FRIEDRICH MOHS (1773-1839), German mineralogist, was born at Gernrode in the Harz Mountains, on the 29th of January 1773. He was educated at Halle, and at the mining academy at Freiburg. He spent much time in Austria in studying mineralogy and mining, and became professor of mineralogy at Gratz in 1812. On the death of Werner in 1817, he was appointed to the chair of mineralogy in the mining academy of Freiburg, and in 1826 he became professor of mineralogy and superintendent of the Imperial Cabinet at Vienna. His great work was the Gruudriss der Mineralogie (Eng. trans. Treatise on Mineralogy, by Wilhelm Haidinger, 1825). He died at Agardo, near Belluno, Italy, on the 29th of September, 1839.