Aether and Gravitation Part 4

The theory of the Aether, therefore, which will be perfected in this work, must not only satisfactorily account for the Attraction of Gravitation on a strictly philosophical basis, but the laws, governing the pressures or tensions of that physical medium, must harmonize with each of the parts of the complex Law of Gravitation into which it has been resolved.

ART. 19. _Universality of the Attractive Force._--The principle upon which Universal Attraction rests is found in the words: "Every particle of matter in the universe attracts every other particle." It must, however, be admitted that this statement has never actually been proved.

The smallest body that Newton used to prove his Law of Attraction was our satellite the moon.

Cavendish, however, in 1798, by a series of experiments, conclusively demonstrated that the force of Gravitation existed in small bodies. He took two small leaden b.a.l.l.s of a certain weight, and fixed them at the ends of a rod about six feet long, the rod being suspended by a piece of wire in the air. Large leaden b.a.l.l.s were then brought near the small ones, and great care was taken to see if there were any twist in the wire by which they were suspended. It was found that the wire had become twisted on the approach of the large leaden b.a.l.l.s, and thus he was able to prove that every particle of the attracted and attracting body are mutually concerned in the Attraction of Gravitation. There is abundant evidence of the application of this force in relation to our earth, as we shall see later on.

The universality of the Attraction of Gravitation is a fact that has been proved in a thousand ways, and a thousand times. All stars and suns, and all planets, satellites and comets and nebulae are subject to this universal law. Astronomy teaches us that its power extends across the vast abysses of s.p.a.ce, and that stars situated at distances that cannot possibly be measured, are subject to this world-wide law. Some of the greatest discoveries in astronomical science were due to the operations of this wonderful law, the gravitating influences of certain planets indicating their existence, although their discovery had not yet been made.

The discovery of Neptune through the mathematical calculations of Le Verrier and Mr. Adams in 1846 was the crowning proof of the Law of Gravitation. Mr. Adams in England had noticed that the planet Ura.n.u.s was being pulled out of the course by some unknown power, and so set to work to calculate the position of the body which thus influenced the motion of Ura.n.u.s in its...o...b..t. He located the position of the supposed influencing body strictly by mathematical calculations, and then took his results to the Astronomer Royal. Delay, however, occurred in the search for the supposed new planet, and nothing was done further in the matter for many months. Meanwhile Le Verrier in France, unknown to Mr.

Adams, had been making similar calculations with reference to the perturbations of Ura.n.u.s, and had arrived at similar results.

These results were sent to the Berlin astronomers, and the heavens were searched for the supposed new planet. After a time, the planet was discovered in that part of the heavens indicated by Le Verrier, and for a time his name stood out as the sole discoverer. Gradually, however, the claims of Adams were admitted and recognized, and to-day his claims to partic.i.p.ate in the honour of the wonderful achievement are generally admitted. Thus the discovery of Neptune gave to the Law of Gravitation a stability and proof that perhaps it had never received before.

Further evidence of the existence of the universality of the attractive force, is to be found in a certain system of stars known as binary stars, which revolve around each other, while they gravitate around a common centre. Recent researches in astronomy only seek more and more to confirm the universality and effectiveness of this grand law, that seems to hold the entire universe in its sway.

Any medium, therefore, which is postulated as the physical cause of Gravitation, must itself be as universal as Gravitation, in order for it to be able to fulfil this condition of universality. We shall find, as we proceed, that the only possible medium which can fulfil this condition, is the universal Aether, whose qualities and properties are already partly known and partly understood.

ART. 20. _Direction of the Forces._--The attraction of Gravitation is always directed along the straight line which joins the centres of ma.s.ses of the attracting and attracted bodies. Thus, if the earth and moon are taken as examples, an imaginary straight line drawn from the centre of the earth's ma.s.s to the centre of the ma.s.s of the moon would be the direction in which the gravitative force would be exerted. Now a line which joins the central body to its satellite we shall see when we come to deal with Kepler's Laws is known as the Radius Vector. Thus the path of the attraction between the two bodies is along the Radius Vector. It is a singular coincidence that the path of a ray of light from the sun also coincides with the Radius Vector, as it is one of the laws of light that the path of a ray always follows a straight line.

