It is noted that the admittance of a dipole in the King-Middleton theory is obtained by solving Hallen's integral for the current in the form of a series of continuous functions obtained by the iteration of a suitable Nth-order approximation. King et al. (1966) found that whereas the conductance converges to a stable value at the second-order approximation, the susceptance diverges with increasing order. The empirically determined susceptance values of the knife-edge capacitance given by King et al. are found to be reliable for thin dipoles but not for thicker ones. The reason for this imperfection is ascertained, and a table giving the corrected values is presented.