132 ANSWERS TO PRACTICAL QUESTIONS 



seed-time and harvest, shall occur at the same time of the year 

 through several successive generations ; but it is not of the 

 slightest importance that they should occur now at the same 

 time that they did 5,000 years ago. Read Newcomb's As- 

 tronomy, p. 50. 



86. What religious festival is fixed each year by the 

 motion of the moon ? 



Easter occurs on the Sunday after the first full moon fol- 

 lowing the spring equinox. Read article on Easter, in Apple- 

 tons' Cyclopedia. 



87. Wliy can we, at different times, see both poles of 

 the planet Mars ? 



Because the axis of the planet is so much inclined to the 

 plane of the ecliptic. 



88. Wliat famous astronomical discovery was made 

 on the first day of this century ? 



(See Astronomy, p. 155.) 



89. Do the stars rise and set at the poles ? 



(See Astronomy, p. 102.) 



"At one of the poles of the earth, the axis of the earth's 

 rotation would be vertical, and pass through the zenith, and 

 consequently all the celestial objects would appear to travel in 

 horizontal circles, parallel to the horizon, traversing these hori- 

 zontal circles once in 23 hours 56 minutes 4 seconds." 



90. Name and locate the stars of the first magnitude 

 which are seen in our sky. 



The twenty brightest stars in the heavens, or first magni- 

 tude stars, are as follows: they are given in the order of 

 brightness. LOCKYER. 



Sirius, in the constellation Canis Major. 



Canopus, " Argo. 



Alpha, " Centaur. 



Arcturus, " Bootes. 



Rigel, " Orion. 



Capella, " Auriga. 



