LEOPOLD VON, an eminent German geologist and geographer, was born at Stolpe in Uckermark, April 25, 1774. In 1790 he studied at the mining school of Freiberg under the celebrated Werner. One of his fellow students at this school was the illustrious Alexander Von Humboldt. At the age of twenty-three he published his Attempt at a Mineralogical Description of Landech, and another Attempt at a Geognostic Description of Silesia. He was at this time a zealous upholder of the Neptunian theory of his illustrious master. In 1797 he met his old school-fellow Von Humboldt at Salzburg, and with him explored the geological formations of Styria and the adjoining Alps. In the spring of the following year, Von Buch extended his excursions into Italy, where his faith in the Neptunian theory was for the first time shaken. In his previous works he had advocated the aqueous origin of basaltic and other formations; he was now not less clearly convinced that these owed their existence to volcanic action. In 1799 he paid his first visit to Vesuvius, which he did not again see till 1805, when he was accompanied by Humboldt and Gay-Lussac. They had the good fortune to witness a remarkable eruption, which supplied Buch with data for refuting many erroneous ideas then entertained regarding the activity of volcanoes. Three years before, he had explored the south of France, and directed special attention to the extinct volcanoes of Auvergne. The aspect of the Puy de Dome, with its cone of trachyte and its strata of basaltic lava, induced him to abandon as untenable the doctrines of his master on the formation of these rocks. The scientific results of his investigations he embodied in his Geognostical Observations during Travels through Germany and Italy, Berlin, 1802-9, 2 vols. 8vo. From the south of Europe Von Buch now repaired to the north, and spent two years among the Scandinavian islands, making many important observations on the geography of plants, on climatology, and on geology. He also established the fact that the whole of Sweden is slowly but continuously rising above the level of the sea from Fredericksball to Abo. The details of these discoveries are given in his Travels through Norway and Lapland. Berlin, 1810. In 1815, he visited the Canary Islands in company with Christian Smith, the Norwegian botanist. His observations here convinced him that these and the other islands of the ocean owed their existence to volcanic action of the most intense kind, and that the groups of islands in the South Sea are the remains of a pre-existing continent. The physical description of the Canary islands was published at Berlin in 1825. After leaving the Canaries, Von Buch proceeded to visit the Hebrides and the coast of Scotland and Ireland. His geological excursions even into countries already repeatedly visited were continued without interruption till his 78th year. Eight months before his death, he visited the mountains of Auvergne; and on returning home he read a paper on the Jurassic Formation before the Academy of Berlin. The manner of Von Buch's life was singularly favourable to scientific pursuits. He inherited from his father a fortune more than sufficient for all his wants. He was never married, and was completely unembarrassed by family ties. His excursions he always undertook on foot, with a staff in his hand, and the large pockets of his overcoat filled with papers and geological instruments. Under this guise, the passer-by would not easily have recognised the man whom Humboldt has pronounced the greatest geologist of our era. He died at Berlin on the 4th of March 1853.

In addition to the works already mentioned, Von Buch published others, of which we may specify the magnificent Geological Map of Germany, in 42 sheets. Berlin, 1832.