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 away before they get it. In Phœnicia and The Syrian, or third kind of Gypum, this Author here oberves, was made by burning certain Stones, which he afterwards very well decribes, and which we may fee from his Account were of the very Kind with thoe we now principally ue for that Purpoe, and call Parget, or Plaiter-tone, different kinds of which are dug in Derbyhire and Yorkhire in England, and the Pits of Montmartre in France. There are many other Kinds in different Parts, both of France and England, very little different from thee and from each other; but in general all of them very well anwer the Decription Theophratus gives of the Stones from which what I have called the Syrian Gypum of the Antients was made.

It is to be oberved that we, as well as the Antients, burn many very different Stones into our Gypum, or Plaiter of Paris, as it is commonly called; ome of which are of the Nature of the foliaceous, others of the fibrous Talcs; others compoed of Matter eeming the ame with that of the Talcs, but amaed together in a different Form, being neither fibrous nor foliaceous, but eemingly in a coare Powder, or arenaceous Particles of uncertain Figures, and held together in the ame manner as the Grit of the Stone of Strata: And finally, others truly and legitimately of the Alabater kind; in many of thee, Particles of genuine parry Matter alo dicover themelves; and in everal, the Maes are wholly urrounded with, and in many Places their very Subtance is penetrated by a reddih earthy Matter: Thee require different Degrees of burning, according to their different Texture, to bring them to the State proper for Ue: But in mot of them it is done in a very little Time, and by a very light Calcination, in comparifon to that required for equally altering mot other Subtances. The reddih Kinds burn to a Gypum equally white with that made from the whitet. The Gypum of Montmartre in France, Syria alo they have a Gypum, which they make by burning certain Stones. They have a Gypum in Thuria too, in great Plenty; as alo about Tymphæa, and in the Country of the