Chapter VIII: Aether and Electricity (1)

ART. 79. _Electricity, a Mode of Motion._--The question as to What is Electricity? is one of the greatest problems of modern times. In view of the electro-magnetic theory of light, however, science is able to give a better definition as to what electricity is, than it was able to do previous to the introduction of the theory by Maxwell, and its practical establishment by Hertz.

If that theory teaches us anything at all with regard to the nature of electricity, it teaches us that electricity is due to certain motions of the universal Aether, that not only fills all so-called Space, but surrounds all particles and atoms of all Matter.

The question has been asked by various scientists, "Is Aether Electricity, or, in other words, are Aether and Electricity one and the same?" Let us look at the question from the standpoint of the analogy from the phenomena of light and heat. As we have already seen (Art. 61), heat is due to a particular kind of motion of the universal Aether, generally known as vibratory motion, which motion is communicated to the Aether by a luminous or heated body.

So that we learn that heat at any rate has an aetherial basis, as it is a particular kind of aetherial motion. From Art. 70 we learn also that light is due to an undulatory or wave motion in the Aether; the waves, however, in this case being shorter, and of more rapid vibration than those waves which give rise to heat.

Thus light and heat both have an aetherial basis, being due to vibrations of that medium. From these analogies, therefore, we come to the conclusion that electricity and magnetism have an aetherial basis, and are also due to certain kinds of motion in the Aether.

That motion may be rotatory motion or vibratory motion, as the case may be, but whatever definition we give of electricity, we cannot as yet say definitely that Aether is electricity.

We may assume, and indeed prove, that Aether has an electrical and magnetic basis, in the same way that it has a thermal or heat basis, or a luminiferous or light basis; but while we admit such a hypothesis, we cannot admit as yet that Aether and electricity are one and the same thing. It is not within the province of this work, however, to prove what electricity is, or show the relation of Aether to all the various forms of electricity with which we are conversant, but I think I may venture to make this statement, that all forms of electricity, whether it is electro-static, that is electricity at rest, or current electricity, or electro-magnetism, are due to certain forms of motion of the universal Aether, in the same way that light and heat are also particular forms of motion of the same medium. I need hardly point out that it is an absolute impossibility for me to deal with such a subject as Electricity in all its details and various aspects in one chapter; so that I shall have to assume that the reader is familiar with some of the elementary truths of the subject.

At the same time, I will endeavour to make clear most of the technical terms used as we proceed. From the Electro-Magnetic theory of light, therefore, we learn that Aether has an electrical or electro-magnetic basis, so that, wherever we get Aether, there we have the bases and conditions which will produce all the phenomena with which we are conversant in the sphere of electricity. Given the required motions in the Aether necessary to produce any particular form of electricity, then that form is produced as soon as the motions of the Aether are generated by any charged or electrified body. Produce a circular current in any way in the Aether, and you will have a circular current of electricity; produce radiations from a radiating body, and you will get electric radiations which speed away with the velocity of light.

This phase of the Aether is entirely in harmony with Dr. Larmor's Hypothesis of Electrons, which has already been referred to in Art. 44. Dr. Larmor in his work indicates that electricity has an atomic basis, and further states that "the atomicity of electricity is coming within the scope of direct experiment."[22]

Now, if electricity, as I have indicated, be due to certain motions in the Aether, then it can easily be seen that postulating atomicity for electricity will be the same as postulating atomicity for the Aether. Dr. Larmor[23] definitely and clearly states, "that each electron has an effective mass of aetherial origin, which forms part, and may be the whole, of the mass of matter to which it is attached;" and again points out (p. 64) that "an electron is nothing more than a point singularity or pole in the electro-dynamic and optical Aether." Thus we see that Dr. Larmor's hypothesis as to the atomicity of electricity is a further proof of the atomicity of Aether, and is also in harmony with the electro-magnetic theory of light.

Now in dealing with electricity as a mode of motion, it will be necessary to show that electricity is also a form of energy in the same way that heat and light are forms of energy.

