to the figures given in the preceding Tables. Though the number of cases was few, 

 there seems little doubt that the figures disclose a real tendency, the maxima being 

 roughly at 18 and 23 hours, with a minimum at 21 hours, which is much less definitely 

 indicated. 



For reasons which seemed adequate at the time, the opinion was formed while in 

 the Antarctic that aurora3 showing colour and movement were the most intense, and 

 this is substantiated by the results of the analysis of these classes in respect of the 

 corresponding " magnetic " character numbers. 



Diurnal Frequency and Brightness of Aurora. 



For this analysis, the aurorse have been divided into two classes only (where no 

 mention of brightness of aurora was made in the log, the observations have been 

 neglected) one class comprising bright, moderately bright and fairly bright aurorce, the 

 other class faint and very faint aurora?, all the observations of 1911 being included. 

 A third class is also formed of all observations at certain even hours where the aurora 

 log records :i Clear, no aurora." The figures which are given in Table 8 are of 

 considerable interest. 



TABLE 8. Diurnal Frequency and Brightness of Aurora, Cape Evans, 1911. 



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