Stranica 53 [53]
REFLEXIONS IN RIPPLED WATER 29
is looking from E at the surface of the near wave at
A. In order to find the direction of his line of vision
after reflexion, we may suppose there to be a tiny
mirror floating on the surface of the water at A; this
mirror will be tipped up towards him, and his line of
vision will be along AB (the angle of reflexion being
equal to the angle of incidence, as explained in the
last chapter), whereas, if the water had been smooth,
he would have been looking on the level surface at
C, and his line of vision would have taken the direc¬
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Dic...
Fig. 12. Lines of vision, on striking the near sides of the
waves, deflected towards the sky.
tion CD. (The dotted lines represent the condition
in smooth water.) Ihere are of course points on
the surface even when the water is disturbed, as,
for instance, on the crest of a wave at F, where a
floating mirror would assume a horizontal position,
but it is evident from the figure that in the great
majority of cases the line of vision strikes a surface
inclined fowards the observer, and is therefore re¬
flected up towards the sky, in some cases less, in
others more. The result is that it is only at certain
comparatively minute spots that we catch sight of
the image that would appear in smooth water, these
spots being surrounded by surfaces reflecting the sky