. The street railway review . he railway escaping, bj means of damp earth,minerals, pipes and other conducting substances leadinginto the lower earth. The resistance of the circuit and,consequent]) the strength of current available at the car,varies as these leaks increase or decrease. The extent towhich this current will scatter is probably best shown byits effect on telephone wires, which it will follow for amile or more to reach the earth at the distant end. There 153 are, plainlj-, but two ways of avoiding these troubles;one,by completing the metallic circuit overhead, requiring adouble tr
. The street railway review . he railway escaping, bj means of damp earth,minerals, pipes and other conducting substances leadinginto the lower earth. The resistance of the circuit and,consequent]) the strength of current available at the car,varies as these leaks increase or decrease. The extent towhich this current will scatter is probably best shown byits effect on telephone wires, which it will follow for amile or more to reach the earth at the distant end. There 153 are, plainlj-, but two ways of avoiding these troubles;one,by completing the metallic circuit overhead, requiring adouble trolley, and the other, with a single trolle\ line, tosecure perfect contact with the earth immediately underthe car, that is by a path offering no resistance, so that allthe electricity set free at that point will be absorbed bythe earth. The resistance of the entire circuit will thendepend only on the overhead portion, insuring the maxi-mum energy at the car. The track rails should never beconnected direct with the The accompanying cut shows the manner of connectingin the Sabold system. HOSTON. Some experiments in this field have been tried byChas. H. Morse, the superintendent of the fire alarm andpolice telegraph systems of Cambridge, Mass. had found that in various parts of Cambridge thepower currents of the West End Railway Company,escaping from the return wires to the water and gaspipes, have prematurely corroded these pipes. In a recent interview upon the subject Mr. Morse hassaid: When I took charge of the Cambridge fire alarmand police telegraph system, some time ago, I found thatmen under me were having a good deal of trouble in dis-covering grounds, that is, contact of the fire alarm wireswith other wires. Upon investigation I soon learned thatthe railway currents did not have a low enough resist-ance path upon which to return to the power in April, 1S92, I notified the West End com-pany that its return wires were not sufficient
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Keywords: ., book, bookcentury1800, bookdecade1890, booksubjectstreetrailroads