If it can be demonstrated that electricity is a form of energy, then it can easily be demonstrated that work can be done by it, and that that work may take a mechanical form in the same way that the energy of heat and light may produce mechanical results. Clerk Maxwell has given us, in his greatest work, his conception of the two kinds of energy due to electricity and magnetism. On the subject he writes: "In the theory of Electricity and Magnetism accepted in this treatise, two forms of energy are recognized, the Electro-Static and Electro-Kinetic (paragraphs 630 and 636), and these are supposed to have their seat not merely in electrified or magnetized bodies, but in every part of surrounding space, wherever electric or magnetic force is observed to act. Hence our theory agrees with the undulatory theory of light in assuming the existence of a medium which is capable of becoming susceptible to two forms of energy."[24] The question has arisen many times as to what is meant by the terms Electro-Static and Electro-Kinetic energy used by Maxwell, and various hypotheses have been advanced to explain the same.

Electro-static energy is said to be that phase of electricity in which we deal with stresses set up in the Aether by an electrified body at rest, whether that body be small or large. It further deals with the process of induction, that is, the action of an electrified body upon another body, such action taking place through the medium between the two bodies. Electro-kinetic energy is the energy due to electricity in motion. On this point Maxwell says: "A conducting circuit in which the current has been set up has the power of doing work in virtue of the current, for it is really and truly energy. It appears, therefore, that a system containing an electric current is a seat of energy of some kind; and, since we can form no conception of electric current except as a kinetic phenomenon, its energy must be kinetic energy, that is to say, the energy which a moving body has in virtue of its motion." (Arts. 551 and 552.)

It is not our purpose to deal with the electro-kinetic form of energy referred to by Maxwell in this chapter. We shall deal with that form of energy due to electricity in the succeeding chapter. We will consider first the effect of the electro-static energy in relation to electrified bodies, but I wish it to be distinctly understood, that in all the different kinds of electric phenomena manifested, the Aether plays the chief part, and without it, none of the phenomena observed could be produced; because, what Aether is to light and heat, so it is to electricity, being that medium which by its motions propagates and gives rise to all electrical phenomena.

This being so, we have now to apply some of the facts taught us by electricity, and especially by the electro-magnetic theory of light, to our solar system, with the hope that we shall find further evidence of a Centrifugal Force which is physical in character, and whose action can be traced throughout the whole realm of space. Let us, in starting to apply some of the truths already learned, recall some of the facts concerning light, its production and its propagation. We recall the fact that light is produced by the action of the sun upon the Aether, giving rise to waves which speed away from the generating source with a velocity of 186,000 miles per second. We further remember that Hertz has definitely proved that these light waves are identical with electro-magnetic waves, as they ought to be if the Aether possesses an electrical basis, as Dr. Larmor and Professor Lodge suggest.

In order that there may be no mistake on this point, let me quote from one of Hertz' papers, where, in his conclusion, he says: "The experiments described appear to me, at any rate, eminently adapted to remove any doubt of the identity of light, radiant heat, and electro-magnetic wave motion." Now, what I want to point out regarding this fact is this. If the sun gives rise to the aetherial light waves, and these light waves are identical with electro-magnetic waves as proved by Hertz, then the sun must either be an electrified body or else a magnet.

It must be one or the other, because, if it were not, we should then have an anomaly in Nature of a body emitting electro-magnetic waves which is itself neither electrified nor a magnet. Therefore, according to our second Rule of Philosophy, such a body would be incapable of giving rise to these waves, as such a result would be contrary to universal experience and experiment.

We know that the earth is a magnet, but up to the present it has never been proved that the sun is a magnet, although, as I shall show later on, Lord Kelvin and others have suggested such a possibility. If we assume that the sun is a magnet, our grounds for assumption would not be so strong at this point, and our reasons so philosophical, as they are if we assume that the sun is an electrified body.

