s admitted, a Sheet only of White Paper, from whence casting the
Sun-beams upon a White Wall, whereunto it was Obverted, it manifestly
appear'd both to Me, and to the Person I took for a Witness of the
Experiment, that it Reflected a far greater Light, than any of the other
Colours formerly mention'd, the Light so thrown upon one Wall notably
Enlightning it, and by it a good part of the Room. And yet further to show
you, that White Bodies Reflect the Beams From them, and not Towards
themselves, Let me add, that Ordinary Burning-glasses, such as are wont to
be employ'd to light Tobacco, will not in a great while Burn, or so much as
Discolour a Sheet of White Paper. Insomuch that even when I was a Boy, and
Lov'd to make Tryals with Burning-glasses, I could not but wonder at this
Odd _Phaenomenon_, which set me very Early upon Guessing at the Nature of
Whiteness, especially because I took notice, that the Image of the Sun upon
a White Paper was not so well Defin'd (the Light seeming too Diffus'd) as
upon Black, and because I try'd, that Blacking over the Paper with Ink, not
only the Ink would be quickly Dry'd up, but the Paper that I could not Burn
before, would be quickly set on Fire. I have also try'd, that by exposing
my Hand with a Thin Black Glove over it to the Warm Sun, it was thereby
very quickly and considerably more Heated, than if I took off the Glove,
and held my Hand Naked, or put on it another Glove of Thin but White
Leather. And having thus shewn you, _Pyrophilus_, that White Bodies reflect
the most Light of any, let us now proceed, to consider what is further to
be taken notice of in them, in order to our present Enquiry.
8. And Fourthly, whereas among the Dispositions we attributed to White
Bodies, we also intimated this, That such Bodies are apt, like _Speculums_,
though but Imperfect ones, to Reflect the Light that falls on them
Untroubled or Unstain'd, we shall besides other particulars to be met with
in these Papers, offer you this in favour of the Conjecture; That in the
Darkned Room several times mention'd in this Treatse, we try'd that the
Sun-beams being cast from a Coloured Body upon a neighbouring White Wall,
the Determinate Colour of the Body was from the Wall reflected to the Eye;
whereas we could in divers cases manifestly Alter the Colour arriving at
the Eye, by Substituting at a convenient Distance, a (conveniently)
Colour'd (and Glossy) Body instead of the White Wall. As by throwing the
Beam
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