ThePoisonersArsenic, the Secret Weapon of Women in History

In England, the jurist William Blackstone summed up the legal condition of a married woman: "by marriage, the husband and wife are one person in law," and the very legal existence of the woman is "suspended." Whatever she signs during the marriage is void, or at least voidable; she can bring no legal action for redress without her husband's concurrence, and in his name.

To undo a marriage required a private Act of Parliament: a thousand pounds at a conservative estimate, if nobody opposed it. Between 1670 and 1857, Parliament granted more than three hundred divorces in this way. Only four went to wives.

Arsenic, by contrast, required no signature. Before 1851, a woman could buy enough to kill for two pence. People used it against vermin, and it turned up in wallpaper, sweets, and the paint on children's toys. Swallowed, it produces what the WHO still describes today: vomiting, abdominal pain, diarrhea—indistinguishable from the cholera and gastroenteritis of the day. The doctor saw one more stomach patient, wrote down "gastric fever," and was not entirely wrong.

The Sicilian legend begins with a very real execution: Thofania d'Adamo, a poisoner in Palermo, was executed in 1633. Giulia, said to be her daughter and to have lent her name to "Aqua Tofana," the poison of legend, died in her sleep in 1651 without anyone suspecting her of a thing. Even her name and her kinship with Thofania are held by historian Craig Monson to be the invention of an 1880s historian.

The real trial began in Rome on January 31, 1659, when a poison dealer, Giovanna De Grandis, was caught in the act. She named names—her associates and her clients—and more than forty people ended up in the investigation. On July 5, five women were hanged in the Campo de' Fiori, including Gironima Spana. They were poor women. The clients, for their part, got off with immunity, exile, or house arrest, and the noblewomen were pardoned: papal justice hanged the manufacturers and spared the buyers, which remains the most Roman way of handling retail trade.

And the six hundred husbands? According to Craig Monson, the women hanged in 1659 did not call their poison "Aqua Tofana" and had not killed their husbands; two of them were even happily married. The number and the network of avenging wives came afterward, when "centuries of storytelling," as the Folger Shakespeare Library puts it, rewrote the story.

The French gave arsenic a nickname that confesses the motive: poudre de succession—"inheritance powder." People poured it to inherit sooner.

The Marquise de Brinvilliers poured it inside her own family. In the letters found at her lover's residence, she claimed to have poisoned her father, Dreux d'Aubray, civil lieutenant of the Châtelet of Paris, in 1666, and then her two brothers in 1670, one of them civil lieutenant in his turn, the other a counselor at the Parlement. The motive was the very one named by the powder: seizing the family estate. Her husband escaped the same fate only through caution.

The affair began with a casket. In 1672, upon the death of Godin de Sainte-Croix, investigators found inside it the letters of his mistress, the Marquise de Brinvilliers. Arrested in a convent in Liège in 1676, she was beheaded at the Place de Grève that same year. Police lieutenant La Reynie then traced the network to a fortune-teller, Catherine Deshayes, known as La Voisin, who sold powders and abortions. She was burned alive at the Place de Grève on February 22, 1680.

To judge these cases, Louis XIV created a special court in 1679, the Chambre ardente. Over three years, it saw hundreds of suspects pass through. The king dissolved it in 1682; that same year, a royal act regulated the sale of arsenic.

The investigation quickly spilled beyond poison: as the French Ministry of Justice sums it up, it soon involved "abortions, magic, hexes, spells, and other Black Masses." After the execution of La Voisin, her daughter directly implicated Madame de Montespan, Louis XIV's favorite and the mother of seven of his children. No evidence backed up the confessions, and many accusations, notes the Encyclopædia Universalis, were doubtless inflated by suspects subjected to torture. Even so, the king instructed the Chamber to stop touching any case in which that name appeared. It had questioned 442 suspects and ordered 367 arrests; when the king suspended its proceedings in 1682, *the remaining suspects were dispersed into royal prisons by lettres de cachet, without trial.*

In 1832, English police arrested John Bodle for allegedly lacing his grandfather's coffee with poison. James Marsh, a chemist at the Royal Arsenal in Woolwich, detected it in the form of a yellow precipitate. By the day of the trial, the precipitate had deteriorated; for lack of proof, Bodle was acquitted. He confessed later. English law does not try the same man twice; Marsh decided that the forensic proof, at least, would never again rot before the hearing.

His test, published in 1836, converts arsenic from body tissue into a gas that deposits onto a cold dish as a silvery-black stain—a stain that can be shown to a jury months after the funeral. The poison that mimicked cholera finally left a signature.

