In the winter of 1855 and 1856 a Staffordshire surgeon named William Palmer was the most discussed man in England, and the chemistry that sent him to the gallows did not detect the poison it was supposed to prove. Alfred Swaine Taylor, the toxicologist at Guy’s Hospital whom Katherine D. Watson describes as the most respected in the country and an unofficial adviser to the Crown, examined the organs of John Parsons Cook and reported no strychnine. He concluded all the same that strychnine had killed Cook, and he became the prosecution’s chief witness. James R. Voelkel, writing for the Science History Institute, notes that the conviction rested on that reasoning from the course of the illness and not on chemical proof.
The age that followed, roughly the years from 1837 to 1914, produced a run of poisoning trials in four countries, and they have more in common than their method. Most depended on a household purchase that nobody questioned. Many turned on a death that a doctor had certified as natural. Insurance money hovered over most of them. And in each, a local newspaper, a coroner’s jury or a crowd outside a prison had formed its verdict before the court did. Nine of these cases show the machinery that surrounded them. Only some ended in a conviction for more than one death, and in several the larger totals attached to a name come from suspicion, inquests and later writers, not from a court.
Palmer was born on August 6, 1824, and practiced in his native Rugeley. According to Voelkel he meant to settle there as a country doctor, but he gave most of his practice up for horse racing and betting and fell deep into debt. Watson describes a man run down by moneylenders.
A number of sudden deaths clustered around him, and none was questioned when it happened. Watson lists his mother-in-law in 1849, a racing companion named Leonard Bladen, to whom he owed eight hundred pounds, in 1850, and four infant children between 1851 and 1854. No inquest verdict was ever returned against him in any of those cases and he was never charged. Watson’s point is that they looked different only afterward: once Cook was dead, it became clear in hindsight that his was not the first sudden death around Palmer.
Insurance came into the later cases. Voelkel records that Palmer took out three policies on his wife’s life totaling thirteen thousand pounds, and that in January 1855 he insured his brother Walter for the same sum. Anne Palmer died on September 29, 1854, and Walter on August 16, 1855. The insurers grew suspicious, refused to pay and engaged a private detective. Cambridge University Library’s account of the case says Palmer was suspected of poisoning his wife, his brother and possibly four young children to collect.
Cook was 28, a wealthy racing enthusiast who co-owned horses with him. In November 1855 he won a large sum, fell ill and died on November 21, with Palmer in attendance. The inquest opened on November 29, and on December 15 the jury returned a verdict of wilful murder against Palmer. Watson reports that his solicitor later swore that more than thirty newspapers had sent reporters to the inquests. Two further inquests followed, after the bodies of Anne and Walter Palmer were taken up for re-examination on December 22, 1855. Taylor attributed Anne’s death to antimony, and suspected another poison in Walter’s that was never detected. Juries returned verdicts of wilful murder against Palmer on January 12 and January 23, 1856. Those were findings of coroner’s juries. Neither case went to trial.
Feeling ran high enough that the law itself bent. Watson quotes a report that the population had divided into Palmerites and Anti-Palmerites, and she notes that the Illustrated Times called the case the crime of the age. On January 26, 1856, Palmer and his solicitor, John Smith, swore affidavits that no fair trial could be had in Staffordshire or anywhere in the Midlands. Smith cited the press coverage and swore that one juror had helped to gather evidence against Palmer. On January 31 the Court of Queen’s Bench, with Lord Chief Justice Campbell presiding, ordered the trial moved to the Central Criminal Court in London.
The statute fixed that court’s reach, however, and a new law was needed. In the Commons committee on March 10, 1856, Sir Alexander Cockburn, the Attorney General, answered members who feared the bill could be turned against persons accused of treason by saying that Palmer had himself asked for removal, because the state of public feeling at Stafford left him no hope of an impartial hearing. Two Staffordshire members denied that he could not be fairly tried in his own county. The bill passed without amendment and received royal assent on April 11, 1856, as the Central Criminal Court Act. It became known as Palmer’s Act.
