Fig: 25.
The Earth we know is moving with a velocity of about 64,800 miles per hour around the sun, or an average velocity of 18 miles per second, so that while the Earth is moving 64,800 miles through space to perform the half-circle,E D C, the sun is also travelling 18,000 miles towards the pointD.
What, therefore, is the effect of this onward movement of the sun towards the Earth as it tries to complete the half-circleE D C? We have seen that the centrifugal force due to the pressure of the electro-magnetic Aether waves is exactly equal to the centripetal forceexerted by the sun on any planet, and if that be so, it can be readily seen that as the sun journeys towards the pointDof the Earth's orbit, it tends to approach nearer and nearer the Earth. Thus the intensity of the aetherial pressure owing to the decreased distance will be greatly increased, and the effect of the increased pressure of the Aether upon the planet will be to push it away from the sun, so that the two forces may be equalized, and its mean distance, which is definitely fixed, be maintained as far as possible.
The result will be that, instead of the Earth describing the half-circleE D C, it actually describes the part of the ellipseE F C. Thus it can be seen that while the sun is travelling through space, it is at the same time giving rise to the electro-magnetic Aether waves, which, by their repelling power, repel the Earth from the sun in the direction that the sun is travelling, and hence the half-circle is elongated into that part of the elliptic orbit known as the perihelion, which is that part of the orbit where the distance of any planet from the sun is the least.
Fig: 26.
The repelling power of the Aether waves is not, however, sufficient to overcome altogether the centripetal force in conjunction with the Earth's motion, with the result that when the Earth arrives atF, its distance is only 91 million miles, that being the least distance between the sun and the Earth. We shall see the result of this decreased distance when we deal with Kepler's Second Law.
We will now proceed to notice the effect of the sun's orbital velocity upon that part of the Earth's orbit which includes the aphelion, or that part in which the Earth occupies a position of the greatest distance from the sun. Proceeding on the same method of reasoning, if the sun were stationary, with the Earth being circled round it by the electro-magnetic Aether currents, then the path described by the Earth would be that of a circle, being represented by the half-circleC G E(Fig. 26).
But it has to be remembered that while the Earth is being circled round the sun by the rotatory electro-magnetic Aether currents, the sun isstill travelling on towardsS Fat the rate of 18,000 miles per hour, while the Earth is travelling in almost an opposite direction towardsC G, so that by the time the Earth has got toG, which we will suppose is one quarter of its ellipse, the sun has travelled millions of miles in that time.
Thus it can readily be seen, that by the time the Earth has got to its aphelion, it is at its furthest distance from the sun, simply because the sun has been travelling onwards through space all the time, while the Earth has been receding from it; and as the motion of the Earth has been in an opposite direction, the mean distance has been exceeded, and instead of the Earth being now at its mean distance from the sun, its distance is now 94,500,000 miles. At that part of its orbit, its orbital velocity is at a minimum, because the rotating Aether currents have there a decreased flow and a decreased mass and density, and therefore possess a decreased kinetic energy or motive power.
Thus by the rotating Aether currents working in conjunction with the centrifugal and centripetal forces, can be accounted on a physical basis the first of Kepler's Laws in a manner which is strictly philosophical, as the explanation is simple in conception, does not violate experience or experiment, and satisfactorily accounts for, on a physical basis, the law which it is required to explain.
If we consider the rotating Aether currents as purely currents of electricity, then exactly the same results follow. For, as we shall see later, Professor Lodge in hisModern Views of Electricityproves that electricity possesses both inertia and momentum, and if electricity possesses these properties, then it also possesses the requisite properties to enable the currents to propel or push any planet around its central body, or a satellite round its primary planet. Therefore the same course of reasoning that applies to the rotating Aether currents, equally applies to the currents of electricity that circulate round each satellite, planet, and sun and star, and by that circulation gives rise to the electro-magnetism associated with each body, while at the same time they supply the kinetic energy which enables any dependent or associated body to be propelled round their controlling centre.
Art. 103.Second Law of Kepler.--According to Kepler's Second Law (Art. 27), we learn that the radius vector, which is the imaginary straight line joining any planet to the sun, describes, or sweeps over, equal areas in equal times. So that, while Kelper's First Law describes the path which a planet takes in revolving round the sun, the Second Law shows how the velocity of that planet varies in different parts of its orbit.
While, however, there is a difference in the velocity of any planet at various points in the orbit, there is still a proportion existingbetween its various velocities, in that equal areas are covered in equal times. We have now to apply the hypothesis of our rotatory Aether currents, in conjunction with the centripetal and centrifugal forces, in order to see whether the Second Law of Kepler can be explained on a physical basis, in the same way that Newton explained it from the mathematical standpoint.
We have again to conceive the sun as the centre of two equal but exactly opposite forces, and also possessing a rotatory motion on its axis, with the electro-magnetic Aether currents ever circulating round it. If the sun were stationary, it will be manifest at once that Kepler's Second Law would be literally and strictly fulfilled, for in that case the orbit of all the planets would be perfect circles, and the motion of planets in their orbits would be perfectly uniform, and therefore equal areas would be covered by the radius vector in equal times. Thus any quarter of the orbit would be described in exactly a 1/4 of a year, 1/12 in 1/12 of a year, 1/40 in 1/40 of a year, and so on, the time being exactly proportional to the proportion of the area covered by the radius vector.
