Chase.] 184 [Apll21, 



NEBULAR ACTION IN THE SOLAR SYSTEM. 



By Pliny Earle Chase, 



professor of philosophy in iiaverford college. 



(Bead before the American Philosophical Society, April 2\st, 187G.) 



In studying the special evidences of nebular action, we find various sig- 

 nificant relations, based on the following cardinal planetary positions, for 

 •which Stockwell's* values are taken: — 



1. The minimum eccentricities of the principal planets, as found by 

 Stock well are:— Neptune, .00557; Uranus, .01176; Saturn, .01237; Jupiter, 

 .0255; Earth and Venus, each, 0. The ratios, counting towards Sun, are, 

 therefore, \|; -f- § 3= 1 : 2.11; \i : %=z\ : 2.07. The closeness of these 

 approximations to the fraction ^, suggests their probable dependence on a fall 

 through a half-radius, which would give the particles of a nebulous ring 

 the velocity of separation. 



2. The secular ranges of the planets present many suggestive features. 

 Jupiter's (.68295) corresponds with Earth's orbital radius of spherical gyra- 

 tion (.63245); Saturn's (1.6088), with the nucleal tendency of Earth's kinetic 



radius, (1.4232^ = 1.6009); Uranus's (2.99111), with the asteroidal belt, 

 and with a linear pendulum of which Earth occupies an oscillatory centre; 

 Mars's, with the centre of linear oscillation of Jupiter's; Venus's, with 

 the centre of explosive oscillation of Mercury's; the range sum of Neptune 

 and Earth, (1.00685), with Earth's mean vector-radius; of Venus and Mer- 

 cury, (.60462), With the kinetic atmosphere (.60087); the sum-ratio of 

 Earth and Venus, (.23765), with the ratio of Mercury's greatest eccentricity 

 (.23172). 



. 8. Stockwell's estimates for the maximum secular eccentricity, Bessel's 

 for the masses of Jupiter and Saturn, and Ncwcomb's for those of Uranus 

 and Neptune, give the following values for tiie positions of centres of 

 gravity, at secular perihelion, mean, and secular aphelion, the unit being 

 Sun's radius: 

 ♦Smithsonian contributions, 232. pp. 37, 38. 



