Twentieth century hand-book for steam engineers and electricians, with questions and answers .. (1905)
Swingle, C. F. [from old catalog], Horstmann, Henry Charles, 1858- [from old catalog], Tousley, Victor Hugo, 1875- [from old catalog] · Chicago, F. J. Drake & co. · leaf 549
figure 74. tages over them. In the two phase system two cur-rents displaced 90 degrees from each other andotherwise exactly similar to the single phase currentsare used. In the three phase system three currentsseparated 120 degrees are used. These currents areshown in Fig. 74.
