William Harvey

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William Harvey

Harvey William color.jpg
William Harvey
Born

1 April 1578
Folkestone

Died June 3, 1657
Nationality Flag of England English
Field Medicine
Academic advisor  Hieronymus Fabricius
Known for Systemic circulation

William Harvey (April 1, 1578 – June 3, 1657) was an English physician and natural historian who is most well-known for elucidating the circulation of blood. Harvey also made discoveries in areas of comparative anatomy and physiology, pioneering modern embryology and addressing issues of the generation of viviparous and viviparous animals. He has been called the "father of modern physiology," and the "founder of modern experimental physiology" (because his work was based on experiments on animals).

Harvey's groundbreaking work on blood circulation overturned centuries of inaccurate speculation in the Western world. Among his observations were recognizing the continuous flow of blood in the body; the movement of blood from the right to left ventricle through the lungs via the pulmonary artery and pulmonary vein; the role of the left ventricle in pumping blood throughout the entire body; the fact that arteries carried blood always away from the heart; the role of the venous valves in assuring blood in veins always flowed toward the heart; and the correct understanding of the systole and diastole of the heart. He also helped to revive the Muslim tradition of scientific medicine expressed by Ibn al-Nafis.

Contents

Brief biography

Early years

William Harvey was born at home in Folkestone, in the county of Kent in southeast England, on April 1, 1578. His father, Thomas Harvey, was from Folkestone and was a prosperous yeoman (later a Levant Company merchant). His mother, whose maiden name was Joane Halke, was originally of Hastingleigh, Kent. Thomas and Joane Kent also had six other sons, five of whom were important merchants in London and one that was a member of parliament for Hythe.

At the age of ten, William Harvey attended King's School in Canterbury. After six years of grammar school at King's School, at the age of 16, Harvey was awarded a medical scholarship to Gonville and Caius College, Cambridge. This medical scholarship, founded by Matthew Parker, Archbishop of Canterbury, was the first such scholarship in England for which preference was given to Kentish Men (Robb-Smith 1971). Harvey was admitted to Gonville and Caius College on May 31, 1593 (Booth 2001). He received his Bachelor of Arts degree in 1597.

John Caius, who refounded Caius college before Harvey’s time, used to advise his students to seek some part of their medical education abroad: Like him (Copeman 1971), Harvey went on to the celebrated center for European medical instruction, the University of Padua, after spending some time traveling through France and Germany (Booth 2001). The University of Padua had been attended by Copernicus) almost a century before and Galileo was teaching there at the time Harvey was in attendance, but there is no evidence that Galileo and Harvey ever met (Booth 2001). At the University of Padua, Harvey studied under Hieronymus Fabricius of Aquapendente, a great anatomist, and the Aristotelian philosopher Cesare Cremonini. He graduated as a doctor on April 25, 1602.

After graduation, Harvey returned to England and received his Cambridge MD in the same year.

Professional career

In 1602, when he settled in London, Harvey started a medical practice. Two years later, in 1604, he married Elizabeth C. Browne, daughter of Lancelot Browne, a prominent London physician. The couple had no children.

In 1604, Harvey became a candidate for the Royal College of Physicians in London and 1607 he became a Fellow of the College of Physicians (Booth 2001; Giglioni 2004). In 1609, he was formally appointed as assistant physician to St. Bartholomew's Hospital, where he would serve until 1643. In 1613, he became censor in the College of Physicians. In 1615, Harvey became Lumleian Lecturer of Surgery, a position where he would give a series of lectures and also perform an annual public anatomy, with his first lectures delivered in April 1616 (Giglioni 2004; Booth 2001). He gave these lecturers annual at the College for many years (Booth 2001).

