Oldal 173 [173]
COLOURS IN RIPPLED WATER 107
almost complementary hues reflected by the ripples
from differently coloured regions of the sky.
NOTE ON THE COLOUR OF SHADOWS
ON WATER.
IN the last chapter it was shown how in shadow the reflex¬
ions of objects are stronger than in sunlight, but this con¬
sideration alone does not seem sufficient to account for the
colours often observed. For instance, the shadow of a cloud
on the brilliant blue-green waters of an Alpine lake as
seen from a height appears of a distinctly pinkish or purple
tinge, and the same is true to a less extent of the shadows
of clouds seen at sea.
Most people, unless gifted with a very keen sense of colour,
find it difficult to define at all the colour of a shadow, and
indeed it is only when the eye has been trained by repeated
attempts at sketching that it begins to value at all correctly
the subtle gradations of tones in light and shade. More¬
over, the colour of objects is changed for the beholder
according to the conditions under which at the moment he
sees them. Ihus the patches of wet sand left by the ebbing
tide; though reflecting the pure blue of the sky, sometimes
appear greenish by contrast with the pink expanse of dry
sand surrounding them. Such an effect, which in nature is
produced by the mere juxtaposition of different tones, does
not, however arise from the juxtaposition of the lifeless pig¬
ments at our disposal. These are not luminous enough to
create it, and thus, to reproduce it on the canvas, the artist
has, perhaps unconsciously, to exaggerate the natural inter¬
vals of colour. We have said that it is generally difficult to
define the colour of a shadow, but there is one case in which
it is comparatively easy, namely, when the ground is entirely
covered with snow, so that all disturbing colours are removed.
On page 9 we referred to the irregular reflexion from the
surface of rough or unpolished objects, and pointed out how