We have philosophical reasoning to prove that the sun is an electrified body in the fact that it emits or gives rise to electro-magnetic waves in the Aether, and no other hypothesis can be made other than that the sun is an electrified body, in order to prove the connection between the two.

Thus we affirm that the sun is an electrified body, which like any other electrified body is capable of generating electric waves, and speeding them through the Aether with similar velocity to that of light. Not only so, but, like any other electrified body, it must have its electric field and possess the ability to electrify any other body by induction, that may happen to be in its electric field, as we shall see later on.

Further, being an electrified body, the electric density will be greatest near the sun's surface, and this fact fully accords with our statement in Art. 45, that Aether is gravitative. As pointed out in that Art., if Aether be gravitative, it must be densest nearest to the attracting body; and, as Aether has an electric basis, then with the denser Aether there must be an increased electric density, which can only happen provided the sun is an electrified body.

Sir G. Stokes was also of this opinion, for in his Burnet Lectures on Light he writes (p. 212): "There is nothing, therefore, unreasonable in supposing that the sun may be a permanently charged body."

So that all the reasoning that has led to this result seems to harmonize and confirm each several hypothesis which has been advanced. There can be little doubt, therefore, that the sun is an electrified body, and it is for us now to carry out this fact to its logical and philosophical conclusion, by applying all the truths which circle round it to the solar system, when we shall find greater confirmation of the statement just advanced than any we have yet adduced.

According to Professor Young of America, the sun is not only an electrified body, but is also the abode of living and sentient beings. This astronomer has suggested that the sun is the centre of electric force, and that converging streams of Electricity are ever flowing to it as a centre; but on meeting with the atmosphere they give rise to brilliant discharges, which thus gives the appearance of a solid incandescent body.

Now, whether this hypothesis is correct or not, it is absolutely certain that the sun is an electrified body, as it gives rise to electro-magnetic waves in the Aether, as philosophically proved by direct experiments.

[Footnote 22: _Aether and Matter_, p. 8.]

[Footnote 23: _Ibid._, p. 64.]

[Footnote 24: _Magnetism and Electricity_, by C. Maxwell, Art. 782.]

ART. 80. _Aether and Electric Fields._--Before proceeding to apply some of the facts of Electricity to the solar system, let us find out what is meant by an Electric Field. An electric field is to an electrified body, what a thermal or heat field is to a heated body, or a luminous or lighted field is to a luminous body. If a lamp, for example, be lighted, its light waves spread out on every side, and extend for a considerable distance unless impeded by such obstacles as the wall of a room.

The extent to which the light waves reach and flow might well be called the lighted or luminous field, and in that field the effect of the aetherial light waves would be manifested and seen.

Now, in a similar manner, when any body is electrified, the electric waves spread out on every side of the electrified body, and the extent to which the waves spread out form what is known as an electric field.

So that an electric field may be defined as any region or space in which electric energy is manifested by means of the aetherial electric waves, and across which induction may take place.

Thus, for example, let _E_ be an electrified body (Fig. 9), then it will generate electric waves which will speed from the body with a velocity equal to that of light. If the body be a sphere, then the waves will be spherical in shape, and will proceed from the generating source in the shape of concentric spheres as indicated in the figure. Before proceeding any further, it is necessary that we should look at the electric field from the physical aspect, with a view to discover something of what takes place therein. As has already been indicated, all electric phenomena are due to motions of the universal Aether.

It was left for Faraday to give us a true conception of an electric field, and for Maxwell to perfect that conception and give us a physical aspect of the same. Faraday conceived that stretching out from a magnet or electrified body through space, that is, through the Aether, were what he called "Lines of Force," and that these lines of force indicated not only the direction of the magnetic and electric forces, but also their intensity or power.