The trial opened on May 14 and turned largely on rival medical experts. The defense argued that Cook could have died of natural causes. Contemporaries complained that the judges were biased against the prisoner, that Taylor and the Crown’s experts were given unfair advantages, and that the press had made a fair hearing impossible. On May 27 the jury convicted Palmer of the wilful murder of Cook. He was hanged at Stafford on June 14, 1856, before a large crowd. He was never tried for any other death.
Mary Ann Cotton was hanged at Durham County Gaol on March 24, 1873, for the murder of her stepson, Charles Edward Cotton, who died at West Auckland in the summer of 1872. The first inquest returned a verdict of natural causes. The doctor who had carried out the post-mortem examination did not leave it there. He ran further tests on the organs, and they showed arsenic. She was arrested in July 1872.
The deaths around her ran back two decades. By the time of her arrest she had been married four times, the fourth while her third husband was still alive, and she had moved between pit villages and shipbuilding towns across the North East. Durham University Library’s note on her life says she married William Mowbray at 20, that four of their children died before the family came back to County Durham, that three more were born at Sunderland and died, and that Mowbray died too. She collected 35 pounds in insurance. The library itself points out that other accounts disagree with it on where the Mowbrays lived and on how many children there were, and no record of how any of those children died has been reported. Beamish, the open-air museum of the North East, says she may have had as many as 21 victims, including three of her four husbands and 11 of her 13 children. Almost all of that rests on suspicion and later research.
What the court dealt with was narrower. After her arrest the bodies of Joseph Nattrass, Frederick Cotton junior and Robert Robson Cotton were examined, and Durham University Library says arsenic was reported in each. The chemical work was done in Leeds by an analyst, Thomas Scattergood, whose casebook now sits in the University of Leeds Special Collections. It records the West Auckland cases on pages 179 to 206, in entries from July 26 to October 16, 1872. She was charged with four murders, denied them, and was tried only for Charles’s.
Why so many deaths passed unremarked is a question of period medicine. David Wilson calls arsenic the poison of choice of the 1870s and notes that its effects could be taken for gastric fever, cholera or typhoid. Several of the earlier deaths linked to her were certified at the time as natural illness. The jury at the Durham Assizes deliberated 50 minutes and convicted her of the murder of Charles. The judge told her she had poisoned a child she ought to have cared for, and that poisoning was among the most deadly and detestable of crimes because of the belief, which he called a delusion, that it could be committed without discovery. The House of Commons record of March 4, 1873, shows that the conduct of the prosecution was raised in Parliament, with the Prime Minister, Gladstone, declining to intervene in a question of which law officer should lead for the Crown. W. T. Stead’s Northern Echo covered her last days in two long reports. It said she had written three times to her third husband in her final weeks, asking him to visit and organize a petition. He did not come.
Mary Ann Britland’s case shows the ordinary paper trail a poison left in the 1880s. She came from Bolton and married Thomas Britland at St Michael’s Church in Ashton-under-Lyne in 1866. According to Capital Punishment UK, the Britlands rented a house in Ashton-under-Lyne that was infested with mice. To deal with them she bought packets of a vermin powder. Because of what it contained, the law required her to sign the chemist’s poison register. The signature mattered later. When police began to look into three deaths, the register showed she had bought poison.
Her daughter Elizabeth died in March 1886 and a doctor put it down to natural causes. Capital Punishment UK observes that such deaths were unremarkable in a period of poor food hygiene and no refrigeration. A few days afterward her mother claimed on a life insurance policy worth ten pounds. Thomas Britland died next, his death diagnosed as epilepsy, and the widow claimed on his insurance too. Then a neighbor, Mary Dixon, died. With three deaths in a short time, the pattern raised suspicion. An analysis of Mary Dixon’s body detected strychnine and arsenic, and Britland was arrested.
She came to trial at the Manchester Assizes on Thursday, July 22, 1886, before Mr. Justice Cave. Her defense argued that she had no motive, since the insurance money was small and could not have made up for the loss of a husband and a daughter. The jury took some time but convicted her of murder, and she was sentenced to death. James Berry hanged her at Strangeways on Monday, August 9, 1886. She was the first woman executed there. The deaths of her daughter and husband are attributed to her by Capital Punishment UK and the local press, and no more than that.
