Electric field

“ We want to obtain our power as direct from the engine to the dynamo as possible, and at the same time as cheaply, and obtain the best economy under the variable loads we are going to have. We cannot design our plant for that capacity which is reached as shown on our load diagram, for only a short time in the twenty-four hours, but we must so design it to give this result for the average that we have during the twenty-four hours. ”

“ We have, therefore, here, in a building 75 × 100 feet, apparatus and all departments complete for the generation and supply of current and power for a capacity of 40,000 lights, or the equivalent in light and power, and so arranged as to secure, as far as can be foreseen, continuous working of the plant and entire reliability in the furnishing of its current. ”

“ The most obvious mechanical phenomenon in electrical and magnetical experiments is the mutual action by which bodies in certain states set each other in motion while still at a sensible distance from each other. The first step, therefore, in reducing these phenomena into scientific form, is to ascertain the magnitude and direction of the force acting between the bodies, and when it is found that this force depends in a certain way upon the relative position of the bodies and on their electric or magnetic condition, it seems at first sight natural to explain the facts by assuming the existence of something either at rest or in motion in each body, constituting its electric or magnetic state, and capable of acting at a distance according to mathematical laws. ”

“ In the Edison underground system we have what is generally recognized as the most practical solution for circuits of less than 400 to 500 volts. We here obtain at a premium of cost the most flexible system and local distribution from house to house, which has no equal It enables you to take off services for local distribution from every twenty feet without in any way affecting the insulation on the main line, and being able at any time to disconnect these services and restore the main to its original condition. ”

“ It is greater, for instance, in dense air than in rare air, and greater in glass than in air, but in every case, if the electromotive force be made great enough, the dielectric gives way and its insulating power is destroyed, so that a current of electricity takes place through it. It is for this reason that distributions of electricity for which the electric resultant force becomes anywhere infinite cannot exist in nature. ”

“ We have seen how the simple glass cylinder or sulphur roll became, when rubbed, a generator of electricity. In a later chapter of electrical history, we saw a new and more powerful generator of electricity in the voltaic cell, by means of opposing metals acted upon chemically by acids. The greatest, grandest, most powerful, and most economic of all generators of electricity was yet to come in the shape of the dynamo. We see its beginnings in those investigations of Faraday which led to the discovery of the induction coil and the principles of magneto-electric induction. ”

“ In endeavoring to adapt currents or discharges of very high tension to various valuable uses, as the distribution of energy through wires from central plants to distant places of consumption, or the transmission of powerful disturbances to great distances, through the natural or non-artificial media. I have encountered difficulties in confining considerable amounts of electricity to the conductors and preventing its leakage over their supports, or its escape into the ambient air, which always takes place when the electric surface density reaches a certain value. ”

“ When they are worked from a power station the great advantage is gained that the same plant which drives them can be used for many other purposes, such as working machine tools and supplying current for lighting. For dock-side jib cranes the use of electric power is making rapid strides. For overhead travellers in workshops, and for most of the cranes which fall into our second class, electricity as a motive power has already displaced nearly every other method. ”

“ The earliest instance of applying Electricity to the production of light was in 1810, by Sir Humphrey Davy, who found that when the points of two carbon rods whose other ends were connected by wires with a powerful primary battery were brought into contact, and then drawn a little way apart, the Electric current still continued to jump across the gap, forming what is now termed an Electric Arc. ”

“ Where currents of any magnitude are required, we must use other methods of producing electricity. These will be discussed subsequently, but for the present it is important to note that, apart from a question of degree, the frictional machine is an apparatus whereby electric currents may be generated.
How does the matter stand with regard to electrification by contact between solid bodies? Can we thereby also produce an electric current? We have seen that two metals in contact electrify each other. Using copper and zinc, the former becomes negatively and the latter positively electrified ”

“ Electricity as an illuminant and for all possible purposes is so cheaply procured as to be within the means of all requiring its use. Throughout the irrigated belt and on most portions of Ento there are Stations where thoroughly trained persons attend to the production and distribution of electric currents, and so valued is life that accidents are of very rare occurrence. ”

“ Suppose water power to be employed to give motion to a dynamo-electrical machine, a very powerful electrical current will be the result, which may be carried to a great distance, through a large metallic conductor, and then be made to impart motion to electromagnetic engines, to ignite the carbon points of electric lamps, or to effect the separation of metals from their combinations. ”

“ The electrical glow is therefore produced by the constant passage of electricity through a small portion of air in which the tension is very high, so as to charge the surrounding particles of air which are continually swept off by the electric wind, which is an essential part of the phenomenon.
The glow is more easily formed in rare air than in dense air, and more easily when the point is positive than when it is negative. This and many other differences between positive and negative electrification must be studied by those who desire to discover some thing about the nature of electricity. ”

“ The generator of the electric current, which is stored away in some out-of-the-way corner, is probably a small so-called "dry-cell" which you could readily carry around in your pocket; or it may consist of a receptacle holding a pint or two of liquid in which some metal plates are immersed. Such an apparatus seems scarcely more than a toy when we contrast it with the gigantic dynamos of the power-house; yet, within the limits of its capacities, one is as surely a generator of electricity as the other. ”

