(John), physician to Henry II. king of France, was born in Picardy, in the latter end of the 15th or the beginning of the 16th century. Being sent to Paris to study rhetoric and philosophy, he applied himself in a most intense manner. All other pleasure was insipid to him. He cared neither for play nor for walking, nor for entertainments, nor even for conversation. He read Cicero, Plato, and Aristotle. The reading of Cicero procured him this advantage, that the lectures he read on philosophical subjects were as eloquent as those of the other matters were barbarous at that time. He also applied himself very earnestly to the mathematics. This continual study drew upon him a long fit of sickness, which obliged him to leave Paris. On his recovery, he returned thither with a design to study physic; but before he applied himself entirely to it, he taught philosophy in the college of St Barbara. After this he spent four years in the study of physic; and taking a doctor's degree, confined himself to his closet, in order to read the best authors, and to improve himself in the mathematics; that is, as far as the business of his profession would suffer him. Never was a man more diligent than Fernel. He used to rise at four o'clock in the morning, and studied till it was time either to read lectures or to visit patients. He then examined the urine that was brought him; for this was the method of those times, with regard to the poor people, who did not send for the physician. Coming home to dine, he shut himself up among his books till they called him down to table. Rising from table, he returned to his study, which he did not leave without necessary occasions. Coming home at night, he did just as at noon; he staid among his books till they called him to supper; re- Fernelius turned to them the moment he had supped; and did not leave them till eleven o'clock, when he went to bed. In the course of these studies, he contrived mathematical instruments, and was at great charges in making them. But his wife murmuring at the expense, he dismissed his instrument-makers, and applied himself in good earnest to practise physic. But as visiting patients did not employ his whole time, he read public lectures upon Hippocrates and Galen. This soon gained him a great reputation through France and in foreign countries. His business increasing, he left off reading lectures; but as nothing could make him cease to study in private, he spent all the hours he could spare in composing a work of physic, intitled *Phytologia*, which was soon after published. He was prevailed with to read lectures upon this new work, which he did for three years: and undertaking another work, which he published, *De venae sectione*, he laid himself under a necessity of reading lectures some years longer, in order to explain this new book to the youth. While he was thus employed, he was sent for to court, in order to try whether he could cure a lady, whose recovery was despaired of. He was so happy as to cure her; which was the first cause of that esteem which Henry II. who was then but dauphin, and was in love with that lady, conceived for him. This prince offered him, even then, the place of first physician to him; but Fernel, who infinitely preferred his studies to the hurry of a court, would not accept the employment. When Henry came to the throne, he renewed his intrigues; but Fernel represented, that the honour which was offered to him was due, for several reasons, and as an hereditary right, to the late king's physician; and that, as for himself, he wanted some time to make experiments concerning several discoveries he had made relating to physic. The king admitted this: but as soon as Francis I.'s physician died, Fernel was obliged to go and fill his place at Henry II.'s court. And here just the contrary to what he dreaded came to pass; for he enjoyed more rest and more leisure at court than he had done at Paris; and he might have considered the court as an agreeable retirement, had it not been for the journeys which the new civil war obliged the king to take. He died in 1558, leaving behind him a great many works, besides what have been mentioned; as, *De abditis rerum causis*, seven books of Pathology; a book on Remedies, &c. They have been printed several times; with his life prefixed, written by William Plautius his disciple.