Science

Don’t Chew the Wallpaper

A history of poison.

Napoleon Bonaparte

Think murder by poison, and Lucrezia Borgia comes quickly to mind. Willful, beautiful, sexually promiscuous, and by historical reputation ruthless, she was said to rival her brother Cesare and her father, Pope Alexander VI, in jealousy, intrigue, and homicide, dispatching those who thwarted her with a dash of white arsenic in their drinks. But in a recent biography— Lucrezia Borgia: Life, Love, and Death in Renaissance Italy—Sarah Bradford has contended that Lucrezia Borgia never killed anyone. Bradford argues that Borgia’s reputation was tarred by her family’s political enemies in Renaissance Rome and further blackened by Victorians who disapproved of her unrestrained sexuality and strong-minded independence. Her image might have been widely restored (or smeared) by a film about the Borgias that Oscar-winning director Neil Jordan was to begin shooting next month. Alas, the project has been canceled, so Bradford’s book may be all Borgia gets.

Whether or not Lucrezia Borgia used poison, the weapon was a great equalizer. Murder required administering a poison in repeated or large doses, tasks that women could conveniently perform since they were trusted with the preparation of food and the administration of medicines. As a group, women had plenty of reasons to commit murder, too—lack of economic opportunity, limited property rights, and difficulty in escaping the marriage bond. In his recent book Elements of Murder: A History of Poison, John Emsley describes multiple cases of women who killed to gain courtly power, get rid of husbands, collect insurance, cover up swindling and theft during domestic employment, and receive inheritances. In France, arsenic came to be called poudre de succession, “inheritance powder.” One marquise, a true experimentalist, tested dosages of arsenic for illness and death by sending gifts of food containing the substance to patients at a local hospital. She then poisoned her father to inherit his wealth and knocked off her two brothers so she would not have to share it.

The favored poisons of the late 19th century were also an appealing instrument of murder, at least for the villain, because their effects on the body were gruesome. Mercury, arsenic, antimony, lead, and thallium—the agents explored in Emsley’s grimly clinical primer—induced repeated vomiting and diarrhea and turned the body into wasting, stench-ridden flesh. Mercury and lead damaged the nervous system and brain, producing symptoms including depression, insomnia, tremors, fits, and coma. Thallium promoted joint pains, supersensitivity in the feet, paralysis of the facial area, and failure of the heart and lungs. The advantage to the murderer was that such symptoms closely resembled those of common diseases. Victims were usually consigned to their graves as dead of natural causes rather than objects of foul play.

Poisoning was also relatively easy to get away with for centuries because possession of the murder weapon was by no means a clear indicator of guilt. Would-be poisoners could easily obtain the requisite materials from the shops of apothecaries or chemists, under the guise of using them in small doses for a cosmetic or medical purpose. The ancient temptress Jezebel applied stibnite powder, an antimony compound, as mascara, and in the Middle Ages people ingested the element as an emetic for hangovers. In the 19th century, one Dr. Fowler concocted a popular arsenic-based medication that was prescribed for syphillis, neuralgia, lumbago, epilepsy, and skin disorders.

During the 19th century, however, the developing techniques of analytical chemistry increased the risk that a poisoner would be caught. The expert testimony of academic chemists, based on post-mortem detections of poisons in corpses, led to convictions. Prosecutions could run aground, however, because of deft defense attorneys and some experts’ scientific punctiliousness. In the 1870s, the Rev. Herbert H. Hayden, a married father and minister of a Methodist church in Rockland, Conn., was accused of poisoning his mistress, a young servant girl, whom he believed he’d gotten pregnant. At Hayden’s trial, which captured national attention, four professors testified to the presence of arsenic in the girl’s body. It was identical to an ounce of the element that Hayden had purchased from a drugstore—to get rid of rats around his house, he said—just hours before the murder. Hayden’s attorneys managed to cloud the prosecution’s case by repeatedly challenging the professors’ statements, and they persistently declined to swear that there was absolutely no doubt about their findings. He got off on a hung jury.

Emsley, an accomplished science writer based at Cambridge University, dons his own detective’s hat. He deploys recent scientific analyses of hair and exhumed bone, matches them against historical reports of victims’ symptoms, and offers plausible explanations of the victims’ bizarre behavior and mysterious or disputed deaths. Mozart probably died of antimony poisoning, Emsely finds, by taking multiple medications for both depression and miliary fever. The sudden demise of King Charles II of Britain, an alchemical experimenter, very likely resulted from the inhalation of intense mercury vapors. And apart from the symptoms attributable to his evident porphyria, a blood disease, King George III’s famous madness reads “like a textbook case of acute lead poisoning.” It led to delirium and a coma in 1788.

Then there’s Napoleon Bonaparte. Twenty years after he died in exile on St. Helena, Napoleon’s body was exhumed for reburial in Paris. The exceptional preservation of his corpse, which could be chemically tested along with years’ worth of hair cuttings, revealed that his body contained high levels of arsenic. The symptoms of Napoleon’s final illness were also consistent with arsenic poisoning. Armchair analysts theorized that he had been done in by the British or by a jealous husband. But Emsley argues that Napoleon was killed by his wallpaper—or more precisely, drawing on the work of an Italian scientist named Bartolomeo Gosio, by the green, arsenic-rich pigment in the wallpaper’s star pattern.

At the end of the 19th century, Gosio was prompted to investigate why so many Italian children were inexplicably sickening and dying. Physicians suspected arsenic poisoning. Gosio demonstrated that a microorganism that grew on the flour-paste backing of the wallpaper could turn the arsenic in it into a gas that was powerful enough to make people ill and even kill them. If Napoleon chose the colors of his wallpaper to commemorate his imperial colors, Emsley writes, “[H]e did himself no favours … though they reminded him of his glorious past.” Napoleon seems to have been a victim, like so many others, of a surreptitious killer. But he may have been poisoned by his own vanity rather than by a self-protective lover, a grasping wife, or a woman like the Lucrezia Borgia of historical repute.