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Rh ; that Bodies are not tranparent when they have large Pores; and that a Man hould arie, who would demontrate all thee Paradoxes, and anatomize a ingle Ray of Light with more Dexterity than the ablet Artit diects a human Body. This Man is come. Sir Iaac Newton has demontrated to the Eye, by the bare Aitance of the Prim, that Light is a Compoition of colour'd Rays, which, being united, form white Colour. A ingle Ray is by him divided into even, which all fall upon a Piece of Linen, or a Sheet of white Paper, in their Order one above the other, and at unequal Ditances. The firt is Red, the econd Orange, the third Yellow, the fourth Green, the fifth Blue, the ixth Indigo, the eventh a Violet Purple. Each of thee Rays tranmitted afterwards by an hundred other Prims, will never change the Colour it bears; in like Manner as Gold, when completely purg'd from its Dros, will never change afterwards in the Crucible. As a uperabundant Proof that Rh