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Boyle, Robert, 1627-1691

"Experiments and Considerations Touching Colours (1664)"

And I have sometimes for Tryals
sake brought in by a Lenticular Glass, the Image of a River, Shin'd upon by
the Sun, into an Upper Room Darkn'd, and Distant about a Quarter of a Mile
from the River, by which means the Numerous Declining Surfaces of the Water
appear'd so Contracted, that upon the Body that receiv'd the Images, the
whole River appear'd a very White Object at two or three paces distance.
But if we drew Near it, this Whiteness appear'd to proceed from an
Innumerable company of Lucid Reflections, from the several Gently wav'd
Superficies of the Water, which look'd Near at hand like a Multitude of
very Little, but Shining Scales of Fish, of which many did every moment
Disappear, and as many were by the Sun, Wind and River generated anew. But
though this Observation seem'd Sufficiently to discover, how the Appearing
Whiteness in that case was Produc'd, yet in some other cases Water may have
the Same, though not so Vivid a Colour upon other Accounts; for oftentimes
it happens that the Smooth Surface of the Water does appear Bright or
Whitish, by reason of the Reflection not immediatly of the Images of the
Sun, but of the Brightness of the Sky; and in such cases a Convenient Wind
may where it passes along make the Surface look Black, by causing many such
Furrows and Cavities, as may make the Inflected Superficies of the Water
reflect the Brightness of the Sky rather Inward than Outward.


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