In the late 1820’s and 1830’s American physicians found themselves with a major rebellion on their hands. The rebels were their own patients, or ex-patients, and the rebel leader was a onetime New Hampshire farmer and itinerant herb-and-root doctor named Samuel Thomson, who had published, in 1822, a book called Thomson’s New Guide to Health; or, Botanic Family Physician.

On Thomson’s recommendation, hundreds of thousands of Americans were no longer calling in conventionally trained and licensed physicians when they were sick. Instead, they were either doctoring themselves according to the instructions contained in the New Guide to Health , or were consulting disciples of Thomson who had set themselves up in business as botanic healers.

It was Thomson’s passionate conviction that most physicians of the day were no better than torturers and murderers. Their chief crime against suffering humanity, he argued, was their insistence on dosing patients with “metallic” medicines, by which he mainly meant calomel, a widely used and horribly effective cathartic whose active ingredient was mercury. In Thomson’s view, the way to cope with illness was to administer certain herbal remedies—he particularly favored lobelia, a powerful emetic—and to put the patient in a steam bath to make him sweat. Thomson held that it was possible by using these methods to cure every disease known to man, from dyspepsia and croup to cancer and tuberculosis.

Thomson’s rebellion was launched at a time when American physicians had been trying, with some success, to enhance their status (and incomes) by putting the practice of medicine on a more professional footing. Before the Revolution, and for some time afterward, in most parts of America anyone with a mind to do so had been at liberty to treat sick people and to call himself a doctor. But in the early 1800’s the country’s “regular” physicians, led by graduates of the medical schools of Columbia, Harvard, and the University of Pennsylvania, set out to change this. At their behest, state after state established licensing requirements for physicians and imposed penalties on persons practicing medicine without a license. At the same time, new medical schools were founded in the South and West, and young men were entering the profession in such numbers as to assure, before many more years, an adequate supply of licensed physicians for all but the most remote and sparsely settled regions of the country.

The nation’s growing medical establishment began to react vigorously—and understandably—to the threat that Thomson posed to its members’ self-esteem and to their pocketbooks. His notions about medicine were denounced as at once laughable and dangerous. In a book called Humbugs of New-York a New York physician named David Meredith Reese expressed the prevailing view in medical circles when he dismissed Thomsonian practitioners as uneducated quacks, noting by way of proof that their principal remedies were commonly known “by the classical and euphonious names of screw augur! ram-cat! and hell-scraper! ” These names clearly point to the emetic action of lobelia, which was also known, for reasons that are not so clear, as “belly-my-grizzle.”

Reese went on to charge that if anyone was killing innocent patients, it was the Thomsonians, whose medicine, he explained, had “systematic arrangements for clandestinely murdering its victims” in infirmaries where patients were “taken care of on the Thomsonian plan, until they either run away … or are quietly buried.” (Thomson himself, early in his career, had been tried for the murder of one of his patients.) State and local medical societies called on the authorities to deal harshly with unlicensed practitioners, and some Thomsonians were actually thrown into jail.

But such tactics were unavailing. Between 1822 and 1839 the New Guide to Health went through thirteen editions and sold more than 100,000 copies. This was an astonishing total considering that the population of the United States in 1839 was less than seventeen million, and that a copy cost twenty dollars.

Thomsonians also founded, and supported with their subscriptions, some forty journals in which the theory and practice of Thomsonian medicine were expounded. Their pages were filled with stories of the miraculous healing powers of Thomsonian remedies. Typically these accounts told of patients who had been left for dead by their regular doctors—the latter were customarily referred to in terms like “these slick-tongued, high-minded, small-pill-bag, metallic gentry”—and had been restored to robust health within twenty-four hours after swallowing their first dose of belly-my-grizzle. In one variation of the formula it was reported that an old lady in Crawford County, Missouri, had polished off most of a bottle of tincture of lobelia under the mistaken impression that it was whiskey. “I thought I would die,” she was said to have told a local Thomsonian practitioner. “But sir, I did not die; for I commenced puking … and please God, sir, I have not had one hour’s sickness since.”