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146 each of thee elementary Rays has inherently in it elf that which forms its Colour to the Eye, take a mall Piece of yellow Wood for Intance, and et it in the Ray of a red Colour, this Wood will intantly be ting'd red; but et it in the Ray of a green Colour, it aumes a green Colour, and o of all the ret. what Caue therefore do Colours arie in Nature? 'Tis nothing but the Dipoition of Bodies to reflect the Rays of a certain Order, and to aborb all the ret.

then is this ecret Dipoition? Sir Iaac Newton demontrates, that 'tis nothing more than the Denity of the mall contituent Particles of which a Body is compos'd. And how is this Reflexion perform'd? 'Twas uppos'd to arie from the Rebounding of the Rays, in the ame Manner as a Ball on the Surface of a olid Body; but this is a Mitake, for Sir Iaac taught the atonih'd Philoophers, that Bodies are opake for no other Reaon, but becaue their Pores are large; that Light reflects on