Experiments on Positive Rays. 249 



positive charge? It seems to me that we can get valuable 

 information on this point by the study of the positive rays, 

 now that, by the Faraday cylinder method, we can measure 

 the number of positive rays of any kind taking part in the 

 discharge. Let us take as an example the case of CO. 

 If the carbon atom in this compound were positively 

 charged, the oxygen atom negatively, then if a molecule 

 of CO were split into atoms by the impact of a positive 

 particle, the carbon atom would be positively electrified, 

 the oxygen one negatively. The negatively electrified 

 oxygen atom would move away from the cathode, and 

 though it might after reaching the negative glow some- 

 times acquire a positive charge and be attracted to the 

 cathode and become a positive ray, we should expect that 

 the number doing so would be small compared with the 

 number of carbon atoms which start with a positive charge. 

 Thus, if the atoms in CO are charged we should expect to 

 find in the positive rays produced when the discharge passes 

 through CO, a much greater number of carbon atoms than 

 of oxygen ones. I have investigated by the Faraday 

 cylinder method the discharge through CO, the result is 

 represented in fig. 23. It will be seen that the number of 

 positively charged carbon atoms only exceeds that of the 

 positively charged oxygen ones in the ratio of 11 to 7 ; and 

 this number underestimates the number of oxygen atoms 

 which came through the cathode, for some of these after 

 getting through the cathode acquired a negative charge. 

 Measurements by the Faraday cylinder showed that about 2/7 

 did so, while the number of carbon atoms acquiring a negative 

 charge was insignificant in comparison. Taking the nega- 

 tive oxygen atoms into account as well as the positive, we 

 find the proportion between the carbon atoms and the 

 oxygen ones as 11 to 9 ; the numbers are so nearly equal as 

 to preclude the atoms carrying opposite electrical charges 

 when in the molecule. 



Further evidence against the existence of these charges 

 on the atoms is afforded by the consideration of the number 

 of atoms in the positive rays which carry multiple charges. 

 If the atoms in CH 4 or C0 2 , for example, were charged, we 

 should expect to find a considerable number of carbon atoms 

 with four charges, whereas as a matter of fact no such 

 atoms have been observed. 



The view of the forces between the atoms in the molecule 

 of a gas which is most in accordance with the behaviour of 

 the positive rays, is that these forces are due to the atoms 

 behaving somewhat after the manner of electrical doublets ; 



