ion of an infinite curve, almost
too delicate to be traced; except the short lowest one, which is made
quite straight, to oppose the rest.

[Illustration: FIG. 98.]

I give one more example from another leaf of the same manuscript, Fig.
99, merely to show the variety introduced by the old designers between
page and page. And, in general, the reader may take it for a settled law
that, whatever can be done by machinery, or imitated by formula, is not
worth doing or imitating at all.

Sec. 20. The quantity of admissible transgression of law varies with the
degree in which the ornamentation involves or admits imitation of
nature. Thus, if these ivy leaves in Fig. 99 were completely drawn in
light and shade, they would not be properly connected with the more or
less regular sequences of the scroll; and in every subordinate ornament,
something like complete symmetry may be admitted, as in bead mouldings,
chequerings, &c. Also, the ways in which the transgression may be
granted vary infinitely; in the finest compositions it is perpetual, and
yet so balanced and atoned for as always to bring about more beauty than
if there had been no transgression. In a truly fine mountain or organic
line, if it is looked at in detail, no one would believe in its being a
continuous curve, or being subjected to any fixed law. It seems broken,
and bending a thousand ways; perfectly free and wild, and yielding to
every impulse. But, after following with the eye three or four of its
impulses, we shall begin to trace some strange order among them; every
added movement will make the ruling intent clearer; and when the whole
life of the line is revealed at last, it will be found to have been,
throughout, as obedient to the true law of its course as the stars in
their orbits.

[Illustration: FIG. 99.]

The four systems of mountain line.

Sec. 21. Thus much may suffice for our immediate purpose respecting
beautiful lines in general. We have now to consider the particular
groups of them belonging to mountains.

The lines which are produced by course of time upon hill contours are
mainly divisible into four systems.

1. Lines of Fall. Those which are wrought out on the solid mass by the
fall of water or of stones.

2. Lines of Projection. Those which are produced in debris by the
bounding of the masses, under the influence of their falling force.

3. Lines of Escape. Those which are produced by the spreading of debris
from a given point