Thomas Neill Cream, born in Glasgow in 1850 and trained as a doctor at McGill University in Montreal, was first convicted of murder in Illinois. A jury there convicted him in 1881 of poisoning Daniel Stott, a railway stationmaster, and he was sentenced to life at Joliet. According to Jill Foran, writing in Canada’s History, Stott’s body was examined after his death and the analysis reported strychnine, though Cream had blamed the pharmacists who filled the prescription. He was released on parole in 1891 and sailed for England. Foran calls the verdict one of second-degree murder; other accounts say only murder.
In Lambeth, south London, he called himself Dr. Thomas Neill. Between October 1891 and April 1892 young women in the district died of strychnine poisoning, and the way the authorities handled the first two deaths shows how a poisoner could work in plain sight.
The first to die was Ellen Donworth, 19, a laborer’s daughter who had worked pasting labels in a factory. The coroner, George Percival Wyatt, opened an inquest on October 15, 1891. A hospital physician, Dr. Thomas Kelloch, detected strychnine, and the jury on October 22 returned a verdict that she had died of strychnine and morphia poisoning but that there was no evidence to show how it was given. The police of L Division concluded she had taken it herself. Assistant Commissioner Robert Anderson at Scotland Yard accepted that view but raised the obvious question, in Dean Jobb’s account: strychnine was sold only to physicians, so how had a young woman out of work come by it? While the inquest was still open Wyatt received a letter signed "A. O’Brien, Detective," offering to name the culprit for 300,000 pounds. He took it for a prank and filed it. Jobb’s research matched its handwriting to the envelopes of letters Donworth had received.
Matilda Clover died on October 21, 1891. Her death was never investigated. A local doctor who had not come when he was called signed the certificate, giving delirium tremens and fainting as the causes as though he had attended her himself. Jobb writes that his conclusions rested on secondhand information. With a certificate of natural death, no coroner was told and no inquest held. Her death was registered as natural.
The letters came next. Written under false names, they went to prominent Londoners and threatened to accuse them of poisoning young women in Lambeth unless money was paid. The McGill News reports the targets included a society woman, a member of Parliament and a physician to the royal family. Most recipients took them to Scotland Yard, where, according to the McGill News, they were largely set aside. Jobb does not believe Cream meant to collect. He told the McGill News he thought Cream wanted people to know "what an efficient and ruthless killer he was." In the end the letters were evidence against him. He was charged in 1892 with four murders, an attempted murder and sending letters to extort money, and was tried at the Old Bailey for the murder of Matilda Clover. Mr. Justice Hawkins passed sentence of death. James Billington hanged him at Newgate on November 15, 1892.
Jobb puts the total at no fewer than ten people. A court dealt with two of them, Stott and Clover. The Lambeth deaths of Donworth, Alice Marsh and Emma Shrivell were charged but not tried.
Nancy Farrer was a young English-born nurse who had come to Ohio as a child. Over a few weeks at the end of 1851 three members of one Cincinnati household died: a mother and her two small sons. An analysis later reported arsenic in the cases of the mother, both boys and a woman from an earlier household where Farrer had nursed. She could read a little and could not write, and when asked to sign her indictment she made her mark.
The case against her was circumstantial. As the Supreme Court of Ohio later summarized the testimony, druggists said she had bought arsenic from them several times, saying it was for rats. Watt P. Marchman, the director of the Hayes Library, names three druggists and two physicians who testified to selling it to her or seeing her buy it. Two grand jury indictments were returned on January 10, 1852, and two more followed on January 15, for four deaths in all. She was tried for one, that of two-year-old James Wesley Forrest.
Her counsel, appointed by the court, included a young Cincinnati attorney named Rutherford B. Hayes. His diary entry of January 17, 1852, calls her "the poisoner of two families" and the case "the criminal case of the term." The defense argued that the evidence pointed at least as strongly toward someone else, and that she was not responsible because of imbecility. A medical lecturer, Dr. J. R. Buchanan, testified that her brain would "favor imbecility." The jury retired on a Saturday, returned on Monday to ask for further instruction on imbecility, and came back on the evening of Tuesday, March 2, 1852, with a verdict of guilty of murder in the first degree. She was sentenced to hang.