The area covered would always be uniform, because the radius vector would always be uniform in length. But, as we have seen in the previous article, the distance of a planet from the sun, that is, the length of the radius vector, is not uniform, as the Earth is nearer to the sun at perihelion, and further away at aphelion, its distance gradually changing as it passes from each of these points to the other.
Now what is the effect of the decreased distance upon the circulating or rotatory Aether currents? We have already seen (Art. 99) that the closer these Aether currents are to the central body, the sun, the greater is their velocity and the greater their mass, so that the total impressed force which they exert over any planet is greater the nearer that planet is to the sun. This is proved by the fact that Mercury has a greater orbital velocity than Venus, Venus than the Earth, the Earth than Mars, and so on right through the whole of the planetary system. In view of these facts, let us again consider the effect of the sun not being stationary, but having an orbital velocity of its own through space. Thus let the sun be atSand the Earth be at pointDof its orbit (Fig. 25).
The circulating Aether currents are ever acting upon the Earth, carrying it round the sun with them, while at the same time the centripetal force is pulling it towards the sun with a certain intensity, but the centrifugal force is repelling the Earth with exactly the same intensity, and if the sun remained motionless the two forces would exactly balance each other, while the Earth would describe the half-circleE D C. But while the Earth is moving towards the pointDwith a velocity of 64,000 miles per hour, the sun is also moving at thevelocity of about 18,000 miles per hour towards that point.
Thus the repelling power of the radiating electro-magnetic Aether waves has to overcome, not only its exact counterpart, the centripetal force, but also the onward motion of the sun as it rushes on its course through space. This the centrifugal force is unable to do, with the result that the distance is gradually lessened, and instead of the Earth describing the arcE D, it describes the arcE F, at which point its distance is at the minimum, or about 91 millions of miles.
Or, to put the same fact in another way. When the Earth is atE, the centripetal force and the orbital velocity of the Earth and the sun are acting conjointly, with the result that they overcome the centrifugal force, and the distance is gradually decreased. This decreased distance means an increased aetherial density and an increased velocity of the aetherial currents, with the result, that as the distance is decreased, the orbital velocity of the Earth is gradually increased, so that by the time the Earth gets toF, at its perihelion, it has now acquired its greatest orbital velocity, and is carried round the sun by the electro-magnetic Aether currents at its maximum velocity.
Now let us look at the Earth being circled round the sun by the electro-magnetic Aether currents as it goes on to perform the other half of the orbit. In this case we have the orbital motion of the sun and the centrifugal force working conjointly, with the result that together they overcome the centripetal force, and the Earth is repelled and carried beyond its mean distance. LetSrepresent the sun, the Earth being at pointCof its orbit, after passing round its perihelion, and at this decreased distance it is carried along by the circulating and denser Aether with its maximum velocity (Fig. 26).
Now while the Earth is going on to describe the half-circleC G E, the sun is still pursuing its journey at the rate of about 18,000 miles per hour, only this time in a direction away from the Earth. As, however, the Earth has not yet regained its mean distance of 92,000,000 miles, the centrifugal force is still greater than the centripetal force, so that the centrifugal force is urging the planet away from the sun with greater intensity than the centripetal force is attracting it, as the two forces are only in equilibrium at the mean distance of the Earth.
Thus, as stated, the orbital motion of the sun and the centrifugal forces are now working conjointly together, with the result that the Earth is repelled gradually further and further from its central body, until it reaches its maximum distance of 94,500,000 miles. While, however, the distance is gradually being increased, it is passing into a part of the Aether possessing not only a decreased mass, but also adecreased velocity, with the result that the motive power or kinetic energy of the aetherial currents at the increased distance is gradually lessened, and as a natural result the velocity of the Earth is also decreased; so that by the time the Earth has got to its furthest distance from the sun, its orbital velocity is slowest, because of the decreased momentum of the aetherial currents.
Thus we can account for the difference of velocity of a planet in its orbit by the same electro-magnetic Aether currents working in conjunction with the sun's orbital motion, and that upon a strictly physical basis. This result is in perfect harmony with Kepler's Second Law, which states that equal areas are described by the radius vector in equal times. Newton proved that by the Law of Gravitation Attraction he could account for this second law, as well as all the others, and as we have not destroyed that law, but perfected it by giving it its exact complement and counterpart, the same mathematical reasoning that applies to the centripetal force must equally apply to the centrifugal force, and if it is true that the centripetal force works harmoniously with the second of Kepler's Laws, then it is equally true that the centrifugal force does also, as the two are inseparably and indisputably united together in the atomic Aether. We have, however, a physical basis for this centrifugal force, and we have an equal physical basis for the centripetal force, as we shall see later, and therefore, by the conjoint working of these two forces taken in conjunction with the orbital motion of the sun, we have now a physical conception for the first time of Kepler's Laws, as well as a mathematical conception, that physical conception being derived from the pressure and motions of the universal Aether.
