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ſtone; diſſolving Part of its purer Chalk as it goes^[1].

7. Water thus ſaturated with the Principles of Sulphur, and with Chalk, keeps on its gradual Courſe horizontally thro' the ſame Lime Rock, till it meets a Fiſſure; a perpendicular Crack, or Opening; dividing one Part of the Rock from another. Here it ouzes forth: and meeting with a lighter Air, hangs; and evaporates ſlowly.

8. Slow Evaporation, and perfect Reſt, are the Requiſites of Cryſtalization. The Sulphur and pure Chalk thus united, form one ſolid Body; which cryſtalizing gradually, appears in regular rhomboidal Particles: and is the Subſtance we call Spar^[2].

↑ Limeſtone is only coloured, hardened Chalk; and Marble is the ſame. Marble is a purer Limeſtone, and Limeſtone a coarſer Marble.
↑ Spar ſuppoſed to be one Thing, is therefore a mixed Body, and ſo are the pureſt Salts. We can make a Subſtance of the Nature of Spar, by cryſtalizing the Lixivium of Lime and Sulphur.

NATIVE

[1] Limeſtone is only coloured, hardened Chalk; and Marble is the ſame. Marble is a purer Limeſtone, and Limeſtone a coarſer Marble.

[2] Spar ſuppoſed to be one Thing, is therefore a mixed Body, and ſo are the pureſt Salts. We can make a Subſtance of the Nature of Spar, by cryſtalizing the Lixivium of Lime and Sulphur.

[1]

[2]