The Student's Text-book of ElectricityC. Lockwood, 1879 - 615 páginas |
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action apparatus appearance armature arrangement attached attracted axis ball bismuth brass cable carbon cells centre charge Chatterton's compound circuit coating coil conducting conductor connected copper copper wire core current passes cylinder deflection diamagnetic direction disc discharge distance earth effect elec electric current electrified electro-magnet electrode electrometer electromotive force electroscope employed equal experiments Faraday feet fixed fuse galvanometer gutta-percha heat helix hydrogen inch in diameter increased induction instrument insulated intensity iron wire length lever Leyden jar light machine magnetic magnetised magneto-electric mercury metallic miles motion needle negative electricity nitric acid observed obtained opposite oxygen particles piece placed platinum platinum wire polarised polarity poles positive electricity produced quantity of electricity resistance rotation round screw shown in Fig side soft iron solution spark sulphate sulphuric acid surface telegraph tension terminals tion tricity voltaic battery voltaic current wire zinc zinc plate
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Página 455 - But Moses' hands were heavy; and they took a stone, and put it under him, and he sat thereon; and Aaron and Hur stayed up his hands, the one on the one side, and the other on the other side; and his hands were steady until the going down of the sun.
Página 156 - ... be produced which shall go on for ever against a constant resistance, or only be stopped, as in the voltaic trough, by the ruins which its exertion has heaped up in its own course. This would indeed be a creation of power, and is like no other force in nature. We have many processes by which the form of the power may be so changed, that an apparent conversion of one into the other takes place.
Página 287 - Tyndall accordingly concludes that " if the arrangement of the component particles of any body be such as to present different degrees of proximity in different directions, then the line of closest proximity, other circumstances being equal, will be that chosen by the respective forces for the exhibition of their greatest energy. If the mass be [para] magnetic, this line will stand axial; if diamagnetic, equatorial."2 1 Tyndall on Diamagnetism, p.
Página 320 - ... pair of bearings was sufficient instead of two, and the machine altogether was much simplified. The machine now about to be described is a still further modification, in which the greatest amount of simplicity and effective power are combined. The apparatus consists essentially of an electro- magnet, with -shoes forming a groove, in which a Siemens armature is made to revolve.
Página 18 - For though all the particles in the line of induction resist charge, and are associated in their actions so as to give a sum of resisting force, yet when any one is brought up to the overturning point, all must give way in the case of a spark between ball and ball.
Página 84 - ... The wind blew with great violence, momentarily changing its direction, as if it were sweeping round in short spirals: the rain which fell in torrents was also precipitated in curves, with short intervals of cessation. Amidst this thick shower, the waterspout was discovered, extending in a tapering form, from a dense stratum of cloud to within thirty feet of the water, where it was hid by the foam of the sea being whirled upwards by a tremendous gyration.
Página 201 - Solution of sulphate of potash was placed in contact with the negatively electrified point, pure water was placed in contact with the positively electrified point, and a weak solution of ammonia was made the middle link of the conducting chain ; so that no sulphuric acid could pass to the positive point in the distilled water, without passing through the solution of ammonia. The...
Página 245 - The other forces are easily obtained by the proportions : — 1-5 : 5=a : x=— a=3-333 a 1*5 (that is to say, one reduced current is to the total current to which it corresponds, as any other reduced current is to its corresponding total current), where a represents the deflection when the exterior circuit is closed. We thus obtain — 5, 10, 15-2, 21, 28, 37-3, for the forces corresponding to the deflections — 5°, 10°, 15°, 20°, 25°, 30°.
Página 208 - The tube was suspended by a piece of platina wire, so that the heat of a spirit-lamp could be applied to it. Recently fused protochloride of tin was introduced in sufficient quantity to occupy, when melted, about one-half of the tube; the wire of the tube was connected with a volta-electrometer, which was itself connected with the negative end of a voltaic battery: and a platina wire connected with the positive end of the same battery was dipped into the lg...
Página 74 - While the thunder-cloud is swelling and extending itself over a large tract of country, the lightning is seen to dart from one part of it to another, and often to illuminate its whole mass. When the cloud has acquired a sufficient extent, the lightning strikes between the cloud and the earth in two opposite places, the path of the lightning lying through the whole body of the cloud and its branches. The longer this lightning continues, the rarer...