Jean de Chastelet

Jean du Chatelet, also known as Baron de Beausoleil and Auffembach (1578, Brabant – c. 1645, The Bastille, Paris), was a mineralogist, mining engineer and dowser.

After an early career as a soldier, du Chatelet became enthused with the study of minerals and undertook a tour of Europe visiting mines in Germany, Hungary, Bohemia, Tyrol, Silesia, Moravia, Poland, Sweden, Italy, Spain, Scotland, and England.

[1] In 1610 he married Martine Bertereau, the educated daughter of a noble family of French mine owners who accompanied him on his tours and at his work underground.

The instruments and methods that the couple employed in their mineral exploration have led to his being associated with dowsing, astrology and alchemy.

They received no reply but the charges of sorcery were resurrected and they were both imprisoned - he in the Bastille and she in the Castle of Vincennes.