Where the lines of force were closest together, there the electric or magnetic energy was the greatest and most intense; and where they were the farthest apart, there the field was weakest in energy. An illustration of the magnetic lines of force may be obtained by placing a piece of paper over a magnet, and then strewing iron filings over the same, when it will be seen that the iron filings will arrange themselves in certain curved lines, which Faraday called Magnetic Lines of Force. In this way Faraday mapped out the lines of force, relative not only to single magnets, but also to magnets with poles placed in various positions relatively to poles of other magnets.

Now as there are lines of force which reveal the intensity and direction of the magnetic energy, so there are lines of force radiating out from electrified bodies which reveal the intensity and power of the electric field. The electric lines of force are radial, and are shown in the figure (Fig. 9) by the straight lines _D_ _F_, _D_ _H_, _D_ _K_.

If an electrified pith ball, for example, be hung up in a room, then the lines of force, which extend from the ball, indicate the stress in the Aether surrounding the pith ball, so that if a hair be placed across these lines of force, any movement of the pith ball will be indicated by the motion of the hair.

It was Clerk Maxwell, however, who gave to the world a true physical conception of Faraday's Lines of Force, in his paper on "Physical Lines of Force."[25]

In the opening words of that paper he writes as follows: "We cannot help thinking that in every place where we find these lines of force, some physical state or action must exist in sufficient energy to produce the actual phenomena." Maxwell then went on to show what these physical actions were, which took place in the dielectric--that is, the medium surrounding the electrified body which we now know to be the Aether.

This electric field, he pointed out, was "in a state of stress, which consisted of pressures or tensions different in different directions at the same part of the medium. The relation of these forces were threefold, and consisted in the most general type of stress of three pressures or tensions in directions at right angles to each other."

Thus, in Maxwell's opinion, the existence of a medium, which by its physical character was able to exert energy on material bodies, was one of the fundamental hypotheses of his theory as to the physical character of Faraday's Lines of Force.

This physical medium was to be capable of certain motions, and both electric and magnetic forces were produced by its motions and its stresses. Maxwell's conception, however, of the physical lines of force was more or less hypothetical, and up to the present, as far as I can learn, has not received that authority from science that such a hypothesis requires to make it an accepted theory in science.

But what I venture to point out is, that with the view of the aetherial medium that is submitted in this work, Maxwell's hypothesis remains a hypothesis no longer, and that the hypothetical character of his theory ceases to exist. For, by our conception of an atomic and gravitative Aether, we are able to see that his physical lines of force are indeed physical, and that his brilliant hypothesis now receives a true physical foundation which otherwise it would not receive from a frictionless Aether.

There is nothing, I venture to predict, in Maxwell's hypothesis which cannot be accounted for on a truly physical basis, by the conception of the Aether as given in this work. So that when Faraday saw in his mind's eye lines of force traversing space, he saw by his imagination that which was actually the real state of affairs, and when Maxwell enlarged the conception by giving to those lines of force a definite atomic and cellular structure, he, too, but anticipated the real nature and character of the Aether as given in Chapter IV., which theory is the direct outcome of Newton's philosophical rules, and the result of discarding everything that is not in accordance with experience and observation. Thus the lines of force which exist and surround a magnetic or electrified body are as real as ocean currents, or the waves of the sea, in that they are the manifestations of the motions of the universal Aether, which is as truly matter as air or water.

Let us look at the analogy 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 quantity of electricity spread over a certain area or surface. If we double the quantity 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 quantity 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.

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 space, will be considered in a subsequent article.

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 space it extends we cannot tell, because the data on which to form a basis is inadequate.

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 analogy of a magnetized body. Faraday has shown in his drawings illustrating 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 space 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 space 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 space, we should pass 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 space 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 space 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.

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 brass balls 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 assuming 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 assumed, that action at a distance is possible, yet experimentally and physically such an assumption 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 illustration 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, assuming the sun to be a positively electrified body.

If _M_ represents Mercury, _V_ represents Venus, and _E_ represents the Earth (Fig. 10), then it can readily be seen that all these would be negatively electrified on the side facing the sun; and, as they rotate on their axes, each part of the planet would be positively and negatively electrified once each day.

