. Soon after taking his
degree of B.A., at the age of nineteen, he decided upon the profession
of medicine, and went to Padua as a pupil of Fabricius and Casserius.
Returning to England at the age of twenty-four, he soon after (1609)
obtained the reversion of the post of physician to St. Bartholomew's
Hospital, his application being supported by James I. himself. Even at
this time he was a popular physician, counting among his patients such
men as Francis Bacon. In 1618 he was appointed physician extraordinary
to the king, and, a little later, physician in ordinary. He was in
attendance upon Charles I. at the battle of Edgehill, in 1642, where,
with the young Prince of Wales and the Duke of York, after seeking
shelter under a hedge, he drew a book out of his pocket and, forgetful
of the battle, became absorbed in study, until finally the cannon-balls
from the enemy's artillery made him seek a more sheltered position.

On the fall of Charles I. he retired from practice, and lived in
retirement with his brother. He was then well along in years, but
still pursued his scientific researches with the same vigor as before,
directing his attention chiefly to the study of embryology. On June 3,
1657, he was attacked by paralysis and died, in his eightieth year. He
had lived to see his theory of the circulation accepted, several years
before, by all the eminent anatomists of the civilized world.

A keenness in the observation of facts, characteristic of the mind of
the man, had led Harvey to doubt the truth of existing doctrines as to
the phenomena of the circulation. Galen had taught that "the arteries
are filled, like bellows, because they are expanded," but Harvey thought
that the action of spurting blood from a severed vessel disproved
this. For the spurting was remittant, "now with greater, now with less
impetus," and its greater force always corresponded to the expansion
(diastole), not the contraction (systole) of the vessel. Furthermore,
it was evident that contraction of the heart and the arteries was not
simultaneous, as was commonly taught, because in that case there would
be no marked propulsion of the blood in any direction; and there was no
gainsaying the fact that the blood was forcibly propelled in a definite
direction, and that direction away from the heart.

Harvey's investigations led him to doubt also the accepted theory
that there was a porosity in the septum of tissue that divides the two
ventricles of the