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caused by Reffection from a Mixture os White and Black, or os diverflyColoured Corpuscles. But when such Imperfectly Mixt Light is by a secondReflection from the Paper more evenly and uniformly blended, it becomesmore pleafint, and exhiWts a faint or stiadowed Whitenesi. And that suchlittle Irregu laride* as thefe may caule diese differences, is not improbable, iswe consider, how much Variety may be caused in Sounds os the fame Tone,by irregulär and imeven Jarrtngs. And besides, thele differences are (o little,tfr.it I have sometimes doubted, whethcr they be any at all, when 1 have con-fldered, that a Black and White Body being placed together, the one in astrong Light, and the other in a very faint Light, so proportioned that theymight appear equally Luminous, it has been difficilst to distinguilh theni,when viewed at diftance, unlels when the. Black ieemed more Blueiffi • andthe White Body in a Light still fainter, bath,, in comparHon of the BlackBody; it solf appcared Black

This leads mc to another way of Compounding Wh steil eis; which is,that, is sour or five Bodies of the more eminent Colours, or a Paper pain-ted all over, in leveral parts of it wirh thole leveral Colours in adue Propor-tion, be placed in.the seid Beam of Light, the Light Reflected from thoseColours to another White Paper, hcld at a convenient diftance, {hall makethat Paper-appear White. If it be lieid too near the Colours, its Parts willfeem of j thole Colours that are ncarest them ; but by removing it further,that all its parts may be equally illümmated by all the Colours, they will bempre^and more dilute d, until they become perfectly White. And you mayfürthec obferve, that if any of the Colours be intercepted, the Paper will nolonger appear White, but ofthe other Colours which are not intercepted. Nowthat this Whitenels is a Mixture of rhe scverally Coloured Rays, falling con-Ldxdly on the Paper, I see no reason to doubt of; beeuule, if the Light bc-oapie Uniform and Similar betöre it seil confuscdly on the Paper, it must muchmore be Uniform, when at a greater diftance it falls on the Spectator’s Eye,and so the Rays, which come ftom feveral Colours, would in no Qualitiesdiffer from one another; but all of them exhibite die lameColour to the Spe-ctator, .contrary towhat he sees.

Not much unlike this Instance it is, that, if a Poliftid piece of JVletal beso placed, that the Colours appear in it asina Looking-glals, and then theMetal be made rough, that-by a confuled Reflection thole apparent Coloursaaaybe blended together, they shall dilappear, and by their Mixture caule the'Metal to look White.

Butfüriber to enforce this Experiment; If insteadof the Paper, any WhiteErpth consisting of Imall Bubbles, be illuminated by Reflexion ftom the afore-laid Colours, it {hall to the naked eye feem White, and yet through a gyodMictosoope the leVeral Colours will appear diltinct on die Bubbles, as ifleenby Reflexion from so many SphericaJ Surfaces. With my naked Eye, beingv«ry near, 1 hav£ also diseemedHhe feveral Colours on each Bubble j andyet at a greater diftance, where I'could not distinguiftr them apart, the Frothfraith appeared entirely White. And*at the ßme diftance, wheml looktin-tcotly, 1 hay* seen the. Cojlomi distinctly- oncach Babblej and yetby straining/ ray