. The principles of physics. ter to vibrateand reproduce sounds. The next improvement of considerable importance consistsin the adoption of an induction coil, which, we have learned,produces a current of much greater electro-motive force thanis possessed by the original battery current. By its adoptionwe are able to converse over much longer distances, and sincethe battery current traverses only a local circuit, as may beseen by reference to Fig. 488, a single Leclanche cell is gener-ally sufficient to operate it. The currents induced by thefluctuating primary current traverse the line wire an
. The principles of physics. ter to vibrateand reproduce sounds. The next improvement of considerable importance consistsin the adoption of an induction coil, which, we have learned,produces a current of much greater electro-motive force thanis possessed by the original battery current. By its adoptionwe are able to converse over much longer distances, and sincethe battery current traverses only a local circuit, as may beseen by reference to Fig. 488, a single Leclanche cell is gener-ally sufficient to operate it. The currents induced by thefluctuating primary current traverse the line wire and generatesonorous vibrations in the disk of the receiver in the samemanner as in the original telephone. Fig. 489 represents the entire telephonic apparatus requiredat any single station. The box A contains a small hand-dynamo, such as is represented in Fig. 490. A person turn- MICROPHONE. 603 ing the crank F generates a current which rings a pair ofelectric bells G, both at his own and at a distant station, and gflmnrfWlrf.
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectphysics, bookyear1895
