FRIEDRICH HEINRICH ALEXANDER, BARON VON HUMBOLDT, one of the greatest of naturalists, and who has contributed more than any man of modern times to the progress of several departments of physical science, was born at Berlin, September 14th, 1769. He studied at the universities of Frankfort on-the-Oder, Berlin, and Gottinger. His love of natural history was very strongly manifested at this period; and during his residence at Gottingen (1789-1790) he made visits of scientific exploration to the Harz and the banks of the Rhine, the fruit of which was his first publication, "On the Basalts of the Rhine." In the spring and summer of 1790, he accompanied George Forster in a tour through Belgium, Holland, England, and France. He was afterwards appointed to an office in the mining department, and spent some years in this capacity, chiefly at Fichtelgebirge, in upper Franconia. The desire of visiting tropical countries, however, led him to resign his office, and devote himself entirely to the study of nature. He sailed from Corunna, along with Bonpland, on the 5th of June, 1799. On the 16th of July they arrived at Cumana, an extent ot territory in Venezuela, Ecuador, and Peru, whence they sailed for Mexico, which they crossed from west to east. On the 17th of March, 1804, Humboldt sailed from Vera Cruz for Havana, where he spent two months. From Havana, he proceeded by sea to Philadelphia, and thence to Bordeaux, where he arrived after a course of travels unparalleled for variety and importance of scientific results, not only in the different departments of natural history, but also in geography, statistics and ethnography. Humboldt resided in Paris till March, 1805, occupied in the arrangement of his collections and manuscripts, and jointly with Gay-Lussac, in experiments on the chemical constitution of the atmosphere. Having visited Italy and returned to Berlin, he accompanied Prince Wilhelm of Prussia, in 1807, on a political mission to France, and obtained leave of the government of his own country to remain there, for the publication of his travels, for which the disturbed state of Germany at that time did not allow proper opportunity. He continued to reside in Paris till 1827. In 1807-1817, his great work appeared in twenty-nine volumes.
In 1829, Humboldt again became a traveller, the Emperor Nicholas then sending out a well appointed expedition to the north of Asia, to explore the Ural and Altai mountains, the Chinese Dsonga-rei, and the Caspian Sea. Its principal results were the scientific examination of the beds which produce gold and platina, the discovery of diamonds in an extra-tropical region, the astronomical determination of positions, magnetic observations, and geological and botanical collections. The whole journey occupied nine months, and extended to two thousand three hundred miles. Humboldt spent the latter years of his long life at Berlin, where he occupied a high position at the German court. His last great work, Cosmos, has been unanimously recognized as one of the greatest scientific works ever published, exhibiting in most lucid arrangement many of the principal facts of the physical sciences and their relations to each other. It has been translated into all the languages in which a book of science is required. Humboldt died May 6th, 1859. It is difficult to estimate the amount of Humboldt's contributions to science. The geography of Spanish America was most imperfectly known previous to his travels there, during which he asrtronomically determined more than 700 positions, and he bestowed much labor on the preparation of the maps in which his discoveries were exhibited. His barometrical observations were likewise very numerous, as well as his observations on all points connected with meteorology. To him we are indebted for the most important generalizations concerning magnetism, and also climate, some results of which are exhibited in the isothermal and other lines which are drawn on our maps.