The Works of William Harvey

Summary

Robert Willis's 1847 translation for the Sydenham Society gathers nearly everything Harvey published or left in finished form, prefaced by Willis's Life of Harvey and the text of his will. Its centre is the Anatomical Disquisition on the Motion of the Heart and Blood in Animals (Frankfurt, 1628), seventy-two pages that overturned fourteen centuries of Galenic physiology. From vivisection of many animals, Harvey shows that the heart's working stroke is its contraction, that the auricles and ventricles beat in sequence, and that the blood of the right ventricle reaches the left through the lungs, not through pores in the septum. He then calculates: even if each beat expelled only half an ounce, the heart would pass more blood in half an hour than the whole body contains, far more than food could replace. The blood must therefore return. Ligatures on the human arm, of the kind used in bloodletting, and the valves of the veins confirm that it flows out by the arteries and back by the veins. Two Anatomical Disquisitions on the Circulation of the Blood (1649), addressed to the Paris anatomist Jean Riolan, answer twenty years of critics. Harvey repeats that questions of fact are settled by the senses, not by the age of an opinion, adds new experiments, takes up Descartes's mechanical account of the heartbeat, and notes how fear, anger and shame visibly drive the blood. The Anatomical Exercises on the Generation of Animals (1651), the longest work in the volume, record decades of observation of the hen's egg, day by day through incubation, and of the does and hinds of King Charles's parks, which the king allowed Harvey to dissect during the rutting and breeding seasons. Harvey rejects the inherited teaching that the embryo forms from the mixed seed of both parents, argues that every animal begins from an egg or primordium, and names the process by which parts appear one after another epigenesis. He takes the blood as the first part to live, visible as a beating red point. Essays on parturition, on the membranes of the uterus and on conception follow. Shorter pieces complete the book: the autopsy of Thomas Parr, reputed to have lived 152 years, whose death Harvey ascribed to rich food and the smoky air of London; and letters of Harvey's last years to physicians in Germany, Italy, France and the Netherlands. Harvey still speaks of spirits, native heat and the dignity of the heart, and much of his embryology was later revised, but his method of observation, experiment and measure shaped the medicine that followed. The full public-domain text is attached.

Top Lessons

• Counting the blood

  The decisive step in De Motu Cordis is arithmetic. Harvey deliberately chooses low estimates for how much blood leaves the heart at each beat and still finds that in half an hour more blood is expelled than the body holds and far more than food could supply. The argument does not depend on exact numbers, only on their order of magnitude. Students can see how a simple quantitative question can defeat a long-accepted theory.

• The senses against antiquity

  In the second disquisition to Riolan, Harvey answers critics who would not abandon doctrines carrying the weight of the ancients. He replies that facts known by the senses wait on no opinion and that nothing is older or more authoritative than nature. He does not despise the ancients; he cites Aristotle and Galen constantly. His point is that respect for teachers does not oblige us to deny what we see, and that a Creator's works are the final court of appeal for questions of anatomy.

• Watching a chick become a chick

  On Generation records patient, repeated observation: eggs opened day after day of incubation, the first red pulsing point, the vessels spreading, the body forming part after part. From this Harvey concludes that the embryo is built up gradually rather than unfolded from a miniature already present, and coins the term epigenesis. His view that the blood lives first was later revised, but his insistence on watching the process in sequence set the pattern for embryology.

• The physician at the bedside and the deathbed

  Harvey was a working physician, and the volume shows it: the bled patient who faints, the Montgomery youth whose heart he touched through an old wound in the chest, the warning against midwives who hurry a labour, the autopsy of Thomas Parr. His explanations mix new physiology with older ideas of the non-naturals, air, diet and the passions. Students can study how a great discoverer still reasoned within the medicine of his time.

Verified Quotes

Medical Lens

The volume is a primary source for the history of physiology and of experimental medicine. De Motu Cordis establishes the circulation by vivisection, quantitative estimate, ligature of the human arm and the anatomy of the venous valves. The disquisitions to Riolan apply the circulation to phlebotomy, fainting and the bodily effects of the passions, an early physiological treatment of the relation between emotion and the body. On Generation and its appended essays are a major early modern source on embryology, labour and the placenta, and include sharp criticism of hurried midwifery. The Parr autopsy explains death in extreme old age by the older categories of the non-naturals, air and diet, and gives an early complaint about the coal smoke and filth of London air. Harvey's explanations keep native heat, spirits and much humoral language, so his medicine should be read as a bridge between Galenic and modern physiology rather than as modern physiology in Latin. Any retrospective diagnosis of Parr's final illness from Harvey's description is interpretive.

• De Motu Cordis, Chs. II-V

  Vivisection of cold- and warm-blooded animals, observed as their hearts slow, shows that contraction is the heart's active phase.

• De Motu Cordis, Chs. IX-XIII

  The calculation of blood expelled in half an hour, and ligature experiments on the arm as used in bloodletting, with the valves of the veins, prove the circuit.

• Second Disquisition to Riolan

  Bleeding flows more freely in a warm body; a timid patient who faints stops bleeding; anger, shame, fear and desire move the blood visibly; pain relieved by bleeding and cupping.

• On Generation, Exercise the Fifty-second

  Harvey examines the young son of Viscount Montgomery, who survived a chest injury with an open cavity, and touches the beating apex of his heart, finding it without sensation of touch.

• On Parturition

  Natural and unnatural labour, the placenta and after-pains, and criticism of young midwives who hasten delivery with oils and drugs and endanger the mother.

• Anatomical Examination of the Body of Thomas Parr

  Autopsy of a man reputed to be 152, with lungs congested and the cause of death referred to the change of air, diet and drink on coming to London.