These globes are not all composed of physical matter. 4A contains no matter lower than that of the mental world; it has its counterpart in all the worlds higher than that, but nothing below it. 4B exists in the astral world; but 4C is a physical globe, visible to our telescopes, and is in fact the planet which we know as Mars. Globe 4D is our own Earth, on which the life-wave of the chain is at present in action. Globe 4E is the planet which we call Mercury--also in the physical world. Globe 4F is in the astral world, corresponding on the ascending arc to globe 4B in the descent; while globe 4G corresponds to globe 4A in having its lowest manifestation in the lower part of the mental world. Thus it will be seen that we have a scheme of globes starting in the lower mental world, dipping through the astral into the physical and then rising into the lower mental through the astral again. Just as the succession of the globes in a chain constitutes a descent into matter and an ascent from it again, so do the successive incarnations of a chain. We have described the condition of affairs in the fourth incarnation; looking back at the third, we find that that commences not on the lower level of the mental world but on the higher. Globes 3A and 3G, then, are both of higher mental matter, while globes 3B and 3F are at the lower mental level. Globes 3C and 3E belong to the astral world, and only globe 3D is visible in the physical world. Although this third incarnation of our chain is long past, the corpse of this physical globe 3D is still visible to us in the shape of that dead planet the Moon, whence that third incarnation is usually called the lunar chain. The fifth incarnation of our chain, which still lies very far in the future, will correspond to the third. In that, globes 5A and 5G will be built of higher mental matter, globes 5B and 5F of lower mental, globes 5C and 5E of astral matter, and only globe 5D will be in the physical world. This planet 5D is of course not yet in existence. The other incarnations of the chain follow the same general rule of gradually decreasing materiality; 2A, 2G, 6A and 6G are all in the intuitional world; 2B, 2F, 6B and 6F are all in the higher part of the mental world; 2C, 2E, 6C and 6E are in the lower part of the mental world; 2D and 6D are in the astral world. In the same way 1A, 1G, 7A and 7G belong to the spiritual world; 1B, IF, 7B and 7F are in the intuitional world; 1C, 1E, 7C and 7E are in the higher part of the mental world; 1D-and 7D are in the lower part of the mental world. Thus it will be seen that not only does the life-wave in passing through one chain of globes dip down into matter and rise out of it again, but the chain itself in its successive incarnations does exactly the same thing.