Harvey

• In 1628, Wiliam Harvey, an English physician, published the book ‘An Anatomical Disputation concerning the Movement of the Heart and Blood in Living Creatures’.
• The book described accurately for the first time how blood was pumped around the body by the heart. It disproved Galen’s ideas regarding blood.
• Galen stated that new blood was replaced after it was burnt up. Secondly, he suggested that there were invisible holes in the septum of the heart.
• William Harvey studied medicine in Cambridge, England and Padua, Italy.
• Harvey became a doctor in London and later served the King of England, Charles I.
• Harvey noticed that the valves in the veins only allowed blood to flow towards the heart and vice versa with the arteries.
• Harvey then went on to calculate the amount of blood travelling around the human blood in an hour. Harvey realised that there was too much blood for it to be constantly reproduced and concluded that the same blood must be pumped around the body several times an hour.
• Harvey suggested that blood must be taken away from the heart along the arteries and back to the heart through veins. However, this discovery was not immediately accepted as it contradicted Galen's work.
• Harvey was also unable to explain how the blood moved from the arteries to the veins. It wasn’t until the development of the microscope that capillaries were discovered.
• Marcello Malpighi, using one of the earliest effective microscopes, was able to explain how blood moved from the arteries to the veins.