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ELECTEIC TEACTION. 

 By Montague Ehys Jones, C.E. 



Whether the present generation has discovered the ultimate 

 force in nature most applicable to the service of man is a 

 question for the scientist of the future to answer. "We can, 

 however, claim this to be the electrical age, as in prehistoric 

 times there were ages of stone and bronze, and in introducing 

 the phenomenon of electricity, as applied to traction, we 

 cannot help being forcibly reminded of the unity and con- 

 tinuity of nature, when we consider how the method of 

 applying this unknown force has, like all other physical and 

 social phenomena, " ever from simpler to more complex 

 grown ;" it now remains an important part of our environ- 

 ment and if we failed to correspond the result would be a 

 retrograde movement of the human species. 



Passing over its agency as a transmitter and reproducer of 

 thought and sound, and other commercial and industrial 

 functions, we come to its latest evolution in its application 

 to the propulsion of railway and tramway cars. Its practical 

 utility was first demonstrated at Berlin, in 1879, by 

 Siemens and Halske, on an experimental line of 500 metres. 

 The train consisted of a small electric locomotive and carriages, 

 which had very small wheels, with two rows of seats running 

 parallel with the rails. The locomotive was fitted up with 

 one of Siemens' dynamo-electric machines, laid horizontally 

 on a frame-work with wheels, the bobbin being parallel to 

 the rails, and the field electric magnets perpendicular thereto. 

 The rotary movement of the bobbin was transformed and 

 transmitted to the driving wheels of the small locomotive 

 by cog wheels, and a bevelled wheel completed the communi- 

 cation of the movement. A bar of iron, to introduce the 

 current, was laid between the two rails, and encased in wood, 

 to insulate it electrically from the soil ; " two spring rubbers 

 attached to the locomotive rested on the bar. The current 

 was transmitted by these rubbers into the machine; 

 after having done its work it passed through the wheels of 

 the locomotive, and back to the generator by the iron rails. 

 It was not necessary for the rails to be completely insulated, 

 for if some of the current escaped into the earth, it still 

 returned to the generator, that being equally connected with 

 the ground." 



The success of this experiment led to other attempts of an 

 exhibitional nature, at Brussels, Durseldorf, Frankfort, and 

 other places with the same result, and then electrical traction 



