Galen, a skilled C2nd AD Greek physician and scholar, taught that there were three main inter-connected systems involved in blood flow: a] brain and nerves; b] heart and arteries; and c] liver and veins. Dark, venous blood formed in the liver and then travelled through the veins throughout the body, to deliver nourishment and build tissues. Some blood would come into contact with air in the lungs and go to the heart.
Sometimes the liver produced too much blood, and the body became imbalanced, leading to illness. Blood-letting, drawing off the excess fluid, restored balance.
Galen’s teachings dominated European medicine and scholarship for centuries, mistakes and all. But one of the main Chinese medicine manuals (Yellow Emperor’s Classic of Medicine c300 BC) stated that all blood in the body was pumped by the heart, completed a circle and kept moving! And in the C13th the Arab Dr Ibn an-Nafis suggested blood circulated only from the heart to the lungs and back, without spreading further. Even Italian anatomist Realdo Colombo (1516-59), who examined the beating hearts of animals during vivisections, couldn’t interpret the heart’s function confidently.
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William Harvey (1578-1657) was born in Folkestone, Kent where his father had been a freeholder-farmer. From King's College in Canterbury, the clever young man got a scholarship to Cambridge University.
Then in 1600 he joined other clever C16th English alumni at Padua University, Europe’s best medical school. He did post-grad Medicine under surgeon Girolamo Fabricius, watching his mentor dissect dead criminals and living animals. Fabricius had discovered valves in the veins and concluded that animal blood moved around in a circle continuously, via the pumping heart!
Back home in 1602, Harvey established himself as a physician & married the daughter of Queen Elizabeth's royal physician. In 1607, he took the position of Surgery Lecturer at the Royal College of Physicians and became physician to St Bartholomew's Hospital. In 1618 he became royal physician to King James I (ruled 1603–25) and later Dr Harvey, already a committed royalist, served the next King, Charles I.
Harvey was developing a new theory to explain how blood flowed through the body, based on evidence from his dissections. In the hearts in living animals, Harvey could see that systole was the active phase of the heart's movement, pumping out the blood by its muscular contraction. The action of the heart moved blood out through the arteries to the body, and then back to the heart via veins, dispelling Galen's theories.
Harvey isolated parts of the heart; he ligated and divided arteries and exerted pressure on veins on either side of the valves. He utilised cold-blooded animals because their heartbeats were slow, showing that the heart valves allowed blood to flow in only one direction. Harvey revealed his findings at the College of Physicians in 1616.
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William Harvey published diagram, demonstrating existence of valves in veins.
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An Anatomical Study of the Motion of the Heart and of the Blood in Animals,
written by Dr W Harvey, 1628
Sometimes the liver produced too much blood, and the body became imbalanced, leading to illness. Blood-letting, drawing off the excess fluid, restored balance.
Galen’s teachings dominated European medicine and scholarship for centuries, mistakes and all. But one of the main Chinese medicine manuals (Yellow Emperor’s Classic of Medicine c300 BC) stated that all blood in the body was pumped by the heart, completed a circle and kept moving! And in the C13th the Arab Dr Ibn an-Nafis suggested blood circulated only from the heart to the lungs and back, without spreading further. Even Italian anatomist Realdo Colombo (1516-59), who examined the beating hearts of animals during vivisections, couldn’t interpret the heart’s function confidently.
Dr Harvey showing King Charles I his theory of blood circulation ,
painted by R Hanna, dated ?
So in early C17th Europe, most scientific concepts were still based on ancient philosophy & theology. Were contemporary anatomical studies limited by doctrinal disapproval? Or from fear of heresy charges? The dogmatic College of Physicians still championed Galen’s classicism, even when experimentation became legitimate science.
William Harvey (1578-1657) was born in Folkestone, Kent where his father had been a freeholder-farmer. From King's College in Canterbury, the clever young man got a scholarship to Cambridge University.
Then in 1600 he joined other clever C16th English alumni at Padua University, Europe’s best medical school. He did post-grad Medicine under surgeon Girolamo Fabricius, watching his mentor dissect dead criminals and living animals. Fabricius had discovered valves in the veins and concluded that animal blood moved around in a circle continuously, via the pumping heart!
Back home in 1602, Harvey established himself as a physician & married the daughter of Queen Elizabeth's royal physician. In 1607, he took the position of Surgery Lecturer at the Royal College of Physicians and became physician to St Bartholomew's Hospital. In 1618 he became royal physician to King James I (ruled 1603–25) and later Dr Harvey, already a committed royalist, served the next King, Charles I.
Harvey was developing a new theory to explain how blood flowed through the body, based on evidence from his dissections. In the hearts in living animals, Harvey could see that systole was the active phase of the heart's movement, pumping out the blood by its muscular contraction. The action of the heart moved blood out through the arteries to the body, and then back to the heart via veins, dispelling Galen's theories.
Harvey isolated parts of the heart; he ligated and divided arteries and exerted pressure on veins on either side of the valves. He utilised cold-blooded animals because their heartbeats were slow, showing that the heart valves allowed blood to flow in only one direction. Harvey revealed his findings at the College of Physicians in 1616.
Published in De Motu Cordis, 1628
Was Dr Harvey Protestant, Catholic or rationalist? It has been suggested he was Anglican because although his theories contrasted sharply with the accepted beliefs, Harvey was cautious in his criticisms of traditional values. He was a thinking Renaissance man, not a man of the Science Revolution.
