Experiments on Positive Rays. 



253 



the positive, and shows negatively electrified hydrogen atoms 

 and molecules and oxygen atoms. Thus, in addition to the 

 cathode rays and positively electrified retrograde rays, we 

 have streaming from the cathode negatively electrified atoms 

 and molecules ; the photograph shows that the maximum 

 velocity of the negative atom is about the same as that of 

 the corresponding positive one. This, I think, confirms the 

 view I expressed in a former paper that these positive retro- 

 grade rays are atoms or molecules which get negatively 



Fig. 27. 





























A 













y. 

















1 









A ft 





i 



i 





A 





M 



j 



1 



u 





Carbon Dioxide 520 Volts 



electrified near the cathode, are then repelled from it by 

 the electric field, and subsequently, by collision, lose a nega- 

 tive charge and acquire a positive one. The photographs 

 show, since the negative side is stronger than the positive, 

 that in this case the majority of the charged atoms had 

 retained their negative charge. 



I wish to record my indebtedness to Mr. F. W. Aston, B.A., 

 whose skill in designing and making the numerous pieces of 

 apparatus required in these investigations has been of the 

 greatest assistance, and also to Mr. E. Everett. 



