Jorge Juan y Santacilia
Jorge Juan y Santacilia | |
|---|---|
 Portrait by Rafael Tegeo | |
| Born | 5 January 1713 Novelda, Spain |
| Died | 21 June 1773 (aged 60) Madrid, Spain |
| Nationality | Spanish |
| Alma mater | Royal Company of Marine Guards |
| Known for | Figure of the earth |
| Awards | Corresponding member of the Royal Academy of Sciences of Paris (1745), Fellow of the Royal Society of London (1749), member of the Royal Academy of Sciences of Berlin (1750) |
| Scientific career | |
| Fields | Geodesy, Naval architecture, Astronomy, Mathematics |
| Institutions | Spanish Navy, Seminary of Nobles of Madrid |
| Military service | |
| Allegiance |  Kingdom of Spain |
| Branch/service | Spanish Navy |
| Rank | Captain |
| Battles/wars | Conquest of Oran Battle of Bitonto War of Jenkins' Ear |
Jorge Juan y Santacilia (Novelda, Alicante, 5 January 1713 – Madrid, 21 June 1773) was a Spanish mariner, mathematician, natural scientist, astronomer, and engineer. He is generally regarded as one of the most important scientific figures of the Enlightenment in Spain, remembered for both his intellectual and his practical contributions to the Bourbon Reforms of the 18th century. As a military officer, he undertook sensitive diplomatic missions for the Spanish crown and contributed to the modernization and professionalization of the Spanish Navy.
As a young naval lieutenant, Juan participated in the French Geodesic Mission to the Equator of 1735–1744, thus helping to establish that the shape of the Earth is an oblate spheroid, flattened at the poles, as predicted in Isaac Newton's Principia. With his fellow lieutenant Antonio de Ulloa, Juan travelled widely in the territories of the Viceroyalty of Peru, allowing them to make detailed scientific, military, and political observations. They also helped to organize the defense of the Peruvian coast against the English squadron of Commodore Anson, after the outbreak of the War of Jenkins' Ear in 1739.
Back in Spain, Juan worked tirelessly to modernize and professionalize naval architecture and other operations. As a mathematician and educator, Juan promoted the study and application of the infinitesimal calculus at a time when the subject was not taught in Spanish universities. He also served as ambassador plenipotentiary to the Sultan of Morocco in 1766–67, and as director of the Seminary of Nobles of Madrid from 1770 until his death.
Family and education
Jorge Juan was born of two distinguished hidalgo families: his father was don Bernardo Juan y Canicia, a relative of the Counts of Peñalba, while his mother was doña Violante Santacilia y Soler de Cornellá, who came from a prominent land-owning family in Elche. Both of his parents were widowed and had several children from their first marriages. Jorge Juan was born on the estate El Fondonet, owned by his grandfather don Cipriano Juan Vergara, in Novelda, a town in the province of Alicante. He was baptised in the church of the neighboring town of Monforte del Cid. They lived in a home on the Plaza del Mar in the city of Alicante and vacationed in Novelda.
Jorge Juan's father died when the child was only two years old.[1] Jorge received his first education at the Jesuit school in Alicante, later studying grammar in Zaragoza as preparation for a higher education. His uncle Cipriano Juan, a Knight of the Order of Malta (also known as the "Order of Saint John") took charge of young Jorge's education. Thanks to the influence of his uncle, at the age of twelve Jorge was admitted to the Order of Saint John and traveled to the island of Malta to serve as page to Grand Master António Manoel de Vilhena. Juan stayed in Malta for almost four years. There he took religious vows as a knight, which imposed upon him the requirement of lifelong celibacy. In 1729, at the age of sixteen, Juan received from the Grand Master the title of Commander of Aliaga (Comendador de Aliaga), an honorary rank that he held for the rest of his life.
Juan then returned to Spain and applied for admission to the Royal Company of Marine Guards, the Spanish naval academy. He entered the academy in 1730 and proceeded to study modern technical and scientific studies subjects such as geometry, trigonometry, astronomy, navigation, hydrography, and cartography. He also completed his education in the humanities with classes in drawing, music, and dancing. He earned a reputation as a brilliant student and his fellow students nicknamed him "Euclid". He finished his studies at the academy in 1734. At the young age of 22, he was given command of a corvette and he participated in the expedition against Oran and in the Battle of Bitonto.
Sojourn in South America
As a result of the long-running debate between Cartesians and Newtonians over the figure of the Earth, the French Academy of Sciences decided to sponsor two geodesic expeditions: the first to measure the length of an arc of longitude near the Arctic Circle, and the other to conduct a similar measurement near the Equator. The Arctic expedition was led by Pierre Louis Maupertuis and successfully carried out its measurements in 1736–1737 in a part of Lapland that was then part of the Kingdom of Sweden.
