162 On the Continuance of Recur r'uuj Changes m the Universe. 



to the eye to be at rest. If it takes so long for the stellar masses 

 to change their mean distances, what must it be in regard to the 

 time taken to traverse their mean length of path (previous to 

 the encounters); and thus in each individual case an almost 

 limitless epoch of time is rendered possible for the conditions 

 of life, while in the collective universe that stability and per- 

 manence are ensured which can alone rest upon recurring 

 change. 



In regard to a possible objection that, as far as observation 

 has gone, the proper motion of the stars has not been found 

 to exceed 30 to 50 miles per second, it may be replied that 

 those stars whose proper motions it has been possible to esti- 

 mate roughly, constitute an insignificant and almost vanishing 

 minority compared with the rest of the visible stars, which are 

 known to be situated at immeasurable distances. It has been 

 pointed out by Dr. Croll that it would be scarcely reasonable 

 to expect luminous stars to possess a high proper motion, since 

 precisely they would have lost a greater part of their proper 

 motion in the collisions which developed the heat which ren- 

 dered them luminous, the proper motion having been lost by 

 conversion into heat. Mr. Johnstone Stoney, in a paper pub- 

 lished in the Proceedings of the Royal Society for 1868-69, 

 has also dealt with the eventuality of collisions among the stars 

 in a state of proper motion, and remarks (page 53;: — " If what 

 I here venture as a surmise with respect to the proximate cause 

 of stellar heat and the origin of double stars is what really took 

 place, we must conclude the sky to be peopled with countless 

 hosts of dark bodies, so numerous that those which have met 

 with such collisions as to render them now visibly incandes- 

 cent must be in comparison few indeed"*. 



The occasional appearance or blazing forth of " new stars/' 

 so notorious in astronomy, as if due to some sudden convulsion, 

 would be in harmony with the view of collisions. That the stel- 

 lar masses are in translatory motion, moving among each other 

 in various directions and (in general) at such distances apart 

 that gravity [if it exists at all at such distances] is incompe- 

 tent to prevent the paths from being (sensibly) straight lines, 

 is a well-established fact of observation. The application of 

 the principles of the kinetic theory to the case would, there- 

 fore, seem to suggest itself rather in the light of a natural de- 



* The fact of the present writer having arrived at the general conclu- 

 sions enunciated in this article, "before he had seen the papers of Dr. Croll 

 and Mr. Johnstone Stoney, served rather to increase his confidence in the 

 view he had adopted, and which he now ventures to suggest to the readers 

 of the Philosophical Magazine. 



