A moment ago I spoke of the picture as being like a melody. It will suggest to some imaginations the blitheness of a spring-song. The fact that a painting may sometimes seem to have the tunefulness or harmony of music I have already mentioned in a previous chapter. The reason is that painting and music, although different arts, have certain elements in common. Later on, when we shall speak of color, I shall try to suggest to you the correspondence between sound notes in music and color notes in painting. But for the present I will remind you of an element, common to both arts, of which we have already spoken--rhythm. In Raphael’s _Jurisprudence_, I pointed out to you the rhythm of movement in the figures. It flows through the forms of the figures in rippling, wave-like lines of direction. But nothing of that sort is apparent in Vermeer’s picture. There are repetitions and contrasts in the arrangement of the full and empty spaces; but they represent rather a pattern of spots; we are not conscious of any rhythm of line. Then, in what does the rhythm consist?