20 and 22 hours. The results are tabulated in Table 11. Bernacchi, however, states* 

 that at Cape Adare the maximum display in 1899 was at 9 p.m. 



TABLE 11. Distribution in Time of Aurora, 70 Altitude and over, Cape Adare, 1911. 



, (b) Aurorce in the Sectors South to West. 



A similar analysis of the occurrence of auroree in the minimum sectors is shown 

 in Table 12, only the most definite occurrences being considered, i.e. occurrences at 

 altitudes of 80 or less. Again, two maxima and one minimum are seen at approxi- 

 mately the same times as for aurorse in the zenith. The maxima and minimum are, 

 however, not very well marked, and there seems a tendency for the morning maximum 

 to occur later in the day. 



TABLE 12. Distribution in Time of Auroree in S.-W. Quadrant, Cape Adare, 1911. 



(c) Coloured Aurorce. 



Mention was made of colour (chiefly green), in describing the aurora, on 210 

 occasions during the months March to September, the number of occasions on which 

 colour was mentioned at the different hours being given in Table 13. In this Table, 



TABLE 13. Distribution in Time of Coloured Aurorse, Cape Adare, 1911. 



the last line gives the corresponding figures for the three darkest months only, 

 viz., May, June, and July. Again, a maximum is shown in the morning at about 

 6 hours, with another maximum (of greater amplitude in this case) at 20 hours. It 

 will be observed, however, that the usual minimum between 20 and 22 hours is not 

 shown in the case of the longer period, though fairly well marked for the three darkest 

 months only. This difference between the two periods seems to be due to the fact 

 that, both in August and September, there were more occurrences of aurorse between 

 20 and 22 hours than between 18 and 20 hours, no doubt due in part to the fact that 



* " National Antarctic Expedition, 1901-1904," ' Physical Observations,' p. 100. 



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