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POPULAR SCIENCE MONTHLY. 



only with the aid of photography) is lost, because most of them are 

 too faint to be seen with ordinary telescopes, or, if seen, to make 

 any notable impression upon the eye. The two largest — Titan and 

 Japetus — are easily found, and Titan is conspicuous, but they give 

 none of that sense of companionship and obedience to a central 

 authority which strikes even the careless observer of Jupiter's sys- 

 tem. This is owing partly to their more deliberate movements 



Polar View of Saturn's System. The orbits of the five nearest satelHtes are shown. 

 The dotted line outside the rings sliows Roche's hmit. 



and partly to the inclination of the plane of their orbits, which 

 seldom lies edgewise toward the earth. 



But the charm of the peerless rings is abiding, and the interest 

 of the spectator is heightened by recalling what science has re- 

 cently established as to their composition. It is marvelous to think, 

 while looking upon their broad, level surfaces — as smooth, appar- 

 ently, as polished steel, though thirty thousand miles across — that 

 they are in reality vast circling currents of meteoritic particles or 



