William Harvey, English physician and academic (died 1657)

William Harvey was an English physician who made influential contributions to anatomy and physiology. He was the first known physician to describe completely, and in detail, pulmonary and systemic circulation as well as the specific process of blood being pumped to the brain and the rest of the body by the heart.

April 1 is the 91st day of the year in the Gregorian calendar; 274 days remain until the end of the year.