reflected from them, that is, Rays unting'd, which are onely reflected from
the outward surface, without at all penetrating of the body, and ting'd
Rays which are reflected from the inward surfaces or flaws after they have
suffer'd a two-fold refraction; and because that transparent liquors mixt
with such _corpuscles_, do, for the most part, take off the former kind of
reflection; therefore these colours mixt with Water or Oyl, appear much
deeper than when dry, for most part of that white reflection from the
outward surface is remov'd. Nay, some of these colours are very much
deepned by the mixture with some transparent liquor, and that because they
may perhaps get between those two flaws, and so consequently joyn two or
more of those flaw'd pieces together; but this happens but in a very few.

Now, to shew that all this is not _gratis dictum_, I shall set down some
Experiments which do manifest these things to be probable and likely, which
I have here deliver'd.

For, first, if you take any ting'd liquor whatsoever, especially if it be
pretty deeply ting'd, and by any means work it into a froth, the
_congeries_ of that froth shall seem an _opacous_ body, and appear of the
same colour, but much whiter than that of the liquor out of which it is
made. For the abundance of reflections of the Rays against those surfaces
of the bubbles of which the froth consists, does so often rebound the Rays
backwards, that little or no light can pass through, and consequently the
froth appears _opacous_.

Again, if to any of these ting'd liquors that will endure the boiling there
be added a small quantity of fine flower (the parts of which through the
_Microscope_ are plainly enough to be perceiv'd to consist of transparent
_corpuscles_) and suffer'd to boyl till it thicken the liquor, the mass of
the liquor will appear _opacous_, and ting'd with the same colour, but very
much whiten'd.

Thus, if you take a piece of transparent Glass that is well colour'd, and
by heating it, and then quenching it in Water, you flaw it all over, it
will become _opacous_, and will exhibit the same colour with which the
piece is ting'd, but fainter and whiter.

Or, if you take a Pipe of this transparent Glass, and in the flame of a
Lamp melt it, and then blow it into very thin bubbles, then break those
bubbles, and collect a good parcel of those _laminae_ together in a Paper,
you shall find that a small thickness of those Plates will constitute an
_opac