size of the first; and, if the third be removed the same distance from
the second, it will appear _two-thirds_ less; and so on they will
diminish in equal proportion. At twice the distance, it will diminish
_three-fourths_; and at one-third more, it will lose _five-sixths_; and
so retire progressively, never varying the point of sight. One eye only
should be open, in order to reduce all objects to one point of sight;
the objects immediately in front, receiving alone the highest finish,
that all may appear to have ground to stand on. If you look at nature
with both eyes, you will never obtain the same relief upon a flat
superfice.

The horizontal line should never be placed at _half_ the height of the
picture, but always above or below it.

In drawing a room, or the nave of a church, place the centre of it on
one _side_, and never in the middle; and nearer the _bottom_ than the
top. Observe the same rule with the figures. One side should be in
light, while the other is in shadow. The heads or parts of figures on
the shadowed side should catch the light; while, to balance the mass,
the dark groups should be placed on the light side. (_See plate 1, fig.
1._)

So, in drawing any single object, always place it sufficiently on _one
side_, to procure a greater space above it, than beneath; and more
repose on _one_ side than the _other_. This principle should never be
lost sight of, for even in portraits it has a bad effect.

To produce pictorial effect, in composing landscape, the lines should be
of unequal length, forming acute and obtuse angles. Neither should they
be vertical or horizontal with the sides or bottom of the square, but
always diagonal, the distant horizon and lower streaks of the bases of
the clouds excepted, which should be contrasted, by the upper parts of
the clouds being round. Broken banks and spreading roots of trees will
effect this. An exception, in buildings and architecture, something
reverses this rule, from the lines being perpendicular and horizontal,
in which case, the shadows must be diagonal. When a wall, for instance,
is _straight_, a wheel, or circular object is generally placed against
it, to reverse the lines by apposition.'

'Objects, whether they consist of lights, shadows, or figures, must be
disposed in large _masses_ and groups, properly varied and contrasted,
that, to a certain quantity of action, a proportioned space of plain
ground is required; that light is to be supported by