N-ray

N-rays (or N Rays) were a supposed form of radiation, described by French physicist Prosper-René Blondlot in 1903. Following the discovery of X-rays by Wilhelm Conrad Röntgen, there was significant interest and competition in the scientific community to discover new forms of radiation. Blondlot, working at the University of Nancy in France, claimed to have discovered N-rays emanating from most substances, including the human body. However, subsequent investigations revealed that N-rays were the result of experimental error and psychological bias, leading to their classification as a classic example of a scientific error and pathological science.

Discovery and Investigation

Blondlot began his experiments on N-rays in 1901, influenced by the recent discovery of X-rays and other forms of radiation such as radioactivity discovered by Henri Becquerel and the Curies. He reported that N-rays could enhance the brightness of an electric spark, which could only be observed in a very dark room and with a specially adjusted vision. Blondlot and his colleagues published numerous papers on N-rays, claiming they had been observed by over a hundred scientists.

The scientific community outside France was skeptical of these claims, primarily because no one was able to replicate Blondlot's findings. In 1904, American physicist Robert W. Wood visited Blondlot's laboratory on behalf of the journal Nature to observe the experiments. Wood secretly removed an essential prism from the experimental apparatus, which supposedly was crucial for the detection of N-rays. Blondlot and his assistants, however, still claimed to see the rays, unaware of Wood's modification. This incident, along with Wood's subsequent report, discredited the existence of N-rays and demonstrated the influence of expectation bias on experimental observations.

Aftermath

The N-ray affair had a significant impact on Blondlot's career and is often cited as a cautionary tale about the importance of skepticism and replication in scientific research. It highlighted the susceptibility of scientists to confirmation bias and the need for independent verification of experimental results. The incident also underscored the role of peer review and the importance of critical evaluation by the scientific community.

Despite the controversy, Blondlot continued to work in physics until his retirement, although he never regained his former prominence. The N-ray episode is a reminder of the pitfalls that can ensnare even skilled and well-intentioned scientists.

See Also

• Scientific method
• Pseudoscience
• List of experimental errors