Abstract
Crookes' discharge tube having a small inner paddle wheel which is rotatable along a railway is customary used as an impressive apparatus to demonstrate the impact force of cathode ray particles against the paddle wheel. However, since J. J. Thomson suggested that the rotation of the paddle wheel cannot be the direct result of the impact of cathode ray particles but is caused by the so-called "radiometer effect", several authors studied this problem closely and confirmed that J. J. Thomson's interpretation is reasonable. In this paper, the review of these studies is presented and the reason why the fallacious explanation of the impact effect of cathode ray particles has been widely accepted in Japan is also discussed.
