Lectures on Electricity: Comprising Galvanism, Magnetism, Electro-magnetism, Magneto- and Thermo-electricityG. Knight, 1844 - 457 sider |
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apparatus appearance arrangement attraction axis barytes body brass ball cells centre charge chemical action circuit cloud coating coil communication conducting connected copper wire cylinder decomposed decomposition dilute direction disc discharge disruptive discharge distance earth effect Elec electric current electrified electro-magnet electrode electrolyte electrometer electroscope employed evolved excited exhibited experiments extremity Faraday feet fluid force galvanic galvanometer glass tube heat helix hydrogen increased induction insulated intensity knob length Leyden jar light machine magnetic mercury metallic motion needle negative nitric acid north pole observed obtained opposite oxide oxygen pairs particles pass phenomena piece platinum platinum wire polarity positive Electricity prime conductor produced quantity of Electricity screw shock shown in Fig side silver soft iron solution south pole spark substance sulphuric acid surface takes place thick tion tricity voltaic battery voltaic pile wire zinc
Populære passager
Side 174 - ... the atoms of matter are in some way endowed or associated with electrical powers, to which they owe their most striking qualities, and amongst them their mutual chemical affinity.
Side 172 - I at first laid down, namely, that the chemical power of a current of electricity is in direct proportion to the absolute quantity of electricity which passes (377, 783).
Side 249 - The focus of violet rays was carried slowly along the needle, proceeding from the centre towards one of the extremities, care being taken never to go back in the same direction, and never to touch the other half of the needle. At the end of half an hour, after the needle...
Side 242 - ... 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 another takes place.
Side 1 - It is not easy to say, whether we are most pleased with the simplicity and perspicuity with which these letters are written, the modesty with which the author proposes every hypothesis of his own, or the noble frankness with which he relates his mistakes, when they were corrected by subsequent experiments.
Side 202 - The removal of dyspnoea, as stated above, led him to try galvanism as a remedy in asthma. By transmitting its influence from the nape of the neck to the pit of the stomach, he gave decided relief in every one of twenty-two cases, of which four were in private practice, and eighteen in the Worcester InBrmary.
Side 293 - ... all those planets whose internal structure admits of such a difference. Yet, allowing all this, the main difficulty seems not to be overcome, but merely removed from the eyes to a greater distance ; for the question may still be asked, with equal justice, whence did the sun acquire its magnetic force ? And if from the sun we have recourse to a central sun, and from that again to a general magnetic direction throughout the universe, having the Milky Way for its equator, we but lengthen an unrestricted...
Side 248 - The needle was made of soft iron, and was found, upon trial, to possess neither polarity nor any power of attracting iron filings. It was fixed horizontally upon a support by means of wax, and in such a direction as to cut the magnetic meridian at right angles. The focus of violet...
Side 200 - ... every muscle in his countenance was simultaneously thrown into fearful action ; rage, horror, despair, anguish, and ghastly smiles, united their hideous expression in the murderer's face, surpassing far the wildest representations of a Fuseli or a Kean. At this period several of the spectators were forced to leave the apartment from terror or sickness, and one gentleman fainted.