Discussion on “classification of alternating-current motors” (Fynn), and “the classification of electromagnetic machinery” (Creedy), Deer Park, Md., June 30, 1915. (see proceedings for May and July, 1915)

A. S. McAllister: Mr. Creedy mentions several types of motors according to his classification, (A), (B), (C) and (D). Under (A) he includes balanced polyphase machines and under (B) he includes elliptical field machines, such as single-phase and unbalanced polyphase apparatus. He states that the elliptical field machines must necessarily have a commutator. Therefore, in the elliptical field machines he does not include the single-phase induction motor without a commutator.