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 17
... copper wire passed through part of the dorsal column remaining above the junc- tion of the thighs , it all at once underwent a series of lively convulsions . The professor was more than ever astonished , for there was this time no ...
... copper wire passed through part of the dorsal column remaining above the junc- tion of the thighs , it all at once underwent a series of lively convulsions . The professor was more than ever astonished , for there was this time no ...
Página 18
... copper and iron , in the experiment of Galvani , were the real electromotors , and that the muscles of the dead frogs only played the part of a moist conductor in completing the circuit . Volta was of opinion that the simple contact of ...
... copper and iron , in the experiment of Galvani , were the real electromotors , and that the muscles of the dead frogs only played the part of a moist conductor in completing the circuit . Volta was of opinion that the simple contact of ...
Página 19
... copper , then on this a disc of zinc , and over these a similar sized disc of damp cloth ; and by continuing to pile discs of these materials , in the same order , copper , zinc , cloth , until he had a sufficient number . He then ...
... copper , then on this a disc of zinc , and over these a similar sized disc of damp cloth ; and by continuing to pile discs of these materials , in the same order , copper , zinc , cloth , until he had a sufficient number . He then ...
Página 20
... copper disc at the bottom . These experiments may be repeated ad infinitum even after the pile has been mounted some hours , provided the cloth retains some moisture . 3rd . It produces chemical effects with an energy propor- tional to ...
... copper disc at the bottom . These experiments may be repeated ad infinitum even after the pile has been mounted some hours , provided the cloth retains some moisture . 3rd . It produces chemical effects with an energy propor- tional to ...
Página 22
... copper wires insulated with silk , passing through the tube E of glass or porcelain to the transmitting station . Here the wires , marked with the respective letters and numerals , were insulated on a wooden support , K K. The ends of ...
... copper wires insulated with silk , passing through the tube E of glass or porcelain to the transmitting station . Here the wires , marked with the respective letters and numerals , were insulated on a wooden support , K K. The ends of ...
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Términos y frases comunes
alphabet alternate currents armature arrangement atmospheric electricity attracted axis back contact beam cable clockwork closed coils of relay commutator connected consists construction contact peg contact-point copper core corresponding counteracting battery current passes currents arriving cylinder deflected dial direction disc discharge earth electric telegraph electricity electro-magnet employés frictional electricity galvanic galvanometer galvanoscope gutta percha holes horizontal inductor inserted insulated intermediate station interrupted length letters Leyden jar line battery line wire line-wire local battery magneto-electric means metal Morse apparatus motion needle negative current opposite station paper strip permanent magnet plate pointer polarised relay poles positive current posts pressed ratchet-wheel ratus receiving instrument receiving station reposing contact rest roller screw sending station shaft shown in Fig side Siemens signals soft-iron spiral spring style surface switch teeth telegraph terminal TERMINAL STATION tion tongue tooth tube turning type-wheel underneath vertical vulcanite wheel whilst zinc
Pasajes populares
Página 11 - In electricity he has made a remarkable discovery : you write two or three words on a paper ; he takes it with him into a room, and turns a machine inclosed in a cylindrical case, at the top of which is an electrometer, a small fine pith ball; a wire connects with a similar cylinder and electrometer in a distant apartment ; and his wife, by remarking the corresponding motions of the ball, writes down the words they indicate : from which it appears that he has formed an alphabet of motions. As the...
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 30 - When the contact was made, there was a sudden and very slight effect at the galvanometer, and there was also a similar slight effect when the contact with the battery was broken.
Página 8 - An expeditious method of conveying intelligence." wire, from one place to another, without being sensibly abated by the length of its progress. Let, then, a set of wires, equal in number to the letters of the alphabet, be extended horizontally between two given places, parallel to one another, and each of them about an inch distant from that next to it. At every twenty yards...
Página 9 - The same thing may be otherwise effected. Let the balls be suspended over the characters as before, but instead of bringing the ends of the horizontal wires in contact with the barrel, let a second set reach from the electrified...
Página 259 - ... the art of directing the great sources of power in nature for the use and convenience of man, as the means of production and of traffic in states.
Página 29 - Certain effects of the induction of electrical currents have already been recognized and described: as those of magnetization; Ampere's experiments of bringing a copper disc near to a flat spiral; his repetition with electro-magnets of Arago's extraordinary experiments, and perhaps a few others. Still it appeared unlikely that these could be all the effects which induction by currents could produce; especially as, upon dispensing with iron...
Página 201 - Lille and back, making a total distance of 336 miles. This, however, not being deemed sufficient for the purpose, several coils of wire wrapped with silk were obtained, measuring in their total length 746 miles, and were joined to the extremity of the wire returning from Lille; thus making one continuous wire measuring 1,082 miles.
Página 9 - To prevent this objection, and save longer argument, lay over the wires from one end to the other with a thin coat of jeweller's cement. This may be done for a trifle of additional expense, and, as it is an electric per se, will effectually secure any part of the fire from mixing with the atmosphere. I am, etc., CM...
Página 8 - At every twenty yards' end, let them be fixed in glass, or jeweller's cement, to some firm body, both to prevent them from touching the earth, or any other nonelectric, and from breaking by their own gravity. Let the electric gun-barrel be placed at right angles with the extremities of the wires, and about an inch below them. Also let the wires be fixed in a solid piece of glass, at six inches from the end ; and let that part of them which reaches from the glass to the machine have sufficient spring...