An idea of an artificial arrangement of fossils, according to unalterable characters, and superadded qualities : also of a natural method, according to their ascent towards their greatest perfection / By Sir John Hill.

Date:
1774
Catalogue details

Licence: Public Domain Mark

Credit: An idea of an artificial arrangement of fossils, according to unalterable characters, and superadded qualities : also of a natural method, according to their ascent towards their greatest perfection / By Sir John Hill. Source: Wellcome Collection.

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    [ *3 ] ftone; diffolving Part of its purer Chalk as ft goes 7* Water thus faturated with the Principles of Sulphur, and with Chalk, keeps on its gra¬ dual Courfe horizontally thro' the fame Lime Rock, till it meets a Fiffure; 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 flowly. 8. Slow Evaporation, and perfect Reft, are the Requifites of,Cryftalization. The Sulphur and pure Chalk thus united, form one folid Body; which cryftalizing gradually, appears in regular rhomboidal Particles : and is the Sub- ftance we call Spar •f*. * Limeftone is only coloured, hardened Chalk; and Marble is the fame. Marble is a purer Limeftone, and Limeftone a coarfer Marble. f Spar fuppofed to be one Thing, is therefore a mixed Body, and fo are the pureft Salts. We can make a Sub- ftance of the Nature of Spar, by cryftalizing the Lixivium of Lime and Sulphur. NATIVE i *
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