Cathode Rays and certain Chemical Effects. 217 



As the phosphorus was contained in a chamber separated from 

 the actual discharge-tube by a U-tube immersed in liquid 

 air, it is impossible to argue that the observed effects might 

 be due to a direct action o£ the rays on any phosphorus vapour 

 that might have made its way into the actual path of the rays. 

 Clearly the rays so modified the gas through which they passed 

 as to render it chemically active towards the phosphorus. 



As the gas in these experiments was necessarily — with the 

 exception of traces of the rarer gases of the atmosphere — 

 exclusively nitrogen, these results bear interestingly on 

 certain results of R. J. Strutt, who finds that nitrogen, when 

 subjected to an energetic electric discharge, assumes a certain 

 chemical activity which enables it to react with various 

 substances in a manner and according to a mechanism as yet 

 not fully determined *. 



A special study was made of this effect of cathode rays on 

 nitrogen and its relation to the attendant chemical effects 

 between the gas and phosphorus. 



Fio; l 



To PUMF 



/O EARTH 



W& 



R= To G/WG£ 



I FIG. Ua) 



u, u 2 



C 2*C 2 



The apparatus shown in fig. 1 (a and 6) was set up for the 

 purpose of working with definite measurable quantities of 

 gas, homogeneous rays, &c. 



* "An active modification of Nitrogen," Proc. Roy. Soc. March 1911, 

 et seq. 



Phil Mag. S. 6. Vol. 25. No. 146. Feb. 1913. Q 



