A collection of fascinating scientific stories, this book sheds light on the origins of controversial ideas throughout the history of science. Discussing discoveries and mistakes, and the confusion between the two, this book explains how the belief in Martians is due to the astronomic observations of a Jesuit priest, tells readers the incredible story of N-rays, and describes the bizarre 17th-century practice of using blood transfusions from dogs and lambs to treat mental illnesses. These historical anecdotes demonstrate how even the most brilliant minds can sometimes be mistaken, and how even the most egregious of scientific errors can still lead to revolutionary breakthroughs.