m NATURE-STUDY LESSONS. 



7. When does the dew on the grass disappear ? Why 

 then? 



8. Since the water in the saucer disappeared into the 

 atmosphere what becomes of part of the water of our 

 rivers, lakes, swamps, and seas? 



9. Place a wet saucer outside in the winter time. 

 After some time, observe whether it is dry or not. 



10. (a) Observe patches of snow in the fields during 



cold yet stormless winter weather. 

 {6) How do the patches now compare in size with 



the same when first observed ? 

 (c) What caused the difference ? 



11. Try to discover whether ice always melts before 

 evaporation. 



12. Where does all the vapor from these sources go? 



13. (a) Place over a flame a test-tube half filled with 



water and fitted with a cork, through which 

 is inserted a piece of glass-tubing, its lower 

 end being above the surface of the water. 



{6) What takes place almost immediately after the 

 application of the heat ? 



(c) What caused these to rise ? 



{d) Describe the condition of the water while boil- 

 ing is taking place. 



(e) How do the bubbles now seen compare in size 

 and action with the bubbles first observed ? 



(/) Observe the bubbles bursting and determine 

 what they contain. 



(£■) What do you observe issuing from the glass- 

 tubing .' 



(A) Observe carefully where it is first visible. 



