204 T'he American Geologist. ^i'"""- ^^^^ 
9. The direction of the satellites' revolution also 
coincides with that of the planet's rotation. 
10. The largest planets rotate most swiftly. 
That these wonderfully harmonious relations of the 
planets to each other and to the sun, and of the satellites 
to the planets, could have originated by any fortuitous 
concourse of matter, like the visits of comets which may 
come from any part of the heavens, is utterly improbable. 
There is not one chance in millions for the order of the 
solar system to have come to pass without a systematic 
development; but the sublime theory of Laplace, in its 
main outlines, with modifications as required ,by further 
knowledge of astronomical and physical laws, or some 
other nebular theory, perhaps the one most fully reviewed 
in this paper, accounts for all this majestic unity of the 
Creator's plan in launching the earth and its associate 
planets to revolve around the enormously larger central 
sun. 
Instead of an originally gaseous and very hot condi- 
tion of the parent nebula, as supposed by Laplace, some 
prominent English physicists and astronomers have 
thought that in its earliest definable condition it consisted 
of meteorites, that is, particles and little masses of solid 
and cold matter. Sir Norman Lockyer, reasoning from 
his extensive investigations in spectrum analyses, states 
this view as follows:* "Nebulae are really swarms of 
meteorites or meteoritic dust in the celestial spaces. The 
meteorites are sparse, and the collisions among them bring 
about a rise of temperature sufficient to render luminous 
some of their chief constituents." 
Besides the testimony of the spectroscope concerning 
the characters of the nebulae, we may consider the rings of 
Saturn, which are very thin but have great areal extent, as 
probably a strong evidence of the meteoritic derivation of 
the planets and the sun. Richard A. Proctor, after stating 
the physical impossibilities of the existence and perma- 
nence of these unique rings as either solid or liquid con- 
tinuous bodies, wrote :t "The sole hypothesis remains 
* The Meteoritic Hypothesis, a Statement of the Results of a Spec- 
troscopic Inquiry into the Qrlgrin of Cosmical Systems, 1890, p. 322. 
t Saturn and its System, second edition, revised, 1882, p. 135. 
