4 
28 D. Trowbridge on the Nebular Hypothesis. 
case. For long waves, the resultant force is in the same direc 
tion as the displacement, reaching a maximum for waves whose — 
length is about ten times the thickness of the stratum. For 
waves about five times as long as the stratum is thick, there is 
no resultant force; and for shorter waves, the force is in the op- 
a permanent ring. If they do not, short waves will arise and 
be propagated among the satellites, with ever increasing magni — 
tude, till a sufficient number of drops have been brought into — 
bodies would continue to come into collision until the conditions — 
en: ; 
* Maxwell, p, 45. * Tb, p. 64, 
