Mary Ann Geering poisoned her husband and two of her sons with arsenic over five months at Guestling in East Sussex, and was hanged at Lewes on August 21, 1849.
She was born Mary Ann Plumb in 1800, the eldest of five children, and lived in the parish of Westfield. Her husband Richard Geering, fifty-six, died in September 1848. Her sons George, twenty-one, and James, twenty-six, died in the months that followed. A fourth member of the household fell ill and survived, and it was that survival that prompted the examination which found arsenic and mercury.
She was arrested on April 28, 1849, convicted, and executed publicly at Lewes before a crowd reported in the thousands. She was known afterwards as the Guestling murderess.