486 Dr. S. Brodetsky and Dr. B. Hodgson on the 



plotted in fig. 4, A and B respectively. It seems that the 

 first hypothesis, giving the curve A in fig. 4, is the more 

 satisfactory one. A good test would be to perform a series 

 of experiments between the same limits of #, but with 



Fig. 4. 



r/ 3 



different current strengths. The time occupied by the 

 absorption should be proportional to the one and a half 

 power of the current strength. Such experiments would 

 perhaps be rather long and laborious. 



Attempts to obtain a relation between the cathode-fall 

 and the rate of absorption from the data supplied by the 

 results of our experiments, met with only partial success. 

 The mathematical investigation suggests the relation to be 

 one of proportionality, but there is no doubt that the cathode- 

 fall as recorded was subject to considerable experimental 

 error due to lag, especially for small and for very large 

 values of V. 



Fig. 5. 



.100 I20_ 



HYDROGEN 



20Q-MINU7ES- 



In the case of hydrogen, quite a different type of curve 

 was obtained, fig. 5. The absorption was at first rapid, and 



