REQUIRED TO PRODUCE DISCHARGE THROUGH VARIOUS OASES. 



.'{'.I I 



s| ti-oscM|.ir;i]lv. N-i tr.-u'.- .it' iiitn-irrn knuk -.uM } M-.-II. Tin- i.-d liviln^'n linr 



was visible, as it always is in a vacuum tube. This sample of gas gave the following 

 readings when first put into the apparatus : 



1. 



Minimum 326. 



The gas was left in the apparatus untouched. Next day the readings obtained 



were : 



2. 



Minimum 288. 



The gas was again left untouched till next morning: 



Minimum 274. 