It must not, however, be a.s.sumed, that while the attractive power is being exerted along any one straight line joining the centres of two bodies, therefore the attractive power is not operative in relation to any other part of the s.p.a.ce, around the body. If our earth, for example, had four moons instead of one, and they were each in different positions in relation to the earth, then the law as to the direction of the forces would still hold good. We have examples of this in the case of Jupiter with his five moons, and Saturn with his eight moons. So that the attractive force of Gravitation is again like light, it operates on all sides equally at one and the same time. A lamp in the middle of a room sends its light waves on every side at one and the same time, so that while each ray has for its path a straight line, yet those rays are emitted equally on every side. In like manner, though the direction of the forces between two attracting bodies is that of a straight line, yet the law of universal attraction is equally exerted on every side of the planet at one and the same time.

In the theory of the Aether, therefore, to be developed in this work, it will have to be demonstrated that the direction of the forces, which are originated and transmitted by that physical medium, must philosophically fulfil the conditions which govern the direction of the forces, as observed in gravitational phenomena.

ART. 21. _Proportion of the Forces._--Newton proved that the attraction is proportional to the product of the ma.s.ses of the bodies concerned.

Hence it is that the sun, which is the centre of the solar system, is capable of attracting the most remote planets, because the ma.s.s of the sun is greater than the ma.s.s of all the planets put together. Or take another ill.u.s.tration. Suppose that the sun and the earth are at equal distances from Saturn. Now the sun's ma.s.s is about 300,000 times that of our earth. Therefore if the earth draws Saturn through a certain distance in one second, the sun would draw Saturn through a distance which is 300,000 greater than the earth in the same period.

The governing principle, therefore, which decides the proportion of the attractive forces between two bodies is ma.s.s, and not simply density or volume. The ma.s.s of a body is a property which remains the same, as long as the inertia of the body remains constant. Ma.s.s is really a measure of the inertia of a body, or that property of a body by which it continues in its state of motion or of rest.

Ma.s.s is therefore a compound quant.i.ty, being equal to volume multiplied by density, so that if the volume of any body is halved, the density is doubled. Thus, the proportion of the attractive force between any two bodies ever remains the same, so long as the ma.s.ses of the two bodies remain the same. Through all the changes of volume and density of any body, its attractive force remains constant, as long as the ma.s.s remains constant; for the simple reason, that as the volume of a body is increased, the density is proportionately decreased; or, as the volume is decreased, the density is increased.

For example, the volume of the sun as compared with the volume of the earth, is about 1,300,000 times greater, but the proportion of the attractive forces between the two bodies, is about 324,000 to 1. This difference is accounted for by the fact, that the density of the sun is about one quarter the mean density of the earth, hence their ma.s.ses are in the proportion of 324,000 to 1. Thus the proportion of the attractive forces between any two bodies is dependent upon their ma.s.ses, and not simply upon their volume or density.

ART. 22. _Law of Inverse Squares._--The Law of Inverse Squares which is applicable to Gravitation is equally true of Sound, Light, Heat and Electricity, the Law being that Gravitation acts inversely as the square of distance. That is to say, if the distance of any body from the sun, for example, be doubled, then the force of Gravitation is diminished to one quarter of the intensity which would be exerted on the body in the first position.

Thus the further a body is from its controlling centre, the weaker the Attraction of Gravitation upon it becomes. Taking therefore Mercury and the earth as examples, we find that their mean distances are respectively 35,000,000 miles and 92,000,000, which is a proportion of about 1 to 2-1/2. So that the intensity of the sun's attraction on the earth is about four-twenty-fifths of what it is on Mercury, that being the inverse square of the relative distances of the two bodies.

Now the intensity of Light and Heat received by the earth is regulated by the same law of inverse squares, so that the earth would receive about four-twenty-fifths the intensity of light and heat which Mercury receives when they are both at their mean distances.

