LESSON VII. 



ON MARS, 



In larger circuit rolls the orb ot" Mars, 

 Guiltless of stern debate, and wasteful wars, 

 As some have erring taught: he journeys on, 

 ImpelPd and nourish'd by the attractive sun ; 

 Like us, his seasons and his day he owes 

 To the vast bounty which from Phoebus flows . 



Bnowx. 



1 HE next planet which falls under our consi- 

 deration, is called by the same name as Mars, the 

 heathen god of war ; and very probably, because 

 he appears with a ruddy fiery countenance : among 

 astronomers he is characterised by this mark <?, 

 which seems to be a rude sketch of a man holding 

 a spear protended. Mars is the first of the four 

 superior planet.s, his orbit being immediately 

 above that of the earth : his mean distance from 

 the sun is about 152 of those parts, of which the 

 mean distance of the earth from that luminary is 

 100: hence his real distance is about 144 millions 

 of miles. He performs his revolution round his 

 orbit in about 687 of our days, or 66/| of his own 

 days, which is the length of his year. The light 

 and heat at this planet (calculating after the man- 

 ner described in the fourth Le'sson) are in propor- 

 c 4 tloa 



