LITTLE for comets when this star came within his vision. 

 JOURNEYS Others had seen it too, but had classified it as "a va- 

 grant fixed star." It was the -work of Herschel to dis- 

 cover that it was not a fixed star, but had a defined 

 and distinct orbit that could be calculated. To look up 

 at the heavens and pick out a star that could only be 

 seen with a telescope pick it out of millions and as- 

 certain its movement seems like finding the proverbial 

 needle in a haystack. 



The present method of finding asteroids and comets 

 by means of photography is simple and easy. The 

 plate is exposed in a frame that moves by clock-work 

 with the earth, so as to keep the same field of stars 

 steady on the glass. After two, three or four hours ex- 

 posure the photograph will show the fixed stars, but 

 the planets, asteroids and comets will reveal them- 

 selves as a white streak of light, showing plainly where 

 the sitters moved. 



Herschel had to watch each particular star in person, 

 whereas the photographic lens will watch a thousand. 

 Q How close and persistent an observer a man must 

 be, who, watching one star at a time, discovers the one 

 in a million that moves, is apparent. Chance, surely, 

 must also come to his aid and rescue if he succeeds. 

 Q Herschel found his moving star, and at first mistook 

 it for a comet. Later he and Caroline were agreed that 

 it -was indeed their long-looked-for planet. There are 

 no proprietary rights in newly discovered worlds 

 the reward is in the honor of the discovery, just as the 

 best recompense for a good deed lies in having done it. 

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