THE SIDEREAL UNIVERSE. 735 



temporaneous events ! This is, as has been said, the most 

 authentic proof of the immense antiquity of matter. 



CHAPTER II. 



THE NEBULjE. 



Tlie investigation of the universe is not limited to the 

 stars. By means of large telescopes we discover at the 

 farthest distances in the heavens Avliite patches of dif- 

 ferent shapes, which were long regarded as simple cos- 

 mical, phosphorescent vapoiu's, or as germs of the universe 

 ready to be condensed into new Avorlds. It is to these 

 white gleams that the name of nebiike was given, in order 

 to designate their diffused appearance and the uncertainty 

 of their nature. But by means of newly-invented powerful 

 instruments it has been made out that these luminous 

 clouds, in which it was thought man had discovered 

 globes in the process of formation, are only groups of 

 small telescopic stars, often aggregated in considerable 

 numbers, and assuming the most varied and imexpected 

 figures. 



Some nebulce are nearly globular, others, like those in 

 the constellations of the Virgin and the Greyhounds, are 

 like a spiral whirlwind, and there are some which resemble 

 a ring. The nebula of the Bull shows like a luminous 

 body lengthened out, from wliich project claAv-like ap- 

 pendages formed by long trains of stars. Struck with 

 its appearance, Lord Eosse, when he saw it for the first 

 time through his immense telescope, gave it the name of 



