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BASALT. 83 times melted, and blown into glass bottles, which have a dark green colour, and are said to be harder and more durable than those made of common green glass. Al though it is harder, more brittle, and less obedient to the chisel, and its colours not so pleasing and durable as those of marble, yet the ancients, who were acquainted with its greater indestructibility, executed several fine works in it. Fliny describes several fine pieces of sculpture said to have been executed in this stone; and the famous statue of Minerva, at Thebes, is described by travellers as being of basalt. Antiques of basalt are always in a much better state of preservation than those of marble. Even those dug out of the earth, are never covered with that tufaceous crust we find investing those made of marble; they still retain the original polish, and the finest touches of the chisel are preserved unimpaired. Many of the antique basalts preserved in collections, are evidently greenstone, syenite, or hornblende-rock. Observations. E The popular name of this mineral in Scotland, is H huistone; but all whinstones are not basalt; for the name is applied to greenstone, clinkstone, wackc, trap- tulf, porphyry, grey-wacke, and other rocks. 2. Humboldt, Voigt, Faujas St Fond, and Hauy, maintain its volcanic origin ;—Werner, Mohs, Steffens, Klaproth, and Karsten, its neptunian origin;—Von Buchj Dolomieu, l)aubuisson, and others, its double origin, sometimes volcanic, sometimes neptunian ;—and Hutton, Elayfair, Hall, See. its plutonic formation. The theory its formation will be considered in the geognostic part fl f this work. « V * S. Wacke.