358 D. Trowbridge on the Nebular Hypothesis. 
abandoned, such ring would be of considerable width, greater, 
very probably, than that of any other ring. We are thus able 
account, in a yery satisfactory way, for Prof. Kirkwood’s 
“spheres of attraction,” in his beautiful ‘ Analogy.” 
nearest and most distant planet. But in consequence of the 
want of a perfectly symmetrical distribution of the materials 
composing the primitive spheroid, we should not look for an ob- 
vious law regulating the distribution of the masses of the several 
planets thus formed. It is sufficient to find that the planets 
gradually increase in mass as they are situated farther from the 
sun, until we arrive at the greatest mass, and thence a gradual 
rease. 
_ 80. If the materials composing the rings were so distributed 
as to cause a greater amount to be detached from one side of the 
— of the equator of the spheroid, than from the other side, 
t would cause a change in the direction of the axis of rotation 
__ @f the revolving body, and thus the second ring might be 
Somewhat inclined to the first. For a similar reason the third 
ught differ in inclination from the first and second; and so on 
