Since our evolution is centred at present upon this globe which we call the earth, it is in connection with it only that we shall be speaking of these higher worlds, so in future when I use the term "astral world" I shall mean by it the astral part of our own globe only, and not (as heretofore) the astral part of the whole solar system. This astral part of our own world is also a globe, but of astral matter. It occupies the same place as the globe which we see, but its matter (being so much lighter) extends out into space on all sides of us further than does the atmosphere of the earth--a great deal further. It stretches to a little less than the mean distance of the moon, so that though the two physical globes, the earth and the moon, are nearly 240,000 miles apart, the astral globes of these two bodies touch one another when the moon is in perigee, but not when she is in apogee. I shall apply the term "mental world" to the still larger globe of mental matter in the midst of which our physical earth exists. When we come to the still higher globes we have spheres large enough to touch the corresponding spheres of other planets in the system, though their matter also is just as much about us here on the surface of the solid earth as that of the others. All these globes of finer matter are a part of us, and are all revolving round the sun with their visible part. The student will do well to accustom himself to think of our earth as the whole of this mass of interpenetrating worlds--not only the comparatively small physical ball in the centre of it. Chapter IV THE EVOLUTION OF LIFE All the impulses of life which I have described as building the interpenetrating worlds come forth from the Third Aspect of the Deity. Hence in the Christian scheme that Aspect is called "the Giver of Life", the Spirit who brooded over the face of the waters of space. In Theosophical literature these impulses are usually taken as a whole, and called the First Outpouring. When the worlds had been prepared to this extent, and most of the chemical elements already existed, the Second Outpouring of life took place, and this came from the Second Aspect of the Deity. It brought with it the power of combination. In all the worlds it found existing what may be thought of as elements corresponding to those worlds. It proceeded to combine those elements into organisms which it then ensouled, and in this way it built up the seven kingdoms of Nature. Theosophy recognizes seven kingdoms, because it regards man as separate from the animal kingdom and it takes into account several stages of evolution which are unseen by the physical eye, and gives to them the mediæval name of "elemental kingdoms".