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.  We at first understood that it was in its third incarnation; but it is now regarded as possible that it has recently passed from its fifth to its sixth chain, which would account for its alleged disappearance; (2) that of Venus, which is in its fifth incarnation, and also therefore, has only one visible globe; (3) that of the Earth, Mars and Mercury, which has three visible planets because it is in its fourth incarnation; (4) that of Jupiter, (5) that of Saturn, (6) that of Uranus, all in their third incarnations; and (7) that of Neptune and the two unnamed planets beyond its orbit, which is in its fourth incarnation, and therefore has three physical planets as we have.

In each incarnation of a chain (commonly called a chain-period) the wave of divine Life moves seven times round the chain of seven planets, and each such movement is spoken of as a round.  The time that the life-wave stays upon each planet is known as a world-period, and in the course of a world-period there are seven great root-races.  As has been previously explained, these are subdivided into sub-races, and those again into branch-races.  For convenience of reference we may state this in tabular form: 

7 Branch-Races           make   1  Sub-Race
7 Sub-Races              make   1  Root-Race
7 Root-Races             make   1  World-Period
7 World-Periods          make   1  Round
7 Rounds                 make   1  Chain-Period
7 Chain-Periods          make   1  Scheme of Evolution
10 Schemes of Evolution  make   1  Our Solar System

It is clear that the fourth root-race of the fourth globe of the fourth round of a fourth chain-period would be the central point of a whole scheme of evolution, and we find ourselves at the present moment only a little past that point.  The Aryan race, to which we belong, is the fifth root-race of the fourth globe, so that the actual middle point fell in the time of the last great root-race, the Atlantean.  Consequently the human race as a whole is very little more than half-way through its evolution, and those few souls who are already nearing Adeptship, which is the end and crown of this evolution, are very far in advance of their fellows.