Mass poisoner dies in prison

March 7, 1910 San Francisco, California Cordelia Botkin (pictured) dies in prison Botkin had been involved in an affair with John Dunning for three years before his wife, Mary, discovered the infidelity. Mary took their daughter and moved to Dover, Delaware, roughly 2,900 miles (4,670 km) away. John and Botkin continued their affair for some…