THK NUMBER OF THE STAKS. 



117 



view of astronomy is really a descriptive one ; astronomy is a 

 <lescriptive science, and he supposed that that was very largely true 

 of science in general. It gives no precise answer to the questions, 

 " How does this come about ? " or " Why does it come ? " The answers 

 that it gives are mainly to the question, " What does it resemble ? " 



In thinking about the Number of the Stars, although that subject is 

 so interesting in itself, it is almost as interesting to recollect how 

 this knowledge has be'en acquired. It has been acquired by thought, 

 l)ut the thought itself has been supplemented in very curious fashions. 

 It was certainly remarkable that had it not been that people had 

 learnt to shape pieces of glass so as to make spectacles, and had then 

 gradually developed this art of figuring glass until they formed the 

 lenses of which Dr. Chapman has spoken, had it not been for the 

 development of that art, our knowledge of the stars must have 

 remained extremely limited. The telescope was a beautiful and 

 wonderful instrument, simply on the ground that it magnified our 

 faculties so mucii. The same remark applied to the microscope, 

 and those electrical instruments by which whole series of phenomena 

 had been discovered of which otherwise we should have known 

 nothing at all. When they considered the heavens and the number 

 and brightness of the stars themselves, he thought they would all 

 feel still more impressively that as religious man had always looked 

 with wonder and reverence on the skies, so that the more we learnt 

 concerning them, the more that wonder and reverence was increased. 



A Member enquired how it was possible to find out the rate of 

 movement of the stars bv means of the spectroscope. Also what 

 was, approximately, the centre of the stellar universe. 



Capt. McNeile asked whether there were not many dark stars, 

 and Mr. M. L. Rouse asked how long it was since it was thought 

 that the stars were suns. 



The Lecturer in reply, said : The first question was as to our 

 knowledge of the motions and of the constitution of the stars 

 revealed to us by the spectroscope. I suppose that we all know, or 

 have been told, that when a railway train is approaching us, and 

 steam is being let off, so that its whistle is blowing, the note appears 

 shriller than when it is going away from us. The sharp note as the 

 train approaches is due to sound waves in the air, which travel with 

 a certain definite speed. If the source of these waves is approaching 

 us, we receive the waves more quickly than if the source were at 