We are assuming that the medium is at rest, but according to our conception in Art. 44, all the aetherial atoms are in rotation on their axes, in the same way that the earth rotates on its axis, so that each of these aetherial atoms would present different parts of its surface to the sun as it rotates on its axis; but, as that does not affect the principle of induction, such a fact need not now be fully considered.

Let us now ask, What is the result of all the planets becoming electrified bodies in the same way that the sun is an electrified body? Arguing from experience, we come to the conclusion that each planet must also possess its electric field, which also must have its lines of force, its different potentials at different distances, and its equipotential surfaces. So that Mercury, Venus, the Earth, Mars, Jupiter, Saturn, Uranus, and Neptune all have their electric fields, with their own lines of force, and with their equipotential surfaces.

If we carry the analogy further still, then it can also be proved that the Earth, and those planets which have moons or satellites, also act inductively on their satellites, with the result that they too become electrified bodies, with their own smaller electric fields and lines of force. This may seem at first sight a little confusing, but the confusion will gradually disappear if we will look at it carefully for a moment or two. Let us endeavour to picture the solar system from this new standpoint, and map out the equipotential surfaces, which this idea suggests. Let _S_ represent the sun (Fig. 14), the initials of all the planets and satellites representing the various planets; then we get the following plan of the solar system with the various equipotential surfaces shown by the circular lines.

We are now supposed to be looking down on all the solar system from above it, so to speak, so that we should be looking at what we call the North Poles of the sun and planets.

Thus we see that the equipotential surfaces around the sun are huge circles which stretch out as far as Neptune or even beyond, but within those circles we find each of the planets revolving round the sun, each with its own equipotential spheres, which are circles also, while around the various planets are the satellites, from the moon of our Earth, to the two satellites of Mars, five of Jupiter, eight of Saturn, each with its own lines of force and electric fields.

Of course we must not forget that all these revolve round the sun, and the question may suggest itself to the reader's mind, if such a result is possible. I shall prove later on, that according to Maxwell such an event is possible, but at present we will consider them stationary.

Now let us see how such a conception compares with our hypothesis of a gravitative Aether. If Aether be gravitative, then the sun must have an attraction for the Aether, and its aetherial field would stretch out into space as far as Neptune at least.

So that it can readily be seen that the aetherial field of the sun's attractive power coincides with the electric field which the sun possesses as an electrified body. Again, if Aether be gravitative, then all the planets must also have an aetherial field, which will be co-extensive with their electric field also. The same principle applies to each of the satellites, with the result that they too will possess an aetherial field which will be equal in extent and limit to their electric field.

As the satellites revolve around their primary planet taking their electric fields with them, so the planets with their associated satellites revolve around the sun taking their electric and aetherial fields with them. Thus we get a glimpse, though at this point very shadowy and indistinct, of those motions of the universal Aether, which help to constitute the harmony, beauty, and order of the universe. We have seen, therefore, that as the sun is an electrified body, so all the planets and satellites are electrified bodies also, each possessing its own field, with all that such a field implies.

We shall find that such a conception is borne out by experience and observation, when we come to deal with the Earth as a magnet; because we shall afterwards learn that the Earth is an electro-magnet, possessing its magnetic field, which is co-existent and equipollent with its electric field.

[Footnote 28: _Exp. Res._, 1297, 1298.]

[Footnote 29: Par. 1298.]

ART. 82. _Energy of the Field._--We have seen in Art. 79 that every electrified body has an electric field. We have further learned, in carrying the electro-magnetic theory of light to its logical conclusion, that all the planets and satellites together with the sun must be electrified bodies, each possessing its electric field.

