3 ic NINETEENTH CENTURY. FT. in. 



systems which we come across are the only ones existing. 

 On the contrary, we have every reason to think that they 

 are only a few out of thousands of meteor-systems which we 

 never meet, and which probably grow more numerous the 

 nearer they approach the sun. 



And so we arrive at the wonderful thought that the 

 whole of our solar system is swarming with meteors col- 

 lected into more or less denned rings and rushing along with 

 immense speed in their motion round the sun. What their 

 use is we do not know. Some astronomers have imagined 

 that the heat of the sun is kept up by these meteoric stones 

 falling in countless myriads on his face, but this is disputed 

 by others ; and for the present it is enough if we can picture 

 to ourselves these rings of meteors whirling round and round 

 in space, and flashing into light as they rush through our 

 atmosphere whenever we happen to cross their path. 



Use of Improved Telescopes in Discovery of New 

 Heavenly Bodies. In truth, astronomy has during the 

 last twenty years advanced so rapidly along different lines 

 that we cannot follow them in a general history. The 

 improvement in telescopes alone has made many observa- 

 tions possible which before were not so. Instead of rough 

 instruments, constructed under great difficulties like the 

 telescopes of Galileo and Sir W. Herschel, magnificent 

 refracting telescopes, with large achromatic lenses, are 

 now found in all good Observatories. The finest re- 

 fracting telescope in the' world is that of the United Stales 

 Naval Observatory, Washington, with an aperture of twenty- 

 six inches, while one still larger is being constructed for the 

 Vienna Observatory. The finest reflecting telescopes are 

 Lord Rosse's, of a six-foot aperture, and that of the Mel- 

 bourne Observatory, Australia, of a four-foot aperture, and 

 the Lick telescope in California. 



