150 
HAROLD’S DISCUSSIONS. 
Are these nebulae illustrations of the growth of 
solar systems ? They certainly suggest this thought. 
If so, worlds are still forming. Indeed, these nebulae 
are so far away from us that their nebulous light may 
long ago have been changed to pure sunlight. So 
immense are the distances 
that the swift messenger 
light could bring us only 
very tardy news. Yes, the 
news would not reach us 
until thousands of years 
after the transformation 
had occurred. 
There is one nebula in 
the Scorpion that has in 
the last century apparently 
changed into a star and 
then again become nebulous. Others have grown 
luminous at different periods and have again become 
invisible. Such are called variable nebulae. Still 
others are double, and Avill probably in time become 
double stars. 
^lebulae are of different shapes and extent. The 
Cloud of Magellan is a nebulous field in the southern 
hemisphere containing 291 nebulae, 46 clusters, and 
582 stars. Other large nebulous tracts are found in 
different parts of the universe. Our minds grow 
weary thinking of the immensities of space which 
contain all these great and wonderful starry hosts. 
Fig. 74.—Ilerculis again, as it 
appeared in 1883. 
