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.
There are ten schemes of evolution at present existing in our solar system, but only seven of them are at the stage where they have planets in the physical world.

These are: (1) that of an unrecognized planet Vulcan, very near the sun, about which we have very little definite information.

It was seen by the astronomer Herschel, but is now said to have disappeared.