The only feasible location for the equatorial expedition was in the Audiencia of Quito (in what is now the country of Ecuador), which was part of the Viceroyalty of Peru, under the Spanish Crown. In 1734, King Philip V of Spain agreed to allow the French expedition to visit Quito, under the condition that the French scientists should be joined by two Spanish naval officers. Upon the recommendation of his First Secretary of State José Patiño, Philip appointed to that role Jorge Juan and Antonio de Ulloa, who were 21 and 18 years old, respectively, and who were promoted to the rank of naval lieutenant (teniente de navío) so that they would have the same seniority as the French naval officers accompanying the expedition to Quito.
The Quito expedition was under the command of French astronomer Louis Godin. It also included geographers Charles Marie de La Condamine and Pierre Bouguer, and naturalist Joseph de Jussieu.[2] On 26 May 1735, they left Cadiz in the company of the Marquess of Villagarcía, who had just been appointed as the new Viceroy of Peru.
The early work of the French Geodesic Mission was hindered by lack of cooperation from the local Spanish authorities. In 1737, a personal dispute between Ulloa and the president of the Audiencia de Quito, Joseph de Araujo y Río, caused Araujo to order the arrest of both Ulloa and Juan, while announcing his intention to have them killed.[3] The young officers took refuge in a church and Ulloa then escaped through the cordon of Araujo's men, reaching Lima and obtaining the protection of the Viceroy.[3] The expedition also had to contend with the harsh climate and topography of the region, tropical diseases, and with the suspicions of the local population. In 1739 surgeon Jean Seniergues, one of the French members of the mission, was killed by a mob in the bullring of the town of Cuenca.
When the War of Jenkins' Ear broke out between Spain and Great Britain in 1739, Juan and Ulloa were tasked with organizing the defense of the Peruvian coast against the squadron of British Commodore Anson.[3] The work of the geodesic mission finally concluded after nine year. Its measurements, together with those of the Artic expedition led by Maupertuis, established unequivocally that the Earth is an oblate spheroid, i.e. flattened at the poles, as Newton had predicted. Juan also successfully used a barometer to measure the heights of several of the peaks of the Andes, based on the formulas developed for that purpose by Edme Mariotte and Edmond Halley.[1]
Return to Spain
At the end of 1744, Juan and Ulloa embarked for Europe on two different French ships, each carrying their own copies of their scientific and other papers, in order to minimize the risk that their work would be lost in the homeward journey. At the time, Great Britain was at war with both France and Spain, and Ulloa's ship was captured by the British Navy. Initially held as a prisoner of war in Portsmouth, Ulloa's scientific work attracted the attention of the new First Lord of the Admiralty, the Duke of Bedford. Bedford allowed Ulloa to travel to London, where Ulloa was elected as fellow of the Royal Society. Thank to the intervention of the President of the Royal Society, Martin Folkes, Ulloa was eventually allowed to continue on to Spain.
Juan, for his part, landed safely in Brest on October 1745. Juan then travelled to Paris, where his contribution to the Geodesic Mission was rewarded by election as corresponding member of the French Academy of Sciences. Juan finally arrived in Spain at the start of 1746, a few months ahead of Ulloa.[1] They were both promoted to the rank of frigate captain (capitán de fragata).
Juan and Ulloa jointly published several works based on their South American observations. Juan, who was the more mathematically inclined of the two, was largely responsible for writing the Astronomical and Physical Observations Made by Order of His Majesty in the Kingdoms of Peru, which contained his calculations of the figure of the Earth. The publication of the book was held up by the Spanish Inquisition because Juan worked within the framework of the heliocentric cosmology, which the Catholic church still officially regarded as heretical after the condemnation of Galileo more than a century earlier.[1] The Inquisition allowed the publication of the book to proceed in 1748, after Juan modified the text to present heliocentrism as a mere hypothesis adopted for purposes of calculation.
Ulloa, for his part, wrote most of the four volumes of the Historical Report of the Voyage to Southern America, which also appeared in 1748. Both authors collaborated in the composition of the Historical and Geographical Dissertation on the Demarcation Meridian between the Dominions of Spain and Portugal, published in 1749.[1] The purpose of that work was to determine precisely the line of demarcation as defined by the terms of the Treaty of Tordesillas between Spain and Portugal, signed in 1494 under the sponsorship of Pope Alexander VI.
