In 1903, respected physicist Prosper-Rene Blondlot of the University of Nancy announced N-rays, a new form of radiation detected by watching a dim phosphorescent screen in a pitch-black room. Roughly 120 scientists went on to confirm them in about 300 published papers. None of it was real.

This episode examines the discovery gold rush that followed X-rays, radioactivity, and the electron; the physiology of rod cells and the autokinetic effect that let the eye invent changes in brightness; and the fall 1904 visit of American physicist Robert W. Wood, who quietly pocketed an aluminum prism in the dark while Blondlot kept narrating results. It also covers the aftermath, Irving Langmuir’s concept of pathological science, and why Webster’s still defined N-rays in 1946.

• Blondlot’s credentials, including corresponding membership in the French Academy of Sciences and praise from J.J. Thomson and Henri Poincare
• Why an experiment on polarizing X-rays with a spark gap led to the claim of a new radiation named for Nancy
• The strange rules attributed to N-rays, such as emission from the human body and most substances but not from green wood
• Heinrich Rubens’s failed demonstration for Kaiser Wilhelm II and the priority disputes the Academy had to adjudicate
• Wood’s swap of a metal file for a piece of wood, his expose in Nature, and Blondlot’s belief in N-rays as late as 1926