ng greater than that outside. Now in accordance with our second
Rule of Philosophy, if experience is to be any guide at all, then it
most conclusively teaches us that the Aether being subject to the same
laws as the atmosphere, the same results inevitably follow. Therefore
the Aether nearest the earth is denser than any layer immediately above
it, and that layer denser than the one above it, and so on for great
distances, with the result that the only conclusion we can come to in
regard to the density and rarity of Aether in relation to all
gravitating bodies is, that the densest part of the Aether is nearest to
them, and the rarest, the farthest away from them. So that while
Newton's suggestion in his nineteenth query is correct in principle, it
is incorrect in application to space.

I would like to point out here, that what is true of the earth in
relation to the density of the surrounding Aether, must also be true,
according to our second Rule of Philosophy, of every other planet, or
sun, or star. So that every planet, satellite, every sun or star has its
atmosphere, if I may so term it, of Aether, which obeys and follows the
same laws as the earth's atmosphere does.

This is a most important fact, and has a most important bearing upon the
physical cause of Gravitation as applied to each planet, and sun and
star, as I shall afterwards show.

I wish now to bring the reader into contact with a Theory of Gravitation
that was given to the world by Professor Challis of Cambridge, 1872. In
the _Philosophical Magazine_ of June of that year he writes: "I assume
that all the active forces of Nature are different modes of pressure
under different circumstances of a universal elastic Aether, which
presses always proportionately to its density."

Now what I wish to point out is, that while Prof. Challis admits the
density of the Aether, and also varying degrees of density, as he states
that the Aether presses proportionately to the density, he does not show
how that varying density is accounted for. If there is this varying
density, then there must be some underlying principle which governs the
variation in density, and I know of only one principle or law which can
regulate that variation in density, and that is that Aether is
gravitative, and being gravitative it not only possesses density, but
also variations in density.

Thus by admitting that Aether is gravitative, because it is matter, we
have at once a satisfactory ex