Art. 104.Aether and Kepler's Third Law.--InArt. 28we saw that according to the Third Law of Kepler, the square of the periodic time was proportionate to the cube of the mean distance of that planet from its controlling centre. Newton proved that this Third Law was mathematically correct, and that it could be mathematically accounted for by the existence and operation of the universal Law of Gravitation. As the centrifugal force is the exact opposite of that force in intensity, proportion and mode of operation, it follows that mathematically the centrifugal force also bears the same relation to the Third Law that the centripetal force does.
We have, however, a physical basis for the centrifugal force, and it is with the physical conception of this Third Law rather than with its mathematical character that we are now dealing. Kepler by his Third Law showed that the chief regulating factor in the orbital velocity of a planet was its mean distance from the sun.
The great regulator of the velocity of any planet in its orbit issimply planetary distance, and planetary distance alone. If there were no other law which operated in the solar system than the centripetal force, or the attractive force due to gravity, then such factors as mass and density of a planet ought to play a most important part in the orbital velocity of a planet, as the centripetal force directly recognizes the influence of mass, that is, volume and density, but says nothing about mean distances. This fact unmistakably points to the existence, and demands the operation, of another force, which shall explain, and that on a physical as well as a mathematical basis, how it is that the mean distance of a planet from any centre regulates the orbital velocity of that planet.
The only real and true conception of such a force is to be found in the radiating waves and circulating motions of the aetherial medium, which waves, like water waves, increase in their radial outflow and extent with a regular decreasing intensity, and at the same time decrease in their angular velocity as they recede from the sun. With such a regular decrease of kinetic energy, there must necessarily be imparted to the planets, as their mean distance is increased, a decreased velocity of motion, with the natural result, that the further a planet is from the sun, the less will be its orbital velocity, and that in a regular and uniform proportion as the distance is increased.
Now let us view the matter for a moment in its application to the solar system, and by so doing show the simplicity of the explanation, and at the same time give added proof to the existence and operation of the circulating aetherial currents that exist in space. Let us again picture the solar fires burning in all their fierceness and intensity, every atom and particle of the sun being thrown thereby into the most intense state of activity, and by their energy of motion creating electro-magnetic Aether waves in their myriads, which speed away from the sun on every side.
Under their influence, all subordinate worlds would be carried away into space, were it not for the complementary Law of Gravitation Attraction, that is, the centripetal force. But to every planet, by the operation of some governing and determining principle, a mean distance has been given, and at that mean distance the two forces find their equilibrium; and by their conjoint and co-equal working hold each planet at that mean distance with a power that cannot be broken. Each power or force may be modified under certain conditions, as shown in the two preceding articles; but, whether the planet be repelled further away, or attracted nearer to the sun, through the onward motion of the sun, the two forces ever seek to maintain their equilibrium, and to place the planet at its mean position assigned to it in the solar system.
The nearer that mean position is to the sun, the greater is the velocity of the aetherial currents which circulate round the sun; and the greater their mass, volume for volume, on account of the increasing density of the Aether, the nearer it is to the sun. The effect of this increased velocity, and the increased mass of the circulating Aether currents, is to impart to planets nearest to the sun the greatest orbital velocity; while, the greater the distance, the less will be the orbital velocity of the planet. That this is exactly in accordance with observation and experience may be proved by considering the respective mean distances and orbital velocities of the various planets.
Mercury, with a mean distance of 35,900,000 miles, is circled round the sun at the enormous rate of about 108,000 miles per hour, accomplishing its entire journey in the short period of 88 days. Venus, whose mean distance is about 67,000,000 miles, is carried round the sun at the reduced rate of 78,000 miles per hour, completing her orbit in the increased time of 224 days. Our own Earth, at the still further increased mean distance of 92,000,000 miles, performs her journey at the reduced velocity of 64,000 miles per hour, accomplishing the journey round the sun in a period of 365 days.
Thus, the further we get from the sun, the slower becomes the movement of a planet in its orbit, and the longer it takes to complete its revolution round its controlling centre. Mars, at the increased distance of 141,000,000 miles, possesses a reduced velocity of 54,000 miles per hour, and completes its orbit in the increased duration of 686 days. So the decrease of velocity goes on, as the planets increase their mean distance from the sun, as the following figures show--
The relation of this decrease of velocity to the mean distance is exactly determined by Kepler's Third Law, in which he states that the square of the periodic time is proportionate to the cube of the mean distance. That this is true has already been proved inArt. 28.
In conclusion on this point, let me ask the reader to try to conceive any other physical explanation for this decrease of orbital velocity as the mean distance is increased, than the one given here, namely, the decrease in the velocity and mass of the radiating and circulating Aether currents, and if such attempt is made, I premise that its onlyresult will be utter failure. No other physical conception to account on a physical basis for all Kepler's Laws can be given or conceived, than that which finds its origin in the universal electro-magnetic Aether, which by its pressures, tensions and motions gives rise to all the phenomena incidental to, and associated with, planetary and stellar phenomena.
Therefore, inasmuch as all the laws of motion, and all Kepler's Laws can be accounted for by a gravitating and rotatory Aether medium, those facts alone, apart from the explanation of other phenomena associated with light and heat, would stamp the circulating Aether medium as the physical cause of all the motions and phenomena associated with the whole of the celestial mechanism.
