Twentieth century handbook for steam engineers and electricians, with questions and answers; a practical nontechnical treatise on the care and management of steam engines, boilers and electric machinery (1922)
Swingle, Calvin Franklin, 1846- [from old catalog] · Chicago, F. J. Drake & company · leaf 1066
e indirectly expended in maintaining the fieldof a dynamo^ for the reason that an electro-magnet is pre-ferred to a natural magnet in such a machine, because byits use the dynamo may be made much smaller and lighter. An electro-motive force is induced by rapidly cuttinglines of force, that is, by… … wind about it a few turns of wire and cause a current ofelectricity to flow along the wire. Fig. 425. The magnetismis conceived to consist of lines of force, which leave thebar at one end and enter it at the other, the direction ofthese lines depending upon the direction in which the cur-rent…
![An illustration from [Electric engineering.] (1902)](https://img.insideoutlibrary.com/img/200/ia-electricengineer02inte-144-59.webp)
