Light XY, looks blue by the reflected Part of the Light, and red by the
transmitted Part of it, as when 'tis view'd in Day-light; but if you
intercept the blue at the Lens the Infusion will lose its reflected blue
Colour, whilst its transmitted red remains perfect, and by the loss of
some blue-making Rays, wherewith it was allay'd, becomes more intense
and full. And, on the contrary, if the red and orange-making Rays be
intercepted at the Lens, the Infusion will lose its transmitted red,
whilst its blue will remain and become more full and perfect. Which
shews, that the Infusion does not tinge the Rays with blue and red, but
only transmits those most copiously which were red-making before, and
reflects those most copiously which were blue-making before. And after
the same manner may the Reasons of other Ph nomena be examined, by
trying them in this artificial beam of Light XY.
FOOTNOTES:
[I] See p. 59.
[J] _See our_ Author's Lect. Optic. _Part_ II. _Sect._ II. _p._ 239.
[K] _As is done in our_ Author's Lect. Optic. _Part_ I. _Sect._ III.
_and_ IV. _and Part_ II. _Sect._ II.
[L] _See our_ Author's Lect. Optic. _Part_ II. _Sect._ II. _pag._ 269,
&c.
[M] _This is demonstrated in our_ Author's Lect. Optic. _Part_ I.
_Sect._ IV. _Prop._ 35 _and_ 36.
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