e
apparent differences, dependent on proximity, are most marked and
important.

Sec. 2. Their marked difference in color.

In the first place, the clouds of the central region have, as has been
before observed, pure and aerial grays for their dark sides, owing to
their necessary distance from the observer; and as this distance permits
a multitude of local phenomena capable of influencing color, such as
accidental sunbeams, refractions, transparencies, or local mists and
showers, to be collected into a space comparatively small, the colors of
these clouds are always changeful and palpitating; and whatever degree
of gray or of gloom may be mixed with them is invariably pure and
aerial. But the nearness of the rain-cloud rendering it impossible for a
number of phenomena to be at once visible, makes its hue of gray
monotonous, and (by losing the blue of distance) warm and brown compared
to that of the upper clouds. This is especially remarkable on any part
of it which may happen to be illumined, which is of a brown, bricky,
ochreous tone, never bright, always coming in dark outline on the lights
of the central clouds. But it is seldom that this takes place, and when
it does, never over large spaces, little being usually seen of the
rain-cloud but its under and dark side. This, when the cloud above is
dense, becomes of an inky and cold gray, and sulphureous and lurid if
there be thunder in the air.

Sec. 3. And in definiteness of form.

Sec. 4. They are subject to precisely the same great laws.

With these striking differences in color, it presents no fewer nor less
important in form, chiefly from losing almost all definiteness of
character and outline. It is sometimes nothing more than a thin mist,
whose outline cannot be traced, rendering the landscape locally
indistinct or dark; if its outline be visible, it is ragged and torn;
rather a spray of cloud, taken off its edge and sifted by the wind, than
an edge of the cloud itself. In fact, it rather partakes of the nature,
and assumes the appearance, of real water in the state of spray, than of
elastic vapor. This appearance is enhanced by the usual presence of
formed rain, carried along with it in a columnar form, ordinarily, of
course, reaching the ground like a veil, but very often suspended with
the cloud, and hanging from it like a jagged fringe, or over it in
light, rain being always lighter than the cloud it falls from. These
columns, or fringes, of rain are