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cause of the tides. She, by the advantage science has taken of 

 the rapid changes of her position with reference to the stars, 

 guides the mariner across the ocean. In courtly and in rustic 

 life, in palaces and in cottages, the lunar world has been regarded 

 with respect and admiration as an emblem of modest beauty and 

 faithful attendance. And while her varying aspects have indica- 

 ted to barbarous tribes weeks and months, times and seasons, 

 astronomers have studied them with greater attention than any 

 other celestial appearances, owing to her greater proximity, 

 bringing the orb within more convenient range of their 

 telescopes. 



Some of the finest bursts of poetry have been inspired by the 

 placid lovehness of the Queen of Night. 



We find in Pope's translation of Homer the following beauti- 

 ful lines : — 



" As when the moon, refulgent lamp of night. 

 O'er heaven's clear azure spreads her sacred light. 

 When not a breath disturbs the deep serene, 

 And not a cloud o'ercasts the solemn scene, 

 Around her throne the vivid planets roll, 

 And stars unnumbered gild the glowing pole. 

 O'er the dark trees a yellower verdure shed. 

 And tip with silver every mountain's head. 

 Then shine the vales, the rocks in prospect rise, 

 A flood of glory bursts from all the skies, 

 The conscious swains, rejoicing in the sight, 

 Eye the blue vault, and bless the useful light.' 



The Apparent Movements of the Moon. 



It is an easy matter for any one to see for himself that the 

 moon is continually changing. If he watches its movements 

 among the fixed stars for an hour or two he will see that it 

 moves from west to east, that the stars which lie in its path 

 disappear on its east side and reappear on the west side. If the 

 moon's path be traced out among the fixed stars, it will be seen 

 to lie in a plane which makes an angle of 5° 8' 47" with the 

 plane of the ecliptic. Sometimes it is below the ecliptic, at 

 other times it is above the ecliptic circle. The points at which 

 the path of the moon intersect the ecliptic are called its nodes. 

 The ascending node is that point of intersection in which the 

 moon passes from the south to the north side of the ecliptic, 

 and the descending node is that point of intersection in which the 

 moon passes from the north to the south side of the ecliptic. 

 The nodes of the moon are not fixed, but are continually chang- 

 ing, retrograding, moving in the opposite direction to that in 

 which the moon moves. So that in 18 years 224 days they 

 make a complete revolution round the ecliptic. 



