The ultimate root-matter as seen at our level is what scientists call the æther of space. [This has been described in Occult Chemistry under the name of koilon.] To every physical sense the space occupied by it appears empty, yet in reality this æther is far denser than anything of which we can conceive. Its density is defined by Professor Reynolds as being ten thousand times greater than that of water, and its mean pressure as seven hundred and fifty thousand tons to the square inch.

This substance is perceptible only to highly developed clairvoyant power. We must assume a time (though we have no direct knowledge on this point) when this substance filled all space. We must also suppose that some great Being (not the Deity of a solar system, but some Being almost infinitely higher than that) changed this condition of rest by pouring out His spirit or force into a certain section of this matter, a section of the size of a whole universe. This effect of the introduction of this force is as that of the blowing of a mighty breath; it has formed within this æther an incalculable number of tiny spherical bubbles, [The bubbles are spoken of in The Secret Doctrine as the holes which Fohat digs in space.] and these bubbles are the ultimate atoms of which what we call matter is composed. They are not the atoms of the chemist, nor even the ultimate atoms of the physical world. They stand at a far higher level, and what are usually called atoms are composed of vast aggregations of these bubbles, as will be seen later.

When the Solar Deity begins to make His system, He finds ready to His hand this material—this infinite mass of tiny bubbles which can be built up into various kinds of matter as we know it. He commences by defining the limit of His field of activity, a vast sphere whose circumference is far larger than the orbit of the outermost of His future planets. Within the limit of that sphere He sets up a kind of gigantic vortex—a motion which sweeps together all the bubbles into a vast central mass, the material of the nebula that is to be.

Into this vast revolving sphere He sends forth successive impulses of force, gathering together the bubbles into ever more and more complex aggregations, and producing in this way seven gigantic interpenetrating worlds of matter of different degrees of density, all concentric and all occupying the same space.

Acting through His Third Aspect He sends forth into this stupendous sphere the first of these impulses. It sets up all through the sphere a vast number of tiny vortices, each of which draws into itself forty-nine bubbles, and arranges them in a certain shape. These little groupings of bubbles so formed are the atoms of the second of the interpenetrating worlds. The whole number of the bubbles is not used in this way, sufficient being left in the dissociated state to act as atoms for the first and highest of these worlds. In due time comes the second impulse, which seizes upon nearly all these forty-nine bubble-atoms (leaving only enough to provide atoms for the second world), draws them back into itself and then, throwing them out again, sets up among them vortices, each of which holds within itself 2,401 bubbles (49^2). These form the atoms of the third world. Again after a time comes a third impulse, which in the same way seizes upon nearly all these 2,401 bubble-atoms, draws them back again into their original form, and again throws them outward once more as the atoms of the fourth world—each atom containing this time 49^{3} bubbles. This process is repeated until the sixth of these successive impulses has built the atom of the seventh or the lowest world—that atom containing 49^{6} of the original bubbles.

This atom of the seventh world is the ultimate atom of the physical world—not any of the atoms of which chemists speak, but that ultimate out of which all their atoms are made. We have at this stage arrived at that condition of affairs in which the vast whirling sphere contains within itself seven types of matter, all one in essence, because all built of the same kind of bubbles, but differing in their degree of density. All these types are freely intermingled, so that specimens of each type would be found in a small portion of the sphere taken at random in any part of it, with, however, a general tendency of the heavier atoms to gravitate more and more towards the centre.

The seventh impulse sent out from the Third Aspect of the Deity does not, as before, draw back the physical atoms which were last made into the original dissociated bubbles, but draws them together into certain aggregations, thus making a number of different kinds of what may be called proto-elements, and these again are joined together into the various forms which are known to science as chemical elements. The making of these extends over a long period of ages, and they are made in a certain definite order by the interaction of several forces, as is correctly indicated in Sir William Crookes's paper, The Genesis of the Elements. Indeed the process of their making is not even now concluded; uranium is the latest and heaviest element so far as we know, but others still more complicated may perhaps be produced in the future.

As ages rolled on the condensation increased, and presently the stage of a vast glowing nebula was reached. As it cooled, still rapidly rotating, it flattened into a huge disc and gradually broke up into rings surrounding a central body—an arrangement not unlike that which Saturn exhibits at the present day, though on a far larger scale. As the time drew near when the planets would be required for the purposes of evolution, the Deity sets up somewhere in the thickness of each ring a subsidiary vortex into which a great deal of the matter of the ring was by degrees collected. The collisions of the gathered fragments caused a revival of the heat, and the resulting planet was for a long time a mass of glowing gas. Little by little it cooled once more, until it became fit to be the theatre of life such as ours. Thus were all the planets formed.

Almost all the matter of those interpenetrating worlds was by this time concentrated into the newly formed planets. Each of them was and is composed of all those different kinds of matter. The earth upon which we are now living is not merely a great ball of physical matter, built of the atoms of that lowest world, but has also attached to it an abundant supply of matter of the sixth, the fifth, the fourth and other worlds. It is well known to all students of science that particles of matter never actually touch one another, even in the hardest of substances. The spaces between them are always far greater in proportion than their own size—enormously greater. So there is ample room for all the other kinds of atoms of all those other worlds, not only to lie between the atoms of the denser matter, but to move quite freely among them and around them. Consequently, this globe upon which we live is not one world, but seven interpenetrating worlds, all occupying the same space, except that the finer types of matter extend further from the centre than does the denser matter.

We have given names to these interpenetrating worlds for convenience in speaking of them. No name is needed for the first, as man is not yet in direct connection with it; but when it is necessary to mention it, it may be called the divine world. The second is described as the monadic, because in it exist those Sparks of the divine Life which we call the human Monads; but neither of these can be touched by the highest clairvoyant investigations at present possible for us. The third sphere, whose atoms contain 2,401 bubbles, is called the spiritual world, because in it functions the highest Spirit in man as now constituted. The fourth is the intuitional world, [Previously called in Theosophical literature the buddhic plane.] because from it come the highest intuitions. The fifth is the mental world, because from its matter is built the mind of man. The sixth is called the emotional or astral world, because the emotions of man cause undulations in its matter. (The name astral was given to it by mediæval alchemists, because its matter is starry or shining as compared to that of the denser world.) The seventh world, composed of the type of matter which we see all around us, is called the physical.