Art. 105.Orbital Motions of Satellites and Planets.--According to Kepler's First Law, the Earth and all the other planets move round the sun in orbits which are in the shape of an ellipse. Not only, however, is the first law true of planetary motion, it is equally true of the motions of all satellites moving round their primary planets. I wish, however, to point out, and prove in an indisputable manner, that Kepler's First Law does not sufficiently explain and determine the exact orbit of any satellite as it revolves around its primary planet, or even of any planet as it revolves around the sun.
Simply because, if any satellite or planet is to perform a perfect ellipse as it revolves around its central body, that central body must only move for a time and must then come to rest, or partly return in its journey in order for a perfect ellipse to be formed, as shown in a previous figure. Now we know from observation that such a thing as rest in space by any planet, or by the sun, is absolutely unknown in the celestial mechanism.
FromArt. 92we learned that the electro-magnetic Aether currents not only circulate round the sun, but they also circulate round each planet. Thus we found there were electro-magnetic Aether currents circulating round each planet, while those planets themselves were circled round the sun by the Aether currents generated by the sun; the planetary Aether currents in their turn propel the satellites round their primary planets. It can easily be seen, therefore, that such phenomena as rest and return of a planet in its journey are physical impossibilities, for either the circulating Aether currents would have to cease circulating, or would have to return upon themselves in some inconceivable manner.
Thus there is ever going on this conjoint motion, so to speak, of the sun's aetherial currents which circle all the planets round that body, and the planetary aetherial currents which circle all the satellitesround their central body, and it is the effect of the conjoint working of these currents on the planets and satellites to which I wish to call the reader's attention.
Let us in starting represent the earth's orbit by a perfect ellipseA B C D, with the sun occupying one of the fociS(Fig. 27). We will suppose that the earth is at pointAof its orbit and is being circled round the sun with uniform velocity. As it is circled round the sun by the sun's aetherial currents, at the same time its satellite the moon is being circled round the earth by the electro-magnetic Aether currents which circulate round that planet. We will represent the orbit of the moon by part of a smaller circleD E F, and suppose the moon to be at pointDof that orbit. The mean distance of the moon from the earth is about 240,000 miles, so that the diameter of the orbit is 480,000 miles, therefore the circumference of the orbit is 480,000 × 3.1416, which gives us about 1,500,000 miles.
Fig: 27.
That distance is traversed in about 28 days, so that the moon's average velocity in its orbit, as it is circled or pushed round the earth, is about 2200 miles per hour. While, therefore, the moon is travelling 2200 miles, the earth in its journey round the sun has travelled about 64,800 miles in the same time. So that by the time the moon has travelled half its orbit, that is, fromDtoF, which would take about 14 days, the earth has also travelled in its orbit 64,800 × 24 × 14 = 21,772,800 miles, with the result, that instead of the moon arriving at pointF, which it would do if the earth were stationary, it really arrives at a point about 21,772,800 miles in front of that point.
In a similar way, while the moon goes on to describe the other half ofthe orbit, the earth still proceeds on its journey, so that at the end of 14 days it is again 21,772,800 miles further on, with the result, that the centripetal force (by which the moon is attracted to the earth) keeps it at the distance of 240,000 miles according to Kepler's Second Law as explained inArt. 103.
The moon, therefore, completes its orbit about 21,772,800 miles further on than it would do if the earth were stationary. The effect of this continual progress of the earth on the moon's orbit as it describes its orbit round the sun is seen in the diagram. As the moon revolves round the earth thirteen times in one year, it performs thirteen revolutions round that planet; but it cannot be said that these orbits are perfect ellipses, as the earth is ever being circled round its central body, the sun. Even this diagram does not accurately represent the orbital motion of the moon through space, as it assumes that the earth returns to the same point in space from whence it started. This, however, is incorrect, as we have to remember that the sun has also an orbital velocity of 18,000 miles per hour, so that while the earth has performed one revolution in its orbit, the sun has actually progressed through space to the extent of 18,000 × 24 × 365 = 157,680,000 miles.
When we come to deal with the sun's motion through space, we shall see that this distance only represents a fraction of the sun's orbit, as it can be philosophically proved, that if the sun moves at all, it, too, obeys Kepler's Laws; and therefore, according to his First Law, it also describes and possesses an orbit of its own. So that by the time the earth has made its annual revolution round the sun, the whole system has been carried 157,680,000 miles through space, and therefore the earth does not complete a perfect ellipse, but its orbital motion round the sun will be represented by a similar kind of diagram to the one which represents the orbital motions of the moon, or any other satellite round its central body.
Art. 106.Eccentricity of Orbit of Moon.--From astronomical observation we learn, that all the satellites and planets do not possess uniformity of motion, as they are carried round their controlling centres by the circulating aetherial currents, because the respective controlling centres themselves move through space. The result is, that the orbit of any satellite or planet is not always of the same size, but constantly varies, sometimes having a larger circumference than at other times, and sometimes a smaller circumference.
