H. Alfven, in recent papers [Stockholm, Vet‐Ak. Handl., 18, No. 3 (1939) and No. 9 (1940)], attributes magnetic storms and auroras to a stream of ions and electrons emitted from the Sun, the electrons with energies about 108 volts and the ions with smaller energies. The theory differs from Chapman and Ferraro's theory of magnetic storms by taking into account the magnetic field of the Sun and supposing that the motion of any individual particle is hardly affected by the magnetic field due to the motion of other particles.The outward motion of the stream from Sun to Earth is explained as due, not to the original outward velocities of the particles, but to electromagnetic effects. Alfven divides the motion of a particle in the Sun's magnetic field into four parts (see Note 1 on page 212):