er of the rock is most
distinctly seen; the effect being increased in many limestones by the
interposition of two or three thinner beds between the large strata of
which the block has been a part; these thin laminae breaking easily, and
supplying a number of fissures and lines at the edge of the detached
mass. Thus, as a general principle, if a rock have character anywhere,
it will be on the angle, and however even and smooth its great planes
may be, it will usually break into variety where it turns a corner. In
one of the most exquisite pieces of rock truth ever put on canvas, the
foreground of the Napoleon in the Academy, 1842, this principle was
beautifully exemplified in the complicated fractures of the upper angle
just where it turned from the light, while the planes of the rock were
varied only by the modulation they owed to the waves. It follows from
this structure that the edges of all rock being partially truncated,
first by large fractures, and then by the rounding of the fine edges of
these by the weather, perpetually present _convex_ transitions from the
light to the dark side, the planes of the rock almost always swelling a
little _from_ the angle.

Sec. 3. Salvator's acute angles caused by the meeting of concave curves.

Now it will be found throughout the works of Salvator, that his most
usual practice was to give a _concave_ sweep of the brush for his first
expression of the dark side, leaving the paint darkest towards the
light; by which daring and original method of procedure he has succeeded
in covering his foregrounds with forms which approximate to those of
drapery, of ribbons, of crushed cocked hats, of locks of hair, of waves,
leaves, or anything, in short, flexible or tough, but which of course
are not only unlike, but directly contrary to the forms which nature has
impressed on rocks.[58]

Sec. 4. Peculiar distinctness of light and shade in the rocks of nature.

Sec. 5. Peculiar confusion of both in the rocks of Salvator.

And the circular and sweeping strokes or stains which are dashed at
random over their surfaces, only fail of destroying all resemblance
whatever to rock structure from their frequent want of any meaning at
all, and from the impossibility of our supposing any of them to be
representative of shade. Now, if there be any part of landscape in which
nature develops her principles of light and shade more clearly than
another, it is rock; for the dark sides of fractured stone