In 1735, the French explorer Charles Marie de La Condamine, accompanied by the astronomer Louis Godin, the mathematician Pierre Bouguer and the botanist Joseph de Jussieu embarked on an expedition to South America to measure the length of several degrees of latitude from the equator.
Sir Isaac Newton had theorised that the Earth was not a perfect sphere, but rather bulges at the equator. This theory was controversial in France and the expedition was sent in order to work out whether Newton was correct. An earlier expedition had gathered measurements in the Arctic Circle so all that remained was to travel to the equator.
Arriving in Ecuador in March 1736, de La Condamine soon fell out with the rest of the party and set off on his own, arriving in Quito in June. In the process he became the first European to encounter rubber. Rejoining the party, they soon set off for Cuenca where a series of measurements were made.
Returning to Quito in November, the expedition discovered subsidies sent from France had not arrived, so de La Condamine made his way to Lima to collect funds that he had sent to the city in case of emergency, extending his journey to study the bark of the cinchona tree, a source of the drug quinine. Unfortunately, the specimens he collected did not survive the return journey. He did however collect seeds from other exotic plants in the region.
On his return to Ecuador in 1737, de La Condamine discovered that Godin refused to share the measurements made the previous year, leading to de La Condamine and Bouguer spending a further five years in the region finishing the project.
Despite the quarrels between the members of the party, the expedition was ultimately successful. They were able to accurately calculate the shape of the Earth and determine the strength of gravity on the planet. On the creation of the metric system in 1799, the calculations made by the expedition were used to determine the length of a metre.
This is a 1778 edition of de La Condamine's account of the expedition. While heavily biased towards his version of events, the book provided an excellent description of the journey and the biodiversity of Ecuador, which inspired future explorers such as Alexander von Humboldt.