This change in the size of the orbit of a satellite or planet is known as the eccentricity of the orbit, which eccentricity is constantly changing, being sometimes greater and sometimes less. We will look at this truth in its relation to the moon first, and then consider thesame principle in its relation to the earth and other planets later on. For the purpose of illustration, we will consider the earth as being circled round the sun by the electro-magnetic Aether currents in a closed orbit,A B C D, which forms a perfect ellipse, the sun occupying one of the fociS(Fig. 28), the earth occupying a position in the orbit represented by pointC, with the moon being circled round the earth by that planet's aetherial currents. As we have already seen inArt. 103, according to Kepler's Second Law, at this point the earth is furthest from the sun, being now at a distance of 94-1/2 millions of miles, and therefore its orbital velocity will be slowest at that part of its orbit.
If it were absolutely at rest in space, and simply revolving on its own axis, then the result would be that the moon would be circled round the earth in an orbitM C Fwhich is perfectly circular in form; but, as the earth is being carried along slowly through space by the circulating Aether currents, this onward movement changes the circular orbit into an orbit of elliptic form.
Fig: 28.
The eccentricity of the moon's orbit when the earth is at its aphelion, or furthest from the sun, is now at a minimum, for the simple reason that the earth is proceeding slowly through space, owing to the decreased kinetic energy of the aetherial currents at the increased distance.
So that, at this point of the earth's orbit, the difference between the two axes of the moon's orbit will be the least, and its orbit at that point will be the nearest approach to that of a circle. But, as we have already seen, as soon as the earth leaves this part of its orbit, and begins to get nearer to the sun, it passes into a part of the aetherial medium possessing greater kinetic energy, with the result that its own velocity is accelerated. Now what is the effect of this increased acceleration of the earth on the eccentricity of the orbit of the moon?
The earth's rotation on its axis remains unaltered during this increasing orbital velocity, consequently the aetherial currents generated by the earth will remain uniform, and the moon will still be circled round the earth in the same period of about 28 days. But whilethe time of the moon's revolution remains unaltered, the orbit that she has to describe is now increased owing to the increased orbital velocity of its central body, with the result, that by the time the earth gets to that part of its orbit represented by pointD, it is then two millions of miles nearer to the sun than at pointC, and will be circled round the sun by the aetherial currents at a much greater rate. Therefore, the eccentricity of the moon's orbit is increased just in proportion to the increased velocity of the earth in its orbit round the sun. By the time the earth has arrived at pointA, when it is only a distance of about 91 millions of miles from the sun, it reaches the minimum distance, and is circled round at the decreased distance with its maximum velocity.
At this point, therefore, the eccentricity of the orbit of the moon will be at its greatest, and, if one revolution could be represented by an ellipseE G H, then that ellipse would be more elongated, and the difference between the two axes of the moon's orbit would be greater than at any other point of the earth's orbit.
Thus it can readily be seen that the eccentricity of the moon's orbit is primarily due to the different velocities of the central body, in this case the earth, as that body is carried round its central body, the sun. Where the earth's motion is slowest, there the eccentricity of the moon's orbit will be at a minimum; but where the earth's velocity is greatest, there the eccentricity of the moon's orbit will be at a maximum.
Between this minimum and maximum velocity of the earth in its orbit there is the constant increase or decrease in the eccentricity of the orbit of the moon; the eccentricity increasing as the orbital velocity of the central body increases, and decreasing as the orbital velocity of the earth decreases. A further fact has, however, to be taken into consideration, which is that the primary body about which the moon revolves is itself subject to the same eccentricity of its orbit, and for similar reasons, as we shall see later on. So that when the eccentricity of the earth's orbit is at its greatest, then the moon's orbit will possess its greatest possible eccentricity, and as the eccentricity of the earth's orbit is dependent upon the orbital velocity of the sun, so the greatest possible eccentricity of the moon's orbit is indirectly connected and associated with the sun's motion through space, which motion will now be considered.
Art. 107.The Sun and Kepler's First Law.--We have learned in the previous articles that Kepler's Laws not only apply to planetary motion, but are equally applicable to the motion of all satellites as they revolve round their respective planets.
The question now confronts us, as to whether Kepler's Laws are equallytrue in their application to the sun? Now the sun is one of the host of stars that move in the vast infinity of space, and if it can be proved that Kepler's Laws hold good in relation to one star, as they do in relation to all planets and satellites, then such a result will have a most important bearing upon the motions of other stars, and we shall be able to determine with some degree of exactness what are the motions and orbits by which all the stars in the universe are governed.
Sir Wm. Herschel first attacked the question as to whether the sun, like all the other stars, was in motion, and if in motion, what was the shape of its orbit, and the laws which governed its orbital velocity.
We know that the sun is the centre of the solar system, and the question to be considered is, whether that system is circled round a controlling centre while the sun is at rest in space, simply possessing its one axial rotation, or whether, like every planet and satellite, it is subject to two motions, an axial rotation and an orbital velocity through space. Further, if it possesses an orbital velocity through space, what is the cause of that orbital velocity?
It was due to the genius of Sir Wm. Herschel to first solve this problem, and by careful research he was able to determine that the sun, with all its attendant planets, was indeed moving through space.
Not only did he discover this fact, but he also found out the direction in which the whole of our solar system was moving, as well as the velocity with which the general movement was performed. Herschel proved that the onward march of the solar system was in the direction of the constellation of Hercules, and that the velocity of the march of this system exceeds five miles per second, or 500,000 miles per day.
