Oldal 157 [157]
OCR
COLOURS IN RIPPLED WATER 91 one that the colour of the water itself becomes more apparent under the new conditions; for the line of vision now strikes the surface more directly, (where it hits the near sides of the waves) than it would if the water were stl. In our previous diagrams we have represented the surface of a wave by means of a continuous curve, which nearly resembles the outline of a gentle ripple, but the billows of rougher water are covered with smaller waves whose crests rise up into cusps or points, thus: NM Bi RTE pet CON so that they present surfaces nearly perpendicular to the direction of vision, which, as shown in the previous chapter, is the position most favourable for seeing the colour of water. For of course it is the same thing whether we change our position so as to look more directly at the level surface of still water, or whether the surface of the water be inclined so as to face more fully our line of vision. The conditions are exceedingly complicated. The eye is bewildered by light reflected from a great part of the sky by countless moving facets, and the dancing waves seem to mock our feeble attempts at analysis. But it will nevertheless help us to bear this principle in mind; and knowing that the more abruptly we look at the surface of the water, the more we may expect to see of its true colour, we shall be the better able to distinguish this colour wherever it appears from that due to reflexion. Anyone who has stood on the sea beach is aware that in the curl of a wave breaking towards him the colour of the water is plainly visible, tag I apie EC a oe. NÉZ
