notion that the sun and
earth are solidifying and cooling down, as explanatory of the facts
revealed by astronomy and geology, infers the very contrary from the
acknowledged facts, namely, that we are coming up to the nebular
condition, rather than developing from it. He writes as follows:

"The earth is progressing by excessively slow changes toward
the solar and nebulous condition. Its history is a repetition
of the solar, and a time must arrive when the surface,
becoming incandescent, will be obscured only by casual dark
pits in a brilliant atmosphere, a _souvenir_ of the present
darkness of the crust; yet during a certain period, within
fixed limits of gravitating force and heat of mass, the human
race may continue to exist; progressing, we may suppose, in
force and fineness of organization. The race will perish,
perhaps, in the order of nature, by failure or insufficient
number of offspring, a principal cause of the extinction of
superior races. The earth must become lone and voiceless long
before the incandescence of the crust. Science may follow it
into the condition of an attendant star, and then of an
expanding nebula.

"In the cosmos all movements are cyclical, and recurrent,
without change, save interchange among forms of motion. A
universe which is, in its total, the same to-day as yesterday,
and always, would appear idle and dull if it were not the
footstool of divine force, upon which the creative will
maintains a certain equipoise, necessary to the continued
production of spiritual forms."

_It is an impracticable notion, contrary to the first principle of
mechanics, that action and reaction are equal._

The grand requirement of the system--power to work the engine--can never
be raised by La Place's, nor by any other mechanical plan. The cooling
cloud of fire-mist is simply a very big machine, and no machine can
generate power to work itself. If La Place could have somehow or other
got power for the motion of rotation outside of his cloud, he might have
made it revolve, and scatter off great lumps of the lightest outside
stuffs, as your grindstone scatters off drops of water when you turn it
rapidly; but, having no such power, his theory is a plan to make the
grindstone turn itself. It is, therefore, precisely of the same value
as any one of the hundred of ingenious schemes for creating powe