Jean Tarde (b.

La Roque-Gageac La Roque-Gageac (; ) is a commune in the Dordogne department in Nouvelle-Aquitaine, southwestern France. Perched above the river Dordogne, the village is a member of the association ''Les Plus Beaux Villages de France'' ("The most beautiful vi ...

1561 or 1562, d. La Roque-Gageac 1636) was

Vicar general A vicar general (previously, archdeacon) is the principal deputy of the bishop or archbishop of a diocese or an archdiocese for the exercise of administrative authority and possesses the title of local ordinary. As vicar of the bishop, the vica ...

of Sarlat, famous for his chronicles of the diocese. He was a Frenchman and was an early adopter of Copernican theory. Tarde was born into a semi wealthy family in the bourgeois community in

, near Sarlat, France. When he was born this was part of

Guyenne Guyenne or Guienne ( , ; ) was an old French province which corresponded roughly to the Roman province of '' Aquitania Secunda'' and the Catholic archdiocese of Bordeaux. Name The name "Guyenne" comes from ''Aguyenne'', a popular transform ...

. He received his doctorate of law from the University of Cahors and then went on to the

University of Paris The University of Paris (), known Metonymy, metonymically as the Sorbonne (), was the leading university in Paris, France, from 1150 to 1970, except for 1793–1806 during the French Revolution. Emerging around 1150 as a corporation associated wit ...

to continue his studies. Throughout his younger adult life, he held a number of different religious positions such as

canon theologian Canon () is a Christian title usually used to refer to a member of certain bodies in subject to an ecclesiastical rule. Originally, a canon was a cleric living with others in a clergy house or, later, in one of the houses within the precinct of ...

, and

almoner An almoner () is a chaplain or church officer who originally was in charge of distributing money to the deserving poor. The title ''almoner'' has to some extent fallen out of use in English, but its equivalents in other languages are often used f ...

where during his free time he studied various sciences including mathematics, astronomy, physics, and geography. He is most famous for his work with

sunspot Sunspots are temporary spots on the Sun's surface that are darker than the surrounding area. They are one of the most recognizable Solar phenomena and despite the fact that they are mostly visible in the solar photosphere they usually aff ...

s which he concluded were small satellites of the sun.

Biography

Jean Tarde belonged to an established family of Sarlat dating to a least the 14th century. The family had two branches, the du Ponts, to which Jean Tarde belonged, and the de Lisles. He studied at the university of

Cahors Cahors (; ) is a Communes of France, commune in the western part of Southern France. It is the smallest prefecture among the 13 departments that constitute the Occitania (administrative region), Occitanie Region. The capital and main city of t ...

and then at the Sorbonne, and was an expert in mathematical sciences. He became

curate A curate () is a person who is invested with the ''care'' or ''cure'' () of souls of a parish. In this sense, ''curate'' means a parish priest; but in English-speaking countries the term ''curate'' is commonly used to describe clergy who are as ...

Carves Carves (; ) is a commune in the Dordogne department in Nouvelle-Aquitaine in southwestern France. Population See also *Communes of the Dordogne department The following is a list of the 503 communes of the Dordogne department of France ...

, near

Belvès Belvès (; Languedocien: ''Belvés'') is a former commune in the Dordogne department in southwestern France. In 1973 it absorbed the former commune Fongalop. On 1 January 2016, it was merged into the new commune Pays-de-Belvès.Gallo-Roman sites. He was at

Béziers Béziers (; ) is a city in southern France. It is a Subprefectures in France, subprefecture of the Hérault Departments of France, department in the Occitania (administrative region), Occitanie Regions of France, region. Every August Béziers ho ...

and

Marseille Marseille (; ; see #Name, below) is a city in southern France, the Prefectures in France, prefecture of the Departments of France, department of Bouches-du-Rhône and of the Provence-Alpes-Côte d'Azur Regions of France, region. Situated in the ...

