Mydorge, Claude

1. Dates 
Born: Paris, 1585 
Died: Paris, July 1647 
Dateinfo: Dates Certain 
Lifespan: 62

2. Father 
Occupation: Lawyer, Government Official

Mydorge belonged to one of France's richest and most illustrious families. His father was conseiller at the Parlement of Paris and Judge of the Grand Chambre. His mother was the sister of the "président Chrétien de Lamoignon."

3. Nationality 
Birth: French 
Career: French 
Death: French

4. Education 
Schooling: No University

5. Religion 
Affiliation: Catholic

6. Scientific Disciplines 
Primary: Mathematics, Optics 
Subordinate: Astronomy

His work in geometry was directed to the study of conic sections. His work on the subject, first published in two volumes in 1631 and enlarged to four in 1639, was reprinted several times under the title De sectionibus conicis. His works on conic sections contain hundreds of problems published for the first time, as well as a multitude of ingenious and original methods that later geometers frequently used. According to Baillet, he succeeded Viète as the premier mathematician of his day.

He studied the properties and nature of light and refraction, and he studied vision.

He also carried out extensive astronomical observations.

7. Means of Support 
Primary: Personal Means 
Secondary: Government

He pursued a legal career. He was, first, conseiller at the Chatelet, then treasurer of the generalité of Amiens (which appears to have been nothing more than a title to hold).

Mydorge had such extensive personal means that he could afford to devote his activities to mathematics.

In 1613 he married the sister of La Haye, the French ambassador to Constantinople.

8. Patronage 
Type: None

9. Technological Involvement 
Types: Cartography, Navigation

He determined the latitude of Paris with great precision.

He was a member of the commission appointed to judge Morin's method of determining longitude.

10. Scientific Societies 
Memberships: None

Intimate friendship with Descartes. Mydorge met Descartes about 1625 and became one of his most faithful friends. In 1627 Mydorge spent more than 100,000 ecus to make various lenses and optical instruments for Descartes, to aid him in his search for an explanation of vision. He also played a role in the reconciliation between Descartes and Fermat after 1638.

Sources 
Biographie universelle, 29, (Paris, 1860), 666. CT153.B6 
Nouvelle biographie générale, 37, 88. 
M. Cantor, Vorlesungen uber Geschichte der Mathematik, 2, (Leipzig, 1913), 673-4, 768-9. QA26.C2 
P. Humbert, "Les astronomes françaises de 1610 à 1667," Bulletin de la Société d'études scientifiques et archéologiques de Draguignan et du Var, 42 (1942), pp. 5-72.