Theory of circulation by respiration

In Short

Written as an open letter to a sympathetic physician, this 1861 treatise outlines Emma Willard’s long crusade to overturn William Harvey’s accepted model of cardiovascular physics. Willard argues that atmospheric oxygen combining with carbon in the lungs acts as a chemical engine, expanding blood and generating steam that propels the fluid through the body. Blending personal medical anecdotes, laboratory experiments with rubber tubing, and reports of revived drowned animals and cholera patients, the work documents a nineteenth-century woman’s determination to force mainstream medical authorities to accept her self-discovered physiological truth.

The Story

The narrative opens as Emma Willard addresses Dr. Marcy, detailing how she spent thirty years developing and defending her alternative theory of blood movement. Disbelieving that the heart alone possesses enough mechanical strength to push blood throughout the whole body, she looks back to 1832, when the outbreak of Asiatic cholera prompted her to re-examine the mechanics of animal heat. She reasons that chemical combustion occurs exclusively in the air-cells of the lungs, expanding the water in the blood and forcing it into the left ventricle. Finding that simple liquid expansion cannot match the known speed of blood flow, she refines her model: inside the partial vacuum of the lungs, warm blood flashes into vapor, driving circulation much like a steam engine.

To support her claims, Willard details physical experiments using endless rubber tubes filled with water. Heated at one point and cooled at another, the liquid moves continuously, while manual squeezes merely regulate the pulse. She translates this theory into personal practice, recounting how she saved herself from freezing during an 1835 winter stagecoach ride by deliberately hyperventilating to ignite internal pulmonary heat. During the 1849 cholera epidemic, she applies the concept to others, forcefully dragging a collapsed, pulseless servant named Jane Phayre into the fresh air and forcing her to breathe deeply until red life returns to her face.

Throughout the prose, Willard chronicles her relentless efforts to get her writings published and reviewed. She experiences bitter dismissals from established medical journals, whose male editors politely urge her to return to female education. Undeterred, she tracks the gradual acceptance of her ideas among independent doctors. She highlights public demonstrations in Louisiana, where Dr. Cartwright uses a blowpipe in a dissected trachea to repeatedly revive a dead alligator, and describes a practitioner who successfully resuscitates his own dying infant using artificial pulmonary inflation. The text culminates in a triumphant victory lap, citing supportive medical articles from Missouri and Tennessee that declare opposition to her system completely crushed.

How It Unfolds

A spark of skepticism Dissatisfied with standard teachings on the heart's mechanical output, Willard studies animal heat during the 1832 cholera outbreak and concludes that pulmonary combustion expands blood, creating its primary motive force.

Testing the hydraulic model Using rubber tubing, water, and localized heat, Willard constructs mechanical models showing that thermal expansion generates continuous flow, while rhythmic pressure simply acts as a regulating valve.

Rejection by the faculty After publishing her manuscript in 1846, Willard encounters cold silence and sharp reviews from traditional physicians who argue that body heat is generated universally in tissue rather than solely in the lungs.

The discovery of steam Realizing thermal expansion alone moves too slowly, Willard factors in the vacuum environment of the lungs, asserting that blood turns to vapor at low temperatures to drive circulation like a steam engine.

Bedside verification Willard tests her ideas during health emergencies, using deep, forced breathing to rescue herself from intense sub-zero cold and to restore a cholera-stricken household servant from the brink of death.

Vindication in the laboratory Prominent southern doctors adopt the theory, demonstrating its principles by using tracheal inflation to repeatedly bring a dead alligator back to life and to save a dying child.

The People

• Emma Willard: The author and educator who spends three decades researching, experimenting with, and defending her novel theory of thermal and steam-driven blood circulation despite social and professional opposition.
• Dr. Marcy: A supportive physician and editor of the U. S. Journal of Homoeopathy, to whom the text is addressed as a formal historical report.
• Jane Phayre: Willard's twenty-five-year-old Irish domestic servant who collapses with deadly cholera symptoms and is restored to health through forced outdoor breathing exercises.
• Dr. Cartwright: An eminent physician from Natchez and New Orleans who publicly tests Willard's theory by performing resuscitation experiments on alligators.
• Dr. Ely: A skeptical doctor who reverses his opposition to Willard's work after using her pulmonary inflation methods to revive his own infant son three times from fatal collapse.
• Dr. B. F. Washington: A Missouri medical writer whose journal articles vigorously defend Willard's system and defeat its critics in open debate.

In Its Own Voice

"It is into the lungs, and no where else, that breathing introduces atmospheric air; and it is there that the oxidation of carbon or animal combustion takes place."

Willard lays out the foundational chemistry of her system while analyzing the fatal coldness of cholera.

"The heart we regard as the grand regulator of the blood's flow; and it is admirably situated for measuring out a regular portion of blood at every contraction."

Refuting Harvey, Willard explains the true, secondary role her mechanical experiments assign to the cardiac muscle.

"And I soon found what I thus sought, and then discerned for the first time that the blood moves, as does the railroad car, by steam."

Willard describes the breakthrough realization that fluid vaporizing inside the lungs provides the true impelling force of human life.

What It's Really About

At its core, the text is an intense argument for a central, unifying physical law in human physiology. Willard seeks to replace what she views as clunky, unscientific explanations of the heart's workload with an elegant system based on thermodynamics, fluid expansion, and pneumatic pressure. Beneath the medical debate lies a passionate defense of natural theology, as Willard insists that discovering the true mechanics of blood flow vindicates the wisdom of the Creator. The work also functions as an assertive feminist manifesto, documenting the barriers faced by an independent female thinker invading a male-dominated scientific field, and insisting that empirical truth belongs to whoever observes it accurately.

Why Read It Today

This book offers a fascinating, highly readable glimpse into nineteenth-century alternative science and the history of American women in self-directed research. Readers who enjoy unusual historical medical debates will be drawn to Willard's vivid, unpretentious voice, which moves effortlessly between formal physiological arguments and dramatic first-person survival stories. While modern readers will quickly recognize that her central thesis—that blood moves by steam generated in the lungs—is medically incorrect, the book remains compelling because of Willard's sharp logic, clear mechanical analogies, and direct observational style. It captures the raw energy of an era when lay researchers routinely challenged elite academic orthodoxies using basic household items, sheer determination, and personal conviction.