G. E. M. Jauncey and the Compton Effect

In late 1922 Arthur Holly Compton (1892–1962) discovered that an X-ray quantum of radiation undergoes a discrete change in wavelength when it experiences a billiard-ball collision with a single atomic electron, a phenomenon that became known as the Compton effect and for which he shared the Nobel Prize in Physics for 1927. But for more than five years before he made his discovery, Compton had analyzed X-ray scattering in terms of classical electrodynamics. I suggest that his colleague at Washington University in St. Louis, G. E. M. Jauncey (1888–1947), helped materially to persuade him to embrace the quantum interpretation of his X-ray scattering experiments.