Art. 123. The Universe.--In the preceding chapters we have endeavoured to deal with some of the principal phenomena that help to give a mechanical conception to the entire Universe.

It now remains for us to show, in this last chapter, how, underlying all the physical structure of the Universe, there is one fundamental and primordial medium, in which all the forms of matter and motion find their ultimate unity.

The Universe literally means one ultimate whole, though that whole may be compounded of many parts, the very essence of the term embodying the idea of a complete unity which runs throughout its whole physical structure.

Apart from some such hypothesis as will be suggested in this chapter, that ultimate unity is incapable of a physical or mechanical conception. In [Art. 29] we learned that the Universe was composed of two classes of things, matter and motion, while in [Art. 30] we learned that the sum total of matter according to the law of the conservation of matter ever remains the same; while further, in [Art. 53], according to the law of the conservation of energy, the sum total of energy ever remains the same. We have also learned that the two are indissolubly united, so that wherever we found matter, whether that matter was in its atomic, molecular, planetary or stellar form, there, as its necessary complement and counterpart, was the ever-present and unceasing motion, in one or other of its many forms. Thus, throughout the entire Universe, we find the same two essentials ever working in unison and harmony.

Nowhere in the realm of infinite space is there such a phenomenon as rest or absolute death. The ideal that seems to be the key of the Universe, is that continuity of motion which science teaches us is so inseparably connected with all matter. Grouped, however, here and there throughout the Universe are modifications of this aetherial matter, termed molecules, satellites, planets, suns, or stars, which modifications are, however, not so real and abiding as the electro-magnetic Aether from which they receive their physical origin.

The physical character of the universe is progressive. Even in its ultimate unity there is no such thing as stagnation or standing still; for, while in some parts of the Universe new stars and suns and planets, yea, even new systems are being evolved out of the primordial Aether, in other parts of the Universe old stars and suns, with all their attendant planets and satellites, are passing on towards that final end, when they themselves will be again resolved into the original form of matter from which they were first made. This assertion is in perfect harmony not only with science, but also with revelation. For even revelation teaches us that all the stars shall grow old as doth a garment, and as a vesture shall they be folded up (Heb. i. 11), and that (out of their ruins) a new heaven and a new earth shall be created and the former shall not be remembered (Isaiah lxv. 17).

Thus amid all the modifications of that which is the real physical basis of all matter, we find indissolubly associated with each and all of the varied forms and modifications certain motions which are analogous to each other. In the aetherial atom itself, so infinitesimal in its proportions that even our imagination is almost strained in our attempt to conceive it, yet even here we have rotation and translation in an orbit, such rotation and translation being due to the motions of the electro-magnetic Aether. Then in the gaseous forms of matter into which these atoms may be condensed, we find the same two essentials, of matter and motion, of rotation and translation in an orbit, always working harmoniously together, through the motions of the selfsame Aether, which gives rise to the attraction and repulsions of the atoms.

Then following the principle into the planetary world, and taking the planet Saturn with its ring of satellites as an example, we find again the same two factors ever working in unison and in harmony, with their incessant rotation and translation in an orbit, forming a complete and perfect unity in themselves, such unity being due to the pressures and tensions of the Aether combined with its rotatory character. Then going a step further, we find a number of planets, with or without satellites, all rotating around one central body, that rotation and translation again being due to the motions of the rotating electro-magnetic Aether, combined with its pressures and tensions.

For millions of years, so far as we can tell, this solar system of ours has been moving through space as one complete unit.

Then out in stellar space there are millions of such systems, each distinct and perfect in themselves, each of which is made up of exactly similar parts to our solar system, these innumerable systems being doubtless joined together by the same electro-magnetic Aether, forming one larger and grander unity, known as a constellation. Then these constellations, increasing in their number, are again joined together, and form a still larger unity called a Galaxy; and galaxy being joined to galaxy, constellations to constellations, we get such an ocean of suns and stars like that known as the Milky Way, the ultimate whole revealing in all its beauty and harmony the unison of the two essentials of matter and motion. It may even be that all the oceans of suns and stars, that exist in far-off space, are joined together by one common bond, the universal electro-magnetic Aether by its two complementary motions, the centripetal and the centrifugal, the whole forming one ultimate unity which we call the Universe, having for its centre one common point or central orb, which indeed forms the centre of gravity of the entire Universe.