THE STORY OF NINETEENTH-CENTURY SCIENCE 



enables the astronomer to escape the thraldom of teach- 

 ing music, and to devote his entire time to the more con- 

 genial task of star-gazing. 



Thus relieved from the burden of mundane embarrass- 

 ments, he turns with fresh enthusiasm to the skies, and 

 his discoveries follow one another in bewildering profu- 

 sion. He finds various hitherto unseen moons of our 

 sister planets ; he makes special studies of Saturn, and 

 proves that this planet, with its rings, revolves on its 

 axis ; he scans the spots on the sun, and suggests that 

 they influence the weather of our earth; in short, he 

 extends the entire field of solar astronomy. But very 

 soon this field becomes too small for him, and his most 

 important researches carry him out into the regions of 

 space compared with which the span of our solar system 

 is a mere point. With his perfected telescopes he enters 

 abysmal vistas which no human eye ever penetrated be- 

 fore, which no human eye had hitherto more than vague- 

 ly imagined. He tells us that his forty-foot reflector 

 will bring him light from a distance of " at least eleven 

 and three-fourths millions of millions of millions of 

 miles" light which left its source two million years 

 ago. The smallest stars visible to the unaided eye are 

 those of the sixth magnitude ; this telescope, he thinks, 

 has power to reveal stars of the 1342d magnitude. 



But what does Herschel learn regarding these awful 

 depths of space and the stars that people them ? That 

 is what the world wishes to know. Copernicus, Galileo, 

 Kepler, have given us a solar system, but the stars have 

 been a mystery. What says the great reflector are the 

 stars points of light, as the ancients taught, and as more 

 than one philosopher of the eighteenth century has still 

 contended^ or are they suns, as others hold ? HerscheJ 



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