zontal
flakes, the rolling form of the cumulus is both opposed in its principal
lines, and gifted with an apparent solidity and vastness, which no other
expedient could have exhibited, and which far exceed in awfulness the
impression of the noblest mountains of the earth. I have seen in the
evening light of Italy, the Alps themselves out-towered by ranges of
these mighty clouds, alternately white in the starlight, and inhabited
by fire.

Sec. 20. The deep-based knowledge of the Alps in Turner's Lake of Geneva.

Turn back to the first vignette in the Italy. The angular outlines and
variety of modulation in the clouds above the sail, and the delicate
atmosphere of morning into which they are dissolved about the breathing
hills, require no comment; but one part of this vignette demands
especial notice; it is the repetition of the outline of the snowy
mountain by the light cloud above it. The cause of this I have already
explained (vide page 228,) and its occurrence here is especially
valuable as bearing witness to the thorough and scientific knowledge
thrown by Turner into his slightest works. The thing cannot be seen once
in six months; it would not have been noticed, much less introduced by
an ordinary artist, and to the public it is a dead letter, or an
offence. Ninety-nine persons in a hundred would not have observed this
pale wreath of parallel cloud above the hill, and the hundredth in all
probability says it is unnatural. It requires the most intimate and
accurate knowledge of the Alps before such a piece of refined truth can
be understood.

Sec. 21. Further principles of cloud form exemplified in his Amalfi.

At the 216th page we have another and a new case, in which clouds in
perfect repose, unaffected by wind, or any influence but that of their
own elastic force, boil, rise, and melt in the heaven with more approach
to globular form than under any other circumstances is possible. I name
this vignette, not only because it is most remarkable for the buoyancy
and elasticity of inward energy, indicated through the most ponderous
forms, and affords us a beautiful instance of the junction of the
cirrostratus with the cumulus, of which we have just been speaking (Sec.
19,) but because it is a characteristic example of Turner's use of one
of the facts of nature not hitherto noticed, that the edge of a
partially transparent body is often darker than its central surface,
because at the edge the light penetrates and