Hayes carried the case to the Supreme Court of Ohio, which on December 15, 1853, reversed the judgment because the jury had misbehaved during deliberation, and ordered a new trial. It never took place. In December 1854 a Probate Court jury declared her of unsound mind and she was placed in an asylum. By Judge Carter’s later account she walked away one day and was never traced. In law she is not a convicted murderer: the one verdict against her was set aside and the question was not put to a jury again.
Lydia Sherman was convicted at New Haven in 1872 of the second-degree murder of her third husband, Horatio N. Sherman of Derby, who had died in 1871. Her case went to the laboratory. A local physician, Dr. J. C. Beardsley, grew suspicious and ordered an examination. According to Connecticut History, he then had the deaths of Sherman’s two children and of her second husband, Dennis Hurlburt, examined as well.
The chemical work was done by George Frederick Barker, professor of physiological chemistry and toxicology at the Yale Medical School, a chair created for him in 1869. Edgar F. Smith’s memoir of Barker, reprinted by the National Academy of Sciences, calls the Sherman matter the most noted of the poison cases in which he served as an expert for the state. Barker reported arsenic in the cases of Horatio Sherman, both children and Hurlburt. What distinguished his work was how much of it there was. Smithsonian Magazine reports that he ran several kinds of arsenic test on the samples when one would have identified the poison, and the National Museum of American History’s curator Kristen Frederick-Frost told the magazine he "threw everything and the kitchen sink at the Sherman evidence." In a 2025 museum blog interview she said he used up to seven analyses per sample and every one detected arsenic.
The reason was a recent defeat for poison evidence. In 1871 Elizabeth Wharton, a Baltimore widow tried for poisoning General W. Scott Ketchum, was acquitted after her defense brought in leading experts who challenged the tests used against her as outdated. Smithsonian Magazine says Barker later acknowledged that this was why he multiplied his tests.
The jury’s verdict of second degree spared Sherman the gallows. On January 11, 1873, Judge Sanford sentenced her to life at Wethersfield State Prison. The same month she confessed to poisoning her first husband, Edward Struck, in New York in 1864, several of their children, and the two Sherman children. She denied causing Hurlburt’s death. Howard Fischer, writing in Hektoen International, says death certificates in the Struck cases gave typhoid fever, and the newspaper summary of her confession says the attending doctors put the children’s deaths down to ordinary illness. Connecticut History quotes her as admitting to "three husbands and four children," a total that does not match the newspaper summary of the same confession; the difference has never been settled. She escaped from Wethersfield in 1877, was retaken after about a week, and died in the prison on May 16, 1878. Arsenic tests Barker ran for the case are kept by the Smithsonian and went on display in Washington in 2024.
Hélène Jégado, a cook and domestic servant from Plouhinec in Brittany, was guillotined at Rennes on February 26, 1852. The assize court of Ille-et-Vilaine had convicted her on December 14, 1851, of three murders by poison, four attempted murders and 11 thefts, 18 counts in all. The Archives départementales d’Ille-et-Vilaine record the court’s own estimate that 37 people had been poisoned and 23 had died.
The great majority of those cases were never tried. French law set a ten-year limit for prosecution, and the deaths in Morbihan between 1833 and 1841 lay beyond it, although the curators of the archives' exhibition say the facts were known and weighed against her. The deaths of Louis Rabot in 1849 and Clodomir Ozanne in 1850, recent enough to be tried, were left out too, because the court seems not to have wanted to impose further examinations on the families and judged the other charges sufficient.
No one had suspected her. Cholera had struck shortly before, and the archives point out that its signs could resemble arsenic poisoning, so the deaths were put down to disease. Many doctors had private doubts and kept them to themselves. She was known as pious and devoted to the sick, and she nursed each of the dying.
The poison was arsenic, sold as rat poison. The archives say it was the substance most often used in French poisoning cases and that, until 1846, anyone could buy it. After that date it required a prescription. Before her execution she told the prison chaplain that a woman near Guern had first given her some and that she had bought more at Vannes and at a pharmacy in Rennes, but the pharmacists' registers show no such sales.
