The Life Of William Harvey

William Harvey an English physician, was the first ever to describe the circulation of our body and properties of blood being transported throughout your body by its 'mechanical pump', the heart.

He studied medicine at the University of Padua in Italy and was tutored by surgeon Hieronymus Fabricius. Fabricius, was fascinated with anatomy, and found out that the veins in the body had one-way valves, but had not been too sure in regards to what their function was. Harvey continued, based on Fabricius's findings, to determine the role valves play in circulation of the body.

He returned from Italy in 1602 and established himself as a physician. His career was taken to a complete new, better level when he married Elizabeth Browne, the daughter of Elizabeth I's physician. They were married in 1604. He became a fellow of the Royal College of Physicians in 1607 and, in 1609, was appointed physician to St Bartholomew's Hospital. The highlight of his career, however was probably when he became physician to Elizabeth's successor James I also to James' son Charles when he ascended to the throne, in 1618. Both King James and King Charles took a close affinity for and encouraged Harvey in every step of his research.

Harvey's research was furthered through the dissection of animals. He first revealed his theories at the faculty of Physicians in 1616. In 1628 he published these theories in a book titled 'Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus' ('An Anatomical Study of the Motion of the Heart and of the Blood in Animals'). Here was where he explained the way the heart pumped the blood in a circular course through your body. His discovery received great accolades and involvement in England, although it was greeted with some scepticism on the Continent.

Harvey was also the first to theorize that humans and other mammals reproduced via the fertilisation of egg by sperm. It took another two centuries before a mammalian egg was finally observed, but Harvey's theory still won credibility during his lifetime.

Harvey held an in depth relationship with the royal family through the English Civil War and also witnessed the Battle of Edgehill.

Harvey is often credited as the daddy of Cardiovascular Medicine. His observations of dissected hearts showed that the valves in the heart allowed blood to flow in mere one direction. Also, even though he lacked a microscope, he theorized that the arteries and veins were linked to the other person by capillaries, which were later be learned by Marcello Malpighi some years after Harvey's death.

William Harvey's work became the foundation for those modern research on the heart and cardiovascular medicine. It's been said that Harvey's proof "of the continuous circulation of the blood within a contained system was the seventeenth century's most significant achievement in physiology and medicine. "

He is also often referred to as the Father of Scientific Method. Harvey believed that direct observation was the way in which to draw conclusions about scientific facts. He kept records of his experiments. He didn't record his findings until he proved them. This practice became known as the scientific method, and Harvey has received much credit for having promoted its use.

