“3. OF THE SEVEN (ELEMENTS) – FIRST ONE MANIFESTED, SIX CONCEALED; TWO MANIFESTED, FIVE CONCEALED; THREE MANIFESTED, FOUR CONCEALED; FOUR PRODUCED, THREE HIDDEN; FOUR AND ONE TSAN (FRACTION) REVEALED, TWO AND ONE HALF CONCEALED; SIX TO BE MANIFESTED, ONE LAID ASIDE.
LASTLY, SEVEN SMALL WHEELS REVOLVING, ONE GIVING BIRTH TO THE OTHER.
Although these stanzas refer to the whole Universe after a Maha-pralaya (universal destruction), yet this sentence, as any student of Occultism may see, refers also by analogy to the evolution and final formation of the primitive (though compound) Seven Elements on our Earth.
Of these, four elements are now fully manifested, while the fifth – Ether – is only partially so, as we are hardly in the second half of the Fourth Round, and consequently the fifth-Element will manifest fully only in the Fifth Round.
These “Seven Wheels” are our planetary chain. By “Wheels” the various spheres and centers of forces are generally meant; but in this case they refer to our septenary ring.”
H. P. Blavatsky