In almost all compositions a rhythmic flow of lines can be traced.  Not necessarily a flow of actual lines (although these often exist); they may be only imaginary lines linking up or massing certain parts, and bringing them into conformity with the rhythmic conception of the whole.  Or again, only a certain stress and flow in the forms, suggesting line movements.  But these line movements flowing through your panel are of the utmost importance; they are like the melodies and subjects of a musical symphony, weaving through and linking up the whole composition.

Often, the line of a contour at one part of a picture is picked up again by the contour of some object at another part of the composition, and although no actual line connects them, a unity is thus set up between them. (See diagrams, pages 166 and 168, illustrating line compositions of pictures by Botticelli and Paolo Veronese).  This imaginary following through of contours across spaces in a composition should always be looked out for and sought after, as nothing serves to unite a picture like this relationship of remote parts.  The flow of these lines will depend on the nature of the subject:  they will be more gracious and easy, or more vigorous and powerful, according to the demands of your subject.

This linking up of the contours applies equally well to the drawing of a single figure or even a head or hand, and the student should always be on the look out for this uniting quality.  It is a quality of great importance in giving unity to a composition.

[Sidenote:  Parallelism]

When groups of lines in a picture occur parallel to each other they produce an accentuation of the particular quality the line may contain, a sort of sustained effect, like a sustained chord on an organ, the effect of which is much bigger than that of the same chord struck staccato.  This sustained quality has a wonderful influence in steadying and uniting your work.

This parallelism can only be used successfully with the simplest lines, such as a straight line or a simple curve; it is never advisable except in decorative patterns to be used with complicated shapes.  Blake is very fond of the sustained effect parallelism gives, and uses the repetition of curved and straight lines very often in his compositions.  Note in Plate I of the Job series, page 146 [Transcribers Note:  Plate XXXI], the use made of this sustaining quality in the parallelism of the sheep’s backs in the background and the parallel upward flow of the lines of the figures.  In Plate II you see it used in the curved lines of the figures on either side of the throne above, and in the two angels with the scroll at the left-hand corner.  Behind these two figures you again have its use accentuating by repetition the peaceful line of the hacks of the sheep.  The same thing can be seen in Plate XXXI, B, where the parallelism of the back lines of the sheep and the legs of the seated figures gives a look of peace