﻿50 



Mr. Norman Campbell on Delta Rays. 



of the cnrve was quite unaltered by the presence of the 

 absorbing layer. 



Fig. 2. 



+3 



+1 



r 1 



-2 



-40 



















3 



'/V 















A 



yf 



















f 



















/ 



1 

 1 

 3 



AC 

 Co. 



an 



















A 



%. 







_- --." 





3. —- 























±_ - 

















-6 -4 



VO/LTS 



+4 



+ 6 



+ 8 



+40 



4. A mere glance at the curves in fig. 2 will show at once 

 that the simple theory given at the beginning of the previous 

 paper is quite inadequate to explain the results obtained 

 when one of the electrodes is covered with soot. And, since 

 it is only on the basis of that theory that any deductions as 

 to the speed of the rays can be made from an examination of 

 these measurements, all conclusions which have been sug- 

 gested as to the speed, and many conclusions on other points 

 also, are rendered dubitable. 



For, according to this theory, the upper ( + ) portion of 

 the curve should represent the properties of the rays emitted 

 by the upper electrode (B), while the lower ( — ) part should 

 represent the properties of the rays emitted by the lower 

 electrode (A). But in these experiments the material coveiv 

 ing A, soot, was the same in all cases, while the material 

 covering B varied. It would be expected then that the 

 lower part of the curve should be the same in all cases, 



