This is in contrast to the usual use of a pair of wires providing a complete circuit, or an electrical cable likewise containing (at least) two conductors for that purpose.
The latter effect was correctly understood by Alessandro Volta as an electric current inadvertently produced by what would become known as a voltaic cell (battery).
relied on the principle of a complete circuit, generally involving a pair of wires, but sometimes using the ground as the second conductor (as with commercial telegraphy).
[5]The final reference to "burning out" a machine was to emphasize the ability of such a system to transmit a large power given a proper impedance match, as can be obtained through electrical resonance.
At much higher frequencies, however, it is possible for the return circuit (which would normally be connected through a second wire) to utilize the self- and parasitic capacitance of a large conductive object, perhaps the housing of the load itself.
As early as 1899, Arnold Sommerfeld published a paper[7] predicting the use of a single cylindrical conductor (wire) to propagate radio frequency energy as a surface wave.
Sommerfeld's "wire wave" was of theoretical interest as a propagating mode, but this was decades before technology existed for the generation of sufficiently high radio frequencies for any such experimentation, let alone practical applications.
Of particular practical interest, though, was the prediction of a substantially lower signal attenuation compared to using the same wire as the center conductor of a coaxial cable.
For these reasons, and at frequencies available prior to about 1950, the practical disadvantages of such transmission completely outweighed the reduced loss due to the wire's finite conductivity.
With technological development at terahertz frequencies, where metallic losses are yet greater, the use of transmission using surface waves and Goubau lines appears promising.
[11] From 2003 through 2008 patents were filed for a system using Sommerfeld's original bare (uncoated) wire, but employing a launcher similar to that developed by Goubau.