In 1618, Harvey became a physician to King James I, the King of England and King of Ireland (and known as King of Scots as James VI). James died in 1625. This began a long link of serving the Royal family. After his and others' attempts to cure James of his fatal illness failed, he became a scapegoat for that failure amidst rumors of a Catholic plot to kill James, but was saved by the personal protection of Charles I (to whom he was also personal physician, from 1625 to 1647). He was appointed physician in ordinary to King Charles I in 1630. As appointed court physician and a member of the royal entourage, he was involved in a number of diplomatic and political activities (Giglioni 2004). In 1629, on the King's orders, he attended the duke of Lennox in his travels abroad and on several occasions (1633, 1639, 1640, 1641), Harvey traveled with the King to Scotland (Giglioni 2004). James took advantage of these royal positions by dissecting deer from the royal parks and demonstrating the pumping of the heart on Viscount Montgomery's son, who had fallen from a horse when he was a boy, leaving a gap in his ribs, subsequently covered by a metal plate, which he was able to remove for Harvey. "I immediately saw a vast hole," Harvey wrote, "and it was possible to feel and see the heart's beating through the scar tissue at the base of the hole" (Williams 2004).

Harvey's groundbreaking work, Exercitatio Anatomica de Motu Cordis det Sanguinis in Animalibus (Anatomical study on the motion of the heart and blood in animals), known as De Motu Cordis, was published in 1628 in Frankfurt (Giglioni 2004). It was this work that Harvey announced his discovery of the circulation of blood in animals. The first English edition would appear in 1653.

Later life

In 1642, Harvey went to Oxford in attendance on King Charles. When his lodgings in London were plundered by Parliamentary troops, during the riots at the start of the First English Civil War, he lost all of his notes on natural history and the generation of insects (Gugliani 2004). Harvey himself went with the king on campaign, and was in charge of the royal children's safety at the Battle of Edgehill, the first pitched battle of the English Civil War, hiding them in a hedge. He was forced by enemy fire to shelter behind the Royalist lines, and at the end of the battle he tended to the dying and wounded.

After traveling with King Charles to Oxford, Harvey stayed there, discontinuing his work with St. Bartholemew's Hospital in 1643, when he took the position of Warden (head of house) of Merton College (Gugliani 2004).

In 1649, Harvey published Exercitationes Anatomicae Duae de Curculatione Sanguinis (Two anatomical exercitations on the circulation of the blood), known in short form as De Circulatione, in which he distanced himself from the explanation of the heartbeat given by Rene Descartes and also defined his idea of spirit as an inherent and material component of the blood (Gugliani 2004).

In 1651, Harvey published Exercitationes de Generatione Animalium (Anatomical exercitations concerning the generation of living creatures), known as De Generatione, in which he examined the issue of the generation of viviparous and oviparous animals and pioneered embryology. Among his presentations was a theory that the parts of higher animals formed successively out of the undifferentiated matter of the egg, a process he called "epigenesis." That is, the embryo does not exist preformed in the egg, but progressively passes through stages, gradually building. Harvey, however, did not understand the process of fertilization of the egg with semen (Gugliani 2004).

In 1651, William Harvey also donated money to Merton College for building and furnishing a library, which was dedicated in 1654. In 1656, he gave an endowment to pay a librarian and to present a yearly oration, which continues to the present day in his honor.

Harvey died of a stroke in 1657, at the age of seventy-nine, and was buried in St. Andrews Church, Hempsted, England. He left money in his will for the founding of a boys' school in his native town of Folkestone; opened in 1674, the Harvey Grammar School has operated continuously up to the present day.

Circulation of the blood

William Harvey was the first in the Western world to describe correctly and in exact detail the systemic circulation and properties of blood being pumped around the body by the heart. The great Muslim scholar Ibn al-Nafis is famous for, among other great accomplishments, being the first physician to describe the pulmonary circulation, and the capillary and coronary circulations, which form the basis of the circulatory system. He is widely considered "the father of circulatory physiology," and some believe the greatest physician in history. Ibn al-Nafis' descriptions of the pulmonary circulation may have been fairly widespread among Muslim physicians in the Islamic world and he is an important forerunner of Harvey. Michael Servetus also had described pulmonary circulation before the time of Harvey, but all but three copies of Servetus' manuscript Christianismi Restitutio were destroyed and as a result, the secrets of circulation were lost until Harvey rediscovered them nearly a century later.

