296 



Mr. Norman Campbell on Delta Rays. 



emergence rays of silver and O480 for the incidence rays of 

 aluminium. The agreement is not good. In the case of Cu-Al, 



Fig. 5. 

 A, Aluminium. 13, Silver. 



^-Q 



the values for emergence aluminium rays and incidence 

 copper rays were 0*362 and 0*445 respectively ; these are to 

 be compared with 0*353 and 0*452. The agreement is much 

 better. However, in neither case can the difference between 

 the emergent and incident radiations found from the maxi- 

 mum values be reconciled by that found by comparing the 

 values for V = and V = (magnet). (In figs. 1, 4, 5 

 the point corresponding to V = (magnet) is marked by 

 a X.) 



However, any other method of interpreting the curves 

 which has suggested itself to me would appear artificial, and 

 could lead to no convincing results. If, notwithstanding the 

 discrepancies, the figures giving the qualities of the various rays 

 are calculated as in Tables I., III., IV., V., the results given in 

 Table VI. are obtained. In the case of the copper-aluminium 



