X THE STARRY HEAVENS 427 



In some cases, moreover, nebulae seem to 

 be gradually condensing into groups of stars, 

 and in many cases it is difficult to say whetlier , 

 we should consider a given group as a cluster 

 of stars surrounded by nebulous matter or a 

 gaseous nebula condensed here and there into 

 stars. 



" Besides the single Sun," says Proctor, 

 "the universe contains groups and systems 

 and streams of primary suns ; there are 

 galaxies of minor orbs ; there are clustering 

 stellar aggregations showing every variety of 

 richness, of figure, and of distribution ; there 

 are all the various forms of star cloudlets, 

 resolvable and irresolvable, circular, elliptical, 

 and spiral ; and lastly, there are irregular 

 masses of luminous gas clinging in fantastic 

 convolutions around stars and star systems. 

 Nor is it unsafe to assert that other forms 

 and varieties of structure will yet be dis- 

 covered, or that hundreds more exist which 

 we may never hope to recognise." 



Nor is it only as regaxds the magnitude 

 and distances of the heavenly bodies that we 

 are lost in amazement and admiration. The 



