by E. J. Wagner
Although reptiles and the odd amphibian were the most common sources of poison in the ancient world, plant poisons were also known. Hemlock, oleander, monkshood, hellebore, opium, and various unsavory varieties of mushrooms took their toll on unsuspecting victims.
Arsenic was known, but its distinctive taste limited its use as part of the poisoner’s arsenal until about A.D. 800, when an Arab researcher named Jabir ibn Hayyam refined it into a white powder with little taste, which was easily hidden in food or drink. With grim humor, people referred to arsenic as “inheritance powder,” as unhappy families were believed to make efficient use of it. Although it was often a suspected cause of death, its presence could not be clearly demonstrated in a court of law.
During the Middle Ages, the pervasive fear of poisoning led to complex but ineffective antidotes and superstitious methods of detection. It was believed that black spots appearing on a corpse denoted the presence of poison, thus confusing natural signs of putrefaction or disease with evidence of homicide.
Supposed universal antidotes included dried powdered mummy, “unicorn horn” (this was usually the relic of an unfortunate rhinoceros), and theriac, a concoction that consisted of thirty to sixty ingredients, depending on the recipe of the apothecary mixing it. It was useless to the patient, although most helpful to the financial situation of the consultant.
Usnea, made of moss scraped from the skull of a dead man, preferably that of an executed criminal, was a favorite “cure.” There was also a brisk business in bezoar stones. These are accretions usually formed in the intestines or gallbladders of animals, and they were bought at enormous cost by many credulous heads of state.
Ambroise Paré, a sixteenth-century surgeon possessed of scientific skepticism and a spirit of inquiry worthy of Sherlock Holmes, insisted bezoars were without value and was determined to prove the point. As a medical adviser to Charles IX of France, he was in a good position to do so. He chose for his experiment a palace cook who had been accused of stealing some silver and was therefore languishing in prison while he awaited execution. Paré proposed to feed the cook a poison and then administer part of the king’s prize bezoar stone as antidote. The prisoner would be granted a pardon if he survived.
Eager for a chance at life, the cook agreed to the trial. Within an hour, in spite of the bezoar stone, the cook was in agony, crawling on all fours, vomiting, purging, and bleeding from every orifice. Paré’s attempts to assuage his suffering were of no avail, and the hapless man expired after seven hours of torment. Charles destroyed the bezoar stone as a result, although there were some at court who believed that Paré had proven not that bezoars were worthless but only that Charles’s bezoar was a counterfeit.
Paré’s use of human beings in poison experiments in the sixteenth century was not unique, and fear of such activities was deeply embedded in folklore. Catherine de Medici was popularly believed to have brought poison recipes along with her dowry when she wedded the French king. It was whispered that she sent baskets of poisoned food to the poor and then ordered her servants to visit the recipients the next day and inquire about their health. This procedure, people claimed, allowed her to add to the body of scientific knowledge while conveniently reducing the number of impoverished citizens in France.
The image of the murderous woman tied neatly in with the fear of witchcraft and magic. In the seventeenth century, an inventive lady called Teofania di Adamo sold a clear fluid to the ladies of Rome and Naples labeled “Manna of St. Nicholas of Bari.” It was officially known as a cosmetic, but a tiny amount was said to cause a rapid death that featured a natural appearance. It became known as “Aqua Tofana.” Difficult husbands began to experience fatal digestive complaints.
When at last official suspicion focused on Teofania, she sought refuge in a convent, from which she was eventually expelled. Under intense questioning, she confessed to more than six hundred murders and was promptly strangled. Her daughter, Giulia, is believed to have carried on the family business. Following as well in her treacherous footsteps was a French woman, Madame de Brinvilliers, who separated a number of relatives and lovers from life before she was caught and executed.
Both Aqua Tofana and Madame de Brinvilliers are mentioned by Watson in A Study in Scarlet when he sardonically sums up a newspaper article:
After alluding airily to the Vehmgericht, aqua tofana, Carbonari, the Marchioness de Brinvilliers, the Darwinian theory, the principles of Malthus, and the Ratcliff Highway murders, the article concluded by admonishing the government and advocating a closer watch over foreigners in England.
