Medea, the sensual and ravishing sorceress of Greek mythology, enters the royal chambers. Knife in hand, she commands the servants to bring her an old sheep. Plunging her knife into the animal, she bleeds it nearly dry and then casts the limp sheep into a bubbling cauldron.  Its feeble bleating is soon replaced by the frolicking leaps of a young lamb. In this marvelous spectacle, Medea has demonstrated her ability to transfuse life to the dead and dying. 

Her husband’s enemy, the elderly and bedridden King Pelias, is next. 

Medea turns impatiently to the king’s daughters, who hover in a trance, drugged by the witch’s herbs and humbled by her otherworldly powers.  "Why do you hesitate and do nothing?" the enchantress snaps, "Go, now.  Draw your swords and drain out his old blood, so that I may fill his veins with young blood."

Slowly, the women approach their father, who looks up at them with trusting eyes.  Then, like ravenous beasts, they pounce.  Mimicking Medea’s brutal and precise cuts, the daughters deftly slice open Pelias’s veins and drain them dry. Medea flees the scene, smug in the success of her deception.

Rivers of blood run throughout human history—its wars, its violence, its science.  Medea is but one ancestor to an infamous cast of characters—some fictional, some real, all chilling and terrifying—who remind us of blood’s inextricable connections to life, love, revenge, and, above all, competition and power.  Long before Bram Stoker’s Dracula, Anne Rice’s Vampire Lestat, or television’s True Blood, acts of blood lust spiraled in stories told and retold.  

For the Ancient Greeks, blood was a magical elixir.  Pliny the Elder (AD 23-79), one of the great historians of the Roman Empire, described the mad rush of spectators into arenas to drink the blood of fallen gladiators.  Centuries later, Marsilio Ficino (1433-1499) similarly promoted drinking young blood as a means for the elderly to regain their youthful vigor. 

Blood transfusion is itself infused with brutality and legendry. By some accounts, the first transfusion was performed on Pope Innocent VIII in 1492; some claimed that he was transfused with or—at the very least—had drunk the blood of Jewish boys.  While skeptical historians rightly doubt that there is much truth behind this politicized papal story, what is certain is that where power and conflict are, blood stories are never far behind. 

Initially, natural philosophers, as the first scientists were called, were only able to imagine transfusion’s possibilities but could not persuade themselves to attempt the procedure.  The German physician Andreas Libavius speculated in the late sixteenth century that it could indeed be possible to transfer the blood of a healthy person into a sick one "to bring him the fountain of life and drive away all languor." Yet he closed his treatise (Appendix necessaria syntagmatis arcanorum chymicorum) with the firm conclusion that only a charlatan would be foolish enough to meddle in such unseemly experimentation.

If it was hard to imagine putting blood in, it was because much of early medicine was centered on taking blood out.  Since Antiquity, medical practitioners had subscribed to the idea that health and ill-health were a direct reflection of the fluids, or "humors," in the body.  When illness struck, it was a sign that the humors were out of balance.  And the quickest way to remedy was the imbalance was through bloodletting.

William Harvey’s discovery of blood circulation in 1628 shifted in dramatic ways how blood was understood.  His discovery did not abolish the notion of humors, which would continue well into the 19th century.  But Harvey’s theory of circulation  (and it was initially just that, a theory) paved the way for natural philosophers to begin imagining the possibility of putting things into veins and arteries for the first time.

Men like Christopher Wren, Thomas Willis, and Robert Boyle soon began injecting dogs with a variety of fluids—water, milk, beer, wine, opium—in order to test Harvey’s claims.  And by the 1660s, both the Royal Society and the French Academy of Sciences began performing canine-to-canine transfusion trials with varying levels of success.

There was a dizzying intensity to these experiments.  Natural philosophers and physicians were not only eager to explore the possibilities of transfusion; their blood experiments were at the forefront of what was, anachronistically speaking, something of a cold war for scientific dominance in late 17th century Europe.  To excel in science meant to solidify the glory of one’s country at a time of significant instability in the region.

In 1667, member of the English Royal Society and the French Academy of Sciences were caught by surprise when a young, upstart French physician named Jean-Baptiste Denis performed the first animal-to-human transfusion.  To the consternation of all, Denis transfused a feverish young boy with the blood of a lamb.  The boy survived.  The transfusionist then tried the lamb-blood procedure on a robust butcher—likely the same butcher who provided him with the sheep for the first experiment.  He, too, survived.  Emboldened, Denis plucked a mentally-ill man off the streets of Paris and performed a series of blood transfusions. 

Soon, the madman Mauroy was dead—and Denis was accused of murder. 

In the dramatic court case that followed, the Court determined that Mauroy had indeed been murdered—not by the transfusion itself, but by a cabal of physicians who wanted desperately to put an end to transfusion.  Transfusion, some feared, gave science a means to engineer new animal-human hybrids.  Would humans now begin to bark?  Or dogs become philosophers? 

For some, there was little to be worried about when it came to blood transfusion.  The philosopher René Descartes (“I think therefore I am”) had made the convincing argument of mind-body dualism.  Both animal and human bodies were little more than machines.  The only thing that differentiated humans from animals was that they had the ability to speak, think, and reason.  And these capacities were incorporeal; they were not connected to the body.  If this were indeed the case, then transfusing the blood of one species into the body of another would be—once again anachronistically speaking—little more complicated than changing the oil in a car. 

But what if Descartes was wrong?  What if the soul resided in the body?  Worse, what if the soul lived in the blood itself?  The very idea was frightening to some.  Frightening enough to lead them to take matters into their own hands.

In response to these controversies, the Court ruled that no further transfusions could take place without the express approval of the Paris Faculty of Medicine.  In so doing, the Court placed a de facto ban on the procedure.  The very men who plotted to kill Mauroy and to frame Denis were highly influential members of the Faculty of Medicine. And the Faculty had made its opposition to the theory of blood circulation and, by extension, blood transfusion abundantly clear. Transfusion research was over, and it would not re-emerge for another 150 years.

As the historian N.S.R. Maluf once wrote, "it is probably fortunate that blood transfusion took a nap for over one and a half centuries.  Ignorance of antisepsis, asepsis, and immunology—all 19th century discoveries—would have resulted in countless disasters."  This is likely true.  

But in the earliest battles for blood’s dominance, one thing is nonetheless certain…Medea would have been proud.

Images: top: Blood transfusion from animal to human, bottom: Blood transfusion (both in Public Domain, rights free, National Library of Medicine).

About the Author: Holly Tucker (blog, Twitter) is author of Blood Work: A Tale of Medicine and Murder in the Scientific Revolution (W.W. Norton).  She is Associate Professor in the Center for Medicine, Health & Society and the Department of French & Italian at Vanderbilt University.

The views expressed are those of the author and are not necessarily those of Scientific American.

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