s scarcely necessary to point out that a planet
turning an invariable face to the sun rotates in the same direction in
which it revolves, and in the same period. As, with the progress of
condensation, tides became feebler and rotation more rapid, the
accelerated spinning necessarily proceeded in the sense thus prescribed
for it. Hence the backward axial movements of Uranus and Neptune may
very well be a survival, due to the inefficiency of solar tides at their
great distance, of a state of things originally prevailing universally
throughout the system.

The general outcome of Mr. Darwin's researches has been to leave
Laplace's cosmogony untouched. He concludes nothing against it, and,
what perhaps tells with more weight in the long run, has nothing to
substitute for it. In one form or the other, if we speculate at all on
the development of the planetary system, our speculations are driven
into conformity with the broad lines of the Nebular Hypothesis--to the
extent, at least, of admitting an original material unity and motive
uniformity. But we can see now, better than formerly, that these supply
a bare and imperfect sketch of the truth. We should err gravely were we
to suppose it possible to reconstruct, with the help of any knowledge
our race is ever likely to possess, the real and complete history of our
admirable system. "The subtlety of nature," Bacon says, "transcends in
many ways the subtlety of the intellect and senses of man." By no mere
barren formula of evolution, indiscriminately applied all round, the
results we marvel at, and by a fragment of which our life is
conditioned, were brought forth; but by the manifold play of interacting
forces, variously modified and variously prevailing, according to the
local requirements of the design they were appointed to execute.

FOOTNOTES:

[Footnote 1150: _Exposition du Systeme du Monde_, t. ii., p. 295.]

[Footnote 1151: In later editions a retrospective clause was added
admitting a prior condition of all but evanescent nebulosity.]

[Footnote 1152: _Mec. Cel._, lib. xiv., ch. iii.]

[Footnote 1153: _Beitraege zur Dynamik des Himmels_, p. 12.]

[Footnote 1154: _Trans. Roy. Soc. of Edinburgh_, vol. xxi., p. 66.]

[Footnote 1155: Newcomb, _Pop. Astr._, p. 521 (2nd ed.).]

[Footnote 1156: M. Williams, _Nature_, vol. iii., p. 26.]

[Footnote 1157: _Comp. Brit. Almanac_, p. 94.]

[Footnote 1158: Radau, _Bull. Astr._, t. ii., p. 316.]

[Footnote 1159: Newcomb