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fore breaks into, both theſe Forms. It is unwillingly I diſſent in a few Particulars, from an Author with whom Reaſon and Obſervation command me to agree in a great many: But this is a Doctrine which ſtrikes at the Root of all accurate Knowledge in reſpect of this Body.
By this Account Spar would be two Things, not one: Its Atoms would have two Figures; and we ſhould loſe the great Diſtinction by which it is kept ſeparate from all other Bodies. I have examined this Point with all poſſible Attention; and find the pyramidal Figures of Spar, whether in greater or ſmaller Pieces, to be a ſecondary Form; compoſed always of Rhombs: But the rhombic Figure never to have any Form in its conſtituent Parts beſide its own. The Pyramids, great or ſmall, ſeparate into Rhombs; the Rhombs never into Pyramids. The true Way of dividing Spar is, by an Acid, carefully managed; for the Parts are always ſeparated, before they are diſſolved.
It is a ſingular and a juſt Obſervation of the ſame Author, that no pentagonal Spar has ever been found; tho' Angles in moſt other Numbers are frequent; but this is not to be attributed with him, to an imaginary Salt, Alcaline, and Muriatic; it reſts upon a much more ſolid Baſe: Which is, that the particular Figure of the Rhombs of Spar, admit the conſtructing any other angulated Form, only not pentagonal.
