Charles Marie de La Condamine
Charles Marie de La Condamine (28 January 1701 – 13 February 1774) was a French explorer, geographer, and mathematician. He spent ten years in present-day Ecuador measuring the length of a degree latitude at the equator and preparing the first map of the Amazon region based on astronomical observations.
Charles Marie de La Condamine was born in Paris as a son of well-to-do parents, Charles de La Condamine and Louise Marguerite Chourses. He studied at the Collège Louis-le-Grand where he was trained in humanities as well as in mathematics. After finishing his studies, he enlisted in the army and fought in the war against Spain (1719). After returning from the war, he became acquainted with scientific circles in Paris. On 12 December 1730 he became a member of the Académie des Sciences and was appointed Assistant Chemist at the Academy.
The next year (May 1731) he sailed with the Levant Company to Constantinople (now Istanbul), where he stayed five months. After returning to Paris, La Condamine submitted in November 1732 a paper to the Academy entitled Mathematical and Physical Observations made during a Visit of the Levant in 1731 and 1732.
Three years later he joined an expedition to present-day Ecuador which had the aim of testing a hypothesis of Isaac Newton. Newton had posited that the Earth is not a perfect sphere, but bulges around the equator and is flattened at the poles. Newton's opinion had raised a huge controversy among French scientists. Pierre Louis Maupertuis, Alexis Claude Clairaut, and Pierre Charles Le Monnier traveled to Lapland, where they were to measure the length of several degrees of latitude orthogonal to the arctic circle, while Louis Godin, Pierre Bouguer, and La Condamine were sent to South America to perform similar measurements around the equator.
On 16 May 1735, La Condamine sailed from La Rochelle accompanied by Godin, Bouguer, and a botanist, Joseph de Jussieu. After stopovers in Martinique, Santo Domingo, and Cartagena (Colombia), they came to Panama where they crossed the continent. Finally (on 10 March 1736) the expedition arrived at the Pacific port of Manta. La Condamine's associations with his colleagues were unhappy. The expedition was beset by many difficulties, and finally La Condamine split from the rest and made his way to Quito, Ecuador separately, becoming the first Westerner to encounter rubber in the process. He joined the group again on 4 June 1736 in the city of Quito.
The meridian (longitudinal) arc which La Condamine and his colleagues chose to measure the length of passed through a high valley perpendicular to the equator, stretching from Quito (now the capital of Ecuador) in the north to Cuenca in the south. The scientists spent a month performing triangulation measurements in the Yaruqui plains — from 3 October to 3 November 1736 — and then returned to Quito. After they had come back to Quito, they found that subsidies expected from Paris had not arrived. La Condamine, who had taken precautions and had made a deposit on a bank in Lima, traveled in early 1737 to Lima to collect money. He prolonged this journey somewhat to study the cinchona tree with its medicinally active bark (containing the anti-malarial drug quinine), the tree being hardly known in Europe.
After returning to Quito on 20 June 1737, he found that Godin refused to disclose his results, whereupon La Condamine joined forces with Bouguer. The two men continued with their length measurements in the mountainous and inaccessible region close to Quito. When in December 1741 Bouguer detected an error in a calculation of La Condamine's, the two explorers got into a quarrel and stopped speaking to each other. However, working separately, the two completed their project in May 1743.
Insufficient funds prevented La Condamine from returning to France directly. Thus La Condamine chose to return by way of the Amazon River, a route which is longer and more dangerous. His was the first scientific exploration of the Amazon. He reached the Atlantic Ocean on 19 September 1743, having made observations of astronomic and topographic interest on the way. He also made some botanical studies, notably of cinchona and rubber trees. In February 1744 he arrived in Cayenne, the capital of French Guyana. He did not dare to travel back to France on a French merchant ship because France was at war (the Austrian Succession War of 1740–1748), and he had to wait for five months for a Dutch ship, but made good use of his waiting time by observing and recording physical, biological, and ethnological phenomena. Finally leaving Cayenne in August 1744, he arrived in Amsterdam on 30 November 1744, where he stayed for a while, and arrived in Paris in February 1745. He brought with him many notes, natural history specimens, and art objects that he donated to the naturalist Buffon (1707–1788).
