Let us look at the a.n.a.logy which exists between the lines of force and the gravitative Aether, and we shall see that a gravitative Aether fully agrees with the conception of an electric Aether as revealed to us by the lines of force in an electric field.
As is well known, the lines of force are closer together in that part of the electric field where the intensity of the field is greatest; and the intensity of a field being greatest at the surface of an electrified body, the lines of force are therefore closer together nearest to the surface of such a body than further away.
Now according to Art. 45 Aether is gravitative, therefore the Aether nearest the surface of a body is densest, and the aetherial atoms are therefore more pressed upon than the layer immediately above it. Such a result is exactly what should happen provided that Aether has an electric basis, and that Aether is gravitative. For, in Art. 45, we have seen that because Aether is gravitative, therefore it must possess various degrees of density, being densest nearest the surface of an attracting body.
In electricity we find a similar phenomenon which corresponds to aetherial density, which is known as Electric Density, by which term is meant the amount or quant.i.ty of electricity spread over a certain area or surface. If we double the quant.i.ty of electricity on that given surface, then we double the density, and we say that the electric density is doubled, while if we halve the quant.i.ty of electricity, then we say the electric density is halved, and so on.
But this is exactly what happens in the case of aetherial density, as proved in Art. 46. We have only to picture the number of aetherial atoms being doubled on a given area, and at once the physical conception of electric density is furnished, if we remember that Aether has an electric basis as suggested by Maxwell and proved by Hertz. Thus we see at once why it is the lines of force should be closer together nearer the electrified body than farther away.
_Electric Potential._--There is another aspect of the electric field that I wish to call the reader"s attention to, and that is the Electric Potential of such a field.
Electric potential is to electricity what temperature is to heat, or pressure is to any medium of different densities. We have already seen, according to the laws of thermodynamics, that heat will flow from a higher temperature to a lower one, with the result that work is done. In the case also of water at two different levels, work can also be done by the water flowing from a higher to a lower level.
A similar thing happens in electricity; where we have two conductors or two parts of an electrical fluid at different potentials, electricity will flow from the place of higher potential, until the potentials are equalized, in the same way that the temperature of two bodies at different temperatures would be equalized by the flow of heat.
So that electric potential agrees with our conception of a gravitative Aether in that, being gravitative, it is denser in those parts nearest to the attracting body than farther away, and as the elasticity or pressure is proportionate to the density (Art. 47), therefore we learn that the electric potential of the Aether, and the thermal condition of the Aether, if I may use such a term, both agree and coincide with the density and elasticity of the Aether.
Any equipotential surface which represents a particular aetherial density, would also correspond with a particular elasticity or pressure of the Aether, while it would further correspond with a particular temperature, if such a term is applicable to the Aether.
_Equipotential Surfaces._--The fact that in an electric field there are different points at different potentials, leads us to the truth that in an electric field there are also equipotential surfaces; that is to say, there are surfaces where the electric density or the aetherial density are equal at all points on such a surface. If, for example, _E_ be an electrified body (Fig. 9), and _A_ _A"_, _B_ _B"_, represent equipotential surfaces around the body, then all the points on _A_ _A"_ would be of equal potential--that is, of equal energy, or pressure.
We have to remember that _A_ _A"_, _B_ _B"_, are sections of a sphere, so that when the body as _E_ is a sphere, then the equipotential surfaces are spheres also. This agrees with Art. 77, in which we saw that the pressure around any body due to aetherial density also possessed equipotential surfaces.
It could equally be shown that there were equipotential surfaces so far as the phenomena of heat and light are concerned, as these also are subject to the same laws. Having now very briefly considered the meaning of the Electric Field, Electric Potential, Electric Density, and Equipotential Surfaces, we are now in a position to apply these facts to our solar system, at least as far as the sun is concerned.
In the foregoing Art. we arrived at the conclusion that the sun was an electrified body, therefore, in accordance with all experiment and observation, it, too, must have an electric field. Not only must it have an electric field; but that field must possess different potentials, possessing a higher potential the nearer the field gets to the sun, and a lower potential the farther away the field is.
Further, around the sun there must also exist not imaginary but real physical lines of force which indicate the electric and magnetic forces, and which are made real by the atomic character of the Aether that surrounds it; and those lines of force would be closer together the nearer they got to the sun on account of the electric density of the electric Aether, which coincides with the density of the Aether from the gravitative standpoint. There would also be aetherial equipotential spheres, or rather oblate spheroids around the sun, as the sun is not strictly a sphere, its polar diameter being less than its equatorial diameter.
[Ill.u.s.tration: Fig: 10.]
