The Crown of Wild Olive
rivers have serviceable deep places all along their banks, that ships
can sail in; but the wicked rivers go scoopingly irregularly under their
banks until they get full of strangling eddies, which no boat can row
over without being twisted against the rocks; and pools like wells,
which no one can get out of but the water-kelpie that lives at the
bottom;--but, wicked or good, the rivers all agree in having two kinds
of sides. Now the natural way in which a village stonemason therefore
throws a bridge over a strong stream is, of course, to build a great
door to let the cat through, and little doors to let the kittens
through; a great arch for the great current, to give it room in flood
time, and little arches for the little currents along the shallow shore.
This, even without any prudential respect for the floods of the great
current, he would do in simple economy of work and stone; for the
smaller your arches are, the less material you want on their flanks. Two
arches over the same span of river, supposing the butments are at the
same depth, are cheaper than one, and that by a great deal; so that,
where the current is shallow, the village mason makes his arches many
and low; as the water gets deeper, and it becomes troublesome to build
his piers up from the bottom, he throws his arches wider; at last he
comes to the deep stream, and, as he cannot build at the bottom of that,
he throws his largest arch over it with a leap, and with another little
one or so gains the opposite shore. Of course as arches are wider they
must be higher, or they will not stand; so the roadway must rise as the
arches widen. And thus we have the general type of bridge, with its
highest and widest arch towards one side, and a train of minor arches
running over the flat shore on the other; usually a steep bank at the
river-side next the large arch; always, of course, a flat shore on the
side of the small ones; and the bend of the river assuredly concave
towards this flat, cutting round, with a sweep into the steep bank; or,
if there is no steep bank, still assuredly cutting into the shore at the
steep end of the bridge.
Now this kind of bridge, sympathising, as it does, with the spirit of
the river, and marking the nature of the thing it has to deal with and
conquer, is the ideal of a bridge; and all endeavours to do the thing in
a grand engineer's manner, with a level roadway and equal arches, are
barbarous; not only because all monotonous forms are ugly in themselves,
but because the mind perceives at once that there has been cost
uselessly thrown away for the sake of formality.[248]
Well, to return to our continuity. We see that the Turnerian bridge in
Fig. 32. is of the absolutely perfect type, and is still farther
interesting by having its main arch crowned by a watch-tower. But as I
want you to note especially what perhaps was not the case in the real
bridge, but is entirely Turner's doing, you will find that though the
arches diminish gradually, not one is _regularly_ diminished--they are
all of different shapes and sizes: you cannot see this clearly in 32.,
but in the larger diagram, Fig. 34., opposite, you will with ease. This
is indeed also part of the ideal of a bridge, because the lateral
currents near the shore are of course irregular in size, and a simple
builder would naturally vary his arches accordingly; and also, if the
bottom was rocky, build his piers where the rocks came. But it is not as
a part of bridge ideal, but as a necessity of all noble composition,
that this irregularity is introduced by Turner. It at once raises the
object thus treated from the lower or vulgar unity of rigid law to the
greater unity of clouds, and waves, and trees, and human souls, each
different, each obedient, and each in harmonious service.
4. THE LAW OF CURVATURE.
There is, however, another point to be noticed in this bridge of
Turner's. Not only does it slope away unequally at its sides, but it
slopes in a gradual though very subtle curve. And if you substitute a
straight line for this curve (drawing one with a rule from the base of
the tower on each side to the ends of the bridge, in Fig. 34., and
effacing the curve), you will instantly see that the design has suffered
grievously. You may ascertain, by experiment, that all beautiful objects
whatsoever are thus terminated by delicately curved lines, except where
the straight line is indispensable to their use or stability: and that
when a complete system of straight lines, throughout the form, is
necessary to that stability, as in crystals, the beauty, if any exists,
is in colour and transparency, not in form. Cut out the shape of any
crystal you like, in white wax or wood, and put it beside a white lily,
and you will feel the force of the curvature in its purity, irrespective
of added colour, or other interfering elements of beauty.
Well, as curves are more beautiful than straight lines, it is necessary
to a good composition that its continuities of object, mass, or colour
should be, if possible, in curves, rather than straight lines or angular
ones. Perhaps one of the simplest and prettiest examples of a graceful
continuity of this kind is in the line traced at any moment by the corks
of a net as it is being drawn: nearly every person is more or less
attracted by the beauty of the dotted line. Now it is almost always
possible, not only to secure such a continuity in the arrangement or
boundaries of objects which, like these bridge arches or the corks of
the net, are actually connected with each other, but--and this is a
still more noble and interesting kind of continuity--among features
which appear at first entirely separate. Thus the towers of
Ehrenbreitstein, on the left, in Fig. 32., appear at first independent
of each other; but when I give their profile, on a larger scale, Fig.
