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Mary Ann Cotton: The Black Widow

Mary Ann Cotton of County Durham is considered to have been the UK’s first serial killer.

She was called ‘the black widow’. How did she succeed in killing her victims? Arsenic.

Mary Ann poisoned 3 of her husbands and 16 of her children for their life insurance money, as well as two lodgers that died under her roof.

Cotton knew what she was doing. She poisoned her victims with arsenic which had the same symptoms as gastric fever, which some of her children did actually succumb to. Before 1830 arsenic poisoning was challenging to detect until a test was developed for it. Arsenic was commonly used in the Victorian era, so it was easy for Mary Ann to get her hands on it. It was used in children’s toys and wallpapers. However, 21 people were reported to have died in the hands of Cotton so this was no accident.

Arsenic poisoning occurs after the ingestion or inhalation of high levels of arsenic. It is a white-grey carcinogen. It is odourless and tasteless meaning that the victim would not suspect it in an innocent-looking cup of tea. The arsenic act was introduced in 1851 due to increased public concern over accidental and deliberate arsenic poisonings. This, however, did not prevent the sale of arsenic. One could purchase arsenic from a pharmacist if one could justify it. It was commonly used in making a type of soap and for getting rid of bed bugs, reasons that Mary Ann Cotton used herself. She is also believed to have used fake names to purchase even more than what she would have been allowed.

The symptoms of arsenic poisoning include abdominal pain, nausea, and diarrhoea. These symptoms are identical to gastric fever (gastroenteritis) which was very prevalent in Victorian times. This is how Cotton got away with so many of her previous murders.

She was only officially convicted of the murder of her stepson Charles. Her being responsible for her stepson prevented Mary Ann from marrying again and she is quoted to have said “I won’t be troubled long”. Shortly after this, Charles died. As well as that, Cotton’s first visit after Charles’ death was not to the doctors but the insurance office. Here she discovered that she would not be able to collect the insurance policy until a death certificate was issued.

The authorities were notified of what Cotton said and they became suspicious regarding Charles’ death. His body was examined, and arsenic was found in his stomach. Following this, the body of a former lover and Charles’ siblings were exhumed, and they were all determined to have died from arsenic poisoning. Mary Ann never confessed to any of the deaths, but all the signs lead to her. The exact number of her victims is unknown, but it is believed to be at least 21 people.

On March 24th, 1873, Mary Ann Cotton, the UK’s first reported serial killer was sentenced to hang for her crimes. She died without dignity. The noose was improperly set up and she was recorded to have been writhing in the noose for at least three minutes. She should have died instantly from breaking her neck when hanged however she died from asphyxiation. The tight rope around her neck strangled her. This appalled the witnesses as they expected to see a quick death. A lot were anguished by this and felt that she did not deserve this punishment especially as she had only given birth to her last child days before her death.

The Black Widow knew what she was doing and was very careful in her type of poison.

Mimicking a prevalent illness allowed Mary Ann Cotton to get away with murder one too many times.

Want to learn more about the effects of toxic substances on the body? Get your tickets for The Post Mortem Live here - coming to a town near you!


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