Elements of Physics: Imponderable bodies. I. Light, heat, and magnetism

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Longman, Brown, Green, and Longmans, 1846
 

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Pagina 156 - Finally, I may say that the cause of the evolution of electricity by the liberation of confined steam is not evaporation ; and further, being, I believe, friction, it has no effect in producing, and is not connected with, the general electricity of the atmosphere...
Pagina 100 - ... passing from the solid to the liquid, and from the liquid to the gaseous form, or the contrary, occasioning endless vicissitudes of temperature over the globe.
Pagina 236 - Cells thus placed are said to be arranged in series. When thus arranged, the electromotive force of each cell is added to that of its neighbor, and the resulting electromotive force is equal to the sum of the electromotive forces of all the cells. Assuming the EMF of each cell in Fig. 13 to be i volt, the total EMF developed...
Pagina 224 - ... the soft iron is exactly proportional to that of the electric current. 2. The intensity of the current continuing the same, the magnet's suspensive power increases with the number of turns made by the wire, or, the total effect of all the coils is equal to the sum of their effects if taken singly. 3. The attractive force of an electro-magnet increases as the mass of the iron composing it, and this increase is proportional to the diameter of the iron cylinder, their lengths being equal.
Pagina 225 - ... the iron influences its suspensive power. Cylinders carry greater weights than rectangular bars ; and a hollow cylinder from which a portion has been cut away, so as to form a long horse-shoe magnet when viewed in the direction of its axis, but a very short one if taken as to its height, is capable of receiving a very great suspensive force; and lastly, a slight curvature of the polar surface adds considerably to its power. At the moments of magnetization and demagnetization of iron bars, peculiar...
Pagina 115 - ... in its weight, and becomes rather denser at the points. The phenomenon is attended with a still more vivid brightness, if the ch rcoal points are placed in a vacuum, or in any of those gases which are not supporters of combustion. Instead of two charcoal points, one only need be used if the following arrangement is adopted ; lay the piece of charcoal on some quicksilver that is connected with one pole of the battery, and complete the circuit from the other pole by means of a strip of platinum.
Pagina 137 - ... copper begins to be dissolved, the copper anode is removed, and its place supplied with one of zinc ; after the action has continued for some little time, brass will be liberated on the cathode. The solution is now ready for use, and is operated upon by two or three Daniell's cells, and with a brass anode. By similar means alloys of gold and copper, or gold and silver, may be deposited. The author reasons, that true brass is a definite chemical compound, and states, it appears possible that the...
Pagina 116 - ... very small. So, also, we can easily explain why these effects are rendered still more powerful, if that portion of the human frame which is enclosed within the wires...
Pagina 137 - The process adopted, is to prepare a strong solution of cyanide of potassium, and commence electrolyzing it, by means of a copper anode; as soon as copper begins to be dissolved, the copper anode is removed, and its place supplied with one of zinc; after the action has continued for some little time, brass will be liberated on the cathode. The solution is now ready for use, and is operated...
Pagina 156 - ... cause of the evolution of electricity by the liberation of confined steam is not evaporation ; and further, being, I believe, friction, it has no effect in producing, and is not connected with, the general electricity of the atmosphere : also, that as far as I have been able to proceed, pure gases, ie gases not mingled with solid or liquid particles, do not excite electricity by friction against solid or liquid substances*.

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