112 



The results ouly of the readings will be given iu the succeeding lists. 

 The tubes were now enclosed in pasteboard boxes to prevent effects 

 due to light and heat. Each box had a hole just large enough for the 

 insertion of the radium. 



It Avas observed that with a given adjustment the drift of the needle 

 was often tolerably constant, and, for a considerable period in the same 

 direction, yutticient additional resistance was now introduced at K, to 

 cause the needle to drift in the opposite direction so that the intluence 

 of the radium would be exerted against the drift. 



A solution of AgNO- was next used as the electrolyte. The Ag and 

 Cu made a battery to such a degree that no consistent results could be 

 obtained. A considerable amount of Ag was deposited on the Cu elec- 

 trodes. Evidently a very dilute solution would be more likely to give 

 results. The most satisfactory solution used was made liy diluting 3 cc. 

 of the Cu SO4 solution used at tirst to 100 cc. 



In Table Y the radium Avas placed alternately upon X and S and 

 readings taken everv two minutes. 



