McClklLanh and iNToLAN — The Electric Charge on Rain. 83 



Description of Apparatus and Method of Experiment. 



The general disposition of the apparatus may be gathered from the 

 diagram. The rain is caught in a shallow, conical vessel, A B, 81"5 cms. in 

 diameter. This is mounted inside a cubical wooden box, measuring about 

 108 cms. each way, and fitted with a zinc top G D, sloped so as to throw off' 



To ElecTromeTer 



To Bell 



Fig. 1. 



the rain which falls upon it. In this zinc top is a circular opening EF, 79 cms. 

 in diameter, through which the rain falls into the receiving vessel. The edge 

 of the zinc is turned up so as to form a rim about -5 cm. high around the 

 opening. The zinc top is surmounted by a strong zinc cylinder G E, U 1 cms. 



[11*] 



