Oldal 173 [173]
OCR
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 reflexions of objects are stronger than in sunlight, but this consideration 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. Moreover, 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 pigments 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 intervals 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