This law of inverse squares is applicable to every body which acts as a gravitating source throughout the whole of the universe, whether that body be small or large, and whether it be in the form of meteor, satellite, planet, sun or star.

Each satellite, planet or sun exerts an attractive influence upon every body that exists, that attractive influence being regulated by the ma.s.ses of the respective bodies, and decreasing inversely as the square of the distance from the body viewed as the centre of attraction. So that, the further the attracted body is from the attracting body, the less is the intensity of the mutual attracting forces, though that intensity does not vary simply as the distance, but rather as the square of the distance, and that in its inverse ratio. Thus if we take two ma.s.ses of any kind or sort, and place them at various distances as represented by the numbers 1, 2, 3, 4, 5, 6, the intensity of the attracting forces between the same ma.s.ses at the relative distances will be represented by the numbers 1, 1/4, 1/9, 1/16, 1/25, 1/36, which are the inverse squares of the respective numbers representing their distances. As we shall see, the same law holds good in relation to heat, light and electricity, and indeed to all forms of energy which radiate out from a centre equally in all directions.

There is no need to apply Newton's Rules of Philosophy to this Attraction of Gravitation, as it has been demonstrated to exist, times without number. Moreover its laws are exactly the same as those governing the phenomena of sound, light, heat, and electricity, so that apart from being proved by actual experiments in relation to the gravity of the earth, we have a wider experience of the application of the same ruling principles of the law in other departments of science.

The Law of Universal Attraction, which is strictly the Centripetal Force of the compound Law of Gravitation, fully satisfies the three governing rules of Newton's Philosophy. Not only is it simple in its conception, but it is borne out by experience, and adequately accounts for the distinctive phenomena which it seeks to explain. By it, astronomical observations can be taken with a precision and certainty that defy error or failure. The motion of a planet in its...o...b..t can be so perfectly calculated, that its position in s.p.a.ce in relation to other planets can be foretold years in advance. The theory of the Aether, therefore, which is to be perfected in this work, must philosophically show that the pressures or tensions of that medium, which are postulated as the cause of Gravitation Attraction, must themselves fulfil the laws of inverse squares, which govern light, heat, electricity and the Attraction of Gravitation. I premise that this will be done in the theory of the Aether to be submitted to the reader in the after pages of this work.

ART. 23. _Terrestrial Gravity._--Before pa.s.sing from this phase of the subject, I should like briefly to look at the question of the Attraction of Gravitation from the standpoint of our own earth, as by so doing we shall notice some facts regarding the same, hitherto unnoticed, in the preceding articles.

Terrestrial Gravity is but a phase of Universal Gravitation. One of the most familiar facts and phenomena of everyday life is, that when a body, such as a stone or stick or bullet, is thrown or projected into the air, it always falls to the earth again. This is due to the attraction of the earth and the stone for each other. It has been proved experimentally that if a stone and a weight are let fall from a height of 16 feet, they would reach the earth in one second of time. Again, a feather, or cork, or even a piece of iron would take exactly the same time falling through the same s.p.a.ce, provided that the feather or cork could be screened from the resistance of the air.

The distance, however, through which a body falls in one second varies at different parts of the earth's surface, being least at the equator, and greatest at the North and South Poles. This is accounted for by the fact that the polar diameter is only 7899 miles, while the equatorial diameter is 7925 miles, thus the distance from the centre of the earth to either pole is about 3950 miles, or 13 miles less than the equatorial radius of the earth. Now the force of gravity decreases upwards from the earth's surface inversely as the square of the distance from the earth's centre of gravity, but decreases downwards simply as the distance from the centre decreases. Thus if a ball were taken down 2000 miles, that is half the distance to the centre, it would only weigh half-a-pound, while if it were taken to the centre of the earth, it would have no weight at all; while a pound weight at the equator would not weigh one pound at the poles, because it would be nearer the centre of the earth by 13 miles.