In 1628 Dr Harvey produced a shortish, cheap book in Latin called An Anatomical Study of the Motion of the Heart and of the Blood in Animals, published in Frankfurt. Yet it became one of the most influential books in western science history. And since both Stuart kings had so warmly encouraged Harvey's research, the author was described on the title page as the royal physician.
As with many new ideas, his revolutionary circulation theory was received with interest in Britain. Many proponents agreed with Harvey because of logical experimentation and quantitative methods. Or for religious and philosophical reasons. But there was also controversy among his British colleagues. Some opposed the circulation theory because of their firm commitment to ancient doctrines, the uncertainty of experimentation or because of personal resentments.
In Europe Harvey’s findings were met with some scepticism; while Molière supported Harvey’s views, Descartes and others rejected the idea that the heart pumped the blood. So practising physicians in Europe continued to use traditional remedies based on Galen’s human physiology eg enemas, purgatives, bloodletting.
In 1636 Dr Harvey was sent in a diplomatic mission to Holy Roman emperor, Ferdinand II - a year of travel around Europe, meeting famous professors of medicine, philosophy (eg Thomas Hobbes), literature and art. His connections were impressive. But a great deal of his written work was lost when parliamentary troops ransacked his Whitehall home in 1642.
He followed the king on the Scottish campaigns of 1639-41 and in 1642-6 during the English Civil Wars, in Oxford and Newcastle. Harvey returned to London in 1645 and largely retired from public life, becoming the quiet warden of Merton College, Oxford (1645-6) instead.
In 1649 Harvey published Two Anatomical Exercises on the Circulation of the Blood in response to criticism from French anatomists. On the Motion of the Heart and Blood in Animals came out in English in 1653. He had calculated the total volume of blood that moved through the body in an hour and showed that it was too high for the body to replenish. The amount of blood in the human body HAD to be constant and in perpetual motion.
In 1628 Dr Harvey produced a shortish, cheap book in Latin called An Anatomical Study of the Motion of the Heart and of the Blood in Animals, published in Frankfurt. Yet it became one of the most influential books in western science history. And since both Stuart kings had so warmly encouraged Harvey's research, the author was described on the title page as the royal physician.
As with many new ideas, his revolutionary circulation theory was received with interest in Britain. Many proponents agreed with Harvey because of logical experimentation and quantitative methods. Or for religious and philosophical reasons. But there was also controversy among his British colleagues. Some opposed the circulation theory because of their firm commitment to ancient doctrines, the uncertainty of experimentation or because of personal resentments.
In Europe Harvey’s findings were met with some scepticism; while Molière supported Harvey’s views, Descartes and others rejected the idea that the heart pumped the blood. So practising physicians in Europe continued to use traditional remedies based on Galen’s human physiology eg enemas, purgatives, bloodletting.
In 1636 Dr Harvey was sent in a diplomatic mission to Holy Roman emperor, Ferdinand II - a year of travel around Europe, meeting famous professors of medicine, philosophy (eg Thomas Hobbes), literature and art. His connections were impressive. But a great deal of his written work was lost when parliamentary troops ransacked his Whitehall home in 1642.
He followed the king on the Scottish campaigns of 1639-41 and in 1642-6 during the English Civil Wars, in Oxford and Newcastle. Harvey returned to London in 1645 and largely retired from public life, becoming the quiet warden of Merton College, Oxford (1645-6) instead.
In 1649 Harvey published Two Anatomical Exercises on the Circulation of the Blood in response to criticism from French anatomists. On the Motion of the Heart and Blood in Animals came out in English in 1653. He had calculated the total volume of blood that moved through the body in an hour and showed that it was too high for the body to replenish. The amount of blood in the human body HAD to be constant and in perpetual motion.
written by Dr W Harvey, 1628
published in Latin in Frankfurt.
The Great Fire of London in 1666 engulfed the library that Harvey helped establish at the Royal College of Physicians. His notes on patients, post mortem examinations and animal dissections were lost.
Nonetheless his research continued. Human reproduction was poorly understood, so Harvey investigated the role of sperm and menstrual blood in the formation of the embryo. His observations were excellent, but such matters could not be resolved properly without the use of the microscope (which was invented soon after Harvey’s death).
Eventually the poor doctor suffered from kidney stones. He published his final work, Exercises on the Generation of Animals, n 1651. Harvey attempted suicide but failed and died from stroke at 79 in 1657.
The Great Fire of London in 1666 engulfed the library that Harvey helped establish at the Royal College of Physicians. His notes on patients, post mortem examinations and animal dissections were lost.
Nonetheless his research continued. Human reproduction was poorly understood, so Harvey investigated the role of sperm and menstrual blood in the formation of the embryo. His observations were excellent, but such matters could not be resolved properly without the use of the microscope (which was invented soon after Harvey’s death).
Eventually the poor doctor suffered from kidney stones. He published his final work, Exercises on the Generation of Animals, n 1651. Harvey attempted suicide but failed and died from stroke at 79 in 1657.
Thomas Wright, Circulation: William Harvey's Revolutionary Idea 2013 was very helpful.
Thanks to the guest blogger, Dr Joe.
Thanks to the guest blogger, Dr Joe.