Oldal 157 [157]
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 con¬
tinuous 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,
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