We have now to determine the effect of such a truth from its dynamical aspect upon the bodies within the field, that is to say, we have to consider the energy of such electric fields, and endeavour to find out the effect of such energy upon other bodies within that field. Maxwell,[30] in his introduction to a paper on "The Dynamical Theory of the Electro-magnet Field," writes on the matter thus: "It appears therefore that certain phenomena in electricity and magnetism lead to the same conclusion as those of optics, namely, that there is an aetherial medium pervading all bodies and modified only in degree by their presence; that the parts of this medium are capable of being set in motion by electric currents and magnets; that this motion is communicated from one part of the medium to another by forces arising from the connection of these parts; that under the action of these forces, there is a certain yielding depending upon the elasticity of these connections; and that therefore energy in two different forms may exist in the medium, the one form being the actual energy of motion of its parts, and the other being the potential energy stored up in the connections in virtue of their elasticity."

The two forms of energy he gives us in his work on _Magnetism and Electricity_, where, in the quotation already given in Art. 79, he states them to be electro-static and electro-kinetic energy, while in paragraph 792 of the same work he adds: "The intrinsic energy of the medium is half electro-static and half electro-kinetic, that is, half is due to electricity and half is due to magnetism."

We are, however, only dealing at this point with the electro-static energy in the electric field, as we shall deal with the electro-kinetic energy in the following chapter.

We have, therefore, to conceive of an electrified body generating electric or electro-magnetic waves, which speed away from the generating source on every side with the velocity of light. Now we have already seen that the aetherial waves which give rise to heat and light possess a repulsive power, that is, they exert a pressure on the body with which they come into contact.

If, therefore, in the electric field there is this energy manifested as proved by Maxwell, and that energy takes partly the form of a pressure as stated by Maxwell, then we have in the electro-static energy of the electric field, another indication of that centrifugal force for which we are looking, and whose existence was so satisfactorily demonstrated to Herschel by the phenomena of comets' tails.

That there is this pressure in an electric field was conclusively proved by Maxwell, and experimentally demonstrated by Professor Lebedew (Art. 77). Maxwell distinctly states on this point, "that the combined effect of the electro-static and electro-kinetic stresses is a pressure equal to 2 P. in the direction of the propagation of the waves," that is, away from the electrified or charged body.

He continues: "Thus, if in strong sunlight the energy of light which falls on one square foot is 83.4 foot-pounds per second, the mean energy in one cubic foot of sunlight is about .0,000,000,882 of a foot-pound, and the mean pressure on a square foot is .0,000,000,882 of a pound weight. A flat body exposed to sunlight would experience this pressure on its illuminated side only, and would therefore be _repelled_ from the side on which the light falls."[31]

This pressure only gives the result due to the pressure of one cubic foot of sunlight. What must be the pressure, therefore, due to the whole of the sunlight received by the flat body from the sun? The total pressure, whatever it may be, would be equal to 2 P. according to Maxwell, and half of that is due to electricity, and half due to magnetism. Now such a result is entirely in harmony with the conception of the Aether as given in this work. For, if Aether possess an electric basis as suggested by Maxwell, and it is also gravitative as suggested in Art. 45, then it must follow, as pointed out in a previous Art., that throughout the field there is a varying difference in the potential of the field; the potential being regulated by the electric density, that density being equivalent to the aetherial density. Further, as the elasticity of the medium which regulates the pressure is proportional to the density, so the pressure must decrease, as the elasticity decreases--that is, as the electric potential decreases, or the electric density is diminished. Therefore, if the sun be an electrified body, ever generating electro-magnetic waves which speed away from it on every side, then, whenever any of these waves come into contact with a planet or comet, that planet or comet would be repelled from the sun by the pressure of these electro-magnetic waves to which the sun gives rise in its electric or electro-magnetic field.

Thus we again come to the conclusion that the sun is not only the centre of a centripetal force due to Gravitation, and subject to certain laws, whose physical cause is unknown, but it is equally the centre and source of a centrifugal force, in that it is an electrified body, and gives rise to electric waves which produce a pressure on any body upon which they fall, in the sun's electric or aetherial field. It has only to be demonstrated, therefore, that this centrifugal force satisfactorily fulfils all the laws required as laid down in Art. 24, that is, that its course is along the same path as the Centripetal Force of Gravitation, that it is subject to the same law of intensity, which is inversely as the square of the distance; and further (what is the most important at this stage), that the combined effect of the pressure of two bodies is equal to the product of their masses, then we shall have discovered that which we set out to discover, viz. a complementary force to the attractive force of Gravitation.

