64 



Proceedings of the Roijal Irish Academy. 



Taule II. 

 B. — Niijatice Bain. 









Charge per c.c. in Eleclrostatic Units. 









Moulh. 















< -1 



•1 - -2 



•2 - -3 -3 --ii- -0 



■0-1 



1 -2 J2-3 



3-4 



4 - -5 



> 5 



Oct. and Nov.. 



•5 



■i 



2 3 



2.212 



_ 



— 



_ 



_ 



December. 



8 



1 



— — 



_ _ _ 



— 



— 



— 



- 



January, 



34 



- 



- - 



- - 



- 



- 



- 



- : 



- 



Febiuaiy, 



32 



— 





— 



— ■ — 



— 



— 



— 



— 



- 



March, 



9 



— 





— 



2 



4 



1 



1 



— 



6 



May, 



12 



— 





- 1 2 - 



- 



- 



— 



- 



- 



Total, 



100 



5 



2 3 ■ 4 4 



6 



1 



1 







6 



The coiitrast between the charges observed in winter and those observed 

 at other times is, perhaps, best sliown in the case of the negatively charged 

 rain which, as the above table shows, gave practically no charge higher than 

 •1 E. S. unit per c.c. during the months of December, January, and February. 



Di^eretit Types of Bain . 



In the prev'ious paper we drew a distinction between three classes of ram ; 

 (1) " Fine rain," consisting of exceedingly small drops which are always 

 negatively charged ; (2) " Large rain," consisting of drops relatively very 

 much larger ; and (3) " Mixed rain," consisting of a mixture of types (1) and 

 (2). This classification with some extensions still affords a convenient basis 

 for discussing our more extended observations. 

 '■' Large " Bain. 



The " large rain " is higlily charged. The excess of this rain is positively 

 charged, and the average value of the positive charge per c.c. is from 1 to 2 

 electrostatic units. Very high positive charges sometimes occur, values as 

 great as 12 electrostatic units per c.c. having been observed. The negative 

 charges which occvu' with this type of rain are always high also ; their values 

 are about the same as that of the positive charg&s, but they occm- less 

 frequently. Abnormally high negative charges are also observed, as in the 

 case of the positive. The manner in wliich the negative charges on this 

 " large rain " appear was noted in the pre^^ous paper. The usual positive 



