352 Mr Southerns, Eocperimental Investigation as to Dependence 



Experimental Investigation as to Dependence of the Weight of 

 a Body on its state of Electrification. By L. Southerns, B.Sc. 

 (London), Whitworth Scholar, 1851 Exhibition Scholar. (Com- 

 municated by Professor Sir J. J. Thomson.) 



[Received 9 December 1909.] 



In a previous paper* the writer described an experiment 

 designed to detect any alteration which might occur in the weight 

 of a body when its temperature was changed. The present paper 

 deals with an experiment which seemed naturally to follow the 

 former one, viz. an attempt to detect change of weight due to 

 electrification. This experiment, unlike the other, appears to give 

 a positive result. The object of the experiment is not to actually 

 weigh electricity, but rather to find whether the presence of 

 electricity on a body modifies in any measurable degree the force 

 of gravity acting upon it. While such a modification of gravity 

 seems to provide the simplest way of explaining the results, such 

 explanation is by no means insisted upon. Further reference to 

 this matter will be made in the last section of the paper. 



B 



■^y, 



-y. 



Fig. 1. 



The paper is divided into the following sections : 



(1) General theory and method of experiment. 



(2) Description of apparatus. 



(3) Detailed description of experiments and results. 



(4) Conclusion. 



(1) General theory and method of experiment. 



A general idea of the method employed may be gained from 

 consideration of fig. ] . 



* Proc. Roy. Soc. A, Vol. lxxviii. December 20, 1906. 