in 1591, at resided in

Nîmes Nîmes ( , ; ; Latin: ''Nemausus'') is the Prefectures in France, prefecture of the Gard Departments of France, department in the Occitania (administrative region), Occitanie Regions of France, region of Southern France. Located between the Med ...

and

Uzès Uzès (; ) is a commune in the Gard department in the Occitanie region of Southern France. Uzès lies about north-northeast of Nîmes, west of Avignon, and southeast of Alès. History Originally ''Ucetia'' or ''Eutica'' in Latin, Uzès wa ...

in 1592, 1593, and 1594. In 1593 he also visited

Orange Orange most often refers to: *Orange (fruit), the fruit of the tree species '' Citrus'' × ''sinensis'' ** Orange blossom, its fragrant flower ** Orange juice *Orange (colour), the color of an orange fruit, occurs between red and yellow in the vi ...

and

Avignon Avignon (, , ; or , ; ) is the Prefectures in France, prefecture of the Vaucluse department in the Provence-Alpes-Côte d'Azur region of southeastern France. Located on the left bank of the river Rhône, the Communes of France, commune had a ...

, where he was given permission to pursue his research in the pontifical archives, from where he set off in his first visit to Rome, and to where he returned. On this first visit, in 1593, he spent his time with the great antiquarian

Fulvio Orsini Fulvio Orsini (11 December 1529 – 18 May 1600) was an Italian humanist, historian, and archaeologist. He was a descendant of the Orsini family, one of the oldest, most illustrious, and for centuries most powerful of the Roman princely families ...

. It was also on this visit that he made the acquaintance of one of the finest mathematicians of the day,

Christoph Clavius Christopher Clavius, (25 March 1538 – 6 February 1612) was a Jesuit German mathematician, head of mathematicians at the , and astronomer who was a member of the Vatican commission that accepted the proposed calendar invented by Aloysius ...

. During the

Wars of Religion A religious war or a war of religion, sometimes also known as a holy war (), is a war and conflict which is primarily caused or justified by differences in religion and beliefs. In the modern period, there are frequent debates over the extent ...

the archives of the cathedral were destroyed, and Tarde was in charge of reconstituting them. In 1594 the bishop of Sarlat also commissioned him to prepare a map of the diocese, illustrating the damage caused by the wars. To undertake this task, he walked the diocese with a

quadrant Quadrant may refer to: Companies * Quadrant Cycle Company, 1899 manufacturers in Britain of the Quadrant motorcar * Quadrant (motorcycles), one of the earliest British motorcycle manufacturers, established in Birmingham in 1901 * Quadrant Privat ...

, a compass needle and a sundial to establish distances and angles. The chronicles he kept until 1630 probably date from this time as well. He also chronicled a journey to

Rome Rome (Italian language, Italian and , ) is the capital city and most populated (municipality) of Italy. It is also the administrative centre of the Lazio Regions of Italy, region and of the Metropolitan City of Rome. A special named with 2, ...

that he undertook in 1593 on the bishop's instruction. In March 1599,

Henri IV Henry IV (; 13 December 1553 – 14 May 1610), also known by the epithets Good King Henry (''le Bon Roi Henri'') or Henry the Great (''Henri le Grand''), was King of Navarre (as Henry III) from 1572 and King of France from 1589 to 16 ...

named him almoner in ordinary. In 1629, Tarde was made a member of the

Conseil du Roi The (; 'King's Council'), also known as the Royal Council, is a general term for the administrative and governmental apparatus around the King of France during the Ancien Régime designed to prepare his decisions and to advise him. It should no ...

, a hereditary position retained by his family until the French Revolution. Jean Tarde considered sunspots to be tiny planets between Mercury and the sun. His religious beliefs prevented him from accepting that sunspots appeared on the Sun itself because the Sun was a sacred place chosen by God himself and it could not be corrupt. This theory was grounded in the biblical phrase "In sole posuit tabernaculum Suum" (‘ odhas pitched his tent in the sun’) which he referred to in his writing. The idea of the Sun being pure and sacred was based not only in the bible but in the philosophy of Aristotle.