While Ibn al-Nafis had made great breakthroughs in describing pulmonary circulation in the Muslin world in the 13th century, in the Western world in Harvey's time, there were very different views on blood circulation. The prevailing paradigm was the model of Galen back in the second century C.E. This view was that venous (dark red) and arterial (brighter and thinner) blood had different natures, each with distinct and separate functions. Veins and arteries likewise were held as separate systems. The thick venous blood was held to be nutritive and the arterial blood was spiritual and energizing. Venous blood was thought to originate in the liver from assimilation and transformation of food and then ebbed and flowed in the veins to nourish the various parts of the body (Giglioni 2004). Some venus blood was thought to seep through the septum of the heart, which was seen as porous, and after arriving in the left ventricle, mix with air from the lungs (Giglioni 2004). The dominance of this view was a reason that the work of Ibn al-Nafis was ignored in Europe.

Image of veins from Harvey's Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus

Hieronymus Fabricius, Harvey's teacher at Padua, had claimed discovery of "valves" in veins, but had not discovered the true use of them. The explanation that he had put forward did not satisfy Harvey, and thus it became Harvey's endeavor to explain the true use of these valves, and eventually, the search suggested to him the larger question of the explanation of the motion of blood. Harvey announced his discovery of the circulatory system in 1616 and in 1628 published his work De Motu Cordis, where, based on scientific methodology, he argued for the idea that blood was pumped around the body by the heart before returning to the heart and being re-circulated in a closed system.

Harvey based most of his conclusions on careful observations recorded during vivisections made of various animals during controlled experiments, being the first person to study biology quantitatively. He did an experiment to see how much blood would pass through the heart each day. In this experiment, he used estimates of the capacity of the heart, how much blood is expelled each pump of the heart, and the amount of times the heart beats in a half an hour. All of these estimates were purposefully low, so that people could see the vast amount of blood Galen's theory required the liver to produce. He estimated that the capacity of the heart was 1.5 ounces, and that every time the heart pumps, 1/8 of that blood is expelled. This led to Harvey's estimate that about 1/6 of an ounce of blood went through the heart every time it pumped. The next estimate he used was that the heart beats 1000 times every half an hour, which gave 10 pounds 6 ounces of blood in a half an hour, and when this number was multiplied by 48 half hours in a day, he realized that the liver would have to produce 540 pounds of blood in a day. At this time, common thought was that the blood was produced and not constantly recycled.

Harvey proposed that blood flowed through the heart in two separate closed loops. One loop, pulmonary circulation, connected the circulatory system to the lungs. The second loop, systemic circulation, causes blood to flow to the vital organs and body tissue.

Harvey also observed that blood in veins would move readily towards the heart, but veins would not allow flow in the opposite direction. This was observed by another simple experiment. Harvey tied a tight ligature onto the upper arm of a person. This would cut off bloodflow from the arteries and the veins. When this was done, the arm below the ligature was cool and pale, while above the ligature it was warm and swollen. The ligature was loosened slightly, which allowed blood from the arteries to come into the arm, since arteries are deeper in the flesh than the veins. When this was done, the opposite effect was seen in the lower arm. It was now warm and swollen. The veins were also more visible, since now they were full of blood. Harvey then noticed little bumps in the veins, which he realized were the valves of the veins, discovered by his teacher, Hieronymus Fabricius. Harvey tried to push blood in the vein down the arm, but to no avail. When he tried to push it up the arm, it moved quite easily. The same effect was seen in other veins of the body, except the veins in the neck. Those veins were different from the others—they did not allow blood to flow up, but only down. This led Harvey to believe that the veins allowed blood to flow to the heart, and the valves maintained the one way flow.

