204 EXPERIMENTAL GENERAL SCIENCE 



7. In wet weather one may often get a shock by touching a tree with 

 which an electric wire is in contact. Why is a shock not as likely on a 

 dry day? 



8. Is it possible for a lightning flash to move from the earth to a cloud 

 instead of the reverse? 



9. Why is a lightning stroke likely to run along a wire instead of 

 taking a more direct path to the ground? 



10. Why are the supports for electric wires made of glass or porcelain? 



11. Why do electric linemen wear rubber gloves while at work? 



12. If one had to move a naked wire known to be carrying electricity, 

 which would be better to use, a glass or a metal rod? 



13. Why is a cold dry day best for electric experiments? 



14. Why will a Leyden jar fail to be charged if placed on glass? 



15. Hold a piece of glass between the points of discharge on a friction 

 electric machine. How do electricity and magnetism compare as to the 

 ease with which they pass through glass? 



16. Why should a lightning rod be "grounded" by being carried down 

 to permanently moist soil? 



