i8o Lessons on the Human Body. 



FIFTH WALK. 

 A Hill. 



Gravity. How many of you have sleds ? 



What do you do with them ? Draw, ride on, etc. 



When do you ride on them ? 



Did you ever ride on a sled when no one drew it ? How 

 could you do it ? 



How did you get up to the top of the hill ? What made 

 3 r our sled come down ? What is the highest part called ? 

 Top. 



What is the lowest part called ? Bottom. 



What is the part called where you rode ? Slope or side. 



If the top of the hill were very much higher, so high that 

 it went up to the clouds, what would we called it? 

 Mountain. 



If you stood on the top of a hill or a mountain and the 

 mountain should go away and leave you up there, what 

 would you do ? Fall. 



What would make you fall ? There would not be any- 

 thing to hold me up. 



Yes, when there is nothing under us to hold us, we fall to 

 the earth. 



The earth pulls us. Why does the sled slide down the 

 slope ? Because the earth pulls it down. 



Why is it harder to draw a sled uphill than down 

 The earth pulls it back all the time. 



Erosion. When it rains on a hill-top, where does the 

 water go ? Yes, some soaks in and some runs off. When 

 the water soaks in, it makes the soil softer. How does the 

 water look that runs off the sides of the hill ? Yes, it is 

 muddy. What is the running water doing to the hill ? Yes, 

 wearing it away. What will become of the hill some day ? 

 Yes, it will all wear away and become flat. 



Weathering But there is something else in the hill 

 besides the soil and gravel. Henry, what is under the soil 

 in the hill ? How do you know that there is rock under 



