398 



Reports on Special Researches 



In the observations of the potential-gradient, the positions of both fibers of the electro- 

 scope are recorded, and are designated in the form by "left" and "right," respectively. 

 Space is provided for the conversion to volts of each of the readings so obtained. When, 

 however, over the range used, the scale of the electroscope is sufficiently linear as regards 

 potential variations, it is sufficient to deal, as in the example given, with the means of the 

 scale differences, and convert these to potentials. 



Atmospheric-Electric Observations: Ionic Content, Conductivity, and Specific Velodiif 



(Form 101) 

 Station: At sea Lat: 54°35 S Long: 326?8 E 



Date- Jan. 15, 1916 Com'd'r: J. P. A. Obs'r: H. F. J. 



Inst: I. C. 1 and C. A. 3 Watch: 106 



'For an explanation of the formulte see pages 384-389. 



