2 JD. Kirkwood on certain Harmonies g the Solar System. 
mutual attraction of their Liga ties several concentric rings of 
vapor circulating about the s The mutual friction of the 
molecules of each ring ought to sarees some and retard others, 
until they all had acquired the same angular motion. Conse- 
the real velocities of the molecules which are further 
rom the sun ought to be greatest.”* This view has also been 
system of waves, or else of a confused multitude of ‘evolving 
Bion wi not arranged in rings and continually coming into col- 
sion with each other.” Now the physical condition of the 
pre 
rocess of separation commenced, we may suppose a continued 
succession of rings to have been thrown off in close proximity 
to each other, each revolving round the central mass in accord- 
ance with Kepler's third law.’ The result, then, of a gradual 
nite number of concentric rings, or, rather, of Pg ee plan- 
etary clades all moving in the same direc 
attraction of some of these particles, Ba anise into close 
same! to each other, would cause them to unite, “and in this 
way we may suppose the planetary Ag sy to have been first es- 
tablished. In the subjoined diagram, let S be the center of the 
solar mass; ABC and DEF the orbits ry two adjacent planetary 
nuclei, B and E; ; and H the point of equal attraction between 
hem. Let also p, p’ be particles revolving round the center, §, 
in approximate accordance with the third law of Kepler. Their 
motion is disturbed by the attraction of H, and, in consequence, 
they finally coalesce with it. But the orbital velocity of p is 
less than that of E, while, on the other hand, that of p’ is greater. 
It is obvious, therefore, that they would not approach the nu- 
cleus in lines normal to its stirfane: The point of contact of the 
outer catgh would be behind the center, that of the inner one 
in advance of it. ese particles, then, ‘would act as oblique 
oe aoe fee Harte’s Translation, vol. ii, p. 3 
ce s Astr. Wa taaepe ii, No. 1, Mey 2d, 1851; ok ii, No. 3, June 16th, 
Vy oad wok be Weed ‘Bth, 1855, Also, Maxwell's Essay on the Stability 
ek imperty represent the motions of the 
