Electrical Railroading; Or, Electricity as Applied to Railroad Transportation

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Drake, 1908 - 924 стор.
 

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Сторінка 336 - MASS AND WEIGHT.— The mass of a body is the quantity of matter in it ; the weight of a body is due to the force of gravity acting upon this matter.
Сторінка 141 - Must be connected with a thoroughly good and permanent ground connection by metallic strips or wires having a conductivity not less than that of a No. 6 B. & S. copper wire, which must be run as nearly in a straight line as possible from the arresters to the earth connection. Ground wires for lightning arresters must not be attached to gas-pipes within the buildings. It is often desirable to introduce a choke coil in circuit between the arresters and the dynamo. In no case should the ground wire...
Сторінка 140 - a. Must be attached to each side of every overhead circuit connected with the station. It is recommended to all electric light and power companies that arresters be connected at intervals over systems in such numbers and so located as to prevent ordinary discharges entering (over the wires) buildings connected to the lines.
Сторінка 90 - Place a hard roll of clothing beneath the body, with the shoulders declining slightly over it. Open the mouth, pull the tongue forward, and with a cloth wipe out Saliva or mucus. Thoroughly loosen the clothing from the neck to the waist, but do not leave the subject's body exposed, for it is essential to keep the body warm; kneel astride the subject's hips, with your hands well opened upon his chest, thumbs pointing toward each other and resting on the lower end of the breastbone ; little fingers...
Сторінка 260 - ... plates. Contraction and expansion of the active material may take place in normal working, and are increased by excessive rates or limits of charging and discharging. This constitutes another cause of disintegration, particularly in plates of the Faure type containing plugs or pellets of lead paste. The fragments which fall from the plates not only involve a loss of material, but are also likely to extend across or gather between the plates, and cause a short circuit. The positive plates are...
Сторінка 321 - ... in- diameter inside the bored out pole pieces, and also a support for the scale. The soft iron cylinder fills up most of the space between the pole pieces, allowing an air space at either side of ]/& in., and in this space a fairly strong, uniform, magnetic field exists.
Сторінка 258 - A. short circuit may cause sulphating, because the cell becomes discharged (on oIx?n circuit), and, when charging, it receives only a low charge compared with the other cells of the series. A battery may become overdischarged or remain discharged a long time, on account of leakage of current due to defective insulation of the cells or circuit; or the plates may become shortcircuited by particles of the active material or foreign substances falling between them.
Сторінка 258 - Sulphating may be removed by carefully scraping the plates. The faulty cells should then be charged at a low rate (about onehalf normal) for a long period. In this way, by fully charging and only partially discharging the cells for a number of times, the unhealthy sulphate is gradually eliminated. When the cells are only slightly sulphated, the latter treatment...
Сторінка 321 - Fig. 148 shows an instrument with the cover removed. A large permanent magnet of U shape is supported by a gun-metal casting screwed to the ends of the limbs, and the whole of the working part is built up on this magnet independent of the case, so that the movement can •be removed bodily from the case by simply taking out one screw which holds the gun-metal casting in place. The inside polar faces of the magnet are surfaced up so as to come closely into contact with wrought-iron pole pieces which...

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