Thus we learn that the whole of our solar system, comprising the sun, with all its planets with their attendant satellites which circle round each planet, and the asteroids or minor planets, are bound together by the two forces, the centripetal and the centrifugal, while the system as a whole is urged on its way by some force or power through the realms of space.
What that power is we shall try to find out as we consider the application of Kepler's Laws to this onward movement of the sun. If, then, the sun is moving through space with this enormous velocity, the question arises as to what is the shape of the path or orbit which it describes? Sir Wm. Herschel attacked this question from a mathematical standpoint, and came to a certain conclusion, as we shall see. We will, however, attack the problem solely from the philosophical standpoint, by applying to it the Rules of Philosophy given in our first chapter, andwe will then see whether our result is in harmony with the conclusions arrived at by Sir Wm. Herschel.
Now what has experience and observation to tell us regarding the orbit which any body moving in space assumes? Take, for example, our moon as illustrating the movement of all satellites, and our earth as illustrating all planetary motion.
What does observation teach us as to the orbits which these bodies describe? If it teaches us anything at all, it teaches us that every satellite and planet moves with varying velocity in a varying orbit around some central body. So far as our observation goes, then, in relation to planetary motion, or the motion of satellites, we learn that every body which moves in space fulfils Kepler's First Law, and describes an orbit round a central body, that body occupying one of the foci.
Thus, wherever we get any body moving in space, if there be any truth in philosophy which is based on experiment and observation, that body ought also to move in similar elliptic orbits, and be subject to exactly similar conditions governing those orbits. But we have learned that the sun moves through space with a velocity of about five miles per second, therefore it follows, philosophically, that the sun must also move around some other central body, and the path of such movement is that of an elliptic orbit, with the central body around which it moves occupying one of the foci.
In other words, the sun obeys the first of Kepler's Laws, the same as all the planets and satellites do. Suppose, for a moment, that it is denied that the sun moves in an elliptic orbit! What path would it pursue in place of that? Would the path be that of a straight line towards the constellation of Hercules? Such an assumption would be altogether unphilosophical, as it is contrary to all experience and observation, and is therefore untenable.
Before such an assumption can be made, it must be proved that every planet and satellite moves in a straight line, and not till that has been done can it be assumed that the sun moves in a straight line, or indeed in any other path than that stated in the first of Kepler's Laws.
This conclusion is in perfect harmony with the conclusion arrived at by Herschel, for in his work onAstronomy, in Arts. 292, 295 and 297, he points out that the sun's path is elliptic in form, and that Kepler also showed the sun fulfilled the first of his laws, and described an orbit which was in the shape of an ellipse. We have therefore philosophically arrived at the conclusion that the sun moves in an elliptic orbit, and to do so it must move round some central body, which is to the sun what the sun is to the planets, and what the planets are to the satellites.
It is impossible to conceive of the sun moving in an elliptic orbit, and yet not moving around some central body, as we should have a celestial phenomenon altogether opposed to all experience and observation. For we have already seen that the central body is just as important a factor to the elliptic orbit as the planet itself, because, without the central body there cannot possibly be any elliptic orbit. Where then in the universe is the central body around which the sun revolves? What is its distance away from the sun? What is its size? These are questions that philosophy alone cannot answer, as there is no law, so far as I can see, that regulates the size and distance of the central body in proportion to the size and distance of the planets or satellites.
If there were, then it would be possible for philosophy to apply such a law or rule. That there is a central body around which the sun revolves is as true as the fact that there is a central body about which each planet revolves, or each satellite revolves, and it remains for the practical astronomer, or the mathematician, to endeavour to discover the exact part of the heavens in which it is situated, and ascertain its distance and possibly its size. What will be the effect of the existence of this central body of the sun upon the solar system? One effect will be to do away with that isolation that up to the present has apparently existed with regard to our solar system and stellar space.
Instead of the solar system being a solitary system that moves through space subject to apparently no law, and moved by apparently no physical power, that system, through the influence and effect of the aetherial currents originated by that central body, will be linked to other parts of the universe, and will become a part of one harmonious whole, its physical connection being made manifest and plain in the self-same electro-magnetic Aether medium that forms the connecting medium between the satellites and planets, or the planets and the sun.
Another result will be, that as the sun is a star, we shall be able to apply the self-same principles and laws of Kepler to the stellar world in exactly the same way that we have done to the solar system. Thus, by bringing all stellar phenomena under the influence of Kepler's Laws, we shall be able to philosophically give an unity to the universe, and show, within rational limits, how such unity may be physically conceived, which result will be an advance upon any physical conception of the universe hitherto manifested or revealed. Further, by accepting the first of Kepler's Laws in relation to the sun, and admitting the existence of a central body, we shall be able then to apply the second of Kepler's Laws, and by so doing shall be able to give a physicalexplanation of two scientific facts which up to the present have never been physically explained, viz. the physical conception of the plane of the ecliptic, and a physical explanation of the eccentricity of the earth's orbit, which is but the result of the application of Kepler's Second Law to the sun's orbital motion around its central body.
Art. 108.The Sun and Kepler's Second Law.--We will now proceed to apply the second of Kepler's Laws to the orbital motion of the sun, and, in so doing, shall find we are able to give at the same time a physical explanation of the eccentricity of the earth's orbit.
