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Boyle, Robert, 1627-1691

"Experiments and Considerations Touching Colours (1664)"

First, That as I lately said, Whiteness and Blackness being generally
reputed to be Contrary Qualities, Whiteness depending as I said upon the
Disposition of the Parts of a Body to Reflect much Light, it seems likely,
that Blackness may depend upon a Contrary Disposition of the Black Bodies
Surface; But upon this I shall not Insist.
4. Next then we see, that if a Body of One and the same Colour be plac'd,
part in the Sun-beams, and part in the Shade, that part which is not Shin'd
on will appear more of Kin to Blackness than the other, from which more
Light Rebounds to the Eye; And Dark Colours seem the Blacker, the less
Light they are Look'd upon in, and we think all Things Black in the Dark,
when they send no Beams to make Impressions on our Organs of Sight, so that
Shadows and Darkness are near of Kin, and Shaddow we know is but a
Privation of Light; and accordingly Blackness seems to proceed from the
Paucity of Beams Reflected from the Black Body to the Eye, I say the
Paucity of Beams, because those Bodies that we call Black, as Marble, Jeat,
&c. are Short of being perfectly so, else we should not See them at all.
But though the Beams that fall on the Sides of those Erected Particles that
we have been mentioning, do Few of them return Outwards, yet those that
fall upon the Points of those Cylinders, Cones, or Pyramids, may thence
Rebound to the Eye, though they make there but a Faint Impression, because
they Arrive not there, but Mingl'd with a great Proportion of Little
Shades.


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