Astronomy

Discussions with
Galileo Galilei Galileo di Vincenzo Bonaiuti de' Galilei (15 February 1564 – 8 January 1642), commonly referred to as Galileo Galilei ( , , ) or mononymously as Galileo, was an Italian astronomer, physicist and engineer, sometimes described as a poly ...

First learning of Galileo's work through Robert Balfour who knew him, Jean Tarde read

Sidereus Nuncius ''Sidereus Nuncius'' (usually ''Sidereal Messenger'', also ''Starry Messenger'' or ''Sidereal Message'') is a short astronomical treatise (or ''pamphlet'') published in Neo-Latin by Galileo Galilei on March 13, 1610. It was the first published ...

and wanted to find out more. During his visit to Florence, Jean Tarde went to see Galileo in 1614, November 12. Tarde admired Galileo writing in his own diary after the encounter, "In the morning I went to see Master Galileo, famed philosopher and astronomer.... I told him that his fame had crossed the Alps, traversed France, and reached even to the ocean." In their conversation, he talked with Galileo about several topics such as the "moons" (ring) of Saturn and phases of Venus. Galileo believed that the spots traveled the same path as Venus and Mercury taking 14 days to cross the middle of the earth. Galileo also felt that there was no parallax for the spots, meaning the spots had to be very close to or on the sun, not the earth. He knew his claims may have been hard to believe, so Galileo also told Tarde that others had seen the same spots he had seen, which in effect helped validate his sightings. Later in their conversation, Tarde asks Galileo how to make a telescope. Galileo claimed to now know how the scope worked, but he did reference Tarde to Kepler's book on optics. Galileo was supposed to send Tarde better lenses while Tarde was in Rome, however months went by and he still had not (this was known by Tarde's letters to Galileo). However Tarde and Galileo encountered each other a few times after their conversation and Galileo revealed more and more about what he had discovered with the telescope. Jean Tarde wrote about his meeting and discussion with Galileo in his diary. However, the section of the interview in which he had discussed sunspots with Galileo was crossed out. The reasons Jean Tarde did this is unknown and are a subject of debate among historians. Some historians have suggested that Jean Tarde learned that Galileo was not the first to discover sunspots as he had claimed at the time. Galileo and Tarde met up a few times after this.

Discussions with
Christoph Grienberger Christoph (Christophorus) Grienberger (also variously spelled Gruemberger, Bamberga, Bamberger, Banbergiera, Gamberger, Ghambergier, Granberger, Panberger) (2 July 1561 – 11 March 1636) was an Austrian Jesuit astronomer, after whom the crate ...

After meeting with Galileo in Florence, Jean Tarde went to back to Rome where he meet the Jesuit mathematician Christoph Grienberger. Jean Tarde learned several more things about sunspots from Christoph Grienberger. Among these Christoph Grienberger told Jean Tarde that numerous other astronomers in both Italy and Germany had been able to observe the sunspots. Christoph Grienberger explained that there were two main threads of thought about what sunspots were; he said that people either thought sunspots were small planets extremely close to the Sun or some sort of phenomena in the Sun's atmosphere. He also demonstrated four methods of observing sunspots to Jean Tarde. Diagram of Sunspots from Borbonia Sidera

Diagram of Sunspots from Borbonia Sidera

Research at Sarlat

Jean Tarde returned to Sarlat in 1615 February and constructed a small observatory. It is unknown if the telescope he used the lens promised by Galileo. Jean Tarde made observations by casting a projection of the Sun onto a white sheet inside his darkened observatory. Using this method he took long and detailed logs of sunspots and their movements. These records would be used several years later when writing his book. In 1615 August 25 Jean Tarde observed over 30 sunspots on the face of the Sun at once.

