XV. ICE 



Material. When the weather is freezing cold, place some cups and 

 bottles of water outside of a window on the sill. Tip them frequently so 

 as to see the first ice that forms. 



Observation. Look at the freezing cup of water. 

 On what part of the surface does the first ice form ? 

 How many pieces of ice form at one time ? What is 

 the size of the first bits of ice that you see ? What 

 is their shape ? Is the ice the same in all the cups ? 



Just before the cup is frozen over pour off the 

 water. Do you find any particles of ice on the sides 

 of the first bits of ice that formed ? Is the under sur- 

 face of the ice smooth ? What do you find on the 

 under surface ? Is the upper surface of the ice per- 

 fectly level, or does it show tiny ridges ? How are 

 the ridges made? 



Look at the freezing bottle of water. Where 

 does the first ice appear in the bottle? What is 

 the shape of the ice ? How far into the water do 

 the first pieces of ice reach ? 



Drawing. Draw a picture of the first particles of 

 ice that you saw on the freezing cup of water. Draw 

 a picture of the first ice that formed in the bottle of 

 water. 



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