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THE ROYAL SOCIETY OF CANADA 



metric pressures at the times of observation were obtained through 

 the courtesy of Dr. Abbot. 



Pending full publication and a more detailed discussion of the 

 results obtained, a summary of the mean values of /3 and Y together 

 with the corresponding determinations of n and the probable de- 

 viation from the mean is given in the following table. 



Constants of Atmospheric Absorption. 



Mount Whitney, California. Elevation, 4420 metres. Average 

 Barometer, 446-7 mm. 



Bassour, Algeria. Elevation, 1160 metres. Mean Barometer, 

 664-6 mm. 



The marked increase of 7 in the second series at Bassour is due 

 to the presence of volcanic haze from the Mount Katmai eruption, 

 June 6-7, 1912. 



Mount Wilson, California. Elevation, 1780 metres. Mean 

 Barometer, 623-5 mm. 



The mean value of n obtained by combining the results of Tables 

 34, 35, and 36 (324 days, 1909-11) gives n = (2-78 x ± -01 3 )X10 19 . 

 Hence we obtain for Avogadro's Number the value N = (6-23 ± -03) 

 X10 23 and for the charge on the electron e = (4-64 ± -02) X 10" 10 

 e.s. units. 



