2.3 William Harvey

• When was William Harvey born? Where did he study medicine? When and where did he become a lecturer of anatomy? When did he become one of the royal doctors of James I?

  William Harvey was born in 1578. He studied medicine at Cambridge, and then at the famous medical school in Padua. In 1615, he became a lecturer of anatomy at the College of Physicians, and by 1618 he was one of the royal doctors for James I.
• What did Harvey have a keen interest in? What was part of his job? What did he teach his students? Who later worked on this theory?

  Harvey had a keen interest in dissection and observing the human body, in order to improve his knowledge of human anatomy. Carrying out public dissections was part of his job. He taught his students that it was important to observe the body and believe what they saw, rather than believing what had been written in classical texts. This idea was also followed by Thomas Sydenham, who would work on this theory later that century.
• What was Harvey particularly interested in? What was he taught in Padua? How did Harvey prove this theory? What did this prove?

  Harvey was particularly interested in blood. During his studies at Padua, his professors had taught him Vesalius's theory that the veins of the body contained valves, which was proof that the blood in those veins flowed towards the heart. Using dissected bodies, Harvey saw the evidence to prove this theory. When he tried to pump liquids through the veins the other way, it did not work. This proved that the blood only flowed towards the heart, contradicting what Galen had taught about the blood.
• What did Harvey look into more detail? What did Harvey work out?

  Harvey looked in more detail at the old Galenic theory. It stated that blood was made in the liver as a product of what a person ate, then flowed through the body to provide energy and was burned up. Harvey worked out that if Galen's theory was correct, the liver would have to make 1,800 litres of blood a day for a person to survive!
• What was Harvey influenced by?

  Harvey was influenced by new inventions that had appeared during the Renaissance. Fire engines now used mechanical pumps to provide water to put out fires: perhaps the human body worked in the same way.
• What did Harvey's research involve? What did he famously prove?

  Harvey's research involved dissecting human corpses and cutting open cold-blooded animals, which had a much slower heartbeat, to observe the movement of their blood while they were still alive. Through his research, he famously proved that arteries and veins were linked together into one system.
• How did Harvey prove that arteries and veins were linked together into one system?

  This was done by tying a tight cord around somebody's arm and cutting off the blood flow in the artery leading into the arm. Because the artery in the arm is deeper than the veins, loosening the cord a little bit allowed blood to flow into the arm but stopped it from flowing out and the veins swelled with blood.
• What was Harvey's theory about blood circulation? What do we know about today to prove this?

  Harvey's theory was that blood must pass from arteries to veins through tiny passages that were invisible to the naked eye. Today we know about these blood vessels- they are called capillaries.
• What did Galen suggest about the flow of blood inside the heart? And the veins and arteries? How did Harvey prove these ideas wrong?

  Galen had suggested that blood flowed from one side of the heart to the other through invisible pores in the walls of the ventricles. He also said that veins carried both blood and pneuma*, which was picked up in the lungs, while arteries carried just blood. Harvey's theory criticised both of these ideas. He showed that the veins carried only blood. He proved that the heart acted as a pump just as the new mechanical fire pumps did.
• What were the factors enabling Harvey's discoveries?

  1. Individuals and Institutions

  2. Science and technology

  3. Attitudes in society - the 'Medical Renaissance
• Individuals and institutions:

  
  

  What was William Harvey employed as? How did this help him?

  How did the decline of the power of the Church help Harvey?

  Harvey's own abilities and the Government (King Charles I)- Individuals such as Vesalius had previously proved parts of the work of Galen wrong, which made it easier for other scientists and physicians to do the same.

  
  

  
  

  Harvey was employed by Charles I as his personal physician. This gave him credibility, in the same way the royal charter gave credibility to the Royal Society. More people heard of Harvey's theory about the circulation of blood.

  
  

  The decline of the power of the Church also enabled Harvey to be critical of Galen's teachings.
• Science and Technology

  eg. dissections becoming more commonplace, mechanical firefighter pumps - Newly popular technologies, like the pump used when fighting fires, inspired Harvey to look again at how the heart worked.
• Attitudes in Society- 'The Medical Renaissance'

  There was more interest in science and in solving some of the puzzles of the human body. People had begun to search for rational explanations for things.
• What did Harvey's arguments rely on? What is his book? And what is it considered to be?

  Whose teachings did Harvey follow as he did not believe Galen? What did he believe?

  Harvey’s arguments relied on careful observations of human and animal anatomy. Many people consider his book,An Anatomical Account of the Motion of the Heart and Blood in Animals,to be the beginning of modern physiology.

  However, Harvey did not consider himself to be a ‘modern’ scientist. He didn’t believe many of Galen’s theories, but he did follow the teachings of another classical thinker: Aristotle. Like Aristotle, he believed that the body was designed by a higher power, and thought that the soul was responsible for how the body worked.
• What was the most immediate impact of Harvey's theory of blood circulation?

  Give an example of this.

  The most immediate impact that Harvey's theory had was to encourage other scientists to experiment on actual bodies. For example, Harvey had proved that the liver did not digest food to create blood. If the liver didn't make blood, what did it do? Harvey had proved that blood circulated, instead of being absorbed to provide nourishment for the body- how, then, was the body nourished?
• How useful was Harvey's theory in medical treatment?

  What did Harvey manage to do?

  Why did some doctors criticise Harvey? What did they reason?

  When did English medical textbooks continue giving Galen's account until?When did Harvey's ideas appear?


  However, understanding the circulation of the blood had little practical use in medical treatment. This meant that the impact of Harvey's discoveries on treatment during the 17th century was quite limited.

  
  

  He may have paved the way for a modern understanding of anatomy and how the human body functions, but a lot of doctors at the time ignored him. Some even openly criticised him. Nobody liked to be told that they had been doing their job incorrectly. They also reasoned that nobody recovered from disease by simply knowing that the blood flowed to the heart. To many, it had no practical application.

  
  

  English medical textbooks continued to give Galen's account until 1651; Harvey's ideas only began to appear in universities from 1673.