Projet Coménius 2011 CASSINI

Jean-Dominique Cassini I -He was born in June 8th, 1625 in Perinaldo. -An Italian and French mathematician, astronomer, engineer and astrologer. -Professor of astronomy at the University of Bologna. -He was the first to observe the four moons of Saturne, which he called Sidera Lodoicea. And to observe differential rotation within Jupiter’s atmosphere.

-1672: Cassini and Jean Richer made simultaneous observations of Mars. -They determined its distance from the Earth. -Cassini was the first to make successful measurements of longitude ( Galileo’s methods) : A senator of Bologna invited Cassini and offered him a position in the Panzano Observatory.

-1669: Cassini moved to France. -He joined the Science Academy of Louis XIV. -He took part in the discovery of the intensity variation of gravity depending on latitude : He became deaf and blind. He died two years later in Paris.

Louis XIV -The Sun King of France. -He reigned from 1643 till this death in He was 4 years old when he became a king which means that he reigned on France for 72 years. -He led diplomacy and war : he ordered the construction of Versailles Palace. -The end of his reign provoked revolts of the French population, big famines (2 million deaths among the royal family members).

The map of France -Cassini realized a map of France in the 18th century. -It took one and a half to realize this work. (From Cassini I to Cassini IV his Great- grandson). -Casini III was the main creator of this map. -Louis XV used Cassini’s map that it was both « Precise » and « General». He was fascinated by geography and possessed a collection of maps. -Colbert : “ It was a matter of facilitating sea exchanges.” -Louis XIV: “It was a matter of war”.

-1669: Jean Picard was the first astronomer to start a large firm to design the map of France. Louis XIV was angry with his astronomers because he claimed that they had made him lose more territory than he had won wars. -The king considered to have a large territory when Cassini’s map showed a smaller territory. -Cassini trained engravers to respect the precision of lists.

-But the finance inspector warned Cassini that the spendings would be reduced because of the war : Cassini finished to set up the « French Maps Company ». -The provinces provided for 30% of the spendings. -Cassini III died in Cassini IV finished the map during the French revolution : The map was finished and given to the National Assembly to define the different French departments : It became military business : the latest papers of the collection were published.

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