Arsenic has been a favored toxin with which to dispatch people for centuries. Indeed, the very word "arsenic" elicits a fearful response in most people. And, yet, this lethal substance has also served as a medicine, used in the Middle Ages to help combat a number of maladies. But it's as a sinister poison that arsenic has earned its malevolent reputation, and history has recorded numerous instances where the "king of poisons" has been administered to fatal effect.
So, who discovered arsenic, and how has it been used to commit murder? Click through and follow the poisonous history of arsenic.