kind of sketch to
mark the facts clearly. The temptation is always to be slovenly and
careless, and the outline is like a bridle, and forces our indolence
into attention and precision. The outline should be about the thickness
of that in Fig. 4, which represents the ramification of a small stone
pine, only I have not endeavoured to represent the pencil shading within
the outline, as I could not easily express it in a woodcut; and you have
nothing to do at present with the indication of the foliage above, of
which in another place. You may also draw your trees as much larger
than this figure as you like; only, however large they may be, keep the
outline as delicate, and draw the branches far enough into their outer
sprays to give quite as slender ramification as you have in this figure,
otherwise you do not get good enough practice out of them.

[Illustration: FIG. 4.]

You cannot do too many studies of this kind: every one will give you
some new notion about trees: but when you are tired of tree boughs, take
any forms whatever which are drawn in flat colour, one upon another; as
patterns on any kind of cloth, or flat china (tiles, for instance),
executed in two colours only; and practice drawing them of the right
shape and size by the eye, and filling them in with shade of the depth
required.

In doing this, you will first have to meet the difficulty of
representing depth of colour by depth of shade. Thus a pattern of
ultramarine blue will have to be represented by a darker tint of grey
than a pattern of yellow.

And now it is both time for you to begin to learn the mechanical use of
the brush, and necessary for you to do so in order to provide yourself
with the gradated scale of colour which you will want. If you can, by
any means, get acquainted with any ordinarily skilful water-colour
painter, and prevail on him to show you how to lay on tints with a
brush, by all means do so; not that you are yet, nor for a long while
yet, to begin to colour, but because the brush is often more convenient
than the pencil for laying on masses or tints of shade, and the sooner
you know how to manage it as an instrument the better. If, however, you
have no opportunity of seeing how water-colour is laid on by a workman
of any kind, the following directions will help you:--

EXERCISE VII.

Get a shilling cake of Prussian blue. Dip the end of it in water so as
to take up a drop, and rub it in a white saucer till you cannot rub m