n the formative
stages. There are vast gaps in the middle, where they ought to be
densest. Mr. Plumer, in the _Natural Science Review_, [Page 188]
says, in regard to the results of the spectroscopic revelations: "We
are furnished with distinct proof that the gases so examined are not
only of nearly equal density, but that they exist in a low state of
_tension. This fact is fatal to the nebular theory._"

In the autumn of 1876 a star blazed out in Cygnus, which promised
to throw a flood of light on the question of world-making. Its
spectrum was like some of the fixed stars. It probably blazed ont
by condensation from some previously invisible nebula. But its
brilliancy diminished swiftly, when it ought to have taken millions
of years to cool. If the theory was true, it ought to have behaved
very differently. It should have regularly condensed from gas to a
solid sun by slow process. But, worst of all, after being a star
awhile, it showed unmistakable proofs of turning into a cloud-mist--a
star into a nebula, instead of _vice versa_. A possible explanation
will be considered under variable stars.

Such are a few of the many difficulties in the way of accepting
the nebular hypothesis, as at present explained, as being the true
mode of development of the solar system. Doubtless it has come
from a hot and diffused condition into its present state; but when
such men as Proctor, Newcomb, and Kirkwood see difficulties that
cannot be explained, contradictions that cannot be reconciled by
the principles of this theory, surely lesser men are obliged to
suspend judgment, and render the Scotch verdict of "not proven."
Whatever truth there may be in the theory will survive, and be
incorporated into the final solution of the problem; which solution
will be a much grander generalization of the human mind than the
nebular hypothesis.

[Page 189]
Of some things we feel very sure: that matter was once without
form and void, and darkness rested on the face of the mighty deeps;
that, instead of chaos, we have now cosmos and beauty; and that
there is some process by which matter has been brought from one
state to the other. Whether, however, the nebular hypothesis lays
down the road travelled to this transfiguration, we are not sure.
Some of it seems like solid rock, and some like shifting quicksand.
Doubtless there is a road from that chaos to this fair cosmos.
The nebular hypothesis has surveyed, worked, and perfected many
long reach