César-François Cassini de Thury

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César-François Cassini de Thury

1714-1784

French cartographer who created the first modern map of France (1745). His project of producing an even more detailed map was almost completed before his death. Earlier in his career he sided with his father, Jacques, in defending René Descartes' prediction that Earth's polar axis is elongated against Isaac Newton's prediction that Earth is flattened at the poles. Cassini renounced the Cartesian theory after expeditions to Peru and Lapland called into question his family's earlier geodesic operations.