Following an entropy approach, the electric current can be postulated as a flow of electromagnetic waves that has an electric potential. Such postulate is verified in this article by results of experimental measurement then it is applied to review Tesla's discovery of wireless power transmission. Tesla discovered the wireless transmission of electric power during his operation in an entirely new domain of physics based on abrupt discharging of electrostatic charges. He realized that electrons were not responsible for such discovered phenomena. So, he called the new energy as "Radiant Electricity". He didn't identify that the true nature of electric current was a flow of electromagnetic waves that can be normally radiated through air. So, he proposed the term "Aether gas" to describe the discovered transfer of the electric charges by radiation from his designed tower, though air, to specified receivers. Following an entropy approach, the nature of the discovered radiated energy can be identified as electromagnetic waves that have an electric potential. So, the followed approach succeeds in eliminating the confusing observations of Tesla's measurements in his famous experiment and the confusions found in modern literature that deals with such energy as an "Ambiguous Radiant Energy".