After point 3 there would be no light coming to the eye from the object, were it not that it receives reflected light.  Now, the greatest amount of reflected light will come from the direction opposite to that of the direct light, as all objects in this direction are strongly lit.  The surface of the wall between points E and H, being directly opposite the light, will give most reflection.  And between points 5 and 6 this light will be reflected by the cone to the eye in its greatest intensity, since at these points the angles of incidence equal the angles of reflection.  The other parts of the shadow will receive a certain amount of reflected light, lessening in amount on either side of these points.  We have now rays of light coming to the eye from the cone between the extreme points 7 and 8.  From 7 to 3 we have the light, including the half tones.  Between 1 and 2 the high light.  Between 3 and 8 the shadows, with the greatest amount of reflected light between 5 and 6.

[Illustration:  Plate XIX.

ILLUSTRATING CURVED LINKS SUGGESTING FULLNESS AND FORESHORTENING]

I should not have troubled the reader with this tedious diagram were it not that certain facts about light and shade can be learned from it.  The first is that the high lights come much more within the edge of the object than you would have expected.  With the light directly opposite point 7, one might have thought the highest light would have come there, and that is where many students put it, until the loss of roundness in the appearance of their work makes them look more carefully for its position.  So remember always to look out for high lights within the contours of forms, not on the edges.

The next thing to notice is that #the darkest part of the shadow will come nearest the lights between points 3 and 5#.  This is the part turned most away from the direction of the greatest amount of reflected light, and therefore receiving least.  The lightest part of the shadow will be in the middle, rather towards the side away from the light, generally speaking.  The shadow cast on the ground will be dark, like the darkest part of the shadow on the cone, as its surface is also turned away from the chief source of reflected light.

Although the artist will very seldom be called upon to draw a cone, the same principles of light and shade that are so clearly seen in such a simple figure obtain throughout the whole of nature.  This is why the much abused drawing and shading from whitened blocks and pots is so useful.  Nothing so clearly impresses the general laws of light and shade as this so-called dull study.