a. (UN-1 7.)

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1757.  trans. Henckel’s Pyritol. (title-p.), Its Iron, Copper, Unmetallic Earth, Sulphur [etc.].

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1796.  Kirwan, Elem. Min. (ed. 2), I. 487. Metallic substances … held in solution by any unmetallic acid.

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1841.  Brande, Man. Chem., 210. Heat is thrown off much more quickly from the unmetallic than from the metallic surface.

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1864.  Bowen, Logic, vi. 154. All infusible things are unmetallic.

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