388 



THE BEAUTIES OF NATURE 



Mercury, Venus, Mars, Jupiter, and Saturn — 

 two large ones, Uranus and Neptune, and a 

 group of minor bodies, have since been added. 

 The following two diagrams give the rela- 

 tive orbits of the Planets. 



Mars 



687 days 

 Fig. 51. — Orbits of the inner Planets. 



MEECURT 



It is possible, perhaps probable, that there 

 may be an inner Planet, but, so far as we 



