144 GENERAL SCIENCE 



the New England States, is very changeable. The wind 

 coming from the south is warm in winter, while the 

 northwestern winds are extremely cold. In summer a 

 southern wind is cool and a northwestern wind is 

 usually warm. Ask your teacher to explain this. The 

 climate of islands is kept nearly constant by the water 

 around them. 



QUESTIONS AND EXERCISES 



1. Of what two elements is water composed ? 



2. Why does it rain more on the western slope of the Rocky 

 Mountains than on the eastern slope ? 



3. Is your water at home free from germs and harmful com- 

 pounds ? 



4. What are the ways of purifying water ? Which method do 

 you use at home ? 



5. So far as water is concerned, what are the dangers while 

 camping ? How avoid them ? 



6. Are there any caves and valleys where you live? What 

 made them ? 



7. On the basis of your own experience, is a cubic foot of ice 

 heavier than a cubic foot of water ? 



8. Where does the water of the Gulf Stream get its heat to warm 

 Europe ? How does it carry this heat ? 



9. Why does San Francisco have a warmer climate than New 

 York? 