Thus a pound weight is not always a pound weight. It varies as we carry it to different parts of the earth's surface, depending upon its relation to the centre of the earth for its exact weight. The point which I wish to make perfectly clear, as it will be necessary for future reference, is, that there is no such thing as weight apart from the gravity of the earth; or, if we apply the principle to the solar system, there is no gravitating force in that system apart from the gravitating force of the central body, the sun, or the planets and other bodies which form the solar system.

Let us look at this matter from another standpoint, in order to prove this truth and make the same perfectly clear. If a pound weight were put in a spring-balance, then at the surface of the earth it would weigh one pound. Now, we will suppose that we have taken the weight to a height of 4000 miles above the surface of the earth, that is exactly double the distance from the centre of the earth, the radius of the earth being approximately 4000 miles. According to the law of inverse squares, the force of Gravitation decreases inversely as the square of the distance.

The distance having been doubled, the proportion of the forces at the two places, _i. e._ the earth's surface and 4000 miles above it, are as 1 to 1/4.

Thus at a distance of 4000 miles the weight which weighed one pound at the earth's surface, now only weighs a quarter of a pound. At a distance of 8000 miles, the distance would be trebled, therefore the force of Gravitation is one-ninth, and the weight would weigh one-ninth of a pound. If we could take the pound weight to the moon, the attractive force of the earth would be reduced to 1-3600, as the moon is 240,000 miles distant, that is sixty times the earth's radius. The square of 60 is 3600, and if we invert that we get 1-3600, so that the weight which weighs a pound at the earth's surface, would only weigh 1-3600 part of a pound at the distance of the moon. This again proves, that apart from the Attraction of Gravitation, there is no such thing as weight, and that the weight so called of any body, such as a planet or satellite, increases or decreases as its distance increases or decreases from its central attracting body.

ART. 24. _Centrifugal Force._--I have already shown in Art. 10 that the Centripetal Force and Universal Attraction are one and the same; as the Centripetal Force always acts towards the centre, and must therefore be in its operation and influence a gravitating or attractive power.

I have also pointed out in the same article, the necessity of another force, which is to be the complement, and the counter part of Gravitation Attraction. That complement and counter force was conceived by Newton, and called by him the Centrifugal Force. The very nature of the Centripetal Force demands and necessitates a force which in its mode of operation is exactly the opposite of the Centripetal Force. Unless there were such a force, a repellent and repulsive force, then instead of there being that harmonious working of the universe that now exists, there must inevitably be a gradual drawing together of all planets and satellites, of all stars and suns, into one vast, solitary, and ruinous body.

There are also other phenomena which demand a Centrifugal Force in the universe. It is a well-known fact, that there exist between the orbits of Jupiter and Mars, what are called planetoids, about 500 in number, which are supposed to be the remnants of a broken or shattered world. As may be expected from such an acc.u.mulation, they present the most extraordinary diversities and eccentricities in the orbits that can possibly be conceived. They are of all shapes and sizes, and besides their orbits round the sun, have orbits among themselves. They are so cl.u.s.tered together that their orbits intersect each other at numerous points, and when in conjunction are said to suffer great perturbations, being pulled great distances this way and that by each other's attractive influence. It is further stated that their orbits so intersect each other, that if they were imagined to be material rings, they would be inseparable, and the whole could be suspended by taking any one of them up at random. Here, then, is presented to us a kind or order of celestial phenomena for whose well-being and effectual working the Centripetal Force or the Attraction of Gravitation cannot possibly account. In their case another force is demanded which shall be the exact complement and counterpart of the Centripetal Force. There needs therefore a force, not an imagined one, simply conceived to fill a want, but a real Force, as real and as plainly to be understood as the Centripetal Force. A force existing in each world just like the Attraction of Gravitation, only the reverse of Gravitation, a repellent, repulsive Force, acting in the reverse mode, and way, to universal attraction. This Force must be governed by the same rules and laws that govern the Centripetal Force, if it is to work in harmony with the same.

It must be universal in its character, having a proportion of forces equal to the product of the ma.s.ses of the two bodies which are concerned, and its path must coincide with the path of gravitational attraction, that is, in the straight line which joins the centres of gravity of the two bodies. Further, and what is perhaps the most important of all, it must act as a repelling or repulsive force which shall be in the same proportion in regard to distance, as the law governing Centripetal Force, that is, inversely as the square of the distance.