Proof had also changed. Traces of arsenic occur naturally in the body, and that made it hard to prove until 1836, when an English chemist devised what became known as the Marsh apparatus, which could measure the quantity. The Penal Code of 1810 punished poisoning with death whether or not the victim died. The archives count 12 poisoners sentenced to death by the Rennes assize court, seven of them women.
The case against her came together in 1851. After the death of a third servant, Rosalie Sarrazin, on July 1, two doctors who had attended the household raised the alarm and Jégado was arrested in Rennes that day. Faustino Malagutti, professor of chemistry at the faculty of sciences, used the Marsh apparatus on the bodies of Pérotte Macé, Rose Tessier and Rosalie Sarrazin. The bodies of Macé and Tessier were examined again on August 7, 1851, with the families' consent. The archives describe the care taken to avoid contamination, with the sample jars sealed in paper, string and red wax. Malagutti described the stains his tests produced as "indubitablement arsenicales," and at the trial he showed the jury a test tube and explained the apparatus. The case came when French forensic medicine was becoming more organized and families more willing to consent to such examinations. Her appeal to the Cour de cassation was rejected on January 16, 1852, and Louis-Napoléon Bonaparte refused a pardon on February 22.
Martha Needle lived in Richmond, Melbourne. Her husband, Henry Needle, and her three young daughters, Mabel, Elsie and May, died between 1885 and 1891. State Library Victoria says her husband’s life insurance paid 60 pounds, another 60 pounds was paid on Elsie’s death and the remaining 80 pounds on May’s. Elsie died on December 9, 1890, and her doctor remembered the illness only vaguely as measles; he told the court in 1894 that her mother had never been "inattentive or unkind." May died on August 27, 1891, and the certificate gave tubercular meningitis. Mabel’s death had been certified as a brain tumor and bronchitis. The Public Record Office Victoria says no suspicion fell on her at the time. She was pitied as a widow who had lost her family.
Suspicion came in 1894, after the death on May 15 of Louis Juncken, a brother of the man she was engaged to marry. Another Juncken brother fell ill within weeks and his doctor arranged an analysis that reported a considerable quantity of arsenic, similar to the rat poison Rough on Rats. The doctor went to the police, and Needle was arrested in Richmond and charged with attempted murder. Police then noticed how closely Louis’s death resembled those of Henry and the girls and asked to have the bodies re-examined. The State Library and the Old Treasury Building museum both report arsenic in the bodies of Louis, Henry, Elsie and May. Neither reports a finding for Mabel. The Public Record Office says only that all the bodies examined contained traces. She was charged and tried only for Louis.
At the trial in September 1894, evidence about the family deaths was heard. Samantha Battams, in her 2019 book on the case, argues that public opinion and press coverage prejudiced the proceedings before they began. Her counsel argued that spells of unconsciousness meant she could not be held responsible, and Justice Hodges rejected the plea in words the museum quotes: "The law cannot wait while philosophers, physicians and scientists settle metaphysical problems." A lawyer, Marshall Lyle, wrote to the Governor, Lord Hopetoun, on behalf of the Victorian branch of the Howard Association for the Prevention of Crime, criticizing the medical examination of her sanity. The Attorney-General, Isaac Isaacs, declined to recommend any action, saying the petition did not disclose facts that would show she was insane. She was hanged at Melbourne Gaol on October 22, 1894, still protesting her innocence. The Encyclopedia of Melbourne counts her among three women executed in a short span in 1894 and 1895 under what it calls a "get tough on crime" policy.
The last case falls in the Edwardian years and is the most disputed. Martha Rendell lived in East Perth as the de facto wife of Thomas Morris, with his children. Three of them, Annie, Olive and Arthur, died over about fifteen months, two of them certified at the time as dying of throat illness. The WA Police Historical Society says several doctors treated the children and only one doubted the cause of death. The inquiry began in April 1909 after the surviving boy, living away from the household, told police that his stepmother had killed his brother and sisters.
