What discovery of the 17th century helped establish the science of physiology?

The English physician William Harvey (1578–1657) published On the Movement of the Heart and Blood in Animals in 1628. This important medical treatise proved that blood continuously circulated within the vessels. Harvey’s discoveries contradicted many beliefs about blood circulation that dated back to the time of Galen. Harvey is considered the father of modern physiology for introducing the experimental method of scientific research.