Let us therefore endeavour to picture the sun under these conditions as the centre of our solar system. Let _S_ be the sun (Fig. 10), and the lines _A_ _A"_, _B_ _B"_, _C_ _C"_, etc. represent Equipotential Surfaces, Fig. 11 being a vertical section and Fig. 10 being an equatorial section. In Fig. 11 the sections of the equipotential surfaces would be vertical, while in Fig. 10 the sections of the equipotential surfaces would be horizontal, while the electric lines of force would be radial, as all electric radiations take place in straight lines, as we shall see was proved by Hertz, later on. We will suppose that the sun is stationary, as the question of the movement of the sun, both axially and through s.p.a.ce, will be considered in a subsequent article.
[Ill.u.s.tration: Fig: 11.]
Then the question arises, How far does the sun"s electric field extend?
That is rather a difficult question to answer, but the correct answer would be, "As far as the sun"s light extends, so far does the sun"s electric field extend." From the electro-magnetic theory of light we know that wherever there are light waves, there are electro-magnetic waves, though at the present moment we are only dealing with the electric aspect of those waves.
We know that the aetherial light waves reach at least as far as Neptune, a distance of 2,750,000,000 miles, therefore we know that the sun"s electric field must also extend to that distance. How much further in s.p.a.ce it extends we cannot tell, because the data on which to form a basis is inadequate.
[Ill.u.s.tration: Fig: 12.]
Thus we learn that the sun"s electric field extends east and west for that enormous distance, but we cannot say that it extends the same distance north and south. Now why is that? The first reason I should give is the well-known experiment of a revolving body, by which we learn that when a body is revolving, as the sun for example, the atmosphere around it would seek to extend itself east and west, owing to the Centrifugal Force so called. But a better reason than that will be found from an a.n.a.logy of a magnetized body. Faraday has shown in his drawings ill.u.s.trating lines of force, that if a spherical body is magnetized, the magnetic lines of force extend in circles east and west, but go out into s.p.a.ce in almost straight lines north, and south as the preceding figure shows.
Therefore, accepting Faraday"s experiment as the basis for our conception of the magnetic lines of force in the sun"s electric field, we come to the conclusion that the electric field around the sun extends east and west, while the lines of force, north and south, are more or less radial into s.p.a.ce as depicted in the figure.
Throughout the whole of the field, the electric potential, at different distances from the sun, would differ in accordance with all experiment and observation. The greatest electric potential would therefore be nearest the sun"s surface, and would be greatest in the equatorial regions of the sun, in accordance with a well-known rule which determines electric density and electric potential on conductors.
As we proceed from the sun"s surface east and west into s.p.a.ce, we should pa.s.s equipotential surfaces of different potentials. Thus the pressure on every point of equipotential surfaces would be regulated by the electric density of the Aether, which would coincide with the actual aetherial density at that point; and as the aetherial density is the measure of its elasticity or pressure, so the electric potential would correspond with the elasticity or pressure at the same point.
Thus it is possible to map out the electric field east and west by ever-increasing and widening circles which would be at lower potential the further they receded from the sun. So that by carrying out the electro-magnetic theory of light to its logical conclusion, we are able to bring the whole of the solar system into line with electric phenomena; and, as we proceed, we shall see that all other facts relating to electricity, and magnetism also, are equally as applicable thereto, otherwise this theory of light must fall to the ground.
That this conception of the universal Aether in its application to solar s.p.a.ce is not extravagant may be proved from the writings of Prof.
Tyndall and Clerk Maxwell. Tyndall, writing on the subject of Faraday"s Lines of Force, says:[26] "The aspect of these curves so fascinated Faraday that the greater part of his intellectual life was devoted to pondering over them. He invested the s.p.a.ce through which they run with a kind of materiality, and the probability is that the progress of science, by connecting the phenomena of magnetism with the luminiferous Aether, will prove these "Lines of Force," as Faraday loved to call them, to represent a condition of this mysterious substratum of all radiant action."
While Clerk Maxwell,[27] writing on "Action at a Distance," says: "These Lines of Force _must not be regarded as mere mathematical abstractions_.
They are the _directions in which the medium is exerting tension like that of a rope_, or rather like that of our own muscles." I therefore premise, that both these statements will find a literal fulfilment in the conception of the Aether advanced and perfected in this work.
[Footnote 25: _Phil. Mag._, 1861.]
[Footnote 26: Tyndall on _Light_.]
[Footnote 27: _Collected Papers_, by Niven.]
ART. 81. _Aether and Induction._--We have seen in the preceding Arts.
that the sun is an electrified body, possessing an electric field, which field possesses different intensities at different distances from its surfaces.
