Electricity 239 



instruments. It requires the high voltage of a city 

 power line to make a dangerous electric arc. 



So many fires are caused by electric arcs forming in 

 buildings, that you had better go back to the beginning 

 of this section and read it all through again carefully. 

 It may save your home and even your life. 



After you have reread this section, test your under- 

 standing of it by answering the following questions : 



1. How can you make an electric arc? 



2. Why should wires not be twisted together to make 

 electric connections? 



3. Why should wires be brought into houses and 

 through walls in iron conduits? 



4. Why should you pull out the plug of an electric 

 iron, percolator, toaster, heater, or stove? 



5 . Why do fire commissions condemn extension lights ? 



6. If you use an extension light, where should it be 

 turned off? 



7. If you hear a sizzling and sputtering in your 

 electric-light socket, what does it mean? What should 

 you do? 



8. Is there any danger in defective sockets with 

 switches that do not snap off completely? What is 

 the danger ? 



9. In Application 55, page 228, if the rat had gnawed 

 the wire in two while the electric iron was being used, 

 would anything have happened to the rat? Would 

 there have been any danger to the house? 



10. Where a wire is screwed into an electric-light 

 socket, what harm, if any, might result from not screw- 

 ing it in tightly? 



