be slugged or
stopped by the tinging particles E, F, G, H; therefore there shall be
_secundary_ and weak pulse that shall follow the Ray, namely PP which will
be the weaker: first, because it has suffer'd many refractions in the
impeding body; next, for that the Rays will be a little dispers'd or
confus'd by reason of the refraction in each of the particles, whether
_round_ or _angular_; and this will be more evident, if we a little more
closely examine any one particular tinging _Globule_.
Suppose we therefore AB in the eighth _Figure_ of the sixth _Scheme_, to
represent a tinging _Globule_ or particle which has a greater refraction
than the liquor in which it is contain'd: Let CD be a part of the pulse of
light which is _propagated_ through the containing _medium_; this pulse
will be a little stopt or impeded by the _Globule_, and so by that time the
pulse is past to EF that part of it which has been impeded by passing
through the _Globule_, will get but to LM, and so that pulse which has been
_propagated_ through the _Globule_, to wit, LM, NO, PQ, will always come
behind the pulses EF, GH, IK, &c.
Next, by reason of the greater impediment in AB, and its _Globular_ Figure,
the Rays that pass through it will be dispers'd, and very much scatter'd.
Whence CA and DB which before went _direct_ and _parallel_, will after the
refraction in AB, _diverge_ and spread by AP, and BQ; so that as the Rays
do meet with more and more of these tinging particles in their way, by so
much the more will the pulse of light further lagg behind the clearer
pulse, or that which has fewer refractions, and thence the deeper will the
colour be, and the fainter the light that is trajected through it; for not
onely many Rays are reflected from the surfaces of AB, but those Rays that
get through it are very much disordered.
By this _Hypothesis_ there is no one experiment of colour that I have yet
met with, but may be, I conceive, very rationably solv'd, and perhaps, had
I time to examine several particulars requisite to the demonstration of it,
I might prove it more than probable, for all the experiments about the
changes and mixings of colours related in the Treatise of Colours,
published by the _Incomparable_ Mr. _Boyle_, and multitudes of others which
I have observ'd, do so easily and naturally flow from those principles,
that I am very apt to think it probable, that they own their production to
no other _secundary_ cause: As to instance in
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