Vein valves

Discovery that veins have valves that prevent backflow. Galen’s doctrine was that blood was made in liver, carried to heart and pumped through arteries and veins. Fabrici found something else but didn’t dare to go against Galen.
 Girolamo Fabrici Italy 1603 Vein valves

Discovery that veins have valves that prevent backflow. Galen’s doctrine was that blood was made in liver, carried to heart and pumped through arteries and veins. Fabrici found something else but didn’t dare to go against Galen.