In order to obtain a physical conception of the sun's orbital motion according to Kepler's First Law, it is essential that we should consider the effect of the existence of a central body around which the sun revolves; or, to put the matter into another form, we will ask the question as to what is the physical cause of the sun revolving round that central body?
Let us look at the case for a moment. Here, according to astronomical observation, we find a certain phenomenon which takes the form of a huge body 865,000 miles in diameter moving through space with a velocity of nearly 500,000 miles per day. What then is the physical cause of the movement of this large sphere?
Certainly there must be some physical cause, or else we have a violation of all experience, which indisputably teaches us that no body moves unless it is either pushed or pulled. We have, however, done away with a pulling power so far as the cause of the actual revolution of bodies around a central body is concerned, and in its place have substituted a medium that pushes or carries them round each central body. For over 200 years the scientific world has accepted a pulling power, that is, an attractive power, solely as the cause of the movements of celestial bodies, with the result that the physical cause of all the motions of planets and satellites has been outstanding and undiscovered.
It would, therefore, be unphilosophical to revert to the old conception of a gravitating attractive power as the sole cause of the sun's orbital motion through space. If we desire to know what is the cause of its revolution round that central body, then we must seek to find the same from the result of observation and experience in other directions.
We have learned fromArt. 102that the orbital motion of the moon is caused by the electro-magnetic Aether currents that circulate round its central body, the earth. By the same means every satellite is circled round its central body also. We have also learned fromArt. 99that the earth is carried round the sun by the circulating and rotatingelectro-magnetic Aether currents, and that these same currents also form the physical cause of the revolution of all the other planets round their central body, the sun.
Thus we arrive at the fact that wherever there is a body moving in space, it is moving solely because it is pushed along, or carried round its controlling centre by the rotating Aether currents. But we have just learned that the sun is moving through space, and that it describes an elliptic orbit around some central body in accordance with Kepler's First Law. So that the only philosophical conclusion that we can possibly arrive at in relation to the orbital motion of the sun is, that such motion is caused by similar electro-magnetic Aether currents whose circulating motion is partly caused by the rotation of that central body.
Thus we are led up to the philosophical conclusion, that it is the aetherial currents of the central body around which the sun revolves, that produce, and alone produce, the onward motion of the sun through space. Any other conclusion must be unphilosophical, and therefore untenable. We have, therefore, to conceive of the sun's central body generating and giving rise to electro-magnetic aetherial currents that extend through space to the limits at least of the solar system, and these aetherial currents, acting upon the sun's huge form by their kinetic energy, carry it with all its associated worlds through infinite space.
There is nothing extravagant in this conception, when we remember that the solar system has been moving on and on through infinite space year after year, and yet it never seems to get appreciably nearer to the other stars, but I hope to show the reason of this by strictly philosophical reasoning later on. With this conception of the sun in its relation to its central body we are now in a position to consider the application of Kepler's Second Law upon the sun's orbital motion, and its resultant effect upon the orbit of our earth and all the other planets.
From Kepler's Second Law we know that equal areas are described by the radius vector in equal times, and if the first law of Kepler is at all applicable to the sun, then it must follow that if the sun has an orbit, and moreover an elliptic orbit as stated by Kepler himself, then, as a natural result, the radius vector of the sun must move over equal areas in equal times.
The physical explanation of Kepler's Second Law was given inArt. 103, and there is no need to traverse the same ground again. It is, therefore, true that the sun moves faster in certain parts of its orbit than in others, being urged through space at its greatest velocity when it is nearest its controlling centre, and slowest when farthest away from that controlling centre.
Herschel, in his work onAstronomy, states: “The motion of the sun will be such that equal areas are thus swept over by the revolving radius vector in equal times in whatever part of the circumference of the ellipse the sun may be moving.” He, however, suggested that the earth forms a focus of the sun's ellipse, a suggestion which is unphilosophical, it seems to me, as we might equally suggest that the earth revolves round the moon, which is contrary to all observation. Thus the sun is not carried uniformly through space by the aetherial currents of its central body, because it is nearer to that central body at certain times; its velocity being regulated by its distance from that body, the same being increased as the distance is decreased, and decreased as the distance increases.
Now if this reasoning be correct, and if the sun really moves round a central body and is subject to Kepler's Second Law, then that increase and decrease of distance will be made manifest in the increase and decrease of the eccentricity of the earth's orbit.
So that if the eccentricity of the earth's orbit should vary from century to century, then we have conclusive evidence that the sun obeys the first and second of Kepler's Laws, and therefore that it revolves around a controlling centre of its own. From observation we find that this is exactly what is happening, and that at the present time the eccentricity of the earth's orbit is gradually diminishing, and in about 24,000 years the orbit will be very nearly a circle.
Now, from what was stated inArt. 106, we know that the moon's orbit will be nearly a circular orbit when the earth is farthest from the sun, and that then its orbital velocity is at a minimum.
