180 
NATURE FOR ITS OWN SAKE 
Local hue 
and 
rejlection. 
grass may decide the coloring of a shadow fall- 
ing uponit. Pure water is in itself a most ex- 
quisite and subtle blue, but spread over a bed 
of yellow sand under sunlight it may appear 
yellow or perhaps greenish in hue. Even when 
the water is too deep to see the bottom, the 
latter may have some determining influence on 
the color by mingling with or illuminating it. 
Reflection is, however, the more powerful 
factor in leading us astray as regards local hue. 
Smooth water, ike a mirror, is always throwing 
back from its face some likeness in light, form, 
and color of whatever happens to be above it, 
be it rock, tree, bank, or sky. The water may 
be green in, let us say Lake Placid, but the re- 
flection of the clear sky from its face makes it 
appear blue. Even when the surface is agi- 
tated and the reflection is broken, there is always 
more or less flashing hght from the sky along the 
tiny facets on the backs of the waves. We can 
only get the local hue by shutting out the re- 
flected hue. A gray sky with a rutied surface 
dispels or breaks reflection sufficiently to give 
us some notion of local color ; and it is during 
rain-storms and squally weather on sea, lake, 
and river that we gain the truest knowledge of 
the actual colors of waters. Sometimes, under 