Until the early nineteenth century, convictions for poisoning depended on circumstantial evidence and confessions elicited by torture. When Mary Blandy was tried and hanged for poisoning her father in 1752, the medical evidence against her was merely that the white powder she was seen putting in her father’s food looked like arsenic and that the deceased’s intestinal tract was irritated.
By 1814, it was clear that progress was being made, largely due to the efforts of Mathieu Joseph Bonaventure Orfila, who was born on the Spanish island of Minorca in 1787. A brilliant student of medicine and chemistry, he left Spain for Paris at the age of eighteen to continue his studies. In the course of his research, he discovered that many of the primitive tests for poisons and their antidotes were worthless, and he embarked on new experiments that he designed himself.
Orfila’s first publication, Treatise on Poison, established the new science of toxicology as a vital part of medical jurisprudence. He demonstrated the effects of arsenic and other poisons on the intestinal tract by experimenting on dogs and developed new methods of recovering arsenic from animal tissue.
Building on Orfila’s work, a chemist from the British Isles, James Marsh, invented the first test for heavy metal poisoning that produced results vivid enough to convince a jury. The device was simple. A glass tube shaped like a U, with one open end and a pointed nozzle at the other end, was made. Zinc was suspended in the pointed end; in the other end, the suspect fluid was mixed with acid. When the liquid and the zinc met, if arsenic was at all present, arsine gas emerged from the nozzle. A flame was held to the gas until it ignited, and an icy piece of porcelain was placed near the flame. A black, shiny deposit called an arsenic mirror would form on the china. It was a mirror that could reflect a murder. The Marsh method was capable of finding even minute quantities of arsenic as well as antimony. It was dramatic enough to impress a courtroom.
It produced the crucial evidence at the 1840 trial of Marie Capelle Lafarge, who was accused of eliminating an ill-mannered husband with arsenic-laden cake. Born in 1816 to parents who, it was rumored, had blood ties to the French nobility, Marie was orphaned as an adolescent and raised in Paris by an aunt and uncle. Sent to expensive schools, she made friends among the wellborn, but as she had only a modest dowry, she was not considered an attractive marriage prospect.
Her foster parents, grimly determined to have her settled, secretly approached a matrimonial agency to locate a candidate for her hand. They found one in Charles Lafarge and presented him to Marie as a family acquaintance. The fact that he was a widower was not mentioned. Marie was told only that he owned profitable ironworks and a magnificent château called Le Glandier in the provinces. Although repelled by Charles, whose manners and appearance were unfortunate, she was dazzled by detailed drawings of his exquisite château. Passionately encouraged by her aunt, Marie married Charles and traveled with him to his home.
She was shocked to discover that Le Glandier was actually a festering pile of crumbling stone—cold, gray, grim, and forbidding. Worse, it was inhabited by Charles’s mother, who was also cold, gray, grim, and forbidding. A few other relatives and hangerson lived on the premises, including Anna Brun, who had drawn the imaginative pictures of the mythical Le Glandier, and who seemed to have a romantic interest in Charles and resented his marriage. Armies of resident rodents roamed freely through the rooms, competing for sustenance with the assorted poultry that nes
ted, clucking comfortably, in the kitchen. Marie, in hysterics, locked herself in her room.
She eventually emerged, only to discover over the next few weeks that Charles’s business was bankrupt, that he was a widower who had spent his deceased wife’s fortune, and that he evidently had married Marie for her dowry, which, while modest by Paris standards, had marvelous appeal in the provinces. Marie appeared to adjust to this situation calmly and busily went about improving the household. She ordered new curtains, joined a library, cooked complicated dishes involving truffles, and, no doubt in the interests of hygiene, wrote to the local doctor, “I am overrun with rats. Will you trust me with a little arsenic?”
She seemed to have acquired affection for Charles. When he went to Paris on business, she arranged for cake to be sent to him. Unfortunately, he became seriously ill after a small bite and returned to Le Glandier so that his new wife could nurse him. She was attentive, bringing him all sorts of soothing drinks and soups. Still, he worsened. Anna Brun claimed she had seen Marie stirring a white powder that she carried in a small malachite box into Charles’s food and drink. Anna discreetly gathered samples of the food and hid them.
