388 WARREN UPHAM, M.A., F.G.S.A., ON THE NEBULAR AND 



6. The plane of the planets' rotation nearly coincides uith 



that of the orbits. 



7. The direction of the rotation is the same as that of the 



orbital revolution, excepting probably the two outer- 

 most planets. 



8. The plane of orbital revolution of the satellites is nearly 



coincident with that of the planet's rotation. 



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 condition 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. Kiehard A. Proctor, after stating the physical 



* The Meteoritic Hypothesis, a Statement of the Results of a Spectroscopic 

 Inquiry into the Origin of Cosmical Systems. 1890, p. 322, 