If such be the case, the question at once confronts us, as to what is the effect of such an electrified body with its electric field upon all the planets which revolve around it; for, if its electric field extends as far as Neptune, then all the planets and meteors, that revolve around the sun, must revolve in the sun"s electric field.
Such a question can best be answered from the consideration of experiments and theories advanced first by Faraday, who gave to the world his theory of Induction, which we shall now consider.
Let _A_ be an electrified body (Fig. 13), and _C_ be a body not electrified, but situated within the electric field of _A_. Then it can be experimentally proved, that _C_ will also become an electrified body by induction. As is well known, there are two kinds of electricity, Positive and Negative. We will suppose _A_ to be charged with positive electricity. Then it can be proved that _C_ will also be charged with negative electricity on the half nearest to _A_, while the other half will be charged with positive electricity.
[Ill.u.s.tration: Fig: 13.]
Now how has this result been brought about? According to Faraday"s theory the particles of air, the dielectric, between _A_ and _C_ play a most important part in the process. As a matter of fact, each atom or particle of air is polarized, as the process of separating the two kinds of electricity is termed, so that every atom has one half of it covered with positive electricity, and the other half with negative electricity.
For example, let _A_ and _C_ be the same bra.s.s b.a.l.l.s with the particles of air between them, _A_ being the positively charged ball and _C_ the unelectrified ball, the shaded parts representing positive electricity and the unshaded parts negative electricity.
Then _A_ will act inductively on the unelectrified ball _C_ through the medium of the particles of air _d_, _e_, _f_, _g_, _h_. The electrified ball _A_ will act first on the layer of particles next to it, attracting their negative electricity and repelling the positive according to the well-known law that "Unlike electricities attract, like electricities repel each other."
The positive electricity in the first layer then acts in the particles of the next layer in the same way, and thus the inductive action is transmitted through the particles, from layer to layer, until we come to the last layer of particles next to the ball _C_.
As the half of each atom or particle nearest to _C_ is positively electrified, then the half of the ball _C_ nearest to the layer becomes negatively electrified, while the half further away is positively electrified. Thus we say that _C_ has become electrified by induction through the polarization of the particles of air which lie between the two bodies. Faraday on this point says: "Thus induction appears to be essentially an action of contiguous particles, through the intermediations of which the Electric Force, originating at a certain place, is propagated or sustained at a distance, appearing there as a Force of the same kind exactly equal in amount, but opposite in its direction and tendencies."[28]
While again he states:[29] "Induction appears to consist in a certain polarized state of particles into which they are thrown by the electrified body sustaining the action, the particles a.s.suming positive and negative parts which are symmetrically the lines of Inductive Force." Thus in the case of any electrified body, acting on an unelectrified body at a distance, it has to be definitely understood that _the action at a distance_ is alone communicated and propagated by the dielectric or medium which exists between the two bodies. Though in the case of Gravitation it has been mathematically a.s.sumed, that action at a distance is possible, yet experimentally and physically such an a.s.sumption is philosophically incorrect, as all experience and experiment go to prove that there is no such thing as action at a distance manifested, except such action is propagated through the intervening medium, as stated and proved by Faraday.
In order to bring Gravitation, therefore, into line with our experience, it will have to be demonstrated that it, too, is the result of the action of the intervening medium, that is, the Aether, which is a result we are being led up to.
We have already seen that the sun is an electrified body, possessing an electric field, and as all electrified bodies can act on other bodies in their field inductively, then a similar result should happen in the solar system, that happens in any electrical experiment on induction, with the result that all the planets should become electrified bodies by induction, such action taking place, as Faraday points out, through the medium which divides the sun and the planets, that is, the Aether.
Of course with a frictionless and non-atomic Aether such a result would be an impossibility, but with our conception of an atomic and gravitative Aether the result is now attainable. We have therefore to think of the sun, the centre of the solar system, being an electrified body, and for ill.u.s.tration we will suppose it to be a positively charged body.
All around the sun is the atomic Aether, which is polarized in the same way that the particles of air were polarized; that is, the two kinds of electricities in the aetherial atom are separated, the negative being on that side nearest to the sun, and the positive on the side further away.
In this way the whole aetherial medium would be polarized, and any body in the field would be electrified by induction, with the result that the side nearest the sun would be negatively charged, and the opposite side positively charged.
Thus let _S_ (Figs. 10 and 11) be the sun, and the circles represent equipotential surfaces, then one half of every surface would be negatively electrified and the other half positively electrified, that is, a.s.suming the sun to be a positively electrified body.