After two weeks of increasing agony, Charles died. Anna produced the samples she had hidden. The local doctors tested them and the contents of the malachite box with the primitive method of exposing them to heat. They gave off a strong smell of garlic and turned yellow. On this basis, the doctors declared that they contained arsenic. Tests on the dead man’s stomach contents gave similar results, so Marie was charged with the murder of her husband.
Her aunt, no doubt worried about the family reputation, as the case was widely covered in the press, hired, at enormous expense, Maître Paillet, a lawyer of great reputation and skill, to defend Marie. He immediately attacked the tests as inadequate. As a friend of Orfila, Paillet was aware of recent advances in poison detection, and at Orfila’s suggestion, he insisted that the new Marsh test be performed. Apothecaries from Limoges were instructed by the court to do so. Unwilling to admit their inexperience, they attempted the procedure and finally reported that no arsenic could be detected by the Marsh test. Marie’s many supporters were jubilant.
The prosecutor countered by insisting that the famous Orfila himself be asked to repeat the Marsh test. The defense was forced to agree. Orfila arrived from Paris and tested the specimens in full view of the local experimenters, working all through the night. The following afternoon, he testified to a hushed courtroom that he had found arsenic in all of the samples. He explained that the Marsh test was delicate and required administration by an expert.
Marie Lafarge was found guilty and was sentenced to death, which was reduced to life imprisonment at hard labor; the hard labor was subsequently eliminated. She served ten years in a suite of cells, writing her memoirs and corresponding with sympathetic supporters, among them the writer Alexandre Dumas ( père). She was released by Napoleon III and died of tuberculosis shortly after her release, claiming her innocence to the end.
If Marie’s attorney had rested his case less on the Marsh test and more on the fact that the physical evidence had been collected by Anna Brun, a clearly prejudiced party with a motive of her own, the result might have been different.
Whatever the legal issues, the Lafarge case made clear the fact that toxicology was complex and required skill and experience as well as theoretical knowledge. It also opened the door for the great poison trials of the Victorian era.
By 1842, a simpler method of testing for arsenic had been developed by Hugo Reinsch of Germany. The new science of toxicology seemed sure to grow in importance. And then came a devastating setback, when Dr. Thomas Smethurst was tried at the Old Bailey for the arsenic murder of Isabella Bankes.
“When a doctor does go wrong he is the first of criminals. He has nerve and he has knowledge,” says Sherlock Holmes in “The Adventure of the Speckled Band.” And his observation is borne out by the number of Victorian and Edwardian poisoners with medical training. Pritchard, Cream, Palmer, Warder, Waite, and Crippen—all murderous doctors whose names conjure nightmares.
But the Smethurst case was unique. It was not simply a matter of a rogue physician poisoning a trusting soul. It was as well the case of an eminent medical expert whose careless error damaged the public’s trust in the accuracy of scientific testimony.
In 1858, when Dr. Smethurst was in his fifties and his wife was almost twenty years older, they arrived by carriage at the London suburb of Bayswater and rented lodgings in a boardinghouse. Smethurst specialized in hydrotherapy, a Victorian medical therapy that involved the forceful application of water to every possible orifice in the human body. He told the landlady that he was considering opening a practice in Bayswater and wished to familiarize himself with the area.
Isabella Bankes, a fellow tenant, was forty-two, possessed of a bit of charm, a moderate amount of money, and a medical history of occasional digestive complaints. She was happy to confide her problems to a doctor. He seemed delighted to discuss her symptoms. As their clearly intimate chats grew lengthy, the landlady grew uneasy, in spite of the fact that Mrs. Smethurst seemed to view the matter with an odd detachment.
Finally, the indignant landlady asked Miss Bankes to leave. She did, but accompanied by Dr. Smethurst. They were married in a religious although bigamous ceremony at Battersea Church and then moved to Richmond to enjoy domestic bliss.
