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apparatus attract axis bisulphide brass calculate called charge of electricity coil conductor connected to earth curved lines cylinder deflection dielectric different insulators direction discharge distance duction ebonite elec electric induction electric machine electric strain electrified body electro-magnetic induction electro-static electrometer electroscope ether exactly equal experiment Extra dense flint Faraday galvanometer Grove cells gutta-percha horizontal inch induced charge induces electricity induction balance inductive actions kinetic energy knob lecture Leyden jar light-spot lines of force magnetic induction Maxwell means measure medium metal method motion move needle negative optical outer paraffin periments phenomena plates polarization poles positive pressure prisms produced quadrants ratio residual charge reversing screen screw sealing-wax seen selenium shellac shown space spark specific inductive capacity strain or distortion straining force substance sulphur take place thickness tinfoil tion torsion balance tricity turn twisted velocity of light vertical vibrations wave wire zero
Page 51 - Hence the specific inductive capacity of a substance is the ratio of the capacity of a condenser when its plates are separated by this substance to the capacity of the same condenser when its plates are separated by air.
Page 48 - ... the electrified bodies, and leads, when continually augmented, to disruptive discharge. Electric tension, in this sense, is a tension of exactly the same kind, and measured in the same way, as the tension of a rope, and the dielectric medium, which can support a certain tension and no more, may be said to have a certain strength in exactly the same sense as the rope is said to have a certain strength. Thus, for example, Thomson has found that air at the ordinary pressure and temperature can support...
Page 1 - Amongst the actions of different kinds into which electricity has conventionally been subdivided, there is, I think, none which excels, or even equals in importance that called Induction. It is of the most general influence in electrical phenomena, appearing to be concerned in every one of them, and has in reality the character of a first, essential, and fundamental principle. Its comprehension is so important, that I think we cannot proceed much further in the investigation of the laws of electricity...
Page 125 - Possibly a clue to the nature of this disturbing cause may be found in the fact, that the specific inductive capacities are affected by some of the changes which chemists tell us are constantly going on in glasses, but that these changes do not affect the refractive indices.
Page 4 - ... although we have, or think we have, tolerably clear ideas of the character of the motion of heat, our ideas are very unclear as to the precise nature of the change which this motion must undergo in order to appear as electricity ; in fact, we know as yet nothing about it." Gordon wrote, " We have as yet no conception of electricity apart from the electrified body ; we have no experience of its independent existence.
Page 2 - ... Induction. It is of the most general influence in electrical phenomena, appearing to be concerned in every one of them, and has in reality the character of a first, essential, and fundamental principle. Its comprehension is so important, that I think we cannot proceed much further in the investigation of the laws of electricity without a more thorough understanding of its nature ; how otherwise can we hope to comprehend the harmony and even unity of action which doubtless governs electrical excitement...
Page 137 - ... 14 inches diameter. In about two seconds more these vanished and were succeeded by a huge black cross about 3 feet across, seen on a faintly luminous ground. The arms of the cross were along the planes of polarization, and therefore (the experiment being arranged according to Dr.
Page 3 - ... been in contact with the flannel. enormous number of effects of the most varied kinds. The example we have selected, where electrical effects are produced by rubbing two dissimilar bodies against each other, is the oldest electrical experiment known to science. The sealing-wax and the flannel are said to be electrified, or to be in a state of electrification, or to be charged with electricity ; and the region in which the attractions and repulsions are observed is called the electric field. 2....
Page 22 - No ; for an exactly equal quantity of negative electricity was produced on the rubber, as I can show you. (The rubber, on being laid on the electroscope, caused a strong divergence of the leaves.) To show that this negative is equal to the positive, a very simple experiment will suffice. I rub this sealing-wax till, by the cracking, you can hear that it is highly electrified, but do not remove the rubber from it. You see there is no effect on the electroscope.