There was something about the middle-aged housekeeper that was bound to attract the attention of the police eventually. Everyone she came into contact with seemed to die mysteriously.

She was Catherine Wilson, who had first been housekeeper to retired sea captain Peter Mawer at his home in Boston, Lincolnshire. He was so pleased with her work that he made a will leaving all her money to her. A few weeks later he died of colchicum poisoning.

The drug was often prescribed in small doses to alleviate gout, but it is lethal if taken to excess. Because Captain Mawer had gout and had been taking it, his housekeeper did not come under suspicion.

Catherine next headed for London with a man named Dixon, who she described as her husband. They took lodgings at the Bloomsbury home of Mrs. Maria Soames, 48, a rich widow. Dixon earned very little, and when Catherine got behind with the rent it seemed to her that one way out of her difficulty would be to dispose of the landlady.

First, though, Dixon must be dealt with. He suddenly became ill – two days later he was dead. The doctor refused a death certificate without a post-mortem, but when the body was opened the presence of colchicum poison was completely missed.

Now it was Mrs. Soames’s turn. She had just received a small legacy, she said, and to congratulate her Catherine offered her a nice cup of tea. After that the landlady was never the same again. Four days later she died in agony, and when the same doctor who had been called to Mr. Dixon arrived at the house he found Catherine standing at the window weeping.

The doctor wasn’t suspicious, and the post-mortem again failed to identify the poison.

Catherine moved on again, to Brixton, where once again she got behind with the rent. A friend, Mrs. Atkinson, had come to stay with her, and Mrs. Atkinson had plenty of money. On the fourth day of her visit Mr. Atkinson received a telegram from Catherine informing him that his wife had died suddenly, after someone had robbed her of all her money.

Catherine’s next employer was Mrs. Sarah Carnell, who also made out a will in her favour. She became ill, took some “medicine” from Catherine, and, when she spat it out in disgust, watched in horror as it burned a hole through the bed sheets. Catherine fled, but was arrested six weeks later, tried at the Old Bailey for attempted murder and, amazingly, acquitted.

But by now the police had the measure of her. They had already investigated the death of an elderly Boston woman who had died in circumstances suggesting poisoning, from whom Catherine had benefited by more than £100. As the travelling housekeeper left the Old Bailey after her acquittal they arrested her for the murder of her former landlady, Maria Soames.

This time Catherine was found guilty. She was hanged at Newgate on Monday, October 20th, 1862, before a crowd of some 25,000, and became the last woman to be publicly hanged in the capital.