French Scientists Explore the Amazon River
The exploration of the Amazon River by French scientists in the 18th century was a significant scientific endeavor led by mathematician Charles-Marie de La Condamine. This expedition aimed to measure one degree of latitude at the equator, addressing longstanding navigational inaccuracies related to the Earth's shape. The French Academy of Sciences, motivated by the need for precise geodetic measurements, dispatched La Condamine and a team of ten scientists to Ecuador in May 1735. The expedition gained permission to work in Spanish territory due to the political ties between France and Spain.
Upon completing their measurements, La Condamine, alongside fellow scientist Pedro Vicente Maldonado, sought to enhance a Jesuit map of the Amazon River and its surroundings. This journey began in March 1741 and involved extensive scientific observation, during which La Condamine documented the river's dynamics, indigenous cultures, and tropical flora. His findings contributed to early understandings of plant life, particularly quinine and rubber, and highlighted the role of missionaries in early vaccination efforts against smallpox. La Condamine's work not only enriched geographical knowledge but also paved the way for the eventual adoption of the metric system in France.
French Scientists Explore the Amazon River
Date May, 1735-1743
La Condamine and his crew rafted the 3,000-mile-long Amazon River, producing the first scientific accounts of the river and region. In addition to charting the river, he discovered the value of rubber and observed the work of Jesuit missionaries with indigenous peoples.
Locale Ecuador; Brazil; French Guiana
Key Figures
Charles-Marie de La Condamine (1701-1774), French mathematician and scientistPedro Vicente Maldonado (1704-1748), Ecuadoran provincial official and scientist
Summary of Event
Although the fifteenth century saw considerable advancements in mapmaking, at the beginning of the eighteenth century maps continued to present navigational errors because of imprecision regarding the size of one degree of latitude. It was not certain whether Earth was a perfect sphere. The size of a degree of latitude would not be uniform over the globe if the sphere were not evenly curved. Moreover, Sir Isaac Newton argued that Earth was flattened at the poles and bulged at the equator. Therefore, the measure of one degree of latitude would have to be appropriately adjusted depending on one’s distance from the poles.
To address this important question for the natural sciences and world navigation, the French Academy of Sciences sent an expedition to Ecuador to measure one degree of latitude at the equator. A young, wealthy, and brilliant mathematician and specialist in the emerging field of geodesy, Charles-Marie de La Condamine, was a member of the expedition. He secured his participation through the support of the noted writer Voltaire, who helped La Condamine with a considerable subsidy.
In May of 1735, a group of ten scientists and technicians set out from France for South America. Through the Caribbean, Colombia, and Panama they journeyed with their supplies and scientific equipment. By the middle of the following year they had arrived in Quito, Ecuador, and began conducting measurements in the region. The academy had selected Ecuador as the base because other locations in the world were considered too hostile or inaccessible. Ecuador, however, was Spanish territory, part of the rich mining regions that economically supported its empire.
The French scientists received permission to work in Spanish territory because the two countries shared the same ruling dynasty, the Bourbons. The scientists were accompanied by Spanish military officials throughout the expedition. In Ecuador, La Condamine met Pedro Vicente Maldonado, a young provincial official and emerging scientist with whom he formed a lasting professional partnership.
The work of measurement was a monumental task. It involved the laying of long measuring chains through the mountains, calculating and checking distances through triangulation, and displaying measurements and findings in maps and tables. The work continued throughout the rest of the decade and was successful in verifying the bulge of Earth. However, it failed to be the first to present its findings to the French Academy. Another French expedition, which had worked toward the North Pole, reported its findings to the academy in 1739.
