A short introduction to the history

The interest in the circulatory system is ancient; one of the first documented studies was performed by Herophilus (335-280 BCE). He invented a type of water clock to be able to quantify how fast the heart was beating; considering the limited knowledge of the cardiovascular system at this time, this was an advanced study for its time. Later, but still almost 2000 years ago, the scientist Galen (130-201 CE) showed that both the arteries and veins contained blood, something that had not been shown earlier. In the 13th century the scientist Ibn an-Nafis (1205-1288 CE) described the circulation through the lungs, but it was not until the 17th century –when William Harvey wrote his book "De motu cordis"– that the circulatory system was described in more detail, based on truly  scientific studies. In the preface to his book he writes:

"Most Serene King !

The animal´s heart is the basis of its life, its chief member,

the sun of its microcosm; on the heart all its activity depends,

from the heart all its liveliness and strength arises."

 

William Harvey M.D.
Movement of the heart and blood in animals.
An anatomical essay
Frankfurt: William Fitzer, 1928