ifferent Planes in Modelling and Carving--Egyptian System of
Relief Sculpture--Greek and Gothic Architectural Sculpture,
influenced by Structural and Ornamental Feeling--Sculptural
Tombs, Medals, Coins, Gems--Florentine Fifteenth-century
Reliefs--Desideriodi Settignano.

We come now to the consideration of the various means and methods of
expressing relief in line and form.

We may define a form in outline and give it different qualities of
expression by altering the quality and consistency of our outline, and
we may obtain very different kinds of decorative effect by the use of
lines of various degrees of thickness or thinness; but if we want to
give it force and colour, and to distinguish it from its background more
emphatically, we must add to our outline.

[Three Methods of Expressing Relief]

There are three principal methods or systems of giving relief by adding
to our outline.

One is the method of giving relief to form by contrasts of tone, colour,
or tint.

Another by means of the expression of light and shade: and the third by
means of modelling in relief.

Now, still keeping to expression by means of line, the three arms I have
sketched (p. 167[f092]) illustrate: (1) the form in outline alone; (2)
the contrast method; and (3) the light and shade method. The three pots
underneath illustrate the same three stages in a simpler manner.

In number one we see the outline defining the form pure and simple: in
number two the form is relieved by a half-tone formed of diagonal lines,
forming a plane or background behind it. The arm is still further
relieved by the dark drapery. Number three shows the relief carried
further by lines expressive of the modelling of the arm and the rounding
of the pot, and also by cast shadows from the forms.

[Illustration (f092): The Relief of Form: (1) By Outline, (2) By
Contrast, (3) By Light and Shade.]

The system of expressing relief I have termed relief by contrast
includes two kinds of contrast: there are the contrasts of line and
form, and there are the contrasts of planes of tone or tint and local
colour. We may consider that the contrast method covers generally all
forms of pattern and certain kinds of pictorial design. The method of
expressing relief by means of line covers generally all forms of design
in black and white, graphic sketching, pen-drawing, and work with the
point of all kinds.