Historical background

William Harvey was the eldest child of merchant Thomas Harvey and Joan Halke and was born in Folkestone, Kent on the very first of April, 1578. His father was known to be a styled gentleman, who after discussing the register of William's matriculation at Cambridge, was designated a yeoman of Kent. He will need to have been a man of some substance and position, as most of his seven sons followed careers, and attained positions necessitating the possession of capital at the outset. William had five brothers who were all merchants of repute in the town of London. They traded extensively with Turkey and the Levant. John, the second son, was at one time Member of Parliament for Hythe, and afterwards became King's Beceiver for Lincolnshire, and Footman to His Majesty. Of Joan Halke, Harvey's mother, but little has been preserved to us, and that little has been produced from the inscription on the monumental slab in Folkestone Church. She actually is there referred to as having died in her 50th year, the mother of seven sons and two daughters. " A Godly harmles Woman: A chaste loveing Wife: A charitable quiet Neighbour: A co'fortable frendly Matron: A p'evident diligent Huswyfe: A careful te'der-harted Mother. Deere to her Husband: Eeverensed of her Children: Beloved of her Neighbours: Elected of God. Whose Soule Best in Heaven: her Body in this Grave: To Her a Happy Advantage: To Hers an Unhappy Loss. " Conjecture has attributed the authorship of the inscription to her son William. There were two daughters, one of whom died young, and of the other nothing beyond her name is known. Harvey attended King's School in Canterbury from 1588 to 1593. There he worked at the normal subjects of an English education, and acquired a good knowledge of both Latin and Greek. This is essential at a time when the influence of authority was triumphant, and when even modern-day literature, to appear learned, must needs be expressed in Latin. He then studied at Cambridge University and Gonville and Caius College from 1593 to 1599. He spent these years in the analysis of classics, dialectics and physics. Such a course of training was then, as now, considered a fitting prelude to the study of the science and art of medicine. In 1597, being then nineteen years, he was made a Bachelor of Arts of his university. In those days, and indeed until quite recently, the University of Cambridge was in a very different position in regards to to the teaching of medicine from what we have now find. Divinity was its chief glory, and the well equipped medical school of today's was almost unrepresented, a couple of professorships only being devoted to medical subjects. Hence he decided to attend one of the premier institutes of Medicine in the Continent, located in Padua, to pursue his career in medicine. It had been there that he worked with Hieronymus Fabricius, who was a favorite anatomist and had observed the one-way valves in blood vessels. After graduating from Padua, he returned to England to establish himself as your physician and joined the faculty of Physicians on the 5th of October, 1604. After marrying Elizabeth Browne, daughter of physician Lancelot Browne, he accepted his position at St. Bartholomew's Hospital, succeeding a Dr. Wilkinson, as the physician in charge of the hospital. At this point, the physician's function consisted of a simple but thorough analysis of patients who have been brought to the hospital once a week and the consequent writing of prescriptions.

- Hieronymus Fabricius

The next important phase of Harvey's life commenced when he was appointed to the office of Lumleian lecturer on 4 August 1615. The Lumleian lectureship, consisted in giving lectures for an interval of seven years, with the goal of enlightening and increasing the general knowledge of anatomy throughout England. Harvey started his lectures in April 1616. At the moment, at age thirty-seven, he was referred to as "a guy of lowest stature, round faced; his eyes small, round, very black and full of spirit; his hair as black as a raven and curling" ( Book : William Harvey; author : Sir D'Arcy Power; year: 1897). A number of the notes which he used at that time are preserved in the British Museum (the manuscript notes which contain the first account of blood circulation). At the beginning of his lectures, Harvey laid down the canons for his guidance:

"To show approximately may be instantly, the whole belly for instance, and afterwards to subdivide the parts according with their positions and relations.

To explain what's peculiar to the actual body which is being dissected.

To supply only by speech what can't be shown on your own credit and by authority.

To break up approximately may be in the sight of the audience.

To enforce the right thoughts and opinions by remarks drawn far and near, and illustrate man by the structure of animals.

Not to praise or dispraise other anatomists, for all did well, and there was some excuse even for those who are in error.

Not to dispute with others, or attempt to confute them, except by the most obvious retort.

To state things briefly and plainly, yet not letting anything pass unmentioned which can be seen.

Not to talk about anything that can be well explained without your body or can be read at home.

Not to enter too much detail, or in too minute dissection, for enough time will not permit.

To allot an absolute time to each part of the body i. e. first day's lectures focused on the abdomen, the next to the thorax, the 3rd to the brain and so on. " (Book: William Harvey; author: Sir D'Arcy Power; year: 1897).

He soon attained a practice of great importance, when he was appointed the "Physician Extraordinary" to King James I, on another of February 1618. Although Harvey's practice suffered because of his radical views, he was also in the picture during King Charles I's reign. Harvey accompanied King Charles I wherever he went as 'Physician in Ordinary. ' Specifically, Charles' hunting expeditions gave Harvey usage of many deer carcasses. Harvey made use of these deer carcasses by conducting the majority of his experiments about them; from these, he made his many observations and consequent theories.

