Comments, with reply, on `Closed-form solution for underground impedance calculations´

D.J. Tylavsky et al. (see ibid., vol.74, no.9, p.1290-1292, 1986) formulate the boundary value problem of an electric line source eccentrically located in a cylindrical cavity. Their solution is consistent with the full-wave solution for a similar problem arising in electrical geophysics. The commenter claims that, in reducing their solution to a simpler form, the authors make some physical approximations which are questionable. In replying, Tylavsky et al. agree with Wait´s comments that the application of a planar image model to the case of a conductor eccentrically located in a cylindrical dielectric is indeed a nontrivial problem