ASTRONOMY. 24 1 



alludes to its influence. " Being governed as the sea is by the moon," 

 again, 



" It is the very error of the moan, 



She comes nearer to the earth than she is wont, 

 And drives men mad." 



MARS 



Is the first of the superior planets; his orbit is immediately above that 

 of the earth, and revolves round the sun at the nearer distance of one 

 hundred and forty-five millions of miles ; this planet is chiefly remark- 

 able for his dull red light, which is supposed to have occasioned his 

 being considered by the ancients as the God ofbattltL, 



Mars is much smaller than the earth, being only four thousand two 

 hundred and twenty-nine miles in diameter. He makes his revolution 

 round the sun in six hundred and eighty-six of our days twenty-three 

 hours and a half, with the velocity of fifty-five thousand two hundred 

 and eighty-seven miles per hour. He revolves on his own axis in 

 twenty-four hours and forty minutes, at the rate of five hundred and 

 fifty-six miles per hour, at his equator. Mars changes like the moon, but 

 never forms a crescent as the inferior planets do. From his dull light, it 

 is conjectured that he is surrounded by a thick, cloudy atmosphere; his 

 light is much less brilliant than Venus, though he is sometimes, from his 

 position, nearly equal to her in magnitude. The analogy between Mars 

 and the Earth is closer than that of any other planet, except in relation 

 to his atmosphere, which is denser than ours. 



JUPITER. 



This is the largest of all the planets, being eighty-nine thousand one 

 hundred and seventy miles in diameter, about one thousand four hun- 

 dred times larger than the Earth. His distance from the Sun is 

 reckoned to be four hundred and ninety millions of miles, and he moves 

 in his orbit at the rate of twenty-five thousand miles an hour, or about 

 one fourth of the velocity of Mercury ; this he does in eleven years three 

 hundred and fifteen days and fourteen hours; but his astronomical day 

 is not half so long as ours. The diurnal rotation on his own axis is 

 amazing, being at the rate of twenty-six thousand miles per hour! 

 Jupiter, when viewed through a good glass, appears to have a luminous 



R 