- King James I

- King Charles I

During the English Civil War a mob of citizen-soldiers up against the King entered Harvey's lodgings, stole his goods, and scattered his papers. The papers contains the records of a big quantity of dissections. . . of diseased bodies, with this observations on the development on insects, and a series of notes on comparative anatomy. ( Book: William Harvey; author: Sir D'Arcy Power; year: 1897). Harvey continued to keep up his position and helped the wounded on several occasions. He also protected the King's children.

The conflicts of the Civil War soon led King Charles to Oxford, with Harvey attending, where in fact the physician was made 'Doctor of Physic' in 1642 and later Warden of Merton College in 1645. "In Oxford he (Harvey) very soon settled down to his accustomed pursuits, unmindful of the clatter of arms and of the frequent marching and countermarching around him, for the town remained the base of businesses until its surrender. . . " ( Book: William Harvey; author: Sir D'Arcy Power; year: 1897)

- Merton College

The surrender of Oxford in 1645 marked the beginning of Harvey's gradual retirement from the medical world. Now sixty-eight yrs. old and childless, Harvey had lost three brothers and wife at this time. He made a decision to go back to London and live with his brothers Eliab and Daniel separately and in several intervals. Having retired from St BartholomewHYPERLINK "http://en. wikipedia. org/wiki/St_Bartholomew's_Hospital"'HYPERLINK "http://en. wikipedia. org/wiki/St_Bartholomew's_Hospital"s Hospital and his various other aforementioned positions, he passed the majority of this time reading general literature. Several attempts to bring Harvey back into the 'working world' were made, however; here is an excerpt of one of Harvey's answers:

"Might you be the person who should recommend me to give up the peaceful haven where I now pass my life and launch again after the faithless sea? You know full well just what a storm my former lucubrations raised. Much better could it be oftentimes to grow wise at home and in private, than by publishing what you have amassed with infinite labour, to stir up tempests that may rob you of tranquility for the rest of your days. " (Book: William Harvey; author: Sir D'Arcy Power; year :1897)

He died of any stroke on June 3, 1657, and, "lapt in lead, " was buried in Hempstead church. Apparently, he died of the cerebral hemorrhage from vessels long injured by gout: it is highly probable that the left Sylvian artery malfunctioned, resulting in a gradual accumulation of blood to the brain which eventually overwhelmed it, leading to his death. There is a fairly detailed account of what happened on that day; based on the information accessible, Harvey:

". . . visited speak and discovered that he had the dead palsy in his tongue; then he saw what was to become of him. He knew there were then no hopes of his recovery, so presently he sends for his young nephews to appear to him. Then made signs (for seized with the dead palsy in his tongue he could not speak) to let him blood his tongue, which did him little or no good, therefore ended his days, dying in the evening of the day on which he was stricken, the palsy giving him an easy passport. " (Book: William Harvey; author: Sir D'Arcy Power; year: 1897)

Experimental Procedures

Harvey was well been trained in anatomy, and he, like his idols Versalius and Fabricius, was convinced that the interventricular septum had not been leaky to blood. Also, he was created into a time where experimentation, computation and simple observation, became named essential tools of the "scientific method. " He was well aware of the works of Copernicus and Kepler, and of his modern day Galileo, for whom the combination of careful observation and computation resulted in nothing less than a switch between the earth and the sun as the guts of our own universe; Galileo's dictum "Measure all that is measurable, and make those things measurable which have hitherto not been measured" (Book: William Harvey's Biological Ideas; author: W. Pagel; year: 1967) was deeply impressed upon him. He was also acquainted with the somewhat earlier writings of Santorio Santoro, who, sitting down on an exquisitely sensitive balance, compared his bodyweight and the difference between your ingested food and his excreta and was with the capacity of observing that your body lost a degree of weight continuously by means of "insensible perspiration" (Book: History of Physiology; author: E. Rothschuh; year: 1973).

But Harvey himself was a pioneer (Book: Handbook of Physiology: Circulation; author: CD Leake; year: 1962 ). Unlike the great Kepler, who improved upon Copernicus' observations, and Galileo, whose telescope unequivocally established the Copernican revolution, Harvey did not build on anything, revise anything, or improve on anything.

