518 



BELL SYSTEM TECHNICAL JOURNAL 



constant velocity is equal to that which a free ion would have under 

 the same voltage gradient if it were moving in a medium subjecting it 

 to the same frictional resistance as is experienced by the bound ion of 

 our model. 



(7) In ordinary electrolytic conduction the conductivity is usually 

 represented as the product of three factors: the number of ions per 

 unit volume; their valence or charge per ion; and the average mobility 

 of each ion, i.e., the average distance which an ion drifts per second in 



100 



20 30 40 50 60 70 80 



FREQUENCY IN KILOCYCLES PER SECOND 



Fig. 4- — Dependence of e', e", 7' and €"/(«' — «co) upon frequency for ice at — 2.6° C. 



the direction of the applied field. The above statement refers to one 

 species of ion; when two or more species are present in the solution, 

 the total current or conductivity is the sum of the currents or conduc- 

 tivities contributed by each type. The infinite-frequency conductivity 

 7oo may also be represented as the product of three factors similar in 

 physical meaning to those just mentioned as applying to conduction 

 by ions in solution. Thus reference to Table I, Item 2, will show that 



