Diagram IX.
ILLUSTRATING VARIETY IN SYMMETRY
Note how the hollows marked A are opposed by the fullnesses marked B.
Of course the student, if he has any natural ability, instinctively looks out for all these variations that give the play of life to his drawing. It is not for him in the full vigour of inspiration that books such as this are written. But there may come a time when things "won't come," and it is then that it is useful to know where to look for possible weak spots in your work.
Variety of Thickness and Accent.
A line of equal thickness is a very dead and inexpressive thing compared with one varied and stressed at certain points. If you observe any of the boundaries in nature we use a line to express, you will notice some points are accentuated, attract the attention, more than others. The only means you have to express this in a line drawing is by darkening and sharpening the line. At other points, where the contour is almost lost, the line can be soft and blurred.
It is impossible to write of the infinite qualities of variety that a fine draughtsman will get into his line work; they must be studied first hand. But on this play of thickness and quality of line much of the vitality of your drawing will depend.