Jean Fernel, or Ioannes Fernelius, one of the outstanding lights of French medicine of the sixteenth century, was born, according to Mézeray, at Montdidier; according to Plancy, at Clermont. The date of his birth is also a question of dispute, 1497, 1485 and 1506 being stated. He went to Paris in 1516 to the Collége de Sainte Barbe, where he studied philosophy, mathematics and languages and received his M.A. in 1519. He continued to study with great zeal, but a quartan fever made him leave Paris, and this may have influenced him to take up the study of medicine. He taught philosophy in his alma mater while he studied for his doctor's degree, which he received in 1530. His devotion to mathematics almost ruined him financially, as he gave up most of his time to it. Finally, at the insistence of his father-in-law, as Fernel was spending his wife's dot,