ANTARCTIC ADVENTURE AND RESEARCH 



modify the usual pressure conditions. When they in- 

 tensify these normal conditions a furious blizzard re- 

 sults; when they counteract them calms or northerly 

 winds result at Cape Evans. 



Aurora Australis 



Throughout the winter we maintained an aurora 

 watch primarily with a view to determining their re- 

 lation to magnetic or meteorological phenomena. The 

 first observation was made on April 2nd, 191 1, by 

 Captain Scott. He noted that it extended to within 

 10° of the zenith from the south. It was of a reddish 

 hue and took the form of a curtain with two folds. On 

 the 28th of April I was on watch and saw an elaborate 

 display about 9:10 p.m. It affected the whole sky to 

 the east (behind Erebus). At first isolated grayish 

 streamers reached over 8° ; they had a reddish tinge, 

 but were not bright enough to show the ''auroral line" 

 in the spectroscope. The whole brightened until it be- 

 came a continuous band of yellowish light. It con- 

 centrated with a movement to the north, reminding one 

 of a caterpillar's motion as the more vivid mass of 

 light undulated towards Erebus. At one moment it 

 clotted into a globule of light not unlike a meteor, 

 pointing to the crater, with a streamer extending up 

 and slightly to the south. During the maximum the 

 streamers were over 20° from the horizon. Dr. Wil- 

 son saw traces of orange and purple in the borders. 

 The display lasted six minutes. 



Mawson records that at Cape Royds in 1908 they 

 saw auroras from March 26th to October 4th. They 



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