34 FIRST YEAR COURSE IN GENERAL SCIENCE 



If we could stand upon Venus and observe the earth, we 

 should see that the earth changes its position with relation 

 to the stars, just as the other planets do. 



24. The Revolution of the Planets.' The other planets, 

 like the earth, revolve around the sun, but not in the same 



FIG. 8. --SIMON NEWCOMB: ASTRONOMER. 1835-1909 



With his appointment to the United States Naval Observatory in 1861, 

 his greater life work began. . . . The sun and the moon and the planets yielded 

 their secrets to the call of his mighty intellect, and science has profited to 

 the benefit of humanity in consequence of the life of Simon Newcomb. . . . 

 They buried him in Arlington, where only those who have served their 

 country are permitted to lie. MARCUS BENJAMIN, in Leading American 

 Men of Science. 



period that the earth does. The earth's period of revolution 

 is about 365 days, called one year or twelve months. That 

 of Venus is seven and one-half months, of Mars one year 

 and ten months, of Jupiter about twelve years, of Saturn 

 nearly thirty years. The orbits are all nearly circular, like 



