Russian geologist, born at Laugut-Duckershof, near Dorpat, on the 29th of September (O.S.) 1803. He received an engineering training and became major-general in the corps of Mining Engineers. In 1837 he was appointed professor of geology in the mining institute at St. Petersburg. He was author of numerous memoirs on the geology of Russia, especially on the coal and other mineral deposits of the country; and he wrote also some explanations to accompany separate sheets of the geological map of Russia. His geological work was continued to an advanced age, one of the later publications being Studien über die Wanderblöcke und die Diluvialgebilde Russlands (1869 and 1882). Most of his memoirs were published by the Imperial Academy of Sciences at St. Petersburg. He died at St. Petersburg on the 3rd of February (O.S.) 1885.