This law was proved by Coulomb by means of an instrument known as Coulomb's Torsion Balance, and I must refer the reader to any work on electricity for a full establishment of this law. Suffice to say, that it has been experimentally demonstrated that the law holds good in relation to the phenomena of electricity; and, wherever we get the two kinds of electricity present in any medium or conductor, owing to the polarization of its particles, there we have this law operating in relation to the intensity of the repulsions of the two bodies directly concerned.

We have already learned that the sun is an electrified body, and from that hypothesis we have arrived at the conclusion that the earth and all the other planets are electrified bodies. This being so, it naturally follows that the intensity of the centrifugal force between any two of these bodies, as the sun and the earth for example, or the sun and Jupiter, is subject to the law of inverse squares; and that the repulsion of the sun and the earth for each other is always regulated by their distance, being inversely as the squares of the distance between them.

Thus, if the distance between the sun and any planet is reduced to one-half, which is an exaggerated view, the intensity of the centrifugal force is increased four times; if the distance be doubled the force is reduced to four times its former intensity, and so on.

Whatever the distance may be between the sun and any of the planets, if that distance be increased or decreased, then the intensity of the centrifugal force due to electric waves is increased or decreased in accordance with the law of inverse squares. This agrees with the centripetal law of Gravitation, as the Attraction of Gravitation is also subject to the same law of inverse squares, and, as we have seen ([Art. 83]), its path coincides with the path of centrifugal force, as it pursues the path represented by the straight lines joining the two bodies.

So that, whenever, and wherever, at any point in space in relation to the central body, the sun, the intensity of the attractive force is increased according to the law of inverse squares by the distance from the central body being diminished, at exactly the same time and in exactly the same manner, the repulsive force due to aetherial electric waves is also increased. If the attractive force is doubled, then the repulsive force is doubled. If the attractive force is halved, the repulsive force is halved. If the attractive force is lessened gradually, then the repulsive force is lessened gradually; and if quickly, by the quicker motion of the planet through space, then the repulsive motion is also increased with a quicker motion.

Further, like the repulsive power of light and heat, the repulsive power of electricity takes exactly the same path as the attractive power of Gravitation.

Thus we learn that the sun is the centre of two forces: first, a centrifugal force due to the pressure of the aetherial medium which is ever directed away from the sun, and which may either be produced by electric or thermal or light waves; and second, it is the centre of a centripetal force known as the Law of Gravity, whatever that may be due to. Further, the centrifugal force is also subject to the same law of intensity as the centripetal force, and moreover takes exactly the same path which the centripetal force takes.

So that we have only to prove that they both agree in another particular, viz. that their power is regulated by the product of their masses, and then we shall have discovered a real physical force, which is the exact complement and counterpart of the centripetal force due to gravity.

Art. 85. Second Law of Electricity. (Product of Masses.)--We have now to prove that the centrifugal force exerted by any electrified body operates upon another electrified body in the same proportion and with exactly the same force which governs the centripetal force. From [Art. 21] we learn that the centripetal force which is exerted by one body upon another is equal to the product of their masses. In order, therefore, for any centrifugal force to be the exact counterpart of that force, it too must be subject to the same law of proportion, that is, the repulsive force between any two bodies must be equal to the product of their masses.

We have shown that there is a repulsive force exerted by the Aether from the phenomena of heat, light, and electricity, and that that repulsive force or energy fulfils every condition required by a centrifugal force or motion, with the exception of the part referring to the fact that such a force must be proportionate to the product of their masses. What we were unable to accomplish, however, from the phenomena of heat or light we are now able to accomplish from the phenomena of electricity