such provision the ground under
cultivation would in a series of years become exhausted, and require
to be upturned laboriously by the hand of man. But the elevations of
the earth's surface provide for it a perpetual renovation. The higher
mountains suffer their summits to be broken into fragments, and to be
cast down in sheets of massy rock, full, as we shall see presently, of
every substance necessary for the nourishment of plants; these fallen
fragments are again broken by frost, and ground by torrents, into
various conditions of sand and clay--materials which are distributed
perpetually by the streams farther and farther from the mountain's
base. Every shower that swells the rivulet enables their waters to
carry certain portions of earth into new positions, and exposes new
banks of ground to be mined in their turn. That turbid foaming of the
angry water,--that tearing down of bank and rock along the flanks of
its fury,--are no disturbances of the kind course of nature; they are
beneficent operations of laws necessary to the existence of man, and
to the beauty of the earth. The process is continued more gently, but
not less effectively, over all the surface of the lower undulating
country; and each filtering thread of summer rain which trickles
through the short turf of the uplands is bearing its own appointed
burden of earth to be thrown down on some new natural garden in the
dingles beneath.

I have not spoken of the local and peculiar utilities of mountains. I
do not count the benefit of the supply of summer streams from the
moors of the higher ranges,--of the various medicinal plants which are
nested among their rocks,--of the delicate pasturage which they
furnish for cattle,--of the forests in which they bear timber for
shipping,--the stones they supply for building, or the