“ Even though it goes back and forth in waves of tremendous rapidity, you can see that there must be a time in this period when the electricity is for an infinitesimal space of time at low power, and another infinitesimal space of time at high. In order to keep the supply even and steady, two and sometimes three coils of wire are used in the generator to catch the electricity so that there is scant opportunity for the electric supply to be anything but even, for when one coil is up the other is down and thus they even up the strength of the current. ”

“ Although there is a variety of ways of producing electricity, from the rubbing of a piece of sealing-wax on the coat-sleeve to the vast engines employed at large central lighting-stations, yet here we will consider only such methods of producing the force as are in practical use on a moderate scale. The current for electric lighting may be obtained either from chemical batteries or from machines termed dynamos. ”

“ If the two wires attached to the plates are now connected with electric lamps, or a motor, or other device, the active material will develop energy in the effort to again change its nature. This energy takes the form of an electric current, which leaves the battery and passes through the conductors and operates the lamps, motors, or other devices in its passage. ”

“ But as instantly, when the current is stopped, this soft iron core ceases to be a magnet, and becomes as it was before--an inert and ordinary piece of iron. What has just been described is always, in some form, one of the indispensable parts of the electromagnetic machines used in industrial electricity, and in all of them except the appliances of electric lighting, and even in that case it is indispensable in producing the current which consumes the points of the carbon, or heats the filament to a white glow. The current may traverse the wire for a hundred miles to reach this little coil. ”

“ If the upper part of the revolving ball be considered as a wire moving from east to west, over the unmarked pole of the earth, the current of electricity in it should be from north to south (99. 114. 150.) ; if the under part be considered as a similar wire, moving from west to east over the same pole, the electric current should be from south to north; and the circulation of electricity should therefore be from north above to south, and below back to north, in a metal ball revolving from east above to west in these latitudes. ”

“ All that I have said about the voltaic arc, the incandescence resulting from resistance to the current's flow, and so forth, in relation to electricity generated by galvanic batteries, applies to electricity generated by induction coils, or by magneto-electric and by dynamo-electric machines. Only it is to be noticed that in some of these machines the currents alternate in direction with each revolution of the swiftly turning coil, in others the currents are always in the same direction, and in yet others the currents may be made to alternate or not, as may be most convenient. ”

“ It has been stated that modern theory recognizes two classes of electricity, the Static and the Dynamic. The difference is, however, solely noticeable in operation. Of the dynamic class there can be no more common and striking example than the now almost universal electric light. Yet, with a sufficient expenditure of chemicals and electrodes, and a sufficient number of cells, electric lighting, either arc or incandescent, can be as effectively accomplished as with the current evolved by a powerful dynamo. ”

“ As these fire-balls travel in a defined line, it is pretty evident from the known laws of electricity, that they must be attracted; and as they are a mile or more in diameter, they must be emitted from a large surface of electric matter; because large nobs give larger sparks, less diffused, and more brightly luminous, than less ones or points, and resist more forceably the emission of the electric matter. What is there in nature can attract them at so great a distance as 1000 miles, and so forceably as to detach an electric spark of a mile diameter? ”

“ The more fertile the soil, and consequently the more vigorous the vegetation, the greater has been the excess of the crop under electric influence. Prof. Lemström’s experiments up to 1887 were carried on in Finland, but he has since repeated his work in France, and demonstrated that the electric influence is the same in any climate, though likely to be injurious under a scorching sun.”
References.—Nollet, “Recherches sur l’Electricité,” pp. 366, 382; Phil. Trans., abridged, Vol. X. p. 384; Electrical Review, London, June 5, 1891, p. ”

“ In an apparatus for lighting gas by electricity, the combination of a wire, through which a current of electricity is passed, actuating mechanism for letting on the gas, an electro-magnet electrically connected with said wire, an armature operated by said electro-magnet, mechanism actuated by said armature, breaking the circuit at the burner tip, and producing there an electric spark or aparks, from the effects of the electro-magnet, for lighting gas, the whole operating automatically. ”

“ Electricity can be generated without burning coal or wood or the use of a furnace. The turbine wheels that are turned by the waters of Niagara Falls, without heat or furnace, can generate a hundred thousand horse power.
The placing of two or three pieces of metal one above another with a moist substance between them will create a voltaic battery. And mines of two or three kinds of metals or ores, when clay or any soft substance between them become moist, will create a battery that will tear up the earth for miles and produce a geyser or an earthquake. ”

“ On these accounts we suppose electrified bodies discharge their atmospheres upon unelectrified bodies more easily and at a greater distance from their angles and points than from their smooth sides.—Those points will also discharge into the air, when the body has too great an electrical atmosphere, without bringing any non-electric near, to receive what is thrown off: For the air, though an electric per se, yet has always more or less water and other non-electric matters mixed with it ”

“ There is no place of the earth or sea where the electric fire may not be collected, by making a communication between it and the rubber of an electric machine. Therefore, considering 121that the whole earth is moist, and that moisture is a conductor of electricity, and that every part of the earth must thus communicate with another, it is certain that the electric matter must diffuse itself as far as the moisture of the earth reaches ”

“ Priestley states that the German electricians generally used several globes at a time and that they could excite such a prodigious power of electricity from “globes, whirled by a large wheel and rubbed with woollen cloth or a dry hand, that, if we may credit their own accounts, the blood could be drawn from the finger by an electric spark ”