In September 1909 a jury convicted Rendell of the wilful murder of Arthur Morris, who was 15. Thomas Morris was tried with her and acquitted. Annie’s and Olive’s deaths were attributed to her by police and never charged. She was hanged at Fremantle Prison at 8 a.m. in October 1909; the police historical society and Traces Magazine give October 6, and the historian Anna Haebich gives October 9 and writes that it came with "unseemly haste," twenty days after the verdict.
Very little of the official record survives. Haebich wrote that, of the official sources, only the coronial inquiry papers and those of Rendell’s last days in the condemned cell remain, so that most of what is known about the trial comes from Perth’s newspapers. Crowds cheered the verdict, Haebich wrote, and applauded the death sentence. She called the poisoning theory implausible and read the Crown Prosecutor’s remark that it was "idle to speculate" about how the accused had come to use the acid as a sign that the prosecution leaned on stereotype. The police historical society, by contrast, still presents the case as the murder of all three children by Rendell. No court has re-examined the verdict.
The same few mechanisms recur across half a century and three continents. In Rennes arsenic could be bought freely until 1846, and in Ashton-under-Lyne forty years later a signature in a chemist’s register was all that stood between a householder and a packet of vermin killer. In Cincinnati it was sold to a nurse who said it was for rats, and in Melbourne the analysis likened it to the rat poison Rough on Rats. The paperwork that existed was kept, and in Britland’s case it did the work of an eyewitness.
Detection lagged behind. The doctors in Durham, Lambeth and Rennes signed certificates for illnesses that the analysts later reinterpreted, and in Lambeth a physician signed one without having attended the patient. What changed the outcome in those towns was usually a second doctor who would not let the matter drop, a surviving relative who spoke to the police, or a letter. The chemists mattered, but their standing was uneven: Taylor reported no poison in Cook and carried the Crown regardless, while Barker, a year after a Baltimore acquittal, ran every test he had.
Money appears in many of the files and is established as a motive in almost none. In Needle’s case it was never established, and Britland’s counsel argued the sum was too small to matter. And the public appears in every one: more than thirty newspapers at the Rugeley inquests, a Parliament that rewrote a statute to move a trial, a large crowd at Stafford, a crowd in Perth cheering a sentence. In several cases the number attached to the name is larger than any court’s finding. Palmer was convicted of one death, Cotton of one, Needle of one, Sherman of one, Rendell of one. Jégado’s court spoke of 37 poisoned and tried her for seven.
• August 6, 1824: William Palmer born.
• 1836: the Marsh apparatus is devised, according to the Ille-et-Vilaine archives.
• 1846: free sale of arsenic in France ends; a prescription is required.
• July 1, 1851: Hélène Jégado arrested at Rennes.
• December 1851: three deaths in a Cincinnati household; Nancy Farrer arrested on an affidavit of December 4.
• December 14, 1851: Jégado convicted on 18 counts.
• February 26, 1852: Jégado guillotined.
• March 2, 1852: Farrer convicted of first-degree murder.
• December 15, 1853: Supreme Court of Ohio reverses Farrer’s conviction.
• December 1854: Farrer declared of unsound mind.
• November 21, 1855: John Parsons Cook dies.
• April 11, 1856: the Central Criminal Court Act (Palmer’s Act) receives royal assent.
• May 27, 1856: Palmer convicted of the wilful murder of Cook.
• June 14, 1856: Palmer hanged at Stafford.
• 1872: Charles Edward Cotton dies at West Auckland; Lydia Sherman convicted at New Haven.
• January 11, 1873: Sherman sentenced to life.
• March 24, 1873: Mary Ann Cotton hanged at Durham.
• May 16, 1878: Sherman dies in Wethersfield State Prison.
• March 1886: Elizabeth Britland dies.
• July 22, 1886: Britland tried at the Manchester Assizes.
• August 9, 1886: Britland hanged at Strangeways.
• October 1891: Ellen Donworth and Matilda Clover die in Lambeth.
• November 15, 1892: Thomas Neill Cream hanged at Newgate.
• May 15, 1894: Louis Juncken dies. September 1894: Martha Needle convicted.
• October 22, 1894: Needle hanged at Melbourne Gaol.
• September 1909: Martha Rendell convicted. October 1909: hanged at Fremantle.