The next thing to be sought is Variety. Too obvious or positive a
scheme, while possibly not unsuitable for a conventional decorative
drawing, may not be well adapted to a perspective subject. The
large color areas should be echoed by smaller ones throughout the
picture. Take, for example, the Vierge drawing shown in Fig. 26.
Observe how the mass of shadow is relieved by the two light holes
seen through the inn door. Without this repetition of the white the
drawing would lose much of its character. In Rico's drawing, Fig.
11, a tiny white spot in the shadow cast over the street would, I
venture to think, be helpful, beautifully clear as it is; and the
black area at the end of the wall seems a defect as it competes
in value with the dark figure.

[Illustration: FIG. 26 DANIEL VIERGE]

[Side note: _Breadth of Effect_]

Lastly, Breadth of Effect has to be considered. It is requisite
that, however numerous the tones are (and they should not be too
numerous), the general effect should be simple and homogeneous. The
color must count together broadly, and not be cut up into patches.

[Illustration: FIG. 27 HARRY FENN]

It is important to remember that the gamut from black to white is
a short one for the pen. One need only try to faithfully render
the high lights of an ordinary table glass set against a gray
background, to be assured of its limitations in this respect. To
represent even approximately the subtle values would require so