An image torso may be viewed as a one-to-one transform of a physical volume conductor to a geometric form which defines both the axis and sensitivity of any electrocardiographic connection. In this report, the image surfaces of laminar, spherical, rectangular and humanoid physical torsos are explored theoretically and experimentally. All proved to be rounded or spherical in form despite the marked differences in the configuration of the physical conductor. Moderate degrees of dipole eccentricity induced only small departures from this basic circular pattern. Introduction of phase inhomogeneity, however, resulted in more striking deviations from roundness. © 1977.