La Condamine published the results of his measurements and travels with a map of the Amazon in Mém. de l'Académie des Sciences, 1745 (English translation 1745–1747). This included the first descriptions by a European of the Casiquiare canal and the curare arrow poison prepared by the Amerindians. He also noted the correct use of quinine to fight malaria. The journal of his ten-year long voyage to South America was published in Paris in 1751. The scientific results of the expedition were unambiguous: the Earth is indeed a spheroid flattened at the poles as was believed by Newton. Not surprisingly, La Condamine and Bouguer failed to write a joint publication. Bouguer's death in 1758 put an end to their quarrel. The other expedition member, Godin, died in 1760. The only surviving member, La Condamine, obtained most of the credit for the expedition which drew a great deal of attention in France. Although less talented in astronomy than Godin and a lesser mathematician than Bouguer, La Condamine was a gifted writer and popularizer.
On a visit to Rome La Condamine made careful measurements of the ancient buildings with a view to a precise determination of the length of the Roman foot. He also wrote in favour of inoculation, and on various other subjects, mainly connected with his work in South America.
La Condamine had contracted smallpox in his youth. This led him to take part in the debate on vaccination against the disease and to propagate inoculation against small-pox. Assisted by the clarity and elegance of his writing, he presented several papers at the Academy of Sciences in which he defended his ideas with passion. He became a corresponding member of the academies of London, Berlin, Saint Petersburg and Bologna, and was elected to the l'Académie française on 29 November 1760. In August 1756, he married, with papal dispensation, his young niece Charlotte Bouzia of Estouilly. La Condamine had many friends, the closest one being Maupertuis, to whom he bequeathed his papers. La Condamine died in Paris on 4 February 1774, following a hernia operation.
South America 
- Journal du voyage fait par ordre du roi à l'équateur (Paris 1751, Supplement 1752)
- Relation abrégée d'un voyage fait dans l'intérieur del'Amérique méridionale (Paris 1759)
- "Mémoire sur quelques anciens monumens du Perou [sic], du tems des Incas", in: Histoire de l'Académie Royale des Sciences et Belles Lettres II (1746), Berlin 1748, S. 435–456 (hier als PDF).
- La figure de la terre déterminée (Paris 1749)
- Mesure des trois premiers degrés du méridien dans l'hémisphère australe (Paris 1751)
- Histoire de l'inoculation de la petite vérole (Amsterdam 1773)
This article incorporates material from the Citizendium article "Charles Marie de La Condamine", which is licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License but not under the GFDL.
- de la Condamine (1738) "Sur l'arbre du quinquina" (On the quinquina tree) Histoire de l'Académie royale des Sciences, pages 226-243.
- Ferreiro, Larrie (2011). Measure of the Earth: The Enlightenment Expedition that Reshaped Our World. New York: Basic Books. p. 376. ISBN 978-0-465-01723-2.
- This article incorporates text from a publication now in the public domain: Chisholm, Hugh, ed. (1911). Encyclopædia Britannica (11th ed.). Cambridge University Press.
- Victor Wolfgang von Hagen: South America called them; explorations of the great naturalists: La Condamine, Humboldt, Darwin, Spruce. New York: Knopf, 1945
- Robert Whitaker: The Mapmaker's Wife. London: Doubleday, 2004. (The full story of the expedition to South America, drawn from the original documents.)
- Neil Safier, Measuring the New World: Enlightenment Science and South America, Univ. of Chicago Press, 2008. ISBN 0-226-73355-6
- French Academy of Sciences biography
- O'Connor, John J.; Robertson, Edmund F., "Charles Marie de La Condamine", MacTutor History of Mathematics archive, University of St Andrews.