Harvey further concluded that the heart acted like a pump that forced blood to move throughout the body instead of the prevailing theory of his day that blood flow was caused by a sucking action of the heart and liver. These important theories of Harvey represent significant contributions to the understanding of the mechanisms of circulation.

Legacy

Harvey's ideas were eventually accepted during his lifetime. It did confront the prevailing paradigm of Galen, which dominated thought of the time, and was of significant importance in overcoming that pernicious influence. Harvey's work was attacked, notably by Jean Riolan in Opuscula anatomica (1649), which forced Harvey to defend himself in Exercitatio anatomica de circulations sanguinis (also 1649) where he argued that Riolan's position was contrary to all observational evidence. Harvey was still regarded as an excellent doctor.

Robert Fludd, a colleage at the College of Physicians was the first to accept Harvey's circulatory model, and Rene Descartes also accepted the discovery of the circulation of the blood but disagreed with Harvey's explanation for the movement of the heart (Giglioni 2004). Leyden University (Leiden University) was the first to accept Harvey's views on the continent, but in many schools it was a further half century before his work was fully appreciated (Booth 2001). Marcello Malpighi later proved that Harvey's ideas on anatomical structure were correct; Harvey had been unable to distinguish the capillary network and so could only theorize on how the transfer of blood from artery to vein occurred.

By the beginning of the eighteenth century, Hermann Boerhaave, the great Dutch teacher of medicine in Leyden, stated that nothing written before Harvey was any longer worthy of consideration (Booth 2001).

Even so, Harvey's work had little effect on general medical practice at his time—blood letting, based on the prevailing Galenic tradition, was a popular practice, and continued to be so even after Harvey's ideas were accepted. Harvey's work did much to encourage others to investigate the questions raised by his research, and to revive the Muslim tradition of scientific medicine expressed by Nafis, Ibn Sina (Avicenna), and Rhazes.

Pulitzer Prize-winning historian Arthur Schlesinger Jr. included William Harvey in a list of "The Ten Most Influential People of the Second Millennium" in the World Almanac & Book of Facts (Schlesinger 2000).

Further reading

  • Butterfield, H. 1957. The Origins of Modern Science. New York: The Free Press.
  • Gregory, A. 2001. Harvey's Heart, The Discovery of Blood Circulation. Cambridge, England: Icon Books. ISBN 1840462485.
  • Harvey, W. 1889. On the Motion of the Heart and Blood in Animals. London: George Bell and Sons.
  • Kearney, H. 1971. Science and Change 1500-1700. New York: McGraw-Hill. OCLC 139944.
  • Mitchell, S. W. 1907. Some Memoranda in Regard to William Harvey, M.D.. New York.
  • Rapson, H. 1982. The Circulation of the Blood. London: Frederick Muller. ISBN 0584110138.
  • Royal Society of Medicine (Great Britain). 1913. Portraits of Dr. William Harvey. London: Humphrey Milford, Oxford University Press.
  • Singer, C. 1959. A History of Biology. London: Abelard-Schuman.

References

  • Booth, C. C. 2001. In C. Blakemore, and S. Jennett. 2001. The Oxford Companion to the Body. New York: Oxford University Press. ISBN 019852403X.
  • Copeman, W. S. C. 1971. In A. Rook (ed.), Cambridge and its Contribution to Medicine. London: Wellcome Institute of the History of Medicine. OCLC 67607521.
  • Giglioni, G. 2004. William Harvey. In J. Dewald, Europe, 1450 to 1789: Encyclopedia of the Early Modern World. Thomson/Gale. ISBN 0684314231.
  • Robb-Smith, A. H. T.. 1971. Medical education in Cambridge before 1600. In A. Rook, (ed.), Cambridge and its Contribution to Medicine. London: Wellcome Institute of the History of Medicine. OCLC 67607521.
  • Schlesinger, A. 2000. World Almanac's ten most influential people of the Second Millennium. World Almanac 2000. Retrieved January 28, 2009.
  • Williams, N. 2004. History of biology: On brain and soul. Current Biology 14:454.

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