cir. HI. SfGJVS OF THE ZODIAC. 19 



9. Sagittarius, the Archer; 10. Capricornus, the Goat ; n. 

 Aquarius, the Water-bearer ; 12. Pisces t the Fishes. 



It was by no means an easy thing to trace the sun's path 

 among the stars, because the sun and the stars are never in 

 sight at the same time, so astronomers were obliged to notice 

 the constellations as they appeared close to the sun after 

 he sank at night or before he rose in the morning. These, 

 they found, varied a little each night, till when a whole 

 year had passed away, each of the twelve signs had been 

 in turn close to the sun, and the round began again. Thus 

 they learned that the sun passed over each of the twelve 

 signs in the course of the year ; and they thought from this 

 that the sun travelled round the sky while the earth stood 

 still in the middle. We know now that it is the sun which 

 stands still in the middle while the earth moves round, and 

 it is worth while to make an experiment to see how the 

 Greeks were deceived. 



Put twelve chairs round in a circle to represent the 

 signs of the Zodiac, and put yourself in the middle for a 

 person standing on the earth. Then swing a ball round you 

 just on a level with the chairs. You will see that the ball 

 passes between you and each chair as it makes a circle round 

 you. The Greeks believed that the sun moved round in 

 this way between us and the stars. But now to represent 

 what really takes place, change places with the ball. Hang 

 the ball (the sun) up in the middle just on a level with the 

 chairs, and walk round it. Keep your eye fixed on the ball, 

 and you will see it will pass between you and each chair, 

 just as it did before. The effect is the same, though it is 

 you who are moving this time and not the ball. Thus the 

 Greeks made the same mistake which a child does in a rail- 

 way train when he thinks the houses and trees are flying 

 past, while it is really he himself who is moving. 

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