Page 136 [136]
76 LIGHT AND WATER
reflecting as it does at this abrupt angle so much less
light from the sky, is considerably below the value of
that part of the sky which it reflects. One hears it
said that water should be painted "a tone lower”
than the sky. As a matter of fact, they are in the
distance almost equal in value; whilst, on looking
down perpendicularly at the water, the difference in
value between them is enormous, the blue sky ap¬
pearing almost black by reflexion. Thus there is a
marked gradation in (diminishing) value from the far
distance to the foreground, increased by the fact that
the upper parts of the sky are darker than those near
the horizon. This gradation may be clearly seen in
any photograph which includes a water foreground,
as, for instance, in the frontispiece to this volume.’
So much for the angle of vision; but the degree
of illumination is also an important condition. It has
been already noted (page 68) how the colour of water
is brought out by direct sunlight, and the difference in
the appearance of our duck-pond in sunshine and in
shade is very considerable. On adull day, the colour
of the water may perhaps be scarcely perceptible a
yard or two from the point at which the observer is
standing, and looking more obliquely on to the water,
it disappears altogether, so that at the further side of
the pond the sky seems to be mirrored in all its purity
' Owing to the limited range of luminosity in a photograph, the
brightest part of the sky in this view appears no brighter than its
reflexion, though the actual difference in tone must have been as
great there as in the darker parts of the sky on either side of it. A
more natural effect might possibly have been obtained by cutting
. away the mesh in this block in the brightest part of the sky.