N-Rays: A New Form of Radiation Emitted by Living Organisms and Metals

In 1903, French physicist René Blondlot announced the discovery of N-rays, a purported new form of electromagnetic radiation that seemed to emanate from the sun, certain metals, and living organisms. The discovery was announced in prestigious journals, and Britannica duly recorded it as a legitimate scientific advance. Other researchers began publishing confirmations, and the phenomenon seemed to be establishing itself as a genuine discovery. However, some physicists couldn't reproduce Blondlot's results, and scepticism grew. The decisive blow came when physicist Robert Wood visited Blondlot's laboratory and, during an experiment, secretly removed crucial apparatus, yet Blondlot continued to report detecting N-rays that shouldn't have been present. The phenomenon was entirely subjective, existing only in the observers' expectations. N-rays were a collective hallucination, a product of confirmation bias and inadequate experimental controls. By 1905, the scientific community abandoned N-rays as illusory, and Britannica's entries erased or footnoted the brief episode. N-rays became a cautionary tale in the history of science: even elite researchers can fall victim to systematic bias when expectations are strong and measurements ambiguous. The episode vindicated the importance of reproducibility and blind experimentation.