Page:Theophrastus - History of Stones - Hill (1774).djvu/281

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the Matter appears to be of extreme Strength, and fitted for enduring a long Time: After this they beat the Stones to Powder like Lime, to make them fit for Uſe.

CXX. From all this it ſeems evident, that the Properties and Nature of this Matter, are in a great Degree owing to the Fire^[1].

reſembling the others when they have paſſed the Fire.

↑ The Obſervation with which the Author concludes this Work is unqueſtionably moſt juſt. We are well acquainted with the many Changes which the Particles of Fire, inſinuating themſelves into Bodies, are able to make: Of which, their changing the Talcs and Alabaſters into Gypſum, and the Lime-ſtones of various Kinds into Lime, are not the leaſt worthy our Obſervation, though, from their being common, and every Day before our Eyes, they are but little regarded. What the Nature of that Change is; and that the Expulſion of the fixed Air from the Stones is the great Cauſe, we have now learned with Certainty from the ingenious and excellent Dr. Prieſtly.

[2] The Obſervation with which the Author concludes this Work is unqueſtionably moſt juſt. We are well acquainted with the many Changes which the Particles of Fire, inſinuating themſelves into Bodies, are able to make: Of which, their changing the Talcs and Alabaſters into Gypſum, and the Lime-ſtones of various Kinds into Lime, are not the leaſt worthy our Obſervation, though, from their being common, and every Day before our Eyes, they are but little regarded. What the Nature of that Change is; and that the Expulſion of the fixed Air from the Stones is the great Cauſe, we have now learned with Certainty from the ingenious and excellent Dr. Prieſtly.

[1]