The Six-Inch Refracting Telescope. 



its walls are suspended many beautiful photographs, Radium star- 

 maps, mechanical star and planet finders and interesting apparatus, 

 chief of which is one which shows, not only the causes of the phases 

 of the Moon, but produces them when set in motion. 



There is also another set of planet models in color, to scale, but 

 made flat so as to occupy less room. The visitor cannot fail to be 

 impressed when he realizes that the little disk, scarcely an inch in 

 diameter, indicates the size of our Earth as compared with the great 

 Dome overhead which represents our Sun. 



The six-inch euqatorial objective is equipped with the Hour circle 



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