Juan and Ulloa also jointly signed a confidential report, written by Ulloa around 1746 and addressed to the Marquess of Ensenada, who was Ferdinand VI's new Secretary of State. That report, titled Discourse and Political Reflections on the Present State of the Kingdoms of Peru, remained unknown to the public until it was published in London in 1826 by an otherwise obscure Englishman, David Barry, under the title Noticias secretas de América ("Secret News from America").[4] That report paints a dire picture of the social and political situation of the Viceroyalty of Peru in 1730s and 1740s, alleging many grave instances of lawlessness and mismanagement by the civil and church authorities in the region. It also denounces in very strong terms the exploitation of the Native American population by unscrupulous governors (especially the corregidores) and priests (especially the members of the mendicant orders). The importance and reliability of that confidential report have been subjects of enduring controversy among historians of Spanish America.[4]
In March of 1749, the Marquess of Ensenada gave Juan a sensitive mission of industrial espionage in England. Juan traveled to London incognito as "Mr. Joseus", communicating back to Ensenada using a numerical cipher. Juan's principal task was to learn about the design of the latest British warships and to recruit some of the constructors in order to help the Spanish Navy to improve its outdated fleet. He was also tasked with collecting information about the English manufacture of fine cloth, sealing wax, printing plates, dredges, and armaments, to purchase surgical instruments for the Royal College of Naval Surgeons, in Cádiz, and to procure steam engines to pump water out of mines.
In London, Juan befriended Admiral Anson and the Duke of Bedford. In November 1749 was elected as a fellow of the Royal Society.[5] With the help of a Catholic priest, Father Lynch, Juan was able to recruit about fifty naval artisans and workmen who defected to Spain. Some of these men (including Matthew Mullan and Richard Rooth) went on to build the Spanish ships that would later fight in the American Revolutionary War and at the battle of Trafalgar.
In 1750, Juan was elected as member of the Prussian Academy of Sciences upon the recommendation of its director, Pierre Louis Maupertuis. Maupertuis had been one of the key figures in the determination of the figure of the Earth from geodesic measurements and was therefore aware of Juan's contribution to that effort and of his mathematical skill. After eighteen months in England, Juan finally fled the country to avoid arrest as a foreign spy.
Back in Spain, Juan was promoted to the full rank of captain captain (capitán de navío). The Marquess of Ensenada then put him in charge of all naval construction. Juan established his own system of shipbuilding, approved by the authorities in 1752. He carried out major improvements of the military shipyards, including those in Cartagena, Cádiz, Ferrol, and Havana. He implemented a modern industrial system of division of labor among the different disciplines involved in the construction of warships, such as dry-docks, shipyards, furnaces, rigging, and canvas making. Juan also modernized the armaments used by the navy.
Juan was chiefly concerned to build ships with the least possible expenditure of wood and iron consistent with the vessel's stability. Among the warships built under Juan's "English system" were the Oriente (1753) and the Aquilón (1754). However, after the Marquess of Ensenada fell from power in 1754, Juan's methods started to be abandoned in favor of the "French system" promoted by Julián de Arriaga, the new Secretary of the Navy.
Scientific and educational efforts
During Juan's lifetime, the universities in Spain were wholly controlled by the Catholic Church and offered no modern scientific instruction. Juan promoted the teaching of differential and integral calculus in the Spanish military academies and helped to supply those institutions with modern scientific equipment.[1] In 1752, the King appointed Juan as Captain of the Royal Company of Marine Guards (Capitán de la Real Compañía de Guardias Marinas), which effectively put him in control of the Naval Academy in Cádiz. Juan appointed the French astronomer Louis Godin, with whom he had worked during the geodesic mission to South America, as director of the Academy. Together, in 1753 Juan and Godin established Spain's first astronomical observatory, the Royal Naval Observatory.[1] In 1757, Juan published a new textbook for the navigational instruction of the Academy's cadets, titled Navigational Compendium.
Juan was a corresponding member of the French Academy of Sciences (since 1745), a fellow of the Royal Society of London (since 1749), and a member of the Prussian Academy of Sciences (since 1750). In 1755, Juan founded the Asamblea Amistosa Literaria de Cádiz ("Friendly Literary Assembly of Cádiz"), which for several years met every Thursday to discuss various intellectual subjects, and which was composed principally of teachers of the Naval Academy. Juan's goal was to lay the groundwork for the future establishment of a Spanish Academy of Sciences, something that came about only in 1847, long after Juan's death.