This revolution was set forth in his publication entitled "Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus" or "Anatomical Essay on the Motion of the Heart and Blood in Animals" (Book: In the Motion of the Heart and Blood in Animals; author: William Harvey, translated by Keynes G; year: 1978), commonly referred to as "De Motu Cordis" or simply "De Motu. " It was published in 1628 when Harvey was already 50 years old.

Knowing that he was challenging a "big fish", he opened the monograph with a letter to the King, Prince Charles, with the statement :

The heart of animals is the building blocks of their life, the sovereign of everything within them. . . from which all power proceeds. The King, in like manner, is the foundation of his kingdom, sunlight of the world around him, the heart of the republic, the foundation whence all power, all grace doth flow. (Book: Scientific Papers: Physiology, Medicine, Surgery, Geology, with Introductions, Notes and Illustrations; author: William Harvey, translated by Willis R; year: 1910)

His dedication to the President of the Royal College of Physicians reads like: "Hey, I'm really not out to get anyone, all I want to do is tell the reality!" For instance, in this "dedication" he states

. . . the studious and good and true do not esteem it discreditable to desert error, though sanctioned by the best antiquity, for they know full well that to err, to be deceived, is human. . . . I'd not charge with willful falsehood anyone who was simply sincerely anxious for truth, nor lay it at any one's door as a crime that he had fallen into error. I avow myself the partisan of truth alone. . . . (Book: Scientific Papers: Physiology, Medicine, Surgery, Geology, with Introductions, Notes and Illustrations; author: William Harvey, translated by Willis R; year: 1910)

He closes: "Farewell, most worthy Doctors, and think kindly of your Anatomist" (Book: Scientific Papers: Physiology, Medicine, Surgery, Geology, with Introductions, Notes and Illustrations; author: William Harvey, translated by Willis R; year: 1910), suggesting that he feared the worst.

Harvey's revolutionary conclusion that blood is conserved and circulates was predicated on only a few observations, the major ones were the following:

First, he measured the quantity of blood that may be drained from sheep, pigs, plus some other subprimate mammals.

He then measured the quantity of the left ventricles of the animals and calculated that, if the left ventricle were to empty with each beat, in a single hour the full total volume of blood pumped would be much greater that in the ingesta( material taken in to the body by means of the digestive system) or even that within the whole animal. Indeed, this might be true even if one-tenth of the blood contained by the ventricle were ejected per beat. Therefore, he concluded, ". . . it is just a matter of necessity that the blood execute a circuit, that this returns to whence it lay out. "

He then demonstrated, publicly, that when a live snake is "laid open, " compression of the vein entering the heart leads to a small heart that is devoid of blood after opening it.

If on the contrary, the artery rather than the vein be compressed or tied you will observe the part between the obstacle and the heart, and the heart itself to be largely distended and, in the long run, to be so oppressed with blood that you'll believe it about to be choked. (Book: Scientific Papers: Physiology, Medicine, Surgery, Geology, with Introductions, Notes and Illustrations; author: William Harvey, translated by Willis R; year: 1910)

He also showed that, following light application of a tourniquet to the arm, the veins become engorged and that blood can only be milked from an engorged vein in the oral direction - toward the heart - but when the vein is thus emptied it only fills from the periphery. Also, when one knows the diameter and amount of the cylinder of vein, one can calculate the volume of blood that flows through the vein during rapid emptying and refilling. Harvey showed that in a day more blood flows during that segment alone than the amount of food ingested.

Harvey's experiment illustrating the venous valves (nodes or portals) and the unidirectional nature of emptying and filling. He also states: "Now if you reckon the business enterprise, how much by one compression moves upwards by suppression of the portal, and multiplying that by thousands, you shall find very much blood pass'd by this means through a little part of any vein, that might be yourself correctly persuaded regarding the circulation of the blood, and of its swift motion" (Book: Scientific Papers: Physiology, Medicine, Surgery, Geology, with Introductions, Notes and Illustrations; author: William Harvey, translated by Willis R; year: 1910).

