from your left, else the shadow of the pencil point
interferes with your sight of your work. You must not let the _sun_ fall
on the stone, but only ordinary light: therefore choose a window which
the sun does not come in at. If you can shut the shutters of the other
windows in the room it will be all the better; but this is not of much
consequence.

Now, if you can draw that stone, you can draw anything: I mean, anything
that is drawable. Many things (sea foam, for instance) cannot be drawn
at all, only the idea of them more or less suggested; but if you can
draw the stone _rightly_, every thing within reach of art is also within
yours.

For all drawing depends, primarily, on your power of representing
_Roundness_. If you can once do that, all the rest is easy and
straightforward; if you cannot do that, nothing else that you may be
able to do will be of any use. For Nature is all made up of roundnesses;
not the roundness of perfect globes, but of variously curved surfaces.
Boughs are rounded, leaves are rounded, stones are rounded, clouds are
rounded, cheeks are rounded, and curls are rounded: there is no more
flatness in the natural world than there is vacancy. The world itself is
round, and so is all that is in it, more or less, except human work,
which is often very flat indeed.

Therefore, set yourself steadily to conquer that round stone, and you
have won the battle.

Look your stone antagonist boldly in the face. You will see that the
side of it next the window is lighter than most of the paper: that the
side of it farthest from the window is darker than the paper; and that
the light passes into the dark gradually, while a shadow is thrown to
the right _on_ the paper itself by the stone: the general appearance of
things being more or less as in _a_, Fig. 5., the spots on the stone
excepted, of which more presently.

Now, remember always what was stated in the outset, that every thing you
can see in Nature is seen only so far as it is lighter or darker than
the things about it, or of a different colour from them. It is either
seen as a patch of one colour on a ground of another; or as a pale thing
relieved from a dark thing, or a dark thing from a pale thing. And if
you can put on patches of colour or shade of exactly the same size,
shape, and gradations as those on the object and its ground, you will
produce the appearance of the object and its ground. The best
draughtsman--Titian and Paul Veronese themselv