De Motu Cordis: the Lumleian Lecture of 1616: an imagined playlet concerning the discovery of the circulation of the blood by William Harvey.

William Harvey's discovery of the circulation of blood is one of the greatest achievements in science. He sought to answer the following questions: What is the relationship of the motion of the auricle to the ventricle? Which is the systolic and which is the diastolic motion of the heart? Do the arteries pulsate because of the propulsive force of the heart? What is the purpose of the cardiac valves?... the venous valves? How does blood get from the right to the left ventricle? What is the direction of blood flow to and from the heart? How much blood is present in the body and how long does its passage take? Without knowledge of the capillary circulation, Harvey concluded that ‘. .. the blood is driven into a round by a circular motion and that it moves perpetually; and hence does arise the action or function of the heart, which by pulsation it performs.’ His revolutionary concept, first presented to the College of Physicians in 1616 and published in 1628, became accepted in his lifetime. The following playlet is a condensed, imagined version of Harvey's De Motu Cordis, assembled from several authoritative English interpretations of his book (which was written in Latin).1-3 Notes from Harvey's lectures are available, and it appears that he did not present his finalized conception of the circulation at the public anatomy of 1616, as depicted, but that his insights evolved over a number of Lumleian Lectures and private anatomies over a period of several years.4 Exercitatio anatomica de motu cordis et sanguinis in animalibus (An anatomical disputation of the movement of the heart and blood in animals), known as De Motu Cordis, was finally published in 1628 as a 72 page, poorly bound paper edition containing many printing errors.1,5 Harvey's magnificent achievement—considered to be one of the greatest in science as well as the introduction of experimental observation—was controversial, but it eventually became accepted in his lifetime, except in Paris where it was severely criticized by Jean Riolan, a respected anatomist. Harvey's practice suffered initially, and, according to a comment made by Harvey, some thought he was ‘crackbrained.’6 Later, his reputation was reestablished, and he was venerated by his colleagues and the public. His practice included nobility as well as the poor, and he became a consulting physician to King James I in 1618 and the personal physician to King Charles I in 1625. When King Charles was opposed by Cromwell and the Parliament, Harvey was forced to flee with the King to Oxford. His valuable papers and notes were destroyed by the Puritan forces. After returning to London in 1646, he retired from practice at the age of 68. In 1651, aged 73, he published Exercitationes de Generatione Animalium, a forerunner of modern embryology. When Malpighi demonstrated the capillary circulation in 1661, Harvey's circulation of the blood received its final proof, which he had postulated but was unable to prove before the microscope. Harvey gave the Lumleian lecture intermittently until 1656, and he was active in the Royal College of Physicians as treasurer, censor, and on committees to oppose quackery and maintain standards of conduct; he declined its presidency because of ill health. He left his estate to the college and endowed its library and a museum. Harvey suffered severely from gout and, in 1657, died of a stroke at the age of 79. A marble bust and portrait of William Harvey, and the wand that he used to demonstrate anatomy, is on display at the Royal College of Physicians (Figure 1). The Harveian Oration continues as an esteemed annual lectureship and banquet.4,7 In 1906 the oration was delivered by William Osler, who said ‘By no single event in the history of science is the growth of truth, through the slow stages of acquisition, the briefer period of latent possession, and the for us glorious period of conscious possession, better shown than in the discovery of the circulation of the blood.’7 Figure 1 Wand used by William Harvey during his Lumieian demonstrations. Photograph copyright of the Royal College of Physicians of London and used with permission.