Stranica 77 [77]
OCR
REFLEXIONS IN RIPPLED WATER 43 Yet this fact did not prevent the formation of vertical streaks. If the strongly illuminated portions of the little waves are closely examined in the original photograph, they are found each to consist of a number of minute spots of light, which no doubt represent surfaces turned towards the sun. The experiment described above also shows how, when the ripples are very reocular and travelling obliguely to the direction of sight, the streaks formed by reflexion, instead of being vertical, may slope a little to one side or the other. But it will be noticed that the streak in Pig 370 is oaly ——-——— siete : slightly inclined, and Fig. 17c. Glass turned through a right is far from having angle from its first position. reached a position (viz., PQ) at right angles to the lines of grease. In nature this effect, except on the surfaces of the nearer waves, is so unusual and inconsiderable, that in a picture it might give an appearance of careless drawing. In the foreground, however, we sometimes get strange effects of distortion or bending of the image, as, for instance, in the smooth waves in the wash of. a boat moving through calm water.
