Now this is certainly, in a general way, the meaning of the word tone. So, although the word itself is new to you, the idea contained in it is not. We have talked a good deal about color-relations, rhythm, and harmony. You remember our talk on Vermeer’s picture. Well, his is a tonal picture, because of the perfect relation of all the colors to one another. It is beautiful in tone; its tonality is exquisite. And do you remember one particular feature of its exquisiteness? I pointed out to you that it is full of lighted atmosphere, and that the atmosphere seems to vibrate; that its rhythm passes through and through the picture, uniting all the masses of color into a harmonious whole. We noted the difference between this kind of rhythm and that in Raphael’s _Jurisprudence_, where the rhythm is the result of line. You could not describe that picture as tonal; for in it color plays a very unimportant part. Raphael was busied with the relations, not of color, but of line.