star groups separated from his own by great void intervals.

* * * * *

The revelations of the telescope show us certain features in the
constitution and movements of the fixed stars which now demand our
attention. In the first place, it is plain that not all of these
bodies are in the same physical condition. Though the greater part of
these distant luminous masses are evidently in the state of
aggregation displayed by our own sun, many of them retain more or less
of that vaporous, it may be dustlike, character which we suppose to
have been the ancient state of all the matter in the universe. Some of
these masses appear as faint, almost indistinguishable clouds, which
even to the greatest telescope and the best-trained vision show no
distinct features of structure. In other cases the nebulous
appearance is hardly more than a mist about a tolerably distinct
central star. Yet again, and most beautifully in the great nebula of
the constellation of Orion, the cloudy mass, though hardly visible to
the naked eye, shows a division into many separate parts, the whole
appearing as if in process of concentration about many distinct
centres.

The nebulas are reasonably believed by many astronomers to be examples
of the ancient condition of the physical universe, masses of matter
which for some reason as yet unknown have not progressed in their
consolidation to the point where they have taken on the
characteristics of suns and their attendant planets.

Many of the fixed stars, the incomplete list of which now amounts to
several hundred, are curiously variable in the amount of light which