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action amount ampères appears armature arrangement battery bismuth cable carbon cause cell charge circuit coil conductor connected considerable consists constant continuous copper cylinder deflection difference direction discharge distance disturbances dynamo earth currents effect electricity electro-motive force energy Engineers equal experiments fact field fixed force galvanometer give given grammes greater heat important increase induction interesting iron lamps lead length less light lines London machine magnetic matter means measure meeting metal meter microphone motor nature observations obtained ohms ordinary passing placed plate points position potential practical present President pressure produced Professor proportional quantity question record remarks resistance rotation shown Society sound speed storm strength supply surface taken Telegraph telephone theory transmitter unit varying vibrations volts weight wire
Página 374 - ... such as magnetism and electricity. 3. That the inherent polarity or magnetism of each molecule is a constant quantity like gravity ; that it can neither be augmented nor destroyed. 4. That when we have external neutrality, or no apparent magnetism, the molecules or their polarities arrange themselves so as to satisfy their mutual attraction by the shortest path, and thus form a complete closed circuit of attrac tion.
Página 265 - The value of frequently testing the apparatus and circuits cannot be too strongly urged. The escape of electricity cannot be detected by the sense of smell, as can gas, but it can be detected by apparatus far more certain and delicate. Leakage not only means waste, but in the presence of moisture it means destruction of the conductor and its insulating covering, by electric action.
Página 94 - The force acting on the armature of an electro-magnet, in any position, is proportional to the square of the current ; (2) the square of the number of vibrations, say, of a pendulum, is a measure of the controlling force. Therefore, If the controlling force under which a body vibrates is due to the action of an electro-magnet on its armature, the square of the number of vibrations in a given time is a measure of the square of the electric current. In other words, the rate of vibrating is a measure...
Página 263 - The difficulties that beset the electrical engineer are chiefly internal and invisible, and they can only be effectually guarded against by " testing," or probing with electric currents. They depend chiefly on leakage, undue resistance in the conductor, and bad joints, which lead to waste of energy and the dangerous production of heat.
Página 372 - If we admit the assumption of electric currents around each molecule, the molecule itself would then be electromagnetic, and the question still remains, What is polarity ? Have the supposed electric currents separated the two assumed magnetic fluids contained in the molecule, as in Poisson's theory?
Página 251 - Letter to Captain Huish, as to proposed improvements in the Electric Telegraph System, for the service of the L.
Página 245 - I found that one ounce of lead was not sufficient on a surface of contact 1 centim. square to maintain constant^ contact ; and it was only by removing the musical box to a distance of several feet that I was enabled to preserve continuity of current with a moderate pressure. I have spoken to forty microphones at once ; and they all seemed to respond with equal force. Of course there must be a loss of energy in the conversion of molecular vibrations into electrical waves...
Página 372 - The whole of the magnetic molecular phenomena that we have been studying lead us to believe that the magnetization of a body is due to a particular arrangement of its molecules, originally endowed with magnetic virtue, but which in the natural state are so arranged that the magnetism of the body that they constitute is not apparent. Magnetism would, therefore, consist in disturbing this state of equilibrium, or in giving to the particles an arrangement that makes manifest the property with which...