Reitter, in " Platypsylla castoris Rits. als Vertreter einer neuer europaischen
— from Scientific American Supplement, No. 648, June 2, 1888. by Various
Thousands of feet of carbon rods are volatilized every night in the arc lamps of our cities, but the trouble is that this carbon vapor so formed, when cooled, or condensed, is not converted into the exceedingly hard, clear, crystalline diamond, but into the soft, dull black graphite or plumbago.
— from The Wonder Book of Volcanoes and Earthquakes by Edwin J. (Edwin James) Houston
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