The Astronomical Outlook 



course, are well known, and some of those best 

 known are the most mysterious of all. Con- 

 jectures are numerous, but all seem to be more or 

 less unsatisfactory and in conflict with some of 

 the observed data. We can as yet only guess 

 at the forces which produce the peculiar phe- 

 nomena that accompany the approach of a comet 

 to the sun, and develop the magnificent trains 

 of luminous matter which have always excited 

 the wonder, and often the terror, of mankind. 

 Photography has already made great progress 

 in registering these phenomena, and bringing out 

 features invisible to the eye, but apparently of 

 high significance. It will certainly go much far- 

 ther in the. future. And investigations in the 

 physical laboratory will almost certainly here- 

 after render intelligible much of the behaviour 

 that is now so perplexing. The subject is a most 

 fascinating one, and certainly will not be ne- 

 glected. 



And now that the meteors are reckoned as 

 astronomical bodies, they also are receiving 

 careful attention, and our knowledge of their 

 relation to comets and to the universe is rapidly 

 growing. We may well hope that during the 

 coming century this new domain of astronomy, 

 annexed only some thirty years ago, will become 

 a fruitful and important department of the 

 science; and that, even if time should not wholly 

 make good the bold speculations of Sir Norman 

 Lockyer and others, who see in meteoric swarms 

 the very essence and substance, not of comets 

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