Because of crew deaths and marriages, international conflicts, and internal strife, the Ecuador expedition began to break up at the beginning of the following decade. However, because La Condamine had associated with the Jesuits in Quito, he was able to conceive of an expedition down the Amazon River. The Jesuits maintained Indian missions throughout the region. Because the river ran through territory that both Spain and Portugal claimed, both Spanish and Portuguese Jesuits were settled in the area. A Spanish Jesuit had made the first detailed map of the 3,000-mile-long river, indicating the tributaries, missions, and tribes to be found along its course. To verify and improve upon this map, La Condamine resolved to return to Europe, accompanied by Maldonado, by descending the Amazon, which travels in a northeasterly direction. Appreciating the value this task could have for their missionary work, the Jesuits helped the explorers acquire dugout canoes, indigenous oarsmen, and guides. The missions would serve as way stations for the expedition.
La Condamine began the journey from Ecuador in March of 1741, but he and Maldonado did not arrive at the mouth of the Amazon, in the city of Belem do Pará, until September. The two were considered no threat to Portuguese officials, since the gold and diamond mines of Brazil lay far southeast of the Amazon.
About a year after departing, in 1743, and over the course of six months, La Condamine made the first systematic and scientific observations of the river. He corrected aspects of the Jesuit map regarding the rise, flow, and tides of the river and its tributaries. He noted the varied customs and languages of indigenous groups. Ever fascinated by the plant life of the tropics, he continued the observations he began in Ecuador on quinine and the intriguing phenomenon of rubber. He believed that a canal of sorts (the Casiquiare River) connected the Amazon with the Orinoco River in Venezuela. From Brazil, La Condamine traveled to Cayenne, a French territory in Guyana, west of the Amazon. He arrived in France in 1745, after a ten-year absence.
Significance
In the same year as his return, Charles-Marie de La Condamine published Relation abrégée d’un voyage fait dans l’intérieur de l’Amérique Méridionale (1745; A Succinct Abridgment of a Voyage Made Within the Inland Parts of South-America, 1747), a work in journal form about his adventures and discoveries in Brazil and Guyana. In 1751 he published a historical and technical account of his Ecuador expedition, Journal du voyage fait par ordre du roi, à l’équateur (journal on the voyage to the equator made by order of the king).
Of great importance for medicine and public health were his narratives relating the work of missionaries in the lower Amazon who had used an early form of inoculation since about the late 1720’s to protect the indigenous population from smallpox. La Condamine would become an ardent supporter of vaccination in Europe. He also became a champion of both the utility and novelty of rubber.
La Condamine was a key patron of the campaign to standardize the system of measurement. Complicating his work in Ecuador was the multiplicity of measuring systems used by Europeans. His efforts to standardize measurement would result in the metric system, officially adopted for the first time by any country in 1795, by France.
Bibliography
Cohen, J. M. Journeys Down the Amazon: Being the Extraordinary Adventures and Achievements of the Early Explorers. London: C. Knight, 1975. Narrates the history of Amazon expeditions and explorers for the century prior to the time of La Condamine.
Guadalupi, Gianni, and Anthony Shugaar. Latitude Zero: Tales of the Equator. New York: Carroll & Graf, 2001. Relates the equatorial experiences of La Condamine and places them in the context of expeditions by others in South America, Africa, Asia, and Oceania.
Kafker, Frank A. “A List of Contributors to Diderot’s Encyclopedia.” French Historical Studies 3, no. 1(Spring, 1963): 106-122. La Condamine is listed along with all other contributors the encyclopedia published between 1751 and 1772 by Denis Diderot. This article helpfully indicates the volume and page numbers of the articles.
Livingstone, David N., and Charles W. J. Withers. Geography and Enlightenment. Chicago: University of Chicago Press, 1999. A collection of articles that reviews the study of Earth and the development of the discipline of geography during the eighteenth century.
Smith, Anthony. Explorers of the Amazon. London: Viking, 1990. Includes the chapter “Charles-Marie de La Condamine: Equatorial Scientist,” which provides a historical context for the voyage in relation to other European explorers from the mid-sixteenth century to the early twentieth century.
Von Hagen, Victor Wolfgang. South America Called Them: Explorations of the Great Naturalists, La Condamine, Humboldt, Darwin, Spruce. 3d ed. Boston: Little, Brown, 1955. Nine chapters examine the life of La Condamine, his experiences in South America from 1735 to 1743, and the significance of his work and findings.