Pressure being obviously the cause of planetary motion, so is it of all
terrestrial motion. To produce atomic motion and transfer generally, it
is necessary, only, that the atoms of the medium of space should be of
less size than the minutest interstices in bodies.
A universal medium must be of universal service, (as would be
conceived, were the universe involved in a medium of water,) to be
in accordance with nature's economy: to keep the planets and matter
in motion, to retain atoms together, and effect their separation
occasionally, include the whole of action required by its service; more
in this respect it cannot effect; nor is the common general procedure
otherwise effected. Therefore in pressure, by the medium of space,
consists the PRIMUM MOBILE: the beginning and end of all physical cause
of action and of all physical effect.
Pressure is nothing assumed, hypothetic, or unproven, like attraction
and gravitation,--the justly dethroned imbecile usurpers of the
imperial chair of philosophy for ages past.
On barometric evidence alone, that pressure exists all round the globe
is fully proved; and that it is indispensable to the maintenance of
the existing general order, all must readily grant who reflect for an
instant on the fatal consequences which the cessation of the general
pressure, for only a few minutes, must cause. Hence it is no immediate
question how the general pressure originated, how maintained, what
the confining boundaries or _point d'appui_. Most likely it is the
consequence of the motion of the planets themselves, surging through
the ocean of space. As every performance of nature has some ulterior
object in view, it is probable that the effect of the motion of a
planet on the medium of space is tributary to the motion of another
planet, and that the motion of the whole is a means of preventing
the cessation of motion of any of the parts. Most likely the medium
of space was not in a state of pressure at first; that planetary
motion, however commenced, effected the state of pressure necessary
for its continuance, and which would be useless beyond the precincts
of planetary evolution: where pressure is not needed, of a certainty
there is none. Hence the conclusion is warrantable, that the general
pressure, however commenced, is maintained by not only the motion of
the planets individually but in systems, through the ocean of space.
The earth may be said to swim through the medium of space, and to be
soaked with it as a submerged sponge is with water, and the portion
within the globe of the earth, is continuous with the like medium in
space generally. By which all parts of the interior of the globe are
under the general pressure equally as the surface, and all terrestrial
bodies subject to its vicissitudes.
By such means, only, is the great earthquake to be accounted for on
dynamic principles. Far as the subterraneous grumbling extends, the
physical cause must be present, and in a state of force equal to the
awful result. No pent-up air suddenly set free, or suddenly exploded
gas,--both naturally forceless,--subject to attenuation and obstruction
in the passage from the source--is competent to burst the globe and
hurl whole cities into the engulfing chasm: nor is fire any assistant,
judging from the absence of flame, smoke, cinders, and ashes. Dreadful
as is the catastrophe, it is but a natural casuality and in perfect
accordance with the laws of matter. An extraordinary rushing into the
body of the earth of medium of space, preceded by an equal efflux of
elementary matter atmospherically induced, are the cause and promoting
means of the extraordinary, terrific phenomenon.
All things being under the general pressure, and elementary atoms
of all sizes everywhere present, the interstices of bodies cannot
remain empty. From all interstices being formed by spherical atoms,
and the atoms of the medium of space the smallest, there are always
interstitial spaces for medium of space to enter, pass through or
remain within, and which _is not insulated_, but continuous with the
outward source. Thus, has the medium of space access to every atom, and
by the pressure from without, is enabled to act _centrifugally_ within
the body, as a kind of back-spring against each and the whole of its
constituent atoms, to produce expansion, dissolution, and elementary
dispersion according to the medium or circumstances in which the body
may be placed. These general principles admit of repetition, in order,
that, by repeated showing, to prove their validity, against others
more generally known and adopted, although unfounded in nature, sense,
or reason.