Stranica 154 [154]
OCR
90 LIGHI AND WATER oloomy colour, assuming in response a dark and threatening aspect. It sometimes happens that there is a high bank of dark clouds rising up Írom the horizon, and overhead a lighter region, in which case the less common effect of the rippled surface appearing lighter than the smooth may be given. ‘lowards sunset, in the same way, the oily-looking streaks of smooth water in a very calm sea often appear yellow or orange by contrast with the more rippled—and therefore bluer—surface surrounding them, reflecting, as they do, a lower part of the sky where warmer tones predominate. Plates XX XVIII and XXXIX are photographs illustrative of this point. In the upper view, taken at the narrow mouth of a West Highland loch, the tide is flowing rapidly in a strong current from the left. The wind (also from the west) ruffles the mass of the water, but leaves the surface of the current, travelling in the same direction as itself, comparatively smooth. So that, while the greater part of the water reflects ‘the sky, the path of the current reflects the hillside and thus becomes conspicuous as a dark stream winding its way through the lighter ripple. There is also a patch of smoother and therefore dark-looking water under the lee of the island on the left. The lower view shows an effect of the same nature, but with the opposite result. The whole surface of the water is ruffled, some parts of it more than others. In this case the smoother portion reflects chiefly light from the low bright region of the sky, whilst the rougher portion reflects the darker clouds above. But, in addition to this effect, we have the further
