At the last International Electrical Congress, the writer presented a paper on the “Leakage Reactance of Induction Motors,” in which a new leakage element was described, with results of experiment and calculation. A method of calculating the other leakage elements was also outlined. This method, based upon fundamental principles, was checked by a long series of experiments, and while not new fundamentally, may have some points of novelty in its details. In the present paper this method will be more fully developed and applied to the design of Induction Motors. The leakage elements will be expressed in a novel form and a new method will be employed for the calculation of the power factor. A method of calculating the exciting current will be given with corroborative data. Some new design constants will also be developed.