156 NATURE STUDY 



frost, because then half the work is clone for him. But 

 it does more than this. It helps to form the soil by 

 breaking up the rocks. 



Methods : 



Let the kettle boil again. 



Where else have you seen white masses like this ? 

 What are they called ? From what are the clouds of 

 steam formed ? How ? From what are clouds formed ? 

 How? 



When the cold plate was brought in contact with the 

 steam, what happened ? Why ? What happened to the 

 drops of water ? Why ? What causes drops of water to 

 form from clouds ? Why do these grow larger ? Why 

 do they fall as rain ? 



If the immediate effects of rain on the soil of the 

 school yard were observed in the fall, now will be a most 

 excellent time to review and make coherent the know- 

 ledge thus obtained by the children. 



If, however, these observations were not made, it will 

 be better to wait until the time of spring showers. For 

 the sake of convenience, however, the method of teach- 

 ing the effects of rain will be given here. 



What kind of a mark did the raindrops make in the 

 soil of the school yard ? ^\T.iy ? What became of these 

 drops ? What good did the rain that sank into the soil 

 do for the plants ? Why ? How ? What happened to 

 the drops that staid above ground ? "VMien they found a 

 channel, what did they do to it ? AVhy is the gutter 

 stream so large ? Why is it so dirty ? What will hap- 

 pen to this dirt after a while ? How do you know ? 

 How are rivers formed? What ^vork do they do as 



