THE HEART OF THE ANTARCTIC 



ripples of luminescence traversing the curtain at a very- 

 rapid rate. The curtains, as a whole, slowly drift in a 

 determined direction, generally towards the magnetic pole. 

 The displays, however, were very seldom observed in that 

 part of the heavens situated towards the magnetic pole; 

 they usually appeared in the north, through east to south. 

 The arches sometimes travelled towards us from the south- 

 east. Observations of electric potential showed nothing 

 remarkable during displays of the aurora. 



I am informed by the Chief of the Telegraph Depart- 

 ment of South Australia that during September 12, 1908, 

 the telegraph lines, both north and south and east and 

 west across Australia, were much affected by earth cur- 

 rents. At the same time we experienced considerable 

 auroral displays. Since then, on May 14 and 15, 1909, 

 the same authority reports further disturbed earth cur- 

 rents, and it is interesting to note that brilliant auroral 

 displays were observed in the Southern Indian Ocean by 

 a passing steamer. 



NOTES ON THE AUUORA AUSTRALIS 



By JAMES MURRAY 



The different forms exhibited by the aurora could be 

 much better understood from a few pictures than from 

 much description. To depict the delicate and evanescent 

 beams of auroral light by harsh black lines is very un- 

 satisfactory, but as some illustration is desirable, these 

 sketches attempt to give the general forms. Marston's 

 coloured picture gives a good idea of a curtain aurora. 



Curtain Aurora. — At Cape Royds this was by far 

 the commonest type of aurora. It consists of broad 

 ribbon-like bands made up of transverse parallel fibres. It 

 hangs in folds like those assumed by heavy drapery, and 

 looks very like the fringe of separate threads bordering 



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