It was not to be. Shortly after the “wedding,” Isabella became ill, suffering from violent diarrhea and vomiting. When a few days of treatment by her “husband” did not help, a local practitioner, Dr. Julius, was sent for. The patient was given chalk to drink in an effort to control her symptoms, but she grew worse. Another opinion was sought. And another. The illness intensified. A lawyer was called, and Isabella signed a will, leaving all of her money to “my sincere and beloved friend, Thomas Smethurst.”
Dr. Julius and his partner, suspecting an irritant poison, removed the contents of Isabella’s chamber pot and took it to the laboratory of Alfred Swaine Taylor, the eminent pathologist who also practiced toxicology. He undertook to examine the specimen using the elegantly simple Reinsch method.
The suspect material was mixed with hydrochloric acid and heated. A copper mesh was then inserted in the solution. If arsenic was present, it would appear as a dark gray coating on the copper. Taylor reported that the test on Isabella’s specimen was positive for arsenic.
Smethurst was usually the person who had given food and drink to Isabella, and he rarely left her side. In view of these suspicious circumstances, he was arrested. He tearfully told the examining magistrates that his wife’s illness made it a hardship for him to be separated from her and that she was in sore need of his care. He was promptly released.
Isabella Bankes died the next day.
Smethurst was charged with murder. The trial, in July 1859, attracted great attention as one that would hang almost completely on scientific evidence. The medical testimony was unexpected. At autopsy, the deceased woman was found to be five to seven weeks pregnant. Her intestines appeared to be greatly inflamed, consistent with arsenic poisoning. But an attempt to demonstrate arsenic in her internal organs was unsuccessful. How was it possible for arsenic to be clearly present before death and disappear after it?
Further experiments yielded a distressing fact. When Taylor initially carried out the Reinsch procedure, he had not considered testing the copper mesh before inserting it into the slurry of acid and fecal matter. The copper, which had been used many times before, had been contaminated with arsenic. Dr. Taylor had fatally damaged the experiment with his own reagent.
Several expert witnesses for the defense argued that the cause of death was a form of dysentery, aggravated by a first pregnancy in a lady of mature years, but the judge’s summation was damning. After forty minutes of deliberation, a verdict of guilty was delivered and a death sentence decreed.
There was an immediate outcry from the medical community, which argued that the scientif
ic facts did not justify the verdict. A lengthy and emotional plea for mercy was made to Queen Victoria by the first and only legal Mrs. Smethurst, who had evidently awakened from her torpor. The home secretary gathered the facts, considered them carefully, and overturned the verdict.
As Dr. Smethurst left the jail a free man, he was immediately rearrested on charges of bigamy and sentenced to a year in prison. Thus, with one stroke the government met the highest ethical standards of Anglo-Saxon jurisprudence and at the same time fulfilled the deepest needs of British middle-class morality.
When he was finally released from prison, Dr. Smethurst (clearly a man ahead of his time) sued for Miss Bankes’s estate. He won the case, pocketed the money, and disappeared from public view, some say in the cheerful company of Mrs. Smethurst. The lay public as well as the scientific community reacted with grave mistrust of “expert” witnesses, and the entire field of medical jurisprudence was viewed as tainted for years.
Arthur Conan Doyle was born in the same year as the Smethurst trial. Decades later, when he was a medical student, the reverberations were still being felt. Joseph Bell, the physician who was Conan Doyle’s teacher, mentor, and model for the character of Sherlock Holmes, was deeply ambivalent about the forensic world and is said to have hidden his participation in a number of cases. Conan Doyle had met Bell in 1876 and was enormously impressed by the older man’s incisive personality and deductive powers.
As a medical student, Doyle must have been a close observer of the Chantrelle case of 1878, which some historians believe Dr. Bell took part in solving. Eugene Marie Chantrelle was an immigrant from France to Edinburgh, Scotland. He had spent some time in medical school in Nantes, France, but did not complete his degree. In Scotland, he taught French with reasonable success. He formed a romantic relationship with a student, Elizabeth Dyer, and married her when she was just sixteen. A child was born to them two months later.
