44. Fourth. The movement in [Fig. 44] may be increased by a diminution of scale and consequent crowding together of the dots, provided the movement of the groups and the crowding together have the same direction.
Fig. 45
In this case, as I have said, the movement of [Fig. 44] is enforced by the presence of another element of movement, that of a gradation of scale and consequent crowding together in the groups. The two movements have the same direction. The movement of the crowding is not so strong as that which is caused by the instability of the group itself.
45. Fifth. A symmetrical relation of positions, being repeated in a series with gradually diminishing intervals between the repeats, will give us a feeling of rhythmic movement. It will be due to a gradual increase in the number of attractions as the eye passes from one angle of vision to another. [See Fig. 41]. The Rhythm will, no doubt, be somewhat retarded by the sense of successive axes of symmetry.
Fig. 46
In this case a symmetrical group is repeated in a progression of measures. The movement is toward the greater number of attractions at the right end of the series. This increase in the number of attractions is due simply to diminishing intervals in that direction. The eye moves through a series of angles toward the angle which contains the greatest number of attractions. The reader can hardly fail to feel the successive axes of symmetry as a retarding element in this Rhythm.
46. Sixth. Symmetrical relations of position may be repeated in progressions of scale and of intervals. In that case we get two movements, one caused by a gradual increase in the number of attractions in successive angles of vision, the other being due to a gradual crowding together and convergence of attractions in the same series of angles.
