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 And the Star does not diolve or effervece with Acids: In thee Things the two approach to the new Stone; but neither can be allowed the ame.

The green owes its Colour, motly, to Iron.

I am convinced that ome of this Stone contains that Metal; but not all; and that the Iron, where it is found, is no Eential Part of the Body; but a mere accidental Mixture: For I have Pieces from Sweden, which, tho' very green, do not become red in burning; and other green Pieces that acquire that Rednes, which appears after burning in all Foils that have Iron in them.

From thee palpable Qualities; and certain Characters; we may advance toward an Enquiry into what it is.

The Mineral Acid, every where preent in the Earth, (tho' never een unmixed, or in its pure, imple tate) when joined with Metals, we ee, forms the Vitriols; when united with Clay it makes the Alums; when mixed with any