Ewing's theory of the construction of a magnetic atom separates the atom into two portions: (a) the Weber element, possessing constant magnetic moment and capable of turning in response to an applied magnetic field; and (b) an outer (or inner) group of fixed “magnets” (i.e. electrons moving in orbits), which have like poles all directed towards the centre of the atom. Owing to the want of symmetry of the elements composing the group or shell, there are several magnetic fields, each of different direction, acting in the neighbourhood of the Weber element, and the direction of each of these represents a position of stability of the Weber element.