. The principles of physics. insulated wire, the ends of which are connected with thebinding screws, D D. Immediately in front of the magnet isa thin circular iron disk, E E. The whole is enclosed in awooden or rubber case, F. The conical-shaped cavity, G,serves the purpose of either a mouth-piece or an is no difference between the transmitting and the re-ceiving telephone; consequently, either instrument may beemployed as a transmitter, while the other serves as a re-ceiver. Two magneto-telephones in a circuit are Virtually 600 ETHER DYNAMICS. in tlie relation of a dynamo an
. The principles of physics. insulated wire, the ends of which are connected with thebinding screws, D D. Immediately in front of the magnet isa thin circular iron disk, E E. The whole is enclosed in awooden or rubber case, F. The conical-shaped cavity, G,serves the purpose of either a mouth-piece or an is no difference between the transmitting and the re-ceiving telephone; consequently, either instrument may beemployed as a transmitter, while the other serves as a re-ceiver. Two magneto-telephones in a circuit are Virtually 600 ETHER DYNAMICS. in tlie relation of a dynamo and a motor. The transmitterbeing in itself a diminutive dynamo, of course no battery isrequired in the circuit. Connect in circuit two such tele-phones, and the apparatus is ready for use. When a person talks near the disk of the transmitter, hethrows it into rapid vibration. The disk, being quite closeto the magnet, is magnetized by induction ; and as it vibrates,its magnetic power is constantly changing, being strengthened. Fig. 486. as it approaches the magnet, and enfeebled as it fluctuating magnetic force will of course induce currentsin alternate directions in the neighboring coil of wire. Thesecurrents traverse the whole length of the wire, and so passthrough the coil of the distant instrument. When the direc-tion of the arriving current is such as to increase the intensityof the magnetic field of the receiver, the magnet attracts theiron disk in front of it more strongly than before. When thecurrent is in the opposite direction, the disk is less attracted,and flies back. Hence the disk of the receiving telephone is BELL TELEPHONE. 601 forced to repeat whatever movement is imparted to the diskof the transmitting telephone. The vibrations of the formerdisk become sound in the same manner as the vibrations of atuning-fork or of the head of a drum. The above is a description of the original and simplestform of the Bell telephone. It is apparent that the original
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectphysics, bookyear1895
