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agate point alphabet alternate currents armature arrangement attracted axis back contact beam cable carried clockwork commutator connected construction contact-point copper cores corresponding current passes currents arriving cylinder deflected dial direction disc earth electric telegraph electricity electro-magnet employed frictional electricity galvanic galvanometer galvanoscope gutta percha holes horizontal inductor inserted insulated intermediate station interrupted invention iron length letters lever Leyden jar lifted line battery line wires line-wire local battery magnetic needle magneto-electric means metal millimetre Morse apparatus motion negative current oscillating paper strip permanent magnet plate pointer polarised relay poles positive current posts pressed printing printing-disc ratchet-wheel ratus receiving instrument receiving station relay released reposing contact rest roller rotating round scape-wheel screw sending station shaft shown in Fig side Siemens signals soft-iron spiral spring style surface switch teeth terminal tion tongue tooth tube turning type-wheel underneath upper vertical voltaic Wheatstone wheel whilst zinc
11 ページ - 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...
30 ページ - 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.
8 ページ - 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...
9 ページ - 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...
259 ページ - ... 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.
29 ページ - 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...
201 ページ - 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.
9 ページ - 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...
8 ページ - 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...