great enemies of colour, sullying, as they do, its purity; and to some extent to design also, destroying, as they do, the flatness of the picture.  But with the strong direct light, the masses are cut out as simply as possible, and their colour is little sullied by light and shade.  The picture of Manet’s reproduced is a typical example of his manner.  The aggressive shape of the pattern made by the light mass against the dark background is typical of his revolutionary attitude towards all accepted canons of beauty.  But even here it is interesting to note that many principles of composition are conformed to.  The design is united to its boundaries by the horizontal line of the couch and the vertical line of the screen at the back, while the whole swing hangs on the diagonal from top left-hand corner to right; lower corner, to which the strongly marked edge of the bed-clothes and pillow at the bottom of the picture is parallel.

[Illustration:  Plate XLV.

CORREGGIO.  VENUS.  MERCURY, AND CUPID (NATIONAL GALLERY)

A fine example of one of the most effective tone arrangements; a brilliantly-lit, richly-modelled light mass on a dark background.

Photo Hanfstaengl]

Large flat tones give a power and simplicity to a design, and a largeness and breadth of expression that are very valuable, besides showing up every little variety in the values used for your modelling; and thus enabling you to model with the least expenditure of tones.  Whatever richness of variation you may ultimately desire to add to your values, see to it that in planning your picture you get a good basic structure of simply designed, and as far as possible flat, tones.

In speaking of variety in mass we saw how the #nearer these tones are in the scale of values, the more reserved and quiet the impression created#, and the #further apart or greater the contrast, the more dramatic and intense the effect#.  And the sentiment of tone in a picture, like the sentiment of line and colour, should be in harmony with the nature of your subject.

Generally speaking #more variety of tone and shape in the masses of your composition is permissible when a smaller range of values is used than when your subject demands strong contrasts#.  When strong contrasts of tone or what are called black and white effects are desired, the masses must be very simply designed.  Were this not so, and were the composition patterned all over with smaller masses in strong contrast, the breadth and unity of the effect would be lost.  While when the difference of relative values between one tone and another is slight, the oneness of effect is not so much interfered with by there being a large number of them.  Effects of strong contrasts are therefore far the most difficult to manage, as it is not easy to reduce a composition of any complexity to a simple expressive pattern of large masses.