The native authorities had been reluctant to grant that extension, and so they were additionally reluctant to give permission for the promotion of latest lines. If two motors are provided, ought to one give out the car wouldn't be disabled, for the remaining machine would be able to run it to its destination. If two of the generators are related with the bus bars A and B, the current required by the motors might be delivered by the two machines, and if the three generators are placed in service the current might be divided among them. These wires are usually bunched into one or two cables, but they are stored separate from one another by way of strong insulating coverings. Figs. 18, 19.-Outline Elevation and Plan of Electric Railway Car, showing Location of Motors, Controlling Switches, and Connecting Wires. The electric current for working the motors is generated in a energy house that's located at some handy point along the route.

Four wires lead into every motor, and three or 4 into each of the packing containers marked G G. If the motors had been required to run in a single direction only, then two wires would be ample to convey the present to them; but as they must run in either path, at the least three wires are crucial, but in virtually every case four are used, as the outcomes obtained thereby are extra satisfactory. After two or three ineffectual efforts have been made to begin all the automobiles together the motormen will conclude to go easy, and set a few in movement at a time. This controlling mechanism should even be so organized that the direction of movement may be different with the greatest certainty and as rapidly as could at any time be required. In order that this end result may be efficiently accomplished, each motor is fabricated from adequate capacity to run the automobile with out being overtaxed, except the load is abnormally large; however even underneath the latter conditions the machine will in ninety-nine instances out of a hundred withstand the strain.

This wire d d, as will probably be seen, runs in each instructions, and ends in the stands C C. These latter are the controlling switches, and are supplied with a handle h, by way of which the present is turned on or off from the motors, and is directed by means of them in such a means as to make the car run in whichever course may be desired. If the automobiles are provided with a single motor, when one becomes disabled from any cause it has to attend until overtaken by the automotive behind it, so that it may be pushed by the latter to the top of the road. Unless the highway may be very small and operates but just a few ears, this wire won't be sufficient to carry all the present, therefore generally there are a variety of supplementary wires, which are referred to as feeders. In appearance, independence of thought, and in some ways there was great resemblance between uncle and nephew, so that I used to hope that a nook of the mantle of William Thomson may relaxation on David King. Thomson wanted a receiving instrument which, not like the ordinary telegraph instruments used in post-workplaces and railway stations, may render the interpretation of such suggestions possible within the hands of an expert signaler, and he devised the mirror galvanometer speaking instrument to acquire this result.

But these shocks only sent sparks by means of the gutta-percha insulating coating and hurried the poor cable to its doom, in order that even the three words per minute which might have been the utmost restrict of speed doable had this cable been fully uninjured, had been changed by absolute silence. As well as, speed-controlling units must be supplied whereby the velocity could also be modified at will and within the shortest attainable time, and with as nearly absolute precision as doable. These two switches are called emergency switches; they are offered simply as a security machine, and are used only when the primary switches get out of order and the motorman cannot flip the current off in the regular approach. Fig. 20 exhibits a car truck geared up with two motors and magnetic brakes, one on each axle. The containers G G are called rheostats, and are merely gadgets through which the present is run in order to reduce the pace of the automobile, what is electric cable and in addition for the purpose of graduating the strength of the current that passes by the motors in the act of starting.