"The Bourbon Planets"

Jean Tarde started writing his book on sunspots in 1619. He eventually published two versions of the book on the topic: ''Borbonia Sidera'' in Latin in 1620 and ''Astras de Borbon'' in French in 1622. The titles of these books mean "Bourbon Stars", dedicated to

Louis XIII Louis XIII (; sometimes called the Just; 27 September 1601 – 14 May 1643) was King of France from 1610 until his death in 1643 and King of Navarre (as Louis II) from 1610 to 1620, when the crown of Navarre was merged with the French crown. ...

and the ruling family of France; likely in order to try to gain patronage, like many other scientists of the time. How Multiple Planets can Make Shapes Like Sunspots

How Multiple Planets can Make Shapes Like Sunspots

In these books Tarde lays out his observations and arguments about the nature of the recently discovered sunspots. Tarde refutes the theory that the spots were on the Sun or in the Sun's atmosphere by claiming this "violates the Aristotelian principle that the heavens were not subject to corruption". The Peripatetics felt the claim was outrageous and offensive. Tarde says the spots are actually clouds and emissions from the Sun. Tarde argued that spots can not diminish the Sun because the Sun is the father of light. He states, "It is the seat of God, His house, His tabernacle. It is impious to attribute to God's house the filth, corruption and blemishes of the Earth." Tarde felt the Sun was a perfect sphere and was flawless. Instead, Tarde favored the view that sunspots were instead a series of small planets orbiting closely to the Sun. In his book he laid out a series of twenty properties of the sunspots which he believed lead to the conclusion that sunspots were planets. Among the properties he cited were: * The number of sunspots and the frequency of their appearance were far to great to be transits of the other inner planets; Venus and Mercury. He even pointed out that an observation of Kepler's, "a little daub, quite black, approximately like a flea," which Kepler thought was a transit of Mercury was actually a sunspot. He made similar claims about observations by

Julius Caesar Scaliger Julius Caesar Scaliger (; 23 April or August 1484 – 21 October 1558), or Giulio Cesare della Scala, was an Italian scholar and physician, who spent a major part of his career in France. He employed the techniques and discoveries of Renaissance ...

. * He compared the darkness that the sunspots on the Sun were similar in darkness to that of the shadow of the Earth on the Moon during a

lunar eclipse A lunar eclipse is an astronomical event that occurs when the Moon moves into the Earth's shadow, causing the Moon to be darkened. Such an alignment occurs during an eclipse season, approximately every six months, during the full moon phase, ...

. * Many people at the time held to the view that the seven planets known to the ancients; Mercury,

Venus Venus is the second planet from the Sun. It is often called Earth's "twin" or "sister" planet for having almost the same size and mass, and the closest orbit to Earth's. While both are rocky planets, Venus has an atmosphere much thicker ...

Mars Mars is the fourth planet from the Sun. It is also known as the "Red Planet", because of its orange-red appearance. Mars is a desert-like rocky planet with a tenuous carbon dioxide () atmosphere. At the average surface level the atmosph ...

Jupiter Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a Jupiter mass, mass more than 2.5 times that of all the other planets in the Solar System combined a ...

Saturn Saturn is the sixth planet from the Sun and the second largest in the Solar System, after Jupiter. It is a gas giant, with an average radius of about 9 times that of Earth. It has an eighth the average density of Earth, but is over 95 tim ...

, the

Moon The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar ...

, and the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

. Jean Tarde asserted that this belief was wrong by discussing how several ancient cultures believed in an infinite number of worlds. Although he didn't actually believe there was an infinite number of worlds he did cite the recent discoveries of the Jupiter's

Galilean moons The Galilean moons (), or Galilean satellites, are the four largest moons of Jupiter. They are, in descending-size order, Ganymede (moon), Ganymede, Callisto (moon), Callisto, Io (moon), Io, and Europa (moon), Europa. They are the most apparent m ...