Again, and briefly, there are also in existence small bodies called meteors, which are said to exist by myriads, which float in s.p.a.ce, and circle round the sun. They are of all shapes and sizes, from one ounce to a ton or even tons, thousands of them coming into contact with our earth's atmosphere every year, especially in August and November. All of these small bodies have orbits among themselves, and gravitate round one another, as they revolve round the sun. Now if the orbits of the planetoids be such an entangled ma.s.s, what must be the orbits of these meteors? What an indescribable, unimaginable ma.s.s of labyrinthian motions must exist among these myriads of little bodies! How they must intersect, cross and intermingle each other's...o...b..ts! What attraction and counter-attraction they must exert upon each other! Let me ask any man to sit down and try to imagine how the present recognized Centripetal and Centrifugal Forces can account for the effectual working of these meteors. As ill.u.s.trating the necessity of a real and physical Centrifugal Force which is to be the exact counterpart of the Centripetal Force, I would call the attention of the reader to Herschel's view of this matter. In dealing with the phenomena of comets'

tails he writes:[1] "Beyond a doubt, the widest and most interesting prospect of future discovery, which this study holds out to us, is, that distinction between gravitating and levitating matter, that positive and irrefutable demonstration in nature of a repulsive force, co-extensive with, but enormously more powerful than the attractive force we call gravity which the phenomena of their tails afford." I premise that this prophecy of Herschel's will be fully demonstrated and proved in the succeeding pages of this work. For, in the theory of the Aether that is to be afterwards perfected, it will be philosophically proved that the physical medium so conceived will satisfactorily account for a force or motion from the centre of all bodies; which motions fulfil all the conditions required by that Centrifugal Force, which is the complement and counterpart of the Attraction of Gravitation. At the present time, with the conception of a frictionless Aether, it is impossible to harmonize the existence of such a force or motion with our theory of the Aether. Yet Professor Lebedew of Moscow, and Nichols and Hull of America, have incontrovertibly demonstrated by actual experiments the existence of such a force. Therefore it follows, that if our present theory of the Aether fails to agree with experimental evidence, such a theory must be reconstructed in order that our philosophy may be made to agree with our experiments and our experience.

[Footnote 1: _Lectures on Scientific Subjects._]

ART. 25. _Kepler's Laws._--A long time before Newton had discovered the Law of Gravitation, Kepler had found out that the motions of the planets were governed by certain laws, and these came to be known as Kepler's Laws.

These laws which were given to the world by Kepler, simply represented facts or phenomena which had been discovered by observation, as Kepler was unable to account for them, or to give any mathematical basis for the same.

On the discovery, however, of Universal Gravitation, Newton saw at once that these laws were simply the outcome of the application of the Law of Gravitation to the planets, and that they could be accounted for on a mathematical basis by the Law of Gravitation, as they seemed to flow naturally from that law.

Kepler's Laws are three in number and may be thus stated--

_1st Law._ Each planet revolves round the sun in an elliptic orbit, with the sun occupying one of the Foci.

_2nd Law._ In the revolution of a planet round the sun, the Radius Vector describes equal areas in equal times.

_3rd Law._ The squares of the periodic times of planets are proportional to the cubes of their mean distances.

Now the question arises, whether it is possible to form a theory of the Aether which shall satisfactorily and philosophically account for all the phenomena a.s.sociated with Kepler's Laws in their relation to the motions of planets, satellites, or other solar bodies? On the present conception of the Aether such a result is an absolute impossibility.

With the theory of the Aether, however, to be submitted to the reader in this work, the result is possible and attainable. If, therefore, such a result is philosophically proved, as I submit will be done, then we shall have greater evidence still that the theory so propounded is a more perfect theory than the one at present recognized by scientists generally.

ART. 26. _Kepler's First Law._--Each planet revolves round the sun in an elliptic orbit, the sun occupying one of the Foci.