9 Wherefore, I shall now add, that some years before, a person exceedingly eminent for his profound Skil in almost all kinds of Philological Learning, coming to advise with mee about a Distemper in his Eyes, told me, among other Circumstances of it, that, having upon a time looked too fixedly upon the Sun, thorow a Telescope, without any coloured Glass, to take off from the dazling splendour of the Object, the excess of Light did so strongly affect his Eye, that ever since, when he turns it towards a Window, or any White Object, he fancies, he seeth a Globe of Light, of about the bigness the Sun then appeared of to him, to pass before his Eyes: And having Inquir'd of him, how long he had been troubled with this Indisposition, he reply'd, that it was already nine or ten years, since the Accident, that occasioned it, first befel him.
I could here subjoyn, Pyrophilus, some memorable Relations that I have met with in the Account given us by the experienc'd Epiphanius Ferdinandus, of the Symptomes he observ'd to be incident to those that are bitten with the Tarantula, by which (Relations) I could probably shew, that without any change in the Object, a change in the Instruments of Vision may for a great while make some Colours appear Charming, and make others Provoking, and both to a high degree, though neither of them produc'd any such Effects before. These things, I say, I could here subjoyn in confirmation of what I have been saying, to shew, that the Disposition of the Organ is of great Importance in the Dijudications we make of Colours, were it not that these strange Stories belonging more properly to another Discourse, I had rather, (contenting my self to have given you an Intimation of them here) that you should meet with them fully deliver'd there.
CHAP. III.
But, Pyrophilus, I would not by all that I have hitherto discours'd, be thought to have forgotten the Distinction
(of Colour) that I mentioned to you about the beginning of the third Section of the former Chapter; and therefore, after all I have said of Colour, as it is modifi'd Light, and immediately affects the Sensory, I shall now re-mind you, that I did not deny, but that Colour might in some sense be consider'd as a Quality residing in the body that is said to be Colour'd, and indeed the greatest part of the following Experiments referr to Colour principally under that Notion, for there is in the bodyes we call Colour'd, and chiefly in their Superficial parts, a certain disposition, whereby they do so trouble the Light that comes from them to our Eye, as that it there makes that distinct Impression, upon whose Account we say, that the Seen body is either White or Black, or Red or Yellow, or of any one determinate Colour. But because we shall (God permiting) by the Experiments that are to 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.