The History and Progress of the Electric Telegraph: With Descriptions of Some of the ApparatusD. Van Nostrand, 1869 - 280 páginas |
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Página 52
... beam supporting two armatures of soft iron , over the poles of two electro - magnets , in the circuits of the two line wires . As the tooth - wheel of the transmitter was turned round , currents were alternately sent through the side ...
... beam supporting two armatures of soft iron , over the poles of two electro - magnets , in the circuits of the two line wires . As the tooth - wheel of the transmitter was turned round , currents were alternately sent through the side ...
Página 58
... beam of light reflected by the mirror is thrown . The mirror and magnet being very light , are deflected by weak currents , and their distance from the scale being sufficiently great , very small deflections can be read off with ...
... beam of light reflected by the mirror is thrown . The mirror and magnet being very light , are deflected by weak currents , and their distance from the scale being sufficiently great , very small deflections can be read off with ...
Página 66
... beam is provided with a button or knob , which the operator takes in his hand and presses when he wishes to give a signal , by depressing the fore part of the beam upon the front or working contact . In France , M. Villette has lately ...
... beam is provided with a button or knob , which the operator takes in his hand and presses when he wishes to give a signal , by depressing the fore part of the beam upon the front or working contact . In France , M. Villette has lately ...
Página 74
... beam . By this means the extremity of the beam may be raised very quickly , allowing the weight to drop and the cord to run over the axis ; but it cannot be lowered without first turning the wheel , pinion , and fly , and raising the ...
... beam . By this means the extremity of the beam may be raised very quickly , allowing the weight to drop and the cord to run over the axis ; but it cannot be lowered without first turning the wheel , pinion , and fly , and raising the ...
Página 75
... beam shall take some time to return to its position of rest , and that during the greater part of this time the spring , f , shall remain in contact with the screw , w , in connection with the reverse battery . SWITCH wif u A SWITCH- Ο ...
... beam shall take some time to return to its position of rest , and that during the greater part of this time the spring , f , shall remain in contact with the screw , w , in connection with the reverse battery . SWITCH wif u A SWITCH- Ο ...
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Términos y frases comunes
alphabet alternate currents armature arrangement atmospheric electricity attracted axis back contact beam bottom cable carried clockwork coils commutator connected consists construction contact-pins copper core corresponding current passes currents arriving cylinder deflected dial direction disc drum electricity electro-magnet employés galvanic galvanometer galvanoscope gutta percha hemp holes horizontal inductor inserted insulated intermediate station interrupted iron wires knot length letter lever Leyden jar lifted line battery line wire line-wire local battery means Messrs metal method mètre Morse apparatus motion needle negative current opposite paper strip permanent magnet plate pointer poles positive current posts pressed printing printing-press ratchet-wheel ratus receiving station relay resistance roller rotating round scape-wheel screw sending station shaft shown in Fig side Siemens signals soft-iron spiral spring style surface switch synchronism teeth terminal tion tongue tooth transmitting tube turning type-wheel underneath upper vertical vulcanite wheel whilst wire zinc
Pasajes populares
Página 5 - he felt himself struck in his arms, shoulders, and breast, so that he lost his breath, and was two days before he recovered from the effects of the blow and the terror.
Página 11 - ... and his wife, by remarking the corresponding motions of the ball, writes down the words they indicate: from which it appears he has formed an alphabet of motions. As the length of the wire makes no difference in the effect, a correspondence might be carried on at any distance...