PROF. NICHOLSON has recently (Phil. Mag., vol. 50, p. 650, 1925) pointed out the importance of investigating the effect of a magnetic field on the so-called “doublet bands” of helium. He gives reasons ...
THE discovery, announced by J. Stark in NATURE of December 4, 1913, that when hydrogen in a state of luminescence is placed in an electric field of suitable strength and direction, the spectral lines ...