This can easily be seen by considering the following. Unlike the levity-gravity polarity, in which one pole is peripheral and the other point-centred, both Doles of the electrical polarity are point-centred; both are located in physical space, and thereby determine a definite direction within this space. It is this direction which remains a characteristic of both the magnetic and the thermal fields. The direction of the thermal field as much as that of the magnetic is determined by its having as its axis the conductor joining the poles of the antecedent electrical field. Both fields supplement each other in that the thermal radiation forms the radii which belong to the circular magnetic lines-of-force surrounding the conductor.3 Our picture of the process which is commonly called an electric current is now sufficiently complete to allow us to make a positive statement concerning the direction in which it takes place. Let us once more sum up: In order that this process may occur, there must be present in an electrically excited part of space a body which does not suffer the particular polarization of space bound up with such a field. As a result, the electrical field disappears, and in place of it appear a thermal field and a magnetic field, both having as their axis the line connecting the two poles. Each of them spreads out in a direction at right angles to this fine. Obviously, therefore, it is in this radial direction that the transformation of the electrical into the thermo-magnetic condition of space must take place. This picture of the electro-thermo-magnetic happening, as regards its direction, is in complete accord with the result obtained (as indicated earlier) by the mathematical treatment of high-frequency phenomena. Once more we see that quite primitive observations, when properly read, lead to findings for which scientific thought had to wait until they were forced on it by the progress of experimental technique - as even then science was left without a uniformly valid picture of the dynamic behaviour of electricity. Further, we can now see that when we apply electricity to practical purposes, we are in fact seldom using electricity itself, but other forces (that is, other combinations of gravity and levity) which we make effective by making electricity disappear. The same is true of most of the methods of measuring electricity. As a rule, the force which sets the instrument in motion is not electricity but another force (magnetism, heat, etc.) which appears in the place of the vanishing electricity. Thus the so-called intensity of an electric current is actually the intensity with which the electricity in question disappears! Electricity serves us in our machines in the same way that food serves a living organism: it gets itself digested, and what matters is the resulting secondary product.