Harvey also possessed a lifelong obsession with animal generation. His fascination with the perfection of animals caused his desire to find out the way the organisms arise. This is described in his introduction to his Essays on the Generation of Animals. His fascination sprouted from his study of Aristotle's ideas of generation. Harvey made a decision to further investigate Aristotle's views by studying a hen's eggs in order to understand this is of generation in animals. He justified his decision and his plan of pursuing his research in "Of the technique to be pursued in studying Generation" passage of the introduction to Essays of the Generation of Animals. To begin with, a hen's egg had a simple structure and readily available for frequent experimentation. Inside the introduction to his essays, he further explained that his selection of using a chicken egg was acceptable because the other animals had similar means of generation. Results drawn from the experiment he would conduct on a hen's egg could be related to the reproduction in more complex animals; even animals that did not produce eggs. All animals reproduce with some form of an egg, which he considered to be a metaphor for the easy origin of any new life form. Harvey considered it necessary to begin with the simpler animals because this would allow him to repeat the tests many number of that time period to ensure accurate results. His strategy was to see the forming of a chick to create a history of its development. Harvey would then use this information showing the reason for generation and the order in which it proceeded in.

 

Before Harvey's research, scientists believed in a theory known as pre-formation, which assumed an animal already possessed the traits of the mature mammal and grew in proportions in the mother's womb. William Harvey refuted these prior theories in his consideration of the annals of egg's development. He noticed that the fetus started out as an individual drop of blood and then further differentiated into an egg which later became the chick. Because of this, he rejected the idea an exact replica of the organism could be found in reproductive material of either the male or the female. Harvey, however, learned by investigating the stages of development in the eggs that some parts of the pet are engendered before others. (Book: William Harvey and the goal of Circulation; author: Walter Pagel; year: 1951).

 

Another concern of Harvey's was the theories of previous scientists on the role of the male and the female in animal generation. Scientists before attemptedto find an answer to this mystery. Galen assumed the yolk in a hen's egg was a joint of male and female secretions (Book: Investigations into Generation; author: Elizabeth Gasking; year: 1967). Aristotle hypothesized that the cause of generation was the male's semen acting on the menstrual blood of the feminine making the menstrual blood the foundation of matter and the semen the efficient source (Book: William Harvey and the Primacy of Blood; author: John White; year: 1986). Fabricius presumed the male caused the material and the female provided the nourishment.