35., the reader may easily perceive that there is a subtle cadence and
harmony among them. The reason of this is, that they are all bounded by
one grand curve, traced by the dotted line; out of the seven towers,
four precisely touch this curve, the others only falling back from it
here and there to keep the eye from discovering it too easily.
And it is not only always _possible_ to obtain continuities of this
kind: it is, in drawing large forest or mountain forms essential to
truth. The towers of Ehrenbreitstein might or might not in reality fall
into such a curve, but assuredly the basalt rock on which they stand
did; for all mountain forms not cloven into absolute precipice, nor
covered by straight slopes of shales, are more or less governed by these
great curves, it being one of the aims of Nature in all her work to
produce them. The reader must already know this, if he has been able to
sketch at all among the mountains; if not, let him merely draw for
himself, carefully, the outlines of any low hills accessible to him,
where they are tolerably steep, or of the woods which grow on them. The
steeper shore of the Thames at Maidenhead, or any of the downs at
Brighton or Dover, or, even nearer, about Croydon (as Addington Hills),
are easily accessible to a Londoner; and he will soon find not only how
constant, but how graceful the curvature is. Graceful curvature is
distinguished from ungraceful by two characters: first, its moderation,
that is to say, its close approach to straightness in some parts of its
course;[249] and, secondly, by its variation, that is to say, its never
remaining equal in degree at different parts of its course.
This variation is itself twofold in all good curves.
A. There is, first, a steady change through the whole line from less to
more curvature, or more to less, so that _no_ part of the line is a
segment of a circle, or can be drawn by compasses in any way whatever.
Thus, in Fig. 36., _a_ is a bad curve, because it is part of a circle,
and is therefore monotonous throughout; but _b_ is a good curve, because
it continually changes its direction as it proceeds.
The _first_ difference between good and bad drawing of tree boughs
consists in observance of this fact. Thus, when I put leaves on the line
_b_, as in Fig. 37., you can immediately feel the springiness of
character dependent on the changefulness of the curve. You may put
leaves on the other line for yourself, but you will find you cannot make
a right tree spray of it. For _all_ tree boughs, large or small, as well
as all noble natural lines whatsoever, agree in this character; and it
is a point of primal necessity that your eye should always seize and
your hand trace it. Here are two more portions of good curves, with
leaves put on them at the extremities instead of the flanks, Fig. 38.;
and two showing the arrangement of masses of foliage seen a little
farther off, Fig. 39., which you may in like manner amuse yourself by
turning into segments of circles--you will see with what result. I hope,
however, you have beside you by this time, many good studies of tree
boughs carefully made, in which you may study variations of curvature in
their most complicated and lovely forms.[250]
B. Not only does every good curve vary in general tendency, but it is
modulated, as it proceeds, by myriads of subordinate curves. Thus the
outlines of a tree trunk are never as at _a_, Fig. 40, but as at _b_. So
also in waves, clouds, and all other nobly formed masses. Thus another
essential difference between good and bad drawing, or good and bad
sculpture, depends on the quantity and refinement of minor curvatures
carried, by good work, into the great lines. Strictly speaking, however,
this is not variation in large curves, but composition of large curves
out of small ones; it is an increase in the quantity of the beautiful
element, _but not a change in its nature_.
5. THE LAW OF RADIATION.
We have hitherto been concerned only with the binding of our various
objects into beautiful lines or processions. The next point we have to
consider is, how we may unite these lines or processions themselves, so
as to make groups of _them_.
Now, there are two kinds of harmonies of lines. One in which, moving
more or less side by side, they variously, but evidently with consent,
retire from or approach each other, intersect or oppose each other:
currents of melody in music, for different voices, thus approach and
cross, fall and rise, in harmony; so the waves of the sea, as they
approach the shore, flow into one another or cross, but with a great
unity through all; and so various lines of composition often flow
harmoniously through and across each other in a picture. But the most
simple and perfect connexion of lines is by radiation; that is, by their
all springing from one point, or closing towards it: and this harmony is
often, in Nature almost always, united with the other; as the boughs of
trees, though they intersect and play amongst each other irregularly,
indicate by their general tendency their origin from one root. An
essential part of the beauty of all vegetable form is in this radiation:
it is seen most simply in a single flower or leaf, as in a convolvulus
bell, or chestnut leaf; but more beautifully in the complicated
arrangements of the large boughs and sprays. For a leaf is only a flat
piece of radiation; but the tree throws its branches on all sides, and
even in every profile view of it, which presents a radiation more or
less correspondent to that of its leaves, it is more beautiful, because
varied by the freedom of the separate branches. I believe it has been
ascertained that, in all trees, the angle at which, in their leaves, the
lateral ribs are set on their central rib is approximately the same at