COMPUTING THE COST OP LIGHTING 375 



26. How much window space has your school room as com- 

 pared with the floor space? 



27. Determine the proper amount of window space for your living 

 room, dining room, etc., at home. 



28. What kind of light is best for studying? 



29. Why is direct sunlight injurious for studying? 



30. How much above your eyes is the window when you are 

 studying? 



31. Because of danger from fire some have opposed the build- 

 ing of the bottoms of windows higher than the pupils' eyes. Why 

 is this objection a poor one? 



32. Why should primary grade children always have rooms 

 on the bottom floor? 



33. Have you any " breeze windows" in your school room? 

 If so, are they properly protected? 



'34. At what time of the day does direct light enter the room 

 where you study? 



35. At what part of the day do you have ndirect light in your 

 school room? 



36. At what parts of the day do you have direct and indirect 

 light from the sun in your living rooms at home? 



37. Why do some rooms appear darker than others with the 

 same amount of light entering? 



38. Why should rooms be well lighted with sunlight? 



39. Why is it possible to light rooms by sunlight even though 

 the sunlight does not come 'directly into them? 



40. What causes the wavy appearance over a hot stove or 

 over a sandy beach during a hot day? 



41. What part of this section is of greatest importance? 



COMPUTING THE COST OF LIGHTING 



Measurement of Lights. Lights are measured by candle power. 

 As the words suggest, a light of a certain candle power means the 

 number of times more light that particular light gives than a candle. 

 Standard candles are used for this purpose. To say a lamp has a 

 candle power marked sixteen (16) means that that light will give 