Four years later, France had its great arsenic trial. Charles Lafarge died at Le Glandier on January 14, 1840. Chemists from Tulle and Limoges found no trace of arsenic; Mathieu Orfila, dean of the Paris Faculty of Medicine, repeated the analysis and found it. His widow, Marie Lafarge, was sentenced on September 19 to life at hard labor. Historians still debate the rigor of Orfila's procedures. Nobody debates the principle anymore: a dead body could now take the witness stand.

Never before or since has England hanged such a high proportion of women. Between 1843 and 1852, more than one in five executions in England and Wales was that of a woman, and most of them had used arsenic.

The Arsenic Act of 1851 answered with paperwork. The seller had to keep a signed register, require a witness if the buyer was unknown to him, and sell only to adults; the powder had to be colored with soot or indigo so it could no longer be mistaken for another white powder. The poisoners, for their part, had never confused the packets. The House of Lords approved the bill on the eve of Sarah Chesham's hanging at Chelmsford, on March 25, 1851, for attempting to poison her husband: the kingdom was tackling the problem from both ends, the register and the rope.

Mary Ann Cotton was nothing like a trapped wife. Born in 1832 at Low Moorsley in County Durham, she married four men and buried three of them. After the death of the first, William Mowbray, she collected thirty-five pounds in life insurance. The third, James Robinson, refused to insure his life and threw her out when he discovered withdrawals from his account: he was the one who survived. Around her there also died her mother, a fiancé, and eleven of her thirteen children. Depending on the source, she is credited with between fourteen and twenty-one murders.

In July 1872, a parish official, Thomas Riley, asked her to help nurse a woman ill with smallpox. She answered him by speaking of her stepson, Charles Edward: "I won't be troubled long. He'll go like all the rest of the Cottons." Five days later, she reported his death. At the insurance office, she was told that no money would be paid out without a death certificate; and Riley, who had heard her remark, had persuaded the doctor to delay issuing the certificate. Dr. Kilburn's tests found arsenic. Other exhumed bodies contained it as well. Tried solely for the murder of Charles Edward, she was hanged at Durham on March 24, 1873.

Nagyrév, in Hungary's Tiszazug region, had no hospital. It had a midwife, Zsuzsanna Fazekas, who delivered babies, performed abortions, and knew how to extract arsenic from flypaper. During the First World War, the husbands were away at the front and the village housed Allied prisoners of war; many wives took lovers. When the men returned, they resumed their old lives.

The women started with their husbands. Some then moved on to parents who had become a burden, to lovers, and sometimes to their own sons. The deaths attributed to them stretched from 1911—even before the war—to 1929, until an anonymous letter sent to the editor of a small local newspaper accused the women of the Tiszazug of poisoning their relatives. When police arrived to arrest Zsuzsanna Fazekas on July 19, 1929, she was already dead.

Graves were exhumed. Twenty-eight suspects stood trial, all but two of them women; six were sentenced to death and three were hanged. The figure of three hundred victims still circulates in popular accounts. Historian Béla Bodó, however, sticks to the confirmed deaths: forty-five to fifty.

In 2015, Marissa Harrison, a psychologist at Penn State, and her co-authors combed through press records on sixty-four American female serial killers from 1821 to 2008. Their most common motive was financial gain, and their most common method was poison. The life-insurance widow has not vanished; she has simply found steady employment, since nearly four in ten, according to Harrison, were nurses or healthcare workers.

Yet one of the most prolific serial killers in modern history was an English family doctor: Harold Shipman killed at least 215 of his patients, most of them elderly women, with diamorphine. The grandmother killed by her doctor replaced the husband killed by his wife: poison follows trust, not sex.

The stereotype is older than Shipman. The "fathers" of criminology, Cesare Lombroso and Otto Pollak, defined poisoning as a female crime on account of its "masked character." English court records do not back them up: according to historian Katherine Watson, from 1750 to 1914, men accounted for 48% of all people prosecuted for poisoning in England.

One of them practiced medicine in his hometown of Rugeley, in Staffordshire. William Palmer had taken out three life-insurance policies on his wife totaling £13,000; she died in September 1854. He next insured his brother Walter, who died the following summer. He was tried only for the death of his friend John Parsons Cook, poisoned according to the prosecution with strychnine, and was hanged outside Stafford Prison on June 14, 1856, maintaining his innocence.

Arsenic was not the secret weapon of women. It was everyone's secret: the grocer who sold it, the doctor who missed it, the insurer who paid out, the law that left no other door open. It took a glass tube to make the dead speak.