Harvey wished to solve the mystery of the goal of each sex, so he examined the male and female genital systems of the deer carcasses he within King Charles' Royal Parks (Book: Investigations into Generation; author: Elizabeth Gasking; year: 1967). Through Harvey's investigation, he disproved Aristotle's theories and clarified this in the passage "Of the way in which, according to Aristotle, when a perfect and fruitful egg is made by the male and female fowl" in his essays (Book: The Works Of William Harvey; translated by Robert Willis; year: 1847). He did not consider Aristotle's 'efficient cause' as relevant in the discussion of reproduction because Aristotle's agent of the efficiency was only semen from the male. According to Harvey, semen was an external cause and may not produce an impact on the soul of the offspring because it had not been with it throughout its lifetime of the offspring (Book: Investigations into Generation; author: Elizabeth Gasking; year: 1967). Also, Harvey explained the female must have a role in the efficiency when he stated, "The earth, too, spontaneously engenders a lot of things without seed, and among animals, certain females, but females only, procreate of themselves and without the concurrence of the male: hens, for example, lay hypenemic eggs; but males; with no intervention of females, engender nothing" (Book: The Works Of William Harvey; translated by Robert Willis; year: 1847). He deduced that if the female can reproduce minus the male, then the male should not be the only agent to create the efficiency. He was able to develop this view by looking at less complex organisms and extending it to more evolved animals because he considered all animals to share similar reproductive processes. Accordingly, he allowed himself to make broad generalizations about generation through species barriers. One of the multiple reasons for William Harvey's success was his meticulous experimentation, now known as the scientific method. Scientists preceding William Harvey used experimentation in order to investigate; however, Harvey set a fresh standard for testing. He made precise calculations before and during experiments. For instance, in his study of circulation, he calculated the exact amount of blood released from the heart with every thrust (Book: Early Reactions to Harvey's Circulation Theory: The Impact on Medicine; author: Steven Lubitz; year: 2004). Harvey closely examined and dissected various animals. While many scientists such as Galen used only careless observation, Harvey tested physically and then retested numerous times to ensure his results lacked error. In fact, William Harvey was the first ever to apply quantitative and observational methods simultaneously within his research. He picked test subjects that might be immediately available for many experiments. In the examination of blood and animal generation, Harvey used hen's eggs because these were cheap and available by the bucket load. As the King's physician, Harvey examined deer in his studies of animal generation. King Charles was fascinated with Harvey's research, so he gave the carcasses of his weekly deer hunting to Harvey to dissect (Book: Where Do Babies RESULT FROM? ; author: R. V. Short; year: 2000). The substitution of the mammal into testing greatly advanced Harvey's research because he could relate his concepts of reproduction to an organism that didn't produce an actual egg.

Contributions

Harvey was awestruck by the way blood flowed through our body. Most people of the day believed that food was changed into blood by the liver, and then was consumed as fuel by your body. Harvey knew this is false by the knowledge of his firsthand observations of the human and animal dissections he made earlier to review on. In 1628 Harvey published An Anatomical Study of the Motion of the Heart and of the Blood in Animals which explained how blood was pumped from the heart throughout the body, then returned to the heart and re-circulated. This book expressed views which were very controversial and lost Harvey many patients, but it finally became the basis for those modern research on the heart and blood vessels. Unlike the other anatomical textbooks written before, Harvey's book has only one illustration with a couple of four related figures. This lack of pictures was probably deliberate to show Harvey's dedication to the scientific experimental method. The reader by actually recreating Harvey's experiments was forced to follow each step of Harvey's methods specifically, in a way that a general study of illustrations didn't require. The four figures depict a straightforward but persuasive experiment that can be performed on the human arm without dissection. The experiment involves tying the arm with a tourniquet and adjusting the tightness to show that the blood can either be take off from the arm or permitted to overfill the arm, leading to the veins to bulge. This procedure was also used for bloodletting: removing blood from the vein in the arm was a common treatment for a variety of medical ailments and was also a means of stopping disease.

Bloodletting was a common therapy of early medicine. It was done by cutting into a vein, called venesection or phlebotomy. This work was often done by a surgeon or a barber-surgeon. The veins near the elbow were commonly used.

In this book, Harvey proves the following:

that it's the contraction, not the dilation, of the heart which coincides with the pulse, and that the ventricles as true muscular sacs squeeze the blood which they contain into the aorta and pulmonary artery;

that the pulse is not made by the arteries enlarging and so filling, but by the arteries being filled up with blood and so enlarging;

that there are no pores in the septum of the heart, so the whole blood in the right ventricle is delivered to the lungs and around by the pulmonary veins to the left ventricle, and also that the complete blood in the left ventricle is again sent in to the arteries, around by small veins in to the vena cava, and by them to the right ventricle again -- thus making a complete "circulation";

that the blood in the arteries which in the veins is the same blood;

that the action of the right and left sides of the heart, auricles, ventricles and valves, is the same, the mechanism in both being for reception and propulsion of liquid and not of air, since the blood on the right side, though mixed with air, continues to be blood;

that the blood sent through the arteries to the tissues is not absolutely all used, but that most of it runs through into the veins;

that there is absolutely no to and fro undulation in the veins, but a constant stream from the distant parts towards the heart;

that the dynamical starting-point of the blood is the heart rather than the liver.

