Time Capsule

Eighteenth-century Europe was abuzz with the frequent discovery of invisible and mysterious forces. Newton proved the existence of gravity. Benjamin Franklin captured and experimented with electricity. And thousands of spectators gathered in Paris to watch French inventor Jacques Alexandre Charles harness invisible gases to take flight in the first hydrogen-filled balloon. So, when charismatic Austrian physician Franz Anton Mesmer claimed to have discovered yet another invisible force — one that, he said, coursed through every living thing and was the cause and cure of every physical ailment — the finding seemed entirely within the realm of possibility to people living in the Age of Enlightenment.

Mesmer discovered “animal magnetism” as a young doctor in Vienna. Borrowing from the theories of a colleague, he attempted to cure patients by placing magnets on them. However, he soon discovered that the magnets were superfluous — all he really had to do was bring his hands near patients to affect miraculous cures. He tamed the throat spasms of a young baron, stilled a sleep-walking professor and cured a young woman with a mysterious, blistering illness. But after a more-or-less failed attempt at restoring the sight of blind piano prodigy Maria Theresa Paradis, Mesmer fell out of favor in Vienna and decamped to Paris in 1778.

There, word of Mesmer’s cures spread quickly, and the doctor soon found himself with more patients than he could treat. To meet demand, he trained disciples and developed a way to treat a dozen patients at a time. He’d wave his hands over bottles of water, thus “magnetizing” them, and place the bottles in a tub filled with water and a layer of metal fillings. Iron rods protruded from the tub, and patients touched them to their ailing body parts. Mesmer directed the “magnetism” by walking around the tub and touching his patients, often on their abdomens and inner thighs. A musician playing a piano or glass harmonica — an instrument with the eerie sound of a finger on the edge of a wine glass — accompanied the treatment.

Mesmer made a fortune running several clinics and attending private parties, often of upper-class women. The ladies would convulse, scream and faint as Mesmer waved his hands over them or touched them. The potential indecency of the gatherings— and the fact that some of Mesmer’s disciples began espousing revolutionary ideas — attracted the attention of King Louis XIV. On March 12, 1782, the king appointed two commissions to investigate Mesmer’s claims. One was led by Benjamin Franklin, the U.S. ambassador to France at the time, and eight eminent scientists, including Antoine-Laurent Lavoisier, the father of modern chemistry, and Dr. Joseph-Ignace Guillotin, a medical reformer who became famous for pushing France to devise a more humane, mechanized way of carrying out the death penalty. The other commission included members of the Royal Society of Medicine.

The commissioners conducted several tests to determine whether animal magnetism was real or imagined. In one experiment, they tricked a young woman into believing that Mesmer disciple Charles d’Elson was in an adjacent room, directing animal magnetism toward her through a closed door. The woman responded by falling into convulsions and biting her hand so hard she left a mark. Another young woman drank water she believed to have been magnetized, but wasn’t. She fainted, and was given a bowl of water to drink to revive her — water that, unbeknownst to her, had been “magnetized.” That bowl of water had no effect.

The experiments proved that animal magnetism was not real, and its apparent effects were actually due to people’s belief in the power of Mesmer and his colleagues. Even d’Elson was convinced, concluding that “the imagination thus directed to the relief of suffering humanity would be a most valuable means in the hands of the medical profession.”

In effect, Franklin and his colleagues discovered that the true source of Mesmer’s power came from his patients, who cured themselves — or at least mitigated their symptoms — through the power of their own minds. Since then, psychologists and medical hypnotists have refined that process, helping people endure painful surgery without anesthetic, for instance. But perhaps the most valuable contribution Franklin and his colleagues made was designing the first placebo-controlled blind trial, laying the foundation of modern medicine and science.

Kathy Milar, PhD, of Earlham College is historical editor of “Time Capsule.”


  • Best, M.A., Neuhauser, D., & Slavin, L. (2003). Benjamin Franklin: Verification & validation of the scientific process in healthcare. Victoria, British Columbia: Trafford.

  • Darnton, R. (1970). Mesmerism and the end of the enlightenment in France. Oxford, England: Schocken.

  • Gallo, D.A., & Finger, S. (2000). The power of a musical instrument: Franklin, the Mozarts, Mesmer, and the glass armonica. History of Psychology, 3, 326–343.

  • Lopez, C.A. (1993). Franklin and Mesmer: An Encounter. Yale Journal of Biology and Medicine, 66, 325–331.

  • Pattie, F.A. (1994). Mesmer and animal magnetism: A chapter in the history of medicine. Hamilton, N.Y.: Edmonston Publishing.