Harvey Demonstrates the Circulation of the Blood
A London physician uses ligatures and volume estimates to show the heart pumps blood in a loop
Quick facts
- Physician
- William Harvey, 1578 to 1657
- Work
- De Motu Cordis, 1628
- Method
- Ligature experiments and blood-volume estimation
- First presented
- 1616 Lumleian lectures, Royal College of Physicians
What happened
William Harvey, physician to King James I and King Charles I and a graduate of the University of Padua's medical school, published Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus, On the Motion of the Heart and Blood, in Frankfurt in 1628. Galenic medicine had held that blood was continuously produced by the liver and consumed by the body's tissues, ebbing and flowing rather than circulating in a fixed loop. Harvey combined observation of comparative anatomy across animal species with mechanical reasoning: he estimated the volume of blood the heart pumps in an hour and showed it far exceeds what the body could plausibly manufacture and use up in that time, and he used tight ligatures on arms and vessels to demonstrate that blood flows outward from the heart through arteries and returns through veins, moving in one direction through valves that prevent backflow. Harvey had first presented these findings in the 1616 Lumleian lectures at the Royal College of Physicians, refining the argument for over a decade before publishing.
Why it matters
Harvey's book undermined the Galenic model of blood production and consumption that had stood for roughly 1,400 years and established that the body works as a closed mechanical system, a circulatory loop, rather than a site of continuous production and absorption. It gave physiology a demonstration that hydraulic reasoning and quantitative estimation, not textual authority, could resolve a question about how a living body actually works.
How we know
Harvey's original Latin treatise survives and was translated into English in 1653; the University of Texas Medical Branch's Osler history collection and the Fordham University sourcebook, which reproduces Harvey's own dedication and argument, both document his method of ligature experiments and blood-volume estimation from the printed text itself.
Sources
- University of Texas Medical Branch, Osler Hall of Medical History. William Harvey · Reputable sourceutmb.edu · The domain "utmb.edu" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
- William Harvey, trans. Robert Willis, via Fordham University Internet Modern History Sourcebook. On the Motion of the Heart and Blood in Animals, 1628 · Primary source (author-declared)sourcebooks.fordham.edu · Cited as a "primary" source (no stronger domain match). · Link is live and its text matches the event's key terms (Jul 2026)
See something wrong? . Corrections with a source get fixed fastest.
Part of a timelineThe Scientific Revolution20 events · How observation and mathematics replaced ancient authority between 1543 and 1727View all →