determine, with
the single precaution that their edges should be tolerably irregular,
supplied, in hundreds of instances, a sky quite good enough for all
ordinary purposes--quite good enough for cattle to graze, or boors to
play at nine-pins under--and equally devoid of all that could gratify,
inform, or offend.

Sec. 3. The clouds of Salvator and Poussin.

But although this kind of cloud is, as I have said, typical of the
central region, it is not one which nature is fond of. She scarcely ever
lets an hour pass without some manifestation of finer forms, sometimes
approaching the upper cirri, sometimes the lower cumulus. And then in
the lower outlines, we have the nearest approximation which nature ever
presents to the clouds of Claude, Salvator, and Poussin, to the
characters of which I must request especial attention, as it is here
only that we shall have a fair opportunity of comparing their skies with
those of the modern school. I shall, as before, glance rapidly at the
great laws of specific form, and so put it in the power of the reader to
judge for himself of the truth of representation.

Sec. 4. Their essential characters.

Sec. 5. Their angular forms and general decision of outline.

Clouds, it is to be remembered, are not so much local vapor, as vapor
rendered locally visible by a fall of temperature. Thus a cloud, whose
parts are in constant motion, will hover on a snowy mountain, pursuing
constantly the same track upon its flanks, and yet remaining of the same
size, the same form, and in the same place, for half a day together. No
matter how violent or how capricious the wind may be, the instant it
approaches the spot where the chilly influence of the snow extends, the
moisture it carries becomes visible, and then and there the cloud forms
on the instant, apparently maintaining its form against the wind, though
the careful and keen eye can see all its parts in the most rapid motion
across the mountain. The outlines of such a cloud are of course not
determined by the irregular impulses of the wind, but by the fixed lines
of radiant heat which regulate the temperature of the atmosphere of the
mountain. It is terminated, therefore, not by changing curves, but by
steady right lines of more or less decision, often exactly correspondent
with the outline of the mountain on which it is formed, and falling
therefore into grotesque peaks and precipices. I have seen the marked
and angular outline of the Grand