Lessons in practical electricity; principles, experiments, and arithmetical problems, an elementary text-book (1902)
Swoope, Coates Walton. [from old catalog] · New York, D. Van Nostrand company · leaf 208
quite strong between thepoles of the electromagnet. In-stead of a forged horseshoe itmay be composed of threeparts, as in Fig. 180, where thetwo iron cores or limbs areconnected by an iron yoke ofequal cross section and secured by machine screws. Thedirection of current and resulting polarity are… … Fig. 180.—Direction of CurrentAround Horseshoe Magnet.
Electricity · Magnetism
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