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be joined outside where the fire might 

 occur. There was no objection to work- 

 ing all the circuits from a pair of omnibus 

 bars in the station, but they should be 

 disconnected in the districts to be lighted. 

 Another objection urged was the drop of 

 external pressure with an increase of 

 current, provided the exciting current 

 was not varied. That was a serious 

 objection when there was one dynamo 

 machine only at work, and when a large 

 part of the total load would, on certain 

 occasions, be taken off suddenly. For 

 example, in ship-lighting it often hap- 

 pened that the lamps were divided be- 

 tween a few circuits, and a large number 

 of lamps must thus be switched off at 

 one instant. This would, with an alter- 

 nator having a large self-induction, pro- 

 duce in the remaining lamps a great 

 jump. But these machines were not 

 intended for ship-lighting or small iso- 

 lated installations ; they were intended 

 for large central stations where there 

 were many thousand lamps, and where 

 the effect of switching on or off even as 



