es Jorasses, at Chamounix, mimicked in
its every jag by a line of clouds above it. Another resultant phenomenon
is the formation of cloud in the calm air to leeward of a steep summit;
cloud whose edges are in rapid motion, where they are affected by the
current of the wind above, and stream from the peak like the smoke of a
volcano, yet always vanish at a certain distance from it as steam
issuing from a chimney. When wet weather of some duration is
approaching, a small white spot of cloud will sometimes appear low on
the hill flanks; it will not move, but will increase gradually for some
little time, then diminish, still without moving; disappear altogether,
reappear ten minutes afterwards, exactly in the same spot; increase to a
greater extent than before, again disappear, again return, and at last
permanently; other similar spots of cloud forming simultaneously, with
various fluctuations, each in its own spot, and at the same level on the
hill-side, until all expand, join together, and form an unbroken veil of
threatening gray, which darkens gradually into storm. What in such cases
takes place palpably and remarkably, is more or less a law of formation
in all clouds whatsoever; they being bounded rather by lines expressive
of changes of temperature in the atmosphere, than by the impulses of the
currents of wind in which those changes take place. Even when in rapid
and visible motion across the sky, the variations which take place in
their outlines are not so much alterations of position and arrangement
of parts, as they are the alternate formation and disappearance of
parts. There is, therefore, usually a parallelism and consistency in
their great outlines, which give system to the smaller curves of which
they are composed; and if these great lines be taken, rejecting the
minutiae of variation, the resultant form will almost always be angular,
and full of character and decision. In the flock-like fields of equal
masses, each individual mass has the effect, not of an ellipse or
circle, but of a rhomboid; the sky is crossed and checkered, not
honeycombed; in the lower cumuli, even though the most rounded of all
clouds, the groups are not like balloons or bubbles, but like towers or
mountains. And the result of this arrangement in masses more or less
angular, varied with, and chiefly constructed of, curves of the utmost
freedom and beauty, is that appearance of exhaustless and fantastic
energy which gives every cloud a mar