1904 - 5 .] On Prof. Seeligers Theory of Temporary Stars. 551 
point of view, however crude it may appear in its present form,* 
the difficulties of Mr Moulton’s first and third category are at once 
removed, and those of the second certainly reduced. We under- 
stand better why the distribution of matter in the solar system 
should be so heterogeneous, and why there is not that constancy 
of the moment of momentum which would have to be expected if 
the Laplaceian hypothesis were correct. Besides, we are here for 
the first time confronted with a possible explanation of how 
rotation may have been introduced into the solar system. In the 
problem of cosmic evolution, this question has always proved an 
insurmountable difficulty to those philosophers who attempted to 
trace the natural development of our world from the primordial 
chaos. That matter endowed with gravitational force may have 
contracted from nebulae into spherical bodies, and that these latter 
may have originally been impressed with chance motions through 
space — such conclusions are quite compatible with our conception 
of the chaos where chance has ruled supreme. But how, from this 
anarchy of forces and directions, a system of cosmic bodies could 
have been moulded, in which one particular tendency of motion 
prevails to the exclusion of all others — this question has so far been 
considered as pertaining to the domain of metaphysics rather than 
of natural philosophy. The difficulty seems now to be somewhat 
lessened, inasmuch as it can be shown that the chance approach of 
a star towards a nebular or meteoric agglomeration of matter may 
entail the formation of a rotating ring surrounding the star, and also 
the impression of an equally directed moment of momentum upon 
the body itself. It seems not unlikely, therefore, that in the pheno- 
menon of a new star we notice the initial stage of the fabric of a 
solar system, and that Nature presents here to our eyes — although, 
perhaps, on a less gigantic scale — a sequence of events which had 
taken place in our own system in the remote past. 
Note added on 31 st January 1905. — It has been pointed out to 
me that I do not explain the noteworthy fact that the nebular 
lines have appeared a considerable time after the outburst, and 
were not present during the initial stages, whereas the theory 
demands the existence of nebular matter round the star from the 
* See ray paper, “Some Suggestions on the Nebular Hypothesis.” 
