out a pattern; for carrying out fig. 14 it would be
well to pencil out the surface as in fig. 15; a connection between these
two will be perceived at a glance. This spacing-out of the required
surface in one way or another is of great assistance, and may even prove
suggestive in the planning of the design. It helps the regularity of the
work, and order is essential in design as in most other things in life.

[Illustration: Fig. 14.]

Another very usual expedient is that of introducing a main central form,
with others branching out on either side and symmetrically balancing
each other. An example of this is given in fig. 16. The symmetry may be
much more free than this; a tree is symmetrical taken as a whole, but
the two sides do not exactly repeat each other.

[Illustration: Fig. 15.]

A plan very commonly employed is that of radiating main lines all
diverging from one central point. Fig. 17 shows a design following this
principle; there is infinite variety in the ways in which this may be
carried out.

[Illustration: Fig. 16.]

[Illustration: Fig. 17.]

Another method would be to plan a continuous flowing line with forms
branching out on one side or on both. Figs. 18 and 19 are border
designs, for which purpose this arrangement is often used, though it can
also well form an all-over pattern; sometimes these lines used over a
surface are made to cross each other, tartan wise, by running in two
directions, producing an apparently complicated design by very simple
means.

[Illustration: Figs. 18 and 19.]

[Illustration: Fig. 20.]

Designs may be planned on the counterchange principle. This is a system
of mass designing that involves the problem of making a pattern out of
one shape, continually repeated, and fitting into itself in such a way
as to leave no interstices. The simplest example of this is to be found
in the chess board, and it will easily be seen that a great number of
shapes might be used instead of the square. Fig. 20 is an example of a
counterchange design carried out in inlay; for this method of work
counterchange is very suitable. On reference to the chapter upon this
work another example will be found (page 181). Fig. 21 illustrates the
same principle, further complicated by the repetition of the form in
three directions instead of in two only.

[Illustration: Fig. 21.]

A method of further enriching a straightforward pattern, covering a
plain surface, is to work a subsidiary pattern upon