who is not present to read it, deals with the inethods devised to combine the extreme simplicity of the single-phase alternating current system with the efficiency of generation and distribution of the polyphase system, by the use of three-phase generators operating single-phase lighting combined with three-phase power, either by having a four-wire primary distribution witlh singlephase secondary circuits as outlined by Mr. Ferguson, or by operating a three-wire single-phase secondary,

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... a fourth wire for motor supply. Mr. Emmet's paper also disc usses the four-wire balanced three-phase secondary system of distribution.