of electric and magnetic storms.

Notwithstanding their variety, clouds are easily classified, and are
now by universal consent distinguished as follows.

In the higher regions of the air we look for the Cirri, the Curl
Clouds. They are light, lie in long ranges, apparently in the
direction of the magnetic pole, and are generally curled up at one
extremity. They are sometimes called Mackerel Clouds. They are
composed of thin white filaments, disposed like woolly hair, feather
crests, or slender net-work. They generally indicate a change of
weather, and a disturbance of the electric condition of the
atmosphere. When they descend into the lower regions of the air, they
arrange themselves in horizontal sheets and lose much of their
original type. The Germans call them Windsbaeume, or wind-trees.

The Cumulus is another form of cloud, which floats along in fleecy
masses, in the days of summer, but dissolves at night. Sometimes it
resembles a great stack or pile of snow, sometimes it has a silvery or
a golden edge, as if we saw a little of the lining. Sometimes they lie
motionless in the distance, and are mistaken by mariners for land.
They rest upon a large base, and are borne along by surface-winds.
Their greatest height is not more than two miles. They carry large
quantities of moisture with them, and, when preceding rain, fall
rapidly into other shapes.

The Stratus, or Fall Cloud, is horizontal in its figure, lies near the
earth, and its length is usually greater than its breadth. It floats
in long bands with rounded or sharpened points, and is seen rising
from rivers or lakes, at first as a fog. In the morning it indicates
fine weather. The Fall Cloud never discharges rain.

This comes only from the Nimbus, which is quite unlike the others. It
puts on a dark gray color, has irregular transparent edges, and
increases rapidly so as to obscure the sky. It appears to absorb the
other clouds, to be a union of their differently electrified
particles, which are attracted to each other, form drops of water, and
descend as rain.

Of the first three forms we have three modifications or varieties. The
Cirro-Cumulus is a congeries of roundish little clouds in close
horizontal position, varying in size and roundness, and often, to use
the words of the poet Bloomfield, appearing as "The beauteous
semblance of a flock at rest."

The Cirro-Stratus is more compact than the Cirrus,--the strata being
inclined or horizontal. It