and Saturn's two moons (actually rings). He also cited the vast number of new stars visible now through telescopes. * He asserted that sunspots could not be stars because were not luminous like other stars. * He argued against Galileo's proof that sunspots were not planets because of their irregular shape using several claims. Including, that the brightness of the Sun made it impossible to get a clear picture of the sunspots' roundness, that current telescopes had issues with resolving dim and far away objects, and that the sunspots would be undergoing

phases Phase or phases may refer to: Science *State of matter, or phase, one of the distinct forms in which matter can exist *Phase (matter), a region of space throughout which all physical properties are essentially uniform *Phase space, a mathematica ...

like the other inner planets. * He argued that apparent motion across the

ecliptic The ecliptic or ecliptic plane is the orbital plane of Earth's orbit, Earth around the Sun. It was a central concept in a number of ancient sciences, providing the framework for key measurements in astronomy, astrology and calendar-making. Fr ...

was caused by the angle of viewing of the observer standing on the Earth. * Galileo had argued that sunspots must have to be on the Sun because they show no

parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different sightline, lines of sight and is measured by the angle or half-angle of inclination between those two lines. Due to perspective (graphica ...

. In response Tarde argued that they were either too close to the Sun to get an accurate measurement or that the change in parallax was so slight that it would have to have constant monitoring. Thus even one cloudy day would prevent its measurement. * One large problem which Galileo had posed to Tarde was that the Venus'

orbit In celestial mechanics, an orbit (also known as orbital revolution) is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an ...

was quicker than Earth's and Mercury's faster than Venus' so why didn't the sunspots go faster? In response, Tarde argued that the variable speeds of the sunspots was part of how they could be identified. * He also thought that the Sun was incorruptible. Through Tarde had many findings, it was not until years after he made discoveries that he published his work unlike the other philosophers of his time. Though Tarde had put so much time and effort into his work, the recognition he wished to have gained from the king was not presented to him. He even abandoned the sunspots theory for a couple of years where he then returned to the conversation in ''Dialogue on the two world systems of 1632''. In later years, several philosophers began to discuss Tarde's work. Some agreed with Tarde, some disagreed, but the discussion was still happening. However, once Tarde died, so did the conversation about sunspots. In the following years, some sightings of sunspots were found in 1640 and the conversation began again.

Published works

''Chroniques de Jean Tarde''

''Les usages du quadrant à l'esguille aymantée divisée en deux livres'', 1621
* ''Borbonia sidera, id est Planetae qui solis limina circumvolitant motu proprio ac regulari, falso hactenus ab helioscopis maculae solis nuncupati. Ex novis observationibus Joannis Tarde'', 1620
''Les Astres de Borbon et apologie pour le soleil, monstrant et vérifiant que les apparences qui se voyent dans la face du soleil sont des planètes, et non des taches'', 1622

''Description du diocèse de Sarlat et Haut Périgord'', 1624

''Le diocèse de Sarlat. Diocoesis Sarlatensis'', 1625

''Potamographie de Garone et des fleuves qui se rendent dedans''

''Description du pais de Quercy''

References

Bibliography

* Gaston de Gérard,

Gabriel Tarde Jean-Gabriel (de) Tarde (; ; 12 March 1843 – 13 May 1904) was a French sociologist, criminologist and social psychologist who conceived sociology as based on small psychological interactions among individuals (much as if it were chemist ...

, éditeur scientifique et préfacier de ''Les chroniques de Jean Tarde'', , H. Oudin, Paris, 188
(''lire en ligne'')
* A. Dujarric-Descombes, ''Recherches sur les historiens du Périgord au XVIIe siècle - Tarde'', , Bulletin de la Société historique et archéologique du Périgord, 1882, tome
(''lire en ligne'')
* Auguste Molinier, ''Les Chroniques de Jean Tarde..., par Gabriel Tarde'', , Bibliothèque de l'école des chartes, 1888, nº 49 {{DEFAULTSORT:Tarde, Jean 1562 births 1636 deaths 16th-century French scientists People from Sarlat-la-Canéda 16th-century French historians 16th-century French male writers 17th-century French astronomers People from Guyenne