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 346
mitter is practically analternating current dynamo,driven by the energy of thehuman voice, while the re-ceiver is a motor driven bythe current from the gen-erator. 311. The MicrophonePrinciple.—A microphoneis a device for renderingfaint or distant sounds dis-tinctly audible, and is used in many… … Fig. 296.—Apparatus to Illustrate the Princii>le of the Microphone. 328 PRACTICAL ELECTRICITY. are two carbon buttons one of which is fastened to a thinpine wood sounding board and the other to a brass spring, S,which causes B to touch A. The ■ buttons are connected incircuit with a telephone…
Electricity · Magnetism
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
![An illustration from The Telegrapher [microform] (1864)](https://img.insideoutlibrary.com/img/200/ia-telegrapher05nati-320-204.webp)
![An illustration from [Electric engineering.] (1902)](https://img.insideoutlibrary.com/img/200/ia-electricengineer03inte-331-203.webp)
