Alexander von Humboldt and the Plants of South America

Alexander von Humboldt's exploration of South America, accompanied by the French botanist Aime Bonpland (1773–1858), did much to establish biogeography as a distinct scientific discipline, but Humboldt was much more than a geographer. In his most famous work, Kosmos, published in five volumes between 1845 and 1862, he wrote that “I always wanted . . . to understand nature as a whole . . . the separate branches of natural knowledge have a real and intimate connection.” He was an Earth scientist who founded a school of mining and invented a safety lamp for miners. He studied volcanoes, measured the Earth's magnetic field, and discovered the Peru Current off the Pacific coast of South America—it is sometimes called the Humboldt Current. He was a professional diplomat, a fervent opponent of slavery, and a supporter of self-determination for the citizens of European colonies. The illustration at left is from a portrait painted in 1806, two years after his return from South America, when he was 37 years old.

In June 1802 Humboldt and Bonpland, accompanied by Carlos Montufar (1780–1816), climbed Mount Chimborazo in Ecuador. This volcano, 20,569 feet (6,269 m) high, was thought at the time to be the world's highest mountain, and the group reached a height of 18,893 feet (5,762 m) before mountain sickness defeated them. Humboldt recognized that it was lack of oxygen that caused the illness, but there was nothing they could do but descend. Nevertheless, when news of their climb reached Europe it made them into celebrities.

Alexander von Humboldt (1769–1859) was a Prussian naturalist and geographer who explored Central and South America. This portrait, painted in 1806, two years after his return, shows him studying a plant specimen. (Bildarchiv Preussischer Kulturbesitz/Art Resource)

They did not simply climb the mountain, however. As they went they recorded the plants growing on the mountainside and their locations. Later Humboldt drew a cross section of the mountain, with the names of the plants at their correct altitudes written onto the drawing. He added two tables, one on each side of the main drawing, in which he recorded the temperature, barometric pressure, and other climatic details at each elevation.

That drawing clearly demonstrated his belief in the interconnectedness of natural phenomena. During their exploration of what was then Spanish America, Humboldt and Bonpland collected 5,800 species of plants, of which 3,600 were unknown to science until that time. They—but mainly Bonpland—identified and classified most of them before leaving the United States.

Humboldt's full name was Friedrich Wilhelm Heinrich Alexander, baron (Freiherr) von Humboldt, and he was born in Berlin, then the capital of Prussia, on September 14, 1769. He was taught by tutors before entering the University of Frankfurt-an-der-Oder in 1789 to study economics, followed by a year at the University of Gottingen, where he developed the interest in natural history he had shown since he was a young child. In 1791 Humboldt enrolled at the Freiberg School of Mining (now the Technische Universitat Bergakademie Freiberg). He left in 1792 without taking a degree and was appointed inspector of mines.

Following the death of his mother in 1796, Humboldt inherited a considerable sum of money. In 1797 he resigned from the Prussian department of mines and went to Paris, where he met and became friendly with the French botanist Aime Bonpland. The two friends traveled to Madrid, where the Spanish prime minister obtained official permission for them to visit Spain's American colonies. They sailed from Marseille and arrived at Cumana, New Andalusia (now Venezuela), on July 16, 1799. By the end of their exploration in 1804, Humboldt and Bonpland had traveled more than 6,000 miles (9,650 km) on foot, horseback, and by canoe. The following map shows the route they followed.

Humboldt lived in Paris from 1804 until 1827, writing his account of the travels. His Essay on the Geography of Plants appeared in 1805 and became volume 5 of his 23-volume Personal Narrative of Travels to the Equinoctial Regions of the New Continent, coauthored with Bonpland, the final volume of which was published in 1824. He spent his final years working on Kosmos, his greatest masterpiece, which developed from a series of lectures he delivered in Berlin in 1827–28. In it he aimed to bring together all of the sciences in a comprehensive portrait of the Earth. The first two volumes were published between 1845 and 1847, volumes 3 and 4 between 1850 and 1858, and as much of volume 5 as he was able to complete appeared in 1862 after his death. Humboldt suffered a minor stroke on February 24, 1857, from which he recovered, but his strength weakened during the winter of 1858–59, and he died peacefully on May 6, 1859. He was given a state funeral.

The route Alexander von Humboldt and Aime Bonpland followed through Central and South America between 1799 and 1804

Aime-Jacques-Alexandre Goujaud was born in La Rochelle, France, on August 28, 1773. He later changed his name to Bonpland. He studied medicine in Paris from 1791 to 1794, served as a surgeon in the French army until 1795, and then resumed his medical studies. On his return to France in 1804, Bonpland was awarded an official pension and made director of the empress Josephine's private botanical garden at Malmaison, her country house about seven miles (11 km) from Paris, where he spent much of his time arranging his botanical collections and writing. In 1808 Josephine appointed him her official botanist. In 1813 Bonpland published Description des Plantes Rares Cultivee a Malmaison et a Navarre (Description of the rare plants cultivated at Malmaison and Navarre), a book describing the contents of Josephine's garden. Josephine died in 1814, and in 1816 Bonpland returned to South America to take up a post as professor of natural sciences in Buenos Aires, Argentina, where he also practiced medicine. In 1817 he was made a corresponding member of the French Academie des Sciences. In 1820 he left Buenos Aires to establish and run a plantation near the Parana River, but he offended the dictator of Paraguay, who had him detained until 1829. After his release, Bonpland started other plantations in Brazil and Uruguay, which he managed from 1831 until his death. In 1854 Bonpland was decorated by King Friedrich Wilhelm III of Prussia and in 1856 he received an honorary degree from the University of Greifswald, in Germany. Bonpland died on May 11, 1858, at Restauracion, Argentina.