Students write a critique of a paper published in Science. The paper examines a historical event, the Salem witch hunts of 1692. The author strongly suggests that the afflicted girls who testified at the trials were the victims not of witchcraft but rather of ergot poisoning. Students use a reprint of the paper; the play, The Crucible by Arthur Miller; and various scientific references to learn about the life cycle and metabolism of Claviceps purpurea. This knowledge provides background for analyzing the methods used by scientists to investigate problems.