In 1770, King Charles III appointed Juan as director of the Seminary of Nobles in Madrid. That institution had been created in 1725 by Philip V to train the children of Spain's aristocracy in military and civil administration, but it had gone into a steep decline after the expulsion of the Jesuits (who had been in charge of the Seminary) in 1767. As its director, Juan succeeded in overhauling the faculty, modernizing the curriculum, and increasing the student enrollment.[1]
Juan's principal scientific work was the Maritime Examination, published in two volumes in 1771. That work was principally concerned with practical naval architecture, but it also contained Juan's own original work on the theory of water's resistance to a ship's motion and of the generation of shock waves.[1] Juan criticized Leonhard Euler's theory of fluid resistance, which was based on the impact of the water flow upon the ship's solid surface, and proposed an alternative based on the action of gravity.[6] Both Euler's and Juan's theories were eventually found to be incorrect and have been superseded by the modern theory based on viscosity.
Further military and diplomatic appointments
In 1760 Juan was appointed as Squadron Chief of the Royal Navy (Jefe de Escuadra de la Real Armada), making him the most senior Naval officer in Spain. Shortly after that, Juan began to suffer from a biliary colic that forced him to retire temporarily to the spa town of Busot, in his native province of Alicante. In 1766–67, he served as ambassador plenipotentiary to the Sultan of Morocco, Mohammed ben Abdallah, for the purpose of concluding the peace treaty between Spain and Morocco. After concluding those negotiations successfully, Juan returned to Madrid. In 1768, Juan was again forced to seek relief for his health ailments, this time at the baths in Trillo. His last official appointment was as director of the Seminary of Nobles in Madrid.
Death and posterity
.jpg)
Jorge Juan died in Madrid in 1773 at the age of 60. His reported symptoms, including muscle stiffness and seizures, may have resulted from a cerebral amebic infection. He was buried in the church of San Martín. In 1860 he was re-buried in the Pantheon of Illustrious Sailors in Cádiz.
Among other posthumous honours, a mayor street in the Salamanca district of Madrid and a Churruca-class destroyer of the Spanish Navy were named after him.[7] In the last series of peseta banknotes (the Spanish currency before the adoption of the euro in 2002), the highest denomination bill (10,000 pesetas) carried Juan's portrait on the reverse side.
Works
- Observaciones astronomicas y phisicas (in Spanish). Madrid: Juan de Zuņiga. 1747.
- Compendio de navegación (1757)
- Examen marítimo teórico-práctico (1771)
- Estado de la astronomía en Europa (1774)
In collaboration with Antonio de Ulloa
- Plan del camino de Quito al río Esmeraldas, según las observaciones astronómicas de Jorge Juan y Antonio de Ulloa (1736–1742)
- Observaciones astronómicas y físicas hechas en los Reinos del Perú (Madrid, 1748)
- Relación histórica del viaje hecho de orden de su Majestad a la América Meridional (Madrid, 1748)
- Disertación Histórica y Geográfica sobre el Meridiano de Demarcación entre los dominios de España y Portugal (1749)
- Noticias Secretas de América, sobre el estado naval, militar y político del Perú y provincia de Quito (The Secret news of America, on the naval state, military and political of the Peru and province of Quito) (1748) (published in London 1826 after publication was banned by the Spanish government)
References
- ^ a b c d e f g h i Alberola, Armando; Die, Rosario; Goberna, Miguel A. (2023). "Jorge Juan: Mathematician, Seaman, Engineer, Diplomat, and Spy of the Spanish Enlightenment". Math. Intelligencer. doi:10.1007/s00283-023-10289-z.
- ^ Safier, Neil (2008). Measuring the New World: Enlightenment Science and South America. Chicago: University of Chicago Press. pp. 6. ISBN 978-0-226-73355-5.
- ^ a b c Whitaker, Arthur P. (1935). "Antonio de Ulloa". Hisp. Am. Hist. Rev. 15 (2): 155–194. doi:10.2307/2506293. JSTOR 2506293.
- ^ a b Juan, Jorge; de Ulloa, Antonio (1978). John J. TePaske (ed.). Discourse and political reflections on the Kingdoms of Peru. University of Oklahoma Press. ISBN 0806114827.
- ^ "Library and Archive". Royal Society. Retrieved 6 August 2012.
- ^ Simón Calero, Julián. The Genesis of Fluid Mechanics, 1640–1780. Dordrecht: Springer. pp. 182–184. ISBN 978-1-4020-6413-5.
- ^ Tudón Presas, Rafael. "Jorge Juan y Santacilia, Oficial y Científico al Servicio de la Armada" (PDF). Armada Española (in Spanish).
Further sources
- Biography – Jorge Juan Foundation
- Ferreiro, Larrie: Measure of the Earth: The Enlightenment Expedition that Reshaped Our World (New York: Basic Books, 2011) ISBN 978-0-465-01723-2[1]
- Jorge Juan. Polymath Virtual Library, Fundación Ignacio Larramendi
External links
| International | |
|---|---|
| National | |
| Academics | |
| People | |
| Other | |
- ^ 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. Archived from the original on 22 February 2014.