6. I know indeed that divers Learned Men think, that Snow ſo ſtrongly Affects our Eye, not by a Borrow'd, but a Native Light; But I venture to give it as a Proof, that White Bodies reflect more Light than Others, becauſe having once purpoſely plac'd a parcel of Snow in a Room carefully Darkned, that no Celeſtial Light might come to fall upon it; neither I, nor an ingenous Perſon, (Skill'd in Opticks) whom I deſir'd for a Witneſs, could find, that it had any other Light than what it receiv'd. And however, 'tis uſual among thoſe that Travel in Dark Nights, that the Guides wear ſomething of White to be Diſcern'd by, there being ſcarce any Night ſo Dark, but that in the Free Air there remains ſome Light, though Broken and Debilitated perhaps by a thouſand Reflections from the Opacous Corpuſcles that Swim in the Air, and lend it to one another before it comes to arrive at the Eye.
7. Thirdly, And the better to ſhew that White Bodies reflect ſtore of Light, in comparſon of thoſe that are otherwiſe Colour'd, I did in the Darkn'd Room,
formerly mention'd, hold not far from the Hole, at which the Light was admitted, a Sheet only of White Paper, from whence caſting the Sun-beams upon a White Wall, whereunto it was Obverted, it manifeſtly appear'd both to Me, and to the Perſon I took for a Witneſs of the Experiment, that it Reflected a far greater Light, than any of the other Colours formerly mention'd, the Light ſo thrown upon one Wall notably Enlightning it, and by it a good part of the Room. And yet further to ſhow you, that White Bodies Reflect the Beams From them, and not Towards themſelves, Let me add, that Ordinary Burning-glaſſes, ſuch as are wont to be employ'd to light Tobacco, will not in a great while Burn, or ſo much as Diſcolour a Sheet of White Paper. Inſomuch that even when I was a Boy, and Lov'd to make Tryals with Burning-glaſſes, I could not but wonder at this Odd Phænomenon, which ſet me very Early upon Gueſſing at the Nature of Whiteneſs, eſpecially becauſe I took notice, that the Image of the Sun upon a White Paper was not ſo well Defin'd (the Light ſeeming too Diffus'd) as upon Black, and becauſe I try'd, that Blacking over the Paper with Ink, not only the Ink would be quickly Dry'd up, but the
Paper that I could not Burn before, would be quickly ſet on Fire. I have alſo try'd, that by expoſing my Hand with a Thin Black Glove over it to the Warm Sun, it was thereby very quickly and conſiderably more Heated, than if I took off the Glove, and held my Hand Naked, or put on it another Glove of Thin but White Leather. And having thus ſhewn you, Pyrophilus, that White Bodies reflect the moſt Light of any, let us now proceed, to conſider what is further to be taken notice of in them, in order to our preſent Enquiry.
8. And Fourthly, whereas among the Diſpoſitions we attributed to White Bodies, we alſo intimated this, That ſuch Bodies are apt, like Speculums, though but Imperfect ones, to Reflect the Light that falls on them Untroubled or Unſtain'd, we ſhall beſides other particulars to be met with in theſe Papers, offer you this in favour of the Conjecture; That in the Darkned Room ſeveral times mention'd in this Treatſe, we try'd that the Sun-beams being caſt from a Coloured Body upon a neighbouring White Wall, the Determinate Colour of the Body was from the Wall reflected to the Eye; whereas we could in divers caſes manifeſtly Alter the Colour arriving at the Eye, by Subſtituting
at a convenient Diſtance, a (conveniently) Colour'd (and Gloſſy) Body inſtead of the White Wall. As by throwing the Beams from a Yellow Body upon a Blew, there would be Exhibited a kind of Green, as in the Experiments about Colours is more fully Declar'd.
9. I know not whether I ſhould on this Occaſion take notice, that when, as when looking upon the Calm and Smooth Surface of a River betwixt my Eye and the Sun, it appear'd to be a natural Speculum, wherein that Part which Reflected to my Eye the Entire and defin'd Image of the Sun, and the Beams leſs remote from thoſe which exhibited That Image, appear'd indeed of a great and Whitiſh Brightneſs, but the reſt Comparatively Dark enough: if afterwards the Superficies chanc'd to be a little, but not much troubled, by a gentle Breath of Wind, and thereby reduc'd into a Multitude of Small and Smooth Speculums, the Surface of the River would ſuitably to the Doctrine lately deliver'd, at a Diſtance appear very much of Kin to White, though it would loſe that Brightneſs or Whiteneſs upon the Return of the Surface to Calmneſs and an Uniform Level. And I have ſometimes for Tryals ſake brought in by a Lenticular Glaſs, the Image of a River, Shin'd upon
by the Sun, into an Upper Room Darkn'd, and Diſtant about a Quarter of a Mile from the River, by which means the Numerous Declining Surfaces of the Water appear'd ſo Contracted, that upon the Body that receiv'd the Images, the whole River appear'd a very White Object at two or three paces diſtance. But if we drew Near it, this Whiteneſs appear'd to proceed from an Innumerable company of Lucid Reflections, from the ſeveral Gently wav'd Superficies of the Water, which look'd Near at hand like a Multitude of very Little, but Shining Scales of Fiſh, of which many did every moment Diſappear, and as many were by the Sun, Wind and River generated anew. But though this Obſervation ſeem'd Sufficiently to diſcover, how the Appearing Whiteneſs in that caſe was Produc'd, yet in ſome other caſes Water may have the Same, though not ſo Vivid a Colour upon other Accounts; for oftentimes it happens that the Smooth Surface of the Water does appear Bright or Whitiſh, by reaſon of the Reflection not immediatly of the Images of the Sun, but of the Brightneſs of the Sky; and in ſuch caſes a Convenient Wind may where it paſſes along make the Surface look Black, by cauſing many ſuch Furrows and Cavities, as may make the Inflected Superficies
of the Water reflect the Brightneſs of the Sky rather Inward than Outward. And again if the Wind increaſe into a Storm, the Water may appear White, eſpecially near the Shore and the Ship, namely becauſe the Rude Agitation Breaks it into Fome or Froth. So much do Whiteneſs and Blackneſs depend upon the Diſpoſition of the Superficial parts of a Body to Reflect the Beams of Light Inward or Outward. But that as White Bodies reflect the moſt Light of any, ſo there Superficial Particles are, in the Senſe newly Deliver'd, of a Specular Nature, I ſhall now further endeavour to ſhew both by the making of Specular bodies White, and the making of a White body Specular.
10. In the Fifth place then, I will inform You, that (not to repeat what Gaſſendus obſerves concerning Water) I have for Curioſity ſake Diſtill'd Quickſilver in a Cucurbit, fitted with a Capacious Glaſs-head, and obſerv'd that when the Operation was perform'd by the Degrees of Fire requiſite for my purpoſe, there would ſtick to the Inſide of the Alembick a multitude of Little round drops of Mercury. And as you know that Mercury is a Specular Body, ſo each of theſe Little drops was a ſmall round Looking-glaſs,