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SCENERY OF THE HEAVENS. 



Phases of Saturn. 



earth in corresponding orbital positions. As the rings maintain the same inclination to 

 the plane of the orbit, it is obvious at a glance that their aspect to a terrestrial spectator j 

 must greatly vary, in the course of revolution. Alternately one side is seen and then 



the other, and oval forms of diiferent ellipticity are presented. It also happens that the 

 earth being in the plane of the rings, or in a direct line between them and the sun, only 

 the edge is turned to us, about a hundred miles thick. They are then invisible, except 

 with the aid of the mightiest telescopic power, when a fine line appears drawn across the 

 disk of the planet, projecting on each side. This occurs twice in each revolution, or 

 once in every fifteen years. These are the phases of Saturn, exhibited in the side views, 

 phenomena which astonished Galileo, and which Huygens was the first to explain. At 

 present the northern side of the rings is presented to us. The next disappearance 

 will be in 1847, and the southern side will become visible in 1855. The appearance 

 in the centre represents Saturn and his rings as he would be seen if placed perpen- 

 dicularly above us. 



The annular apparatus of Saturn illustrates the resources of the Creator, and in con- j 

 nection with his moons is no doubt intended to give him compensation for a scanty supply 

 of direct solar light. Three of the satellites are nearer to him than our moon to us, and 

 the other four will be conspicuous objects in the heavens of the planet. The nearest 

 satellite probably presents a disk equal in extent to nine or ten times that of our lunar 