In order for this result to be produced, the earth must reach that part of its orbit known as aphelion, where the distance from its controlling centre is greatest, so that the eccentricity of the moon's orbit is always an indication of the position of the earth in its relation to the sun. When the eccentricity of the moon's orbit is decreasing, the earth's distance from the sun is increasing, but when the eccentricity of the moon's orbit is increasing, then the earth's distance from the sun is decreasing.
Now if we apply this analogy to the eccentricity of the earth's orbit, we shall be able to obtain some idea of the relation of the sun to its central body. We find then that the eccentricity of the earth's orbit is decreasing, therefore, arguing from analogy, we arrive at the conclusion that the sun's distance from its controlling centre is increasing, and that its orbital velocity is decreasing.
If it be true that in 24,000 years the earth's orbit will be nearlycircular, then it follows that in 24,000 years the sun will be at that part of its orbit corresponding to the aphelion of the orbit of the earth, that is, its distance from its controlling centre will then be at a maximum. After that the eccentricity of the earth's orbit will begin to increase, and will continue to increase for about 40,000 years, according to some scientists, which implies that the sun will then have started from its aphelion point, so to speak, and will begin its return journey towards its central body, gradually getting nearer and nearer. As it gets nearer its orbital velocity will be proportionately increased, with the result that the eccentricity of the earth's orbit will increase also. From a consideration of the movement of the major axis of the earth's orbit, which is moving forward at the rate of 11° per year, we are told that a whole revolution will be made in 108,000 years.
We have here, then, an indication of the time that the sun takes to revolve round its central body, because the time of the whole revolution of the eccentricity of the orbit should correspond with one complete revolution of the sun around its central body. So that from a consideration of the eccentricity of the earth's orbit, we are not only able to demonstrate that the sun satisfactorily fulfils the first and second of Kepler's Laws, but, conversely, we are able to give a satisfactory physical explanation of the cause of the eccentricity of the earth's orbit, which explanation is again primarily to be found in the universal Aether medium.
Art. 109.Plane of the Ecliptic and Zodiacal Light.--As already pointed out, another phenomenon which can be physically accounted for by the sun's orbital motion through space around its central body, is that celestial plane known as the Plane of the Ecliptic.
What then is the Plane of the Ecliptic whose physical explanation we are to attempt? We know that the moon revolves round the earth as the earth revolves round the sun, while the sun is pursuing its way through space. It has been found also, that all these motions of these different bodies take place on one level, so to speak; that is to say, they do not go up or down in space, but straight on.
So straight do they move, that their path has been likened to the level of the ocean, on which a ship may sail for thousands of miles, always keeping the same level and even course. On some such ocean as this in space all the planetary systems and solar systems seem to move, ever moving on and on with the same uniformity of level through infinite space. Further, this plane of the ecliptic is to the celestial sphere what the sea-level is to the earth. The height of a mountain on the earth is stated to be so much above the sea-level.
In a similar way astronomers say that a star is a certain height above the plane of the ecliptic. What then is the physical explanation of this scientific term? We will lead up to it by first considering the effect that rotation has upon a liquid body.
It has been demonstrated that if a mass of oil is placed in a transparent liquid of the same density, so long as the oil is perfectly at rest, its shape will be that of a sphere which will float about in the liquid, but as soon as the oil is made to rotate by means of a piece of wire, then the spherical shape is changed into that of an oblate spheroid.
Further, the faster it is made to rotate, the more it will bulge out, so that its equatorial diameter will greatly exceed its polar diameter. The same principle may be illustrated by making a hoop to revolve rapidly on its axis, when a similar effect of bulging out will be produced.
Now let us apply this principle to the earth with its electro-magnetic Aether currents circulating round it, and ask what is the effect of the rotation first upon the earth, and then upon the rotating Aether currents?
It is a matter of common knowledge that the effect of rotation upon the earth when it was in a fluid state was to make its equatorial parts bulge out as it rotated, with the result that as it solidified the equatorial diameter exceeded the polar diameter by 26 miles.
If, therefore, the result of rotation upon the earth when in its fluid state was to make it spread out greater in the equatorial regions than in any other part of its surface, what must be the effect of a similar rotation upon the rotatory Aether currents? It can easily be seen that the rotation of these currents will be to make them spread out into space in a region which corresponds to the equatorial regions of the earth, so that the rotating Aether currents will be congregated more in the equatorial regions of the earth than in any other part of the earth's surface. The further also they extend into space the less depth they will have, gradually tapering off, as shown in the illustration, whereErepresents the earth andB Cthe Aether currents (Fig. 29).
Any body, therefore, situated within the sphere of their influence would be carried round the earth by the currents, and the currents would be to them their governing and controlling level.
So that the moon, which is held bound to the earth by the two opposite and equal forces, would always be carried around the earth by those electro-magnetic Aether currents, and outside of those currents it could not pass. But the earth is only 8000 miles in diameter, therefore ifthe currents gradually tapered off as suggested, by the time the aetherial currents reached the distance of the moon, their depth would not exceed 2000 or 3000 miles.
The diameter of the moon is, however, only 2160 miles, so that the rotating Aether currents would practically form an ocean in which the moon would swim, and one constant level on which it revolves in space. Wherever the earth was carried by the aetherial currents of the sun, there the aetherial currents of the earth would carry the moon, its mean distance by the conjoint working of the two co-equal forces having been permanently fixed.