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SECT. II.
Of the Stone from which the Swedish Acid
is obtained,
THE Stone is of a peculiar Genus, differing both from Cryſtal and Spar; and demands a diſtinct Place and Name; as well from its natural Character, as for its artificial Products: It has been called Fluor, Spatum vitreſcens, and Fluſs. It is heavy, unctuous, ſoft, ſemi-tranſparent, and gloſſy: It breaks in a rudely plated Form; not rhombic.
We find it in large Maſſes; or Cluſters of ſmaller Lumps; in ſome Degree reſembling Spar, and of the like gloſſy Surface; but without the peculiar Form, or real Characters of that Stone.
A Knife will ſcratch it: It does not readily ferment with Acids, nor will it ſtrike Fire with Steel: It neither burns to Glaſs, nor Lime; but expoſed to the Action of a violent Fire, it ſplits into thin, irregular, flaky Fragments, and by Degrees crumbles into a Kind of Powder, over which the Fire has no farther Power. The Fragments do not this Way burn to Lime, nor can a calcareous Subſtance be any way extracted from them: But tho' no Fire will vitrify it alone, yet mixed with a calcareous Earth we ſee it pe culiruns freely into a Glaſs. And that it is of a
peculiar
