There are some interesting phenomena connected with the Zeeman effect which are more easily observed than the effect itself.
Professor Zeeman, of Holland, produced experimental proof of Lorentz's theory.
Dutch physicist whose study of light sources in a magnetic field resulted in his discovery and explanation of the Zeeman effect. For this work he shared with Hendrik Lorentz the 1902 Nobel Prize for physics. He also studied the absorption and motion of electricity in fluids and magnetic fields on the surface of the Sun.