Edison: Edison system of electric railways. 1891

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Page 5 - top, for "brushes "read "bushes." DYNAMO-ELECTRIC MACHINERY. CHAPTER I. INTRODUCTORY. HISTORICAL NOTES AND ELECTRICAL UNITS. A dynamo-electric machine is a machine for converting energy in the form of mechanical power into energy in the form of electric currents, or vice versA, by the operation of setting conductors (usually in the form of coils of copper wire) to rotate in a magnetic field, or by varying a magnetic field in the presence of conductors.
Page 98 - When fibrous material is used the plastic lamp-black and tar are used to secure it to the platina before carbonizing. By using the carbon wire of such high resistance I am enabled to use fine platinum wires for leading- wires, as they will have a small resistance compared to the burner, and hence will not heat and crack the sealed vacuum-bulb. Platina can only be used, as its expansion is nearly the same as that of glass.
Page 30 - ... Belgian expedition has already started, mainly to carry out deep-sea research around the South Polar area, and that strenuous efforts are being made in Germany to obtain the funds for an expedition on a much larger scale. But our science has to deal not only with the lands of the globe ; its sphere is the whole of the surface of the earth, and all that is thereon, so far at least as distribution is concerned. The department of Oceanography is a comparatively new creation ; indeed, it may be said...
Page 99 - The four claims of the patent are as follows: "(1) An electric lamp for giving light by incandescence, consisting of a filament of carbon of high resistance, made as described, and secured to metallic wires, as set forth. (2) The combination of carbon filaments with a receiver made entirely of glass, and conductors passing through the glass, and from which receiver the air is exhausted, for the purposes set forth.
Page 6 - When a conductor is moved in a field of magnetic force in any way so as to cut the lines of force, there is an electromotive force produced in the conductor, in a direction at right angles to the direction of the motion, and at right angles also to the direction of the lines of force, and to the right of the lines of force, as viewed from the point from which the motion originates.
Page 97 - I have carbonized and used cotton and linen thread, wood splints, papers coiled in various ways, also lamp-black, plumbago, and carbon in various forms, mixed with tar and kneaded so that the same may be rolled out into wires of various lengths and diameters.
Page 97 - ... that carbon filaments may be made by a combination of tar and lamp-black, the latter being previously ignited in a closed crucible for several hours, and...
Page 96 - ... must be of large dimensions and good conductors, and a glass globe cannot be kept tight at the place where the wires pass in and are cemented. Hence the carbon is consumed, because there must be almost a perfect vacuum to render the carbon stable, especially when such carbon is small in mass and high in electrical resistance. The use of a gas in the receiver at the atmospheric pressure, although not attacking the carbon, serves to destroy it in time by 'air washing...
Page 97 - I have discovered that even a cotton thread properly carbonized and placed in a sealed glass bulb exhausted to one millionth of an atmosphere offers from one hundred to five hundred ohms...
Page 12 - have got a thousand times less current or less water, " and we will have a thousandth of an ampere in place of " one ampere, and we will have a thousand volts in place " of one volt, and we will have a fall of water a thousand " feet as against one foot. Now the fall of...

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