Unlike the centripetal force, however, the centrifugal force will be purely a physical one, due to a purely physical medium, the Aether, whose properties and motions can be accounted for on a physical, and not on a hypothetical basis.

Further, as the planets are also electrified bodies (Art. 81), they too will possess an electric field, and will generate electric waves, which will also exert a centrifugal force upon all bodies upon which the waves fall. So that, like the sun, the planets are not only the centre of a centripetal force, which ever acts towards their centre; but they are also the centre of a centrifugal force, due to the aetherial electric waves to which they give rise in the Aether.

The application of the same principle may be extended to every satellite that exists in the solar system, and indeed to every particle and atom of matter that exist throughout the universe, for wherever we find the Aether, there we find this centrifugal force, which is due to the electric aetherial waves generated by the atom or particle of matter, or by any combination of atoms, as a meteor, satellite, planet, sun or star.

[Footnote 30: _Collected Papers_, by Niven.]

[Footnote 31: _Magnetism and Electricity_, Arts. 791 and 793.]

ART. 83. _Electric Radiation._--We learn, therefore, that the sun, together with every planet and satellite in the solar system, is the centre of a centrifugal force, which is due to the radiation of electric waves by an electrified body. We have now to prove that this force fulfils all the laws required, in order for it to become the complementary law to the Centripetal Force of Gravitation. We will first show that this centrifugal force which proceeds from the electrified body is radiated out into space in straight lines with the velocity of light and radiant heat.

As we have already seen, it was due to the genius of Hertz to show the identity between electric radiation and radiant light and heat. In his paper on Electric Radiation he says:[32] "I have succeeded in producing distinct rays of electric force, and in carrying out with them the elementary experiments which are commonly performed with light and radiant heat." We have seen in Arts. 65 and 76 that radiant heat and light are propagated in straight lines, so that, according to Maxwell's electro-magnetic theory, a ray of electric radiation should also be propagated in straight lines.

This Hertz proved, and gave his results in his paper "On the Action of a Rectilinear Oscillation upon a Neighbouring Circuit," in which he fully demonstrated that when electric action takes place between two charged bodies, the electric force is radiated out into space in straight lines in the same way that light and radiant heat are radiated. In his paper on "The Finite Velocity of Electro-magnetic Actions," he showed that the velocity of the electro-magnetic waves was the same as that of light. In the summary of this paper (paragraph 3) he states: "There are many reasons for believing that the transverse waves of light are electro-magnetic waves; a firm foundation for this hypothesis is furnished by showing the actual existence in free space of electro-magnetic transverse waves which are propagated with a velocity akin to light."

Again, in his paper on "Electric Radiation," he not only showed how the radiation was propagated in straight lines, like light, but also proved that while it was reflected by metals, the electric beam was able to pass through doors and stone walls, and adds, "that it was with astonishment that one saw the electric beam appear inside a closed room after its passage through the door."

Thus Hertz has shown that both electric and magnetic effects are propagated through the Aether with finite velocity, and that that velocity is exactly the same as the velocity of light. He further proved that this propagation takes place in straight lines, in the same way that radiant heat and light are propagated. This being so, it is necessary for us to apply these truths to the solar system, with a view to find out what such a result teaches us.

We have seen in a preceding article, that the sun is an electrified body; therefore it, too, must generate these electro-magnetic waves, and radiate them into space on every side with the velocity of light. Let us try to picture the scene. Let _S_ represent the sun, and the circle round it represent the equipotential spheres which exist round the sun. (See Figs. 10 and 11.) As the intensity of the electric force is greater nearer the sun than further away, these equipotential surfaces will be closer nearer the sun than further away.