Abstract
The KCl‐bridge which is so frequently used in practice lacks its necessary theoretical foundation. Basing upon the differential equations of “free” diffusion, it is possible to develop a satisfactory theory which leads to reliable values for the diffusion potentials concerned. It is shown by a similar treatment that the assumption made in our previous paper, according to which the problem of free diffusion can be solved in terms of y = x/2 √ t entirely justified.