it is empty space. There is not one finger's breadth of void space in the
whole boundless universe."[21] "The mother-substance" is said, in this
treatise, to produce this æther of space as its seventh grade of density,
and all objective suns are said to have this for their "substance."

To any power of sight which we can bring to bear upon it, this koilon
appears to be homogeneous, though it is probably nothing of the kind, since
homogeneity can belong to the mother-substance alone. It is out of all
proportion denser than any other substance known to us, infinitely
denser--if we may be pardoned the expression; so much denser that it seems
to belong to another type, or order, of density. But now comes the
startling part of the investigation: we might expect matter to be a
densification of this koilon; it is nothing of the kind. Matter is not
koilon, but _the absence of koilon_, and at first sight, matter and space
appear to have changed places, and emptiness has become solidity, solidity
has become emptiness.

To help us to understand this clearly let us examine the ultimate atom of
the physical plane (see pp. 21-23). It is composed of ten rings or wires,
which lie side by side, but never touch one another. If one of these wires
be taken away from the atom, and be, as it were, untwisted from its
peculiar spiral shape and laid out on a flat surface, it will be seen that
it is a complete circle--a tightly twisted endless coil. This coil is
itself a spiral containing 1680 turns; it can be unwound, and it will then
make a much larger circle. This process of unwinding may be again
performed, and a still bigger circle obtained, and this can be repeated
till the seven sets of spirillæ are all unwound, and we have a huge circle
of the tiniest imaginable dots, like pearls threaded on an invisible
string. These dots are so inconceivably small that many millions of them
are needed to make one ultimate physical atom, and while the exact number