CONSTELLATIONS AND PLANETS. 



181 



away from the observer the part of the map towards him has 

 its east to the left and its west to the right. The' reason may 

 appear if the map is looked at while held overhead in such a 

 position that Polaris is in a line from the eye to the North 

 Star. Observe then that the name-numbers of the meridians 

 decrease towards the left, the west, and increase towards the 

 right, the east. 



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About the 21st March, the Sun is on line which is therefore 

 overhead at mid-day ; line 12 is overhead at midnight. About the 

 21st of April, line 14 is overhead at midnight. About the 21st of May, 

 line 16 is overhead at midnight. And thus throughout the year, every 

 30 days the Sun and the midnight zenith move across two meridional 

 spaces towards the east. 



Latitude in the sky, called declination, is counted from the 

 equator north and south. The parallel overhead in the sky 



