y deep mixture of Saffron, and that every one of them did
appear of a deep Scarlet colour, and all of them together did _exhibit_ at
a distance, a deep dy'd Scarlet body. It does not follow, because after we
have come nearer to this _congeries_, or mass, and divided it into its
parts, and examining each of its parts severally or apart, we find them to
have much the same colour with the whole mats; it does not, I say,
therefore follow, that if we could break those _Globules_ smaller, or any
other ways come to see a smaller or thinner parcel of the ting'd liquor
that fill'd those bubbles, that that ting'd liquor must always appear Red,
or of a Scarlet hue, since if Experiment be made, the quite contrary will
ensue; for it is capable of being _diluted_ into the palest Yellow.

Now, that I might avoid all the Objections of this kind, by exhibiting an
Experiment that might by ocular proof convince those whom other reasons
would not prevail with, I provided me a _Prismatical Glass_, made hollow,
just in the form of a Wedge, such as is represented in the tenth _Figure_
of the sixth _Scheme_. The two _parallelogram_ sides ABCD, ABEF, which met
at a point, were made of the clearest Looking-glass plates well ground and
polish'd that I could get; these were joyn'd with hard cement to the
_triangular_ sides, BCE, ADF, which were of Wood; the _Parallelogram_ base
BCEF, likewise was of Wood joyn'd on to the rest with hard cement, and the
whole _Prismatical_ Box was exactly stopt every where, but onely a little
hole near the base was left, whereby the Vessel could be fill'd with any
liquor, or emptied again at pleasure.

One of these Boxes (for I had two of them) I fill'd with a pretty deep
tincture of _Aloes_, drawn onely with fair Water, and then stopt the hole
with a piece of Wax, then, by holding this Wedge against the Light, and
looking through it, it was obvious enough to see the tincture of the liquor
near the edge of the Wedge where it was but very thin, to be a pale but
well colour'd Yellow, and further and further from the edge, as the liquor
grew thicker and thicker, this tincture appear'd deeper and deeper, so that
near the blunt end, which was seven Inches from the edge and three Inches
and an half thick; it was of a deep and well colour'd Red. Now, the clearer
and purer this tincture be, the more lovely will the deep Scarlet be, and
the fouler the tincture be, the more dirty will the Red appear; so that
some dirty tinctur