30 Electric Light 



contact with the iron, and serious results may happen. Now 

 it is possible so to arrange matters that even if all the cables or 

 wires in the building were adjacent to metallic materials, no 

 serious harm could happen ; and the method is to insert in 

 various parts of the building safety fusible connections, so that 

 if any accidental " short-circuiting" should occur, the safety fuse 

 would instantly melt, and thus stop all further progress of the 

 current. Another ingenious method is by using patent safety 

 cut outs, which consist of a magnet and counter weight or 

 spring. The latter overpowers the magnet's influence under 

 ordinary circumstances, but if the current, from any cause, 

 increases beyond its normal strength, the power of the magnet 

 is increased, and overcomes the weight or spring, and thus stops 

 the current altogether. Again, the cables and wires may all be 

 well protected from any external metallic fittings, and yet there 

 may be danger of the wires getting very hot by reason of them 

 being far too small in sectional area for the current they have 

 to carry. The fusible connections are equally effective in this 

 event. 



As to the advantages of using the electric light for mills, 

 factories, business premises, and private houses, there are 

 numerous* cases where electricity is infinitely superior and very 

 much cheaper than gas ; and on the other hand, there are many 

 places where gas is cheaper, and good enough as an illuminant. 

 Wherever power is available, either by water or steam, then 

 the electric light is by far the best, especially if the hours of 

 lighting are sufficient to permit only a small per-centage of 

 interest on first- cost to fall upon each hour's lighting. Flour 

 mills, which generally work all night, are well adapted for the 

 electric light, whereas large factories, whose ceilings are so low 

 that arc lights are not suitable, and where light is required for 

 only a few hours daily, even in the winter months, do not offer 

 such a good opportunity to make the incandescent electric light 

 pay. Again, in shops, the cost of gas may possibly be somewhat 

 less than the electric light, especially if power has to be specially 

 provided, but the gain annually in the preservation of the fragile 

 goods by the use of the electric light compared to the destruction 



