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1893 O. Heaviside Electromagn. Theory I. iv. 368 If we abolish the fictitious magnetic conductivity throughout the medium traversed by the waves we should, to have distortionless transmission, also abolish the electric conductivity. This is only to be attained by using wires of no resistance to guide the waves through a non-conducting medium.

1902 Encycl. Brit. XXXIII. 214/2 The use of conductors will now be seen partly. They serve to guide a wave along from place to place without loss, and with a limited amount of energy.

1925 A. H. Morse Radio iii. 66 [He] enunciated the theory that a ‘Heaviside Layer’ was unneccessary, since all radio waves were guided by the earth, which was the real conductor; just as was the wire, in guided-wave telephony or telegraphy.

1936 Bell Syst. Techn. Jrnl. 15 285 It is possible to reduce the size of the guiding structure for a given frequency by the use of a suitable dielectric.

1936 Bell Syst. Techn. Jrnl. 15 312 In the ordinary type of guided-wave systems..the guiding conductors form two sides of a circuit in which equal and opposite currents flow.

1947 W. H. Watson Physical Princ. Wave Guide Transmission p. v A dielectric cylinder may also be used to guide electromagnetic waves of sufficiently high frequency and is usually called a dielectric guide.

1962 D. R. Corson & P. Lorrain Introd. Electromagn. Fields xii. 429 In the process of guiding electromagnetic waves conductors waste part of the wave energy in the form of Joule losses. This is because the guided waves always induce electric currents in the conductors.