Twentieth century handbook for steam engineers and electricians, with questions and answers; a practical nontechnical treatise .. (1916)
Swingle, Calvin F. (Calvin Franklin), b. 1846 · Chicago, F.J. Drake & company · leaf 1071
d, andthe more turns of wire we arrange to cut those lines of forceper second the greater will be the E. M. F. Instead of pro-viding more wire or increasing the speed of the armaturewe can increase the magnetism, or number of lines of force,by sending more current through the fields, that is… … Fig. 428use of collecting or slip rings
