9. Sixthly, I remember, that Acquainting one Day a Virtuoso of Unsuspected Credit, that had Visited Hot Countries, with part of what I have here Deliver’d concerning Blackness, he Related to me by way of Confirmation of it, a very notable Experiment, which he had both others make, and Made himself in a Warm Climate, namely, that having carefully Black’d over Eggs, and Expos’d them to the Hot Sun, they were thereby in no very Long time well Roasted, to which Effect I conceive the Heat of the Climate must have Concurr’d with the Disposition of the Black Surface to Reflect the Sunbeams Inward, for I remember, that having made that among other Tryals in England, though in Summer-time, the Eggs I Expos’d, acquir’d indeed a considerable Degree of Heat, but yet not so Intense a One, as prov’d Sufficient to Roast them.
10. Seventhly, and Lastly, Our Conjectures at the Nature of Blackness may be somewhat Confirm’d by the (formerly mention’d) Observation of the Blind Dutch-man, that Discerns Colours with his Fingers; for he Says, that he Feels a greater Roughness upon the Surfaces of Black Bodies, than upon those of Red, or Yellow, or Green. And I remember, that the Diligent Bartholinus says,[9] that a Blind Earl of Mansfield could Distinguish White from Black only by the Touch, which would Sufficiently Argue a great Disparity in the Asperities, or other Superficial Textures of Bodies of those two Colours, if the Learn’d Relator had Affirm’d the Matter upon his own Knowledge.
[9] Hist. Anatom. Cent. 3. Hist. 44.
II. These, Pyrophilus, are the chief things that Occurr to me at present, about the Nature of Whiteness and Blackness, which it they have Rendred it so much as Probable, that in Most; or at least Many Cases, the Causes of these Qualities may be such as I have Adventur’d to Deliver, it is as much as I Pretend to; for till I have Opportunity to Examine the Matter by some further Tryals, I am not sure, but that in some White and Black Bodies, there may Concurr to the Colour some peculiar Texture or Disposition of the Body, whereby the Motion of the Small Corpuscles that make up the Incident Beams of Light, may be Differingly Modify’d, before they reach the Eye, especially in this, that White Bodies do not only Copiously Reflect those Incident Corpuscles Outwards, but Reflect them Briskly, and do not otherwise Alter them in the manner of their Motion. Nor shall I now stay to Enquire, whether some of those other ways, (as a Disposition to Alter the Velocity, the Rotation, or the Order and Manner of Appulse so the Eye of the Reflected Corpuscles that Compos’d the Incident Beams of Light) which we mention’d when we consider’d the Production of Colours in General, may not in some Cases be Applicable to those of White and Black Bodies: For I am yet so much a Seeker in this Matter, and so little Wedded to the Opinions I have propos’d, that what I am to add shall be but the Beginning of a Collection of Experiments and Observation towards the History of Whiteness and Blackness, without at present interposing my Explications of them, that so, I may assist your Enquires without much Fore-stalling or Biassing your Judgment.