e. The
drawing of the solid form is worse still, for it is to be remembered
that although clouds of course arrange themselves more or less into
broad masses, with a light side and dark side, both their light and
shade are invariably composed of a series of divided masses, each of
which has in its outline as much variety and character as the great
outline of the cloud; presenting, therefore, a thousand times repeated,
all that I have described as characteristic of the general form. Nor are
these multitudinous divisions a truth of slight importance in the
character of sky, for they are dependent on, and illustrative of, a
quality which is usually in a great degree overlooked,--the enormous
retiring spaces of solid clouds. Between the illumined edge of a heaped
cloud, and that part of its body which turns into shadow, there will
generally be a clear distance of several miles, more or less of course,
according to the general size of the cloud, but in such large masses as
in Poussin and others of the old masters, occupy the fourth or fifth of
the visible sky; the clear illumined breadth of vapor, from the edge to
the shadow, involves at least a distance of five or six miles. We are
little apt, in watching the changes of a mountainous range of cloud, to
reflect that the masses of vapor which compose it, are huger and higher
than any mountain range of the earth; and the distances between mass and
mass are not yards of air traversed in an instant by the flying form,
but valleys of changing atmosphere leagues over; that the slow motion of
ascending curves, which we can scarcely trace, is a boiling energy of
exulting vapor rushing into the heaven a thousand feet in a minute; and
that the toppling angle whose sharp edge almost escapes notice in the
multitudinous forms around it, is a nodding precipice of storms, 3000
feet from base to summit. It is not until we have actually compared the
forms of the sky with the hill ranges of the earth, and seen the soaring
Alp overtopped and buried in one surge of the sky, that we begin to
conceive or appreciate the colossal scale of the phenomena of the
latter. But of this there can be no doubt in the mind of any one
accustomed to trace the forms of clouds among hill ranges--as it is
there a demonstrable and evident fact, that the space of vapor visibly
extended over an ordinarily cloudy sky, is not less, from the point
nearest to the observer to the horizon, than twenty leagues; that the
size