The vista, as said above, rivets and confines the attention.  We can, therefore, understand how it is that in the genre table it suddenly appears very numerous.  The active character of these pictures naturally requires to be modified, and the vista introduces a powerful balancing element, which is yet quiet; or, it might be said, inasmuch as energy is certainly expended in plunging down the third dimension, the vista introduces an element of action of counterbalancing character.  In the landscape it introduces the principal element of variety.  It is always to be found in those parts of the picture which are opposed to other powerful elements, and the ‘heavier’ the other side, the deeper the vista.  This is especially to be noted in all pictures of the S. & S. type, where the one side is very ‘heavy’ and the deep vista practically invariable on the other.  Also in D.C. pictures it serves as a kind of fulcrum, or unifying element, inasmuch as it rivets the attention between the two detached sides. (Cf.  D.C. among Alt. and Mad.)

The direction of suggestion by means of the indication of a line (L.), quite naturally is more frequent in the Madonna-picture and Portrait classes.  Both these types are of large simple outline, so that L. would be expected to tell, but more or less irregular, so that it would not appear on both sides, thus neutralizing its action, as often in the symmetrical altarpieces.  This neutralizing explains why it has a comparatively small per cent. in the landscape table, it having appeared in minor form all over the field, but less often in large salient outline.  It is worth noticing that for the D.C. of both genre and landscape, the per cent. drops appreciably.  As it is, in a decided majority of cases, combined with V.—­the shape being more or less a diagonal slope—­it is clear that it acts as a kind of bond between the two sides, carrying the attention without a break from one to the other.

The element of mass requires less comment.  It appears in greatest number in those pictures which have little action, portraits and landscapes, and which are yet not symmetrical—­in which last case mass is, of course, already balanced.  In fact, it must of necessity exert a certain influence in every unsymmetrical picture, and so its percentage, even for genre pictures, is large.

Thus we may regard the elements as both attracting attention to a certain spot and dispersing it over a field.  Those types which are of a static character abound in elements which disperse the attention; those which are of a dynamic character, in those which make it stable.  The ideal composition seems to combine the dynamic and static elements—­to animate, in short, the whole field of view, but in a generally bilateral fashion.  The elements, in substitutional symmetry, are then simply means of introducing variety and action.  As a dance in which there are complicated steps gives the actor and beholder a varied and thus vivified ‘balance,’ and is thus more beautiful than the simple walk, so a picture composed in substitutional symmetry is more rich in its suggestions of motor impulse, and thus more beautiful, than an example of geometrical symmetry.