Which Explication I propose, not that I think the Blackness of
the Velvet proceeds from the Cause assign'd, since each Single Pile of Silk
is Black by reason of its Texture, in what Position soever you Look upon
it; But that the Greater Blackness of one of these Tuffts seems to proceed
from the Greater Paucity of Beams Reflected from it, and that from the
Fewness of those Parts of a Surface that Reflect Beams, and the Multitude
of those Shaded Parts that Reflect none. And I remember, that I have
oftentimes observ'd, that the Position of Particular Bodies far greater
than Piles of Silk in reference to the Eye, may notwithstanding their
having each of them a Colour of its own, make one part of their Aggregate
appear far Darker than the other; For I have near Great Towns often taken
notice, that a Cart-load of Carrots pack'd up, appear'd of a much Darker
Colour when Look'd upon, where the Points of the Carrots were Obverted to
the Eye, than where the Sides of them were so.
7. Fourthly, In a Darkned Room, I purposely observ'd, that if the
Sun-beams, which came in at the Hole were receiv'd upon White or any other
Colour, and directed to a Convenient place of the Room, they would
Manifestly, though not all Equally, Encrease the Light of that Part;
whereas if we Substituted, either a piece of Black Cloth or Black Velvet,
it would so Dead the Incident Beams, that the place (newly mention'd)
whereto I Obverted the Black Body, would be Less Enlightned than it was
before, when it received its Light but from the Weak and Oblique
Reflections of the Floor and Walls of a pretty Large Room, through which
the Beams that came in at the Hole were Confusedly and Brokenly Dispers'd.
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