m, and is thus in marked
contrast with any portion of ether, for the latter could not be
identified in a similar way. One may therefore say that the ether is
formless.

6. MATTER IS GRAVITATIVE.

The law of gravitation is held as being universal. According to it every
particle of matter in the universe attracts every other particle. The
evidence for this law in the solar system is complete. Sun, planets,
satellites, comets and meteors are all controlled by gravitation, and
the movements of double stars testify to its activity among the more
distant bodies of the universe. The attraction does not depend upon the
kind of matter nor the arrangement of molecules or atoms, but upon the
amount or mass of matter present, and if it be of a definite kind of
matter, as of hydrogen or iron, the gravitative action is proportional
to the number of atoms.

THE ETHER IS GRAVITATIONLESS.

One might infer already that if the ether were structureless, physical
laws operative upon such material substances as atoms could not be
applicable to it, and so indeed all the evidence we have shows that
gravitation is not one of its properties. If it were, and it behaved in
any degree like atomic structures, it would be found to be denser in the
neighbourhood of large bodies like the earth, planets, and the sun.
Light would be turned from its straight path while travelling in such
denser medium, or made to move with less velocity. There is not the
slightest indication of any such effect anywhere within the range of
astronomical vision.

Gravitation then is a property belonging to matter and not to ether.
The impropriety of thinking or speaking of the ether as matter of any
kind will be apparent if one reflects upon the significance of the law
of gravitation as stated. Every particle of matter in the universe
attracts every other particle. If there be anything else in the universe
which has no such quality, then it should not be called matter, else the
law should read: Some particles of matter attract some other particles,
which would be no law at all, for a real physical law has no exceptions
any more than the multiplication table has. Physical laws are physical
relations, and all such relations are quantitative.

7. MATTER IS FRICTIONABLE.

A bullet shot into the air has its velocity continuously reduced by the
air, to which its energy is imparted by making it move out of its way. A
railway train is brought to rest by the friction b