Birkeland (19) supposes the ultimate cause to be cathode rays emanating from the sun; C. Nordmann (24) replaces the cathode rays by Hertzian waves; while Svante Arrhenius (25) believes that negatively charged particles are driven through the sun's atmosphere by the Maxwell-Bartoli repulsion of light and reach the earth's atmosphere.
On either Birkeland's or Nordmann's theory, the electric impulse from the sun acts indirectly by creating secondary cathode rays in the earth's atmosphere, or ionizing it so that discharges due to natural differences of potential are immensely facilitated.
Next april's wpt has been the of cathode rays in darkness produced.
Next april 's wpt has been the of cathode rays in darkness produced.
