suggestive point of view, from which it claims a further and a special consideration.

According to this distinguished physicist, the sun and the heat of the sun were produced some millions of years ago by the fall together of its materials from a state of wide diffusion, as a cloud of stones and dust and gaseous matter. The shock of its atoms, and the mutual collision of its smaller constituent bodies and masses under the action of gravitation, gradually warmed and lit up the nebulous mass, while the final rush together of the whole immense materials with prodigious velocities resulted, by the law of the convertibility of energy, in a vast development of heat in a single condensed mass, which formed the sun.

In like manner, the fall together of the earth's materials millions of years ago, produced the earth at first at white heat, like the sun; but as the earth's constituents fell in smaller quantity, from less distances, and with consequent less velocities, the amount of heat, though great, was far less than in the case of the sun. Accordingly, the earth cooled down long since, while the sun, though lavishly spending heat from the beginning, will not be reduced to the earth's temperature for millions of years to come.

In the same way, our moon and all the other planets, with their moons, were produced-the meteoric showers and the comets, probably of meteoric composition, still existing to remind us of the like former condition of all the other bodies of the solar system.

Such is the theory of Thomson respecting the origin of the sun and planets. But there is no mention here of rings of vapour, and in other respects we are a good way from the theory of Laplace. It is, in fact, so far, a different and a better hypothesis. It explains the sun's heat, which was

assumed by Laplace; and it explains it by a true scientific cause the impact of masses in motion. Moreover, by a still bolder application of the same conception, and for the first time, we might almost say, since men began to speculate on the matter, it explains in a real way, the actual presence of our old solid earth here in space to-day. It is true that the explanation given-the sudden convergence from the four winds of the materials of our globe-is at first a little startling, and almost as trying to the imagination as the old theory of creation ex nihilo. But on reflection we see that the thing is possible, the conception scientific. If we believe our earth to be a globe in space, we must allow that its materials, as well as those of every other heavenly body, may have come thus together from a state of nebular or meteoric dispersion, under the strong compulsion of gravitation; and it may have even been, as Professor Tait suggests, "that they fell together in such a way that the whole mass of the earth was agglomerated together almost at once."

We might, I say, even believe in this instantaneous fusion and chemical union following on the mechanical forcing together of the materials, since the chemical change, on the vast scale of a given mass of loose materials into a molten planet, may be quite as easy for Nature to effect as the chemical changes on the small scale in her ordinary operations. It is only when we ask the inevitable further question-Whence came the materials that thus suddenly met together one day for the composition of our globe ?—that the theory begins to prove unsatisfactory. For it appears from Sir W. Thomson's expositor, Professor Tait, that the precipitated substances came from, or rather formerly composed, a smaller nebulous cloud that had become severed

from the primitive mass before its main body had finally
condensed into the sun. But how severed? is still the
question, and that which raises the old difficulty. The fall
together of the parts of a scattered nebulous cloud we
understand, and admit as a possible explanation of the sun
and planets; but, precisely for that reason, the fall asunder
of the primitive nebulous mass is difficult to understand,
and cannot be allowed as an explanation of the separate
masses required to compose the earth and planets, with their
numerous moons. It cannot be allowed, at least, until some
natural force is pointed out sufficiently powerful to produce
the separation in opposition to the strong force of gravity
drawing the mass ever closer together by hypothesis. No
matter how loosely associated the constituents of the original
nebulous cloud, in order to break off parts from it (since no
original repulsive force is postulated) it must be shown that
some such force, centrifugal or other, would be generated
within the mass.
Nor would this be sufficient. It must be
further shown how such a force disintegrated the nebula so
skilfully, and gave the transported parts at the moment of
projection such precise velocities and in such directions, that,
avoiding the other contingencies of the case-of passing
off finally into infinite space or describing paths returning
on the mass-they have been ever since moving in nearly
circular orbits around it.

It must be shown, in short, that all was provided for by law, and that nothing was left to chance, especially at the supreme moment when our earth was cast off. Until this has been shown more satisfactorily than has yet been done, though we may entertain ourselves with the speculation that the earth and planets were formerly nebulous islands floating in space, we shall yet hesitate to believe in their

1

alleged former connection with the mainland of the sun's nebular continent, and all the more when we reflect that the former existence of the islands themselves is not beyond the reach of doubt.

To conclude: we know nothing for certain respecting the mode of origination of the earth, the sun, the planets, the stars. We believe, on the showing of Science, that the sun could not have existed from eternity, because his heat is a limited quantity that could not have lasted perpetually unless recruited from sources of which Science has no knowledge. But still, there may now be, and there may have been, such sources. Nor could we be certain to the contrary, unless we were assured that we know all the physical forces in nature, and that none of these, either separately or by their conjoint action, could have kept up an eternal supply of solar heat. Assuming, however, as more probable, that the sun has not existed from eternity, we are sure that he gathered his fires by natural causes. But we are not sure that the only cause was the impact of falling masses of matter, or the condensation of his diffused matter into closer

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compass, as Helmholtz has it. And assuming that the sun aje had a beginning in time, we are equally sure that the earth ene had also a beginning, since it could not well have existed in the sun's absence. But we are not sure that the earth (any st more than the sun) was formed at white her by th

rushing together of its materials, much less

solidified result of a prodigious ring of var

ages ago from a revolving vaporous its contracting and cooling down t

Both these hypotheses should respect that is due to the guess however scientifically prompt

ON THE CREATION AND GOD.

15

however superior to the rude cosmogonies of non-scientific ages that we now dismiss as only fit for children, they are only guesses. They are only attempts at the solution of the problem-being given a world or a system of worlds, to determine how they were made; a problem so transcendent that the highest human solutions may be no more than rude approximations. And all real verification is out of the question; since, however true our theory of the past, pronon of construction, a competing and more plausible theory is, we see, always possible; while, if worlds are now any where made in stellar space according to our formula, it, in still impossible to prove the fact, owing to the remote the phenomenon. We must not, then, with some, treat the nebular hypothesis in either of its forms as if it contained the whole truth which explained fully and fray the process of world-making. We must not erect it into an rticle of scientific faith with the physicists and geogra - make it an integral part of our philosophic systerns with e evolution philosophers like Strauss and Herbert Spencer. e are simply to consider the two forms of the hypothesis conjectures equal in poetic grandeur, but unequal in ntific credit-of the phenomena

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panied the first planets as Zobes ain proportion of misleading even

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