o follow some Pages
hence, more fully and particularly shew, that the Changes, and consequently
in divers places the Production and the appearance of Colours depends upon
the continuing or alter'd Texture of the Object, we shall in this place
intimate (and that too but as by the way) two or three things about this
Matter.

2. And first it is not without some Reason, that I ascribe Colour (in the
sense formerly explan'd) _chiefly_ to the Superficial parts of Bodies, for
not to question how much Opacous Corpuscles may abound even in those Bodies
we call Diaphanous, it seems plain that of Opacous bodies we do indeed see
little else than the Superficies, for if we found the beams of Light that
rebound from the Object to the Eye, to peirce deep into the Colour'd body,
we should not judge it Opacous, but either Translucid, or at least
Semi-diaphanous, and though the Schools seem to teach us that Colour is a
Penetrative Quality, that reaches to the Innermost parts of the Object, as
if a piece of Sealing-wax be broken into never so many pieces, the Internal
fragments will be as Red as the External surface did appear, yet that is
but a Particular Example that will not overthrow the Reason lately offer'd,
especially since I can alleage other Examples of a contrary Import, and two
or three Negative Instances are sufficient to overthrow the Generality of a
Positive Rule, especially if that be built but upon One or a Few Examples.
Not (then) to mention Cherries, Plums, and I know not how many other
Bodies, wherein the skin is of one Colour, and what it hides of another, I
shall name a couple of Instances drawn from the Colours of Durable bodies
that are thought far more Homogeneous, and have not parts that are either
Organical, or of a Nature approaching thereunto.

3 To give you the first Instance, I shall need but to remind you of what I
told you a little after the beginning of this Essay, touching the Blew and
Red and Yellow, that may be produc'd upon a piece of temper'd Steel, for
these Colours though they be very Vivid, yet if you break the Steel they
adorn, they will appear to be but Superficial; not only the innermost parts
of the Metall, but those that are within a hairs breadth of the
Superficies, having not any of these Colours, but retaining that of the
Steel it self. Besides that, we may as well confirm this Observation, as
some other particulars we elsewhere deliver concerning Colours, by the
following Experiment which