As already indicated, Lorentz was of the opinion that the light waves were themselves electric currents, and whether this is the actual fact or not, certainly it is true that the electro-magnetic theory of light is no mere fable or myth, but that it ranks as one of the most advanced and correct hypotheses in regard to light that has ever been given to the world. According to that theory, which we shall look at subsequently, we find that the aetherial medium is not only the medium for the light waves, but that it is also the medium which conveys and carries the electric currents through space, and even through all matter. Further, from that theory we shall have good reasons for assuming that the aetherial light waves are either themselves electric currents, or closely identified with them, in the same way that the light waves are identified with heat waves. If these facts should be found to hold good relative to the identity of aetherial light waves and the aetherial electric waves, then it can very readily be seen that such a hypothesis gives added weight to the repulsive power of light. One of the very commonest facts regarding electricity and its currents is, that wherever we get electricity, we not only get attraction, but there is always associated with that attractive force a repulsive force, which is equal in amount to the attractive force. So that if, wherever we get electric currents, we find associated with those currents a repulsive force, then, in view of the electro-magnetic theory of light, it should also follow that on that hypothesis we ought also to find a repulsive power in light. From the dynamical aspect of light on the bases of facts given to the world by such men as Professor Stokes, Clerk Maxwell, Lord Kelvin, and Professor Lebedew, we are compelled, therefore, to come to the conclusion that light does possess such a repulsive force, such force being due to the dynamical action of the aetherial light waves.