•^ NOTE anJ COMMENT |^<» 



SuxLiGHT IX High Latitudes. — At the north pole the 

 plane of the equator coincides with the horizon plane so that 

 on March 21st, or rather a few days earlier owing to the effect 



of refraction, the sun appears on the horizon and makes a 

 complete circuit of the heavens in twenty four hours with- 

 out setting. This brings to an end the long winter night of 

 six months duration. From this time until the sun crosses 

 the equator going south in September, it remains continually 

 above the horizon for the observer at the north pole and grad- 

 ually makes it way upward until it reaches an altitude of 23^ 

 degrees at the beginning of summer in June. It then begins 

 to gradually wend its way downward once more toward the 

 horizon, disappearing beneath it at the beginning of fall for 

 another six months. At latitudes between the north pole and 

 the polar circle the sun appears above the horizon before the 

 beginning of spring and rises and sets daily until it reaches 

 a distance north of the equator equal to the observer's distance 

 from the pole. It then makes a complete circuit of the heavens 

 without setting, touching the horizon at the north point and 

 tile phenomenon of the midnight sun can be seen. The sun 

 remains continually above the horizon from that day on, at- 

 taining a little higher altitude each day until the beginning of 

 summer. After that its altitude above the horizon begins 

 to decrease. When it has reached the same point as before 

 on its siiutliward iournev it rises and sets dailv once more until 



