Abstract: Woven glass cloth and method of its manufacture suitable for use as a resin-impregnated substrate for printed circuits in which the major dimension or transverse axis of the elliptical warp yarns exceeds a predetermined fraction of that dimension of the fill yarns of the woven cloth. Multi-filament warp yarns are typically subjected to tensile stress during weaving and firing such that the yarn compaction prevents the thorough impregnation by a resin. The result is that voids are maintained along the innermost filaments of the yarn. These voids, when filled with materials other than resin, such as plating solution, ultimately produce circuit failures.