This demonstration of the circulation was incomplete in a single point only, though. Harvey cannot uncover the capillaries through which the blood passes from the arteries into the veins. This gap in the circulation was filled in several years later by the great Italian anatomist Marcello Malpighi, who in 1661, a couple of years after Harvey's death, observed in the lungs of any frog, by the newly invented microscope, the way the blood passes from the main one group of vessels to the other. Harvey saw all that could be seen by the naked eye in his observations on living animals; Malpighi, four years after Harvey's death, by another observation on a full time income animal, completed the marvelous chain of evidence.

A second ground-breaking book published by Harvey in 1651, Essays on the Generation of Animals, is considered the basis for modern embryology.

In the seventeenth and eighteenth centuries, theories of embryology and development were superimposed with theories of sexual reproduction, plus a variety of theories on the origins of life, almost all of which supported the idea of spontaneous generation. During this time period debates raged over spontaneous generation, the idea that life was spontaneously created out of inanimate matter. The popular belief that living organisms propagated from mud in streams, dirt, or environments such as rotting meat was supported by a number of scholars. William Harvey's research into reproduction, published in 1651 as Exercitationes de Generatione Animalium (Essays on the generation of animals), started to cast doubt on spontaneous generation. Harvey believed that life reproduced sexually, a view that he stated along with his famous dictum Ex ovo omnia ("Everything comes from the egg").

Although he was taught by Fabricius, William Harvey criticized his teacher's views about reproduction. Actually, the inaccuracy he saw in Fabricius's beliefs prompted his investigation of animal generation (Book: The Ovary of Eve: Egg and Sperm and Pre-formation (The organism is preformed as a complete miniature structure in the sperm or the egg and simply grows larger as it develops. Which means that the first reproducing human would have had to have all succeeding generations within itself. Sort of like Russian dolls. ) ; author: Pinto-Correia, Clara; year: 1997). The flaws Harvey detected were in Fabricius's idea of the role semen played in reproduction. His teacher thought that after the male have been in contact with the female, all the eggs are created fertile. But upon his experimentation, Harvey learned that the hen laid an egg ten days after interaction with the male, and then another thirteen days after. Hence, he figured the male did fertilize several of the yolks.

Awards/ Prizes

William Harvey never won any awards or prizes, although he was made Doctor of Physic and Warden of Merton College (Oxford).

Summary

William Harvey was an English physician who, by observing the actions of the heart in animals like deer, and fishes, proved that heart receives and expels blood during each cycle of the circulation. By experiments and also on the basis of his teacher Fabricius's findings, he also found valves in the veins, and appropriately identified them as restricting the blood circulation in a single direction. He developed the first complete theory of the circulation of blood, believing that it was pushed throughout your body by the heart's contractions. He published all his observations and interpretations in Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus (1628), often abbreviated De Motu Cordis.

Harvey also noted, as earlier anatomists, that fetal circulation short circuits the lungs. He demonstrated that is basically because the lungs were collapsed and inactive. Harvey could not explain, however, how blood passed from the arterial to the venous system. The discovery of the connective capillaries would have to await the development of the microscope and the work of Malpighi, in 1661. He was largely influenced by the mechanical philosophy in his investigations of the blood circulation through the body. Actually, he used a mechanical analogy with hydraulics. Also, Harvey used quantitative methods to measure the capacity of the ventricles of the heart.

Harvey was the first doctor to make use of quantitative and observation methods simultaneously in his medical investigations, now known as the scientific method. In Exercitationes de Generatione Animalium (Essays Within the Generation of Animals, 1651), he was extremely skeptical of spontaneous generation and proposed that animals originally came from an egg. His experiments with chick embryos were the first ever to suggest the idea of epigenesis, the idea that an individual is produced by successive differentiation of any unstructured egg rather than by a straightforward enlarging of any preformed entity.

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