Heaviside's communication cable designs
K.D. Mayne · Electronics and Power · 1977
Oliver Heaviside produced only one patent, which involved two methods of reducing inductive interference between commmunication cables. The first, a concentric form of cable, was anticipated by other workers; but the second, a balanced configuration of conductors subsequently known as ‘quad’, we must conclude, in the absence of any prior disclosure, to have Heaviside as its original inventor