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Resractions, are made to Diverge towards severa 1 parts of the Retina , andthere expreß the Images of things Coloured, as in the former case they didthe Sun’s Image upon a Wall. Andby this Inequalityof Resractions, theybecome not only Coloured, but allb very Confu/cd and Indistinct.

10. Why the Colours of the Rainbow appear in falling drops of Rain, isalso from hence evident. For thole drops which Refract the Rays, difpoled -to appear Purple; in greatest quantity to the Spectator’s Eye, Refract theRays cf othcr forts Ib much leis, as to make them pass beside it; and luchare the drops on the inside of the Primary Bow, and on the outside of the Se-cundary or Exterior one. So thole drops, which Refract in greatest'plenty theRays, apt to appear Red, towardthe Spectator’s Eye, Refract thole ofotherlortsIb much more, as to make them pafs beside it; and luch are the drops on theExterior part of the Primary, and. Interieur part of the Secondary Bow.

11. The odd Phaenomena of an Infusion of Lignum Nephriticum, Leas-Gold, fragmenta of Coloured-Glals, and tome other tranlparendy ColouredBodies, appearing in one Position of one Colour, and of another in anotliev,,are on thele grounds no longer RiJdles. For thole are Substances apt to Re-stect one fort of Light, and. traniinit another; as may be leen In adarkRoom,by Uluminating them with similar or uncompounded I.ight. For then theyappear of that- Colour only, with which they are iiluminated, but yet in one -Position more Vivid and Luminous than in another, accordingly as they aredilpoled more or leß to Rcflect or Traniinit the incident Colour.

ii. From hence also is manifest the reatbn of an unexpected Experiment',which Mr. Isook, somewhcre ia WisMicrography, relates to have made with twoWedg-like Transparent Veflels, filled the one with a Red, the other with' a.Blue Liquor : namely, that though they were leverally Transparent enough,-yet both together became Opake ; For if one transinitted only Red, and the'other only Blue, no Rays could pals thro’ both.

iz. I might add more Instances of this Nature, but I Ihall conclude, with-.:this General one, That the Colours ot all Natural Bodies have no other- Ori-gin than this,. that they are varioully qualificd; to Reflcct one lort of Lighuin greater plenty than another. And- this I have Expci imented in a darkRoom, by illuminating thole Bodies with uncompounded Light of divers Co--lours. For by that means any Body may be made to appear of any Colour.They have there no-appropriate Colour, but everappear oi the Colour of theLight cast upon them, hüt yet with this difference, .that they arc most brisk.and vivid in the Light of their own Day-light Colour. Miniumappeareth.there.of any Colour indifferently, with which it is illustratcd, but yet most Lumi-,nousin Red; and so Bife appeareth indifferently of any Colour; with which-it Villustrated, but yet most Luminous in Blue. And therefore Minium. Reflecteth.:Rays of any Colour, but most copioufly thole, endowcd with Red ; and conte-.quently when illustratcd with Day-light; that is, with alhsorts of Rays promiEcuoufly blcndcd, thole qualihed withRed (hall abound most in the Reflected Lighr^,,and by their prevalence caute it to appear. of that Colour. And for the same-Rea-son Bile, Reflecting Blue most-copioufly, flrall appear.Blue by the exce (s of thole.Raysinits Reflected Light.; and the llkeof other Bodies. Andthar this is the.in-

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